sortix-mirror/libc/dirent/dscandir_r.c

87 lines
2.7 KiB
C

/*******************************************************************************
Copyright(C) Jonas 'Sortie' Termansen 2013, 2014.
This file is part of the Sortix C Library.
The Sortix C Library 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.
The Sortix C Library 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 the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
dirent/dscandir_r.c
Filtered and sorted directory reading.
*******************************************************************************/
#include <dirent.h>
#include <errno.h>
#include <limits.h>
#include <stdbool.h>
#include <stdlib.h>
#include <string.h>
int dscandir_r(DIR* dir,
struct dirent*** namelist_ptr,
int (*filter)(const struct dirent*, void*),
void* filter_ctx,
int (*compare)(const struct dirent**, const struct dirent**, void*),
void* compare_ctx)
{
rewinddir(dir);
size_t namelist_used = 0;
size_t namelist_length = 0;
struct dirent** namelist = NULL;
if ( false )
{
out_error:
for ( size_t i = 0; i < namelist_used; i++ )
free(namelist[i]);
free(namelist);
return errno = EOVERFLOW, -1;
}
struct dirent* entry;
while ( (entry = readdir(dir)) )
{
if ( filter && !filter(entry, filter_ctx) )
continue;
if ( (size_t) INT_MAX <= namelist_used )
goto out_error;
if ( namelist_used == namelist_length )
{
size_t new_length = namelist_length ? 2 * namelist_length : 8;
size_t new_size = new_length * sizeof(struct dirent*);
struct dirent** list = (struct dirent**) realloc(namelist, new_size);
if ( !list )
goto out_error;
namelist = list;
namelist_length = new_length;
}
size_t name_length = strlen(entry->d_name);
size_t dirent_size = sizeof(struct dirent) + name_length + 1;
struct dirent* dirent = (struct dirent*) malloc(dirent_size);
if ( !dirent )
goto out_error;
memcpy(dirent, entry, sizeof(*entry));
strcpy(dirent->d_name, entry->d_name);
namelist[namelist_used++] = dirent;
}
if ( compare )
qsort_r(namelist, namelist_used, sizeof(struct dirent*),
(int (*)(const void*, const void*, void*)) compare, compare_ctx);
return *namelist_ptr = namelist, (int) namelist_used;
}