Add a standalone makedevs application to be used along with

fakeroot to construct target device nodes for filesystems
and utilities (such as tar) that do not currently support
device tables natively.
This commit is contained in:
Eric Andersen 2005-06-09 11:11:10 +00:00
parent 246d05c718
commit 611ec0e3b1
2 changed files with 506 additions and 0 deletions

479
target/makedevs/makedevs.c Normal file
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/* vi: set sw=4 ts=4: */
/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This program 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 Library General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
*/
#define _GNU_SOURCE
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <getopt.h>
#include <time.h>
#include <pwd.h>
#include <grp.h>
#include <unistd.h>
#include <errno.h>
#include <stdarg.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/sysmacros.h> /* major() and minor() */
const char *bb_applet_name;
void bb_verror_msg(const char *s, va_list p)
{
fflush(stdout);
fprintf(stderr, "%s: ", bb_applet_name);
vfprintf(stderr, s, p);
}
void bb_error_msg(const char *s, ...)
{
va_list p;
va_start(p, s);
bb_verror_msg(s, p);
va_end(p);
putc('\n', stderr);
}
void bb_error_msg_and_die(const char *s, ...)
{
va_list p;
va_start(p, s);
bb_verror_msg(s, p);
va_end(p);
putc('\n', stderr);
exit(1);
}
void bb_vperror_msg(const char *s, va_list p)
{
int err=errno;
if(s == 0) s = "";
bb_verror_msg(s, p);
if (*s) s = ": ";
fprintf(stderr, "%s%s\n", s, strerror(err));
}
void bb_perror_msg(const char *s, ...)
{
va_list p;
va_start(p, s);
bb_vperror_msg(s, p);
va_end(p);
}
void bb_perror_msg_and_die(const char *s, ...)
{
va_list p;
va_start(p, s);
bb_vperror_msg(s, p);
va_end(p);
exit(1);
}
FILE *bb_xfopen(const char *path, const char *mode)
{
FILE *fp;
if ((fp = fopen(path, mode)) == NULL)
bb_perror_msg_and_die("%s", path);
return fp;
}
int bb_make_directory (char *path, long mode, int flags)
{
mode_t mask;
const char *fail_msg;
char *s = path;
char c;
struct stat st;
enum {
FILEUTILS_PRESERVE_STATUS = 1,
FILEUTILS_DEREFERENCE = 2,
FILEUTILS_RECUR = 4,
FILEUTILS_FORCE = 8,
FILEUTILS_INTERACTIVE = 16
};
mask = umask(0);
if (mode == -1) {
umask(mask);
mode = (S_IXUSR | S_IXGRP | S_IXOTH |
S_IWUSR | S_IWGRP | S_IWOTH |
S_IRUSR | S_IRGRP | S_IROTH) & ~mask;
} else {
umask(mask & ~0300);
}
do {
c = 0;
if (flags & FILEUTILS_RECUR) { /* Get the parent. */
/* Bypass leading non-'/'s and then subsequent '/'s. */
while (*s) {
if (*s == '/') {
do {
++s;
} while (*s == '/');
c = *s; /* Save the current char */
*s = 0; /* and replace it with nul. */
break;
}
++s;
}
}
if (mkdir(path, 0777) < 0) {
/* If we failed for any other reason than the directory
* already exists, output a diagnostic and return -1.*/
if (errno != EEXIST
|| !(flags & FILEUTILS_RECUR)
|| (stat(path, &st) < 0 || !S_ISDIR(st.st_mode))) {
fail_msg = "create";
umask(mask);
break;
}
/* Since the directory exists, don't attempt to change
* permissions if it was the full target. Note that
* this is not an error conditon. */
if (!c) {
umask(mask);
return 0;
}
}
if (!c) {
/* Done. If necessary, updated perms on the newly
* created directory. Failure to update here _is_
* an error.*/
umask(mask);
if ((mode != -1) && (chmod(path, mode) < 0)){
fail_msg = "set permissions of";
break;
}
return 0;
}
/* Remove any inserted nul from the path (recursive mode). */
*s = c;
} while (1);
bb_perror_msg ("Cannot %s directory `%s'", fail_msg, path);
return -1;
}
const char * const bb_msg_memory_exhausted = "memory exhausted";
void *xmalloc(size_t size)
{
void *ptr = malloc(size);
if (ptr == NULL && size != 0)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return ptr;
}
void *xcalloc(size_t nmemb, size_t size)
{
void *ptr = calloc(nmemb, size);
if (ptr == NULL && nmemb != 0 && size != 0)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return ptr;
}
void *xrealloc(void *ptr, size_t size)
{
ptr = realloc(ptr, size);
if (ptr == NULL && size != 0)
bb_error_msg_and_die(bb_msg_memory_exhausted);
return ptr;
}
char *private_get_line_from_file(FILE *file, int c)
{
#define GROWBY (80) /* how large we will grow strings by */
int ch;
int idx = 0;
char *linebuf = NULL;
int linebufsz = 0;
while ((ch = getc(file)) != EOF) {
/* grow the line buffer as necessary */
if (idx > linebufsz - 2) {
linebuf = xrealloc(linebuf, linebufsz += GROWBY);
}
linebuf[idx++] = (char)ch;
if (!ch) return linebuf;
if (c<2 && ch == '\n') {
if (c) {
--idx;
}
break;
}
}
if (linebuf) {
if (ferror(file)) {
free(linebuf);
return NULL;
}
linebuf[idx] = 0;
}
return linebuf;
}
char *bb_get_chomped_line_from_file(FILE *file)
{
return private_get_line_from_file(file, 1);
}
long my_getpwnam(const char *name)
{
struct passwd *myuser;
myuser = getpwnam(name);
if (myuser==NULL)
bb_error_msg_and_die("unknown user name: %s", name);
return myuser->pw_uid;
}
long my_getgrnam(const char *name)
{
struct group *mygroup;
mygroup = getgrnam(name);
if (mygroup==NULL)
bb_error_msg_and_die("unknown group name: %s", name);
return (mygroup->gr_gid);
}
unsigned long get_ug_id(const char *s, long (*my_getxxnam)(const char *))
{
unsigned long r;
char *p;
r = strtoul(s, &p, 10);
if (*p || (s == p)) {
r = my_getxxnam(s);
}
return r;
}
char * last_char_is(const char *s, int c)
{
char *sret = (char *)s;
if (sret) {
sret = strrchr(sret, c);
if(sret != NULL && *(sret+1) != 0)
sret = NULL;
}
return sret;
}
void bb_xasprintf(char **string_ptr, const char *format, ...)
{
va_list p;
int r;
va_start(p, format);
r = vasprintf(string_ptr, format, p);
va_end(p);
if (r < 0) {
bb_perror_msg_and_die("bb_xasprintf");
}
}
char *concat_path_file(const char *path, const char *filename)
{
char *outbuf;
char *lc;
if (!path)
path = "";
lc = last_char_is(path, '/');
while (*filename == '/')
filename++;
bb_xasprintf(&outbuf, "%s%s%s", path, (lc==NULL ? "/" : ""), filename);
return outbuf;
}
int main(int argc, char **argv)
{
int opt;
FILE *table = stdin;
char *rootdir = "./";
char *line;
int ret = EXIT_SUCCESS;
bb_applet_name = argv[0];
while ((opt = getopt(argc, argv, "d:r:")) != -1) {
switch(opt) {
case 'd':
table = bb_xfopen(optarg, "r");
break;
case 'n':
rootdir = optarg;
break;
default:
fprintf(stderr, "%s: [-r rootdir] [device_table]\n\n", bb_applet_name);
fprintf(stderr, "Creates a batch of special files as specified in a device table.\n");
fprintf(stderr, "Device table entries take the form of:\n");
fprintf(stderr, "type mode user group major minor start increment count\n\n");
fprintf(stderr, "Where name is the file name, type can be one of:\n");
fprintf(stderr, " f A regular file\n");
fprintf(stderr, " d Directory\n");
fprintf(stderr, " c Character special device file\n");
fprintf(stderr, " b Block special device file\n");
fprintf(stderr, " p Fifo (named pipe)\n");
fprintf(stderr, "uid is the user id for the target file, gid is the group id for the\n");
fprintf(stderr, "target file. The rest of the entries (major, minor, etc) apply to\n");
fprintf(stderr, "to device special files. A '-' may be used for blank entries.\n\n");
fprintf(stderr, "For example:\n");
fprintf(stderr, "<name> <type> <mode> <uid> <gid> <major> <minor> <start> <inc> <count>\n");
fprintf(stderr, "/dev d 755 0 0 - - - - -\n");
fprintf(stderr, "/dev/console c 666 0 0 5 1 - - -\n");
fprintf(stderr, "/dev/null c 666 0 0 1 3 0 0 -\n");
fprintf(stderr, "/dev/zero c 666 0 0 1 5 0 0 -\n");
fprintf(stderr, "/dev/hda b 640 0 0 3 0 0 0 -\n");
fprintf(stderr, "/dev/hda b 640 0 0 3 1 1 1 15\n\n");
fprintf(stderr, "Will Produce:\n");
fprintf(stderr, "/dev\n");
fprintf(stderr, "/dev/console\n");
fprintf(stderr, "/dev/null\n");
fprintf(stderr, "/dev/zero\n");
fprintf(stderr, "/dev/hda\n");
fprintf(stderr, "/dev/hda[0-15]\n");
exit(1);
}
}
if (chdir(rootdir) == -1) {
bb_perror_msg_and_die("Couldnt chdir to %s", rootdir);
}
umask(0);
while ((line = bb_get_chomped_line_from_file(table))) {
char type;
unsigned int mode = 0755;
unsigned int major = 0;
unsigned int minor = 0;
unsigned int count = 0;
unsigned int increment = 0;
unsigned int start = 0;
char name[41];
char user[41];
char group[41];
char *full_name;
uid_t uid;
gid_t gid;
if ((2 > sscanf(line, "%40s %c %o %40s %40s %u %u %u %u %u", name,
&type, &mode, user, group, &major,
&minor, &start, &increment, &count)) ||
((major | minor | start | count | increment) > 255)) {
bb_error_msg("Ignoring invalid line\n%s\n", line);
ret = EXIT_FAILURE;
continue;
}
if (name[0] == '#') {
continue;
}
if (group) {
gid = get_ug_id(group, my_getgrnam);
} else {
gid = getgid();
}
if (user) {
uid = get_ug_id(user, my_getpwnam);
} else {
uid = getuid();
}
full_name = concat_path_file(rootdir, name);
if (type == 'd') {
bb_make_directory(full_name, mode | S_IFDIR, 0);
if (chown(full_name, uid, gid) == -1) {
bb_perror_msg("chown failed for %s", full_name);
ret = EXIT_FAILURE;
goto loop;
}
} else {
dev_t rdev;
if (type == 'p') {
mode |= S_IFIFO;
}
else if (type == 'c') {
mode |= S_IFCHR;
}
else if (type == 'b') {
mode |= S_IFBLK;
} else {
bb_error_msg("Unsupported file type %c", type);
ret = EXIT_FAILURE;
goto loop;
}
if (count > 0) {
int i;
char *full_name_inc;
full_name_inc = xmalloc(strlen(full_name) + 4);
for (i = start; i < count; i++) {
sprintf(full_name_inc, "%s%d", full_name, i);
rdev = (major << 8) + minor + (i * increment - start);
if (mknod(full_name_inc, mode, rdev) == -1) {
bb_perror_msg("Couldnt create node %s", full_name_inc);
ret = EXIT_FAILURE;
}
else if (chown(full_name_inc, uid, gid) == -1) {
bb_perror_msg("chown failed for %s", full_name_inc);
ret = EXIT_FAILURE;
}
}
free(full_name_inc);
} else {
rdev = (major << 8) + minor;
if (mknod(full_name, mode, rdev) == -1) {
bb_perror_msg("Couldnt create node %s", full_name);
ret = EXIT_FAILURE;
}
else if (chown(full_name, uid, gid) == -1) {
bb_perror_msg("chown failed for %s", full_name);
ret = EXIT_FAILURE;
}
}
}
loop:
free(line);
free(full_name);
}
fclose(table);
return 0;
}

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#############################################################
#
# build makedevs to run on the build system, in order to create
# device nodes and whatnot for the target device, in conjunction
# with fakeroot.
#
#############################################################
MAKEDEVS_DIR=$(BUILD_DIR)/makedevs
$(MAKEDEVS_DIR)/makedevs.c:
mkdir $(MAKEDEVS_DIR)
cp target/makedevs/makedevs.c $(MAKEDEVS_DIR)
$(MAKEDEVS_DIR)/makedevs: $(MAKEDEVS_DIR)
gcc -Wall -O2 makedevs.c -o makedevs
touch -c $(MAKEDEVS_DIR)/makedevs
makedevs: $(MAKEDEVS_DIR)/makedevs
makedevs-source:
makedevs-clean:
-rm -rf $(MAKEDEVS_DIR)
makedevs-dirclean:
rm -rf $(MAKEDEVS_DIR)