- 根目录:
- usr
- gen_init_cpio.c
#include <stdio.h>
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <string.h>
#include <unistd.h>
#include <time.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>
#include <limits.h>
/*
* Original work by Jeff Garzik
*
* External file lists, symlink, pipe and fifo support by Thayne Harbaugh
* Hard link support by Luciano Rocha
*/
#define xstr(s) #s
#define str(s) xstr(s)
static unsigned int offset;
static unsigned int ino = 721;
static time_t default_mtime;
struct file_handler {
const char *type;
int (*handler)(const char *line);
};
static void push_string(const char *name)
{
unsigned int name_len = strlen(name) + 1;
fputs(name, stdout);
putchar(0);
offset += name_len;
}
static void push_pad (void)
{
while (offset & 3) {
putchar(0);
offset++;
}
}
static void push_rest(const char *name)
{
unsigned int name_len = strlen(name) + 1;
unsigned int tmp_ofs;
fputs(name, stdout);
putchar(0);
offset += name_len;
tmp_ofs = name_len + 110;
while (tmp_ofs & 3) {
putchar(0);
offset++;
tmp_ofs++;
}
}
static void push_hdr(const char *s)
{
fputs(s, stdout);
offset += 110;
}
static void cpio_trailer(void)
{
char s[256];
const char name[] = "TRAILER!!!";
sprintf(s, "%s%08X%08X%08lX%08lX%08X%08lX"
"%08X%08X%08X%08X%08X%08X%08X",
"070701", /* magic */
0, /* ino */
0, /* mode */
(long) 0, /* uid */
(long) 0, /* gid */
1, /* nlink */
(long) 0, /* mtime */
0, /* filesize */
0, /* major */
0, /* minor */
0, /* rmajor */
0, /* rminor */
(unsigned)strlen(name)+1, /* namesize */
0); /* chksum */
push_hdr(s);
push_rest(name);
while (offset % 512) {
putchar(0);
offset++;
}
}
static int cpio_mkslink(const char *name, const char *target,
unsigned int mode, uid_t uid, gid_t gid)
{
char s[256];
if (name[0] == '/')
name++;
sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
"%08X%08X%08X%08X%08X%08X%08X",
"070701", /* magic */
ino++, /* ino */
S_IFLNK | mode, /* mode */
(long) uid, /* uid */
(long) gid, /* gid */
1, /* nlink */
(long) default_mtime, /* mtime */
(unsigned)strlen(target)+1, /* filesize */
3, /* major */
1, /* minor */
0, /* rmajor */
0, /* rminor */
(unsigned)strlen(name) + 1,/* namesize */
0); /* chksum */
push_hdr(s);
push_string(name);
push_pad();
push_string(target);
push_pad();
return 0;
}
static int cpio_mkslink_line(const char *line)
{
char name[PATH_MAX + 1];
char target[PATH_MAX + 1];
unsigned int mode;
int uid;
int gid;
int rc = -1;
if (5 != sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX) "s %o %d %d", name, target, &mode, &uid, &gid)) {
fprintf(stderr, "Unrecognized dir format '%s'", line);
goto fail;
}
rc = cpio_mkslink(name, target, mode, uid, gid);
fail:
return rc;
}
static int cpio_mkgeneric(const char *name, unsigned int mode,
uid_t uid, gid_t gid)
{
char s[256];
if (name[0] == '/')
name++;
sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
"%08X%08X%08X%08X%08X%08X%08X",
"070701", /* magic */
ino++, /* ino */
mode, /* mode */
(long) uid, /* uid */
(long) gid, /* gid */
2, /* nlink */
(long) default_mtime, /* mtime */
0, /* filesize */
3, /* major */
1, /* minor */
0, /* rmajor */
0, /* rminor */
(unsigned)strlen(name) + 1,/* namesize */
0); /* chksum */
push_hdr(s);
push_rest(name);
return 0;
}
enum generic_types {
GT_DIR,
GT_PIPE,
GT_SOCK
};
struct generic_type {
const char *type;
mode_t mode;
};
static struct generic_type generic_type_table[] = {
[GT_DIR] = {
.type = "dir",
.mode = S_IFDIR
},
[GT_PIPE] = {
.type = "pipe",
.mode = S_IFIFO
},
[GT_SOCK] = {
.type = "sock",
.mode = S_IFSOCK
}
};
static int cpio_mkgeneric_line(const char *line, enum generic_types gt)
{
char name[PATH_MAX + 1];
unsigned int mode;
int uid;
int gid;
int rc = -1;
if (4 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d", name, &mode, &uid, &gid)) {
fprintf(stderr, "Unrecognized %s format '%s'",
line, generic_type_table[gt].type);
goto fail;
}
mode |= generic_type_table[gt].mode;
rc = cpio_mkgeneric(name, mode, uid, gid);
fail:
return rc;
}
static int cpio_mkdir_line(const char *line)
{
return cpio_mkgeneric_line(line, GT_DIR);
}
static int cpio_mkpipe_line(const char *line)
{
return cpio_mkgeneric_line(line, GT_PIPE);
}
static int cpio_mksock_line(const char *line)
{
return cpio_mkgeneric_line(line, GT_SOCK);
}
static int cpio_mknod(const char *name, unsigned int mode,
uid_t uid, gid_t gid, char dev_type,
unsigned int maj, unsigned int min)
{
char s[256];
if (dev_type == 'b')
mode |= S_IFBLK;
else
mode |= S_IFCHR;
if (name[0] == '/')
name++;
sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
"%08X%08X%08X%08X%08X%08X%08X",
"070701", /* magic */
ino++, /* ino */
mode, /* mode */
(long) uid, /* uid */
(long) gid, /* gid */
1, /* nlink */
(long) default_mtime, /* mtime */
0, /* filesize */
3, /* major */
1, /* minor */
maj, /* rmajor */
min, /* rminor */
(unsigned)strlen(name) + 1,/* namesize */
0); /* chksum */
push_hdr(s);
push_rest(name);
return 0;
}
static int cpio_mknod_line(const char *line)
{
char name[PATH_MAX + 1];
unsigned int mode;
int uid;
int gid;
char dev_type;
unsigned int maj;
unsigned int min;
int rc = -1;
if (7 != sscanf(line, "%" str(PATH_MAX) "s %o %d %d %c %u %u",
name, &mode, &uid, &gid, &dev_type, &maj, &min)) {
fprintf(stderr, "Unrecognized nod format '%s'", line);
goto fail;
}
rc = cpio_mknod(name, mode, uid, gid, dev_type, maj, min);
fail:
return rc;
}
static int cpio_mkfile(const char *name, const char *location,
unsigned int mode, uid_t uid, gid_t gid,
unsigned int nlinks)
{
char s[256];
char *filebuf = NULL;
struct stat buf;
long size;
int file = -1;
int retval;
int rc = -1;
int namesize;
int i;
mode |= S_IFREG;
file = open (location, O_RDONLY);
if (file < 0) {
fprintf (stderr, "File %s could not be opened for reading\n", location);
goto error;
}
retval = fstat(file, &buf);
if (retval) {
fprintf(stderr, "File %s could not be stat()'ed\n", location);
goto error;
}
filebuf = malloc(buf.st_size);
if (!filebuf) {
fprintf (stderr, "out of memory\n");
goto error;
}
retval = read (file, filebuf, buf.st_size);
if (retval < 0) {
fprintf (stderr, "Can not read %s file\n", location);
goto error;
}
size = 0;
for (i = 1; i <= nlinks; i++) {
/* data goes on last link */
if (i == nlinks) size = buf.st_size;
if (name[0] == '/')
name++;
namesize = strlen(name) + 1;
sprintf(s,"%s%08X%08X%08lX%08lX%08X%08lX"
"%08lX%08X%08X%08X%08X%08X%08X",
"070701", /* magic */
ino, /* ino */
mode, /* mode */
(long) uid, /* uid */
(long) gid, /* gid */
nlinks, /* nlink */
(long) buf.st_mtime, /* mtime */
size, /* filesize */
3, /* major */
1, /* minor */
0, /* rmajor */
0, /* rminor */
namesize, /* namesize */
0); /* chksum */
push_hdr(s);
push_string(name);
push_pad();
if (size) {
if (fwrite(filebuf, size, 1, stdout) != 1) {
fprintf(stderr, "writing filebuf failed\n");
goto error;
}
offset += size;
push_pad();
}
name += namesize;
}
ino++;
rc = 0;
error:
if (filebuf) free(filebuf);
if (file >= 0) close(file);
return rc;
}
static char *cpio_replace_env(char *new_location)
{
char expanded[PATH_MAX + 1];
char env_var[PATH_MAX + 1];
char *start;
char *end;
for (start = NULL; (start = strstr(new_location, "${")); ) {
end = strchr(start, '}');
if (start < end) {
*env_var = *expanded = '\0';
strncat(env_var, start + 2, end - start - 2);
strncat(expanded, new_location, start - new_location);
strncat(expanded, getenv(env_var), PATH_MAX);
strncat(expanded, end + 1, PATH_MAX);
strncpy(new_location, expanded, PATH_MAX);
} else
break;
}
return new_location;
}
static int cpio_mkfile_line(const char *line)
{
char name[PATH_MAX + 1];
char *dname = NULL; /* malloc'ed buffer for hard links */
char location[PATH_MAX + 1];
unsigned int mode;
int uid;
int gid;
int nlinks = 1;
int end = 0, dname_len = 0;
int rc = -1;
if (5 > sscanf(line, "%" str(PATH_MAX) "s %" str(PATH_MAX)
"s %o %d %d %n",
name, location, &mode, &uid, &gid, &end)) {
fprintf(stderr, "Unrecognized file format '%s'", line);
goto fail;
}
if (end && isgraph(line[end])) {
int len;
int nend;
dname = malloc(strlen(line));
if (!dname) {
fprintf (stderr, "out of memory (%d)\n", dname_len);
goto fail;
}
dname_len = strlen(name) + 1;
memcpy(dname, name, dname_len);
do {
nend = 0;
if (sscanf(line + end, "%" str(PATH_MAX) "s %n",
name, &nend) < 1)
break;
len = strlen(name) + 1;
memcpy(dname + dname_len, name, len);
dname_len += len;
nlinks++;
end += nend;
} while (isgraph(line[end]));
} else {
dname = name;
}
rc = cpio_mkfile(dname, cpio_replace_env(location),
mode, uid, gid, nlinks);
fail:
if (dname_len) free(dname);
return rc;
}
static void usage(const char *prog)
{
fprintf(stderr, "Usage:\n"
"\t%s [-t <timestamp>] <cpio_list>\n"
"\n"
"<cpio_list> is a file containing newline separated entries that\n"
"describe the files to be included in the initramfs archive:\n"
"\n"
"# a comment\n"
"file <name> <location> <mode> <uid> <gid> [<hard links>]\n"
"dir <name> <mode> <uid> <gid>\n"
"nod <name> <mode> <uid> <gid> <dev_type> <maj> <min>\n"
"slink <name> <target> <mode> <uid> <gid>\n"
"pipe <name> <mode> <uid> <gid>\n"
"sock <name> <mode> <uid> <gid>\n"
"\n"
"<name> name of the file/dir/nod/etc in the archive\n"
"<location> location of the file in the current filesystem\n"
" expands shell variables quoted with ${}\n"
"<target> link target\n"
"<mode> mode/permissions of the file\n"
"<uid> user id (0=root)\n"
"<gid> group id (0=root)\n"
"<dev_type> device type (b=block, c=character)\n"
"<maj> major number of nod\n"
"<min> minor number of nod\n"
"<hard links> space separated list of other links to file\n"
"\n"
"example:\n"
"# A simple initramfs\n"
"dir /dev 0755 0 0\n"
"nod /dev/console 0600 0 0 c 5 1\n"
"dir /root 0700 0 0\n"
"dir /sbin 0755 0 0\n"
"file /sbin/kinit /usr/src/klibc/kinit/kinit 0755 0 0\n"
"\n"
"<timestamp> is time in seconds since Epoch that will be used\n"
"as mtime for symlinks, special files and directories. The default\n"
"is to use the current time for these entries.\n",
prog);
}
struct file_handler file_handler_table[] = {
{
.type = "file",
.handler = cpio_mkfile_line,
}, {
.type = "nod",
.handler = cpio_mknod_line,
}, {
.type = "dir",
.handler = cpio_mkdir_line,
}, {
.type = "slink",
.handler = cpio_mkslink_line,
}, {
.type = "pipe",
.handler = cpio_mkpipe_line,
}, {
.type = "sock",
.handler = cpio_mksock_line,
}, {
.type = NULL,
.handler = NULL,
}
};
#define LINE_SIZE (2 * PATH_MAX + 50)
int main (int argc, char *argv[])
{
FILE *cpio_list;
char line[LINE_SIZE];
char *args, *type;
int ec = 0;
int line_nr = 0;
const char *filename;
default_mtime = time(NULL);
while (1) {
int opt = getopt(argc, argv, "t:h");
char *invalid;
if (opt == -1)
break;
switch (opt) {
case 't':
default_mtime = strtol(optarg, &invalid, 10);
if (!*optarg || *invalid) {
fprintf(stderr, "Invalid timestamp: %s\n",
optarg);
usage(argv[0]);
exit(1);
}
break;
case 'h':
case '?':
usage(argv[0]);
exit(opt == 'h' ? 0 : 1);
}
}
if (argc - optind != 1) {
usage(argv[0]);
exit(1);
}
filename = argv[optind];
if (!strcmp(filename, "-"))
cpio_list = stdin;
else if (!(cpio_list = fopen(filename, "r"))) {
fprintf(stderr, "ERROR: unable to open '%s': %s\n\n",
filename, strerror(errno));
usage(argv[0]);
exit(1);
}
while (fgets(line, LINE_SIZE, cpio_list)) {
int type_idx;
size_t slen = strlen(line);
line_nr++;
if ('#' == *line) {
/* comment - skip to next line */
continue;
}
if (! (type = strtok(line, " \t"))) {
fprintf(stderr,
"ERROR: incorrect format, could not locate file type line %d: '%s'\n",
line_nr, line);
ec = -1;
break;
}
if ('\n' == *type) {
/* a blank line */
continue;
}
if (slen == strlen(type)) {
/* must be an empty line */
continue;
}
if (! (args = strtok(NULL, "\n"))) {
fprintf(stderr,
"ERROR: incorrect format, newline required line %d: '%s'\n",
line_nr, line);
ec = -1;
}
for (type_idx = 0; file_handler_table[type_idx].type; type_idx++) {
int rc;
if (! strcmp(line, file_handler_table[type_idx].type)) {
if ((rc = file_handler_table[type_idx].handler(args))) {
ec = rc;
fprintf(stderr, " line %d\n", line_nr);
}
break;
}
}
if (NULL == file_handler_table[type_idx].type) {
fprintf(stderr, "unknown file type line %d: '%s'\n",
line_nr, line);
}
}
if (ec == 0)
cpio_trailer();
exit(ec);
}