newlib-cygwin/newlib/libc/argz/argz_replace.c

84 lines
2.2 KiB
C

/* Copyright (C) 2002 by Red Hat, Incorporated. All rights reserved.
*
* Permission to use, copy, modify, and distribute this software
* is freely granted, provided that this notice is preserved.
*/
#include <errno.h>
#include <sys/types.h>
#include <string.h>
#include <stdlib.h>
#include <argz.h>
extern int buf_findstr(const char *str, char **buf, size_t *buf_len);
error_t
argz_replace (char **argz, size_t *argz_len, const char *str, const char *with, unsigned *replace_count)
{
const int str_len = strlen(str);
const int with_len = strlen(with);
const int len_diff = with_len - str_len;
char *buf_iter = *argz;
size_t buf_len = *argz_len;
char *last_iter = NULL;
char *new_argz = NULL;
size_t new_argz_len = 0;
char *new_argz_iter = NULL;
*replace_count = 0;
new_argz_len = *argz_len;
while(buf_len)
{
if(buf_findstr(str, &buf_iter, &buf_len))
{
*replace_count += 1;
new_argz_len += len_diff;
}
}
if (*replace_count)
{
new_argz = (char *)malloc(new_argz_len);
buf_iter = *argz;
buf_len = *argz_len;
last_iter = buf_iter;
new_argz_iter = new_argz;
while(buf_len)
{
if (buf_findstr(str, &buf_iter, &buf_len))
{
/* copy everything up to, but not including str, from old argz to
new argz. */
memcpy(new_argz_iter, last_iter, buf_iter - last_iter - str_len);
new_argz_iter += (buf_iter - last_iter - str_len);
/* copy replacement string. */
memcpy(new_argz_iter, with, with_len);
new_argz_iter += with_len;
last_iter = buf_iter;
}
}
/* copy everything after last occurrence of str. */
memcpy(new_argz_iter, last_iter, *argz + *argz_len - last_iter);
/* reallocate argz, and copy over the new value. */
if(!(*argz = (char *)realloc(*argz, new_argz_len)))
return ENOMEM;
memcpy(*argz, new_argz, new_argz_len);
*argz_len = new_argz_len;
if (*argz_len == 0)
{
free(*argz);
*argz = NULL;
}
free(new_argz);
}
return 0;
}