Mercurial > hg > octave-kai > gnulib-hg
changeset 11283:1ca1fb00ca36
New module 'memxfrm'.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Sat, 07 Mar 2009 13:38:02 +0100 |
parents | 61dfd8dc1a13 |
children | ee7917a3f050 11b1a7b0a788 |
files | ChangeLog lib/memxfrm.c lib/memxfrm.h modules/memxfrm |
diffstat | 4 files changed, 197 insertions(+), 0 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,10 @@ +2009-03-07 Bruno Haible <bruno@clisp.org> + + New module 'memxfrm'. + * lib/memxfrm.h: New file. + * lib/memxfrm.c: New file. + * modules/memxfrm: New file. + 2009-03-07 Bruno Haible <bruno@clisp.org> New module 'memcmp2'.
new file mode 100644 --- /dev/null +++ b/lib/memxfrm.c @@ -0,0 +1,122 @@ +/* Locale dependent memory area transformation for comparison. + Copyright (C) 2009 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 + under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#include <config.h> + +/* Specification. */ +#include "memxfrm.h" + +#include <errno.h> +#include <stdlib.h> +#include <string.h> + +char * +memxfrm (char *s, size_t n, size_t *lengthp) +{ + /* Result accumulator. */ + char *result; + size_t length; + size_t allocated; + + char orig_sentinel; + + /* Initial memory allocation. */ + allocated = (n > 0 ? n : 1); + result = (char *) malloc (allocated); + if (result == NULL) + goto out_of_memory_2; + length = 0; + + /* Add sentinel.byte. */ + orig_sentinel = s[n]; + s[n] = '\0'; + + /* Iterate through S, transforming each NUL terminated segment. + Accumulate the resulting transformed segments in result, separated by + NULs. */ + { + const char *p_end = s + n + 1; + const char *p; + + 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'; + length++; + } + } + + /* Shrink the allocated memory if possible. */ + if ((length > 0 ? length : 1) < allocated) + { + char *memory = (char *) realloc (result, length > 0 ? length : 1); + if (memory != NULL) + result = memory; + } + + s[n] = orig_sentinel; + *lengthp = length; + return result; + + fail: + { + int saved_errno = errno; + free (result); + s[n] = orig_sentinel; + errno = saved_errno; + return NULL; + } + + out_of_memory_1: + free (result); + s[n] = orig_sentinel; + out_of_memory_2: + errno = ENOMEM; + return NULL; +}
new file mode 100644 --- /dev/null +++ b/lib/memxfrm.h @@ -0,0 +1,46 @@ +/* Locale dependent memory area transformation for comparison. + Copyright (C) 2009 Free Software Foundation, Inc. + + This program is free software: you can redistribute it and/or modify it + under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + + 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 + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. */ + +#ifndef MEMXFRM_H +#define MEMXFRM_H + +#include <stddef.h> + +#ifdef __cplusplus +extern "C" { +#endif + + +/* Generalization of strxfrm() to strings with embedded NUL bytes. */ + +/* Transform the memory area [S..S+N-1] to a memory area, in such a way that + comparing (S1,N1) and (S2,N2) with memcoll() is equivalent to comparing + memxfrm(S1,N1) and memxfrm(S2,N2) with memcmp2(). + The byte S[N] may be temporarily overwritten by this function, but will be + restored before this function returns. + The result of this function depends on the LC_COLLATE category of the + current locale. + If successful, return the freshly allocated transformed string and set + *LENGTHP to its length, + Upon failure, return NULL, with errno set. */ +extern char * memxfrm (char *s, size_t n, size_t *lengthp); + + +#ifdef __cplusplus +} +#endif + +#endif /* MEMXFRM_H */
new file mode 100644 --- /dev/null +++ b/modules/memxfrm @@ -0,0 +1,22 @@ +Description: +Locale dependent memory area transformation for comparison. + +Files: +lib/memxfrm.h +lib/memxfrm.c + +Depends-on: + +configure.ac: + +Makefile.am: +lib_SOURCES += memxfrm.c + +Include: +"memxfrm.h" + +License: +LGPL + +Maintainer: +Bruno Haible