/* Locale dependent memory area transformation for comparison.
- Copyright (C) 2009 Free Software Foundation, Inc.
+ Copyright (C) 2009, 2010 Free Software Foundation, Inc.
Written by Bruno Haible <bruno@clisp.org>, 2009.
This program is free software: you can redistribute it and/or modify it
#include <string.h>
char *
-memxfrm (char *s, size_t n, size_t *lengthp)
+memxfrm (char *s, size_t n, char *resultbuf, size_t *lengthp)
{
/* Result accumulator. */
char *result;
char orig_sentinel;
/* Initial memory allocation. */
- allocated = (n > 0 ? n : 1);
- result = (char *) malloc (allocated);
- if (result == NULL)
- goto out_of_memory_2;
+ if (resultbuf != NULL && *lengthp > 0)
+ {
+ result = resultbuf;
+ allocated = *lengthp;
+ }
+ else
+ {
+ allocated = (n > 0 ? n : 1);
+ result = (char *) malloc (allocated);
+ if (result == NULL)
+ goto out_of_memory_2;
+ }
length = 0;
/* Add sentinel.byte. */
p = s;
for (;;)
{
- /* Search next NUL byte. */
- const char *q = p + strlen (p);
-
- for (;;)
- {
- size_t k;
-
- errno = 0;
- k = strxfrm (result + length, p, allocated - length);
- if (errno != 0)
- goto fail;
- if (k >= allocated - length)
- {
- /* Grow the result buffer. */
- char *new_result;
-
- allocated = 2 * allocated;
- new_result = (char *) realloc (result, allocated);
- if (new_result == NULL)
- goto out_of_memory_1;
- result = new_result;
- }
- else
- {
- length += k;
- break;
- }
- }
-
- p = q + 1;
- if (p == p_end)
- break;
- result[length] = '\0';
+ /* Search next NUL byte. */
+ const char *q = p + strlen (p);
+
+ for (;;)
+ {
+ size_t k;
+
+ errno = 0;
+ k = strxfrm (result + length, p, allocated - length);
+ if (errno != 0)
+ goto fail;
+ if (k >= allocated - length)
+ {
+ /* Grow the result buffer. */
+ char *new_result;
+
+ allocated = 2 * allocated;
+ if (allocated < 64)
+ allocated = 64;
+ if (result == resultbuf)
+ new_result = (char *) malloc (allocated);
+ else
+ new_result = (char *) realloc (result, allocated);
+ if (new_result == NULL)
+ goto out_of_memory_1;
+ result = new_result;
+ }
+ else
+ {
+ length += k;
+ break;
+ }
+ }
+
+ p = q + 1;
+ if (p == p_end)
+ break;
+ result[length] = '\0';
length++;
}
}
/* Shrink the allocated memory if possible. */
- if ((length > 0 ? length : 1) < allocated)
+ if (result != resultbuf && (length > 0 ? length : 1) < allocated)
{
char *memory = (char *) realloc (result, length > 0 ? length : 1);
if (memory != NULL)
- result = memory;
+ result = memory;
}
s[n] = orig_sentinel;
fail:
{
int saved_errno = errno;
- free (result);
+ if (result != resultbuf)
+ free (result);
s[n] = orig_sentinel;
errno = saved_errno;
return NULL;
}
out_of_memory_1:
- free (result);
+ if (result != resultbuf)
+ free (result);
s[n] = orig_sentinel;
out_of_memory_2:
errno = ENOMEM;