Merge "Switch to toybox mount(1)."

    log \

    ls \

    lsof \

    mount \

    nandread \

    newfs_msdos \

    ps \

/*

 * 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]))

#define DEFAULT_LOOP_DEVICE "/dev/block/loop0"

#define LOOPDEV_MAXLEN 64

struct mount_opts {

	const char str[16];

	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		},

	{ "rec",	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		},

	{ "unbindable",	MS_UNBINDABLE,	MS_UNBINDABLE,	0		},

	{ "private",	MS_PRIVATE,	MS_PRIVATE,	0		},

	{ "slave",	MS_SLAVE,	MS_SLAVE,	0		},

	{ "shared",	MS_SHARED,	MS_SHARED,	0		},

};

static void add_extra_option(struct extra_opts *extra, char *s)

{

	int len = strlen(s);

	int newlen;

	if (extra->str)

	       len++;			/* +1 for ',' */

	newlen = extra->used_size + len;

	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 + 1;

	}

	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 *loopdev)

{

	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 (strncmp(s, "loop=", 5) == 0) {

            *loop = 1;

            strlcpy(loopdev, s + 5, LOOPDEV_MAXLEN);

            continue;

        }

        if (strcmp(s, "loop") == 0) {

            *loop = 1;

            strlcpy(loopdev, DEFAULT_LOOP_DEVICE, LOOPDEV_MAXLEN);

            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;

}

/*

 * Mark the given block device as read-write, using the BLKROSET ioctl.

 */

static void fs_set_blk_rw(const char *blockdev)

{

    int fd;

    int OFF = 0;

    fd = open(blockdev, O_RDONLY);

    if (fd < 0) {

        // should never happen

        return;

    }

    ioctl(fd, BLKROSET, &OFF);

    close(fd);

}

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 *loopdev)

{

	char *s;

	int error = 0;

    if (loop) {

        int file_fd, device_fd;

        int flags;

        flags = (rwflag & MS_RDONLY) ? O_RDONLY : O_RDWR;

        file_fd = open(dev, flags);

        if (file_fd < 0) {

            perror("open backing file failed");

            return 1;

        }

        device_fd = open(loopdev, flags);

        if (device_fd < 0) {

            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 = loopdev;

    }

    if ((rwflag & MS_RDONLY) == 0) {

        fs_set_blk_rw(dev);

    }

	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;

}

static int get_mounts_dev_dir(const char *arg, char **dev, char **dir)

{

	FILE *f;

	char mount_dev[256];

	char mount_dir[256];

	char mount_type[256];

	char mount_opts[256];

	int mount_freq;

	int mount_passno;

	int match;

	f = fopen("/proc/mounts", "r");

	if (!f) {

		fprintf(stdout, "could not open /proc/mounts\n");

		return -1;

	}

	do {

		match = fscanf(f, "%255s %255s %255s %255s %d %d\n",

					   mount_dev, mount_dir, mount_type,

					   mount_opts, &mount_freq, &mount_passno);

		mount_dev[255] = 0;

		mount_dir[255] = 0;

		mount_type[255] = 0;

		mount_opts[255] = 0;

		if (match == 6 &&

			(strcmp(arg, mount_dev) == 0 ||

			 strcmp(arg, mount_dir) == 0)) {

			*dev = strdup(mount_dev);

			*dir = strdup(mount_dir);

			fclose(f);

			return 0;

		}

	} while (match != EOF);

	fclose(f);

	return -1;

}

int mount_main(int argc, char *argv[])

{

	char *type = NULL;

	char *dev = NULL;

	char *dir = NULL;

	int c;

	int loop = 0;

	char loopdev[LOOPDEV_MAXLEN];

	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, loopdev);

			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) {

		dev = argv[optind];

		dir = argv[optind + 1];

	} else if (optind + 1 == argc && rwflag & MS_REMOUNT) {

		get_mounts_dev_dir(argv[optind], &dev, &dir);

	}

	if (dev == NULL || dir == NULL || type == NULL) {

		fprintf(stderr, "Usage: %s [-r] [-w] [-o options] [-t type] "

			"device directory\n", progname);

		exit(1);

	}

	return do_mount(dev, dir, type, rwflag, extra.str, loop, loopdev);

	/* We leak dev and dir in some cases, but we're about to exit */

}