-const char pcrs_rcs[] = "$Id: pcrs.c,v 1.11 2001/08/15 15:26:24 oes Exp $";
-
+const char pcrs_rcs[] = "$Id: pcrs.c,v 1.28 2007/08/18 14:37:27 fabiankeil Exp $";
/*********************************************************************
*
* File : $Source: /cvsroot/ijbswa/current/pcrs.c,v $
*
- * Purpose : pcrs is a supplement to the brilliant pcre library by Philip
- * Hazel <ph10@cam.ac.uk> and adds Perl-style substitution. That
- * is, it mimics Perl's 's' operator.
- *
- * Currently, there's no documentation besides comments and the
- * source itself :-(
+ * Purpose : pcrs is a supplement to the pcre library by Philip Hazel
+ * <ph10@cam.ac.uk> and adds Perl-style substitution. That
+ * is, it mimics Perl's 's' operator. See pcrs(3) for details.
*
- * Note: In addition to perl's options, 'U' for ungreedy and 'T'
- * for trivial (i.e.: ignore backrefs in the substitute) are
- * supported.
+ * WARNING: This file contains additional functions and bug
+ * fixes that aren't part of the latest official pcrs package
+ * (which apparently is no longer maintained).
*
* Copyright : Written and Copyright (C) 2000, 2001 by Andreas S. Oesterhelt
* <andreas@oesterhelt.org>
*
+ * Copyright (C) 2006, 2007 Fabian Keil <fk@fabiankeil.de>
+ *
* 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.
+ * and/or modify it under the terms of the GNU Lesser
+ * General Public License (LGPL), version 2.1, which should
+ * be included in this distribution (see LICENSE.txt), with
+ * the exception that the permission to replace that license
+ * with the GNU General Public License (GPL) given in section
+ * 3 is restricted to version 2 of the GPL.
*
* 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.
+ * PARTICULAR PURPOSE. See the 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
+ * The GNU Lesser General Public License should be included
+ * with this file. If not, you can view it at
+ * http://www.gnu.org/licenses/lgpl.html
* or write to the Free Software Foundation, Inc., 59
* Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Revisions :
* $Log: pcrs.c,v $
+ * Revision 1.28 2007/08/18 14:37:27 fabiankeil
+ * Ditch hex_to_byte() in favour of xtoi().
+ *
+ * Revision 1.27 2007/08/05 13:47:04 fabiankeil
+ * #1763173 from Stefan Huehner: s@const static@static const@.
+ *
+ * Revision 1.26 2007/07/01 13:29:54 fabiankeil
+ * Add limited hex notation support for the PCRS
+ * substitution text ('\x7e' = '~'). Closes #1627140.
+ *
+ * Revision 1.25 2007/04/30 15:02:18 fabiankeil
+ * Introduce dynamic pcrs jobs that can resolve variables.
+ *
+ * Revision 1.24 2007/01/05 15:46:12 fabiankeil
+ * Don't use strlen() to calculate the length of
+ * the pcrs substitutes. They don't have to be valid C
+ * strings and getting their length wrong can result in
+ * user-controlled memory corruption.
+ *
+ * Thanks to Felix Gröbert for reporting the problem
+ * and providing the fix [#1627140].
+ *
+ * Revision 1.23 2006/12/29 17:53:05 fabiankeil
+ * Fixed gcc43 conversion warnings.
+ *
+ * Revision 1.22 2006/12/24 17:34:20 fabiankeil
+ * Add pcrs_strerror() message for PCRE_ERROR_MATCHLIMIT
+ * and give a hint why an error code might be unknown.
+ *
+ * Catch NULL subjects early in pcrs_execute().
+ *
+ * Revision 1.21 2006/07/18 14:48:47 david__schmidt
+ * Reorganizing the repository: swapping out what was HEAD (the old 3.1 branch)
+ * with what was really the latest development (the v_3_0_branch branch)
+ *
+ * Revision 1.19.2.4 2005/05/07 21:50:55 david__schmidt
+ * A few memory leaks plugged (mostly on error paths)
+ *
+ * Revision 1.19.2.3 2003/12/04 12:32:45 oes
+ * Append a trailing nullbyte to result to facilitate string processing
+ *
+ * Revision 1.19.2.2 2002/10/08 16:22:28 oes
+ * Bugfix: Need to check validity of backreferences explicitly,
+ * because when max_matches are reached and matches is expanded,
+ * realloc() does not zero the memory. Fixes Bug # 606227
+ *
+ * Revision 1.19.2.1 2002/08/10 11:23:40 oes
+ * Include prce.h via project.h, where the appropriate
+ * source will have been selected
+ *
+ * Revision 1.19 2002/03/08 14:47:48 oes
+ * Cosmetics
+ *
+ * Revision 1.18 2002/03/08 14:17:14 oes
+ * Fixing -Wconversion warnings
+ *
+ * Revision 1.17 2002/03/08 13:45:48 oes
+ * Hiding internal functions
+ *
+ * Revision 1.16 2001/11/30 21:32:14 jongfoster
+ * Fixing signed/unsigned comparison (Andreas please check this!)
+ * One tab->space
+ *
+ * Revision 1.15 2001/09/20 16:11:06 steudten
+ *
+ * Add casting for some string functions.
+ *
+ * Revision 1.14 2001/09/09 21:41:57 oes
+ * Fixing yet another silly bug
+ *
+ * Revision 1.13 2001/09/06 14:05:59 oes
+ * Fixed silly bug
+ *
+ * Revision 1.12 2001/08/18 11:35:00 oes
+ * - Introduced pcrs_strerror()
+ * - made some NULL arguments non-fatal
+ * - added support for \n \r \e \b \t \f \a \0 in substitute
+ * - made quoting adhere to standard rules
+ * - added warning for bad backrefs
+ * - added pcrs_execute_list()
+ * - fixed comments
+ * - bugfix & cosmetics
+ *
+ * Revision 1.11 2001/08/15 15:32:03 oes
+ * - Added support for Perl's special variables $+, $' and $`
+ * - Improved the substitute parser
+ * - Replaced the hard limit for the maximum number of matches
+ * by dynamic reallocation
+ *
* Revision 1.10 2001/08/05 13:13:11 jongfoster
* Making parameters "const" where possible.
*
*********************************************************************/
\f
-#include <pcre.h>
#include <string.h>
+#include <ctype.h>
+#include <assert.h>
+
+/*
+ * Include project.h just so that the right pcre.h gets
+ * included from there
+ */
+#include "project.h"
+
+/* For snprintf only */
+#include "miscutil.h"
+/* For xtoi */
+#include "encode.h"
+
#include "pcrs.h"
-#include <stdio.h>
+
const char pcrs_h_rcs[] = PCRS_H_VERSION;
+/*
+ * Internal prototypes
+ */
+
+static int pcrs_parse_perl_options(const char *optstring, int *flags);
+static pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialflag,
+ int capturecount, int *errptr);
+static int is_hex_sequence(const char *sequence);
+
+/*********************************************************************
+ *
+ * Function : pcrs_strerror
+ *
+ * Description : Return a string describing a given error code.
+ *
+ * Parameters :
+ * 1 : error = the error code
+ *
+ * Returns : char * to the descriptive string
+ *
+ *********************************************************************/
+const char *pcrs_strerror(const int error)
+{
+ if (error < 0)
+ {
+ switch (error)
+ {
+ /* Passed-through PCRE error: */
+ case PCRE_ERROR_NOMEMORY: return "(pcre:) No memory";
+
+ /* Shouldn't happen unless PCRE or PCRS bug, or user messed with compiled job: */
+ case PCRE_ERROR_NULL: return "(pcre:) NULL code or subject or ovector";
+ case PCRE_ERROR_BADOPTION: return "(pcre:) Unrecognized option bit";
+ case PCRE_ERROR_BADMAGIC: return "(pcre:) Bad magic number in code";
+ case PCRE_ERROR_UNKNOWN_NODE: return "(pcre:) Bad node in pattern";
+
+ /* Can't happen / not passed: */
+ case PCRE_ERROR_NOSUBSTRING: return "(pcre:) Fire in power supply";
+ case PCRE_ERROR_NOMATCH: return "(pcre:) Water in power supply";
+
+#ifdef PCRE_ERROR_MATCHLIMIT
+ /*
+ * Only reported by PCRE versions newer than our own.
+ */
+ case PCRE_ERROR_MATCHLIMIT: return "(pcre:) Match limit reached";
+#endif /* def PCRE_ERROR_MATCHLIMIT */
+
+ /* PCRS errors: */
+ case PCRS_ERR_NOMEM: return "(pcrs:) No memory";
+ case PCRS_ERR_CMDSYNTAX: return "(pcrs:) Syntax error while parsing command";
+ case PCRS_ERR_STUDY: return "(pcrs:) PCRE error while studying the pattern";
+ case PCRS_ERR_BADJOB: return "(pcrs:) Bad job - NULL job, pattern or substitute";
+ case PCRS_WARN_BADREF: return "(pcrs:) Backreference out of range";
+ case PCRS_WARN_TRUNCATION:
+ return "(pcrs:) At least one variable was too big and has been truncated before compilation";
+
+ /*
+ * XXX: With the exception of PCRE_ERROR_MATCHLIMIT we
+ * only catch PCRE errors that can happen with our internal
+ * version. If Privoxy is linked against a newer
+ * PCRE version all bets are off ...
+ */
+ default: return "Unknown error. Privoxy out of sync with PCRE?";
+ }
+ }
+ /* error >= 0: No error */
+ return "(pcrs:) Everything's just fine. Thanks for asking.";
+
+}
+
/*********************************************************************
*
* Returns : option integer suitable for pcre
*
*********************************************************************/
-int pcrs_parse_perl_options(const char *optstring, int *flags)
+static int pcrs_parse_perl_options(const char *optstring, int *flags)
{
size_t i;
int rc = 0;
*flags = 0;
- for (i=0; i < strlen(optstring); i++)
+
+ if (NULL == optstring) return 0;
+
+ for (i = 0; i < strlen(optstring); i++)
{
switch(optstring[i])
{
case 's': rc |= PCRE_DOTALL; break;
case 'x': rc |= PCRE_EXTENDED; break;
case 'U': rc |= PCRE_UNGREEDY; break;
- case 'T': *flags |= PCRS_TRIVIAL; break;
- default: break;
+ case 'T': *flags |= PCRS_TRIVIAL; break;
+ default: break;
}
}
return rc;
* the reason.
*
*********************************************************************/
-pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialflag, int capturecount, int *errptr)
+static pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialflag, int capturecount, int *errptr)
{
- int length, i, k, l, quoted;
+ int i, k, l, quoted;
+ size_t length;
char *text;
pcrs_substitute *r;
i = k = l = quoted = 0;
+ /*
+ * Sanity check
+ */
+ if (NULL == replacement)
+ {
+ replacement = "";
+ }
+
/*
* Get memory or fail
*/
*errptr = PCRS_ERR_NOMEM;
return NULL;
}
- memset(r, '\0', length + 1);
+ memset(text, '\0', length + 1);
/*
if (trivialflag)
{
text = strncpy(text, replacement, length + 1);
- k = length;
+ k = (int)length;
}
/*
*/
else
{
- while(i < length)
+ while (i < (int)length)
{
/* Quoting */
if (replacement[i] == '\\')
}
else
{
- quoted = 1;
- i++;
+ if (replacement[i+1] && strchr("tnrfae0", replacement[i+1]))
+ {
+ switch (replacement[++i])
+ {
+ case 't':
+ text[k++] = '\t';
+ break;
+ case 'n':
+ text[k++] = '\n';
+ break;
+ case 'r':
+ text[k++] = '\r';
+ break;
+ case 'f':
+ text[k++] = '\f';
+ break;
+ case 'a':
+ text[k++] = 7;
+ break;
+ case 'e':
+ text[k++] = 27;
+ break;
+ case '0':
+ text[k++] = '\0';
+ break;
+ }
+ i++;
+ }
+ else if (is_hex_sequence(&replacement[i]))
+ {
+ /*
+ * Replace a hex sequence with a single
+ * character with the sequence's ascii value.
+ * e.g.: '\x7e' => '~'
+ */
+ const int ascii_value = xtoi(&replacement[i+2]);
+
+ assert(ascii_value > 0);
+ assert(ascii_value < 256);
+ text[k++] = (char)ascii_value;
+ i += 4;
+ }
+ else
+ {
+ quoted = 1;
+ i++;
+ }
}
continue;
}
/* Backreferences */
- if (replacement[i] == '$' && !quoted && i < length - 1)
+ if (replacement[i] == '$' && !quoted && i < (int)(length - 1))
{
char *symbol, symbols[] = "'`+&";
- r->block_length[l] = k - r->block_offset[l];
+ r->block_length[l] = (size_t)(k - r->block_offset[l]);
/* Numerical backreferences */
- if (isdigit(replacement[i + 1]))
+ if (isdigit((int)replacement[i + 1]))
{
- while (i < length && isdigit(replacement[++i]))
+ while (i < (int)length && isdigit((int)replacement[++i]))
{
r->backref[l] = r->backref[l] * 10 + replacement[i] - 48;
}
+ if (r->backref[l] > capturecount)
+ {
+ *errptr = PCRS_WARN_BADREF;
+ }
}
/* Symbolic backreferences: */
r->backref_count[r->backref[l]] += 1;
r->block_offset[++l] = k;
}
+ else
+ {
+ *errptr = PCRS_WARN_BADREF;
+ }
continue;
}
*/
r->text = text;
r->backrefs = l;
- r->block_length[l] = k - r->block_offset[l];
+ r->length = (size_t)k;
+ r->block_length[l] = (size_t)(k - r->block_offset[l]);
return r;
*********************************************************************/
pcrs_job *pcrs_compile_command(const char *command, int *errptr)
{
- int i, k, l, limit, quoted = FALSE;
+ int i, k, l, quoted = FALSE;
+ size_t limit;
char delimiter;
char *tokens[4];
pcrs_job *newjob;
-
+
i = k = l = 0;
-
+
/*
* Tokenize the perl command
*/
}
else
{
- delimiter = command[1];
+ delimiter = command[1];
}
tokens[l] = (char *) malloc(limit + 1);
- for (i=0; i <= limit; i++)
+ for (i = 0; i <= (int)limit; i++)
{
-
+
if (command[i] == delimiter && !quoted)
{
- if (l == 3)
- {
- l = -1;
+ if (l == 3)
+ {
+ l = -1;
break;
}
tokens[0][k++] = '\0';
tokens[++l] = tokens[0] + k;
continue;
}
-
- else if (command[i] == '\\' && !quoted && i+1 < limit && command[i+1] == delimiter)
+
+ else if (command[i] == '\\' && !quoted)
{
quoted = TRUE;
- continue;
+ if (command[i+1] == delimiter) continue;
+ }
+ else
+ {
+ quoted = FALSE;
}
tokens[0][k++] = command[i];
- quoted = FALSE;
}
/*
free(tokens[0]);
return NULL;
}
-
+
newjob = pcrs_compile(tokens[1], tokens[2], tokens[3], errptr);
free(tokens[0]);
return newjob;
-
+
}
int capturecount;
const char *error;
+ *errptr = 0;
/*
* Handle NULL arguments
*/
if (pattern == NULL) pattern = "";
if (substitute == NULL) substitute = "";
- if (options == NULL) options = "";
/*
}
+/*********************************************************************
+ *
+ * Function : pcrs_execute_list
+ *
+ * Description : This is a multiple job wrapper for pcrs_execute().
+ * Apply the regular substitutions defined by the jobs in
+ * the joblist to the subject.
+ * The subject itself is left untouched, memory for the result
+ * is malloc()ed and it is the caller's responsibility to free
+ * the result when it's no longer needed.
+ *
+ * Note: For convenient string handling, a null byte is
+ * appended to the result. It does not count towards the
+ * result_length, though.
+ *
+ *
+ * Parameters :
+ * 1 : joblist = the chained list of pcrs_jobs to be executed
+ * 2 : subject = the subject string
+ * 3 : subject_length = the subject's length
+ * 4 : result = char** for returning the result
+ * 5 : result_length = size_t* for returning the result's length
+ *
+ * Returns : On success, the number of substitutions that were made.
+ * May be > 1 if job->flags contained PCRS_GLOBAL
+ * On failure, the (negative) pcre error code describing the
+ * failure, which may be translated to text using pcrs_strerror().
+ *
+ *********************************************************************/
+int pcrs_execute_list(pcrs_job *joblist, char *subject, size_t subject_length, char **result, size_t *result_length)
+{
+ pcrs_job *job;
+ char *old, *new = NULL;
+ int hits, total_hits;
+
+ old = subject;
+ *result_length = subject_length;
+ hits = total_hits = 0;
+
+ for (job = joblist; job != NULL; job = job->next)
+ {
+ hits = pcrs_execute(job, old, *result_length, &new, result_length);
+
+ if (old != subject) free(old);
+
+ if (hits < 0)
+ {
+ return(hits);
+ }
+ else
+ {
+ total_hits += hits;
+ old = new;
+ }
+ }
+
+ *result = new;
+ return(total_hits);
+
+}
+
+
/*********************************************************************
*
* Function : pcrs_execute
*
- * Description : Modify the subject by executing the regular substitution
- * defined by the job. Since the result may be longer than
- * the subject, its space requirements are precalculated in
- * the matching phase and new memory is allocated accordingly.
- * It is the caller's responsibility to free the result when
- * it's no longer needed.
+ * Description : Apply the regular substitution defined by the job to the
+ * subject.
+ * The subject itself is left untouched, memory for the result
+ * is malloc()ed and it is the caller's responsibility to free
+ * the result when it's no longer needed.
+ *
+ * Note: For convenient string handling, a null byte is
+ * appended to the result. It does not count towards the
+ * result_length, though.
*
* Parameters :
* 1 : job = the pcrs_job to be executed
* 2 : subject = the subject (== original) string
* 3 : subject_length = the subject's length
- * INCLUDING the terminating zero, if string!
* 4 : result = char** for returning the result
- * 5 : result_length = int* for returning the result's length
- * 6 : max_matches = maximum number of matches in global searches
+ * 5 : result_length = size_t* for returning the result's length
*
- * Returns : the number of substitutions that were made. May be > 1
- * if job->flags contained PCRS_GLOBAL
+ * Returns : On success, the number of substitutions that were made.
+ * May be > 1 if job->flags contained PCRS_GLOBAL
+ * On failure, the (negative) pcre error code describing the
+ * failure, which may be translated to text using pcrs_strerror().
*
*********************************************************************/
-int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result, int *result_length)
+int pcrs_execute(pcrs_job *job, const char *subject, size_t subject_length, char **result, size_t *result_length)
{
int offsets[3 * PCRS_MAX_SUBMATCHES],
- offset, i, k,
+ offset,
+ i, k,
matches_found,
- newsize,
submatches,
max_matches = PCRS_MAX_MATCH_INIT;
+ size_t newsize;
pcrs_match *matches, *dummy;
char *result_offset;
/*
* Sanity check & memory allocation
*/
- if (job == NULL || job->pattern == NULL || job->substitute == NULL)
+ if (job == NULL || job->pattern == NULL || job->substitute == NULL || NULL == subject)
{
*result = NULL;
return(PCRS_ERR_BADJOB);
}
- if (NULL == (matches = (pcrs_match *)malloc(max_matches * sizeof(pcrs_match))))
+ if (NULL == (matches = (pcrs_match *)malloc((size_t)max_matches * sizeof(pcrs_match))))
{
*result = NULL;
return(PCRS_ERR_NOMEM);
}
- memset(matches, '\0', max_matches * sizeof(pcrs_match));
+ memset(matches, '\0', (size_t)max_matches * sizeof(pcrs_match));
/*
* Find the pattern and calculate the space
* requirements for the result
*/
- newsize=subject_length;
+ newsize = subject_length;
- while ((submatches = pcre_exec(job->pattern, job->hints, subject, subject_length, offset, 0, offsets, 3 * PCRS_MAX_SUBMATCHES)) > 0)
+ while ((submatches = pcre_exec(job->pattern, job->hints, subject, (int)subject_length, offset, 0, offsets, 3 * PCRS_MAX_SUBMATCHES)) > 0)
{
job->flags |= PCRS_SUCCESS;
matches[i].submatches = submatches;
- for (k=0; k < submatches; k++)
+ for (k = 0; k < submatches; k++)
{
matches[i].submatch_offset[k] = offsets[2 * k];
/* Note: Non-found optional submatches have length -1-(-1)==0 */
- matches[i].submatch_length[k] = offsets[2 * k + 1] - offsets[2 * k];
+ matches[i].submatch_length[k] = (size_t)(offsets[2 * k + 1] - offsets[2 * k]);
/* reserve mem for each submatch as often as it is ref'd */
- newsize += matches[i].submatch_length[k] * job->substitute->backref_count[k];
+ newsize += matches[i].submatch_length[k] * (size_t)job->substitute->backref_count[k];
}
/* plus replacement text size minus match text size */
- newsize += strlen(job->substitute->text) - matches[i].submatch_length[0];
+ newsize += job->substitute->length - matches[i].submatch_length[0];
/* chunk before match */
matches[i].submatch_offset[PCRS_MAX_SUBMATCHES] = 0;
- matches[i].submatch_length[PCRS_MAX_SUBMATCHES] = offsets[0];
- newsize += offsets[0] * job->substitute->backref_count[PCRS_MAX_SUBMATCHES];
+ matches[i].submatch_length[PCRS_MAX_SUBMATCHES] = (size_t)offsets[0];
+ newsize += (size_t)offsets[0] * (size_t)job->substitute->backref_count[PCRS_MAX_SUBMATCHES];
/* chunk after match */
matches[i].submatch_offset[PCRS_MAX_SUBMATCHES + 1] = offsets[1];
- matches[i].submatch_length[PCRS_MAX_SUBMATCHES + 1] = subject_length - offsets[1] - 1;
- newsize += (subject_length - offsets[1])* job->substitute->backref_count[PCRS_MAX_SUBMATCHES + 1];
-
- /* Non-global search or limit reached? */
- if (!(job->flags & PCRS_GLOBAL)) break;
+ matches[i].submatch_length[PCRS_MAX_SUBMATCHES + 1] = subject_length - (size_t)offsets[1] - 1;
+ newsize += (subject_length - (size_t)offsets[1]) * (size_t)job->substitute->backref_count[PCRS_MAX_SUBMATCHES + 1];
/* Storage for matches exhausted? -> Extend! */
if (++i >= max_matches)
{
- max_matches *= PCRS_MAX_MATCH_GROW;
- if (NULL == (dummy = (pcrs_match *)realloc(matches, max_matches * sizeof(pcrs_match))))
+ max_matches = (int)(max_matches * PCRS_MAX_MATCH_GROW);
+ if (NULL == (dummy = (pcrs_match *)realloc(matches, (size_t)max_matches * sizeof(pcrs_match))))
{
free(matches);
*result = NULL;
matches = dummy;
}
+ /* Non-global search or limit reached? */
+ if (!(job->flags & PCRS_GLOBAL)) break;
+
/* Don't loop on empty matches */
if (offsets[1] == offset)
- if (offset < subject_length)
+ if ((size_t)offset < subject_length)
offset++;
else
break;
else
offset = offsets[1];
}
- /* Pass pcre error through if failiure */
- if (submatches < -1)
+ /* Pass pcre error through if (bad) failiure */
+ if (submatches < PCRE_ERROR_NOMATCH)
{
free(matches);
return submatches;
/*
- * Get memory for the result
+ * Get memory for the result (must be freed by caller!)
+ * and append terminating null byte.
*/
- if ((*result = (char *)malloc(newsize)) == NULL) /* must be free()d by caller */
+ if ((*result = (char *)malloc(newsize + 1)) == NULL)
{
free(matches);
return PCRS_ERR_NOMEM;
}
+ else
+ {
+ (*result)[newsize] = '\0';
+ }
/*
offset = 0;
result_offset = *result;
- for (i=0; i < matches_found; i++)
+ for (i = 0; i < matches_found; i++)
{
/* copy the chunk preceding the match */
- memcpy(result_offset, subject + offset, matches[i].submatch_offset[0] - offset);
+ memcpy(result_offset, subject + offset, (size_t)(matches[i].submatch_offset[0] - offset));
result_offset += matches[i].submatch_offset[0] - offset;
/* For every segment of the substitute.. */
- for (k=0; k <= job->substitute->backrefs; k++)
+ for (k = 0; k <= job->substitute->backrefs; k++)
{
/* ...copy its text.. */
memcpy(result_offset, job->substitute->text + job->substitute->block_offset[k], job->substitute->block_length[k]);
if (k != job->substitute->backrefs
/* ..in legal range.. */
&& job->substitute->backref[k] < PCRS_MAX_SUBMATCHES + 2
- /* ..and referencing a nonempty match.. */
+ /* ..and referencing a real submatch.. */
+ && job->substitute->backref[k] < matches[i].submatches
+ /* ..that is nonempty.. */
&& matches[i].submatch_length[job->substitute->backref[k]] > 0)
{
/* ..copy the submatch that is ref'd. */
result_offset += matches[i].submatch_length[job->substitute->backref[k]];
}
}
- offset = matches[i].submatch_offset[0] + matches[i].submatch_length[0];
+ offset = matches[i].submatch_offset[0] + (int)matches[i].submatch_length[0];
}
/* Copy the rest. */
- memcpy(result_offset, subject + offset, subject_length - offset);
+ memcpy(result_offset, subject + offset, subject_length - (size_t)offset);
*result_length = newsize;
free(matches);
}
+#define is_hex_digit(x) ((x) && strchr("0123456789ABCDEF", toupper(x)))
+
+/*********************************************************************
+ *
+ * Function : is_hex_sequence
+ *
+ * Description : Checks the first four characters of a string
+ * and decides if they are a valid hex sequence
+ * (like '\x40').
+ *
+ * Parameters :
+ * 1 : sequence = The string to check
+ *
+ * Returns : Non-zero if it's valid sequence, or
+ * Zero if it isn't.
+ *
+ *********************************************************************/
+static int is_hex_sequence(const char *sequence)
+{
+ return (sequence[0] == '\\' &&
+ sequence[1] == 'x' &&
+ is_hex_digit(sequence[2]) &&
+ is_hex_digit(sequence[3]));
+}
+
+
+/*
+ * Functions below this line are only part of the pcrs version
+ * included in Privoxy. If you use any of them you should not
+ * try to dynamically link against external pcrs versions.
+ */
+
+/*********************************************************************
+ *
+ * Function : pcrs_job_is_dynamic
+ *
+ * Description : Checks if a job has the "D" (dynamic) option set.
+ *
+ * Parameters :
+ * 1 : job = The job to check
+ *
+ * Returns : TRUE if the job is indeed dynamic, otherwise
+ * FALSE
+ *
+ *********************************************************************/
+int pcrs_job_is_dynamic (char *job)
+{
+ const char delimiter = job[1];
+ const size_t length = strlen(job);
+ char *option;
+
+ if (length < 5)
+ {
+ /*
+ * The shortest valid (but useless)
+ * dynamic pattern is "s@@@D"
+ */
+ return FALSE;
+ }
+
+ /*
+ * Everything between the last character
+ * and the last delimiter is an option ...
+ */
+ for (option = job + length; *option != delimiter; option--)
+ {
+ if (*option == 'D')
+ {
+ /*
+ * ... and if said option is 'D' the job is dynamic.
+ */
+ return TRUE;
+ }
+ }
+ return FALSE;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : pcrs_get_delimiter
+ *
+ * Description : Tries to find a character that is safe to
+ * be used as a pcrs delimiter for a certain string.
+ *
+ * Parameters :
+ * 1 : string = The string to search in
+ *
+ * Returns : A safe delimiter if one was found, otherwise '\0'.
+ *
+ *********************************************************************/
+char pcrs_get_delimiter(const char *string)
+{
+ /*
+ * Some characters that are unlikely to
+ * be part of pcrs replacement strings.
+ */
+ char delimiters[] = "><§#+*~%^°-:;µ!@";
+ char *d = delimiters;
+
+ /* Take the first delimiter that isn't part of the string */
+ while (*d && NULL != strchr(string, *d))
+ {
+ d++;
+ }
+ return *d;
+
+}
+
+
+/*********************************************************************
+ *
+ * Function : pcrs_execute_single_command
+ *
+ * Description : Apply single pcrs command to the subject.
+ * The subject itself is left untouched, memory for the result
+ * is malloc()ed and it is the caller's responsibility to free
+ * the result when it's no longer needed.
+ *
+ * Parameters :
+ * 1 : subject = the subject (== original) string
+ * 2 : pcrs_command = the pcrs command as string (s@foo@bar@)
+ * 3 : hits = int* for returning the number of modifications
+ *
+ * Returns : NULL in case of errors, otherwise the
+ * result of the pcrs command.
+ *
+ *********************************************************************/
+char *pcrs_execute_single_command(const char *subject, const char *pcrs_command, int *hits)
+{
+ size_t size;
+ char *result = NULL;
+ pcrs_job *job;
+
+ assert(subject);
+ assert(pcrs_command);
+
+ *hits = 0;
+ size = strlen(subject);
+
+ job = pcrs_compile_command(pcrs_command, hits);
+ if (NULL != job)
+ {
+ *hits = pcrs_execute(job, subject, size, &result, &size);
+ if (*hits < 0)
+ {
+ freez(result);
+ }
+ pcrs_free_job(job);
+ }
+ return result;
+
+}
+
+
+static const char warning[] = "... [too long, truncated]";
+/*********************************************************************
+ *
+ * Function : pcrs_compile_dynamic_command
+ *
+ * Description : Takes a dynamic pcrs command, fills in the
+ * values of the variables and compiles it.
+ *
+ * Parameters :
+ * 1 : csp = Current client state (buffers, headers, etc...)
+ * 2 : pcrs_command = The dynamic pcrs command to compile
+ * 3 : v = NULL terminated array of variables and their values.
+ * 4 : error = pcrs error code
+ *
+ * Returns : NULL in case of hard errors, otherwise the
+ * compiled pcrs job.
+ *
+ *********************************************************************/
+pcrs_job *pcrs_compile_dynamic_command(char *pcrs_command, const struct pcrs_variable v[], int *error)
+{
+ char buf[PCRS_BUFFER_SIZE];
+ const char *original_pcrs_command = pcrs_command;
+ char *pcrs_command_tmp = NULL;
+ pcrs_job *job = NULL;
+ int truncation = 0;
+ char d;
+ int ret;
+
+ while ((NULL != v->name) && (NULL != pcrs_command))
+ {
+ assert(NULL != v->value);
+
+ if (NULL == strstr(pcrs_command, v->name))
+ {
+ /*
+ * Skip the substitution if the variable
+ * name isn't part of the pattern.
+ */
+ v++;
+ continue;
+ }
+
+ /* Use pcrs to replace the variable with its value. */
+ d = pcrs_get_delimiter(v->value);
+ if ('\0' == d)
+ {
+ /* No proper delimiter found */
+ *error = PCRS_ERR_CMDSYNTAX;
+ return NULL;
+ }
+
+ /*
+ * Variable names are supposed to contain alpha
+ * numerical characters plus '_' only.
+ */
+ assert(NULL == strchr(v->name, d));
+
+ ret = snprintf(buf, sizeof(buf), "s%c\\$%s%c%s%cgT", d, v->name, d, v->value, d);
+ assert(ret >= 0);
+ if (ret >= sizeof(buf))
+ {
+ /*
+ * Value didn't completely fit into buffer,
+ * overwrite the end of the substitution text
+ * with a truncation message and close the pattern
+ * properly.
+ */
+ const size_t trailer_size = sizeof(warning) + 3; /* 3 for d + "gT" */
+ char *trailer_start = buf + sizeof(buf) - trailer_size;
+
+ ret = snprintf(trailer_start, trailer_size, "%s%cgT", warning, d);
+ assert(ret == trailer_size - 1);
+ assert(sizeof(buf) == strlen(buf) + 1);
+ truncation = 1;
+ }
+
+ pcrs_command_tmp = pcrs_execute_single_command(pcrs_command, buf, error);
+ if (NULL == pcrs_command_tmp)
+ {
+ return NULL;
+ }
+
+ if (pcrs_command != original_pcrs_command)
+ {
+ freez(pcrs_command);
+ }
+ pcrs_command = pcrs_command_tmp;
+
+ v++;
+ }
+
+ job = pcrs_compile_command(pcrs_command, error);
+ if (pcrs_command != original_pcrs_command)
+ {
+ freez(pcrs_command);
+ }
+
+ if (truncation)
+ {
+ *error = PCRS_WARN_TRUNCATION;
+ }
+
+ return job;
+
+}
+
+
/*
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projects / privoxy.git / blobdiff