const char cgiedit_rcs[] = "$Id: cgiedit.c,v 1.88 2016/02/26 12:29:38 fabiankeil Exp $";
/*********************************************************************
 *
 * File        :  $Source: /cvsroot/ijbswa/current/cgiedit.c,v $
 *
 * Purpose     :  CGI-based actionsfile editor.
 *
 *                NOTE: The CGIs in this file use parameter names
 *                such as "f" and "s" which are really *BAD* choices.
 *                However, I'm trying to save bytes in the
 *                edit-actions-list HTML page - the standard actions
 *                file generated a 550kbyte page, which is ridiculous.
 *
 *                Stick to the short names in this file for consistency.
 *
 * Copyright   :  Written by and Copyright (C) 2001-2014 the
 *                Privoxy team. http://www.privoxy.org/
 *
 *                Based on the Internet Junkbuster originally written
 *                by and Copyright (C) 1997 Anonymous Coders and
 *                Junkbusters Corporation.  http://www.junkbusters.com
 *
 *                This program is free software; you can redistribute it
 *                and/or modify it under the terms of the GNU General
 *                Public License as published by the Free Software
 *                Foundation; either version 2 of the License, or (at
 *                your option) any later version.
 *
 *                This program is distributed in the hope that it will
 *                be useful, but WITHOUT ANY WARRANTY; without even the
 *                implied warranty of MERCHANTABILITY or FITNESS FOR A
 *                PARTICULAR PURPOSE.  See the GNU General Public
 *                License for more details.
 *
 *                The GNU General Public License should be included with
 *                this file.  If not, you can view it at
 *                http://www.gnu.org/copyleft/gpl.html
 *                or write to the Free Software Foundation, Inc., 59
 *                Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 **********************************************************************/


#include "config.h"

/*
 * FIXME: Following includes copied from cgi.c - which are actually needed?
 */

#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <ctype.h>
#include <string.h>
#include <assert.h>
#include <sys/stat.h>

#include "project.h"
#include "cgi.h"
#include "cgiedit.h"
#include "cgisimple.h"
#include "list.h"
#include "encode.h"
#include "actions.h"
#include "miscutil.h"
#include "errlog.h"
#include "loaders.h"
#ifdef FEATURE_TOGGLE
/* loadcfg.h is for global_toggle_state only */
#include "loadcfg.h"
#endif /* def FEATURE_TOGGLE */
#include "urlmatch.h"

const char cgiedit_h_rcs[] = CGIEDIT_H_VERSION;


#ifdef FEATURE_CGI_EDIT_ACTIONS

/**
 * A line in an editable_file.
 */
struct file_line
{
   /** Next entry in the linked list */
   struct file_line * next;

   /** The raw data, to write out if this line is unmodified. */
   char * raw;

   /** Comments and/or whitespace to put before this line if it's modified
       and then written out. */
   char * prefix;

   /** The actual data, as a string.  Line continuation and comment removal
       are performed on the data read from file before it's stored here, so
       it will be a single line of data.  */
   char * unprocessed;

   /** The type of data on this line.  One of the FILE_LINE_xxx constants. */
   int type;

   /** The actual data, processed into some sensible data type. */
   union
   {

      /** An action specification. */
      struct action_spec action[1];

      /** A name=value pair. */
      struct
      {

         /** The name in the name=value pair. */
         char * name;

         /** The value in the name=value pair, as a string. */
         char * svalue;

         /** The value in the name=value pair, as an integer. */
         int ivalue;

      } setting;

   } data;

};

/** This file_line has not been processed yet. */
#define FILE_LINE_UNPROCESSED           1

/** This file_line is blank. Can only appear at the end of a file, due to
    the way the parser works. */
#define FILE_LINE_BLANK                 2

/** This file_line says {{alias}}. */
#define FILE_LINE_ALIAS_HEADER          3

/** This file_line defines an alias. */
#define FILE_LINE_ALIAS_ENTRY           4

/** This file_line defines an {action}. */
#define FILE_LINE_ACTION                5

/** This file_line specifies a URL pattern. */
#define FILE_LINE_URL                   6

/** This file_line says {{settings}}. */
#define FILE_LINE_SETTINGS_HEADER       7

/** This file_line is in a {{settings}} block. */
#define FILE_LINE_SETTINGS_ENTRY        8

/** This file_line says {{description}}. */
#define FILE_LINE_DESCRIPTION_HEADER    9

/** This file_line is in a {{description}} block. */
#define FILE_LINE_DESCRIPTION_ENTRY    10

/*
 * Number of file modification time mismatches
 * before the CGI editor gets turned off.
 */
#define ACCEPTABLE_TIMESTAMP_MISMATCHES 3

/**
 * A configuration file, in a format that can be edited and written back to
 * disk.
 */
struct editable_file
{
   struct file_line * lines;  /**< The contents of the file.  A linked list of lines. */
   const char * filename;     /**< Full pathname - e.g. "/etc/privoxy/wibble.action". */
   unsigned identifier;       /**< The file name's position in csp->config->actions_file[]. */
   const char * version_str;  /**< Last modification time, as a string.  For CGI param. */
                              /**< Can be used in URL without using url_param(). */
   unsigned version;          /**< Last modification time - prevents chaos with
                                   the browser's "back" button.  Note that this is a
                                   time_t cast to an unsigned.  When comparing, always
                                   cast the time_t to an unsigned, and *NOT* vice-versa.
                                   This may lose the top few bits, but they're not
                                   significant anyway. */
   int newline;               /**< Newline convention - one of the NEWLINE_xxx constants.
                                   Note that changing this after the file has been
                                   read in will cause a mess. */
   struct file_line * parse_error; /**< On parse error, this is the offending line. */
   const char * parse_error_text;  /**< On parse error, this is the problem.
                                        (Statically allocated) */
};

/**
 * Information about the filter types.
 * Used for macro replacement in cgi_edit_actions_for_url.
 */
struct filter_type_info
{
   const int multi_action_index; /**< The multi action index as defined in project.h */
   const char *macro_name;       /**< Name of the macro that has to be replaced
                                      with the prepared templates.
                                      For example "content-filter-params" */
   const char *type;             /**< Name of the filter type,
                                      for example "server-header-filter". */
   /* XXX: check if these two can be combined. */
   const char *disable_all_option; /**< Name of the catch-all radio option that has
                                        to be checked or unchecked for this filter type. */
   const char *disable_all_param;  /**< Name of the parameter that causes all filters of
                                        this type to be disabled. */
   const char *abbr_type;        /**< Abbreviation of the filter type, usually the
                                      first or second character capitalized */
   const char *anchor;           /**< Anchor for the User Manual link,
                                      for example "SERVER-HEADER-FILTER"  */
};

/* Accessed by index, keep the order in the way the FT_ macros are defined. */
static const struct filter_type_info filter_type_info[] =
{
   {
      ACTION_MULTI_FILTER,
      "content-filter-params", "filter",
      "filter-all", "filter_all",
      "F", "FILTER"
   },
   {
      ACTION_MULTI_CLIENT_HEADER_FILTER,
      "client-header-filter-params", "client-header-filter",
      "client-header-filter-all", "client_header_filter_all",
      "C", "CLIENT-HEADER-FILTER"
   },
   {
      ACTION_MULTI_SERVER_HEADER_FILTER,
      "server-header-filter-params", "server-header-filter",
      "server-header-filter-all", "server_header_filter_all",
      "S", "SERVER-HEADER-FILTER"
   },
   {
      ACTION_MULTI_CLIENT_HEADER_TAGGER,
      "client-header-tagger-params", "client-header-tagger",
      "client-header-tagger-all", "client_header_tagger_all",
      "L", "CLIENT-HEADER-TAGGER"
   },
   {
      ACTION_MULTI_SERVER_HEADER_TAGGER,
      "server-header-tagger-params", "server-header-tagger",
      "server-header-tagger-all", "server_header_tagger_all",
      "E", "SERVER-HEADER-TAGGER"
   },
#ifdef FEATURE_EXTERNAL_FILTERS
   {
      ACTION_MULTI_EXTERNAL_FILTER,
      "external-content-filter-params", "external-filter",
      "external-content-filter-all", "external_content_filter_all",
      "E", "EXTERNAL-CONTENT-FILTER"
   },
#endif
};

/* FIXME: Following non-static functions should be prototyped in .h or made static */

/* Functions to read and write arbitrary config files */
jb_err edit_read_file(struct client_state *csp,
                      const struct map *parameters,
                      int require_version,
                      struct editable_file **pfile);
jb_err edit_write_file(struct editable_file * file);
void   edit_free_file(struct editable_file * file);

/* Functions to read and write actions files */
jb_err edit_parse_actions_file(struct editable_file * file);
jb_err edit_read_actions_file(struct client_state *csp,
                              struct http_response *rsp,
                              const struct map *parameters,
                              int require_version,
                              struct editable_file **pfile);

/* Error handlers */
jb_err cgi_error_modified(struct client_state *csp,
                          struct http_response *rsp,
                          const char *filename);
jb_err cgi_error_parse(struct client_state *csp,
                       struct http_response *rsp,
                       struct editable_file *file);
jb_err cgi_error_file(struct client_state *csp,
                      struct http_response *rsp,
                      const char *filename);
jb_err cgi_error_file_read_only(struct client_state *csp,
                                struct http_response *rsp,
                                const char *filename);

/* Internal arbitrary config file support functions */
static jb_err edit_read_file_lines(FILE *fp, struct file_line ** pfile, int *newline);
static void edit_free_file_lines(struct file_line * first_line);

/* Internal actions file support functions */
static int match_actions_file_header_line(const char * line, const char * name);
static jb_err split_line_on_equals(const char * line, char ** pname, char ** pvalue);

/* Internal parameter parsing functions */
static jb_err get_url_spec_param(struct client_state *csp,
                                 const struct map *parameters,
                                 const char *name,
                                 char **pvalue);


/* Internal actionsfile <==> HTML conversion functions */
static jb_err map_radio(struct map * exports,
                        const char * optionname,
                        const char * values,
                        int value);
static jb_err actions_to_radio(struct map * exports,
                               const struct action_spec *action);
static jb_err actions_from_radio(const struct map * parameters,
                                 struct action_spec *action);


static jb_err map_copy_parameter_html(struct map *out,
                                      const struct map *in,
                                      const char *name);

static jb_err get_file_name_param(struct client_state *csp,
	                                   const struct map *parameters,
	                                   const char *param_name,
	                                   const char **pfilename);

/* Internal convenience functions */
static char *section_target(const unsigned sectionid);

/*********************************************************************
 *
 * Function    :  section_target
 *
 * Description :  Given an unsigned (section id) n, produce a dynamically
 *                allocated string of the form #l<n>, for use in link
 *                targets.
 *
 *                XXX: The hash should be moved into the templates
 *                to make this function more generic and render
 *                stringify() obsolete.
 *
 * Parameters  :
 *          1  :  sectionid = start line number of section
 *
 * Returns     :  String with link target, or NULL if out of
 *                memory
 *
 *********************************************************************/
static char *section_target(const unsigned sectionid)
{
   char buf[30];

   snprintf(buf, sizeof(buf), "#l%u", sectionid);
   return(strdup(buf));

}


/*********************************************************************
 *
 * Function    :  stringify
 *
 * Description :  Convert a number into a dynamically allocated string.
 *
 * Parameters  :
 *          1  :  number = The number to convert.
 *
 * Returns     :  String with link target, or NULL if out of memory
 *
 *********************************************************************/
static char *stringify(const unsigned number)
{
   char buf[6];

   snprintf(buf, sizeof(buf), "%u", number);
   return strdup(buf);
}


/*********************************************************************
 *
 * Function    :  map_copy_parameter_html
 *
 * Description :  Copy a CGI parameter from one map to another, HTML
 *                encoding it.
 *
 * Parameters  :
 *          1  :  out = target map
 *          2  :  in = source map
 *          3  :  name = name of cgi parameter to copy
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the parameter doesn't exist
 *                                  in the source map
 *
 *********************************************************************/
static jb_err map_copy_parameter_html(struct map *out,
                                      const struct map *in,
                                      const char *name)
{
   const char * value;
   jb_err err;

   assert(out);
   assert(in);
   assert(name);

   value = lookup(in, name);
   err = map(out, name, 1, html_encode(value), 0);

   if (err)
   {
      /* Out of memory */
      return err;
   }
   else if (*value == '\0')
   {
      return JB_ERR_CGI_PARAMS;
   }
   else
   {
      return JB_ERR_OK;
   }
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_url_form
 *
 * Description :  CGI function that displays a form for
 *                edit-actions-url
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters
 *           i : (action index) Identifies the file to edit
 *           v : (version) File's last-modified time
 *           p : (pattern) Line number of pattern to edit
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_url_form(struct client_state *csp,
                                 struct http_response *rsp,
                                 const struct map *parameters)
{
   struct map * exports;
   unsigned patternid;
   struct editable_file * file;
   struct file_line * cur_line;
   unsigned line_number;
   unsigned section_start_line_number = 0;
   jb_err err;

   assert(csp);
   assert(rsp);
   assert(parameters);

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "p", &patternid);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   cur_line = file->lines;

   for (line_number = 1; (cur_line != NULL) && (line_number < patternid); line_number++)
   {
      if (cur_line->type == FILE_LINE_ACTION)
      {
         section_start_line_number = line_number;
      }
      cur_line = cur_line->next;
   }

   if ( (cur_line == NULL)
     || (line_number != patternid)
     || (patternid < 1U)
     || (cur_line->type != FILE_LINE_URL))
   {
      /* Invalid "patternid" parameter */
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      edit_free_file(file);
      return JB_ERR_MEMORY;
   }

   err = map(exports, "f", 1, stringify(file->identifier), 0);
   if (!err) err = map(exports, "v", 1, file->version_str, 1);
   if (!err) err = map(exports, "p", 1, url_encode(lookup(parameters, "p")), 0);
   if (!err) err = map(exports, "u", 1, html_encode(cur_line->unprocessed), 0);
   if (!err) err = map(exports, "jumptarget", 1, section_target(section_start_line_number), 0);

   edit_free_file(file);

   if (err)
   {
      free_map(exports);
      return err;
   }

   return template_fill_for_cgi(csp, "edit-actions-url-form", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_add_url_form
 *
 * Description :  CGI function that displays a form for
 *                edit-actions-url
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *           f : (filename) Identifies the file to edit
 *           v : (version) File's last-modified time
 *           s : (section) Line number of section to edit
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_add_url_form(struct client_state *csp,
                                     struct http_response *rsp,
                                     const struct map *parameters)
{
   struct map *exports;
   jb_err err;

   assert(csp);
   assert(rsp);
   assert(parameters);

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      return JB_ERR_MEMORY;
   }

   err = map_copy_parameter_html(exports, parameters, "f");
   if (!err) err = map_copy_parameter_html(exports, parameters, "v");
   if (!err) err = map_copy_parameter_html(exports, parameters, "s");

   if (err)
   {
      free_map(exports);
      return err;
   }

   return template_fill_for_cgi(csp, "edit-actions-add-url-form", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_remove_url_form
 *
 * Description :  CGI function that displays a form for
 *                edit-actions-url
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *           f : (number)  The action file identifier.
 *           v : (version) File's last-modified time
 *           p : (pattern) Line number of pattern to edit
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_remove_url_form(struct client_state *csp,
                                     struct http_response *rsp,
                                     const struct map *parameters)
{
   struct map * exports;
   unsigned patternid;
   struct editable_file * file;
   struct file_line * cur_line;
   unsigned line_number;
   unsigned section_start_line_number = 0;
   jb_err err;

   assert(csp);
   assert(rsp);
   assert(parameters);

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "p", &patternid);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   cur_line = file->lines;

   for (line_number = 1; (cur_line != NULL) && (line_number < patternid); line_number++)
   {
      if (cur_line->type == FILE_LINE_ACTION)
      {
         section_start_line_number = line_number;
      }
      cur_line = cur_line->next;
   }

   if ( (cur_line == NULL)
     || (line_number != patternid)
     || (patternid < 1U)
     || (cur_line->type != FILE_LINE_URL))
   {
      /* Invalid "patternid" parameter */
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      edit_free_file(file);
      return JB_ERR_MEMORY;
   }

   err = map(exports, "f", 1, stringify(file->identifier), 0);
   if (!err) err = map(exports, "v", 1, file->version_str, 1);
   if (!err) err = map(exports, "p", 1, url_encode(lookup(parameters, "p")), 0);
   if (!err) err = map(exports, "u", 1, html_encode(cur_line->unprocessed), 0);
   if (!err) err = map(exports, "jumptarget", 1, section_target(section_start_line_number), 0);
   if (!err) err = map(exports, "actions-file", 1, html_encode(file->filename), 0);

   edit_free_file(file);

   if (err)
   {
      free_map(exports);
      return err;
   }

   return template_fill_for_cgi(csp, "edit-actions-remove-url-form", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  edit_write_file
 *
 * Description :  Write a complete file to disk.
 *
 * Parameters  :
 *          1  :  file = File to write.
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_FILE   on error writing to file.
 *                JB_ERR_MEMORY on out of memory
 *
 *********************************************************************/
jb_err edit_write_file(struct editable_file * file)
{
   FILE * fp;
   struct file_line * cur_line;
   struct stat statbuf[1];
   char version_buf[22]; /* 22 = ceil(log10(2^64)) + 2 = max number of
                            digits in time_t, assuming this is a 64-bit
                            machine, plus null terminator, plus one
                            for paranoia */

   assert(file);
   assert(file->filename);

   if (NULL == (fp = fopen(file->filename, "wb")))
   {
      return JB_ERR_FILE;
   }

   cur_line = file->lines;
   while (cur_line != NULL)
   {
      if (cur_line->raw)
      {
         if (fputs(cur_line->raw, fp) < 0)
         {
            fclose(fp);
            return JB_ERR_FILE;
         }
      }
      else
      {
         if (cur_line->prefix)
         {
            if (fputs(cur_line->prefix, fp) < 0)
            {
               fclose(fp);
               return JB_ERR_FILE;
            }
         }
         if (cur_line->unprocessed)
         {

            if (NULL != strchr(cur_line->unprocessed, '#'))
            {
               /* Must quote '#' characters */
               int numhash = 0;
               size_t len;
               char * src;
               char * dest;
               char * str;

               /* Count number of # characters, so we know length of output string */
               src = cur_line->unprocessed;
               while (NULL != (src = strchr(src, '#')))
               {
                  numhash++;
                  src++;
               }
               assert(numhash > 0);

               /* Allocate new memory for string */
               len = strlen(cur_line->unprocessed) + (size_t)numhash;
               str = malloc_or_die(len + 1);

               /* Copy string but quote hashes */
               src  = cur_line->unprocessed;
               dest = str;
               while (*src)
               {
                  if (*src == '#')
                  {
                     *dest++ = '\\';
                     numhash--;
                     assert(numhash >= 0);
                  }
                  *dest++ = *src++;
               }
               *dest = '\0';

               assert(numhash == 0);
               assert(strlen(str) == len);
               assert(str == dest - len);
               assert(src - len <= cur_line->unprocessed);

               if ((strlen(str) != len) || (numhash != 0))
               {
                  /*
                   * Escaping didn't work as expected, go spread the news.
                   * Only reached in non-debugging builds.
                   */
                  log_error(LOG_LEVEL_ERROR,
                     "Looks like hash escaping failed. %s might be corrupted now.",
                     file->filename);
               }

               if (fputs(str, fp) < 0)
               {
                  free(str);
                  fclose(fp);
                  return JB_ERR_FILE;
               }

               free(str);
            }
            else
            {
               /* Can write without quoting '#' characters. */
               if (fputs(cur_line->unprocessed, fp) < 0)
               {
                  fclose(fp);
                  return JB_ERR_FILE;
               }
            }
            if (fputs(NEWLINE(file->newline), fp) < 0)
            {
               fclose(fp);
               return JB_ERR_FILE;
            }
         }
         else
         {
            /* FIXME: Write data from file->data->whatever */
            assert(0);
         }
      }
      cur_line = cur_line->next;
   }

   fclose(fp);


   /* Update the version stamp in the file structure, since we just
    * wrote to the file & changed it's date.
    */
   if (stat(file->filename, statbuf) < 0)
   {
      /* Error, probably file not found. */
      return JB_ERR_FILE;
   }
   file->version = (unsigned)statbuf->st_mtime;

   /* Correct file->version_str */
   freez(file->version_str);
   snprintf(version_buf, sizeof(version_buf), "%u", file->version);
   version_buf[sizeof(version_buf)-1] = '\0';
   file->version_str = strdup_or_die(version_buf);

   return JB_ERR_OK;
}


/*********************************************************************
 *
 * Function    :  edit_free_file
 *
 * Description :  Free a complete file in memory.
 *
 * Parameters  :
 *          1  :  file = Data structure to free.
 *
 * Returns     :  N/A
 *
 *********************************************************************/
void edit_free_file(struct editable_file * file)
{
   if (!file)
   {
      /* Silently ignore NULL pointer */
      return;
   }

   edit_free_file_lines(file->lines);
   freez(file->version_str);
   file->version = 0;
   file->parse_error_text = NULL; /* Statically allocated */
   file->parse_error = NULL;

   free(file);
}


/*********************************************************************
 *
 * Function    :  edit_free_file_lines
 *
 * Description :  Free an entire linked list of file lines.
 *
 * Parameters  :
 *          1  :  first_line = Data structure to free.
 *
 * Returns     :  N/A
 *
 *********************************************************************/
static void edit_free_file_lines(struct file_line * first_line)
{
   struct file_line * next_line;

   while (first_line != NULL)
   {
      next_line = first_line->next;
      first_line->next = NULL;
      freez(first_line->raw);
      freez(first_line->prefix);
      freez(first_line->unprocessed);
      switch(first_line->type)
      {
         case 0: /* special case if memory zeroed */
         case FILE_LINE_UNPROCESSED:
         case FILE_LINE_BLANK:
         case FILE_LINE_ALIAS_HEADER:
         case FILE_LINE_SETTINGS_HEADER:
         case FILE_LINE_DESCRIPTION_HEADER:
         case FILE_LINE_DESCRIPTION_ENTRY:
         case FILE_LINE_ALIAS_ENTRY:
         case FILE_LINE_URL:
            /* No data is stored for these */
            break;

         case FILE_LINE_ACTION:
            free_action(first_line->data.action);
            break;

         case FILE_LINE_SETTINGS_ENTRY:
            freez(first_line->data.setting.name);
            freez(first_line->data.setting.svalue);
            break;
         default:
            /* Should never happen */
            assert(0);
            break;
      }
      first_line->type = 0; /* paranoia */
      free(first_line);
      first_line = next_line;
   }
}


/*********************************************************************
 *
 * Function    :  match_actions_file_header_line
 *
 * Description :  Match an actions file {{header}} line
 *
 * Parameters  :
 *          1  :  line = String from file
 *          2  :  name = Header to match against
 *
 * Returns     :  0 iff they match.
 *
 *********************************************************************/
static int match_actions_file_header_line(const char * line, const char * name)
{
   size_t len;

   assert(line);
   assert(name);

   /* Look for "{{" */
   if ((line[0] != '{') || (line[1] != '{'))
   {
      return 1;
   }
   line += 2;

   /* Look for optional whitespace */
   while ((*line == ' ') || (*line == '\t'))
   {
      line++;
   }

   /* Look for the specified name (case-insensitive) */
   len = strlen(name);
   if (0 != strncmpic(line, name, len))
   {
      return 1;
   }
   line += len;

   /* Look for optional whitespace */
   while ((*line == ' ') || (*line == '\t'))
   {
      line++;
   }

   /* Look for "}}" and end of string*/
   if ((line[0] != '}') || (line[1] != '}') || (line[2] != '\0'))
   {
      return 1;
   }

   /* It matched!! */
   return 0;
}


/*********************************************************************
 *
 * Function    :  match_actions_file_header_line
 *
 * Description :  Match an actions file {{header}} line
 *
 * Parameters  :
 *          1  :  line = String from file.  Must not start with
 *                       whitespace (else infinite loop!)
 *          2  :  pname = Destination for name
 *          2  :  pvalue = Destination for value
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_PARSE  if there's no "=" sign, or if there's
 *                              nothing before the "=" sign (but empty
 *                              values *after* the "=" sign are legal).
 *
 *********************************************************************/
static jb_err split_line_on_equals(const char * line, char ** pname, char ** pvalue)
{
   const char * name_end;
   const char * value_start;
   size_t name_len;

   assert(line);
   assert(pname);
   assert(pvalue);
   assert(*line != ' ');
   assert(*line != '\t');

   *pname = NULL;
   *pvalue = NULL;

   value_start = strchr(line, '=');
   if ((value_start == NULL) || (value_start == line))
   {
      return JB_ERR_PARSE;
   }

   name_end = value_start - 1;

   /* Eat any whitespace before the '=' */
   while ((*name_end == ' ') || (*name_end == '\t'))
   {
      /*
       * we already know we must have at least 1 non-ws char
       * at start of buf - no need to check
       */
      name_end--;
   }

   name_len = (size_t)(name_end - line) + 1; /* Length excluding \0 */
   *pname = malloc_or_die(name_len + 1);
   strncpy(*pname, line, name_len);
   (*pname)[name_len] = '\0';

   /* Eat any the whitespace after the '=' */
   value_start++;
   while ((*value_start == ' ') || (*value_start == '\t'))
   {
      value_start++;
   }

   if (NULL == (*pvalue = strdup(value_start)))
   {
      free(*pname);
      *pname = NULL;
      return JB_ERR_MEMORY;
   }

   return JB_ERR_OK;
}


/*********************************************************************
 *
 * Function    :  edit_parse_actions_file
 *
 * Description :  Parse an actions file in memory.
 *
 *                Passed linked list must have the "data" member
 *                zeroed, and must contain valid "next" and
 *                "unprocessed" fields.  The "raw" and "prefix"
 *                fields are ignored, and "type" is just overwritten.
 *
 *                Note that on error the file may have been
 *                partially parsed.
 *
 * Parameters  :
 *          1  :  file = Actions file to be parsed in-place.
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_PARSE  on error
 *
 *********************************************************************/
jb_err edit_parse_actions_file(struct editable_file * file)
{
   struct file_line * cur_line;
   size_t len;
   const char * text; /* Text from a line */
   char * name;  /* For lines of the form name=value */
   char * value; /* For lines of the form name=value */
   struct action_alias * alias_list = NULL;
   jb_err err = JB_ERR_OK;

   /* alias_list contains the aliases defined in this file.
    * It might be better to use the "file_line.data" fields
    * in the relavent places instead.
    */

   cur_line = file->lines;

   /* A note about blank line support: Blank lines should only
    * ever occur as the last line in the file.  This function
    * is more forgiving than that - FILE_LINE_BLANK can occur
    * anywhere.
    */

   /* Skip leading blanks.  Should only happen if file is
    * empty (which is valid, but pointless).
    */
   while ((cur_line != NULL)
       && (cur_line->unprocessed[0] == '\0'))
   {
      /* Blank line */
      cur_line->type = FILE_LINE_BLANK;
      cur_line = cur_line->next;
   }

   if ((cur_line != NULL)
    && (cur_line->unprocessed[0] != '{'))
   {
      /* File doesn't start with a header */
      file->parse_error = cur_line;
      file->parse_error_text = "First (non-comment) line of the file must contain a header.";
      return JB_ERR_PARSE;
   }

   if ((cur_line != NULL) && (0 ==
      match_actions_file_header_line(cur_line->unprocessed, "settings")))
   {
      cur_line->type = FILE_LINE_SETTINGS_HEADER;

      cur_line = cur_line->next;
      while ((cur_line != NULL) && (cur_line->unprocessed[0] != '{'))
      {
         if (cur_line->unprocessed[0])
         {
            cur_line->type = FILE_LINE_SETTINGS_ENTRY;

            err = split_line_on_equals(cur_line->unprocessed,
                     &cur_line->data.setting.name,
                     &cur_line->data.setting.svalue);
            if (err == JB_ERR_MEMORY)
            {
               return err;
            }
            else if (err != JB_ERR_OK)
            {
               /* Line does not contain a name=value pair */
               file->parse_error = cur_line;
               file->parse_error_text = "Expected a name=value pair on this {{description}} line, but couldn't find one.";
               return JB_ERR_PARSE;
            }
         }
         else
         {
            cur_line->type = FILE_LINE_BLANK;
         }
         cur_line = cur_line->next;
      }
   }

   if ((cur_line != NULL) && (0 ==
      match_actions_file_header_line(cur_line->unprocessed, "description")))
   {
      cur_line->type = FILE_LINE_DESCRIPTION_HEADER;

      cur_line = cur_line->next;
      while ((cur_line != NULL) && (cur_line->unprocessed[0] != '{'))
      {
         if (cur_line->unprocessed[0])
         {
            cur_line->type = FILE_LINE_DESCRIPTION_ENTRY;
         }
         else
         {
            cur_line->type = FILE_LINE_BLANK;
         }
         cur_line = cur_line->next;
      }
   }

   if ((cur_line != NULL) && (0 ==
      match_actions_file_header_line(cur_line->unprocessed, "alias")))
   {
      cur_line->type = FILE_LINE_ALIAS_HEADER;

      cur_line = cur_line->next;
      while ((cur_line != NULL) && (cur_line->unprocessed[0] != '{'))
      {
         if (cur_line->unprocessed[0])
         {
            /* define an alias */
            struct action_alias * new_alias;

            cur_line->type = FILE_LINE_ALIAS_ENTRY;

            err = split_line_on_equals(cur_line->unprocessed, &name, &value);
            if (err == JB_ERR_MEMORY)
            {
               free_alias_list(alias_list);
               return err;
            }
            else if (err != JB_ERR_OK)
            {
               /* Line does not contain a name=value pair */
               file->parse_error = cur_line;
               file->parse_error_text = "Expected a name=value pair on this {{alias}} line, but couldn't find one.";
               free_alias_list(alias_list);
               return JB_ERR_PARSE;
            }

            new_alias = zalloc_or_die(sizeof(*new_alias));

            err = get_actions(value, alias_list, new_alias->action);
            if (err)
            {
               /* Invalid action or out of memory */
               free(name);
               free(value);
               free(new_alias);
               free_alias_list(alias_list);
               if (err == JB_ERR_MEMORY)
               {
                  return err;
               }
               else
               {
                  /* Line does not contain a name=value pair */
                  file->parse_error = cur_line;
                  file->parse_error_text = "This alias does not specify a valid set of actions.";
                  return JB_ERR_PARSE;
               }
            }

            free(value);

            new_alias->name = name;

            /* add to list */
            new_alias->next = alias_list;
            alias_list = new_alias;
         }
         else
         {
            cur_line->type = FILE_LINE_BLANK;
         }
         cur_line = cur_line->next;
      }
   }

   /* Header done, process the main part of the file */
   while (cur_line != NULL)
   {
      /* At this point, (cur_line->unprocessed[0] == '{') */
      assert(cur_line->unprocessed[0] == '{');
      text = cur_line->unprocessed + 1;
      len = strlen(text) - 1;
      if (text[len] != '}')
      {
         /* No closing } on header */
         free_alias_list(alias_list);
         file->parse_error = cur_line;
         file->parse_error_text = "Headers starting with '{' must have a "
            "closing bracket ('}').  Headers starting with two brackets ('{{') "
            "must close with two brackets ('}}').";
         return JB_ERR_PARSE;
      }

      if (text[0] == '{')
      {
         /* An invalid {{ header.  */
         free_alias_list(alias_list);
         file->parse_error = cur_line;
         file->parse_error_text = "Unknown or unexpected two-bracket header.  "
            "Please remember that the system (two-bracket) headers must "
            "appear in the order {{settings}}, {{description}}, {{alias}}, "
            "and must appear before any actions (one-bracket) headers.  "
            "Also note that system headers may not be repeated.";
         return JB_ERR_PARSE;
      }

      while ((*text == ' ') || (*text == '\t'))
      {
         text++;
         len--;
      }
      while ((len > (size_t)0)
           && ((text[len - 1] == ' ')
            || (text[len - 1] == '\t')))
      {
         len--;
      }

      cur_line->type = FILE_LINE_ACTION;

      /* Remove {} and make copy */
      value = malloc_or_die(len + 1);
      strncpy(value, text, len);
      value[len] = '\0';

      /* Get actions */
      err = get_actions(value, alias_list, cur_line->data.action);
      if (err)
      {
         /* Invalid action or out of memory */
         free(value);
         free_alias_list(alias_list);
         if (err == JB_ERR_MEMORY)
         {
            return err;
         }
         else
         {
            /* Line does not contain a name=value pair */
            file->parse_error = cur_line;
            file->parse_error_text = "This header does not specify a valid set of actions.";
            return JB_ERR_PARSE;
         }
      }

      /* Done with string - it was clobbered anyway */
      free(value);

      /* Process next line */
      cur_line = cur_line->next;

      /* Loop processing URL patterns */
      while ((cur_line != NULL) && (cur_line->unprocessed[0] != '{'))
      {
         if (cur_line->unprocessed[0])
         {
            /* Could parse URL here, but this isn't currently needed */

            cur_line->type = FILE_LINE_URL;
         }
         else
         {
            cur_line->type = FILE_LINE_BLANK;
         }
         cur_line = cur_line->next;
      }
   } /* End main while(cur_line != NULL) loop */

   free_alias_list(alias_list);

   return JB_ERR_OK;
}


/*********************************************************************
 *
 * Function    :  edit_read_file_lines
 *
 * Description :  Read all the lines of a file into memory.
 *                Handles whitespace, comments and line continuation.
 *
 * Parameters  :
 *          1  :  fp = File to read from.  On return, this will be
 *                     at EOF but it will not have been closed.
 *          2  :  pfile = Destination for a linked list of file_lines.
 *                        Will be set to NULL on error.
 *          3  :  newline = How to handle newlines.
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *
 *********************************************************************/
jb_err edit_read_file_lines(FILE *fp, struct file_line ** pfile, int *newline)
{
   struct file_line * first_line; /* Keep for return value or to free */
   struct file_line * cur_line;   /* Current line */
   struct file_line * prev_line;  /* Entry with prev_line->next = cur_line */
   jb_err rval;

   assert(fp);
   assert(pfile);

   *pfile = NULL;

   cur_line = first_line = zalloc_or_die(sizeof(struct file_line));

   cur_line->type = FILE_LINE_UNPROCESSED;

   rval = edit_read_line(fp, &cur_line->raw, &cur_line->prefix, &cur_line->unprocessed, newline, NULL);
   if (rval)
   {
      /* Out of memory or empty file. */
      /* Note that empty file is not an error we propagate up */
      free(cur_line);
      return ((rval == JB_ERR_FILE) ? JB_ERR_OK : rval);
   }

   do
   {
      prev_line = cur_line;
      cur_line = prev_line->next = zalloc_or_die(sizeof(struct file_line));

      cur_line->type = FILE_LINE_UNPROCESSED;

      rval = edit_read_line(fp, &cur_line->raw, &cur_line->prefix, &cur_line->unprocessed, newline, NULL);
      if ((rval != JB_ERR_OK) && (rval != JB_ERR_FILE))
      {
         /* Out of memory */
         edit_free_file_lines(first_line);
         return JB_ERR_MEMORY;
      }

   }
   while (rval != JB_ERR_FILE);

   /* EOF */

   /* We allocated one too many - free it */
   prev_line->next = NULL;
   free(cur_line);

   *pfile = first_line;
   return JB_ERR_OK;
}


/*********************************************************************
 *
 * Function    :  edit_read_file
 *
 * Description :  Read a complete file into memory.
 *                Handles CGI parameter parsing.  If requested, also
 *                checks the file's modification timestamp.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  parameters = map of cgi parameters.
 *          3  :  require_version = true to check "ver" parameter.
 *          4  :  pfile = Destination for the file.  Will be set
 *                        to NULL on error.
 *
 * CGI Parameters :
 *           f :  The action file identifier.
 *         ver :  (Only if require_version is nonzero)
 *                Timestamp of the actions file.  If wrong, this
 *                function fails with JB_ERR_MODIFIED.
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if "filename" was not specified
 *                                  or is not valid.
 *                JB_ERR_FILE   if the file cannot be opened or
 *                              contains no data
 *                JB_ERR_MODIFIED if version checking was requested and
 *                                failed - the file was modified outside
 *                                of this CGI editor instance.
 *
 *********************************************************************/
jb_err edit_read_file(struct client_state *csp,
                      const struct map *parameters,
                      int require_version,
                      struct editable_file **pfile)
{
   struct file_line * lines;
   FILE * fp;
   jb_err err;
   const char *filename = NULL;
   struct editable_file * file;
   unsigned version = 0;
   struct stat statbuf[1];
   char version_buf[22];
   int newline = NEWLINE_UNKNOWN;
   unsigned i;

   assert(csp);
   assert(parameters);
   assert(pfile);

   *pfile = NULL;

   err = get_number_param(csp, parameters, "f", &i);
   if ((JB_ERR_OK == err) && (i < MAX_AF_FILES) && (NULL != csp->config->actions_file[i]))
   {
      filename = csp->config->actions_file[i];
   }
   else if (JB_ERR_CGI_PARAMS == err)
   {
      /*
       * Probably an old-school URL like
       * http://config.privoxy.org/edit-actions-list?f=default
       */
      get_file_name_param(csp, parameters, "f", &filename);
   }

   if (NULL == filename || stat(filename, statbuf) < 0)
   {
      /* Error, probably file not found. */
      return JB_ERR_FILE;
   }
   version = (unsigned) statbuf->st_mtime;

   if (require_version)
   {
      unsigned specified_version;
      err = get_number_param(csp, parameters, "v", &specified_version);
      if (err)
      {
         return err;
      }

      if (version != specified_version)
      {
         return JB_ERR_MODIFIED;
      }
   }

   if (NULL == (fp = fopen(filename,"rb")))
   {
      return JB_ERR_FILE;
   }

   err = edit_read_file_lines(fp, &lines, &newline);

   fclose(fp);

   if (err)
   {
      return err;
   }

   file = zalloc_or_die(sizeof(*file));

   file->lines = lines;
   file->newline = newline;
   file->filename = filename;
   file->version = version;
   file->identifier = i;

   /* Correct file->version_str */
   freez(file->version_str);
   snprintf(version_buf, sizeof(version_buf), "%u", file->version);
   version_buf[sizeof(version_buf)-1] = '\0';
   file->version_str = strdup_or_die(version_buf);

   *pfile = file;
   return JB_ERR_OK;
}


/*********************************************************************
 *
 * Function    :  edit_read_actions_file
 *
 * Description :  Read a complete actions file into memory.
 *                Handles CGI parameter parsing.  If requested, also
 *                checks the file's modification timestamp.
 *
 *                If this function detects an error in the categories
 *                JB_ERR_FILE, JB_ERR_MODIFIED, or JB_ERR_PARSE,
 *                then it handles it by filling in the specified
 *                response structure and returning JB_ERR_FILE.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = HTTP response.  Only filled in on error.
 *          2  :  parameters = map of cgi parameters.
 *          3  :  require_version = true to check "ver" parameter.
 *          4  :  pfile = Destination for the file.  Will be set
 *                        to NULL on error.
 *
 * CGI Parameters :
 *           f :  The actions file identifier.
 *         ver :  (Only if require_version is nonzero)
 *                Timestamp of the actions file.  If wrong, this
 *                function fails with JB_ERR_MODIFIED.
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if "filename" was not specified
 *                                  or is not valid.
 *                JB_ERR_FILE  if the file does not contain valid data,
 *                             or if file cannot be opened or
 *                             contains no data, or if version
 *                             checking was requested and failed.
 *
 *********************************************************************/
jb_err edit_read_actions_file(struct client_state *csp,
                              struct http_response *rsp,
                              const struct map *parameters,
                              int require_version,
                              struct editable_file **pfile)
{
   jb_err err;
   struct editable_file *file;
   static int acceptable_failures = ACCEPTABLE_TIMESTAMP_MISMATCHES - 1;

   assert(csp);
   assert(parameters);
   assert(pfile);

   *pfile = NULL;

   err = edit_read_file(csp, parameters, require_version, &file);
   if (err)
   {
      /* Try to handle if possible */
      if (err == JB_ERR_FILE)
      {
         err = cgi_error_file(csp, rsp, lookup(parameters, "f"));
      }
      else if (err == JB_ERR_MODIFIED)
      {
         assert(require_version);
         err = cgi_error_modified(csp, rsp, lookup(parameters, "f"));
         log_error(LOG_LEVEL_ERROR,
            "Blocking CGI edit request due to modification time mismatch.");
         if (acceptable_failures > 0)
         {
            log_error(LOG_LEVEL_INFO,
               "The CGI editor will be turned off after another %d mismatche(s).",
               acceptable_failures);
            acceptable_failures--;
         }
         else
         {
            log_error(LOG_LEVEL_INFO,
               "Timestamp mismatch limit reached, turning CGI editor off. "
               "Reload the configuration file to re-enable it.");
            csp->config->feature_flags &= ~RUNTIME_FEATURE_CGI_EDIT_ACTIONS;
         }
      }
      if (err == JB_ERR_OK)
      {
         /*
          * Signal to higher-level CGI code that there was a problem but we
          * handled it, they should just return JB_ERR_OK.
          */
         err = JB_ERR_FILE;
      }
      return err;
   }

   err = edit_parse_actions_file(file);
   if (err)
   {
      if (err == JB_ERR_PARSE)
      {
         err = cgi_error_parse(csp, rsp, file);
         if (err == JB_ERR_OK)
         {
            /*
             * Signal to higher-level CGI code that there was a problem but we
             * handled it, they should just return JB_ERR_OK.
             */
            err = JB_ERR_FILE;
         }
      }
      edit_free_file(file);
      return err;
   }

   *pfile = file;
   return JB_ERR_OK;
}


/*********************************************************************
 *
 * Function    :  get_file_name_param
 *
 * Description :  Get the name of the file to edit from the parameters
 *                passed to a CGI function using the old syntax.
 *                This function handles security checks and only
 *                accepts files that Privoxy already knows.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  parameters = map of cgi parameters
 *          3  :  param_name = The name of the parameter to read
 *          4  :  pfilename = pointer to the filename in
 *                csp->config->actions_file[] if found. Set to NULL on error.
 *
 * Returns     :  JB_ERR_OK         on success
 *                JB_ERR_MEMORY     on out-of-memory
 *                JB_ERR_CGI_PARAMS if "filename" was not specified
 *                                  or is not valid.
 *
 *********************************************************************/
static jb_err get_file_name_param(struct client_state *csp,
                                  const struct map *parameters,
                                  const char *param_name,
                                  const char **pfilename)
{
   const char *param;
   const char suffix[] = ".action";
   const char *s;
   char *name;
   char *fullpath;
   char ch;
   size_t len;
   size_t name_size;
   int i;

   assert(csp);
   assert(parameters);
   assert(pfilename);

   *pfilename = NULL;

   param = lookup(parameters, param_name);
   if (!*param)
   {
      return JB_ERR_CGI_PARAMS;
   }

   len = strlen(param);
   if (len >= FILENAME_MAX)
   {
      /* Too long. */
      return JB_ERR_CGI_PARAMS;
   }

   /*
    * Check every character to see if it's legal.
    * Totally unnecessary but we do it anyway.
    */
   s = param;
   while ((ch = *s++) != '\0')
   {
      if ( ((ch < 'A') || (ch > 'Z'))
        && ((ch < 'a') || (ch > 'z'))
        && ((ch < '0') || (ch > '9'))
        && (ch != '-')
        && (ch != '_'))
      {
         /* Probable hack attempt. */
         return JB_ERR_CGI_PARAMS;
      }
   }

   /* Append extension */
   name_size = len + strlen(suffix) + 1;
   name = malloc_or_die(name_size);
   strlcpy(name, param, name_size);
   strlcat(name, suffix, name_size);

   /* Prepend path */
   fullpath = make_path(csp->config->confdir, name);
   free(name);

   if (fullpath == NULL)
   {
      return JB_ERR_MEMORY;
   }

   /* Check if the file is known */
   for (i = 0; i < MAX_AF_FILES; i++)
   {
      if (NULL != csp->config->actions_file[i] &&
          !strcmp(fullpath, csp->config->actions_file[i]))
      {
         /* Success */
         *pfilename = csp->config->actions_file[i];
         freez(fullpath);

         return JB_ERR_OK;
      }
   }
   freez(fullpath);

   return JB_ERR_CGI_PARAMS;
}


/*********************************************************************
 *
 * Function    :  get_url_spec_param
 *
 * Description :  Get a URL pattern from the parameters
 *                passed to a CGI function.  Removes leading/trailing
 *                spaces and validates it.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  parameters = map of cgi parameters
 *          3  :  name = Name of CGI parameter to read
 *          4  :  pvalue = destination for value.  Will be malloc()'d.
 *                         Set to NULL on error.
 *
 * Returns     :  JB_ERR_OK         on success
 *                JB_ERR_MEMORY     on out-of-memory
 *                JB_ERR_CGI_PARAMS if the parameter was not specified
 *                                  or is not valid.
 *
 *********************************************************************/
static jb_err get_url_spec_param(struct client_state *csp,
                                 const struct map *parameters,
                                 const char *name,
                                 char **pvalue)
{
   const char *orig_param;
   char *param;
   char *s;
   struct pattern_spec compiled[1];
   jb_err err;

   assert(csp);
   assert(parameters);
   assert(name);
   assert(pvalue);

   *pvalue = NULL;

   orig_param = lookup(parameters, name);
   if (!*orig_param)
   {
      return JB_ERR_CGI_PARAMS;
   }

   /* Copy and trim whitespace */
   param = strdup(orig_param);
   if (param == NULL)
   {
      return JB_ERR_MEMORY;
   }
   chomp(param);

   /* Must be non-empty, and can't allow 1st character to be '{' */
   if (param[0] == '\0' || param[0] == '{')
   {
      free(param);
      return JB_ERR_CGI_PARAMS;
   }

   /* Check for embedded newlines */
   for (s = param; *s != '\0'; s++)
   {
      if ((*s == '\r') || (*s == '\n'))
      {
         free(param);
         return JB_ERR_CGI_PARAMS;
      }
   }

   /* Check that regex is valid */
   s = strdup(param);
   if (s == NULL)
   {
      free(param);
      return JB_ERR_MEMORY;
   }
   err = create_pattern_spec(compiled, s);
   free(s);
   if (err)
   {
      free(param);
      return (err == JB_ERR_MEMORY) ? JB_ERR_MEMORY : JB_ERR_CGI_PARAMS;
   }
   free_pattern_spec(compiled);

   if (param[strlen(param) - 1] == '\\')
   {
      /*
       * Must protect trailing '\\' from becoming line continuation character.
       * Two methods: 1) If it's a domain only, add a trailing '/'.
       * 2) For path, add the do-nothing PCRE expression (?:) to the end
       */
      if (strchr(param, '/') == NULL)
      {
         err = string_append(&param, "/");
      }
      else
      {
         err = string_append(&param, "(?:)");
      }
      if (err)
      {
         return err;
      }

      /* Check that the modified regex is valid */
      s = strdup(param);
      if (s == NULL)
      {
         free(param);
         return JB_ERR_MEMORY;
      }
      err = create_pattern_spec(compiled, s);
      free(s);
      if (err)
      {
         free(param);
         return (err == JB_ERR_MEMORY) ? JB_ERR_MEMORY : JB_ERR_CGI_PARAMS;
      }
      free_pattern_spec(compiled);
   }

   *pvalue = param;
   return JB_ERR_OK;
}

/*********************************************************************
 *
 * Function    :  map_radio
 *
 * Description :  Map a set of radio button values.  E.g. if you have
 *                3 radio buttons, declare them as:
 *                  <option type="radio" name="xyz" @xyz-a@>
 *                  <option type="radio" name="xyz" @xyz-b@>
 *                  <option type="radio" name="xyz" @xyz-c@>
 *                Then map one of the @xyz-?@ variables to "checked"
 *                and all the others to empty by calling:
 *                map_radio(exports, "xyz", "abc", sel)
 *                Where 'sel' is 'a', 'b', or 'c'.
 *
 * Parameters  :
 *          1  :  exports = Exports map to modify.
 *          2  :  optionname = name for map
 *          3  :  values = null-terminated list of values;
 *          4  :  value = Selected value.
 *
 * CGI Parameters : None
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *
 *********************************************************************/
static jb_err map_radio(struct map * exports,
                        const char * optionname,
                        const char * values,
                        int value)
{
   char * buf;
   char * p;
   char c;
   const size_t len = strlen(optionname);
   const size_t buf_size = len + 3;

   assert(exports);
   assert(optionname);
   assert(values);

   buf = malloc_or_die(buf_size);

   strlcpy(buf, optionname, buf_size);

   /* XXX: this looks ... interesting */
   p = buf + len;
   *p++ = '-';
   p[1] = '\0';

   while ((c = *values++) != '\0')
   {
      if (c != value)
      {
         *p = c;
         if (map(exports, buf, 1, "", 1))
         {
            return JB_ERR_MEMORY;
         }
      }
   }

   *p = (char)value;
   return map(exports, buf, 0, "checked", 1);
}


/*********************************************************************
 *
 * Function    :  cgi_error_modified
 *
 * Description :  CGI function that is called when a file is modified
 *                outside the CGI editor.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  filename = The file that was modified.
 *
 * CGI Parameters : none
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory error.
 *
 *********************************************************************/
jb_err cgi_error_modified(struct client_state *csp,
                          struct http_response *rsp,
                          const char *filename)
{
   struct map *exports;
   jb_err err;

   assert(csp);
   assert(rsp);
   assert(filename);

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      return JB_ERR_MEMORY;
   }

   err = map(exports, "f", 1, html_encode(filename), 0);
   if (err)
   {
      free_map(exports);
      return err;
   }

   return template_fill_for_cgi(csp, "cgi-error-modified", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  cgi_error_parse
 *
 * Description :  CGI function that is called when a file cannot
 *                be parsed by the CGI editor.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  file = The file that was modified.
 *
 * CGI Parameters : none
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory error.
 *
 *********************************************************************/
jb_err cgi_error_parse(struct client_state *csp,
                       struct http_response *rsp,
                       struct editable_file *file)
{
   struct map *exports;
   jb_err err;
   struct file_line *cur_line;

   assert(csp);
   assert(rsp);
   assert(file);

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      return JB_ERR_MEMORY;
   }

   err = map(exports, "f", 1, stringify(file->identifier), 0);
   if (!err) err = map(exports, "parse-error", 1, html_encode(file->parse_error_text), 0);

   cur_line = file->parse_error;
   assert(cur_line);

   if (!err) err = map(exports, "line-raw", 1, html_encode(cur_line->raw), 0);
   if (!err) err = map(exports, "line-data", 1, html_encode(cur_line->unprocessed), 0);

   if (err)
   {
      free_map(exports);
      return err;
   }

   return template_fill_for_cgi(csp, "cgi-error-parse", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  cgi_error_file
 *
 * Description :  CGI function that is called when a file cannot be
 *                opened by the CGI editor.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  filename = The file that was modified.
 *
 * CGI Parameters : none
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory error.
 *
 *********************************************************************/
jb_err cgi_error_file(struct client_state *csp,
                      struct http_response *rsp,
                      const char *filename)
{
   struct map *exports;
   jb_err err;

   assert(csp);
   assert(rsp);
   assert(filename);

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      return JB_ERR_MEMORY;
   }

   err = map(exports, "f", 1, html_encode(filename), 0);
   if (err)
   {
      free_map(exports);
      return err;
   }

   return template_fill_for_cgi(csp, "cgi-error-file", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  cgi_error_file_read_only
 *
 * Description :  CGI function that is called when a file cannot be
 *                opened for writing by the CGI editor.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  filename = The file that we can't write to
 *
 * CGI Parameters : none
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory error.
 *
 *********************************************************************/
jb_err cgi_error_file_read_only(struct client_state *csp,
                                struct http_response *rsp,
                                const char *filename)
{
   struct map *exports;
   jb_err err;

   assert(csp);
   assert(rsp);
   assert(filename);

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      return JB_ERR_MEMORY;
   }

   err = map(exports, "f", 1, html_encode(filename), 0);
   if (err)
   {
      free_map(exports);
      return err;
   }

   return template_fill_for_cgi(csp, "cgi-error-file-read-only", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions
 *
 * Description :  CGI function that allows the user to choose which
 *                actions file to edit.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters : None
 *
 * Returns     :  JB_ERR_OK on success
 *                JB_ERR_MEMORY on out-of-memory error
 *
 *********************************************************************/
jb_err cgi_edit_actions(struct client_state *csp,
                        struct http_response *rsp,
                        const struct map *parameters)
{
   (void)parameters;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   /* FIXME: Incomplete */

   return cgi_redirect(rsp, CGI_PREFIX "edit-actions-list?f=default");

}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_list
 *
 * Description :  CGI function that edits the actions list.
 *                FIXME: This function shouldn't FATAL ever.
 *                FIXME: This function doesn't check the retval of map()
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters : filename
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_FILE   if the file cannot be opened or
 *                              contains no data
 *                JB_ERR_CGI_PARAMS if "filename" was not specified
 *                                  or is not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_list(struct client_state *csp,
                             struct http_response *rsp,
                             const struct map *parameters)
{
   char * section_template;
   char * url_template;
   char * sections;
   char * urls;
   char buf[150];
   char * s;
   struct map * exports;
   struct map * section_exports;
   struct map * url_exports;
   struct editable_file * file;
   struct file_line * cur_line;
   unsigned line_number = 0;
   unsigned prev_section_line_number = ((unsigned) (-1));
   int i, url_1_2;
   struct file_list * fl;
   struct url_actions * b;
   char * buttons = NULL;
   jb_err err;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      return JB_ERR_MEMORY;
   }

   /* Load actions file */
   err = edit_read_actions_file(csp, rsp, parameters, 0, &file);
   if (err)
   {
      /* No filename specified, can't read file, or out of memory. */
      free_map(exports);
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   /* Find start of actions in file */
   cur_line = file->lines;
   line_number = 1;
   while ((cur_line != NULL) && (cur_line->type != FILE_LINE_ACTION))
   {
      cur_line = cur_line->next;
      line_number++;
   }

   /*
    * Conventional actions files should have a match all block
    * at the start:
    * cur_line             = {...global actions...}
    * cur_line->next       = /
    * cur_line->next->next = {...actions...} or EOF
    */
   if ( (cur_line != NULL)
     && (cur_line->type == FILE_LINE_ACTION)
     && (cur_line->next != NULL)
     && (cur_line->next->type == FILE_LINE_URL)
     && (0 == strcmp(cur_line->next->unprocessed, "/"))
     && ( (cur_line->next->next == NULL)
       || (cur_line->next->next->type != FILE_LINE_URL)
      ) )
   {
      /*
       * Generate string with buttons to set actions for "/" to
       * any predefined set of actions (named standard.*, probably
       * residing in standard.action).
       */

      err = template_load(csp, &section_template, "edit-actions-list-button", 0);
      if (err)
      {
         edit_free_file(file);
         free_map(exports);
         if (err == JB_ERR_FILE)
         {
            return cgi_error_no_template(csp, rsp, "edit-actions-list-button");
         }
         return err;
      }

      err = template_fill(&section_template, exports);
      if (err)
      {
         edit_free_file(file);
         free_map(exports);
         return err;
      }

      buttons = strdup("");
      for (i = 0; i < MAX_AF_FILES; i++)
      {
         if (((fl = csp->actions_list[i]) != NULL) && ((b = fl->f) != NULL))
         {
            for (b = b->next; NULL != b; b = b->next)
            {
               if (!strncmp(b->url->spec, "standard.", 9) && *(b->url->spec + 9) != '\0')
               {
                  if (err)
                  {
                     freez(buttons);
                     free(section_template);
                     edit_free_file(file);
                     free_map(exports);
                     return JB_ERR_MEMORY;
                  }

                  section_exports = new_map();
                  err = map(section_exports, "button-name", 1, b->url->spec + 9, 1);

                  if (err || (NULL == (s = strdup(section_template))))
                  {
                     free_map(section_exports);
                     freez(buttons);
                     free(section_template);
                     edit_free_file(file);
                     free_map(exports);
                     return JB_ERR_MEMORY;
                  }

                  if (!err) err = template_fill(&s, section_exports);
                  free_map(section_exports);
                  if (!err) err = string_join(&buttons, s);
               }
            }
         }
      }
      freez(section_template);
      if (!err) err = map(exports, "all-urls-buttons", 1, buttons, 0);

      /*
       * Conventional actions file, supply extra editing help.
       * (e.g. don't allow them to make it an unconventional one).
       */
      if (!err) err = map_conditional(exports, "all-urls-present", 1);

      snprintf(buf, sizeof(buf), "%u", line_number);
      if (!err) err = map(exports, "all-urls-s", 1, buf, 1);
      snprintf(buf, sizeof(buf), "%u", line_number + 2);
      if (!err) err = map(exports, "all-urls-s-next", 1, buf, 1);
      if (!err) err = map(exports, "all-urls-actions", 1,
                          actions_to_html(csp, cur_line->data.action), 0);

       /* Skip the 2 lines */
      cur_line = cur_line->next->next;
      line_number += 2;

      /*
       * Note that prev_section_line_number is NOT set here.
       * This is deliberate and not a bug.  It stops a "Move up"
       * option appearing on the next section.  Clicking "Move
       * up" would make the actions file unconventional, which
       * we don't want, so we hide this option.
       */
   }
   else
   {
      /*
       * Non-standard actions file - does not begin with
       * the "All URLs" section.
       */
      if (!err) err = map_conditional(exports, "all-urls-present", 0);
   }

   /* Set up global exports */

   if (!err) err = map(exports, "actions-file", 1, html_encode(file->filename), 0);
   if (!err) err = map(exports, "f", 1, stringify(file->identifier), 0);
   if (!err) err = map(exports, "v", 1, file->version_str, 1);

   /* Discourage private additions to default.action */

   if (!err) err = map_conditional(exports, "default-action",
                                   (strstr("default.action", file->filename) != NULL));
   if (err)
   {
      edit_free_file(file);
      free_map(exports);
      return err;
   }

   /* Should do all global exports above this point */

   /* Load templates */

   err = template_load(csp, &section_template, "edit-actions-list-section", 0);
   if (err)
   {
      edit_free_file(file);
      free_map(exports);
      if (err == JB_ERR_FILE)
      {
         return cgi_error_no_template(csp, rsp, "edit-actions-list-section");
      }
      return err;
   }

   err = template_load(csp, &url_template, "edit-actions-list-url", 0);
   if (err)
   {
      free(section_template);
      edit_free_file(file);
      free_map(exports);
      if (err == JB_ERR_FILE)
      {
         return cgi_error_no_template(csp, rsp, "edit-actions-list-url");
      }
      return err;
   }

   err = template_fill(&section_template, exports);
   if (err)
   {
      free(url_template);
      edit_free_file(file);
      free_map(exports);
      return err;
   }

   err = template_fill(&url_template, exports);
   if (err)
   {
      free(section_template);
      edit_free_file(file);
      free_map(exports);
      return err;
   }

   if (NULL == (sections = strdup("")))
   {
      free(section_template);
      free(url_template);
      edit_free_file(file);
      free_map(exports);
      return JB_ERR_MEMORY;
   }

   while ((cur_line != NULL) && (cur_line->type == FILE_LINE_ACTION))
   {
      section_exports = new_map();

      snprintf(buf, sizeof(buf), "%u", line_number);
      err = map(section_exports, "s", 1, buf, 1);
      if (!err) err = map(section_exports, "actions", 1,
                          actions_to_html(csp, cur_line->data.action), 0);

      if ((!err)
        && (cur_line->next != NULL)
        && (cur_line->next->type == FILE_LINE_URL))
      {
         /* This section contains at least one URL, don't allow delete */
         err = map_block_killer(section_exports, "empty-section");
      }
      else
      {
         if (!err) err = map_block_keep(section_exports, "empty-section");
      }

      if (prev_section_line_number != ((unsigned)(-1)))
      {
         /* Not last section */
         snprintf(buf, sizeof(buf), "%u", prev_section_line_number);
         if (!err) err = map(section_exports, "s-prev", 1, buf, 1);
         if (!err) err = map_block_keep(section_exports, "s-prev-exists");
      }
      else
      {
         /* Last section */
         if (!err) err = map_block_killer(section_exports, "s-prev-exists");
      }
      prev_section_line_number = line_number;

      if (err)
      {
         free(sections);
         free(section_template);
         free(url_template);
         edit_free_file(file);
         free_map(exports);
         free_map(section_exports);
         return err;
      }

      /* Should do all section-specific exports above this point */

      if (NULL == (urls = strdup("")))
      {
         free(sections);
         free(section_template);
         free(url_template);
         edit_free_file(file);
         free_map(exports);
         free_map(section_exports);
         return JB_ERR_MEMORY;
      }

      url_1_2 = 2;

      cur_line = cur_line->next;
      line_number++;

      while ((cur_line != NULL) && (cur_line->type == FILE_LINE_URL))
      {
         url_exports = new_map();

         snprintf(buf, sizeof(buf), "%u", line_number);
         err = map(url_exports, "p", 1, buf, 1);

         snprintf(buf, sizeof(buf), "%d", url_1_2);
         if (!err) err = map(url_exports, "url-1-2", 1, buf, 1);

         if (!err) err = map(url_exports, "url-html", 1,
                             html_encode(cur_line->unprocessed), 0);
         if (!err) err = map(url_exports, "url", 1,
                             url_encode(cur_line->unprocessed), 0);

         if (err)
         {
            free(urls);
            free(sections);
            free(section_template);
            free(url_template);
            edit_free_file(file);
            free_map(exports);
            free_map(section_exports);
            free_map(url_exports);
            return err;
         }

         if (NULL == (s = strdup(url_template)))
         {
            free(urls);
            free(sections);
            free(section_template);
            free(url_template);
            edit_free_file(file);
            free_map(exports);
            free_map(section_exports);
            free_map(url_exports);
            return JB_ERR_MEMORY;
         }

         err = template_fill(&s, section_exports);
         if (!err) err = template_fill(&s, url_exports);
         if (!err) err = string_append(&urls, s);

         free_map(url_exports);
         freez(s);

         if (err)
         {
            freez(urls);
            free(sections);
            free(section_template);
            free(url_template);
            edit_free_file(file);
            free_map(exports);
            free_map(section_exports);
            return err;
         }

         url_1_2 = 3 - url_1_2;

         cur_line = cur_line->next;
         line_number++;
      }

      err = map(section_exports, "urls", 1, urls, 0);

      /* Could also do section-specific exports here, but it wouldn't be as fast */

      snprintf(buf, sizeof(buf), "%u", line_number);
      if (!err) err = map(section_exports, "s-next", 1, buf, 1);

      if ((cur_line != NULL)
       && (cur_line->type == FILE_LINE_ACTION))
      {
         /* Not last section */
         if (!err) err = map_block_keep(section_exports, "s-next-exists");
      }
      else
      {
         /* Last section */
         if (!err) err = map_block_killer(section_exports, "s-next-exists");
      }

      if (err)
      {
         free(sections);
         free(section_template);
         free(url_template);
         edit_free_file(file);
         free_map(exports);
         free_map(section_exports);
         return err;
      }

      if (NULL == (s = strdup(section_template)))
      {
         free(sections);
         free(section_template);
         free(url_template);
         edit_free_file(file);
         free_map(exports);
         free_map(section_exports);
         return JB_ERR_MEMORY;
      }

      err = template_fill(&s, section_exports);
      if (!err) err = string_append(&sections, s);

      freez(s);
      free_map(section_exports);

      if (err)
      {
         freez(sections);
         free(section_template);
         free(url_template);
         edit_free_file(file);
         free_map(exports);
         return err;
      }
   }

   edit_free_file(file);
   free(section_template);
   free(url_template);

   err = map(exports, "sections", 1, sections, 0);
   if (err)
   {
      free_map(exports);
      return err;
   }

   /* Could also do global exports here, but it wouldn't be as fast */

   return template_fill_for_cgi(csp, "edit-actions-list", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_for_url
 *
 * Description :  CGI function that edits the Actions list.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters : None
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_for_url(struct client_state *csp,
                                struct http_response *rsp,
                                const struct map *parameters)
{
   struct map * exports;
   unsigned sectionid;
   struct editable_file * file;
   struct file_line * cur_line;
   unsigned line_number;
   jb_err err;
   struct re_filterfile_spec *filter_group;
   int i, have_filters = 0;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "s", &sectionid);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   cur_line = file->lines;

   for (line_number = 1; (cur_line != NULL) && (line_number < sectionid); line_number++)
   {
      cur_line = cur_line->next;
   }

   if ( (cur_line == NULL)
     || (line_number != sectionid)
     || (sectionid < 1)
     || (cur_line->type != FILE_LINE_ACTION))
   {
      /* Invalid "sectionid" parameter */
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   if (NULL == (exports = default_exports(csp, NULL)))
   {
      edit_free_file(file);
      return JB_ERR_MEMORY;
   }

   err = map(exports, "f", 1, stringify(file->identifier), 0);
   if (!err) err = map(exports, "v", 1, file->version_str, 1);
   if (!err) err = map(exports, "s", 1, url_encode(lookup(parameters, "s")), 0);

   if (!err) err = actions_to_radio(exports, cur_line->data.action);

   /*
    * XXX: Some browsers (at least IE6 and IE7) have an artificial URL
    * length limitation and ignore clicks on the Submit buttons if
    * the resulting GET URL would be longer than their limit.
    *
    * In Privoxy 3.0.5 beta the standard edit-actions-for-url template
    * reached this limit and action editing stopped working in these
    * browsers (BR #1570678).
    *
    * The config option split-large-forms works around this browser
    * bug (HTTP has no URL length limitation) by deviding the action
    * list form into multiple smaller ones. It means the URLs are shorter
    * and work in broken browsers as well, but the user can no longer change
    * all actions with one submit.
    *
    * A better solution would be to switch to POST requests,
    * but this will do for now.
    */
   if (!err && (csp->config->feature_flags & RUNTIME_FEATURE_SPLIT_LARGE_FORMS))
   {
      /* Generate multiple smaller form by killing the big one. */
      err = map_block_killer(exports, "one-form-only");
   }
   else
   {
      /* Default: Generate one large form by killing the smaller ones. */
      err = map_block_killer(exports, "multiple-forms");
   }

   for (i = 0; i < MAX_AF_FILES; i++)
   {
      if ((csp->rlist[i] != NULL) && (csp->rlist[i]->f != NULL))
      {
         if (!err) err = map_conditional(exports, "any-filters-defined", 1);
         have_filters = 1;
         break;
      }
   }

#ifndef FEATURE_EXTERNAL_FILTERS
   if (!err) err = map_block_killer(exports, "external-content-filters");
#endif

   if (err)
   {
      edit_free_file(file);
      free_map(exports);
      return err;
   }

   if (0 == have_filters)
   {
      err = map(exports, "filter-params", 1, "", 1);
   }
   else
   {
      /*
       * List available filters and their settings.
       */
      char *filter_template;
      int filter_identifier = 0;
      char *prepared_templates[MAX_FILTER_TYPES];

      for (i = 0; i < MAX_FILTER_TYPES; i++)
      {
         prepared_templates[i] = strdup("");
      }

      err = template_load(csp, &filter_template, "edit-actions-for-url-filter", 0);
      if (err)
      {
         edit_free_file(file);
         free_map(exports);
         if (err == JB_ERR_FILE)
         {
            return cgi_error_no_template(csp, rsp, "edit-actions-for-url-filter");
         }
         return err;
      }

      err = template_fill(&filter_template, exports);

      for (i = 0; i < MAX_AF_FILES; i++)
      {
         if ((csp->rlist[i] != NULL) && (csp->rlist[i]->f != NULL))
         {
            filter_group = csp->rlist[i]->f;
            for (;(!err) && (filter_group != NULL); filter_group = filter_group->next)
            {
               char current_mode = 'x';
               char number[20];
               struct list_entry *filter_name;
               struct map *line_exports;
               const int type = filter_group->type;
               const int multi_action_index = filter_type_info[type].multi_action_index;

               assert(type < MAX_FILTER_TYPES);

               filter_name = cur_line->data.action->multi_add[multi_action_index]->first;
               while ((filter_name != NULL)
                   && (0 != strcmp(filter_group->name, filter_name->str)))
               {
                    filter_name = filter_name->next;
               }

               if (filter_name != NULL)
               {
                  current_mode = 'y';
               }
               else
               {
                  filter_name = cur_line->data.action->multi_remove[multi_action_index]->first;
                  while ((filter_name != NULL)
                      && (0 != strcmp(filter_group->name, filter_name->str)))
                  {
                       filter_name = filter_name->next;
                  }
                  if (filter_name != NULL)
                  {
                     current_mode = 'n';
                  }
               }

               /* Generate a unique serial number */
               snprintf(number, sizeof(number), "%x", filter_identifier++);
               number[sizeof(number) - 1] = '\0';

               line_exports = new_map();
               if (line_exports == NULL)
               {
                  err = JB_ERR_MEMORY;
               }
               else
               {
                  char *filter_line;

                  if (!err) err = map(line_exports, "index", 1, number, 1);
                  if (!err) err = map(line_exports, "name",  1, filter_group->name, 1);
                  if (!err) err = map(line_exports, "description",  1, filter_group->description, 1);
                  if (!err) err = map_radio(line_exports, "this-filter", "ynx", current_mode);
                  if (!err) err = map(line_exports, "filter-type", 1, filter_type_info[type].type, 1);
                  if (!err) err = map(line_exports, "abbr-filter-type", 1, filter_type_info[type].abbr_type, 1);
                  if (!err) err = map(line_exports, "anchor", 1, filter_type_info[type].anchor, 1);

                  if (!err)
                  {
                     filter_line = strdup(filter_template);
                     if (filter_line == NULL) err = JB_ERR_MEMORY;
                  }
                  if (!err) err = template_fill(&filter_line, line_exports);
                  string_join(&prepared_templates[type], filter_line);

                  free_map(line_exports);
               }
            }
         }
      }
      freez(filter_template);

      /* Replace all filter macros with the aggregated templates */
      for (i = 0; i < MAX_FILTER_TYPES; i++)
      {
         if (err) break;
         err = map(exports, filter_type_info[i].macro_name, 1, prepared_templates[i], 0);
      }

      if (err)
      {
         /* Free aggregated templates */
         for (i = 0; i < MAX_FILTER_TYPES; i++)
         {
            freez(prepared_templates[i]);
         }
      }
   }

   /* Check or uncheck the "disable all of this type" radio buttons. */
   for (i = 0; i < MAX_FILTER_TYPES; i++)
   {
      const int a = filter_type_info[i].multi_action_index;
      const int disable_all = cur_line->data.action->multi_remove_all[a];
      if (err) break;
      err = map_radio(exports, filter_type_info[i].disable_all_option, "nx", (disable_all ? 'n' : 'x'));
   }

   edit_free_file(file);

   if (err)
   {
      free_map(exports);
      return err;
   }

   return template_fill_for_cgi(csp, "edit-actions-for-url", exports, rsp);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_submit
 *
 * Description :  CGI function that actually edits the Actions list.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters : None
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_submit(struct client_state *csp,
                               struct http_response *rsp,
                               const struct map *parameters)
{
   unsigned sectionid;
   char * actiontext;
   char * newtext;
   size_t newtext_size;
   size_t len;
   struct editable_file * file;
   struct file_line * cur_line;
   unsigned line_number;
   char target[1024];
   jb_err err;
   int filter_identifier;
   int i;
   const char * action_set_name;
   struct file_list * fl;
   struct url_actions * b;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "s", &sectionid);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   cur_line = file->lines;

   for (line_number = 1; (cur_line != NULL) && (line_number < sectionid); line_number++)
   {
      cur_line = cur_line->next;
   }

   if ( (cur_line == NULL)
     || (line_number != sectionid)
     || (sectionid < 1)
     || (cur_line->type != FILE_LINE_ACTION))
   {
      /* Invalid "sectionid" parameter */
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   get_string_param(parameters, "p", &action_set_name);
   if (action_set_name != NULL)
   {
      for (filter_identifier = 0; filter_identifier < MAX_AF_FILES; filter_identifier++)
      {
         if (((fl = csp->actions_list[filter_identifier]) != NULL) && ((b = fl->f) != NULL))
         {
            for (b = b->next; NULL != b; b = b->next)
            {
               if (!strncmp(b->url->spec, "standard.", 9) && !strcmp(b->url->spec + 9, action_set_name))
               {
                  copy_action(cur_line->data.action, b->action);
                  goto found;
               }
            }
         }
      }
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;

      found: ;
   }
   else
   {
      err = actions_from_radio(parameters, cur_line->data.action);
   }

   if (err)
   {
      /* Out of memory */
      edit_free_file(file);
      return err;
   }

   /* Check the "disable all of this type" parameters. */
   for (i = 0; i < MAX_FILTER_TYPES; i++)
   {
      const int multi_action_index = filter_type_info[i].multi_action_index;
      const char ch = get_char_param(parameters, filter_type_info[i].disable_all_param);

      if (ch == 'N')
      {
         list_remove_all(cur_line->data.action->multi_add[multi_action_index]);
         list_remove_all(cur_line->data.action->multi_remove[multi_action_index]);
         cur_line->data.action->multi_remove_all[multi_action_index] = 1;
      }
      else if (ch == 'X')
      {
         cur_line->data.action->multi_remove_all[multi_action_index] = 0;
      }
   }

   for (filter_identifier = 0; !err; filter_identifier++)
   {
      char key_value[30];
      char key_name[30];
      char key_type[30];
      const char *name;
      char value; /*
                   * Filter state. Valid states are: 'Y' (active),
                   * 'N' (inactive) and 'X' (no change).
                   * XXX: bad name.
                   */
      char type;  /*
                   * Abbreviated filter type. Valid types are: 'F' (content filter),
                   * 'S' (server-header filter) and 'C' (client-header filter).
                   */
      int multi_action_index = 0;

      /* Generate the keys */
      snprintf(key_value, sizeof(key_value), "filter_r%x", filter_identifier);
      key_value[sizeof(key_value) - 1] = '\0'; /* XXX: Why? */
      snprintf(key_name, sizeof(key_name), "filter_n%x", filter_identifier);
      key_name[sizeof(key_name) - 1] = '\0'; /* XXX: Why? */
      snprintf(key_type, sizeof(key_type), "filter_t%x", filter_identifier);

      err = get_string_param(parameters, key_name, &name);
      if (err) break;

      if (name == NULL)
      {
         /* End of list */
         break;
      }

      type = get_char_param(parameters, key_type);
      switch (type)
      {
         case 'F':
            multi_action_index = ACTION_MULTI_FILTER;
            break;
         case 'S':
            multi_action_index = ACTION_MULTI_SERVER_HEADER_FILTER;
            break;
         case 'C':
            multi_action_index = ACTION_MULTI_CLIENT_HEADER_FILTER;
            break;
         case 'L':
            multi_action_index = ACTION_MULTI_CLIENT_HEADER_TAGGER;
            break;
         case 'E':
            multi_action_index = ACTION_MULTI_SERVER_HEADER_TAGGER;
            break;
         default:
            log_error(LOG_LEVEL_ERROR,
               "Unknown filter type: %c for filter %s. Filter ignored.", type, name);
            continue;
      }
      assert(multi_action_index);

      value = get_char_param(parameters, key_value);
      if (value == 'Y')
      {
         list_remove_item(cur_line->data.action->multi_add[multi_action_index], name);
         if (!err) err = enlist(cur_line->data.action->multi_add[multi_action_index], name);
         list_remove_item(cur_line->data.action->multi_remove[multi_action_index], name);
      }
      else if (value == 'N')
      {
         list_remove_item(cur_line->data.action->multi_add[multi_action_index], name);
         if (!cur_line->data.action->multi_remove_all[multi_action_index])
         {
            list_remove_item(cur_line->data.action->multi_remove[multi_action_index], name);
            if (!err) err = enlist(cur_line->data.action->multi_remove[multi_action_index], name);
         }
      }
      else if (value == 'X')
      {
         list_remove_item(cur_line->data.action->multi_add[multi_action_index], name);
         list_remove_item(cur_line->data.action->multi_remove[multi_action_index], name);
      }
   }

   if (err)
   {
      /* Out of memory */
      edit_free_file(file);
      return err;
   }

   if (NULL == (actiontext = actions_to_text(cur_line->data.action)))
   {
      /* Out of memory */
      edit_free_file(file);
      return JB_ERR_MEMORY;
   }

   len = strlen(actiontext);
   if (len == 0)
   {
      /*
       * Empty action - must special-case this.
       * Simply setting len to 1 is sufficient...
       */
      len = 1;
   }

   newtext_size = len + 2;
   newtext = malloc_or_die(newtext_size);
   strlcpy(newtext, actiontext, newtext_size);
   free(actiontext);
   newtext[0]       = '{';
   newtext[len]     = '}';
   newtext[len + 1] = '\0';

   freez(cur_line->raw);
   freez(cur_line->unprocessed);
   cur_line->unprocessed = newtext;

   err = edit_write_file(file);
   if (err)
   {
      /* Error writing file */
      if (err == JB_ERR_FILE)
      {
         /* Read-only file. */
         err = cgi_error_file_read_only(csp, rsp, file->filename);
      }
      edit_free_file(file);
      return err;
   }

   snprintf(target, sizeof(target), CGI_PREFIX "edit-actions-list?foo=%lu&f=%i#l%u",
            (long) time(NULL), file->identifier, sectionid);

   edit_free_file(file);

   return cgi_redirect(rsp, target);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_url
 *
 * Description :  CGI function that actually edits a URL pattern in
 *                an actions file.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *    filename : Identifies the file to edit
 *         ver : File's last-modified time
 *     section : Line number of section to edit
 *     pattern : Line number of pattern to edit
 *      newval : New value for pattern
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_url(struct client_state *csp,
                            struct http_response *rsp,
                            const struct map *parameters)
{
   unsigned patternid;
   char * new_pattern;
   struct editable_file * file;
   struct file_line * cur_line;
   unsigned line_number;
   unsigned section_start_line_number = 0;
   char target[1024];
   jb_err err;

   assert(csp);
   assert(rsp);
   assert(parameters);

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "p", &patternid);
   if (err)
   {
      return err;
   }
   if (patternid < 1U)
   {
      return JB_ERR_CGI_PARAMS;
   }

   err = get_url_spec_param(csp, parameters, "u", &new_pattern);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      free(new_pattern);
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   line_number = 1;
   cur_line = file->lines;

   while ((cur_line != NULL) && (line_number < patternid))
   {
      if (cur_line->type == FILE_LINE_ACTION)
      {
         section_start_line_number = line_number;
      }
      cur_line = cur_line->next;
      line_number++;
   }

   if ((cur_line == NULL)
    || (cur_line->type != FILE_LINE_URL))
   {
      /* Invalid "patternid" parameter */
      free(new_pattern);
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   /* At this point, the line to edit is in cur_line */

   freez(cur_line->raw);
   freez(cur_line->unprocessed);
   cur_line->unprocessed = new_pattern;

   err = edit_write_file(file);
   if (err)
   {
      /* Error writing file */
      if (err == JB_ERR_FILE)
      {
         /* Read-only file. */
         err = cgi_error_file_read_only(csp, rsp, file->filename);
      }
      edit_free_file(file);
      return err;
   }

   snprintf(target, sizeof(target), CGI_PREFIX "edit-actions-list?foo=%lu&f=%i#l%u",
            (long) time(NULL), file->identifier, section_start_line_number);

   edit_free_file(file);

   return cgi_redirect(rsp, target);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_add_url
 *
 * Description :  CGI function that actually adds a URL pattern to
 *                an actions file.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *    filename : Identifies the file to edit
 *         ver : File's last-modified time
 *     section : Line number of section to edit
 *      newval : New pattern
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_add_url(struct client_state *csp,
                                struct http_response *rsp,
                                const struct map *parameters)
{
   unsigned sectionid;
   char * new_pattern;
   struct file_line * new_line;
   struct editable_file * file;
   struct file_line * cur_line;
   unsigned line_number;
   char target[1024];
   jb_err err;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "s", &sectionid);
   if (err)
   {
      return err;
   }
   if (sectionid < 1U)
   {
      return JB_ERR_CGI_PARAMS;
   }

   err = get_url_spec_param(csp, parameters, "u", &new_pattern);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      free(new_pattern);
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   line_number = 1;
   cur_line = file->lines;

   while ((cur_line != NULL) && (line_number < sectionid))
   {
      cur_line = cur_line->next;
      line_number++;
   }

   if ((cur_line == NULL)
    || (cur_line->type != FILE_LINE_ACTION))
   {
      /* Invalid "sectionid" parameter */
      free(new_pattern);
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   /* At this point, the section header is in cur_line - add after this. */

   /* Allocate the new line */
   new_line = zalloc_or_die(sizeof(*new_line));

   /* Fill in the data members of the new line */
   new_line->raw = NULL;
   new_line->prefix = NULL;
   new_line->unprocessed = new_pattern;
   new_line->type = FILE_LINE_URL;

   /* Link new_line into the list, after cur_line */
   new_line->next = cur_line->next;
   cur_line->next = new_line;

   /* Done making changes, now commit */

   err = edit_write_file(file);
   if (err)
   {
      /* Error writing file */
      if (err == JB_ERR_FILE)
      {
         /* Read-only file. */
         err = cgi_error_file_read_only(csp, rsp, file->filename);
      }
      edit_free_file(file);
      return err;
   }

   snprintf(target, sizeof(target), CGI_PREFIX "edit-actions-list?foo=%lu&f=%i#l%u",
            (long) time(NULL), file->identifier, sectionid);

   edit_free_file(file);

   return cgi_redirect(rsp, target);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_remove_url
 *
 * Description :  CGI function that actually removes a URL pattern from
 *                the actions file.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *           f : (filename) Identifies the file to edit
 *           v : (version) File's last-modified time
 *           p : (pattern) Line number of pattern to remove
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_remove_url(struct client_state *csp,
                                   struct http_response *rsp,
                                   const struct map *parameters)
{
   unsigned patternid;
   struct editable_file * file;
   struct file_line * cur_line;
   struct file_line * prev_line;
   unsigned line_number;
   unsigned section_start_line_number = 0;
   char target[1024];
   jb_err err;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "p", &patternid);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   line_number = 1;
   prev_line = NULL;
   cur_line = file->lines;

   while ((cur_line != NULL) && (line_number < patternid))
   {
      if (cur_line->type == FILE_LINE_ACTION)
      {
         section_start_line_number = line_number;
      }
      prev_line = cur_line;
      cur_line = cur_line->next;
      line_number++;
   }

   if ( (cur_line == NULL)
     || (prev_line == NULL)
     || (cur_line->type != FILE_LINE_URL))
   {
      /* Invalid "patternid" parameter */
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   /* At this point, the line to remove is in cur_line, and the previous
    * one is in prev_line
    */

   /* Unlink cur_line */
   prev_line->next = cur_line->next;
   cur_line->next = NULL;

   /* Free cur_line */
   edit_free_file_lines(cur_line);

   err = edit_write_file(file);
   if (err)
   {
      /* Error writing file */
      if (err == JB_ERR_FILE)
      {
         /* Read-only file. */
         err = cgi_error_file_read_only(csp, rsp, file->filename);
      }
      edit_free_file(file);
      return err;
   }

   snprintf(target, sizeof(target), CGI_PREFIX "edit-actions-list?foo=%lu&f=%u#l%u",
            (long) time(NULL), file->identifier, section_start_line_number);

   edit_free_file(file);

   return cgi_redirect(rsp, target);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_section_remove
 *
 * Description :  CGI function that actually removes a whole section from
 *                the actions file.  The section must be empty first
 *                (else JB_ERR_CGI_PARAMS).
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *           f : (filename) Identifies the file to edit
 *           v : (version) File's last-modified time
 *           s : (section) Line number of section to edit
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_section_remove(struct client_state *csp,
                                       struct http_response *rsp,
                                       const struct map *parameters)
{
   unsigned sectionid;
   struct editable_file * file;
   struct file_line * cur_line;
   struct file_line * prev_line;
   unsigned line_number;
   char target[1024];
   jb_err err;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "s", &sectionid);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   line_number = 1;
   cur_line = file->lines;

   prev_line = NULL;
   while ((cur_line != NULL) && (line_number < sectionid))
   {
      prev_line = cur_line;
      cur_line = cur_line->next;
      line_number++;
   }

   if ((cur_line == NULL)
    || (cur_line->type != FILE_LINE_ACTION))
   {
      /* Invalid "sectionid" parameter */
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   if ((cur_line->next != NULL)
    && (cur_line->next->type == FILE_LINE_URL))
   {
      /* Section not empty. */
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   /* At this point, the line to remove is in cur_line, and the previous
    * one is in prev_line
    */

   /* Unlink cur_line */
   if (prev_line == NULL)
   {
      /* Removing the first line from the file */
      file->lines = cur_line->next;
   }
   else
   {
      prev_line->next = cur_line->next;
   }
   cur_line->next = NULL;

   /* Free cur_line */
   edit_free_file_lines(cur_line);

   err = edit_write_file(file);
   if (err)
   {
      /* Error writing file */
      if (err == JB_ERR_FILE)
      {
         /* Read-only file. */
         err = cgi_error_file_read_only(csp, rsp, file->filename);
      }
      edit_free_file(file);
      return err;
   }

   snprintf(target, sizeof(target), CGI_PREFIX "edit-actions-list?foo=%lu&f=%u",
            (long) time(NULL), file->identifier);

   edit_free_file(file);

   return cgi_redirect(rsp, target);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_section_add
 *
 * Description :  CGI function that adds a new empty section to
 *                an actions file.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *           f : (filename) Identifies the file to edit
 *           v : (version) File's last-modified time
 *           s : (section) Line number of section to add after, 0 for
 *               start of file.
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_section_add(struct client_state *csp,
                                    struct http_response *rsp,
                                    const struct map *parameters)
{
   unsigned sectionid;
   struct file_line * new_line;
   char * new_text;
   struct editable_file * file;
   struct file_line * cur_line;
   unsigned line_number;
   char target[1024];
   jb_err err;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "s", &sectionid);
   if (err)
   {
      return err;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   line_number = 1;
   cur_line = file->lines;

   if (sectionid <= 1U)
   {
      /* Add to start of file */
      if (cur_line != NULL && cur_line->type != FILE_LINE_ACTION)
      {
         /* There's something in the file, find the line before the first
          * action.
          */
         while ((cur_line->next != NULL)
              && (cur_line->next->type != FILE_LINE_ACTION))
         {
            cur_line = cur_line->next;
            line_number++;
         }
      }
      else
      {
         /* File starts with action line, so insert at top */
         cur_line = NULL;
      }
   }
   else
   {
      /* Add after stated section. */
      while ((cur_line != NULL) && (line_number < sectionid))
      {
         cur_line = cur_line->next;
         line_number++;
      }

      if ((cur_line == NULL)
       || (cur_line->type != FILE_LINE_ACTION))
      {
         /* Invalid "sectionid" parameter */
         edit_free_file(file);
         return JB_ERR_CGI_PARAMS;
      }

      /* Skip through the section to find the last line in it. */
      while ((cur_line->next != NULL)
          && (cur_line->next->type != FILE_LINE_ACTION))
      {
         cur_line = cur_line->next;
         line_number++;
      }
   }

   /* At this point, the last line in the previous section is in cur_line
    * - add after this.  (Or if we need to add as the first line, cur_line
    * will be NULL).
    */

   new_text = strdup("{}");
   if (NULL == new_text)
   {
      edit_free_file(file);
      return JB_ERR_MEMORY;
   }

   /* Allocate the new line */
   new_line = zalloc_or_die(sizeof(*new_line));

   /* Fill in the data members of the new line */
   new_line->raw = NULL;
   new_line->prefix = NULL;
   new_line->unprocessed = new_text;
   new_line->type = FILE_LINE_ACTION;

   if (cur_line != NULL)
   {
      /* Link new_line into the list, after cur_line */
      new_line->next = cur_line->next;
      cur_line->next = new_line;
   }
   else
   {
      /* Link new_line into the list, as first line */
      new_line->next = file->lines;
      file->lines = new_line;
   }

   /* Done making changes, now commit */

   err = edit_write_file(file);
   if (err)
   {
      /* Error writing file */
      if (err == JB_ERR_FILE)
      {
         /* Read-only file. */
         err = cgi_error_file_read_only(csp, rsp, file->filename);
      }
      edit_free_file(file);
      return err;
   }

   snprintf(target, sizeof(target), CGI_PREFIX "edit-actions-list?foo=%lu&f=%u",
            (long) time(NULL), file->identifier);

   edit_free_file(file);

   return cgi_redirect(rsp, target);
}


/*********************************************************************
 *
 * Function    :  cgi_edit_actions_section_swap
 *
 * Description :  CGI function that swaps the order of two sections
 *                in the actions file.  Note that this CGI can actually
 *                swap any two arbitrary sections, but the GUI interface
 *                currently only allows consecutive sections to be
 *                specified.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *           f : (filename) Identifies the file to edit
 *           v : (version) File's last-modified time
 *          s1 : (section1) Line number of first section to swap
 *          s2 : (section2) Line number of second section to swap
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *                JB_ERR_CGI_PARAMS if the CGI parameters are not
 *                                  specified or not valid.
 *
 *********************************************************************/
jb_err cgi_edit_actions_section_swap(struct client_state *csp,
                                     struct http_response *rsp,
                                     const struct map *parameters)
{
   unsigned section1;
   unsigned section2;
   struct editable_file * file;
   struct file_line * cur_line;
   struct file_line * prev_line;
   struct file_line * line_before_section1;
   struct file_line * line_start_section1;
   struct file_line * line_end_section1;
   struct file_line * line_after_section1;
   struct file_line * line_before_section2;
   struct file_line * line_start_section2;
   struct file_line * line_end_section2;
   struct file_line * line_after_section2;
   unsigned line_number;
   char target[1024];
   jb_err err;

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_EDIT_ACTIONS))
   {
      return cgi_error_disabled(csp, rsp);
   }

   err = get_number_param(csp, parameters, "s1", &section1);
   if (!err) err = get_number_param(csp, parameters, "s2", &section2);
   if (err)
   {
      return err;
   }

   if (section1 > section2)
   {
      unsigned temp = section2;
      section2 = section1;
      section1 = temp;
   }

   err = edit_read_actions_file(csp, rsp, parameters, 1, &file);
   if (err)
   {
      /* No filename specified, can't read file, modified, or out of memory. */
      return (err == JB_ERR_FILE ? JB_ERR_OK : err);
   }

   /* Start at the beginning... */
   line_number = 1;
   cur_line = file->lines;
   prev_line = NULL;

   /* ... find section1 ... */
   while ((cur_line != NULL) && (line_number < section1))
   {
      prev_line = cur_line;
      cur_line = cur_line->next;
      line_number++;
   }

   if ((cur_line == NULL)
    || (cur_line->type != FILE_LINE_ACTION))
   {
      /* Invalid "section1" parameter */
      edit_free_file(file);
      return JB_ERR_CGI_PARAMS;
   }

   /* If no-op, we've validated params and can skip the rest. */
   if (section1 != section2)
   {
      /* ... find the end of section1 ... */
      line_before_section1 = prev_line;
      line_start_section1 = cur_line;
      do
      {
         prev_line = cur_line;
         cur_line = cur_line->next;
         line_number++;
      }
      while ((cur_line != NULL) && (cur_line->type == FILE_LINE_URL));
      line_end_section1 = prev_line;
      line_after_section1 = cur_line;

      /* ... find section2 ... */
      while ((cur_line != NULL) && (line_number < section2))
      {
         prev_line = cur_line;
         cur_line = cur_line->next;
         line_number++;
      }

      if ((cur_line == NULL)
       || (cur_line->type != FILE_LINE_ACTION))
      {
         /* Invalid "section2" parameter */
         edit_free_file(file);
         return JB_ERR_CGI_PARAMS;
      }

      /* ... find the end of section2 ... */
      line_before_section2 = prev_line;
      line_start_section2 = cur_line;
      do
      {
         prev_line = cur_line;
         cur_line = cur_line->next;
         line_number++;
      }
      while ((cur_line != NULL) && (cur_line->type == FILE_LINE_URL));
      line_end_section2 = prev_line;
      line_after_section2 = cur_line;

      /* Now have all the pointers we need. Do the swap. */

      /* Change the pointer to section1 to point to section2 instead */
      if (line_before_section1 == NULL)
      {
         file->lines = line_start_section2;
      }
      else
      {
         line_before_section1->next = line_start_section2;
      }

      if (line_before_section2 == line_end_section1)
      {
         /* Consecutive sections */
         line_end_section2->next = line_start_section1;
      }
      else
      {
         line_end_section2->next = line_after_section1;
         line_before_section2->next = line_start_section1;
      }

      /* Set the pointer from the end of section1 to the rest of the file */
      line_end_section1->next = line_after_section2;

      err = edit_write_file(file);
      if (err)
      {
         /* Error writing file */
         if (err == JB_ERR_FILE)
         {
            /* Read-only file. */
            err = cgi_error_file_read_only(csp, rsp, file->filename);
         }
         edit_free_file(file);
         return err;
      }
   } /* END if (section1 != section2) */

   snprintf(target, sizeof(target), CGI_PREFIX "edit-actions-list?foo=%lu&f=%u",
            (long) time(NULL), file->identifier);

   edit_free_file(file);

   return cgi_redirect(rsp, target);
}


/*********************************************************************
 *
 * Function    :  javascriptify
 *
 * Description :  Converts a string into a form JavaScript will like.
 *
 *                Netscape 4's JavaScript sucks - it doesn't use
 *                "id" parameters, so you have to set the "name"
 *                used to submit a form element to something JavaScript
 *                will like.  (Or access the elements by index in an
 *                array.  That array contains >60 elements and will
 *                be changed whenever we add a new action to the
 *                editor, so I'm NOT going to use indexes that have
 *                to be figured out by hand.)
 *
 *                Currently the only thing we have to worry about
 *                is "-" ==> "_" conversion.
 *
 *                This is a length-preserving operation so it is
 *                carried out in-place, no memory is allocated
 *                or freed.
 *
 * Parameters  :
 *          1  :  identifier = String to make JavaScript-friendly.
 *
 * Returns     :  N/A
 *
 *********************************************************************/
static void javascriptify(char * identifier)
{
   char * p = identifier;
   while (NULL != (p = strchr(p, '-')))
   {
      *p++ = '_';
   }
}


/*********************************************************************
 *
 * Function    :  actions_to_radio
 *
 * Description :  Converts a actionsfile entry into settings for
 *                radio buttons and edit boxes on a HTML form.
 *
 * Parameters  :
 *          1  :  exports = List of substitutions to add to.
 *          2  :  action  = Action to read
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *
 *********************************************************************/
static jb_err actions_to_radio(struct map * exports,
                               const struct action_spec *action)
{
   unsigned long mask;
   unsigned long add;
   int mapped_param;
   int checked;
   char current_mode;

   assert(exports);
   assert(action);

   mask = action->mask;
   add  = action->add;

   /* sanity - prevents "-feature +feature" */
   mask |= add;


#define DEFINE_ACTION_BOOL(name, bit)                 \
   if (!(mask & bit))                                 \
   {                                                  \
      current_mode = 'n';                             \
   }                                                  \
   else if (add & bit)                                \
   {                                                  \
      current_mode = 'y';                             \
   }                                                  \
   else                                               \
   {                                                  \
      current_mode = 'x';                             \
   }                                                  \
   if (map_radio(exports, name, "ynx", current_mode)) \
   {                                                  \
      return JB_ERR_MEMORY;                           \
   }

#define DEFINE_ACTION_STRING(name, bit, index)        \
   DEFINE_ACTION_BOOL(name, bit);                     \
   mapped_param = 0;

#define DEFINE_CGI_PARAM_RADIO(name, bit, index, value, is_default)  \
   if (add & bit)                                                    \
   {                                                                 \
      checked = !strcmp(action->string[index], value);               \
   }                                                                 \
   else                                                              \
   {                                                                 \
      checked = is_default;                                          \
   }                                                                 \
   mapped_param |= checked;                                          \
   if (map(exports, name "-param-" value, 1, (checked ? "checked" : ""), 1)) \
   {                                                                 \
      return JB_ERR_MEMORY;                                          \
   }

#define DEFINE_CGI_PARAM_CUSTOM(name, bit, index, default_val)       \
   if (map(exports, name "-param-custom", 1,                         \
           ((!mapped_param) ? "checked" : ""), 1))                   \
   {                                                                 \
      return JB_ERR_MEMORY;                                          \
   }                                                                 \
   if (map(exports, name "-param", 1,                                \
           (((add & bit) && !mapped_param) ?                         \
           action->string[index] : default_val), 1))                 \
   {                                                                 \
      return JB_ERR_MEMORY;                                          \
   }

#define DEFINE_CGI_PARAM_NO_RADIO(name, bit, index, default_val)     \
   if (map(exports, name "-param", 1,                                \
           ((add & bit) ? action->string[index] : default_val), 1))  \
   {                                                                 \
      return JB_ERR_MEMORY;                                          \
   }

#define DEFINE_ACTION_MULTI(name, index)              \
   if (action->multi_add[index]->first)               \
   {                                                  \
      current_mode = 'y';                             \
   }                                                  \
   else if (action->multi_remove_all[index])          \
   {                                                  \
      current_mode = 'n';                             \
   }                                                  \
   else if (action->multi_remove[index]->first)       \
   {                                                  \
      current_mode = 'y';                             \
   }                                                  \
   else                                               \
   {                                                  \
      current_mode = 'x';                             \
   }                                                  \
   if (map_radio(exports, name, "ynx", current_mode)) \
   {                                                  \
      return JB_ERR_MEMORY;                           \
   }

#define DEFINE_ACTION_ALIAS 0 /* No aliases for output */

#include "actionlist.h"

#undef DEFINE_ACTION_MULTI
#undef DEFINE_ACTION_STRING
#undef DEFINE_ACTION_BOOL
#undef DEFINE_ACTION_ALIAS
#undef DEFINE_CGI_PARAM_CUSTOM
#undef DEFINE_CGI_PARAM_RADIO
#undef DEFINE_CGI_PARAM_NO_RADIO

   return JB_ERR_OK;
}


/*********************************************************************
 *
 * Function    :  actions_from_radio
 *
 * Description :  Converts a map of parameters passed to a CGI function
 *                into an actionsfile entry.
 *
 * Parameters  :
 *          1  :  parameters = parameters to the CGI call
 *          2  :  action  = Action to change.  Must be valid before
 *                          the call, actions not specified will be
 *                          left unchanged.
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *
 *********************************************************************/
static jb_err actions_from_radio(const struct map * parameters,
                                 struct action_spec *action)
{
   const char * param;
   char * param_dup;
   char ch;
   const char * js_name;
   jb_err err = JB_ERR_OK;

   assert(parameters);
   assert(action);

   /* Statics are generally a potential race condition,
    * but in this case we're safe and don't need semaphores.
    * Be careful if you modify this function.
    * - Jon
    * The js_name_arr's are never free()d, but this is no
    * problem, since they will only be created once and
    * used by all threads thereafter. -oes
    */

#define JAVASCRIPTIFY(dest_var, string)               \
   {                                                  \
     static int first_time = 1;                       \
     static char *js_name_arr;                        \
      if (first_time)                                 \
      {                                               \
         js_name_arr = strdup(string);                \
         javascriptify(js_name_arr);                  \
      }                                               \
      dest_var = js_name_arr;                         \
      first_time = 0;                                 \
   }                                                  \

#define DEFINE_ACTION_BOOL(name, bit)                 \
   JAVASCRIPTIFY(js_name, name);                      \
   ch = get_char_param(parameters, js_name);          \
   if (ch == 'Y')                                     \
   {                                                  \
      action->add  |= bit;                            \
      action->mask |= bit;                            \
   }                                                  \
   else if (ch == 'N')                                \
   {                                                  \
      action->add  &= ~bit;                           \
      action->mask &= ~bit;                           \
   }                                                  \
   else if (ch == 'X')                                \
   {                                                  \
      action->add  &= ~bit;                           \
      action->mask |= bit;                            \
   }                                                  \

#define DEFINE_ACTION_STRING(name, bit, index)                 \
   JAVASCRIPTIFY(js_name, name);                               \
   ch = get_char_param(parameters, js_name);                   \
   if (ch == 'Y')                                              \
   {                                                           \
      param = NULL;                                            \
      JAVASCRIPTIFY(js_name, name "-mode");                    \
      if (!err) err = get_string_param(parameters, js_name, &param);    \
      if ((param == NULL) || (0 == strcmp(param, "CUSTOM")))            \
      {                                                                 \
         JAVASCRIPTIFY(js_name, name "-param");                         \
         if (!err) err = get_string_param(parameters, js_name, &param); \
      }                                                        \
      if (param != NULL)                                       \
      {                                                        \
         if (NULL == (param_dup = strdup(param)))              \
         {                                                     \
            return JB_ERR_MEMORY;                              \
         }                                                     \
         freez(action->string[index]);                         \
         action->add  |= bit;                                  \
         action->mask |= bit;                                  \
         action->string[index] = param_dup;                    \
      }                                                        \
   }                                                           \
   else if (ch == 'N')                                         \
   {                                                           \
      if (action->add & bit)                                   \
      {                                                        \
         freez(action->string[index]);                         \
      }                                                        \
      action->add  &= ~bit;                                    \
      action->mask &= ~bit;                                    \
   }                                                           \
   else if (ch == 'X')                                         \
   {                                                           \
      if (action->add & bit)                                   \
      {                                                        \
         freez(action->string[index]);                         \
      }                                                        \
      action->add  &= ~bit;                                    \
      action->mask |= bit;                                     \
   }                                                           \

#define DEFINE_ACTION_MULTI(name, index)                       \
   JAVASCRIPTIFY(js_name, name);                               \
   ch = get_char_param(parameters, js_name);                   \
   if (ch == 'Y')                                              \
   {                                                           \
      /* FIXME */                                              \
   }                                                           \
   else if (ch == 'N')                                         \
   {                                                           \
      list_remove_all(action->multi_add[index]);               \
      list_remove_all(action->multi_remove[index]);            \
      action->multi_remove_all[index] = 1;                     \
   }                                                           \
   else if (ch == 'X')                                         \
   {                                                           \
      list_remove_all(action->multi_add[index]);               \
      list_remove_all(action->multi_remove[index]);            \
      action->multi_remove_all[index] = 0;                     \
   }                                                           \

#define DEFINE_ACTION_ALIAS 0 /* No aliases for URL parsing */

#include "actionlist.h"

#undef DEFINE_ACTION_MULTI
#undef DEFINE_ACTION_STRING
#undef DEFINE_ACTION_BOOL
#undef DEFINE_ACTION_ALIAS
#undef JAVASCRIPTIFY

   return err;
}
#endif /* def FEATURE_CGI_EDIT_ACTIONS */


#ifdef FEATURE_TOGGLE
/*********************************************************************
 *
 * Function    :  cgi_toggle
 *
 * Description :  CGI function that adds a new empty section to
 *                an actions file.
 *
 * Parameters  :
 *          1  :  csp = Current client state (buffers, headers, etc...)
 *          2  :  rsp = http_response data structure for output
 *          3  :  parameters = map of cgi parameters
 *
 * CGI Parameters :
 *         set : If present, how to change toggle setting:
 *               "enable", "disable", "toggle", or none (default).
 *        mini : If present, use mini reply template.
 *
 * Returns     :  JB_ERR_OK     on success
 *                JB_ERR_MEMORY on out-of-memory
 *
 *********************************************************************/
jb_err cgi_toggle(struct client_state *csp,
                  struct http_response *rsp,
                  const struct map *parameters)
{
   struct map *exports;
   char mode;
   const char *template_name;

   assert(csp);
   assert(rsp);
   assert(parameters);

   if (0 == (csp->config->feature_flags & RUNTIME_FEATURE_CGI_TOGGLE))
   {
      return cgi_error_disabled(csp, rsp);
   }

   mode = get_char_param(parameters, "set");

   if (mode == 'E')
   {
      /* Enable */
      global_toggle_state = 1;
   }
   else if (mode == 'D')
   {
      /* Disable */
      global_toggle_state = 0;
   }
   else if (mode == 'T')
   {
      /* Toggle */
      global_toggle_state = !global_toggle_state;
   }

   log_error(LOG_LEVEL_INFO, "Now toggled %s.", global_toggle_state ? "ON" : "OFF");

   if (NULL == (exports = default_exports(csp, "toggle")))
   {
      return JB_ERR_MEMORY;
   }

   template_name = (get_char_param(parameters, "mini")
                 ? "toggle-mini"
                 : "toggle");

   return template_fill_for_cgi(csp, template_name, exports, rsp);
}
#endif /* def FEATURE_TOGGLE */


/*
  Local Variables:
  tab-width: 3
  end:
*/