grub/grub-core/commands/search.c
Vladimir 'phcoder' Serbinenko f4d5a8ce56 search cache
2011-12-23 21:14:34 +01:00

313 lines
6.5 KiB
C

/* search.c - search devices based on a file or a filesystem label */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2005,2007,2008,2009 Free Software Foundation, Inc.
*
* GRUB 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 3 of the License, or
* (at your option) any later version.
*
* GRUB 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 GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <grub/types.h>
#include <grub/misc.h>
#include <grub/mm.h>
#include <grub/err.h>
#include <grub/dl.h>
#include <grub/device.h>
#include <grub/file.h>
#include <grub/env.h>
#include <grub/command.h>
#include <grub/search.h>
#include <grub/i18n.h>
#include <grub/disk.h>
#include <grub/partition.h>
GRUB_MOD_LICENSE ("GPLv3+");
struct cache_entry
{
struct cache_entry *next;
char *key;
char *value;
};
static struct cache_entry *cache;
void
FUNC_NAME (const char *key, const char *var, int no_floppy,
char **hints, unsigned nhints)
{
int count = 0;
int is_cache = 0;
grub_fs_autoload_hook_t saved_autoload;
auto int iterate_device (const char *name);
int iterate_device (const char *name)
{
int found = 0;
/* Skip floppy drives when requested. */
if (no_floppy &&
name[0] == 'f' && name[1] == 'd' && name[2] >= '0' && name[2] <= '9')
return 0;
#ifdef DO_SEARCH_FS_UUID
#define compare_fn grub_strcasecmp
#else
#define compare_fn grub_strcmp
#endif
#ifdef DO_SEARCH_FILE
{
char *buf;
grub_file_t file;
buf = grub_xasprintf ("(%s)%s", name, key);
if (! buf)
return 1;
grub_file_filter_disable_compression ();
file = grub_file_open (buf);
if (file)
{
found = 1;
grub_file_close (file);
}
grub_free (buf);
}
#else
{
/* SEARCH_FS_UUID or SEARCH_LABEL */
grub_device_t dev;
grub_fs_t fs;
char *quid;
dev = grub_device_open (name);
if (dev)
{
fs = grub_fs_probe (dev);
#ifdef DO_SEARCH_FS_UUID
#define read_fn uuid
#else
#define read_fn label
#endif
if (fs && fs->read_fn)
{
fs->read_fn (dev, &quid);
if (grub_errno == GRUB_ERR_NONE && quid)
{
if (compare_fn (quid, key) == 0)
found = 1;
grub_free (quid);
}
}
grub_device_close (dev);
}
}
#endif
if (!is_cache && found && count == 0)
{
struct cache_entry *cache_ent;
cache_ent = grub_malloc (sizeof (*cache_ent));
if (cache_ent)
{
cache_ent->key = grub_strdup (key);
cache_ent->value = grub_strdup (name);
if (cache_ent->value && cache_ent->key)
{
cache_ent->next = cache;
cache = cache_ent;
}
else
{
grub_free (cache_ent->value);
grub_free (cache_ent->key);
grub_free (cache_ent);
grub_errno = GRUB_ERR_NONE;
}
}
else
grub_errno = GRUB_ERR_NONE;
}
if (found)
{
count++;
if (var)
grub_env_set (var, name);
else
grub_printf (" %s", name);
}
grub_errno = GRUB_ERR_NONE;
return (found && var);
}
auto int part_hook (grub_disk_t disk, const grub_partition_t partition);
int part_hook (grub_disk_t disk, const grub_partition_t partition)
{
char *partition_name, *devname;
int ret;
partition_name = grub_partition_get_name (partition);
if (! partition_name)
return 1;
devname = grub_xasprintf ("%s,%s", disk->name, partition_name);
grub_free (partition_name);
if (!devname)
return 1;
ret = iterate_device (devname);
grub_free (devname);
return ret;
}
auto void try (void);
void try (void)
{
unsigned i;
struct cache_entry **prev;
struct cache_entry *cache_ent;
for (prev = &cache, cache_ent = *prev; cache_ent;
prev = &cache_ent->next, cache_ent = *prev)
if (compare_fn (cache_ent->key, key) == 0)
break;
if (cache_ent)
{
is_cache = 1;
if (iterate_device (cache_ent->value))
{
is_cache = 0;
return;
}
is_cache = 0;
/* Cache entry was outdated. Remove it. */
if (!count)
{
grub_free (cache_ent->key);
grub_free (cache_ent->value);
grub_free (cache_ent);
*prev = cache_ent->next;
}
}
for (i = 0; i < nhints; i++)
{
char *end;
if (!hints[i][0])
continue;
end = hints[i] + grub_strlen (hints[i]) - 1;
if (*end == ',')
*end = 0;
if (iterate_device (hints[i]))
{
if (!*end)
*end = ',';
return;
}
if (!*end)
{
grub_device_t dev;
int ret;
dev = grub_device_open (hints[i]);
if (!dev)
{
if (!*end)
*end = ',';
continue;
}
if (!dev->disk)
{
grub_device_close (dev);
if (!*end)
*end = ',';
continue;
}
ret = grub_partition_iterate (dev->disk, part_hook);
if (!*end)
*end = ',';
grub_device_close (dev);
if (ret)
return;
}
}
grub_device_iterate (iterate_device);
}
/* First try without autoloading if we're setting variable. */
if (var)
{
saved_autoload = grub_fs_autoload_hook;
grub_fs_autoload_hook = 0;
try ();
/* Restore autoload hook. */
grub_fs_autoload_hook = saved_autoload;
/* Retry with autoload if nothing found. */
if (grub_errno == GRUB_ERR_NONE && count == 0)
try ();
}
else
try ();
if (grub_errno == GRUB_ERR_NONE && count == 0)
grub_error (GRUB_ERR_FILE_NOT_FOUND, "no such device: %s", key);
}
static grub_err_t
grub_cmd_do_search (grub_command_t cmd __attribute__ ((unused)), int argc,
char **args)
{
if (argc == 0)
return grub_error (GRUB_ERR_BAD_ARGUMENT, "no argument specified");
FUNC_NAME (args[0], argc == 1 ? 0 : args[1], 0, (args + 2),
argc > 2 ? argc - 2 : 0);
return grub_errno;
}
static grub_command_t cmd;
#ifdef DO_SEARCH_FILE
GRUB_MOD_INIT(search_fs_file)
#elif defined (DO_SEARCH_FS_UUID)
GRUB_MOD_INIT(search_fs_uuid)
#else
GRUB_MOD_INIT(search_label)
#endif
{
cmd =
grub_register_command (COMMAND_NAME, grub_cmd_do_search,
N_("NAME [VARIABLE] [HINTS]"),
HELP_MESSAGE);
}
#ifdef DO_SEARCH_FILE
GRUB_MOD_FINI(search_fs_file)
#elif defined (DO_SEARCH_FS_UUID)
GRUB_MOD_FINI(search_fs_uuid)
#else
GRUB_MOD_FINI(search_label)
#endif
{
grub_unregister_command (cmd);
}