X-Git-Url: http://www.privoxy.org/gitweb/?p=privoxy.git;a=blobdiff_plain;f=pcrs.c;h=0f5145aa5f975dfd7b200d4dcf4cc51483af96e8;hp=886cc07c8e155c56fd623e89b8044389d562fe4f;hb=f3e87d9a4e656286a271d5ad822d65301e2ef0f4;hpb=4101601d163aad202638f7bb002bdc4fa71649d3 diff --git a/pcrs.c b/pcrs.c index 886cc07c..0f5145aa 100644 --- a/pcrs.c +++ b/pcrs.c @@ -1,106 +1,132 @@ -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 1.36 2011/03/03 14:49:08 fabiankeil Exp $"; /********************************************************************* * * File : $Source: /cvsroot/ijbswa/current/pcrs.c,v $ * - * Purpose : pcrs is a supplement to the brilliant pcre library by Philip - * Hazel 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 + * 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additional functions and bug + * fixes that aren't part of the latest official pcrs package + * (which apparently is no longer maintained).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 * * + * Copyright (C) 2006, 2007 Fabian Keil + * * 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 1.10 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 - * (Fixed one int -> size_t) - * - * Revision 1.4 2001/05/25 14:12:40 oes - * Fixed bug: Empty substitutes now detected - * - * Revision 1.3 2001/05/25 11:03:55 oes - * Added sanity check for NULL jobs to pcrs_exec_substitution - * - * Revision 1.2 2001/05/22 18:46:04 oes - * - * 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 (!). - * - * Revision 1.1.1.1 2001/05/15 13:59:02 oes - * Initial import of version 2.9.3 source tree - * - * *********************************************************************/ - -#include + #include +#include +#include + +/* + * 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 + 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."; + +} + /********************************************************************* * @@ -121,12 +147,15 @@ const char pcrs_h_rcs[] = PCRS_H_VERSION; * 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]) { @@ -138,8 +167,8 @@ int pcrs_parse_perl_options(const 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; @@ -171,14 +200,23 @@ int pcrs_parse_perl_options(const char *optstring, int *flags) * 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 */ @@ -197,7 +235,7 @@ pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialfl *errptr = PCRS_ERR_NOMEM; return NULL; } - memset(r, '\0', length + 1); + memset(text, '\0', length + 1); /* @@ -206,7 +244,7 @@ pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialfl if (trivialflag) { text = strncpy(text, replacement, length + 1); - k = length; + k = (int)length; } /* @@ -214,7 +252,7 @@ pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialfl */ else { - while(i < length) + while (i < (int)length) { /* Quoting */ if (replacement[i] == '\\') @@ -226,25 +264,74 @@ pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialfl } 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: */ @@ -261,7 +348,7 @@ pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialfl } else /* $' or $` */ { - r->backref[l] = PCRS_MAX_SUBMATCHES + 1 - (symbol - symbols); + r->backref[l] = (int)(PCRS_MAX_SUBMATCHES + 1 - (symbol - symbols)); } i += 2; } @@ -278,6 +365,10 @@ pcrs_substitute *pcrs_compile_replacement(const char *replacement, int trivialfl r->backref_count[r->backref[l]] += 1; r->block_offset[++l] = k; } + else + { + *errptr = PCRS_WARN_BADREF; + } continue; } @@ -293,7 +384,8 @@ plainchar: */ 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; @@ -305,7 +397,7 @@ plainchar: * Function : pcrs_free_job * * Description : Frees the memory used by a pcrs_job struct and its - * dependant structures. + * dependent structures. * * Parameters : * 1 : job = pointer to the pcrs_job structure to be freed @@ -383,13 +475,14 @@ void pcrs_free_joblist(pcrs_job *joblist) *********************************************************************/ 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; - + + k = l = 0; + /* * Tokenize the perl command */ @@ -401,33 +494,36 @@ pcrs_job *pcrs_compile_command(const char *command, int *errptr) } 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; } /* @@ -439,11 +535,11 @@ pcrs_job *pcrs_compile_command(const char *command, int *errptr) free(tokens[0]); return NULL; } - + newjob = pcrs_compile(tokens[1], tokens[2], tokens[3], errptr); free(tokens[0]); return newjob; - + } @@ -473,13 +569,13 @@ pcrs_job *pcrs_compile(const char *pattern, const char *substitute, const char * int capturecount; const char *error; + *errptr = 0; /* * Handle NULL arguments */ if (pattern == NULL) pattern = ""; if (substitute == NULL) substitute = ""; - if (options == NULL) options = ""; /* @@ -549,102 +645,165 @@ pcrs_job *pcrs_compile(const char *pattern, const char *substitute, const char * } +/********************************************************************* + * + * 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; + 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; - offset = i = k = 0; + offset = i = 0; /* * 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; @@ -653,9 +812,12 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result 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; @@ -663,8 +825,8 @@ 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) + /* Pass pcre error through if (bad) failiure */ + if (submatches < PCRE_ERROR_NOMATCH) { free(matches); return submatches; @@ -673,13 +835,18 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result /* - * 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'; + } /* @@ -688,14 +855,14 @@ 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]); @@ -705,7 +872,9 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result 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. */ @@ -717,11 +886,11 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result 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); @@ -730,6 +899,268 @@ int pcrs_execute(pcrs_job *job, char *subject, int subject_length, char **result } +#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 : pcrs_command = The dynamic pcrs command to compile + * 2 : v = NULL terminated array of variables and their values. + * 3 : 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; + +} + + /* Local Variables: tab-width: 3