#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <ctype.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <dirent.h>
#include <stdarg.h>
#include <fcntl.h>
#include <private/android_filesystem_config.h>
/* NOTES
**
** - see buffer-format.txt from the linux kernel docs for
** an explanation of this file format
** - dotfiles are ignored
** - directories named 'root' are ignored
** - device notes, pipes, etc are not supported (error)
*/
void die(const char *why, ...)
{
va_list ap;
va_start(ap, why);
fprintf(stderr,"error: ");
vfprintf(stderr, why, ap);
fprintf(stderr,"\n");
va_end(ap);
exit(1);
}
struct fs_config_entry {
char* name;
int uid, gid, mode;
};
static struct fs_config_entry* canned_config = NULL;
static char *target_out_path = NULL;
/* Each line in the canned file should be a path plus three ints (uid,
* gid, mode). */
#ifdef PATH_MAX
#define CANNED_LINE_LENGTH (PATH_MAX+100)
#else
#define CANNED_LINE_LENGTH (1024)
#endif
#define TRAILER "TRAILER!!!"
static int verbose = 0;
static int total_size = 0;
static void fix_stat(const char *path, struct stat *s)
{
uint64_t capabilities;
if (canned_config) {
// Use the list of file uid/gid/modes loaded from the file
// given with -f.
struct fs_config_entry* empty_path_config = NULL;
struct fs_config_entry* p;
for (p = canned_config; p->name; ++p) {
if (!p->name[0]) {
empty_path_config = p;
}
if (strcmp(p->name, path) == 0) {
s->st_uid = p->uid;
s->st_gid = p->gid;
s->st_mode = p->mode | (s->st_mode & ~07777);
return;
}
}
s->st_uid = empty_path_config->uid;
s->st_gid = empty_path_config->gid;
s->st_mode = empty_path_config->mode | (s->st_mode & ~07777);
} else {
// Use the compiled-in fs_config() function.
unsigned st_mode = s->st_mode;
int is_dir = S_ISDIR(s->st_mode) || strcmp(path, TRAILER) == 0;
fs_config(path, is_dir, target_out_path, &s->st_uid, &s->st_gid, &st_mode, &capabilities);
s->st_mode = (typeof(s->st_mode)) st_mode;
}
}
static void _eject(struct stat *s, char *out, int olen, char *data, unsigned datasize)
{
// Nothing is special about this value, just picked something in the
// approximate range that was being used already, and avoiding small
// values which may be special.
static unsigned next_inode = 300000;
while(total_size & 3) {
total_size++;
putchar(0);
}
fix_stat(out, s);
// fprintf(stderr, "_eject %s: mode=0%o\n", out, s->st_mode);
printf("%06x%08x%08x%08x%08x%08x%08x"
"%08x%08x%08x%08x%08x%08x%08x%s%c",
0x070701,
next_inode++, // s.st_ino,
s->st_mode,
0, // s.st_uid,
0, // s.st_gid,
1, // s.st_nlink,
0, // s.st_mtime,
datasize,
0, // volmajor
0, // volminor
0, // devmajor
0, // devminor,
olen + 1,
0,
out,
0
);
total_size += 6 + 8*13 + olen + 1;
if(strlen(out) != (unsigned int)olen) die("ACK!");
while(total_size & 3) {
total_size++;
putchar(0);
}
if(datasize) {
fwrite(data, datasize, 1, stdout);
total_size += datasize;
}
}
static void _eject_trailer()
{
struct stat s;
memset(&s, 0, sizeof(s));
_eject(&s, TRAILER, 10, 0, 0);
while(total_size & 0xff) {
total_size++;
putchar(0);
}
}
static void _archive(char *in, char *out, int ilen, int olen);
static int compare(const void* a, const void* b) {
return strcmp(*(const char**)a, *(const char**)b);
}
static void _archive_dir(char *in, char *out, int ilen, int olen)
{
int i, t;
DIR *d;
struct dirent *de;
if(verbose) {
fprintf(stderr,"_archive_dir('%s','%s',%d,%d)\n",
in, out, ilen, olen);
}
d = opendir(in);
if(d == 0) die("cannot open directory '%s'", in);
int size = 32;
int entries = 0;
char** names = malloc(size * sizeof(char*));
if (names == NULL) {
fprintf(stderr, "failed to allocate dir names array (size %d)\n", size);
exit(1);
}
while((de = readdir(d)) != 0){
/* xxx: feature? maybe some dotfiles are okay */
if(de->d_name[0] == '.') continue;
/* xxx: hack. use a real exclude list */
if(!strcmp(de->d_name, "root")) continue;
if (entries >= size) {
size *= 2;
names = realloc(names, size * sizeof(char*));
if (names == NULL) {
fprintf(stderr, "failed to reallocate dir names array (size %d)\n",
size);
exit(1);
}
}
names[entries] = strdup(de->d_name);
if (names[entries] == NULL) {
fprintf(stderr, "failed to strdup name \"%s\"\n",
de->d_name);
exit(1);
}
++entries;
}
qsort(names, entries, sizeof(char*), compare);
for (i = 0; i < entries; ++i) {
t = strlen(names[i]);
in[ilen] = '/';
memcpy(in + ilen + 1, names[i], t + 1);
if(olen > 0) {
out[olen] = '/';
memcpy(out + olen + 1, names[i], t + 1);
_archive(in, out, ilen + t + 1, olen + t + 1);
} else {
memcpy(out, names[i], t + 1);
_archive(in, out, ilen + t + 1, t);
}
in[ilen] = 0;
out[olen] = 0;
free(names[i]);
}
free(names);
closedir(d);
}
static void _archive(char *in, char *out, int ilen, int olen)
{
struct stat s;
if(verbose) {
fprintf(stderr,"_archive('%s','%s',%d,%d)\n",
in, out, ilen, olen);
}
if(lstat(in, &s)) die("could not stat '%s'\n", in);
if(S_ISREG(s.st_mode)){
char *tmp;
int fd;
fd = open(in, O_RDONLY);
if(fd < 0) die("cannot open '%s' for read", in);
tmp = (char*) malloc(s.st_size);
if(tmp == 0) die("cannot allocate %d bytes", s.st_size);
if(read(fd, tmp, s.st_size) != s.st_size) {
die("cannot read %d bytes", s.st_size);
}
_eject(&s, out, olen, tmp, s.st_size);
free(tmp);
close(fd);
} else if(S_ISDIR(s.st_mode)) {
_eject(&s, out, olen, 0, 0);
_archive_dir(in, out, ilen, olen);
} else if(S_ISLNK(s.st_mode)) {
char buf[1024];
int size;
size = readlink(in, buf, 1024);
if(size < 0) die("cannot read symlink '%s'", in);
_eject(&s, out, olen, buf, size);
} else {
die("Unknown '%s' (mode %d)?\n", in, s.st_mode);
}
}
void archive(const char *start, const char *prefix)
{
char in[8192];
char out[8192];
strcpy(in, start);
strcpy(out, prefix);
_archive_dir(in, out, strlen(in), strlen(out));
}
static void read_canned_config(char* filename)
{
int allocated = 8;
int used = 0;
canned_config =
(struct fs_config_entry*)malloc(allocated * sizeof(struct fs_config_entry));
char line[CANNED_LINE_LENGTH];
FILE* f = fopen(filename, "r");
if (f == NULL) die("failed to open canned file");
while (fgets(line, CANNED_LINE_LENGTH, f) != NULL) {
if (!line[0]) break;
if (used >= allocated) {
allocated *= 2;
canned_config = (struct fs_config_entry*)realloc(
canned_config, allocated * sizeof(struct fs_config_entry));
if (canned_config == NULL) die("failed to reallocate memory");
}
struct fs_config_entry* cc = canned_config + used;
if (isspace(line[0])) {
cc->name = strdup("");
cc->uid = atoi(strtok(line, " \n"));
} else {
cc->name = strdup(strtok(line, " \n"));
cc->uid = atoi(strtok(NULL, " \n"));
}
cc->gid = atoi(strtok(NULL, " \n"));
cc->mode = strtol(strtok(NULL, " \n"), NULL, 8);
++used;
}
if (used >= allocated) {
++allocated;
canned_config = (struct fs_config_entry*)realloc(
canned_config, allocated * sizeof(struct fs_config_entry));
if (canned_config == NULL) die("failed to reallocate memory");
}
canned_config[used].name = NULL;
fclose(f);
}
int main(int argc, char *argv[])
{
argc--;
argv++;
if (argc > 1 && strcmp(argv[0], "-d") == 0) {
target_out_path = argv[1];
argc -= 2;
argv += 2;
}
if (argc > 1 && strcmp(argv[0], "-f") == 0) {
read_canned_config(argv[1]);
argc -= 2;
argv += 2;
}
if(argc == 0) die("no directories to process?!");
while(argc-- > 0){
char *x = strchr(*argv, '=');
if(x != 0) {
*x++ = 0;
} else {
x = "";
}
archive(*argv, x);
argv++;
}
_eject_trailer();
return 0;
}