grub/grub-core/commands/wildcard.c

653 lines
12 KiB
C
Raw Normal View History

/* wildcard.c - Wildcard character expansion for GRUB script. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2010 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/mm.h>
#include <grub/fs.h>
#include <grub/env.h>
#include <grub/file.h>
#include <grub/device.h>
#include <grub/script_sh.h>
#include <grub/safemath.h>
#include <regex.h>
static inline int isregexop (char ch);
static char ** merge (char **lhs, char **rhs);
static char *make_dir (const char *prefix, const char *start, const char *end);
static int make_regex (const char *regex_start, const char *regex_end,
regex_t *regexp);
static void split_path (const char *path, const char **suffix_end, const char **regex_end);
static char ** match_devices (const regex_t *regexp, int noparts);
static char ** match_files (const char *prefix, const char *suffix_start,
const char *suffix_end, const regex_t *regexp);
static grub_err_t wildcard_expand (const char *s, char ***strs);
2010-09-03 15:05:23 +00:00
struct grub_script_wildcard_translator grub_filename_translator = {
.expand = wildcard_expand,
};
static char **
merge (char **dest, char **ps)
{
int i;
int j;
char **p;
grub_size_t sz;
if (! dest)
return ps;
if (! ps)
return dest;
for (i = 0; dest[i]; i++)
;
for (j = 0; ps[j]; j++)
;
if (grub_add (i, j, &sz) ||
grub_add (sz, 1, &sz) ||
grub_mul (sz, sizeof (char *), &sz))
return dest;
p = grub_realloc (dest, sz);
if (! p)
{
grub_free (dest);
grub_free (ps);
return 0;
}
dest = p;
for (j = 0; ps[j]; j++)
dest[i++] = ps[j];
dest[i] = 0;
grub_free (ps);
return dest;
}
static inline int
isregexop (char ch)
{
return grub_strchr ("*.\\|+{}[]?", ch) ? 1 : 0;
}
static char *
make_dir (const char *prefix, const char *start, const char *end)
{
char ch;
unsigned i;
unsigned n;
char *result;
i = grub_strlen (prefix);
n = i + end - start;
result = grub_malloc (n + 1);
if (! result)
return 0;
grub_strcpy (result, prefix);
while (start < end && (ch = *start++))
if (ch == '\\' && isregexop (*start))
result[i++] = *start++;
else
result[i++] = ch;
result[i] = '\0';
return result;
}
static int
make_regex (const char *start, const char *end, regex_t *regexp)
{
char ch;
int i = 0;
unsigned len = end - start;
char *buffer;
grub_size_t sz;
/* Worst case size is (len * 2 + 2 + 1). */
if (grub_mul (len, 2, &sz) ||
grub_add (sz, 3, &sz))
return 1;
buffer = grub_malloc (sz);
if (! buffer)
return 1;
buffer[i++] = '^';
while (start < end)
{
/* XXX Only * and ? expansion for now. */
switch ((ch = *start++))
{
case '\\':
buffer[i++] = ch;
if (*start != '\0')
buffer[i++] = *start++;
break;
case '.':
case '(':
case ')':
case '@':
case '+':
case '|':
case '{':
case '}':
case '[':
case ']':
buffer[i++] = '\\';
buffer[i++] = ch;
break;
case '*':
buffer[i++] = '.';
buffer[i++] = '*';
break;
case '?':
buffer[i++] = '.';
break;
default:
buffer[i++] = ch;
}
}
buffer[i++] = '$';
buffer[i] = '\0';
grub_dprintf ("expand", "Regexp is %s\n", buffer);
if (regcomp (regexp, buffer, RE_SYNTAX_GNU_AWK))
{
grub_free (buffer);
return 1;
}
grub_free (buffer);
return 0;
}
/* Split `str' into two parts: (1) dirname that is regexop free (2)
dirname that has a regexop. */
static void
split_path (const char *str, const char **noregexop, const char **regexop)
{
char ch = 0;
int regex = 0;
const char *end;
const char *split; /* points till the end of dirnaname that doesn't
need expansion. */
split = end = str;
while ((ch = *end))
{
if (ch == '\\' && end[1])
end++;
else if (ch == '*' || ch == '?')
regex = 1;
else if (ch == '/' && ! regex)
split = end + 1; /* forward to next regexop-free dirname */
else if (ch == '/' && regex)
break; /* stop at the first dirname with a regexop */
end++;
}
*regexop = end;
if (! regex)
*noregexop = end;
else
*noregexop = split;
}
/* Context for match_devices. */
struct match_devices_ctx
{
const regex_t *regexp;
int noparts;
int ndev;
char **devs;
};
/* Helper for match_devices. */
static int
match_devices_iter (const char *name, void *data)
{
struct match_devices_ctx *ctx = data;
char **t;
char *buffer;
grub_size_t sz;
/* skip partitions if asked to. */
if (ctx->noparts && grub_strchr (name, ','))
return 0;
buffer = grub_xasprintf ("(%s)", name);
if (! buffer)
return 1;
grub_dprintf ("expand", "matching: %s\n", buffer);
if (regexec (ctx->regexp, buffer, 0, 0, 0))
{
grub_dprintf ("expand", "not matched\n");
fail:
grub_free (buffer);
return 0;
}
if (grub_add (ctx->ndev, 2, &sz) ||
grub_mul (sz, sizeof (char *), &sz))
goto fail;
t = grub_realloc (ctx->devs, sz);
if (! t)
{
grub_free (buffer);
return 1;
}
ctx->devs = t;
ctx->devs[ctx->ndev++] = buffer;
ctx->devs[ctx->ndev] = 0;
return 0;
}
static char **
match_devices (const regex_t *regexp, int noparts)
{
struct match_devices_ctx ctx = {
.regexp = regexp,
.noparts = noparts,
.ndev = 0,
.devs = 0
};
int i;
if (grub_device_iterate (match_devices_iter, &ctx))
goto fail;
return ctx.devs;
fail:
for (i = 0; ctx.devs && ctx.devs[i]; i++)
grub_free (ctx.devs[i]);
grub_free (ctx.devs);
return 0;
}
/* Context for match_files. */
struct match_files_ctx
{
const regex_t *regexp;
char **files;
unsigned nfile;
char *dir;
};
/* Helper for match_files. */
static int
match_files_iter (const char *name,
const struct grub_dirhook_info *info __attribute__((unused)),
void *data)
{
struct match_files_ctx *ctx = data;
char **t;
char *buffer;
grub_size_t sz;
/* skip . and .. names */
if (grub_strcmp(".", name) == 0 || grub_strcmp("..", name) == 0)
return 0;
grub_dprintf ("expand", "matching: %s in %s\n", name, ctx->dir);
if (regexec (ctx->regexp, name, 0, 0, 0))
return 0;
grub_dprintf ("expand", "matched\n");
buffer = grub_xasprintf ("%s%s", ctx->dir, name);
if (! buffer)
return 1;
if (grub_add (ctx->nfile, 2, &sz) ||
grub_mul (sz, sizeof (char *), &sz))
goto fail;
t = grub_realloc (ctx->files, sz);
if (!t)
{
fail:
grub_free (buffer);
return 1;
}
ctx->files = t;
ctx->files[ctx->nfile++] = buffer;
ctx->files[ctx->nfile] = 0;
return 0;
}
static char **
match_files (const char *prefix, const char *suffix, const char *end,
const regex_t *regexp)
{
struct match_files_ctx ctx = {
.regexp = regexp,
.nfile = 0,
.files = 0
};
int i;
const char *path;
char *device_name;
grub_fs_t fs;
grub_device_t dev;
dev = 0;
device_name = 0;
grub_error_push ();
ctx.dir = make_dir (prefix, suffix, end);
if (! ctx.dir)
goto fail;
device_name = grub_file_get_device_name (ctx.dir);
dev = grub_device_open (device_name);
if (! dev)
goto fail;
fs = grub_fs_probe (dev);
if (! fs)
goto fail;
if (ctx.dir[0] == '(')
{
path = grub_strchr (ctx.dir, ')');
if (!path)
goto fail;
path++;
}
else
path = ctx.dir;
if (fs->fs_dir (dev, path, match_files_iter, &ctx))
goto fail;
grub_free (ctx.dir);
grub_device_close (dev);
grub_free (device_name);
grub_error_pop ();
return ctx.files;
fail:
grub_free (ctx.dir);
for (i = 0; ctx.files && ctx.files[i]; i++)
grub_free (ctx.files[i]);
grub_free (ctx.files);
if (dev)
grub_device_close (dev);
grub_free (device_name);
grub_error_pop ();
return 0;
}
/* Context for check_file. */
struct check_file_ctx
{
const char *basename;
int found;
};
/* Helper for check_file. */
static int
check_file_iter (const char *name, const struct grub_dirhook_info *info,
void *data)
{
struct check_file_ctx *ctx = data;
if (ctx->basename[0] == 0
|| (info->case_insensitive ? grub_strcasecmp (name, ctx->basename) == 0
: grub_strcmp (name, ctx->basename) == 0))
{
ctx->found = 1;
return 1;
}
return 0;
}
static int
check_file (const char *dir, const char *basename)
{
struct check_file_ctx ctx = {
.basename = basename,
.found = 0
};
grub_fs_t fs;
grub_device_t dev;
const char *device_name, *path;
device_name = grub_file_get_device_name (dir);
dev = grub_device_open (device_name);
if (! dev)
goto fail;
fs = grub_fs_probe (dev);
if (! fs)
goto fail;
if (dir[0] == '(')
{
path = grub_strchr (dir, ')');
if (!path)
goto fail;
path++;
}
else
path = dir;
fs->fs_dir (dev, path[0] ? path : "/", check_file_iter, &ctx);
if (grub_errno == 0 && basename[0] == 0)
ctx.found = 1;
fail:
grub_errno = 0;
return ctx.found;
}
static void
unescape (char *out, const char *in, const char *end)
{
char *optr;
const char *iptr;
for (optr = out, iptr = in; iptr < end;)
{
if (*iptr == '\\' && iptr + 1 < end)
{
*optr++ = iptr[1];
iptr += 2;
continue;
}
if (*iptr == '\\')
break;
*optr++ = *iptr++;
}
*optr = 0;
}
static grub_err_t
wildcard_expand (const char *s, char ***strs)
{
const char *start;
const char *regexop;
const char *noregexop;
char **paths = 0;
int had_regexp = 0;
unsigned i;
regex_t regexp;
*strs = 0;
if (s[0] != '/' && s[0] != '(' && s[0] != '*')
return 0;
start = s;
while (*start)
{
split_path (start, &noregexop, &regexop);
if (noregexop == regexop)
{
grub_dprintf ("expand", "no expansion needed\n");
if (paths == 0)
{
paths = grub_malloc (sizeof (char *) * 2);
if (!paths)
goto fail;
paths[0] = grub_malloc (regexop - start + 1);
if (!paths[0])
goto fail;
unescape (paths[0], start, regexop);
paths[1] = 0;
}
else
{
int j = 0;
for (i = 0; paths[i]; i++)
{
char *o, *oend;
char *n;
char *p;
o = paths[i];
oend = o + grub_strlen (o);
n = grub_malloc ((oend - o) + (regexop - start) + 1);
if (!n)
goto fail;
grub_memcpy (n, o, oend - o);
unescape (n + (oend - o), start, regexop);
if (had_regexp)
p = grub_strrchr (n, '/');
else
p = 0;
if (!p)
{
grub_free (o);
paths[j++] = n;
continue;
}
*p = 0;
if (!check_file (n, p + 1))
{
grub_dprintf ("expand", "file <%s> in <%s> not found\n",
p + 1, n);
grub_free (o);
grub_free (n);
continue;
}
*p = '/';
grub_free (o);
paths[j++] = n;
}
if (j == 0)
{
grub_free (paths);
paths = 0;
goto done;
}
paths[j] = 0;
}
grub_dprintf ("expand", "paths[0] = `%s'\n", paths[0]);
start = regexop;
continue;
}
if (make_regex (noregexop, regexop, &regexp))
goto fail;
had_regexp = 1;
if (paths == 0)
{
if (start == noregexop) /* device part has regexop */
paths = match_devices (&regexp, *start != '(');
else /* device part explicit wo regexop */
paths = match_files ("", start, noregexop, &regexp);
}
else
{
char **r = 0;
for (i = 0; paths[i]; i++)
{
char **p;
p = match_files (paths[i], start, noregexop, &regexp);
grub_free (paths[i]);
if (! p)
continue;
r = merge (r, p);
if (! r)
goto fail;
}
grub_free (paths);
paths = r;
}
regfree (&regexp);
if (! paths)
goto done;
start = regexop;
}
done:
*strs = paths;
return 0;
fail:
for (i = 0; paths && paths[i]; i++)
grub_free (paths[i]);
grub_free (paths);
regfree (&regexp);
return grub_errno;
}