Initial Contribution
diff --git a/toolbox/mount.c b/toolbox/mount.c
new file mode 100644
index 0000000..ef13e1f
--- /dev/null
+++ b/toolbox/mount.c
@@ -0,0 +1,273 @@
+/*
+ * mount.c, by rmk
+ */
+
+#include <sys/mount.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <linux/loop.h>
+
+#define ARRAY_SIZE(x) (sizeof(x) / sizeof(x[0]))
+
+// FIXME - only one loop mount is supported at a time
+#define LOOP_DEVICE "/dev/block/loop0"
+
+struct mount_opts {
+ const char str[8];
+ unsigned long rwmask;
+ unsigned long rwset;
+ unsigned long rwnoset;
+};
+
+struct extra_opts {
+ char *str;
+ char *end;
+ int used_size;
+ int alloc_size;
+};
+
+/*
+ * These options define the function of "mount(2)".
+ */
+#define MS_TYPE (MS_REMOUNT|MS_BIND|MS_MOVE)
+
+
+static const struct mount_opts options[] = {
+ /* name mask set noset */
+ { "async", MS_SYNCHRONOUS, 0, MS_SYNCHRONOUS },
+ { "atime", MS_NOATIME, 0, MS_NOATIME },
+ { "bind", MS_TYPE, MS_BIND, 0, },
+ { "dev", MS_NODEV, 0, MS_NODEV },
+ { "diratime", MS_NODIRATIME, 0, MS_NODIRATIME },
+ { "dirsync", MS_DIRSYNC, MS_DIRSYNC, 0 },
+ { "exec", MS_NOEXEC, 0, MS_NOEXEC },
+ { "move", MS_TYPE, MS_MOVE, 0 },
+ { "recurse", MS_REC, MS_REC, 0 },
+ { "remount", MS_TYPE, MS_REMOUNT, 0 },
+ { "ro", MS_RDONLY, MS_RDONLY, 0 },
+ { "rw", MS_RDONLY, 0, MS_RDONLY },
+ { "suid", MS_NOSUID, 0, MS_NOSUID },
+ { "sync", MS_SYNCHRONOUS, MS_SYNCHRONOUS, 0 },
+ { "verbose", MS_VERBOSE, MS_VERBOSE, 0 },
+};
+
+static void add_extra_option(struct extra_opts *extra, char *s)
+{
+ int len = strlen(s);
+ int newlen = extra->used_size + len;
+
+ if (extra->str)
+ len++; /* +1 for ',' */
+
+ if (newlen >= extra->alloc_size) {
+ char *new;
+
+ new = realloc(extra->str, newlen + 1); /* +1 for NUL */
+ if (!new)
+ return;
+
+ extra->str = new;
+ extra->end = extra->str + extra->used_size;
+ extra->alloc_size = newlen;
+ }
+
+ if (extra->used_size) {
+ *extra->end = ',';
+ extra->end++;
+ }
+ strcpy(extra->end, s);
+ extra->used_size += len;
+
+}
+
+static unsigned long
+parse_mount_options(char *arg, unsigned long rwflag, struct extra_opts *extra, int* loop)
+{
+ char *s;
+
+ *loop = 0;
+ while ((s = strsep(&arg, ",")) != NULL) {
+ char *opt = s;
+ unsigned int i;
+ int res, no = s[0] == 'n' && s[1] == 'o';
+
+ if (no)
+ s += 2;
+
+ if (strcmp(s, "loop") == 0) {
+ *loop = 1;
+ continue;
+ }
+ for (i = 0, res = 1; i < ARRAY_SIZE(options); i++) {
+ res = strcmp(s, options[i].str);
+
+ if (res == 0) {
+ rwflag &= ~options[i].rwmask;
+ if (no)
+ rwflag |= options[i].rwnoset;
+ else
+ rwflag |= options[i].rwset;
+ }
+ if (res <= 0)
+ break;
+ }
+
+ if (res != 0 && s[0])
+ add_extra_option(extra, opt);
+ }
+
+ return rwflag;
+}
+
+static char *progname;
+
+static struct extra_opts extra;
+static unsigned long rwflag;
+
+static int
+do_mount(char *dev, char *dir, char *type, unsigned long rwflag, void *data, int loop)
+{
+ char *s;
+ int error = 0;
+
+ if (loop) {
+ int file_fd, device_fd;
+
+ // FIXME - only one loop mount supported at a time
+ file_fd = open(dev, O_RDWR);
+ if (file_fd < -1) {
+ perror("open backing file failed");
+ return 1;
+ }
+ device_fd = open(LOOP_DEVICE, O_RDWR);
+ if (device_fd < -1) {
+ perror("open loop device failed");
+ close(file_fd);
+ return 1;
+ }
+ if (ioctl(device_fd, LOOP_SET_FD, file_fd) < 0) {
+ perror("ioctl LOOP_SET_FD failed");
+ close(file_fd);
+ close(device_fd);
+ return 1;
+ }
+
+ close(file_fd);
+ close(device_fd);
+ dev = LOOP_DEVICE;
+ }
+
+ while ((s = strsep(&type, ",")) != NULL) {
+retry:
+ if (mount(dev, dir, s, rwflag, data) == -1) {
+ error = errno;
+ /*
+ * If the filesystem is not found, or the
+ * superblock is invalid, try the next.
+ */
+ if (error == ENODEV || error == EINVAL)
+ continue;
+
+ /*
+ * If we get EACCESS, and we're trying to
+ * mount readwrite and this isn't a remount,
+ * try read only.
+ */
+ if (error == EACCES &&
+ (rwflag & (MS_REMOUNT|MS_RDONLY)) == 0) {
+ rwflag |= MS_RDONLY;
+ goto retry;
+ }
+ break;
+ }
+ }
+
+ if (error) {
+ errno = error;
+ perror("mount");
+ return 255;
+ }
+
+ return 0;
+}
+
+static int print_mounts()
+{
+ FILE* f;
+ int length;
+ char buffer[100];
+
+ f = fopen("/proc/mounts", "r");
+ if (!f) {
+ fprintf(stdout, "could not open /proc/mounts\n");
+ return -1;
+ }
+
+ do {
+ length = fread(buffer, 1, 100, f);
+ if (length > 0)
+ fwrite(buffer, 1, length, stdout);
+ } while (length > 0);
+
+ fclose(f);
+ return 0;
+}
+
+int mount_main(int argc, char *argv[])
+{
+ char *type = NULL;
+ int c;
+ int loop;
+
+ progname = argv[0];
+ rwflag = MS_VERBOSE;
+
+ // mount with no arguments is equivalent to "cat /proc/mounts"
+ if (argc == 1) return print_mounts();
+
+ do {
+ c = getopt(argc, argv, "o:rt:w");
+ if (c == EOF)
+ break;
+ switch (c) {
+ case 'o':
+ rwflag = parse_mount_options(optarg, rwflag, &extra, &loop);
+ break;
+ case 'r':
+ rwflag |= MS_RDONLY;
+ break;
+ case 't':
+ type = optarg;
+ break;
+ case 'w':
+ rwflag &= ~MS_RDONLY;
+ break;
+ case '?':
+ fprintf(stderr, "%s: invalid option -%c\n",
+ progname, optopt);
+ exit(1);
+ }
+ } while (1);
+
+ /*
+ * If remount, bind or move was specified, then we don't
+ * have a "type" as such. Use the dummy "none" type.
+ */
+ if (rwflag & MS_TYPE)
+ type = "none";
+
+ if (optind + 2 != argc || type == NULL) {
+ fprintf(stderr, "Usage: %s [-r] [-w] [-o options] [-t type] "
+ "device directory\n", progname);
+ exit(1);
+ }
+
+ return do_mount(argv[optind], argv[optind + 1], type, rwflag,
+ extra.str, loop);
+}