root/ext/intl/grapheme/grapheme_string.c

/* [<][>][^][v][top][bottom][index][help] */

DEFINITIONS

This source file includes following definitions.
  1. grapheme_register_constants
  2. PHP_FUNCTION
  3. PHP_FUNCTION
  4. PHP_FUNCTION
  5. PHP_FUNCTION
  6. PHP_FUNCTION
  7. PHP_FUNCTION
  8. strstr_common_handler
  9. PHP_FUNCTION
  10. PHP_FUNCTION
  11. grapheme_extract_charcount_iter
  12. grapheme_extract_bytecount_iter
  13. grapheme_extract_count_iter
  14. PHP_FUNCTION

/*
   +----------------------------------------------------------------------+
   | PHP Version 5                                                                                                                |
   +----------------------------------------------------------------------+
   | 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: Ed Batutis <ed@batutis.com>                                                                  |
   +----------------------------------------------------------------------+
 */

/* {{{ includes */
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <php.h>
#include "grapheme.h"
#include "grapheme_util.h"

#include <unicode/utypes.h>
#include <unicode/ucol.h>
#include <unicode/ustring.h>
#include <unicode/ubrk.h>

#include "ext/standard/php_string.h"

/* }}} */

#define GRAPHEME_EXTRACT_TYPE_COUNT             0
#define GRAPHEME_EXTRACT_TYPE_MAXBYTES  1
#define GRAPHEME_EXTRACT_TYPE_MAXCHARS  2
#define GRAPHEME_EXTRACT_TYPE_MIN       GRAPHEME_EXTRACT_TYPE_COUNT
#define GRAPHEME_EXTRACT_TYPE_MAX       GRAPHEME_EXTRACT_TYPE_MAXCHARS


/* {{{ grapheme_register_constants
 * Register API constants
 */
void grapheme_register_constants( INIT_FUNC_ARGS )
{
        REGISTER_LONG_CONSTANT("GRAPHEME_EXTR_COUNT", GRAPHEME_EXTRACT_TYPE_COUNT, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("GRAPHEME_EXTR_MAXBYTES", GRAPHEME_EXTRACT_TYPE_MAXBYTES, CONST_CS | CONST_PERSISTENT);
        REGISTER_LONG_CONSTANT("GRAPHEME_EXTR_MAXCHARS", GRAPHEME_EXTRACT_TYPE_MAXCHARS, CONST_CS | CONST_PERSISTENT);
}
/* }}} */

/* {{{ proto int grapheme_strlen(string str)
   Get number of graphemes in a string */
PHP_FUNCTION(grapheme_strlen)
{
        unsigned char* string;
        int string_len;
        UChar* ustring = NULL;
        int ustring_len = 0;
        int ret_len;
        UErrorCode status;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", (char **)&string, &string_len) == FAILURE) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_strlen: unable to parse input param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        ret_len = grapheme_ascii_check(string, string_len);

        if ( ret_len >= 0 )
                RETURN_LONG(ret_len);

        /* convert the string to UTF-16. */
        status = U_ZERO_ERROR;
        intl_convert_utf8_to_utf16(&ustring, &ustring_len, (char*) string, string_len, &status );

        if ( U_FAILURE( status ) ) {
                /* Set global error code. */
                intl_error_set_code( NULL, status TSRMLS_CC );

                /* Set error messages. */
                intl_error_set_custom_msg( NULL, "Error converting input string to UTF-16", 0 TSRMLS_CC );
                if (ustring) {
                        efree( ustring );
                }
                RETURN_NULL();
        }

        ret_len = grapheme_split_string(ustring, ustring_len, NULL, 0 TSRMLS_CC );

        if (ustring) {
                efree( ustring );
        }

        if (ret_len >= 0) {
                RETVAL_LONG(ret_len);
        } else {
                RETVAL_FALSE;
        }
}
/* }}} */

/* {{{ proto int grapheme_strpos(string haystack, string needle [, int offset ])
   Find position of first occurrence of a string within another */
PHP_FUNCTION(grapheme_strpos)
{
        unsigned char *haystack, *needle;
        int haystack_len, needle_len;
        unsigned char *found;
        long loffset = 0;
        int32_t offset = 0;
        int ret_pos;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "ss|l", (char **)&haystack, &haystack_len, (char **)&needle, &needle_len, &loffset) == FAILURE) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_strpos: unable to parse input param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        if ( OUTSIDE_STRING(loffset, haystack_len) ) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_strpos: Offset not contained in string", 1 TSRMLS_CC );

                RETURN_FALSE;
        }

        /* we checked that it will fit: */
        offset = (int32_t) loffset;

        /* the offset is 'grapheme count offset' so it still might be invalid - we'll check it later */

        if (needle_len == 0) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_strpos: Empty delimiter", 1 TSRMLS_CC );

                RETURN_FALSE;
        }


        /* quick check to see if the string might be there
         * I realize that 'offset' is 'grapheme count offset' but will work in spite of that
        */
        found = (unsigned char *)php_memnstr((char *)haystack + offset, (char *)needle, needle_len, (char *)haystack + haystack_len);

        /* if it isn't there the we are done */
        if (!found) {
                RETURN_FALSE;
        }

        /* if it is there, and if the haystack is ascii, we are all done */
        if ( grapheme_ascii_check(haystack, haystack_len) >= 0 ) {

                RETURN_LONG(found - haystack);
        }

        /* do utf16 part of the strpos */
        ret_pos = grapheme_strpos_utf16(haystack, haystack_len, needle, needle_len, offset, NULL, 0 /* fIgnoreCase */, 0 /* last */ TSRMLS_CC );

        if ( ret_pos >= 0 ) {
                RETURN_LONG(ret_pos);
        } else {
                RETURN_FALSE;
        }

}
/* }}} */

/* {{{ proto int grapheme_stripos(string haystack, string needle [, int offset ])
   Find position of first occurrence of a string within another, ignoring case differences */
PHP_FUNCTION(grapheme_stripos)
{
        unsigned char *haystack, *needle, *haystack_dup, *needle_dup;
        int haystack_len, needle_len;
        unsigned char *found;
        long loffset = 0;
        int32_t offset = 0;
        int ret_pos;
        int is_ascii;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "ss|l", (char **)&haystack, &haystack_len, (char **)&needle, &needle_len, &loffset) == FAILURE) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_stripos: unable to parse input param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        if ( OUTSIDE_STRING(loffset, haystack_len) ) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_stripos: Offset not contained in string", 1 TSRMLS_CC );

                RETURN_FALSE;
        }

        /* we checked that it will fit: */
        offset = (int32_t) loffset;

        /* the offset is 'grapheme count offset' so it still might be invalid - we'll check it later */

        if (needle_len == 0) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_stripos: Empty delimiter", 1 TSRMLS_CC );

                RETURN_FALSE;
        }


        is_ascii = ( grapheme_ascii_check(haystack, haystack_len) >= 0 );

        if ( is_ascii ) {
                needle_dup = (unsigned char *)estrndup((char *)needle, needle_len);
                php_strtolower((char *)needle_dup, needle_len);
                haystack_dup = (unsigned char *)estrndup((char *)haystack, haystack_len);
                php_strtolower((char *)haystack_dup, haystack_len);

                found = (unsigned char*) php_memnstr((char *)haystack_dup + offset, (char *)needle_dup, needle_len, (char *)haystack_dup + haystack_len);

                efree(haystack_dup);
                efree(needle_dup);

                if (found) {
                        RETURN_LONG(found - haystack_dup);
                }

                /* if needle was ascii too, we are all done, otherwise we need to try using Unicode to see what we get */
                if ( grapheme_ascii_check(needle, needle_len) >= 0 ) {
                        RETURN_FALSE;
                }
        }

        /* do utf16 part of the strpos */
        ret_pos = grapheme_strpos_utf16(haystack, haystack_len, needle, needle_len, offset, NULL, 1 /* fIgnoreCase */, 0 /*last */ TSRMLS_CC );

        if ( ret_pos >= 0 ) {
                RETURN_LONG(ret_pos);
        } else {
                RETURN_FALSE;
        }

}
/* }}} */

/* {{{ proto int grapheme_strrpos(string haystack, string needle [, int offset])
   Find position of last occurrence of a string within another */
PHP_FUNCTION(grapheme_strrpos)
{
        unsigned char *haystack, *needle;
        int haystack_len, needle_len;
        long loffset = 0;
        int32_t offset = 0;
        int32_t ret_pos;
        int is_ascii;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "ss|l", (char **)&haystack, &haystack_len, (char **)&needle, &needle_len, &loffset) == FAILURE) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_strrpos: unable to parse input param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        if ( OUTSIDE_STRING(loffset, haystack_len) ) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_strpos: Offset not contained in string", 1 TSRMLS_CC );

                RETURN_FALSE;
        }

        /* we checked that it will fit: */
        offset = (int32_t) loffset;

        /* the offset is 'grapheme count offset' so it still might be invalid - we'll check it later */

        if (needle_len == 0) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_strpos: Empty delimiter", 1 TSRMLS_CC );

                RETURN_FALSE;
        }

        is_ascii = grapheme_ascii_check(haystack, haystack_len) >= 0;

        if ( is_ascii ) {

                ret_pos = grapheme_strrpos_ascii(haystack, haystack_len, needle, needle_len, offset);


                if ( ret_pos >= 0 ) {
                        RETURN_LONG(ret_pos);
                }

                /* if the needle was ascii too, we are done */

                if (  grapheme_ascii_check(needle, needle_len) >= 0 ) {
                        RETURN_FALSE;
                }

                /* else we need to continue via utf16 */
        }

        ret_pos = grapheme_strpos_utf16(haystack, haystack_len, needle, needle_len, offset, NULL, 0 /* f_ignore_case */, 1/* last */ TSRMLS_CC);

        if ( ret_pos >= 0 ) {
                RETURN_LONG(ret_pos);
        } else {
                RETURN_FALSE;
        }


}
/* }}} */

/* {{{ proto int grapheme_strripos(string haystack, string needle [, int offset])
   Find position of last occurrence of a string within another, ignoring case */
PHP_FUNCTION(grapheme_strripos)
{
        unsigned char *haystack, *needle;
        int haystack_len, needle_len;
        long loffset = 0;
        int32_t offset = 0;
        int32_t ret_pos;
        int is_ascii;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "ss|l", (char **)&haystack, &haystack_len, (char **)&needle, &needle_len, &loffset) == FAILURE) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_strrpos: unable to parse input param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        if ( OUTSIDE_STRING(loffset, haystack_len) ) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_strpos: Offset not contained in string", 1 TSRMLS_CC );

                RETURN_FALSE;
        }

        /* we checked that it will fit: */
        offset = (int32_t) loffset;

        /* the offset is 'grapheme count offset' so it still might be invalid - we'll check it later */

        if (needle_len == 0) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_strpos: Empty delimiter", 1 TSRMLS_CC );

                RETURN_FALSE;
        }

        is_ascii = grapheme_ascii_check(haystack, haystack_len) >= 0;

        if ( is_ascii ) {
                unsigned char *needle_dup, *haystack_dup;

                needle_dup = (unsigned char *)estrndup((char *)needle, needle_len);
                php_strtolower((char *)needle_dup, needle_len);
                haystack_dup = (unsigned char *)estrndup((char *)haystack, haystack_len);
                php_strtolower((char *)haystack_dup, haystack_len);

                ret_pos = grapheme_strrpos_ascii(haystack_dup, haystack_len, needle_dup, needle_len, offset);

                efree(haystack_dup);
                efree(needle_dup);

                if ( ret_pos >= 0 ) {
                        RETURN_LONG(ret_pos);
                }

                /* if the needle was ascii too, we are done */

                if (  grapheme_ascii_check(needle, needle_len) >= 0 ) {
                        RETURN_FALSE;
                }

                /* else we need to continue via utf16 */
        }

        ret_pos = grapheme_strpos_utf16(haystack, haystack_len, needle, needle_len, offset, NULL,  1 /* f_ignore_case */, 1 /*last */ TSRMLS_CC);

        if ( ret_pos >= 0 ) {
                RETURN_LONG(ret_pos);
        } else {
                RETURN_FALSE;
        }


}
/* }}} */

/* {{{ proto string grapheme_substr(string str, int start [, int length])
   Returns part of a string */
PHP_FUNCTION(grapheme_substr)
{
        unsigned char *str, *sub_str;
        UChar *ustr;
        int str_len, sub_str_len, ustr_len;
        long lstart = 0, length = 0;
        int32_t start = 0;
        int iter_val;
        UErrorCode status;
        unsigned char u_break_iterator_buffer[U_BRK_SAFECLONE_BUFFERSIZE];
        UBreakIterator* bi = NULL;
        int sub_str_start_pos, sub_str_end_pos;
        int32_t (*iter_func)(UBreakIterator *);

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "sl|l", (char **)&str, &str_len, &lstart, &length) == FAILURE) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_substr: unable to parse input param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        if ( OUTSIDE_STRING(lstart, str_len) ) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_substr: start not contained in string", 1 TSRMLS_CC );

                RETURN_FALSE;
        }

        /* we checked that it will fit: */
        start = (int32_t) lstart;

        /* the offset is 'grapheme count offset' so it still might be invalid - we'll check it later */

        if ( grapheme_ascii_check(str, str_len) >= 0 ) {
                grapheme_substr_ascii((char *)str, str_len, start, length, ZEND_NUM_ARGS(), (char **) &sub_str, &sub_str_len);

                if ( NULL == sub_str ) {
                        intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_substr: invalid parameters", 1 TSRMLS_CC );
                        RETURN_FALSE;
                }

                RETURN_STRINGL(((char *)sub_str), sub_str_len, 1);
        }

        ustr = NULL;
        ustr_len = 0;
        status = U_ZERO_ERROR;
        intl_convert_utf8_to_utf16(&ustr, &ustr_len, (char *)str, str_len, &status);

        if ( U_FAILURE( status ) ) {
                /* Set global error code. */
                intl_error_set_code( NULL, status TSRMLS_CC );

                /* Set error messages. */
                intl_error_set_custom_msg( NULL, "Error converting input string to UTF-16", 0 TSRMLS_CC );
                if (ustr) {
                        efree( ustr );
                }
                RETURN_FALSE;
        }

        bi = grapheme_get_break_iterator((void*)u_break_iterator_buffer, &status TSRMLS_CC );

        if( U_FAILURE(status) ) {
                RETURN_FALSE;
        }

        ubrk_setText(bi, ustr, ustr_len,        &status);

        if ( start < 0 ) {
                iter_func = ubrk_previous;
                ubrk_last(bi);
                iter_val = 1;
        }
        else {
                iter_func = ubrk_next;
                iter_val = -1;
        }

        sub_str_start_pos = 0;

        while ( start ) {
                sub_str_start_pos = iter_func(bi);

                if ( UBRK_DONE == sub_str_start_pos ) {
                        break;
                }

                start += iter_val;
        }

        if ( 0 != start || sub_str_start_pos >= ustr_len ) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_substr: start not contained in string", 1 TSRMLS_CC );

                if (ustr) {
                        efree(ustr);
                }
                ubrk_close(bi);
                RETURN_FALSE;
        }

        if (ZEND_NUM_ARGS() <= 2) {

                /* no length supplied, return the rest of the string */

                sub_str = NULL;
                sub_str_len = 0;
                status = U_ZERO_ERROR;
                intl_convert_utf16_to_utf8((char **)&sub_str, &sub_str_len, ustr + sub_str_start_pos, ustr_len - sub_str_start_pos, &status);

                if (ustr) {
                        efree( ustr );
                }
                ubrk_close( bi );

                if ( U_FAILURE( status ) ) {
                        /* Set global error code. */
                        intl_error_set_code( NULL, status TSRMLS_CC );

                        /* Set error messages. */
                        intl_error_set_custom_msg( NULL, "Error converting output string to UTF-8", 0 TSRMLS_CC );

                        if (sub_str) {
                                efree( sub_str );
                        }

                        RETURN_FALSE;
                }

                /* return the allocated string, not a duplicate */
                RETURN_STRINGL(((char *)sub_str), sub_str_len, 0);
        }

        if(length == 0) {
                /* empty length - we've validated start, we can return "" now */
                if (ustr) {
                        efree(ustr);
                }
                ubrk_close(bi);
                RETURN_EMPTY_STRING();          
        }

        /* find the end point of the string to return */

        if ( length < 0 ) {
                iter_func = ubrk_previous;
                ubrk_last(bi);
                iter_val = 1;
        }
        else {
                iter_func = ubrk_next;
                iter_val = -1;
        }

        sub_str_end_pos = 0;

        while ( length ) {
                sub_str_end_pos = iter_func(bi);

                if ( UBRK_DONE == sub_str_end_pos ) {
                        break;
                }

                length += iter_val;
        }

        ubrk_close(bi);

        if ( UBRK_DONE == sub_str_end_pos) {
                if(length < 0) {
                        intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_substr: length not contained in string", 1 TSRMLS_CC );

                        efree(ustr);
                        RETURN_FALSE;
                } else {
                        sub_str_end_pos = ustr_len;
                }
        }
        
        if(sub_str_start_pos > sub_str_end_pos) {
                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_substr: length is beyond start", 1 TSRMLS_CC );

                efree(ustr);
                RETURN_FALSE;
        }

        sub_str = NULL;
        status = U_ZERO_ERROR;
        intl_convert_utf16_to_utf8((char **)&sub_str, &sub_str_len, ustr + sub_str_start_pos, ( sub_str_end_pos - sub_str_start_pos ), &status);

        efree( ustr );

        if ( U_FAILURE( status ) ) {
                /* Set global error code. */
                intl_error_set_code( NULL, status TSRMLS_CC );

                /* Set error messages. */
                intl_error_set_custom_msg( NULL, "Error converting output string to UTF-8", 0 TSRMLS_CC );

                if ( NULL != sub_str )
                        efree( sub_str );

                RETURN_FALSE;
        }

         /* return the allocated string, not a duplicate */
        RETURN_STRINGL(((char *)sub_str), sub_str_len, 0);

}
/* }}} */

/* {{{  strstr_common_handler */
static void strstr_common_handler(INTERNAL_FUNCTION_PARAMETERS, int f_ignore_case)
{
        unsigned char *haystack, *needle, *found;
        int haystack_len, needle_len;
        int ret_pos, uchar_pos;
        zend_bool part = 0;

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "ss|b", (char **)&haystack, &haystack_len, (char **)&needle, &needle_len, &part) == FAILURE) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_strstr: unable to parse input param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        if (needle_len == 0) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_strpos: Empty delimiter", 1 TSRMLS_CC );

                RETURN_FALSE;
        }


        if ( !f_ignore_case ) {

                /* ASCII optimization: quick check to see if the string might be there
                 * I realize that 'offset' is 'grapheme count offset' but will work in spite of that
                */
                found = (unsigned char *)php_memnstr((char *)haystack, (char *)needle, needle_len, (char *)haystack + haystack_len);

                /* if it isn't there the we are done */
                if ( !found ) {
                        RETURN_FALSE;
                }

                /* if it is there, and if the haystack is ascii, we are all done */
                if ( grapheme_ascii_check(haystack, haystack_len) >= 0 ) {
                        size_t found_offset = found - haystack;

                        if (part) {
                                RETURN_STRINGL(((char *)haystack) , found_offset, 1);
                        } else {
                                RETURN_STRINGL(((char *)found), haystack_len - found_offset, 1);
                        }
                }

        }

        /* need to work in utf16 */
        ret_pos = grapheme_strpos_utf16(haystack, haystack_len, needle, needle_len, 0, &uchar_pos, f_ignore_case, 0 /*last */ TSRMLS_CC );

        if ( ret_pos < 0 ) {
                RETURN_FALSE;
        }

        /* uchar_pos is the 'nth' Unicode character position of the needle */

        ret_pos = 0;
        U8_FWD_N(haystack, ret_pos, haystack_len, uchar_pos);

        if (part) {
                RETURN_STRINGL(((char *)haystack), ret_pos, 1);
        }
        else {
                RETURN_STRINGL(((char *)haystack) + ret_pos, haystack_len - ret_pos, 1);
        }

}
/* }}} */

/* {{{ proto string grapheme_strstr(string haystack, string needle[, bool part])
   Finds first occurrence of a string within another */
PHP_FUNCTION(grapheme_strstr)
{
        strstr_common_handler(INTERNAL_FUNCTION_PARAM_PASSTHRU, 0 /* f_ignore_case */);
}
/* }}} */

/* {{{ proto string grapheme_stristr(string haystack, string needle[, bool part])
   Finds first occurrence of a string within another */
PHP_FUNCTION(grapheme_stristr)
{
        strstr_common_handler(INTERNAL_FUNCTION_PARAM_PASSTHRU, 1 /* f_ignore_case */);
}
/* }}} */

/* {{{ grapheme_extract_charcount_iter - grapheme iterator for grapheme_extract MAXCHARS */
static inline int32_t
grapheme_extract_charcount_iter(UBreakIterator *bi, int32_t csize, unsigned char *pstr, int32_t str_len)
{
        int pos = 0, prev_pos = 0;
        int ret_pos = 0, prev_ret_pos = 0;

        while ( 1 ) {
                pos = ubrk_next(bi);

                if ( UBRK_DONE == pos ) {
                        break;
                }

                /* if we are beyond our limit, then the loop is done */
                if ( pos > csize ) {
                        break;
                }

                /* update our pointer in the original UTF-8 buffer by as many characters
                   as ubrk_next iterated over */

                prev_ret_pos = ret_pos;
                U8_FWD_N(pstr, ret_pos, str_len, pos - prev_pos);

                if ( prev_ret_pos == ret_pos ) {
                        /* something wrong - malformed utf8? */
                        break;
                }

                prev_pos = pos;
        }

        return ret_pos;
}
/* }}} */

/* {{{ grapheme_extract_bytecount_iter - grapheme iterator for grapheme_extract MAXBYTES */
static inline int32_t
grapheme_extract_bytecount_iter(UBreakIterator *bi, int32_t bsize, unsigned char *pstr, int32_t str_len)
{
        int pos = 0, prev_pos = 0;
        int ret_pos = 0, prev_ret_pos = 0;

        while ( 1 ) {
                pos = ubrk_next(bi);

                if ( UBRK_DONE == pos ) {
                        break;
                }

                prev_ret_pos = ret_pos;
                U8_FWD_N(pstr, ret_pos, str_len, pos - prev_pos);

                if ( ret_pos > bsize ) {
                        ret_pos = prev_ret_pos;
                        break;
                }

                if ( prev_ret_pos == ret_pos ) {
                        /* something wrong - malformed utf8? */
                        break;
                }

                prev_pos = pos;
        }

        return ret_pos;
}
/* }}} */

/* {{{ grapheme_extract_count_iter - grapheme iterator for grapheme_extract COUNT */
static inline int32_t
grapheme_extract_count_iter(UBreakIterator *bi, int32_t size, unsigned char *pstr, int32_t str_len)
{
        int pos = 0, next_pos = 0;
        int ret_pos = 0;

        while ( size ) {
                next_pos = ubrk_next(bi);

                if ( UBRK_DONE == next_pos ) {
                        break;
                }
                pos = next_pos;
                size--;
        }

        /* pos is one past the last UChar - and represent the number of code units to
                advance in the utf-8 buffer
        */

        U8_FWD_N(pstr, ret_pos, str_len, pos);

        return ret_pos;
}
/* }}} */

/* {{{ grapheme extract iter function pointer array */
typedef int32_t (*grapheme_extract_iter)(UBreakIterator * /*bi*/, int32_t /*size*/, unsigned char * /*pstr*/, int32_t /*str_len*/);

static grapheme_extract_iter grapheme_extract_iters[] = {
        &grapheme_extract_count_iter,
        &grapheme_extract_bytecount_iter,
        &grapheme_extract_charcount_iter,
};
/* }}} */

/* {{{ proto string grapheme_extract(string str, int size[, int extract_type[, int start[, int next]]])
        Function to extract a sequence of default grapheme clusters */
PHP_FUNCTION(grapheme_extract)
{
        unsigned char *str, *pstr;
        UChar *ustr;
        int str_len, ustr_len;
        long size; /* maximum number of grapheme clusters, bytes, or characters (based on extract_type) to return */
        long lstart = 0; /* starting position in str in bytes */
        int32_t start = 0;
        long extract_type = GRAPHEME_EXTRACT_TYPE_COUNT;
        UErrorCode status;
        unsigned char u_break_iterator_buffer[U_BRK_SAFECLONE_BUFFERSIZE];
        UBreakIterator* bi = NULL;
        int ret_pos;
        zval *next = NULL; /* return offset of next part of the string */

        if (zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "sl|llz", (char **)&str, &str_len, &size, &extract_type, &lstart, &next) == FAILURE) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_extract: unable to parse input param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        if ( NULL != next ) {
                if ( !PZVAL_IS_REF(next) ) {
                        intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                                 "grapheme_extract: 'next' was not passed by reference", 0 TSRMLS_CC );

                        RETURN_FALSE;
                }
                else {
                        /* initialize next */
                        zval_dtor(next);
            ZVAL_LONG(next, lstart);
                }
        }

        if ( extract_type < GRAPHEME_EXTRACT_TYPE_MIN || extract_type > GRAPHEME_EXTRACT_TYPE_MAX ) {

                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                         "grapheme_extract: unknown extract type param", 0 TSRMLS_CC );

                RETURN_FALSE;
        }

        if ( lstart > INT32_MAX || lstart < 0 || lstart >= str_len ) {
                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_extract: start not contained in string", 0 TSRMLS_CC );
                RETURN_FALSE;
        }

        if ( size > INT32_MAX || size < 0) {
                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR, "grapheme_extract: size is invalid", 0 TSRMLS_CC );
                RETURN_FALSE;
        }
        if (size == 0) {
                RETURN_EMPTY_STRING();
        }

        /* we checked that it will fit: */
        start = (int32_t) lstart;

        pstr = str + start;

        /* just in case pstr points in the middle of a character, move forward to the start of the next char */
        if ( !UTF8_IS_SINGLE(*pstr) && !U8_IS_LEAD(*pstr) ) {
                unsigned char *str_end = str + str_len;

                while ( !UTF8_IS_SINGLE(*pstr) && !U8_IS_LEAD(*pstr) ) {
                        pstr++;
                        if ( pstr >= str_end ) {
                                intl_error_set( NULL, U_ILLEGAL_ARGUMENT_ERROR,
                                                                "grapheme_extract: invalid input string", 0 TSRMLS_CC );

                                RETURN_FALSE;
                        }
                }
        }

        str_len -= (pstr - str);

        /* if the string is all ASCII up to size+1 - or str_len whichever is first - then we are done.
                (size + 1 because the size-th character might be the beginning of a grapheme cluster)
         */

        if ( -1 != grapheme_ascii_check(pstr, size + 1 < str_len ? size + 1 : str_len ) ) {
        long nsize = ( size < str_len ? size : str_len );
                if ( NULL != next ) {
                        ZVAL_LONG(next, start+nsize);
                }
                RETURN_STRINGL(((char *)pstr), nsize, 1);
        }

        /* convert the strings to UTF-16. */
        ustr = NULL;
        ustr_len = 0;
        status = U_ZERO_ERROR;
        intl_convert_utf8_to_utf16(&ustr, &ustr_len, (char *)pstr, str_len, &status );

        if ( U_FAILURE( status ) ) {
                /* Set global error code. */
                intl_error_set_code( NULL, status TSRMLS_CC );

                /* Set error messages. */
                intl_error_set_custom_msg( NULL, "Error converting input string to UTF-16", 0 TSRMLS_CC );

                if ( NULL != ustr )
                        efree( ustr );

                RETURN_FALSE;
        }

        bi = NULL;
        status = U_ZERO_ERROR;
        bi = grapheme_get_break_iterator(u_break_iterator_buffer, &status TSRMLS_CC );

        ubrk_setText(bi, ustr, ustr_len, &status);

        /* if the caller put us in the middle of a grapheme, we can't detect it in all cases since we
                can't back up. So, we will not do anything. */

        /* now we need to find the end of the chunk the user wants us to return */

        ret_pos = (*grapheme_extract_iters[extract_type])(bi, size, pstr, str_len);

        if (ustr) {
                efree(ustr);
        }
        ubrk_close(bi);

        if ( NULL != next ) {
                ZVAL_LONG(next, start+ret_pos);
        }

        RETURN_STRINGL(((char *)pstr), ret_pos, 1);
}

/* }}} */

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


/* [<][>][^][v][top][bottom][index][help] */