busybox/e2fsprogs/e2p/feature.c
2005-06-11 22:25:27 +00:00

188 lines
3.9 KiB
C

/*
* feature.c --- convert between features and strings
*
* Copyright (C) 1999 Theodore Ts'o <tytso@mit.edu>
*
* This file can be redistributed under the terms of the GNU Library General
* Public License
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <ctype.h>
#include <errno.h>
#include "e2p.h"
struct feature {
int compat;
unsigned int mask;
const char *string;
};
static struct feature feature_list[] = {
{ E2P_FEATURE_COMPAT, EXT2_FEATURE_COMPAT_DIR_PREALLOC,
"dir_prealloc" },
{ E2P_FEATURE_COMPAT, EXT3_FEATURE_COMPAT_HAS_JOURNAL,
"has_journal" },
{ E2P_FEATURE_COMPAT, EXT2_FEATURE_COMPAT_IMAGIC_INODES,
"imagic_inodes" },
{ E2P_FEATURE_COMPAT, EXT2_FEATURE_COMPAT_EXT_ATTR,
"ext_attr" },
{ E2P_FEATURE_COMPAT, EXT2_FEATURE_COMPAT_DIR_INDEX,
"dir_index" },
{ E2P_FEATURE_COMPAT, EXT2_FEATURE_COMPAT_RESIZE_INODE,
"resize_inode" },
{ E2P_FEATURE_RO_INCOMPAT, EXT2_FEATURE_RO_COMPAT_SPARSE_SUPER,
"sparse_super" },
{ E2P_FEATURE_RO_INCOMPAT, EXT2_FEATURE_RO_COMPAT_LARGE_FILE,
"large_file" },
{ E2P_FEATURE_INCOMPAT, EXT2_FEATURE_INCOMPAT_COMPRESSION,
"compression" },
{ E2P_FEATURE_INCOMPAT, EXT2_FEATURE_INCOMPAT_FILETYPE,
"filetype" },
{ E2P_FEATURE_INCOMPAT, EXT3_FEATURE_INCOMPAT_RECOVER,
"needs_recovery" },
{ E2P_FEATURE_INCOMPAT, EXT3_FEATURE_INCOMPAT_JOURNAL_DEV,
"journal_dev" },
{ E2P_FEATURE_INCOMPAT, EXT3_FEATURE_INCOMPAT_EXTENTS,
"extents" },
{ E2P_FEATURE_INCOMPAT, EXT2_FEATURE_INCOMPAT_META_BG,
"meta_bg" },
{ 0, 0, 0 },
};
const char *e2p_feature2string(int compat, unsigned int mask)
{
struct feature *f;
static char buf[20];
char fchar;
int fnum;
for (f = feature_list; f->string; f++) {
if ((compat == f->compat) &&
(mask == f->mask))
return f->string;
}
switch (compat) {
case E2P_FEATURE_COMPAT:
fchar = 'C';
break;
case E2P_FEATURE_INCOMPAT:
fchar = 'I';
break;
case E2P_FEATURE_RO_INCOMPAT:
fchar = 'R';
break;
default:
fchar = '?';
break;
}
for (fnum = 0; mask >>= 1; fnum++);
sprintf(buf, "FEATURE_%c%d", fchar, fnum);
return buf;
}
int e2p_string2feature(char *string, int *compat_type, unsigned int *mask)
{
struct feature *f;
char *eptr;
int num;
for (f = feature_list; f->string; f++) {
if (!strcasecmp(string, f->string)) {
*compat_type = f->compat;
*mask = f->mask;
return 0;
}
}
if (strncasecmp(string, "FEATURE_", 8))
return 1;
switch (string[8]) {
case 'c':
case 'C':
*compat_type = E2P_FEATURE_COMPAT;
break;
case 'i':
case 'I':
*compat_type = E2P_FEATURE_INCOMPAT;
break;
case 'r':
case 'R':
*compat_type = E2P_FEATURE_RO_INCOMPAT;
break;
default:
return 1;
}
if (string[9] == 0)
return 1;
num = strtol(string+9, &eptr, 10);
if (num > 32 || num < 0)
return 1;
if (*eptr)
return 1;
*mask = 1 << num;
return 0;
}
static inline char *skip_over_blanks(char *cp)
{
while (*cp && isspace(*cp))
cp++;
return cp;
}
static inline char *skip_over_word(char *cp)
{
while (*cp && !isspace(*cp) && *cp != ',')
cp++;
return cp;
}
/*
* Edit a feature set array as requested by the user. The ok_array,
* if set, allows the application to limit what features the user is
* allowed to set or clear using this function.
*/
int e2p_edit_feature(const char *str, __u32 *compat_array, __u32 *ok_array)
{
char *cp, *buf, *next;
int neg;
unsigned int mask;
int compat_type;
buf = xmalloc(strlen(str)+1);
strcpy(buf, str);
cp = buf;
while (cp && *cp) {
neg = 0;
cp = skip_over_blanks(cp);
next = skip_over_word(cp);
if (*next == 0)
next = 0;
else
*next = 0;
switch (*cp) {
case '-':
case '^':
neg++;
case '+':
cp++;
break;
}
if (e2p_string2feature(cp, &compat_type, &mask))
return 1;
if (ok_array && !(ok_array[compat_type] & mask))
return 1;
if (neg)
compat_array[compat_type] &= ~mask;
else
compat_array[compat_type] |= mask;
cp = next ? next+1 : 0;
}
return 0;
}