root/ext/pcre/php_pcre.c

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DEFINITIONS

This source file includes following definitions.
  1. ZEND_DECLARE_MODULE_GLOBALS
  2. php_free_pcre_cache
  3. PHP_GINIT_FUNCTION
  4. PHP_GSHUTDOWN_FUNCTION
  5. PHP_INI_BEGIN
  6. PHP_MINIT_FUNCTION
  7. PHP_MSHUTDOWN_FUNCTION
  8. pcre_clean_cache
  9. pcre_get_compiled_regex_cache
  10. pcre_get_compiled_regex
  11. pcre_get_compiled_regex_ex
  12. add_offset_pair
  13. php_do_pcre_match
  14. php_pcre_match_impl
  15. PHP_FUNCTION
  16. PHP_FUNCTION
  17. preg_get_backref
  18. preg_do_repl_func
  19. preg_do_eval
  20. php_pcre_replace
  21. php_pcre_replace_impl
  22. php_replace_in_subject
  23. preg_replace_impl
  24. PHP_FUNCTION
  25. PHP_FUNCTION
  26. PHP_FUNCTION
  27. php_pcre_split_impl
  28. PHP_FUNCTION
  29. PHP_FUNCTION
  30. php_pcre_grep_impl
  31. PHP_FUNCTION

/*
   +----------------------------------------------------------------------+
   | PHP Version 5                                                        |
   +----------------------------------------------------------------------+
   | Copyright (c) 1997-2008 The PHP Group                                |
   +----------------------------------------------------------------------+
   | This source file is subject to version 3.01 of the PHP license,      |
   | that is bundled with this package in the file LICENSE, and is        |
   | available through the world-wide-web at the following url:           |
   | http://www.php.net/license/3_01.txt                                  |
   | If you did not receive a copy of the PHP license and are unable to   |
   | obtain it through the world-wide-web, please send a note to          |
   | license@php.net so we can mail you a copy immediately.               |
   +----------------------------------------------------------------------+
   | Author: Andrei Zmievski <andrei@php.net>                             |
   +----------------------------------------------------------------------+
 */

/* $Id: php_pcre.c,v 1.168.2.9.2.25 2008/02/20 22:08:18 felipe Exp $ */

#include "php.h"
#include "php_ini.h"
#include "php_globals.h"
#include "php_pcre.h"
#include "ext/standard/info.h"
#include "ext/standard/php_smart_str.h"

#if HAVE_PCRE || HAVE_BUNDLED_PCRE

#include "ext/standard/php_string.h"

#define PREG_PATTERN_ORDER                      1
#define PREG_SET_ORDER                          2
#define PREG_OFFSET_CAPTURE                     (1<<8)

#define PREG_SPLIT_NO_EMPTY                     (1<<0)
#define PREG_SPLIT_DELIM_CAPTURE        (1<<1)
#define PREG_SPLIT_OFFSET_CAPTURE       (1<<2)

#define PREG_REPLACE_EVAL                       (1<<0)

#define PREG_GREP_INVERT                        (1<<0)

#define PCRE_CACHE_SIZE 4096

enum {
        PHP_PCRE_NO_ERROR = 0,
        PHP_PCRE_INTERNAL_ERROR,
        PHP_PCRE_BACKTRACK_LIMIT_ERROR,
        PHP_PCRE_RECURSION_LIMIT_ERROR,
        PHP_PCRE_BAD_UTF8_ERROR
};


ZEND_DECLARE_MODULE_GLOBALS(pcre)


static void pcre_handle_exec_error(int pcre_code TSRMLS_DC) /* {{{ */
{
        int preg_code = 0;

        switch (pcre_code) {
                case PCRE_ERROR_MATCHLIMIT:
                        preg_code = PHP_PCRE_BACKTRACK_LIMIT_ERROR;
                        break;

                case PCRE_ERROR_RECURSIONLIMIT:
                        preg_code = PHP_PCRE_RECURSION_LIMIT_ERROR;
                        break;

                case PCRE_ERROR_BADUTF8:
                        preg_code = PHP_PCRE_BAD_UTF8_ERROR;
                        break;

                default:
                        preg_code = PHP_PCRE_INTERNAL_ERROR;
                        break;
        }

        PCRE_G(error_code) = preg_code;
}
/* }}} */

static void php_free_pcre_cache(void *data) /* {{{ */
{
        pcre_cache_entry *pce = (pcre_cache_entry *) data;
        if (!pce) return;
        pefree(pce->re, 1);
        if (pce->extra) pefree(pce->extra, 1);
#if HAVE_SETLOCALE
        if ((void*)pce->tables) pefree((void*)pce->tables, 1);
        pefree(pce->locale, 1);
#endif
}
/* }}} */

static PHP_GINIT_FUNCTION(pcre) /* {{{ */
{
        zend_hash_init(&pcre_globals->pcre_cache, 0, NULL, php_free_pcre_cache, 1);
        pcre_globals->backtrack_limit = 0;
        pcre_globals->recursion_limit = 0;
        pcre_globals->error_code      = PHP_PCRE_NO_ERROR;
}
/* }}} */

static PHP_GSHUTDOWN_FUNCTION(pcre) /* {{{ */
{
        zend_hash_destroy(&pcre_globals->pcre_cache);
}
/* }}} */

PHP_INI_BEGIN()
        STD_PHP_INI_ENTRY("pcre.backtrack_limit", "100000", PHP_INI_ALL, OnUpdateLong, backtrack_limit, zend_pcre_globals, pcre_globals)
        STD_PHP_INI_ENTRY("pcre.recursion_limit", "100000", PHP_INI_ALL, OnUpdateLong, recursion_limit, zend_pcre_globals, pcre_globals)
PHP_INI_END()


/* {{{ PHP_MINFO_FUNCTION(pcre) */
static PHP_MINFO_FUNCTION(pcre)
{
        php_info_print_table_start();
        php_info_print_table_row(2, "PCRE (Perl Compatible Regular Expressions) Support", "enabled" );
        php_info_print_table_row(2, "PCRE Library Version", pcre_version() );
        php_info_print_table_end();

        DISPLAY_INI_ENTRIES();
}
/* }}} */

/* {{{ PHP_MINIT_FUNCTION(pcre) */
static PHP_MINIT_FUNCTION(pcre)
{
        REGISTER_INI_ENTRIES();
        
        REGISTER_LONG_CONSTANT("PREG_PATTERN_ORDER", PREG_PATTERN_ORDER, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_SET_ORDER", PREG_SET_ORDER, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_OFFSET_CAPTURE", PREG_OFFSET_CAPTURE, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_SPLIT_NO_EMPTY", PREG_SPLIT_NO_EMPTY, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_SPLIT_DELIM_CAPTURE", PREG_SPLIT_DELIM_CAPTURE, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_SPLIT_OFFSET_CAPTURE", PREG_SPLIT_OFFSET_CAPTURE, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_GREP_INVERT", PREG_GREP_INVERT, CONST_CS | CONST_PERSISTENT);

        REGISTER_LONG_CONSTANT("PREG_NO_ERROR", PHP_PCRE_NO_ERROR, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_INTERNAL_ERROR", PHP_PCRE_INTERNAL_ERROR, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_BACKTRACK_LIMIT_ERROR", PHP_PCRE_BACKTRACK_LIMIT_ERROR, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_RECURSION_LIMIT_ERROR", PHP_PCRE_RECURSION_LIMIT_ERROR, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("PREG_BAD_UTF8_ERROR", PHP_PCRE_BAD_UTF8_ERROR, CONST_CS | CONST_PERSISTENT);
        REGISTER_STRING_CONSTANT("PCRE_VERSION", (char *)pcre_version(), CONST_CS | CONST_PERSISTENT);

        return SUCCESS;
}
/* }}} */

/* {{{ PHP_MSHUTDOWN_FUNCTION(pcre) */
static PHP_MSHUTDOWN_FUNCTION(pcre)
{
        UNREGISTER_INI_ENTRIES();

        return SUCCESS;
}
/* }}} */

/* {{{ static pcre_clean_cache */
static int pcre_clean_cache(void *data, void *arg TSRMLS_DC)
{
        int *num_clean = (int *)arg;

        if (*num_clean > 0) {
                (*num_clean)--;
                return 1;
        } else {
                return 0;
        }
}
/* }}} */

/* {{{ pcre_get_compiled_regex_cache
 */
PHPAPI pcre_cache_entry* pcre_get_compiled_regex_cache(char *regex, int regex_len TSRMLS_DC)
{
        pcre                            *re = NULL;
        pcre_extra                      *extra;
        int                                      coptions = 0;
        int                                      soptions = 0;
        const char                      *error;
        int                                      erroffset;
        char                             delimiter;
        char                             start_delimiter;
        char                             end_delimiter;
        char                            *p, *pp;
        char                            *pattern;
        int                                      do_study = 0;
        int                                      poptions = 0;
        unsigned const char *tables = NULL;
#if HAVE_SETLOCALE
        char                            *locale = setlocale(LC_CTYPE, NULL);
#endif
        pcre_cache_entry        *pce;
        pcre_cache_entry         new_entry;

        /* Try to lookup the cached regex entry, and if successful, just pass
           back the compiled pattern, otherwise go on and compile it. */
        regex_len = strlen(regex);
        if (zend_hash_find(&PCRE_G(pcre_cache), regex, regex_len+1, (void **)&pce) == SUCCESS) {
                /*
                 * We use a quick pcre_info() check to see whether cache is corrupted, and if it
                 * is, we flush it and compile the pattern from scratch.
                 */
                if (pcre_info(pce->re, NULL, NULL) == PCRE_ERROR_BADMAGIC) {
                        zend_hash_clean(&PCRE_G(pcre_cache));
                } else {
#if HAVE_SETLOCALE
                        if (!strcmp(pce->locale, locale)) {
#endif
                                return pce;
#if HAVE_SETLOCALE
                        }
#endif
                }
        }
        
        p = regex;
        
        /* Parse through the leading whitespace, and display a warning if we
           get to the end without encountering a delimiter. */
        while (isspace((int)*(unsigned char *)p)) p++;
        if (*p == 0) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Empty regular expression");
                return NULL;
        }
        
        /* Get the delimiter and display a warning if it is alphanumeric
           or a backslash. */
        delimiter = *p++;
        if (isalnum((int)*(unsigned char *)&delimiter) || delimiter == '\\') {
                php_error_docref(NULL TSRMLS_CC,E_WARNING, "Delimiter must not be alphanumeric or backslash");
                return NULL;
        }

        start_delimiter = delimiter;
        if ((pp = strchr("([{< )]}> )]}>", delimiter)))
                delimiter = pp[5];
        end_delimiter = delimiter;

        if (start_delimiter == end_delimiter) {
                /* We need to iterate through the pattern, searching for the ending delimiter,
                   but skipping the backslashed delimiters.  If the ending delimiter is not
                   found, display a warning. */
                pp = p;
                while (*pp != 0) {
                        if (*pp == '\\' && pp[1] != 0) pp++;
                        else if (*pp == delimiter)
                                break;
                        pp++;
                }
                if (*pp == 0) {
                        php_error_docref(NULL TSRMLS_CC,E_WARNING, "No ending delimiter '%c' found", delimiter);
                        return NULL;
                }
        } else {
                /* We iterate through the pattern, searching for the matching ending
                 * delimiter. For each matching starting delimiter, we increment nesting
                 * level, and decrement it for each matching ending delimiter. If we
                 * reach the end of the pattern without matching, display a warning.
                 */
                int brackets = 1;       /* brackets nesting level */
                pp = p;
                while (*pp != 0) {
                        if (*pp == '\\' && pp[1] != 0) pp++;
                        else if (*pp == end_delimiter && --brackets <= 0)
                                break;
                        else if (*pp == start_delimiter)
                                brackets++;
                        pp++;
                }
                if (*pp == 0) {
                        php_error_docref(NULL TSRMLS_CC,E_WARNING, "No ending matching delimiter '%c' found", end_delimiter);
                        return NULL;
                }
        }
        
        /* Make a copy of the actual pattern. */
        pattern = estrndup(p, pp-p);

        /* Move on to the options */
        pp++;

        /* Parse through the options, setting appropriate flags.  Display
           a warning if we encounter an unknown modifier. */    
        while (*pp != 0) {
                switch (*pp++) {
                        /* Perl compatible options */
                        case 'i':       coptions |= PCRE_CASELESS;              break;
                        case 'm':       coptions |= PCRE_MULTILINE;             break;
                        case 's':       coptions |= PCRE_DOTALL;                break;
                        case 'x':       coptions |= PCRE_EXTENDED;              break;
                        
                        /* PCRE specific options */
                        case 'A':       coptions |= PCRE_ANCHORED;              break;
                        case 'D':       coptions |= PCRE_DOLLAR_ENDONLY;break;
                        case 'S':       do_study  = 1;                                  break;
                        case 'U':       coptions |= PCRE_UNGREEDY;              break;
                        case 'X':       coptions |= PCRE_EXTRA;                 break;
                        case 'u':       coptions |= PCRE_UTF8;                  break;

                        /* Custom preg options */
                        case 'e':       poptions |= PREG_REPLACE_EVAL;  break;
                        
                        case ' ':
                        case '\n':
                                break;

                        default:
                                php_error_docref(NULL TSRMLS_CC,E_WARNING, "Unknown modifier '%c'", pp[-1]);
                                efree(pattern);
                                return NULL;
                }
        }

#if HAVE_SETLOCALE
        if (strcmp(locale, "C"))
                tables = pcre_maketables();
#endif

        /* Compile pattern and display a warning if compilation failed. */
        re = pcre_compile(pattern,
                                          coptions,
                                          &error,
                                          &erroffset,
                                          tables);

        if (re == NULL) {
                php_error_docref(NULL TSRMLS_CC,E_WARNING, "Compilation failed: %s at offset %d", error, erroffset);
                efree(pattern);
                if (tables) {
                        pefree((void*)tables, 1);
                }
                return NULL;
        }

        /* If study option was specified, study the pattern and
           store the result in extra for passing to pcre_exec. */
        if (do_study) {
                extra = pcre_study(re, soptions, &error);
                if (extra) {
                        extra->flags |= PCRE_EXTRA_MATCH_LIMIT | PCRE_EXTRA_MATCH_LIMIT_RECURSION;
                }
                if (error != NULL) {
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Error while studying pattern");
                }
        } else {
                extra = NULL;
        }

        efree(pattern);

        /*
         * If we reached cache limit, clean out the items from the head of the list;
         * these are supposedly the oldest ones (but not necessarily the least used
         * ones).
         */
        if (zend_hash_num_elements(&PCRE_G(pcre_cache)) == PCRE_CACHE_SIZE) {
                int num_clean = PCRE_CACHE_SIZE / 8;
                zend_hash_apply_with_argument(&PCRE_G(pcre_cache), pcre_clean_cache, &num_clean TSRMLS_CC);
        }

        /* Store the compiled pattern and extra info in the cache. */
        new_entry.re = re;
        new_entry.extra = extra;
        new_entry.preg_options = poptions;
        new_entry.compile_options = coptions;
#if HAVE_SETLOCALE
        new_entry.locale = pestrdup(locale, 1);
        new_entry.tables = tables;
#endif
        zend_hash_update(&PCRE_G(pcre_cache), regex, regex_len+1, (void *)&new_entry,
                                                sizeof(pcre_cache_entry), (void**)&pce);

        return pce;
}
/* }}} */

/* {{{ pcre_get_compiled_regex
 */
PHPAPI pcre* pcre_get_compiled_regex(char *regex, pcre_extra **extra, int *preg_options TSRMLS_DC)
{
        pcre_cache_entry * pce = pcre_get_compiled_regex_cache(regex, strlen(regex) TSRMLS_CC);

        if (extra) {
                *extra = pce ? pce->extra : NULL;
        }
        if (preg_options) {
                *preg_options = pce ? pce->preg_options : 0;
        }
        
        return pce ? pce->re : NULL;
}
/* }}} */

/* {{{ pcre_get_compiled_regex_ex
 */
PHPAPI pcre* pcre_get_compiled_regex_ex(char *regex, pcre_extra **extra, int *preg_options, int *compile_options TSRMLS_DC)
{
        pcre_cache_entry * pce = pcre_get_compiled_regex_cache(regex, strlen(regex) TSRMLS_CC);
        
        if (extra) {
                *extra = pce ? pce->extra : NULL;
        }
        if (preg_options) {
                *preg_options = pce ? pce->preg_options : 0;
        }
        if (compile_options) {
                *compile_options = pce ? pce->compile_options : 0;
        }
        
        return pce ? pce->re : NULL;
}
/* }}} */

/* {{{ add_offset_pair */
static inline void add_offset_pair(zval *result, char *str, int len, int offset, char *name)
{
        zval *match_pair;

        ALLOC_ZVAL(match_pair);
        array_init(match_pair);
        INIT_PZVAL(match_pair);

        /* Add (match, offset) to the return value */
        add_next_index_stringl(match_pair, str, len, 1);
        add_next_index_long(match_pair, offset);
        
        if (name) {
                zval_add_ref(&match_pair);
                zend_hash_update(Z_ARRVAL_P(result), name, strlen(name)+1, &match_pair, sizeof(zval *), NULL);
        }
        zend_hash_next_index_insert(Z_ARRVAL_P(result), &match_pair, sizeof(zval *), NULL);
}
/* }}} */

static void php_do_pcre_match(INTERNAL_FUNCTION_PARAMETERS, int global) /* {{{ */
{
        /* parameters */
        char                     *regex;                        /* Regular expression */
        char                     *subject;                      /* String to match against */
        int                               regex_len;
        int                               subject_len;
        pcre_cache_entry *pce;                          /* Compiled regular expression */
        zval                     *subpats = NULL;       /* Array for subpatterns */
        long                      flags = 0;            /* Match control flags */
        long                      start_offset = 0;     /* Where the new search starts */

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, ((global) ? "ssz|ll" : "ss|zll"), &regex, &regex_len,
                                                          &subject, &subject_len, &subpats, &flags, &start_offset) == FAILURE) {
                RETURN_FALSE;
        }
        
        /* Compile regex or get it from cache. */
        if ((pce = pcre_get_compiled_regex_cache(regex, regex_len TSRMLS_CC)) == NULL) {
                RETURN_FALSE;
        }

        php_pcre_match_impl(pce, subject, subject_len, return_value, subpats, 
                global, ZEND_NUM_ARGS() >= 4, flags, start_offset TSRMLS_CC);
}
/* }}} */

/* {{{ php_pcre_match_impl() */
PHPAPI void php_pcre_match_impl(pcre_cache_entry *pce, char *subject, int subject_len, zval *return_value,
        zval *subpats, int global, int use_flags, long flags, long start_offset TSRMLS_DC)
{
        zval                    *result_set,            /* Holds a set of subpatterns after
                                                                                   a global match */
                                   **match_sets = NULL; /* An array of sets of matches for each
                                                                                   subpattern after a global match */
        pcre_extra              *extra = pce->extra;/* Holds results of studying */
        pcre_extra               extra_data;            /* Used locally for exec options */
        int                              exoptions = 0;         /* Execution options */
        int                              count = 0;                     /* Count of matched subpatterns */
        int                             *offsets;                       /* Array of subpattern offsets */
        int                              num_subpats;           /* Number of captured subpatterns */
        int                              size_offsets;          /* Size of the offsets array */
        int                              matched;                       /* Has anything matched */
        int                              g_notempty = 0;        /* If the match should not be empty */
        const char         **stringlist;                /* Holds list of subpatterns */
        char                    *match;                         /* The current match */
        char               **subpat_names = NULL;/* Array for named subpatterns */
        int                              i, rc;
        int                              subpats_order;         /* Order of subpattern matches */
        int                              offset_capture;    /* Capture match offsets: yes/no */

        /* Overwrite the passed-in value for subpatterns with an empty array. */
        if (subpats != NULL) {
                zval_dtor(subpats);
                array_init(subpats);
        }

        subpats_order = global ? PREG_PATTERN_ORDER : 0;

        if (use_flags) {
                offset_capture = flags & PREG_OFFSET_CAPTURE;

                /*
                 * subpats_order is pre-set to pattern mode so we change it only if
                 * necessary.
                 */
                if (flags & 0xff) {
                        subpats_order = flags & 0xff;
                }
                if ((global && (subpats_order < PREG_PATTERN_ORDER || subpats_order > PREG_SET_ORDER)) ||
                        (!global && subpats_order != 0)) {
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Invalid flags specified");
                        return;
                }
        } else {
                offset_capture = 0;
        }

        /* Negative offset counts from the end of the string. */
        if (start_offset < 0) {
                start_offset = subject_len + start_offset;
                if (start_offset < 0) {
                        start_offset = 0;
                }
        }

        if (extra == NULL) {
                extra_data.flags = PCRE_EXTRA_MATCH_LIMIT | PCRE_EXTRA_MATCH_LIMIT_RECURSION;
                extra = &extra_data;
        }
        extra->match_limit = PCRE_G(backtrack_limit);
        extra->match_limit_recursion = PCRE_G(recursion_limit);

        /* Calculate the size of the offsets array, and allocate memory for it. */
        rc = pcre_fullinfo(pce->re, extra, PCRE_INFO_CAPTURECOUNT, &num_subpats);
        if (rc < 0) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Internal pcre_fullinfo() error %d", rc);
                RETURN_FALSE;
        }
        num_subpats++;
        size_offsets = num_subpats * 3;
        offsets = (int *)safe_emalloc(size_offsets, sizeof(int), 0);

        /*
         * Build a mapping from subpattern numbers to their names. We will always
         * allocate the table, even though there may be no named subpatterns. This
         * avoids somewhat more complicated logic in the inner loops.
         */
        subpat_names = (char **)safe_emalloc(num_subpats, sizeof(char *), 0);
        memset(subpat_names, 0, sizeof(char *) * num_subpats);
        {
                int name_cnt = 0, name_size, ni = 0;
                char *name_table;
                unsigned short name_idx;

                rc = pcre_fullinfo(pce->re, extra, PCRE_INFO_NAMECOUNT, &name_cnt);
                if (rc < 0) {
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Internal pcre_fullinfo() error %d", rc);
                        efree(offsets);
                        efree(subpat_names);
                        RETURN_FALSE;
                }
                if (name_cnt > 0) {
                        int rc1, rc2;

                        rc1 = pcre_fullinfo(pce->re, extra, PCRE_INFO_NAMETABLE, &name_table);
                        rc2 = pcre_fullinfo(pce->re, extra, PCRE_INFO_NAMEENTRYSIZE, &name_size);
                        rc = rc2 ? rc2 : rc1;
                        if (rc < 0) {
                                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Internal pcre_fullinfo() error %d", rc);
                                efree(offsets);
                                efree(subpat_names);
                                RETURN_FALSE;
                        }

                        while (ni++ < name_cnt) {
                                name_idx = 0xff * name_table[0] + name_table[1];
                                subpat_names[name_idx] = name_table + 2;
                                if (is_numeric_string(subpat_names[name_idx], strlen(subpat_names[name_idx]), NULL, NULL, 0) > 0) {
                                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Numeric named subpatterns are not allowed");
                                        efree(offsets);
                                        efree(subpat_names);
                                        RETURN_FALSE;
                                }
                                name_table += name_size;
                        }
                }
        }

        /* Allocate match sets array and initialize the values. */
        if (global && subpats_order == PREG_PATTERN_ORDER) {
                match_sets = (zval **)safe_emalloc(num_subpats, sizeof(zval *), 0);
                for (i=0; i<num_subpats; i++) {
                        ALLOC_ZVAL(match_sets[i]);
                        array_init(match_sets[i]);
                        INIT_PZVAL(match_sets[i]);
                }
        }

        match = NULL;
        matched = 0;
        PCRE_G(error_code) = PHP_PCRE_NO_ERROR;
        
        do {
                /* Execute the regular expression. */
                count = pcre_exec(pce->re, extra, subject, subject_len, start_offset,
                                                  exoptions|g_notempty, offsets, size_offsets);

                /* Check for too many substrings condition. */  
                if (count == 0) {
                        php_error_docref(NULL TSRMLS_CC, E_NOTICE, "Matched, but too many substrings");
                        count = size_offsets/3;
                }

                /* If something has matched */
                if (count > 0) {
                        matched++;
                        match = subject + offsets[0];

                        /* If subpatterns array has been passed, fill it in with values. */
                        if (subpats != NULL) {
                                /* Try to get the list of substrings and display a warning if failed. */
                                if (pcre_get_substring_list(subject, offsets, count, &stringlist) < 0) {
                                        efree(subpat_names);
                                        efree(offsets);
                                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Get subpatterns list failed");
                                        RETURN_FALSE;
                                }

                                if (global) {   /* global pattern matching */
                                        if (subpats_order == PREG_PATTERN_ORDER) {
                                                /* For each subpattern, insert it into the appropriate array. */
                                                for (i = 0; i < count; i++) {
                                                        if (offset_capture) {
                                                                add_offset_pair(match_sets[i], (char *)stringlist[i],
                                                                                                offsets[(i<<1)+1] - offsets[i<<1], offsets[i<<1], NULL);
                                                        } else {
                                                                add_next_index_stringl(match_sets[i], (char *)stringlist[i],
                                                                                                           offsets[(i<<1)+1] - offsets[i<<1], 1);
                                                        }
                                                }
                                                /*
                                                 * If the number of captured subpatterns on this run is
                                                 * less than the total possible number, pad the result
                                                 * arrays with empty strings.
                                                 */
                                                if (count < num_subpats) {
                                                        for (; i < num_subpats; i++) {
                                                                add_next_index_string(match_sets[i], "", 1);
                                                        }
                                                }
                                        } else {
                                                /* Allocate the result set array */
                                                ALLOC_ZVAL(result_set);
                                                array_init(result_set);
                                                INIT_PZVAL(result_set);
                                                
                                                /* Add all the subpatterns to it */
                                                for (i = 0; i < count; i++) {
                                                        if (offset_capture) {
                                                                add_offset_pair(result_set, (char *)stringlist[i],
                                                                                                offsets[(i<<1)+1] - offsets[i<<1], offsets[i<<1], subpat_names[i]);
                                                        } else {
                                                                if (subpat_names[i]) {
                                                                        add_assoc_stringl(result_set, subpat_names[i], (char *)stringlist[i],
                                                                                                                   offsets[(i<<1)+1] - offsets[i<<1], 1);
                                                                }
                                                                add_next_index_stringl(result_set, (char *)stringlist[i],
                                                                                                           offsets[(i<<1)+1] - offsets[i<<1], 1);
                                                        }
                                                }
                                                /* And add it to the output array */
                                                zend_hash_next_index_insert(Z_ARRVAL_P(subpats), &result_set, sizeof(zval *), NULL);
                                        }
                                } else {                        /* single pattern matching */
                                        /* For each subpattern, insert it into the subpatterns array. */
                                        for (i = 0; i < count; i++) {
                                                if (offset_capture) {
                                                        add_offset_pair(subpats, (char *)stringlist[i],
                                                                                        offsets[(i<<1)+1] - offsets[i<<1],
                                                                                        offsets[i<<1], subpat_names[i]);
                                                } else {
                                                        if (subpat_names[i]) {
                                                                add_assoc_stringl(subpats, subpat_names[i], (char *)stringlist[i],
                                                                                                  offsets[(i<<1)+1] - offsets[i<<1], 1);
                                                        }
                                                        add_next_index_stringl(subpats, (char *)stringlist[i],
                                                                                                   offsets[(i<<1)+1] - offsets[i<<1], 1);
                                                }
                                        }
                                }

                                pcre_free((void *) stringlist);
                        }
                } else if (count == PCRE_ERROR_NOMATCH) {
                        /* If we previously set PCRE_NOTEMPTY after a null match,
                           this is not necessarily the end. We need to advance
                           the start offset, and continue. Fudge the offset values
                           to achieve this, unless we're already at the end of the string. */
                        if (g_notempty != 0 && start_offset < subject_len) {
                                offsets[0] = start_offset;
                                offsets[1] = start_offset + 1;
                        } else
                                break;
                } else {
                        pcre_handle_exec_error(count TSRMLS_CC);
                        break;
                }
                
                /* If we have matched an empty string, mimic what Perl's /g options does.
                   This turns out to be rather cunning. First we set PCRE_NOTEMPTY and try
                   the match again at the same point. If this fails (picked up above) we
                   advance to the next character. */
                g_notempty = (offsets[1] == offsets[0])? PCRE_NOTEMPTY | PCRE_ANCHORED : 0;
                
                /* Advance to the position right after the last full match */
                start_offset = offsets[1];
        } while (global);

        /* Add the match sets to the output array and clean up */
        if (global && subpats_order == PREG_PATTERN_ORDER) {
                for (i = 0; i < num_subpats; i++) {
                        if (subpat_names[i]) {
                                zend_hash_update(Z_ARRVAL_P(subpats), subpat_names[i],
                                                                 strlen(subpat_names[i])+1, &match_sets[i], sizeof(zval *), NULL);
                                ZVAL_ADDREF(match_sets[i]);
                        }
                        zend_hash_next_index_insert(Z_ARRVAL_P(subpats), &match_sets[i], sizeof(zval *), NULL);
                }
                efree(match_sets);
        }
        
        efree(offsets);
        efree(subpat_names);

        RETVAL_LONG(matched);
}
/* }}} */

/* {{{ proto int preg_match(string pattern, string subject [, array subpatterns [, int flags [, int offset]]])
   Perform a Perl-style regular expression match */
PHP_FUNCTION(preg_match)
{
        php_do_pcre_match(INTERNAL_FUNCTION_PARAM_PASSTHRU, 0);
}
/* }}} */

/* {{{ proto int preg_match_all(string pattern, string subject, array subpatterns [, int flags [, int offset]])
   Perform a Perl-style global regular expression match */
PHP_FUNCTION(preg_match_all)
{
        php_do_pcre_match(INTERNAL_FUNCTION_PARAM_PASSTHRU, 1);
}
/* }}} */

/* {{{ preg_get_backref
 */
static int preg_get_backref(char **str, int *backref)
{
        register char in_brace = 0;
        register char *walk = *str;

        if (walk[1] == 0)
                return 0;

        if (*walk == '$' && walk[1] == '{') {
                in_brace = 1;
                walk++;
        }
        walk++;

        if (*walk >= '0' && *walk <= '9') {
                *backref = *walk - '0';
                walk++;
        } else
                return 0;
        
        if (*walk && *walk >= '0' && *walk <= '9') {
                *backref = *backref * 10 + *walk - '0';
                walk++;
        }

        if (in_brace) {
                if (*walk == 0 || *walk != '}')
                        return 0;
                else
                        walk++;
        }
        
        *str = walk;
        return 1;       
}
/* }}} */

/* {{{ preg_do_repl_func
 */
static int preg_do_repl_func(zval *function, char *subject, int *offsets, int count, char **result TSRMLS_DC)
{
        zval            *retval_ptr;            /* Function return value */
        zval       **args[1];                   /* Argument to pass to function */
        zval            *subpats;                       /* Captured subpatterns */ 
        int                      result_len;            /* Return value length */
        int                      i;

        MAKE_STD_ZVAL(subpats);
        array_init(subpats);
        for (i = 0; i < count; i++)
                add_next_index_stringl(subpats, &subject[offsets[i<<1]], offsets[(i<<1)+1] - offsets[i<<1], 1);
        args[0] = &subpats;

        if (call_user_function_ex(EG(function_table), NULL, function, &retval_ptr, 1, args, 0, NULL TSRMLS_CC) == SUCCESS && retval_ptr) {
                convert_to_string_ex(&retval_ptr);
                *result = estrndup(Z_STRVAL_P(retval_ptr), Z_STRLEN_P(retval_ptr));
                result_len = Z_STRLEN_P(retval_ptr);
                zval_ptr_dtor(&retval_ptr);
        } else {
                if (!EG(exception)) {
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Unable to call custom replacement function");
                }
                result_len = offsets[1] - offsets[0];
                *result = estrndup(&subject[offsets[0]], result_len);
        }
        zval_dtor(subpats);
        FREE_ZVAL(subpats);

        return result_len;
}
/* }}} */

/* {{{ preg_do_eval
 */
static int preg_do_eval(char *eval_str, int eval_str_len, char *subject,
                                                int *offsets, int count, char **result TSRMLS_DC)
{
        zval             retval;                        /* Return value from evaluation */
        char            *eval_str_end,          /* End of eval string */
                                *match,                         /* Current match for a backref */
                                *esc_match,                     /* Quote-escaped match */
                                *walk,                          /* Used to walk the code string */
                                *segment,                       /* Start of segment to append while walking */
                                 walk_last;                     /* Last walked character */
        int                      match_len;                     /* Length of the match */
        int                      esc_match_len;         /* Length of the quote-escaped match */
        int                      result_len;            /* Length of the result of the evaluation */
        int                      backref;                       /* Current backref */
        char        *compiled_string_description;
        smart_str    code = {0};
        
        eval_str_end = eval_str + eval_str_len;
        walk = segment = eval_str;
        walk_last = 0;
        
        while (walk < eval_str_end) {
                /* If found a backreference.. */
                if ('\\' == *walk || '$' == *walk) {
                        smart_str_appendl(&code, segment, walk - segment);
                        if (walk_last == '\\') {
                                code.c[code.len-1] = *walk++;
                                segment = walk;
                                walk_last = 0;
                                continue;
                        }
                        segment = walk;
                        if (preg_get_backref(&walk, &backref)) {
                                if (backref < count) {
                                        /* Find the corresponding string match and substitute it
                                           in instead of the backref */
                                        match = subject + offsets[backref<<1];
                                        match_len = offsets[(backref<<1)+1] - offsets[backref<<1];
                                        if (match_len) {
                                                esc_match = php_addslashes_ex(match, match_len, &esc_match_len, 0, 1 TSRMLS_CC);
                                        } else {
                                                esc_match = match;
                                                esc_match_len = 0;
                                        }
                                } else {
                                        esc_match = "";
                                        esc_match_len = 0;
                                        match_len = 0;
                                }
                                smart_str_appendl(&code, esc_match, esc_match_len);

                                segment = walk;

                                /* Clean up and reassign */
                                if (esc_match_len)
                                        efree(esc_match);
                                continue;
                        }
                }
                walk++;
                walk_last = walk[-1];
        }
        smart_str_appendl(&code, segment, walk - segment);
        smart_str_0(&code);

        compiled_string_description = zend_make_compiled_string_description("regexp code" TSRMLS_CC);
        /* Run the code */
        if (zend_eval_string(code.c, &retval, compiled_string_description TSRMLS_CC) == FAILURE) {
                efree(compiled_string_description);
                php_error_docref(NULL TSRMLS_CC,E_ERROR, "Failed evaluating code: %s%s", PHP_EOL, code.c);
                /* zend_error() does not return in this case */
        }
        efree(compiled_string_description);
        convert_to_string(&retval);
        
        /* Save the return value and its length */
        *result = estrndup(Z_STRVAL(retval), Z_STRLEN(retval));
        result_len = Z_STRLEN(retval);
        
        /* Clean up */
        zval_dtor(&retval);
        smart_str_free(&code);
        
        return result_len;
}
/* }}} */

/* {{{ php_pcre_replace
 */
PHPAPI char *php_pcre_replace(char *regex,   int regex_len,
                                                          char *subject, int subject_len,
                                                          zval *replace_val, int is_callable_replace,
                                                          int *result_len, int limit, int *replace_count TSRMLS_DC)
{
        pcre_cache_entry        *pce;                       /* Compiled regular expression */

        /* Compile regex or get it from cache. */
        if ((pce = pcre_get_compiled_regex_cache(regex, regex_len TSRMLS_CC)) == NULL) {
                return NULL;
        }

        return php_pcre_replace_impl(pce, subject, subject_len, replace_val, 
                is_callable_replace, result_len, limit, replace_count TSRMLS_CC);
}
/* }}} */

/* {{{ php_pcre_replace_impl() */
PHPAPI char *php_pcre_replace_impl(pcre_cache_entry *pce, char *subject, int subject_len, zval *replace_val, 
        int is_callable_replace, int *result_len, int limit, int *replace_count TSRMLS_DC)
{
        pcre_extra              *extra = pce->extra;/* Holds results of studying */
        pcre_extra               extra_data;            /* Used locally for exec options */
        int                              exoptions = 0;         /* Execution options */
        int                              count = 0;                     /* Count of matched subpatterns */
        int                             *offsets;                       /* Array of subpattern offsets */
        int                              size_offsets;          /* Size of the offsets array */
        int                              new_len;                       /* Length of needed storage */
        int                              alloc_len;                     /* Actual allocated length */
        int                              eval_result_len=0;     /* Length of the eval'ed or
                                                                                   function-returned string */
        int                              match_len;                     /* Length of the current match */
        int                              backref;                       /* Backreference number */
        int                              eval;                          /* If the replacement string should be eval'ed */
        int                              start_offset;          /* Where the new search starts */
        int                              g_notempty=0;          /* If the match should not be empty */
        int                              replace_len=0;         /* Length of replacement string */
        char                    *result,                        /* Result of replacement */
                                        *replace=NULL,          /* Replacement string */
                                        *new_buf,                       /* Temporary buffer for re-allocation */
                                        *walkbuf,                       /* Location of current replacement in the result */
                                        *walk,                          /* Used to walk the replacement string */
                                        *match,                         /* The current match */
                                        *piece,                         /* The current piece of subject */
                                        *replace_end=NULL,      /* End of replacement string */
                                        *eval_result,           /* Result of eval or custom function */
                                         walk_last;                     /* Last walked character */
        int                              rc;

        if (extra == NULL) {
                extra_data.flags = PCRE_EXTRA_MATCH_LIMIT | PCRE_EXTRA_MATCH_LIMIT_RECURSION;
                extra = &extra_data;
        }
        extra->match_limit = PCRE_G(backtrack_limit);
        extra->match_limit_recursion = PCRE_G(recursion_limit);

        eval = pce->preg_options & PREG_REPLACE_EVAL;
        if (is_callable_replace) {
                if (eval) {
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Modifier /e cannot be used with replacement callback");
                        return NULL;
                }
        } else {
                replace = Z_STRVAL_P(replace_val);
                replace_len = Z_STRLEN_P(replace_val);
                replace_end = replace + replace_len;
        }

        /* Calculate the size of the offsets array, and allocate memory for it. */
        rc = pcre_fullinfo(pce->re, extra, PCRE_INFO_CAPTURECOUNT, &size_offsets);
        if (rc < 0) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Internal pcre_fullinfo() error %d", rc);
                return NULL;
        }
        size_offsets = (size_offsets + 1) * 3;
        offsets = (int *)safe_emalloc(size_offsets, sizeof(int), 0);
        
        alloc_len = 2 * subject_len + 1;
        result = safe_emalloc(alloc_len, sizeof(char), 0);

        /* Initialize */
        match = NULL;
        *result_len = 0;
        start_offset = 0;
        PCRE_G(error_code) = PHP_PCRE_NO_ERROR;
        
        while (1) {
                /* Execute the regular expression. */
                count = pcre_exec(pce->re, extra, subject, subject_len, start_offset,
                                                  exoptions|g_notempty, offsets, size_offsets);
                
                /* Check for too many substrings condition. */
                if (count == 0) {
                        php_error_docref(NULL TSRMLS_CC,E_NOTICE, "Matched, but too many substrings");
                        count = size_offsets/3;
                }

                piece = subject + start_offset;

                if (count > 0 && (limit == -1 || limit > 0)) {
                        if (replace_count) {
                                ++*replace_count;
                        }
                        /* Set the match location in subject */
                        match = subject + offsets[0];

                        new_len = *result_len + offsets[0] - start_offset; /* part before the match */
                        
                        /* If evaluating, do it and add the return string's length */
                        if (eval) {
                                eval_result_len = preg_do_eval(replace, replace_len, subject,
                                                                                           offsets, count, &eval_result TSRMLS_CC);
                                new_len += eval_result_len;
                        } else if (is_callable_replace) {
                                /* Use custom function to get replacement string and its length. */
                                eval_result_len = preg_do_repl_func(replace_val, subject, offsets,
                                                                                                        count, &eval_result TSRMLS_CC);
                                new_len += eval_result_len;
                        } else { /* do regular substitution */
                                walk = replace;
                                walk_last = 0;
                                while (walk < replace_end) {
                                        if ('\\' == *walk || '$' == *walk) {
                                                if (walk_last == '\\') {
                                                        walk++;
                                                        walk_last = 0;
                                                        continue;
                                                }
                                                if (preg_get_backref(&walk, &backref)) {
                                                        if (backref < count)
                                                                new_len += offsets[(backref<<1)+1] - offsets[backref<<1];
                                                        continue;
                                                }
                                        }
                                        new_len++;
                                        walk++;
                                        walk_last = walk[-1];
                                }
                        }

                        if (new_len + 1 > alloc_len) {
                                alloc_len = 1 + alloc_len + 2 * new_len;
                                new_buf = emalloc(alloc_len);
                                memcpy(new_buf, result, *result_len);
                                efree(result);
                                result = new_buf;
                        }
                        /* copy the part of the string before the match */
                        memcpy(&result[*result_len], piece, match-piece);
                        *result_len += match-piece;

                        /* copy replacement and backrefs */
                        walkbuf = result + *result_len;
                        
                        /* If evaluating or using custom function, copy result to the buffer
                         * and clean up. */
                        if (eval || is_callable_replace) {
                                memcpy(walkbuf, eval_result, eval_result_len);
                                *result_len += eval_result_len;
                                STR_FREE(eval_result);
                        } else { /* do regular backreference copying */
                                walk = replace;
                                walk_last = 0;
                                while (walk < replace_end) {
                                        if ('\\' == *walk || '$' == *walk) {
                                                if (walk_last == '\\') {
                                                        *(walkbuf-1) = *walk++;
                                                        walk_last = 0;
                                                        continue;
                                                }
                                                if (preg_get_backref(&walk, &backref)) {
                                                        if (backref < count) {
                                                                match_len = offsets[(backref<<1)+1] - offsets[backref<<1];
                                                                memcpy(walkbuf, subject + offsets[backref<<1], match_len);
                                                                walkbuf += match_len;
                                                        }
                                                        continue;
                                                }
                                        }
                                        *walkbuf++ = *walk++;
                                        walk_last = walk[-1];
                                }
                                *walkbuf = '\0';
                                /* increment the result length by how much we've added to the string */
                                *result_len += walkbuf - (result + *result_len);
                        }

                        if (limit != -1)
                                limit--;

                } else if (count == PCRE_ERROR_NOMATCH || limit == 0) {
                        /* If we previously set PCRE_NOTEMPTY after a null match,
                           this is not necessarily the end. We need to advance
                           the start offset, and continue. Fudge the offset values
                           to achieve this, unless we're already at the end of the string. */
                        if (g_notempty != 0 && start_offset < subject_len) {
                                offsets[0] = start_offset;
                                offsets[1] = start_offset + 1;
                                memcpy(&result[*result_len], piece, 1);
                                (*result_len)++;
                        } else {
                                new_len = *result_len + subject_len - start_offset;
                                if (new_len + 1 > alloc_len) {
                                        alloc_len = new_len + 1; /* now we know exactly how long it is */
                                        new_buf = safe_emalloc(alloc_len, sizeof(char), 0);
                                        memcpy(new_buf, result, *result_len);
                                        efree(result);
                                        result = new_buf;
                                }
                                /* stick that last bit of string on our output */
                                memcpy(&result[*result_len], piece, subject_len - start_offset);
                                *result_len += subject_len - start_offset;
                                result[*result_len] = '\0';
                                break;
                        }
                } else {
                        pcre_handle_exec_error(count TSRMLS_CC);
                        efree(result);
                        result = NULL;
                        break;
                }
                        
                /* If we have matched an empty string, mimic what Perl's /g options does.
                   This turns out to be rather cunning. First we set PCRE_NOTEMPTY and try
                   the match again at the same point. If this fails (picked up above) we
                   advance to the next character. */
                g_notempty = (offsets[1] == offsets[0])? PCRE_NOTEMPTY | PCRE_ANCHORED : 0;
                
                /* Advance to the next piece. */
                start_offset = offsets[1];
        }
        
        efree(offsets);

        return result;
}
/* }}} */

/* {{{ php_replace_in_subject
 */
static char *php_replace_in_subject(zval *regex, zval *replace, zval **subject, int *result_len, int limit, zend_bool is_callable_replace, int *replace_count TSRMLS_DC)
{
        zval            **regex_entry,
                                **replace_entry = NULL,
                                 *replace_value,
                                  empty_replace;
        char            *subject_value,
                                *result;
        int                      subject_len;

        /* Make sure we're dealing with strings. */     
        convert_to_string_ex(subject);
        /* FIXME: This might need to be changed to STR_EMPTY_ALLOC(). Check if this zval could be dtor()'ed somehow */
        ZVAL_STRINGL(&empty_replace, "", 0, 0);
        
        /* If regex is an array */
        if (Z_TYPE_P(regex) == IS_ARRAY) {
                /* Duplicate subject string for repeated replacement */
                subject_value = estrndup(Z_STRVAL_PP(subject), Z_STRLEN_PP(subject));
                subject_len = Z_STRLEN_PP(subject);
                *result_len = subject_len;
                
                zend_hash_internal_pointer_reset(Z_ARRVAL_P(regex));

                replace_value = replace;
                if (Z_TYPE_P(replace) == IS_ARRAY && !is_callable_replace)
                        zend_hash_internal_pointer_reset(Z_ARRVAL_P(replace));

                /* For each entry in the regex array, get the entry */
                while (zend_hash_get_current_data(Z_ARRVAL_P(regex), (void **)&regex_entry) == SUCCESS) {
                        /* Make sure we're dealing with strings. */     
                        convert_to_string_ex(regex_entry);
                
                        /* If replace is an array and not a callable construct */
                        if (Z_TYPE_P(replace) == IS_ARRAY && !is_callable_replace) {
                                /* Get current entry */
                                if (zend_hash_get_current_data(Z_ARRVAL_P(replace), (void **)&replace_entry) == SUCCESS) {
                                        if (!is_callable_replace) {
                                                convert_to_string_ex(replace_entry);
                                        }
                                        replace_value = *replace_entry;
                                        zend_hash_move_forward(Z_ARRVAL_P(replace));
                                } else {
                                        /* We've run out of replacement strings, so use an empty one */
                                        replace_value = &empty_replace;
                                }
                        }
                        
                        /* Do the actual replacement and put the result back into subject_value
                           for further replacements. */
                        if ((result = php_pcre_replace(Z_STRVAL_PP(regex_entry),
                                                                                   Z_STRLEN_PP(regex_entry),
                                                                                   subject_value,
                                                                                   subject_len,
                                                                                   replace_value,
                                                                                   is_callable_replace,
                                                                                   result_len,
                                                                                   limit,
                                                                                   replace_count TSRMLS_CC)) != NULL) {
                                efree(subject_value);
                                subject_value = result;
                                subject_len = *result_len;
                        } else {
                                efree(subject_value);
                                return NULL;
                        }

                        zend_hash_move_forward(Z_ARRVAL_P(regex));
                }

                return subject_value;
        } else {
                result = php_pcre_replace(Z_STRVAL_P(regex),
                                                                  Z_STRLEN_P(regex),
                                                                  Z_STRVAL_PP(subject),
                                                                  Z_STRLEN_PP(subject),
                                                                  replace,
                                                                  is_callable_replace,
                                                                  result_len,
                                                                  limit,
                                                                  replace_count TSRMLS_CC);
                return result;
        }
}
/* }}} */

/* {{{ preg_replace_impl
 */
static void preg_replace_impl(INTERNAL_FUNCTION_PARAMETERS, zend_bool is_callable_replace)
{
        zval               **regex,
                                   **replace,
                                   **subject,
                                   **limit,
                                   **subject_entry,
                                   **zcount;
        char                    *result;
        int                              result_len;
        int                              limit_val = -1;
        char                    *string_key;
        ulong                    num_key;
        char                    *callback_name;
        int                              replace_count=0;
        int                             *replace_count_ptr=NULL; 
        
        /* Get function parameters and do error-checking. */
        if (ZEND_NUM_ARGS() < 3 || ZEND_NUM_ARGS() > 5 ||
                zend_get_parameters_ex(ZEND_NUM_ARGS(), &regex, &replace, &subject, &limit, &zcount) == FAILURE) {
                WRONG_PARAM_COUNT;
        }
        if (!is_callable_replace && Z_TYPE_PP(replace) == IS_ARRAY && Z_TYPE_PP(regex) != IS_ARRAY) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Parameter mismatch, pattern is a string while replacement is an array");
                RETURN_FALSE;
        }

        SEPARATE_ZVAL(replace);
        if (Z_TYPE_PP(replace) != IS_ARRAY)
                convert_to_string_ex(replace);
        if (is_callable_replace) {
                if (!zend_is_callable(*replace, 0, &callback_name)) {
                        php_error_docref(NULL TSRMLS_CC, E_WARNING, "Requires argument 2, '%s', to be a valid callback", callback_name);
                        efree(callback_name);
                        *return_value = **subject;
                        zval_copy_ctor(return_value);
                        INIT_PZVAL(return_value);
                        return;
                }
                efree(callback_name);
        }

        SEPARATE_ZVAL(regex);
        SEPARATE_ZVAL(subject);

        if (ZEND_NUM_ARGS() > 3) {
                convert_to_long_ex(limit);
                limit_val = Z_LVAL_PP(limit);
        }
        if (ZEND_NUM_ARGS() > 4) {
                replace_count_ptr =& replace_count;
        }
                
        if (Z_TYPE_PP(regex) != IS_ARRAY)
                convert_to_string_ex(regex);
        
        /* if subject is an array */
        if (Z_TYPE_PP(subject) == IS_ARRAY) {
                array_init(return_value);
                zend_hash_internal_pointer_reset(Z_ARRVAL_PP(subject));

                /* For each subject entry, convert it to string, then perform replacement
                   and add the result to the return_value array. */
                while (zend_hash_get_current_data(Z_ARRVAL_PP(subject), (void **)&subject_entry) == SUCCESS) {
                        SEPARATE_ZVAL(subject_entry);
                        if ((result = php_replace_in_subject(*regex, *replace, subject_entry, &result_len, limit_val, is_callable_replace, replace_count_ptr TSRMLS_CC)) != NULL) {
                                /* Add to return array */
                                switch(zend_hash_get_current_key(Z_ARRVAL_PP(subject), &string_key, &num_key, 0))
                                {
                                        case HASH_KEY_IS_STRING:
                                                add_assoc_stringl(return_value, string_key, result, result_len, 0);
                                                break;

                                        case HASH_KEY_IS_LONG:
                                                add_index_stringl(return_value, num_key, result, result_len, 0);
                                                break;
                                }
                        }
                
                        zend_hash_move_forward(Z_ARRVAL_PP(subject));
                }
        } else {        /* if subject is not an array */
                if ((result = php_replace_in_subject(*regex, *replace, subject, &result_len, limit_val, is_callable_replace, replace_count_ptr TSRMLS_CC)) != NULL) {
                        RETVAL_STRINGL(result, result_len, 0);
                }
        }
        if (replace_count_ptr) {
                zval_dtor(*zcount);
                ZVAL_LONG(*zcount, replace_count);
        }
        
}
/* }}} */

/* {{{ proto string preg_replace(mixed regex, mixed replace, mixed subject [, int limit [, count]])
   Perform Perl-style regular expression replacement. */
PHP_FUNCTION(preg_replace)
{
        preg_replace_impl(INTERNAL_FUNCTION_PARAM_PASSTHRU, 0);
}
/* }}} */

/* {{{ proto string preg_replace_callback(mixed regex, mixed callback, mixed subject [, int limit [, count]])
   Perform Perl-style regular expression replacement using replacement callback. */
PHP_FUNCTION(preg_replace_callback)
{
        preg_replace_impl(INTERNAL_FUNCTION_PARAM_PASSTHRU, 1);
}
/* }}} */

/* {{{ proto array preg_split(string pattern, string subject [, int limit [, int flags]]) 
   Split string into an array using a perl-style regular expression as a delimiter */
PHP_FUNCTION(preg_split)
{
        char                            *regex;                 /* Regular expression */
        char                            *subject;               /* String to match against */
        int                                      regex_len;
        int                                      subject_len;
        long                             limit_val = -1;/* Integer value of limit */
        long                             flags = 0;             /* Match control flags */
        pcre_cache_entry        *pce;                   /* Compiled regular expression */

        /* Get function parameters and do error checking */     
        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "ss|ll", &regex, &regex_len,
                                                          &subject, &subject_len, &limit_val, &flags) == FAILURE) {
                RETURN_FALSE;
        }
        
        /* Compile regex or get it from cache. */
        if ((pce = pcre_get_compiled_regex_cache(regex, regex_len TSRMLS_CC)) == NULL) {
                RETURN_FALSE;
        }

        php_pcre_split_impl(pce, subject, subject_len, return_value, limit_val, flags TSRMLS_CC);
}
/* }}} */

/* {{{ php_pcre_split
 */
PHPAPI void php_pcre_split_impl(pcre_cache_entry *pce, char *subject, int subject_len, zval *return_value,
        long limit_val, long flags TSRMLS_DC)
{
        pcre_extra              *extra = NULL;          /* Holds results of studying */
        pcre                    *re_bump = NULL;        /* Regex instance for empty matches */
        pcre_extra              *extra_bump = NULL;     /* Almost dummy */
        pcre_extra               extra_data;            /* Used locally for exec options */
        int                             *offsets;                       /* Array of subpattern offsets */
        int                              size_offsets;          /* Size of the offsets array */
        int                              exoptions = 0;         /* Execution options */
        int                              count = 0;                     /* Count of matched subpatterns */
        int                              start_offset;          /* Where the new search starts */
        int                              next_offset;           /* End of the last delimiter match + 1 */
        int                              g_notempty = 0;        /* If the match should not be empty */
        char                    *match,                         /* The current match */
                                        *last_match;            /* Location of last match */
        int                              rc;
        int                              no_empty;                      /* If NO_EMPTY flag is set */
        int                              delim_capture;         /* If delimiters should be captured */
        int                              offset_capture;        /* If offsets should be captured */

        no_empty = flags & PREG_SPLIT_NO_EMPTY;
        delim_capture = flags & PREG_SPLIT_DELIM_CAPTURE;
        offset_capture = flags & PREG_SPLIT_OFFSET_CAPTURE;
        
        if (limit_val == 0) {
                limit_val = -1;
        }

        if (extra == NULL) {
                extra_data.flags = PCRE_EXTRA_MATCH_LIMIT | PCRE_EXTRA_MATCH_LIMIT_RECURSION;
                extra = &extra_data;
        }
        extra->match_limit = PCRE_G(backtrack_limit);
        extra->match_limit_recursion = PCRE_G(recursion_limit);
        
        /* Initialize return value */
        array_init(return_value);

        /* Calculate the size of the offsets array, and allocate memory for it. */
        rc = pcre_fullinfo(pce->re, extra, PCRE_INFO_CAPTURECOUNT, &size_offsets);
        if (rc < 0) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Internal pcre_fullinfo() error %d", rc);
                RETURN_FALSE;
        }
        size_offsets = (size_offsets + 1) * 3;
        offsets = (int *)safe_emalloc(size_offsets, sizeof(int), 0);
        
        /* Start at the beginning of the string */
        start_offset = 0;
        next_offset = 0;
        last_match = subject;
        match = NULL;
        PCRE_G(error_code) = PHP_PCRE_NO_ERROR;
        
        /* Get next piece if no limit or limit not yet reached and something matched*/
        while ((limit_val == -1 || limit_val > 1)) {
                count = pcre_exec(pce->re, extra, subject,
                                                  subject_len, start_offset,
                                                  exoptions|g_notempty, offsets, size_offsets);

                /* Check for too many substrings condition. */
                if (count == 0) {
                        php_error_docref(NULL TSRMLS_CC,E_NOTICE, "Matched, but too many substrings");
                        count = size_offsets/3;
                }
                                
                /* If something matched */
                if (count > 0) {
                        match = subject + offsets[0];

                        if (!no_empty || &subject[offsets[0]] != last_match) {

                                if (offset_capture) {
                                        /* Add (match, offset) pair to the return value */
                                        add_offset_pair(return_value, last_match, &subject[offsets[0]]-last_match, next_offset, NULL);
                                } else {
                                        /* Add the piece to the return value */
                                        add_next_index_stringl(return_value, last_match,
                                                                           &subject[offsets[0]]-last_match, 1);
                                }

                                /* One less left to do */
                                if (limit_val != -1)
                                        limit_val--;
                        }
                        
                        last_match = &subject[offsets[1]];
                        next_offset = offsets[1];

                        if (delim_capture) {
                                int i, match_len;
                                for (i = 1; i < count; i++) {
                                        match_len = offsets[(i<<1)+1] - offsets[i<<1];
                                        /* If we have matched a delimiter */
                                        if (!no_empty || match_len > 0) {
                                                if (offset_capture) {
                                                        add_offset_pair(return_value, &subject[offsets[i<<1]], match_len, offsets[i<<1], NULL);
                                                } else {
                                                        add_next_index_stringl(return_value,
                                                                                                   &subject[offsets[i<<1]],
                                                                                                   match_len, 1);
                                                }
                                        }
                                }
                        }
                } else if (count == PCRE_ERROR_NOMATCH) {
                        /* If we previously set PCRE_NOTEMPTY after a null match,
                           this is not necessarily the end. We need to advance
                           the start offset, and continue. Fudge the offset values
                           to achieve this, unless we're already at the end of the string. */
                        if (g_notempty != 0 && start_offset < subject_len) {
                                if (pce->compile_options & PCRE_UTF8) {
                                        if (re_bump == NULL) {
                                                int dummy;

                                                if ((re_bump = pcre_get_compiled_regex("/./u", &extra_bump, &dummy TSRMLS_CC)) == NULL) {
                                                        RETURN_FALSE;
                                                }
                                        }
                                        count = pcre_exec(re_bump, extra_bump, subject,
                                                          subject_len, start_offset,
                                                          exoptions, offsets, size_offsets);
                                        if (count < 1) {
                                                php_error_docref(NULL TSRMLS_CC,E_NOTICE, "Unknown error");
                                                offsets[0] = start_offset;
                                                offsets[1] = start_offset + 1;
                                        }
                                } else {
                                        offsets[0] = start_offset;
                                        offsets[1] = start_offset + 1;
                                }
                        } else
                                break;
                } else {
                        pcre_handle_exec_error(count TSRMLS_CC);
                        break;
                }

                /* If we have matched an empty string, mimic what Perl's /g options does.
                   This turns out to be rather cunning. First we set PCRE_NOTEMPTY and try
                   the match again at the same point. If this fails (picked up above) we
                   advance to the next character. */
                g_notempty = (offsets[1] == offsets[0])? PCRE_NOTEMPTY | PCRE_ANCHORED : 0;
                
                /* Advance to the position right after the last full match */
                start_offset = offsets[1];
        }


        start_offset = last_match - subject; /* the offset might have been incremented, but without further successful matches */

        if (!no_empty || start_offset < subject_len)
        {
                if (offset_capture) {
                        /* Add the last (match, offset) pair to the return value */
                        add_offset_pair(return_value, &subject[start_offset], subject_len - start_offset, start_offset, NULL);
                } else {
                        /* Add the last piece to the return value */
                        add_next_index_stringl(return_value, last_match, subject + subject_len - last_match, 1);
                }
        }

        
        /* Clean up */
        efree(offsets);
}
/* }}} */

/* {{{ proto string preg_quote(string str [, string delim_char])
   Quote regular expression characters plus an optional character */
PHP_FUNCTION(preg_quote)
{
        int              in_str_len;
        char    *in_str;                /* Input string argument */
        char    *in_str_end;    /* End of the input string */
        int              delim_len;
        char    *delim = NULL;  /* Additional delimiter argument */
        char    *out_str,               /* Output string with quoted characters */
                        *p,                             /* Iterator for input string */
                        *q,                             /* Iterator for output string */
                         delim_char=0,  /* Delimiter character to be quoted */
                         c;                             /* Current character */
        zend_bool quote_delim = 0; /* Whether to quote additional delim char */
        
        /* Get the arguments and check for errors */
        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s|s", &in_str, &in_str_len,
                                                          &delim, &delim_len) == FAILURE) {
                return;
        }
        
        in_str_end = in_str + in_str_len;

        /* Nothing to do if we got an empty string */
        if (in_str == in_str_end) {
                RETURN_EMPTY_STRING();
        }

        if (delim && *delim) {
                delim_char = delim[0];
                quote_delim = 1;
        }
        
        /* Allocate enough memory so that even if each character
           is quoted, we won't run out of room */
        out_str = safe_emalloc(4, in_str_len, 1);
        
        /* Go through the string and quote necessary characters */
        for(p = in_str, q = out_str; p != in_str_end; p++) {
                c = *p;
                switch(c) {
                        case '.':
                        case '\\':
                        case '+':
                        case '*':
                        case '?':
                        case '[':
                        case '^':
                        case ']':
                        case '$':
                        case '(':
                        case ')':
                        case '{':
                        case '}':
                        case '=':
                        case '!':
                        case '>':
                        case '<':
                        case '|':
                        case ':':
                                *q++ = '\\';
                                *q++ = c;
                                break;

                        case '\0':
                                *q++ = '\\';
                                *q++ = '0';
                                *q++ = '0';
                                *q++ = '0';
                                break;

                        default:
                                if (quote_delim && c == delim_char)
                                        *q++ = '\\';
                                *q++ = c;
                                break;
                }
        }
        *q = '\0';
        
        /* Reallocate string and return it */
        RETVAL_STRINGL(erealloc(out_str, q - out_str + 1), q - out_str, 0);
}
/* }}} */

/* {{{ proto array preg_grep(string regex, array input [, int flags])
   Searches array and returns entries which match regex */
PHP_FUNCTION(preg_grep)
{
        char                            *regex;                 /* Regular expression */
        int                                      regex_len;
        zval                            *input;                 /* Input array */
        long                             flags = 0;             /* Match control flags */
        pcre_cache_entry        *pce;                   /* Compiled regular expression */

        /* Get arguments and do error checking */
        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "sa|l", &regex, &regex_len,
                                                          &input, &flags) == FAILURE) {
                return;
        }
        
        /* Compile regex or get it from cache. */
        if ((pce = pcre_get_compiled_regex_cache(regex, regex_len TSRMLS_CC)) == NULL) {
                RETURN_FALSE;
        }
        
        php_pcre_grep_impl(pce, input, return_value, flags TSRMLS_CC);
}
/* }}} */

PHPAPI void  php_pcre_grep_impl(pcre_cache_entry *pce, zval *input, zval *return_value, long flags TSRMLS_DC) /* {{{ */
{
        zval               **entry;                             /* An entry in the input array */
        pcre_extra              *extra = pce->extra;/* Holds results of studying */
        pcre_extra               extra_data;            /* Used locally for exec options */
        int                             *offsets;                       /* Array of subpattern offsets */
        int                              size_offsets;          /* Size of the offsets array */
        int                              count = 0;                     /* Count of matched subpatterns */
        char                    *string_key;
        ulong                    num_key;
        zend_bool                invert;                        /* Whether to return non-matching
                                                                                   entries */
        int                              rc;
        
        invert = flags & PREG_GREP_INVERT ? 1 : 0;
        
        if (extra == NULL) {
                extra_data.flags = PCRE_EXTRA_MATCH_LIMIT | PCRE_EXTRA_MATCH_LIMIT_RECURSION;
                extra = &extra_data;
        }
        extra->match_limit = PCRE_G(backtrack_limit);
        extra->match_limit_recursion = PCRE_G(recursion_limit);

        /* Calculate the size of the offsets array, and allocate memory for it. */
        rc = pcre_fullinfo(pce->re, extra, PCRE_INFO_CAPTURECOUNT, &size_offsets);
        if (rc < 0) {
                php_error_docref(NULL TSRMLS_CC, E_WARNING, "Internal pcre_fullinfo() error %d", rc);
                RETURN_FALSE;
        }
        size_offsets = (size_offsets + 1) * 3;
        offsets = (int *)safe_emalloc(size_offsets, sizeof(int), 0);
        
        /* Initialize return array */
        array_init(return_value);

        PCRE_G(error_code) = PHP_PCRE_NO_ERROR;

        /* Go through the input array */
        zend_hash_internal_pointer_reset(Z_ARRVAL_P(input));
        while(zend_hash_get_current_data(Z_ARRVAL_P(input), (void **)&entry) == SUCCESS) {

                convert_to_string_ex(entry);

                /* Perform the match */
                count = pcre_exec(pce->re, extra, Z_STRVAL_PP(entry),
                                                  Z_STRLEN_PP(entry), 0,
                                                  0, offsets, size_offsets);

                /* Check for too many substrings condition. */
                if (count == 0) {
                        php_error_docref(NULL TSRMLS_CC, E_NOTICE, "Matched, but too many substrings");
                        count = size_offsets/3;
                } else if (count < 0 && count != PCRE_ERROR_NOMATCH) {
                        pcre_handle_exec_error(count TSRMLS_CC);
                        break;
                }

                /* If the entry fits our requirements */
                if ((count > 0 && !invert) ||
                        (count == PCRE_ERROR_NOMATCH && invert)) {
                        (*entry)->refcount++;

                        /* Add to return array */
                        switch (zend_hash_get_current_key(Z_ARRVAL_P(input), &string_key, &num_key, 0))
                        {
                                case HASH_KEY_IS_STRING:
                                        zend_hash_update(Z_ARRVAL_P(return_value), string_key,
                                                                         strlen(string_key)+1, entry, sizeof(zval *), NULL);
                                        break;

                                case HASH_KEY_IS_LONG:
                                        zend_hash_index_update(Z_ARRVAL_P(return_value), num_key, entry,
                                                                                   sizeof(zval *), NULL);
                                        break;
                        }
                }
                
                zend_hash_move_forward(Z_ARRVAL_P(input));
        }
        zend_hash_internal_pointer_reset(Z_ARRVAL_P(input));
        /* Clean up */
        efree(offsets);
}
/* }}} */

/* {{{ proto int preg_last_error()
   Returns the error code of the last regexp execution. */
PHP_FUNCTION(preg_last_error)
{
        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "") == FAILURE) {
                return;
        }

        RETURN_LONG(PCRE_G(error_code));
}
/* }}} */

/* {{{ module definition structures */

zend_function_entry pcre_functions[] = {
        PHP_FE(preg_match,                              third_arg_force_ref)
        PHP_FE(preg_match_all,                  third_arg_force_ref)
        PHP_FE(preg_replace,                    fifth_arg_force_ref)
        PHP_FE(preg_replace_callback,   fifth_arg_force_ref)
        PHP_FE(preg_split,                              NULL)
        PHP_FE(preg_quote,                              NULL)
        PHP_FE(preg_grep,                               NULL)
        PHP_FE(preg_last_error,                 NULL)
        {NULL,          NULL,                           NULL}
};

zend_module_entry pcre_module_entry = {
        STANDARD_MODULE_HEADER,
   "pcre",
        pcre_functions,
        PHP_MINIT(pcre),
        PHP_MSHUTDOWN(pcre),
        NULL,
        NULL,
        PHP_MINFO(pcre),
        NO_VERSION_YET,
        PHP_MODULE_GLOBALS(pcre),
        PHP_GINIT(pcre),
        PHP_GSHUTDOWN(pcre),
        NULL,
        STANDARD_MODULE_PROPERTIES_EX
};

#ifdef COMPILE_DL_PCRE
ZEND_GET_MODULE(pcre)
# ifdef PHP_WIN32
# include "zend_arg_defs.c"
# endif
#endif

/* }}} */

#endif /* HAVE_PCRE || HAVE_BUNDLED_PCRE */

/*
 * Local variables:
 * tab-width: 4
 * c-basic-offset: 4
 * End:
 * vim600: sw=4 ts=4 fdm=marker
 * vim<600: sw=4 ts=4
 */

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