+2014-02-11 Sergey Poznyakoff <gray@gnu.org.ua>
+ Paul Eggert <eggert@cs.ucla.edu>
+
+ savedir: add sorting arg to savedir, streamsavedir; remove fdsavedir
+ Patch based on an idea by Dick Streefland in
+ <https://savannah.gnu.org/patch/?7892>.
+ * NEWS: Document this.
+ * lib/savedir.c (NAME_SIZE_DEFAULT): Remove.
+ (direntry_t, comparison_function): New types.
+ (direntry_cmp_name): New function.
+ (direntry_cmp_inode) [D_INO_IN_DIRENT]: New function.
+ (streamsavedir, savedir): New arg OPTION.
+ (streamsavedir): Simplify memory allocation.
+ (fdsavedir): Remove.
+ * lib/savedir.h (enum savedir_option): New type.
+ (streamsavedir, savedir): New arg OPTION.
+ (fdsavedir): Remove.
+
2014-02-05 Paul Eggert <eggert@cs.ucla.edu>
file-type: add support for doors and other less-common file types
#include "xalloc.h"
-#ifndef NAME_SIZE_DEFAULT
-# define NAME_SIZE_DEFAULT 512
+typedef struct
+{
+ char *name;
+ size_t size;
+#if D_INO_IN_DIRENT
+ ino_t ino;
+#endif
+} direntry_t;
+
+/* Compare the names of two directory entries */
+
+static int
+direntry_cmp_name (void const *a, void const *b)
+{
+ direntry_t const *dea = a;
+ direntry_t const *deb = b;
+
+ return strcmp (dea->name, deb->name);
+}
+
+#if D_INO_IN_DIRENT
+/* Compare the inode numbers of two directory entries */
+
+static int
+direntry_cmp_inode (void const *a, void const *b)
+{
+ direntry_t const *dea = a;
+ direntry_t const *deb = b;
+
+ return dea->ino < deb->ino ? -1 : dea->ino > deb->ino;
+}
+#endif
+
+typedef int (*comparison_function) (void const *, void const *);
+
+static comparison_function const comparison_function_table[] =
+ {
+ 0,
+ direntry_cmp_name
+#if D_INO_IN_DIRENT
+ , direntry_cmp_inode
#endif
+ };
/* 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.
+ Returned values are sorted according to OPTION.
Return NULL (setting errno) if DIRP cannot be read.
If DIRP is NULL, return NULL without affecting errno. */
char *
-streamsavedir (DIR *dirp)
+streamsavedir (DIR *dirp, enum savedir_option option)
{
- char *name_space;
- size_t allocated = NAME_SIZE_DEFAULT;
+ char *name_space = NULL;
+ size_t allocated = 0;
+ direntry_t *entries = NULL;
+ size_t entries_allocated = 0;
+ size_t entries_used = 0;
size_t used = 0;
- int save_errno;
+ int readdir_errno;
+ comparison_function cmp = comparison_function_table[option];
if (dirp == NULL)
return NULL;
- name_space = xmalloc (allocated);
-
for (;;)
{
struct dirent const *dp;
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)
+ if (cmp)
{
- do
+ if (entries_allocated == entries_used)
{
- if (2 * allocated < allocated)
- xalloc_die ();
- allocated *= 2;
+ size_t n = entries_allocated;
+ entries = x2nrealloc (entries, &n, sizeof *entries);
+ entries_allocated = n;
}
- while (allocated <= used + entry_size);
-
- name_space = xrealloc (name_space, allocated);
+ entries[entries_used].name = xstrdup (entry);
+ entries[entries_used].size = entry_size;
+#if D_INO_IN_DIRENT
+ entries[entries_used].ino = dp->d_ino;
+#endif
+ entries_used++;
}
- memcpy (name_space + used, entry, entry_size);
- used += entry_size;
+ else
+ {
+ if (allocated - used <= entry_size)
+ {
+ size_t n = used + entry_size;
+ if (n < used)
+ xalloc_die ();
+ name_space = x2nrealloc (name_space, &n, 1);
+ allocated = n;
+ }
+ memcpy (name_space + used, entry, entry_size);
+ }
+ used += entry_size;
}
}
- name_space[used] = '\0';
- save_errno = errno;
- if (save_errno != 0)
+
+ readdir_errno = errno;
+ if (readdir_errno != 0)
{
+ free (entries);
free (name_space);
- errno = save_errno;
+ errno = readdir_errno;
return NULL;
}
- return name_space;
-}
-/* Like streamsavedir (DIRP), except also close DIRP. */
-
-static char *
-savedirstream (DIR *dirp)
-{
- char *name_space = streamsavedir (dirp);
- if (dirp && closedir (dirp) != 0)
+ if (cmp)
{
- int save_errno = errno;
- free (name_space);
- errno = save_errno;
- return NULL;
+ size_t i;
+
+ qsort (entries, entries_used, sizeof *entries, cmp);
+ name_space = xmalloc (used + 1);
+ used = 0;
+ for (i = 0; i < entries_used; i++)
+ {
+ memcpy (name_space + used, entries[i].name, entries[i].size);
+ used += entries[i].size;
+ free (entries[i].name);
+ }
+ free (entries);
}
+ else if (used == allocated)
+ name_space = xrealloc (name_space, used + 1);
+
+ name_space[used] = '\0';
return name_space;
}
Return NULL (setting errno) if DIR cannot be opened, read, or closed. */
char *
-savedir (char const *dir)
+savedir (char const *dir, enum savedir_option option)
{
- 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. */
-
-/* deprecated */
-char *
-fdsavedir (int fd)
-{
- return savedirstream (fdopendir (fd));
+ DIR *dirp = opendir (dir);
+ if (! dirp)
+ return NULL;
+ else
+ {
+ char *name_space = streamsavedir (dirp, option);
+ if (closedir (dirp) != 0)
+ {
+ int closedir_errno = errno;
+ free (name_space);
+ errno = closedir_errno;
+ return NULL;
+ }
+ return name_space;
+ }
}