M7350/oe-core/meta/recipes-devtools/makedevs/makedevs-1.0.0/makedevs.c
2024-09-09 08:52:07 +00:00

361 lines
8.4 KiB
C

#define _GNU_SOURCE
#include <stdio.h>
#include <errno.h>
#include <string.h>
#include <stdarg.h>
#include <stdlib.h>
#include <ctype.h>
#include <fcntl.h>
#include <dirent.h>
#include <unistd.h>
#include <time.h>
#include <getopt.h>
#include <libgen.h>
#include <sys/types.h>
#include <sys/stat.h>
#define MINORBITS 8
#define MKDEV(ma,mi) (((ma) << MINORBITS) | (mi))
/* These are all stolen from busybox's libbb to make
* error handling simpler (and since I maintain busybox,
* I'm rather partial to these for error handling).
* -Erik
*/
static const char *const app_name = "makedevs";
static const char *const memory_exhausted = "memory exhausted";
static char default_rootdir[]=".";
static char *rootdir = default_rootdir;
static void verror_msg(const char *s, va_list p)
{
fflush(stdout);
fprintf(stderr, "%s: ", app_name);
vfprintf(stderr, s, p);
}
static void error_msg_and_die(const char *s, ...)
{
va_list p;
va_start(p, s);
verror_msg(s, p);
va_end(p);
putc('\n', stderr);
exit(EXIT_FAILURE);
}
static void vperror_msg(const char *s, va_list p)
{
int err = errno;
if (s == 0)
s = "";
verror_msg(s, p);
if (*s)
s = ": ";
fprintf(stderr, "%s%s\n", s, strerror(err));
}
#if 0
static void perror_msg(const char *s, ...)
{
va_list p;
va_start(p, s);
vperror_msg(s, p);
va_end(p);
}
#endif
static void perror_msg_and_die(const char *s, ...)
{
va_list p;
va_start(p, s);
vperror_msg(s, p);
va_end(p);
exit(EXIT_FAILURE);
}
static FILE *xfopen(const char *path, const char *mode)
{
FILE *fp;
if ((fp = fopen(path, mode)) == NULL)
perror_msg_and_die("%s", path);
return fp;
}
static char *xstrdup(const char *s)
{
char *t;
if (s == NULL)
return NULL;
t = strdup(s);
if (t == NULL)
error_msg_and_die(memory_exhausted);
return t;
}
static void add_new_directory(char *name, char *path,
unsigned long uid, unsigned long gid, unsigned long mode)
{
mkdir(path, mode);
chown(path, uid, gid);
// printf("Directory: %s %s UID: %ld GID %ld MODE: %ld\n", path, name, uid, gid, mode);
}
static void add_new_device(char *name, char *path, unsigned long uid,
unsigned long gid, unsigned long mode, dev_t rdev)
{
int status;
struct stat sb;
time_t timestamp = time(NULL);
memset(&sb, 0, sizeof(struct stat));
status = lstat(path, &sb);
if (status >= 0) {
/* It is ok for some types of files to not exit on disk (such as
* device nodes), but if they _do_ exist the specified mode had
* better match the actual file or strange things will happen.... */
if ((mode & S_IFMT) != (sb.st_mode & S_IFMT))
error_msg_and_die("%s: file type does not match specified type!", path);
timestamp = sb.st_mtime;
}
mknod(name, mode, rdev);
chown(path, uid, gid);
// printf("Device: %s %s UID: %ld GID: %ld MODE: %ld MAJOR: %d MINOR: %d\n",
// path, name, uid, gid, mode, (short)(rdev >> 8), (short)(rdev & 0xff));
}
static void add_new_file(char *name, char *path, unsigned long uid,
unsigned long gid, unsigned long mode)
{
int fd = open(path,O_CREAT | O_WRONLY, mode);
if (fd < 0) {
error_msg_and_die("%s: file can not be created!", path);
} else {
close(fd);
}
chmod(path, mode);
chown(path, uid, gid);
// printf("File: %s %s UID: %ld GID: %ld MODE: %ld\n",
// path, name, gid, uid, mode);
}
static void add_new_fifo(char *name, char *path, unsigned long uid,
unsigned long gid, unsigned long mode)
{
if (mknod(path, mode, 0))
error_msg_and_die("%s: file can not be created with mknod!", path);
chown(path, uid, gid);
// printf("File: %s %s UID: %ld GID: %ld MODE: %ld\n",
// path, name, gid, uid, mode);
}
/* device table entries take the form of:
<path> <type> <mode> <uid> <gid> <major> <minor> <start> <inc> <count>
/dev/mem c 640 0 0 1 1 0 0 -
type can be one of:
f A regular file
d Directory
c Character special device file
b Block special device file
p Fifo (named pipe)
I don't bother with symlinks (permissions are irrelevant), hard
links (special cases of regular files), or sockets (why bother).
Regular files must exist in the target root directory. If a char,
block, fifo, or directory does not exist, it will be created.
*/
static int interpret_table_entry(char *line)
{
char *name;
char path[4096], type;
unsigned long mode = 0755, uid = 0, gid = 0, major = 0, minor = 0;
unsigned long start = 0, increment = 1, count = 0;
if (0 > sscanf(line, "%40s %c %lo %lu %lu %lu %lu %lu %lu %lu", path,
&type, &mode, &uid, &gid, &major, &minor, &start,
&increment, &count))
{
return 1;
}
if (!strcmp(path, "/")) {
error_msg_and_die("Device table entries require absolute paths");
}
name = xstrdup(path + 1);
sprintf(path, "%s/%s\0", rootdir, name);
switch (type) {
case 'd':
mode |= S_IFDIR;
add_new_directory(name, path, uid, gid, mode);
break;
case 'f':
mode |= S_IFREG;
add_new_file(name, path, uid, gid, mode);
break;
case 'p':
mode |= S_IFIFO;
add_new_fifo(name, path, uid, gid, mode);
break;
case 'c':
case 'b':
mode |= (type == 'c') ? S_IFCHR : S_IFBLK;
if (count > 0) {
int i;
dev_t rdev;
char buf[80];
for (i = start; i < count; i++) {
sprintf(buf, "%s%d", name, i);
/* FIXME: MKDEV uses illicit insider knowledge of kernel
* major/minor representation... */
rdev = MKDEV(major, minor + (i * increment - start));
add_new_device(buf, path, uid, gid, mode, rdev);
}
} else {
/* FIXME: MKDEV uses illicit insider knowledge of kernel
* major/minor representation... */
dev_t rdev = MKDEV(major, minor);
add_new_device(name, path, uid, gid, mode, rdev);
}
break;
default:
error_msg_and_die("Unsupported file type");
}
if (name) free(name);
return 0;
}
static void parse_device_table(FILE * file)
{
char *line;
size_t length = 256;
int len = 0;
/* Looks ok so far. The general plan now is to read in one
* line at a time, check for leading comment delimiters ('#'),
* then try and parse the line as a device table. If we fail
* to parse things, try and help the poor fool to fix their
* device table with a useful error msg... */
if((line = (char *)malloc(length)) == NULL) {
fclose(file);
return;
}
while ((len = getline(&line, &length, file)) != -1) {
/* First trim off any whitespace */
/* trim trailing whitespace */
while (len > 0 && isspace(line[len - 1]))
line[--len] = '\0';
/* trim leading whitespace */
memmove(line, &line[strspn(line, " \n\r\t\v")], len + 1);
/* If this is NOT a comment line, try to interpret it */
if (*line != '#') interpret_table_entry(line);
}
if (line) free(line);
fclose(file);
}
static int go(char *dname, FILE * devtable)
{
struct stat sb;
if (lstat(dname, &sb)) {
perror_msg_and_die("%s", dname);
}
if (chdir(dname))
perror_msg_and_die("%s", dname);
if (devtable)
parse_device_table(devtable);
return 0;
}
static struct option long_options[] = {
{"root", 1, NULL, 'r'},
{"help", 0, NULL, 'h'},
{"squash", 0, NULL, 'q'},
{"version", 0, NULL, 'v'},
{"devtable", 1, NULL, 'D'},
{NULL, 0, NULL, 0}
};
static char *helptext =
"Usage: makedevs [OPTIONS]\n"
"Build entries based upon device_table.txt\n\n"
"Options:\n"
" -r, -d, --root=DIR Build filesystem from directory DIR (default: cwd)\n"
" -D, --devtable=FILE Use the named FILE as a device table file\n"
" -q, --squash Squash permissions and owners making all files be owned by root\n"
" -h, --help Display this help text\n"
" -v, --version Display version information\n\n";
static char *revtext = "$Revision: 0.1 $";
int main(int argc, char **argv)
{
int c, opt;
extern char *optarg;
struct stat statbuf;
FILE *devtable = NULL;
umask (0);
while ((opt = getopt_long(argc, argv, "D:d:r:qhv",
long_options, &c)) >= 0) {
switch (opt) {
case 'D':
devtable = xfopen(optarg, "r");
if (fstat(fileno(devtable), &statbuf) < 0)
perror_msg_and_die(optarg);
if (statbuf.st_size < 10)
error_msg_and_die("%s: not a proper device table file", optarg);
break;
case 'h':
fprintf(stderr, helptext);
exit(1);
case 'r':
case 'd': /* for compatibility with mkfs.jffs, genext2fs, etc... */
if (rootdir != default_rootdir) {
error_msg_and_die("root directory specified more than once");
}
rootdir = xstrdup(optarg);
break;
case 'v':
fprintf(stderr, "makedevs revision %.*s\n",
(int) strlen(revtext) - 13, revtext + 11);
exit(1);
}
}
go(rootdir, devtable);
return 0;
}