hush/e2fsprogs/chattr.c
Denis Vlasenko 6ca409e0e4 trylink: produce even more info about final link stage
trylink: explain how to modify link and drastically decrease amount
  of padding (unfortunately, needs hand editing ATM).
*: add ALIGN1 / ALIGN2 to global strings and arrays of bytes and shorts

size saving: 0.5k
2007-08-12 20:58:27 +00:00

191 lines
4.5 KiB
C

/* vi: set sw=4 ts=4: */
/*
* chattr.c - Change file attributes on an ext2 file system
*
* Copyright (C) 1993, 1994 Remy Card <card@masi.ibp.fr>
* Laboratoire MASI, Institut Blaise Pascal
* Universite Pierre et Marie Curie (Paris VI)
*
* This file can be redistributed under the terms of the GNU General
* Public License
*/
/*
* History:
* 93/10/30 - Creation
* 93/11/13 - Replace stat() calls by lstat() to avoid loops
* 94/02/27 - Integrated in Ted's distribution
* 98/12/29 - Ignore symlinks when working recursively (G M Sipe)
* 98/12/29 - Display version info only when -V specified (G M Sipe)
*/
#include "libbb.h"
#include "e2fs_lib.h"
#define OPT_ADD 1
#define OPT_REM 2
#define OPT_SET 4
#define OPT_SET_VER 8
struct globals {
unsigned long version;
unsigned long af;
unsigned long rf;
smallint flags;
smallint recursive;
};
static unsigned long get_flag(char c)
{
/* Two separate vectors take less space than vector of structs */
static const char flags_letter[] ALIGN1 = "ASDacdijsutT";
static const unsigned long flags_val[] = {
/* A */ EXT2_NOATIME_FL,
/* S */ EXT2_SYNC_FL,
/* D */ EXT2_DIRSYNC_FL,
/* a */ EXT2_APPEND_FL,
/* c */ EXT2_COMPR_FL,
/* d */ EXT2_NODUMP_FL,
/* i */ EXT2_IMMUTABLE_FL,
/* j */ EXT3_JOURNAL_DATA_FL,
/* s */ EXT2_SECRM_FL,
/* u */ EXT2_UNRM_FL,
/* t */ EXT2_NOTAIL_FL,
/* T */ EXT2_TOPDIR_FL,
};
const char *fp;
for (fp = flags_letter; *fp; fp++)
if (*fp == c)
return flags_val[fp - flags_letter];
bb_show_usage();
}
static int decode_arg(const char *arg, struct globals *gp)
{
unsigned long *fl;
char opt = *arg++;
fl = &gp->af;
if (opt == '-') {
gp->flags |= OPT_REM;
fl = &gp->rf;
} else if (opt == '+') {
gp->flags |= OPT_ADD;
} else if (opt == '=') {
gp->flags |= OPT_SET;
} else
return 0;
while (*arg)
*fl |= get_flag(*arg++);
return 1;
}
static void change_attributes(const char *name, struct globals *gp);
static int chattr_dir_proc(const char *dir_name, struct dirent *de, void *gp)
{
char *path = concat_subpath_file(dir_name, de->d_name);
/* path is NULL if de->d_name is "." or "..", else... */
if (path) {
change_attributes(path, gp);
free(path);
}
return 0;
}
static void change_attributes(const char *name, struct globals *gp)
{
unsigned long fsflags;
struct stat st;
if (lstat(name, &st) != 0) {
bb_perror_msg("stat %s", name);
return;
}
if (S_ISLNK(st.st_mode) && gp->recursive)
return;
/* Don't try to open device files, fifos etc. We probably
* ought to display an error if the file was explicitly given
* on the command line (whether or not recursive was
* requested). */
if (!S_ISREG(st.st_mode) && !S_ISLNK(st.st_mode) && !S_ISDIR(st.st_mode))
return;
if (gp->flags & OPT_SET_VER)
if (fsetversion(name, gp->version) != 0)
bb_perror_msg("setting version on %s", name);
if (gp->flags & OPT_SET) {
fsflags = gp->af;
} else {
if (fgetflags(name, &fsflags) != 0) {
bb_perror_msg("reading flags on %s", name);
goto skip_setflags;
}
/*if (gp->flags & OPT_REM) - not needed, rf is zero otherwise */
fsflags &= ~gp->rf;
/*if (gp->flags & OPT_ADD) - not needed, af is zero otherwise */
fsflags |= gp->af;
/* What is this? And why it's not done for SET case? */
if (!S_ISDIR(st.st_mode))
fsflags &= ~EXT2_DIRSYNC_FL;
}
if (fsetflags(name, fsflags) != 0)
bb_perror_msg("setting flags on %s", name);
skip_setflags:
if (gp->recursive && S_ISDIR(st.st_mode))
iterate_on_dir(name, chattr_dir_proc, gp);
}
int chattr_main(int argc, char **argv);
int chattr_main(int argc, char **argv)
{
struct globals g;
char *arg;
memset(&g, 0, sizeof(g));
/* parse the args */
while ((arg = *++argv)) {
/* take care of -R and -v <version> */
if (arg[0] == '-'
&& (arg[1] == 'R' || arg[1] == 'v')
&& !arg[2]
) {
if (arg[1] == 'R') {
g.recursive = 1;
continue;
}
/* arg[1] == 'v' */
if (!*++argv)
bb_show_usage();
g.version = xatoul(*argv);
g.flags |= OPT_SET_VER;
continue;
}
if (!decode_arg(arg, &g))
break;
}
/* run sanity checks on all the arguments given us */
if (!*argv)
bb_show_usage();
if ((g.flags & OPT_SET) && (g.flags & (OPT_ADD|OPT_REM)))
bb_error_msg_and_die("= is incompatible with - and +");
if (g.rf & g.af)
bb_error_msg_and_die("can't set and unset a flag");
if (!g.flags)
bb_error_msg_and_die("must use '-v', =, - or +");
/* now run chattr on all the files passed to us */
do change_attributes(*argv, &g); while (*++argv);
return EXIT_SUCCESS;
}