diff options
Diffstat (limited to 'lib/savedir.c')
| -rw-r--r-- | lib/savedir.c | 137 |
1 files changed, 137 insertions, 0 deletions
diff --git a/lib/savedir.c b/lib/savedir.c new file mode 100644 index 0000000..d930fb4 --- /dev/null +++ b/lib/savedir.c @@ -0,0 +1,137 @@ +/* savedir.c -- save the list of files in a directory in a string + + Copyright (C) 1990, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005, + 2006 Free Software Foundation, Inc. + + 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; either version 2, 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 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 Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* Written by David MacKenzie <djm@gnu.ai.mit.edu>. */ + +#include <config.h> + +#include "savedir.h" + +#include <sys/types.h> + +#include <errno.h> + +#include <dirent.h> +#ifndef _D_EXACT_NAMLEN +# define _D_EXACT_NAMLEN(dp) strlen ((dp)->d_name) +#endif + +#include <stddef.h> +#include <stdlib.h> +#include <string.h> + +#include "openat.h" +#include "xalloc.h" + +#ifndef NAME_SIZE_DEFAULT +# define NAME_SIZE_DEFAULT 512 +#endif + +/* The results of opendir() in this file are not used with dirfd and fchdir, + therefore save some unnecessary work in fchdir.c. */ +#undef opendir +#undef closedir + +/* Return a freshly allocated string containing the file names + in directory DIRP, separated by '\0' characters; + the end is marked by two '\0' characters in a row. + Return NULL (setting errno) if DIRP cannot be read or closed. + If DIRP is NULL, return NULL without affecting errno. */ + +static char * +savedirstream (DIR *dirp) +{ + char *name_space; + size_t allocated = NAME_SIZE_DEFAULT; + size_t used = 0; + int save_errno; + + if (dirp == NULL) + return NULL; + + name_space = xmalloc (allocated); + + for (;;) + { + struct dirent const *dp; + char const *entry; + + errno = 0; + dp = readdir (dirp); + if (! dp) + break; + + /* Skip "", ".", and "..". "" is returned by at least one buggy + implementation: Solaris 2.4 readdir on NFS file systems. */ + entry = dp->d_name; + if (entry[entry[0] != '.' ? 0 : entry[1] != '.' ? 1 : 2] != '\0') + { + size_t entry_size = _D_EXACT_NAMLEN (dp) + 1; + if (used + entry_size < used) + xalloc_die (); + if (allocated <= used + entry_size) + { + do + { + if (2 * allocated < allocated) + xalloc_die (); + allocated *= 2; + } + while (allocated <= used + entry_size); + + name_space = xrealloc (name_space, allocated); + } + memcpy (name_space + used, entry, entry_size); + used += entry_size; + } + } + name_space[used] = '\0'; + save_errno = errno; + if (closedir (dirp) != 0) + save_errno = errno; + if (save_errno != 0) + { + free (name_space); + errno = save_errno; + return NULL; + } + return name_space; +} + +/* Return a freshly allocated string containing the file names + in directory DIR, separated by '\0' characters; + the end is marked by two '\0' characters in a row. + Return NULL (setting errno) if DIR cannot be opened, read, or closed. */ + +char * +savedir (char const *dir) +{ + return savedirstream (opendir (dir)); +} + +/* Return a freshly allocated string containing the file names + in directory FD, separated by '\0' characters; + the end is marked by two '\0' characters in a row. + Return NULL (setting errno) if FD cannot be read or closed. */ + +char * +fdsavedir (int fd) +{ + return savedirstream (fdopendir (fd)); +} |