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-rw-r--r--mysql/strings/my_strchr.c111
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+/* Copyright (c) 2005, 2014, Oracle and/or its affiliates. All rights reserved.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation; version 2 of the License.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */
+
+#include <my_global.h>
+#include "m_string.h"
+#include "m_ctype.h"
+
+
+/*
+ Return pointer to first occurrence of character in a multi-byte string
+ or NULL if the character doesn't appear in the multi-byte string or
+ invalid character in charset of multi-byte string is found.
+
+ @param cs Pointer to charset info.
+ @param str Pointer to start of multi-byte string.
+ @param end Pointer to end of multi-byte string.
+ @param c Character to find first occurrence of.
+
+ @return Pointer to first occurence of c in str or NULL.
+*/
+
+char *my_strchr(const CHARSET_INFO *cs, const char *str, const char *end,
+ pchar c)
+{
+ while (str < end)
+ {
+ uint mbl= my_mbcharlen_ptr(cs, str, end);
+ if (mbl == 0)
+ return NULL;
+ if (mbl == 1)
+ {
+ if (*str == c)
+ return((char *)str);
+ str++;
+ }
+ else
+ str+= mbl;
+ }
+ return(0);
+}
+
+
+/**
+ Calculate the length of the initial segment of 'str' which consists
+ entirely of characters not in 'reject'.
+
+ @param cs Pointer to charset info.
+ @param str Pointer to multi-byte string.
+ @param str_end Pointer to end of multi-byte string.
+ @param reject Pointer to start of single-byte reject string.
+ @param reject_length Length of single-byte reject string.
+
+ @return Length of segment of multi-byte string that doesn't contain
+ any character of the single-byte reject string or zero if an
+ invalid encoding of a character of the multi-byte string is
+ found.
+
+ @note The reject string points to single-byte characters so it is
+ only possible to find the first occurrence of a single-byte
+ character. Multi-byte characters in 'str' are treated as not
+ matching any character in the reject string.
+ This method returns zero if an invalid encoding of any character
+ in the string 'str' using charset 'cs' is found.
+
+ @todo should be moved to CHARSET_INFO if it's going to be called
+ frequently.
+
+ @internal The implementation builds on the assumption that 'str' is long,
+ while 'reject' is short. So it compares each character in string
+ with the characters in 'reject' in a tight loop over the characters
+ in 'reject'.
+*/
+
+size_t my_strcspn(const CHARSET_INFO *cs, const char *str,
+ const char *str_end, const char *reject,
+ size_t reject_length)
+{
+ const char *ptr_str, *ptr_reject;
+ const char *reject_end= reject + reject_length;
+ uint mbl= 0;
+
+ for (ptr_str= str; ptr_str < str_end; ptr_str+= mbl)
+ {
+ mbl= my_mbcharlen_ptr(cs, ptr_str, str_end);
+
+ if (mbl == 0)
+ return 0;
+
+ if (mbl == 1)
+ {
+ for (ptr_reject= reject; ptr_reject < reject_end; ++ptr_reject)
+ {
+ if (*ptr_reject == *ptr_str)
+ return (size_t) (ptr_str - str);
+ }
+ }
+ }
+ return (size_t) (ptr_str - str);
+}