/* guestfish - the filesystem interactive shell
- * Copyright (C) 2009 Red Hat Inc.
+ * Copyright (C) 2009 Red Hat 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
#include <config.h>
-#define _GNU_SOURCE // for strndup, asprintf
-
#include <stdio.h>
#include <stdlib.h>
+#include <stddef.h>
#include <string.h>
#ifdef HAVE_LIBREADLINE
#include "fish.h"
+// From gnulib's xalloc.h:
+/* Return 1 if an array of N objects, each of size S, cannot exist due
+ to size arithmetic overflow. S must be positive and N must be
+ nonnegative. This is a macro, not an inline function, so that it
+ works correctly even when SIZE_MAX < N.
+
+ By gnulib convention, SIZE_MAX represents overflow in size
+ calculations, so the conservative dividend to use here is
+ SIZE_MAX - 1, since SIZE_MAX might represent an overflowed value.
+ However, malloc (SIZE_MAX) fails on all known hosts where
+ sizeof (ptrdiff_t) <= sizeof (size_t), so do not bother to test for
+ exactly-SIZE_MAX allocations on such hosts; this avoids a test and
+ branch when S is known to be 1. */
+# define xalloc_oversized(n, s) \
+ ((size_t) (sizeof (ptrdiff_t) <= sizeof (size_t) ? -1 : -2) / (s) < (n))
+
/* Readline completion for paths on the guest filesystem, also for
* devices and LVM names.
*/
-int complete_dest_paths = 0; /* SEE NOTE */
+int complete_dest_paths = 1;
-/* NOTE: This is currently disabled by default (with no way to
- * enable it). That's because it's not particularly natural.
- *
- * Also there is a quite serious performance problem. When listing
- * even moderately long directories, this takes many seconds. The
- * reason is because it calls guestfs_is_dir on each directory
- * entry, thus lots of round trips to the server. We could have
- * a "readdir and stat each entry" call to ease this.
- */
+struct word {
+ char *name;
+ int is_dir;
+};
+
+static void
+free_words (struct word *words, size_t nr_words)
+{
+ size_t i;
+
+ /* NB. 'words' array is NOT NULL-terminated. */
+ for (i = 0; i < nr_words; ++i)
+ free (words[i].name);
+ free (words);
+}
char *
complete_dest_paths_generator (const char *text, int state)
{
#ifdef HAVE_LIBREADLINE
- static int len, index;
- static char **words = NULL;
- static int nr_words = 0;
- char *word;
+ static size_t len, index;
+ static struct word *words = NULL;
+ static size_t nr_words = 0;
guestfs_error_handler_cb old_error_cb;
void *old_error_cb_data;
if (!state) {
char **strs;
- int i, n;
len = strlen (text);
index = 0;
- if (words) {
- /* NB. 'words' array is NOT NULL-terminated. */
- for (i = 0; i < nr_words; ++i)
- free (words[i]);
- free (words);
- }
+ if (words) free_words (words, nr_words);
words = NULL;
nr_words = 0;
SAVE_ERROR_CB
+/* Silently do nothing if an allocation fails */
#define APPEND_STRS_AND_FREE \
+ do { \
if (strs) { \
- n = count_strings (strs); \
- words = realloc (words, sizeof (char *) * (nr_words + n)); \
- for (i = 0; i < n; ++i) \
- words[nr_words++] = strs[i]; \
+ size_t i; \
+ size_t n = count_strings (strs); \
+ \
+ if ( n > 0 && ! xalloc_oversized (nr_words + n, sizeof (struct word))) { \
+ struct word *w; \
+ w = realloc (words, sizeof (struct word) * (nr_words + n)); \
+ \
+ if (w == NULL) { \
+ free_words (words, nr_words); \
+ words = NULL; \
+ nr_words = 0; \
+ } else { \
+ words = w; \
+ for (i = 0; i < n; ++i) { \
+ words[nr_words].name = strs[i]; \
+ words[nr_words].is_dir = 0; \
+ nr_words++; \
+ } \
+ } \
+ } \
free (strs); \
- }
+ } \
+ } while (0)
/* Is it a device? */
if (len < 5 || strncmp (text, "/dev/", 5) == 0) {
/* Get a list of everything that can possibly begin with /dev/ */
strs = guestfs_list_devices (g);
- APPEND_STRS_AND_FREE
+ APPEND_STRS_AND_FREE;
strs = guestfs_list_partitions (g);
- APPEND_STRS_AND_FREE
+ APPEND_STRS_AND_FREE;
strs = guestfs_lvs (g);
- APPEND_STRS_AND_FREE
+ APPEND_STRS_AND_FREE;
}
if (len < 1 || text[0] == '/') {
* in that directory, otherwise list everything in /
*/
char *p, *dir;
+ struct guestfs_dirent_list *dirents;
p = strrchr (text, '/');
dir = p && p > text ? strndup (text, p - text) : strdup ("/");
-
- strs = guestfs_ls (g, dir);
-
- /* Prepend directory to names. */
- if (strs) {
- for (i = 0; strs[i]; ++i) {
- p = NULL;
- if (strcmp (dir, "/") == 0)
- asprintf (&p, "/%s", strs[i]);
- else
- asprintf (&p, "%s/%s", dir, strs[i]);
- free (strs[i]);
- strs[i] = p;
- }
+ if (dir) {
+ dirents = guestfs_readdir (g, dir);
+
+ /* Prepend directory to names before adding them to the list
+ * of words.
+ */
+ if (dirents) {
+ size_t i;
+
+ for (i = 0; i < dirents->len; ++i) {
+ int err;
+
+ if (strcmp (dirents->val[i].name, ".") != 0 &&
+ strcmp (dirents->val[i].name, "..") != 0) {
+ if (strcmp (dir, "/") == 0)
+ err = asprintf (&p, "/%s", dirents->val[i].name);
+ else
+ err = asprintf (&p, "%s/%s", dir, dirents->val[i].name);
+ if (err >= 0) {
+ if (!xalloc_oversized (nr_words+1, sizeof (struct word))) {
+ struct word *w;
+
+ w = realloc (words, sizeof (struct word) * (nr_words+1));
+ if (w == NULL) {
+ free_words (words, nr_words);
+ words = NULL;
+ nr_words = 0;
+ }
+ else {
+ words = w;
+ words[nr_words].name = p;
+ words[nr_words].is_dir = dirents->val[i].ftyp == 'd';
+ nr_words++;
+ }
+ }
+ }
+ }
+ }
+
+ guestfs_free_dirent_list (dirents);
+ }
}
-
- free (dir);
- APPEND_STRS_AND_FREE
}
/* else ... In theory we could complete other things here such as VG
/* Complete the string. */
while (index < nr_words) {
- word = words[index];
+ struct word *word;
+
+ word = &words[index];
index++;
- if (strncasecmp (word, text, len) == 0) {
- /* Is it a directory? */
- if (strncmp (word, "/dev/", 5) != 0) {
- SAVE_ERROR_CB
- if (guestfs_is_dir (g, word) > 0)
- rl_completion_append_character = '/';
- RESTORE_ERROR_CB
- }
- return strdup (word);
+ if (strncasecmp (word->name, text, len) == 0) {
+ if (word->is_dir)
+ rl_completion_append_character = '/';
+
+ return strdup (word->name);
}
}