X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=pcrs.c;h=45a471b9b5a0cbf7711535b56c0c014e41964d47;hp=f48e3dae09f73a96b35b9379065c43d8b438baa9;hb=6f113c5cca4a173f76c1000a093fc4a8618e3668;hpb=d31bd7fabbfa586b5905df0eb3e0e32e76895555 diff --git a/pcrs.c b/pcrs.c index f48e3dae..45a471b9 100644 --- a/pcrs.c +++ b/pcrs.c @@ -1,77 +1,109 @@ -const char pcrs_rcs[] = "$Id: pcrs.c,v 1.6 2001/06/03 19:12:45 oes Exp $"; +const char pcrs_rcs[] = "$Id: pcrs.c,v 1.18 2002/03/08 14:17:14 oes Exp $"; /********************************************************************* * * File : $Source: /cvsroot/ijbswa/current/pcrs.c,v $ * - * Purpose : This is the alpha release of libpcrs. It is only published - * at this early stage of development, because it is - * needed for a new feature in JunkBuster. + * Purpose : pcrs is a supplement to the pcre library by Philip Hazel + * and adds Perl-style substitution. That + * is, it mimics Perl's 's' operator. See pcrs(3) for details. * - * While no inconsistencies, memory leaks or functional bugs - * are known at this time, there *could* be plenty ;-). Also, - * Many pcre-specific options are not yet supported, and - * error handling needs improvement. - * - * 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 ;-) - * - * Short note: I addition to perl's options, 'U' for ungreedy - * and 't' for trivial (i.e.: ignore backrefs in the substitute) - * are supported. * * Copyright : Written and Copyright (C) 2000, 2001 by Andreas S. Oesterhelt * * * 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 1.18 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. + * + * Revision 1.9 2001/07/18 17:27:00 oes + * Changed interface; Cosmetics + * + * Revision 1.8 2001/06/29 21:45:41 oes + * Indentation, CRLF->LF, Tab-> Space + * + * Revision 1.7 2001/06/29 13:33:04 oes + * - Cleaned up, renamed and reordered functions, + * improved comments + * - Removed my_strsep + * - Replaced globalflag with a general flags int + * that holds PCRS_GLOBAL, PCRS_SUCCESS, and PCRS_TRIVIAL + * - Introduced trivial option that will prevent pcrs + * from honouring backreferences in the substitute, + * which is useful for large substitutes that are + * red in from somewhere and saves the pain of escaping + * the backrefs + * - Introduced convenience function pcrs_free_joblist() + * - Split pcrs_make_job() into pcrs_compile(), which still + * takes a complete s/// comand as argument and parses it, + * and a new function pcrs_make_job, which takes the + * three separate components. This should make for a + * much friendlier frontend. + * - Removed create_pcrs_job() which was useless + * - Fixed a bug in pcrs_execute + * - Success flag is now handled by pcrs instead of user + * * Revision 1.6 2001/06/03 19:12:45 oes * added FIXME * * Revision 1.5 2001/05/29 09:50:24 jongfoster - * Unified blocklist/imagelist/permissionslist. - * File format is still under discussion, but the internal changes - * are (mostly) done. - * - * Also modified interceptor behaviour: - * - We now intercept all URLs beginning with one of the following - * prefixes (and *only* these prefixes): - * * http://i.j.b/ - * * http://ijbswa.sf.net/config/ - * * http://ijbswa.sourceforge.net/config/ - * - New interceptors "home page" - go to http://i.j.b/ to see it. - * - Internal changes so that intercepted and fast redirect pages - * are not replaced with an image. - * - Interceptors now have the option to send a binary page direct - * to the client. (i.e. ijb-send-banner uses this) - * - Implemented show-url-info interceptor. (Which is why I needed - * the above interceptors changes - a typical URL is - * "http://i.j.b/show-url-info?url=www.somesite.com/banner.gif". - * The previous mechanism would not have intercepted that, and - * if it had been intercepted then it then it would have replaced - * it with an image.) + * (Fixed one int -> size_t) * * Revision 1.4 2001/05/25 14:12:40 oes * Fixed bug: Empty substitutes now detected @@ -81,48 +113,12 @@ const char pcrs_rcs[] = "$Id: pcrs.c,v 1.6 2001/06/03 19:12:45 oes Exp $"; * * Revision 1.2 2001/05/22 18:46:04 oes * - * - Enabled filtering banners by size rather than URL - * by adding patterns that replace all standard banner - * sizes with the "Junkbuster" gif to the re_filterfile - * - * - Enabled filtering WebBugs by providing a pattern - * which kills all 1x1 images - * - * - Added support for PCRE_UNGREEDY behaviour to pcrs, + * Added support for PCRE_UNGREEDY behaviour to pcrs, * which is selected by the (nonstandard and therefore * capital) letter 'U' in the option string. * It causes the quantifiers to be ungreedy by default. * Appending a ? turns back to greedy (!). * - * - Added a new interceptor ijb-send-banner, which - * sends back the "Junkbuster" gif. Without imagelist or - * MSIE detection support, or if tinygif = 1, or the - * URL isn't recognized as an imageurl, a lame HTML - * explanation is sent instead. - * - * - Added new feature, which permits blocking remote - * script redirects and firing back a local redirect - * to the browser. - * The feature is conditionally compiled, i.e. it - * can be disabled with --disable-fast-redirects, - * plus it must be activated by a "fast-redirects" - * line in the config file, has its own log level - * and of course wants to be displayed by show-proxy-args - * Note: Boy, all the #ifdefs in 1001 locations and - * all the fumbling with configure.in and acconfig.h - * were *way* more work than the feature itself :-( - * - * - Because a generic redirect template was needed for - * this, tinygif = 3 now uses the same. - * - * - Moved GIFs, and other static HTTP response templates - * to project.h - * - * - Some minor fixes - * - * - Removed some >400 CRs again (Jon, you really worked - * a lot! ;-) - * * Revision 1.1.1.1 2001/05/15 13:59:02 oes * Initial import of version 2.9.3 source tree * @@ -132,13 +128,71 @@ const char pcrs_rcs[] = "$Id: pcrs.c,v 1.6 2001/06/03 19:12:45 oes Exp $"; #include #include +#include + #include "pcrs.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); /********************************************************************* * - * Function : pcrs_compile_perl_options + * 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"; + + /* 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"; + + /* What's that? */ + default: return "Unknown error"; + } + } + /* error >= 0: No error */ + return "(pcrs:) Everything's just fine. Thanks for asking."; + +} + + +/********************************************************************* + * + * Function : pcrs_parse_perl_options * * Description : This function parses a string containing the options to * Perl's s/// operator. It returns an integer that is the @@ -155,16 +209,19 @@ const char pcrs_h_rcs[] = PCRS_H_VERSION; * Returns : option integer suitable for pcre * *********************************************************************/ -int pcrs_compile_perl_options(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 'e': break; + case 'e': break; /* ToDo ;-) */ case 'g': *flags |= PCRS_GLOBAL; break; case 'i': rc |= PCRE_CASELESS; break; case 'm': rc |= PCRE_MULTILINE; break; @@ -172,8 +229,8 @@ int pcrs_compile_perl_options(char *optstring, int *flags) 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; @@ -193,7 +250,11 @@ int pcrs_compile_perl_options(char *optstring, int *flags) * Parameters : * 1 : replacement = replacement part of s/// operator * in perl syntax - * 2 : errptr = pointer to an integer in which error + * 2 : trivialflag = Flag that causes backreferences to be + * ignored. + * 3 : capturecount = Number of capturing subpatterns in + * the pattern. Needed for $+ handling. + * 4 : errptr = pointer to an integer in which error * conditions can be returned. * * Returns : pcrs_substitute data structure, or NULL if an @@ -201,89 +262,178 @@ int pcrs_compile_perl_options(char *optstring, int *flags) * the reason. * *********************************************************************/ -pcrs_substitute *pcrs_compile_replacement(char *replacement, int trivialflag, int *errptr) +static pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialflag, int capturecount, int *errptr) { - int length, i, k = 0, l = 0, quoted = 0, idx; - char *text, *num_ptr, *numbers = "0123456789"; + int i, k, l, quoted; + size_t length; + char *text; pcrs_substitute *r; - r = (pcrs_substitute *)malloc(sizeof(pcrs_substitute)); - if (r == NULL) return NULL; - memset(r, '\0', sizeof(pcrs_substitute)); + i = k = l = quoted = 0; - text = strdup(replacement); /* must be free()d by caller */ - if (text == NULL) + /* + * Sanity check + */ + if (NULL == replacement) + { + replacement = ""; + } + + /* + * Get memory or fail + */ + if (NULL == (r = (pcrs_substitute *)malloc(sizeof(pcrs_substitute)))) { *errptr = PCRS_ERR_NOMEM; - free(r); return NULL; } + memset(r, '\0', sizeof(pcrs_substitute)); length = strlen(replacement); + if (NULL == (text = (char *)malloc(length + 1))) + { + free(r); + *errptr = PCRS_ERR_NOMEM; + return NULL; + } + memset(text, '\0', length + 1); + + + /* + * In trivial mode, just copy the substitute text + */ if (trivialflag) { - k = length; + text = strncpy(text, replacement, length + 1); + k = length; } + + /* + * Else, parse, cut out and record all backreferences + */ else - { - for (i=0; i < length; i++) + { + while (i < (int)length) { - /* Backslash treatment */ + /* Quoting */ if (replacement[i] == '\\') { if (quoted) { - text[k++] = replacement[i]; + text[k++] = replacement[i++]; quoted = 0; } else { - quoted = 1; + 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 + { + quoted = 1; + i++; + } } continue; } - /* Dollar treatment */ - if (replacement[i] == '$' && !quoted && i < length - 1) + /* Backreferences */ + if (replacement[i] == '$' && !quoted && i < (int)(length - 1)) { - if (strchr("0123456789&", replacement[i + 1]) == NULL) + char *symbol, symbols[] = "'`+&"; + r->block_length[l] = k - r->block_offset[l]; + + /* Numerical backreferences */ + if (isdigit((int)replacement[i + 1])) { - text[k++] = 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; + } } - else + + /* Symbolic backreferences: */ + else if (NULL != (symbol = strchr(symbols, replacement[i + 1]))) { - r->block_length[l] = k - r->block_offset[l]; - r->backref[l] = 0; - if (replacement[i + 1] != '&') + + if (symbol - symbols == 2) /* $+ */ { - while ((num_ptr = strchr(numbers, replacement[++i])) != NULL && i < length) - { - idx = num_ptr - numbers; - r->backref[l] = r->backref[l] * 10 + idx; - } - i--; + r->backref[l] = capturecount; } - else - i++; - if (r->backref[l] < PCRS_MAX_SUBMATCHES) - r->backref_count[r->backref[l]] += 1; - l++; - r->block_offset[l] = k; + else if (symbol - symbols == 3) /* $& */ + { + r->backref[l] = 0; + } + else /* $' or $` */ + { + r->backref[l] = PCRS_MAX_SUBMATCHES + 1 - (symbol - symbols); + } + i += 2; + } + + /* Invalid backref -> plain '$' */ + else + { + goto plainchar; } + + /* Valid and in range? -> record */ + if (r->backref[l] < PCRS_MAX_SUBMATCHES + 2) + { + r->backref_count[r->backref[l]] += 1; + r->block_offset[++l] = k; + } + else + { + *errptr = PCRS_WARN_BADREF; + } continue; } - - /* Plain char treatment */ - text[k++] = replacement[i]; + +plainchar: + /* Plain chars are copied */ + text[k++] = replacement[i++]; quoted = 0; } - } /* -END- if (!trivialflag) */ + } /* -END- if (!trivialflag) */ - text[k] = '\0'; + /* + * Finish & return + */ r->text = text; r->backrefs = l; r->block_length[l] = k - r->block_offset[l]; + return r; } @@ -294,8 +444,7 @@ pcrs_substitute *pcrs_compile_replacement(char *replacement, int trivialflag, in * Function : pcrs_free_job * * Description : Frees the memory used by a pcrs_job struct and its - * dependant structures. Returns a pointer to the next - * job, if there was any, or NULL otherwise. + * dependant structures. * * Parameters : * 1 : job = pointer to the pcrs_job structure to be freed @@ -328,6 +477,7 @@ pcrs_job *pcrs_free_job(pcrs_job *job) } + /********************************************************************* * * Function : pcrs_free_joblist @@ -353,11 +503,12 @@ void pcrs_free_joblist(pcrs_job *joblist) /********************************************************************* * - * Function : pcrs_compile + * Function : pcrs_compile_command * - * Description : Main entry point. Takes a string with a Perl-style - * s/// command and returns a corresponding pcrs_job, - * or NULL if compiling the job fails at any stage. + * Description : Parses a string with a Perl-style s/// command, + * calls pcrs_compile, and returns a corresponding + * pcrs_job, or NULL if parsing or compiling the job + * fails. * * Parameters : * 1 : command = string with perl-style s/// command @@ -369,76 +520,79 @@ void pcrs_free_joblist(pcrs_job *joblist) * has the reason. * *********************************************************************/ -pcrs_job *pcrs_compile(char *command, int *errptr) +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 */ limit = strlen(command); if (limit < 4) - { + { *errptr = PCRS_ERR_CMDSYNTAX; return NULL; } 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[0][k++] = '\0'; tokens[++l] = tokens[0] + k; - continue; + 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; } - /* * Syntax error ? */ if (l != 3) { - *errptr = PCRS_ERR_CMDSYNTAX; + *errptr = PCRS_ERR_CMDSYNTAX; free(tokens[0]); return NULL; } - - newjob = pcrs_make_job(tokens[1], tokens[2], tokens[3], errptr); + + newjob = pcrs_compile(tokens[1], tokens[2], tokens[3], errptr); free(tokens[0]); return newjob; - + } /********************************************************************* * - * Function : pcrs_make_job + * Function : pcrs_compile * * Description : Takes the three arguments to a perl s/// command * and compiles a pcrs_job structure from them. @@ -455,18 +609,21 @@ pcrs_job *pcrs_compile(char *command, int *errptr) * has the reason. * *********************************************************************/ -pcrs_job *pcrs_make_job(char *pattern, char *substitute, char *options, int *errptr) +pcrs_job *pcrs_compile(const char *pattern, const char *substitute, const char *options, int *errptr) { pcrs_job *newjob; int flags; + int capturecount; const char *error; + *errptr = 0; + /* * Handle NULL arguments */ if (pattern == NULL) pattern = ""; if (substitute == NULL) substitute = ""; - if (options == NULL) options = ""; + /* * Get and init memory @@ -482,7 +639,7 @@ pcrs_job *pcrs_make_job(char *pattern, char *substitute, char *options, int *err /* * Evaluate the options */ - newjob->options = pcrs_compile_perl_options(options, &flags); + newjob->options = pcrs_parse_perl_options(options, &flags); newjob->flags = flags; @@ -510,10 +667,21 @@ pcrs_job *pcrs_make_job(char *pattern, char *substitute, char *options, int *err } + /* + * Determine the number of capturing subpatterns. + * This is needed for handling $+ in the substitute. + */ + if (0 > (*errptr = pcre_fullinfo(newjob->pattern, newjob->hints, PCRE_INFO_CAPTURECOUNT, &capturecount))) + { + pcrs_free_job(newjob); + return NULL; + } + + /* * Compile the substitute */ - if (NULL == (newjob->substitute = pcrs_compile_replacement(substitute, newjob->flags & PCRS_TRIVIAL, errptr))) + if (NULL == (newjob->substitute = pcrs_compile_replacement(substitute, newjob->flags & PCRS_TRIVIAL, capturecount, errptr))) { pcrs_free_job(newjob); return NULL; @@ -524,16 +692,73 @@ pcrs_job *pcrs_make_job(char *pattern, char *substitute, char *options, int *err } +/********************************************************************* + * + * 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. + * + * Parameters : + * 1 : joblist = the chained list of pcrs_jobs to be executed + * 2 : subject = the subject string + * 3 : subject_length = the subject's length + * INCLUDING the terminating zero, if string! + * 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 failiure, the (negative) pcre error code describing the + * failiure, 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; + 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. * * Parameters : * 1 : job = the pcrs_job to be executed @@ -541,26 +766,30 @@ pcrs_job *pcrs_make_job(char *pattern, char *substitute, char *options, int *err * 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 + * 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 failiure, the (negative) pcre error code describing the + * failiure, 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, 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; - pcrs_match matches[PCRS_MAX_MATCHES]; + submatches, + max_matches = PCRS_MAX_MATCH_INIT; + size_t newsize; + pcrs_match *matches, *dummy; char *result_offset; offset = i = k = 0; /* - * Sanity check + * Sanity check & memory allocation */ if (job == NULL || job->pattern == NULL || job->substitute == NULL) { @@ -568,18 +797,26 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result return(PCRS_ERR_BADJOB); } - + if (NULL == (matches = (pcrs_match *)malloc(max_matches * sizeof(pcrs_match)))) + { + *result = NULL; + return(PCRS_ERR_NOMEM); + } + memset(matches, '\0', max_matches * sizeof(pcrs_match)); + + /* * Find the pattern and calculate the space - * requirements for the result (newsize) + * 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; + 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]; @@ -592,12 +829,35 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result /* plus replacement text size minus match text size */ newsize += strlen(job->substitute->text) - 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]; + + /* 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]; + + /* Storage for matches exhausted? -> Extend! */ + if (++i >= max_matches) + { + max_matches = (int)(max_matches * PCRS_MAX_MATCH_GROW); + if (NULL == (dummy = (pcrs_match *)realloc(matches, max_matches * sizeof(pcrs_match)))) + { + free(matches); + *result = NULL; + return(PCRS_ERR_NOMEM); + } + matches = dummy; + } + /* Non-global search or limit reached? */ - if (++i >= PCRS_MAX_MATCHES || !(job->flags & PCRS_GLOBAL) ) break; + 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; @@ -605,8 +865,12 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result else offset = offsets[1]; } - /* Pass pcre error through if failiure*/ - if (submatches < -1) return submatches; + /* Pass pcre error through if (bad) failiure */ + if (submatches < PCRE_ERROR_NOMATCH) + { + free(matches); + return submatches; + } matches_found = i; @@ -615,6 +879,7 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result */ if ((*result = (char *)malloc(newsize)) == NULL) /* must be free()d by caller */ { + free(matches); return PCRS_ERR_NOMEM; } @@ -625,27 +890,27 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result 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]); result_offset += job->substitute->block_length[k]; - /* ..plus, if it's not the last chunk (i.e.: There IS a backref).. */ + /* ..plus, if it's not the last chunk, i.e.: There *is* a backref.. */ if (k != job->substitute->backrefs - /* ..and a nonempty match.. */ - && matches[i].submatch_length[job->substitute->backref[k]] > 0 - /* ..and in legal range, ... */ - && job->substitute->backref[k] <= PCRS_MAX_SUBMATCHES) + /* ..in legal range.. */ + && job->substitute->backref[k] < PCRS_MAX_SUBMATCHES + 2 + /* ..and referencing a nonempty match.. */ + && matches[i].submatch_length[job->substitute->backref[k]] > 0) { - /* copy the submatch that is ref'd. */ + /* ..copy the submatch that is ref'd. */ memcpy( result_offset, subject + matches[i].submatch_offset[job->substitute->backref[k]], @@ -661,6 +926,7 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result memcpy(result_offset, subject + offset, subject_length - offset); *result_length = newsize; + free(matches); return matches_found; }