1 files changed, 697 insertions, 0 deletions

diff --git a/fuse/modules/subdir.c b/fuse/modules/subdir.c
new file mode 100644
index 000000000..05b3379af
--- /dev/null
+++ b/fuse/modules/subdir.c
@@ -0,0 +1,697 @@
+/*
+  fuse subdir module: offset paths with a base directory
+  Copyright (C) 2007  Miklos Szeredi <miklos@szeredi.hu>
+
+  This program can be distributed under the terms of the GNU LGPLv2.
+  See the file COPYING.LIB
+*/
+
+#define FUSE_USE_VERSION 26
+
+#include <fuse.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <string.h>
+#include <errno.h>
+
+struct subdir {
+	char *base;
+	size_t baselen;
+	int rellinks;
+	struct fuse_fs *next;
+};
+
+static struct subdir *subdir_get(void)
+{
+	return fuse_get_context()->private_data;
+}
+
+static int subdir_addpath(struct subdir *d, const char *path, char **newpathp)
+{
+	char *newpath = NULL;
+
+	if (path != NULL) {
+		unsigned newlen = d->baselen + strlen(path);
+
+		newpath = malloc(newlen + 2);
+		if (!newpath)
+			return -ENOMEM;
+
+		if (path[0] == '/')
+			path++;
+		strcpy(newpath, d->base);
+		strcpy(newpath + d->baselen, path);
+		if (!newpath[0])
+			strcpy(newpath, ".");
+	}
+	*newpathp = newpath;
+
+	return 0;
+}
+
+static int subdir_getattr(const char *path, struct stat *stbuf)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_getattr(d->next, newpath, stbuf);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_fgetattr(const char *path, struct stat *stbuf,
+			   struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_fgetattr(d->next, newpath, stbuf, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_access(const char *path, int mask)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_access(d->next, newpath, mask);
+		free(newpath);
+	}
+	return err;
+}
+
+
+static int count_components(const char *p)
+{
+	int ctr;
+
+	for (; *p == '/'; p++);
+	for (ctr = 0; *p; ctr++) {
+		for (; *p && *p != '/'; p++);
+		for (; *p == '/'; p++);
+	}
+	return ctr;
+}
+
+static void strip_common(const char **sp, const char **tp)
+{
+	const char *s = *sp;
+	const char *t = *tp;
+	do {
+		for (; *s == '/'; s++);
+		for (; *t == '/'; t++);
+		*tp = t;
+		*sp = s;
+		for (; *s == *t && *s && *s != '/'; s++, t++);
+	} while ((*s == *t && *s) || (!*s && *t == '/') || (*s == '/' && !*t));
+}
+
+static void transform_symlink(struct subdir *d, const char *path,
+			      char *buf, size_t size)
+{
+	const char *l = buf;
+	size_t llen;
+	char *s;
+	int dotdots;
+	int i;
+
+	if (l[0] != '/' || d->base[0] != '/')
+		return;
+
+	strip_common(&l, &path);
+	if (l - buf < (long) d->baselen)
+		return;
+
+	dotdots = count_components(path);
+	if (!dotdots)
+		return;
+	dotdots--;
+
+	llen = strlen(l);
+	if (dotdots * 3 + llen + 2 > size)
+		return;
+
+	s = buf + dotdots * 3;
+	if (llen)
+		memmove(s, l, llen + 1);
+	else if (!dotdots)
+		strcpy(s, ".");
+	else
+		*s = '\0';
+
+	for (s = buf, i = 0; i < dotdots; i++, s += 3)
+		memcpy(s, "../", 3);
+}
+
+
+static int subdir_readlink(const char *path, char *buf, size_t size)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_readlink(d->next, newpath, buf, size);
+		if (!err && d->rellinks)
+			transform_symlink(d, newpath, buf, size);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_opendir(const char *path, struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_opendir(d->next, newpath, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_readdir(const char *path, void *buf,
+			  fuse_fill_dir_t filler, loff_t offset,
+			  struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_readdir(d->next, newpath, buf, filler, offset,
+				      fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_releasedir(const char *path, struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_releasedir(d->next, newpath, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_mknod(const char *path, mode_t mode, dev_t rdev)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_mknod(d->next, newpath, mode, rdev);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_mkdir(const char *path, mode_t mode)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_mkdir(d->next, newpath, mode);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_unlink(const char *path)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_unlink(d->next, newpath);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_rmdir(const char *path)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_rmdir(d->next, newpath);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_symlink(const char *from, const char *path)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_symlink(d->next, from, newpath);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_rename(const char *from, const char *to)
+{
+	struct subdir *d = subdir_get();
+	char *newfrom;
+	char *newto;
+	int err = subdir_addpath(d, from, &newfrom);
+	if (!err) {
+		err = subdir_addpath(d, to, &newto);
+		if (!err) {
+			err = fuse_fs_rename(d->next, newfrom, newto);
+			free(newto);
+		}
+		free(newfrom);
+	}
+	return err;
+}
+
+static int subdir_link(const char *from, const char *to)
+{
+	struct subdir *d = subdir_get();
+	char *newfrom;
+	char *newto;
+	int err = subdir_addpath(d, from, &newfrom);
+	if (!err) {
+		err = subdir_addpath(d, to, &newto);
+		if (!err) {
+			err = fuse_fs_link(d->next, newfrom, newto);
+			free(newto);
+		}
+		free(newfrom);
+	}
+	return err;
+}
+
+static int subdir_chmod(const char *path, mode_t mode)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_chmod(d->next, newpath, mode);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_chown(const char *path, uid_t uid, gid_t gid)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_chown(d->next, newpath, uid, gid);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_truncate(const char *path, loff_t size)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_truncate(d->next, newpath, size);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_ftruncate(const char *path, loff_t size,
+			    struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_ftruncate(d->next, newpath, size, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_utimens(const char *path, const struct timespec ts[2])
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_utimens(d->next, newpath, ts);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_create(const char *path, mode_t mode,
+			 struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_create(d->next, newpath, mode, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_open(const char *path, struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_open(d->next, newpath, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_read_buf(const char *path, struct fuse_bufvec **bufp,
+			   size_t size, loff_t offset, struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_read_buf(d->next, newpath, bufp, size, offset, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_write_buf(const char *path, struct fuse_bufvec *buf,
+			loff_t offset, struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_write_buf(d->next, newpath, buf, offset, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_statfs(const char *path, struct statvfs *stbuf)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_statfs(d->next, newpath, stbuf);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_flush(const char *path, struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_flush(d->next, newpath, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_release(const char *path, struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_release(d->next, newpath, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_fsync(const char *path, int isdatasync,
+			struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_fsync(d->next, newpath, isdatasync, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_fsyncdir(const char *path, int isdatasync,
+			   struct fuse_file_info *fi)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_fsyncdir(d->next, newpath, isdatasync, fi);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_setxattr(const char *path, const char *name,
+			   const char *value, size_t size, int flags)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_setxattr(d->next, newpath, name, value, size,
+				       flags);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_getxattr(const char *path, const char *name, char *value,
+			   size_t size)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_getxattr(d->next, newpath, name, value, size);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_listxattr(const char *path, char *list, size_t size)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_listxattr(d->next, newpath, list, size);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_removexattr(const char *path, const char *name)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_removexattr(d->next, newpath, name);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_lock(const char *path, struct fuse_file_info *fi, int cmd,
+		       struct flock *lock)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_lock(d->next, newpath, fi, cmd, lock);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_flock(const char *path, struct fuse_file_info *fi, int op)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_flock(d->next, newpath, fi, op);
+		free(newpath);
+	}
+	return err;
+}
+
+static int subdir_bmap(const char *path, size_t blocksize, uint64_t *idx)
+{
+	struct subdir *d = subdir_get();
+	char *newpath;
+	int err = subdir_addpath(d, path, &newpath);
+	if (!err) {
+		err = fuse_fs_bmap(d->next, newpath, blocksize, idx);
+		free(newpath);
+	}
+	return err;
+}
+
+static void *subdir_init(struct fuse_conn_info *conn)
+{
+	struct subdir *d = subdir_get();
+	fuse_fs_init(d->next, conn);
+	return d;
+}
+
+static void subdir_destroy(void *data)
+{
+	struct subdir *d = data;
+	fuse_fs_destroy(d->next);
+	free(d->base);
+	free(d);
+}
+
+static const struct fuse_operations subdir_oper = {
+	.destroy	= subdir_destroy,
+	.init		= subdir_init,
+	.getattr	= subdir_getattr,
+	.fgetattr	= subdir_fgetattr,
+	.access		= subdir_access,
+	.readlink	= subdir_readlink,
+	.opendir	= subdir_opendir,
+	.readdir	= subdir_readdir,
+	.releasedir	= subdir_releasedir,
+	.mknod		= subdir_mknod,
+	.mkdir		= subdir_mkdir,
+	.symlink	= subdir_symlink,
+	.unlink		= subdir_unlink,
+	.rmdir		= subdir_rmdir,
+	.rename		= subdir_rename,
+	.link		= subdir_link,
+	.chmod		= subdir_chmod,
+	.chown		= subdir_chown,
+	.truncate	= subdir_truncate,
+	.ftruncate	= subdir_ftruncate,
+	.utimens	= subdir_utimens,
+	.create		= subdir_create,
+	.open		= subdir_open,
+	.read_buf	= subdir_read_buf,
+	.write_buf	= subdir_write_buf,
+	.statfs		= subdir_statfs,
+	.flush		= subdir_flush,
+	.release	= subdir_release,
+	.fsync		= subdir_fsync,
+	.fsyncdir	= subdir_fsyncdir,
+	.setxattr	= subdir_setxattr,
+	.getxattr	= subdir_getxattr,
+	.listxattr	= subdir_listxattr,
+	.removexattr	= subdir_removexattr,
+	.lock		= subdir_lock,
+	.flock		= subdir_flock,
+	.bmap		= subdir_bmap,
+
+	.flag_nullpath_ok = 1,
+	.flag_nopath = 1,
+};
+
+static const struct fuse_opt subdir_opts[] = {
+	FUSE_OPT_KEY("-h", 0),
+	FUSE_OPT_KEY("--help", 0),
+	{ "subdir=%s", offsetof(struct subdir, base), 0 },
+	{ "rellinks", offsetof(struct subdir, rellinks), 1 },
+	{ "norellinks", offsetof(struct subdir, rellinks), 0 },
+	FUSE_OPT_END
+};
+
+static void subdir_help(void)
+{
+	fprintf(stderr,
+"    -o subdir=DIR	    prepend this directory to all paths (mandatory)\n"
+"    -o [no]rellinks	    transform absolute symlinks to relative\n");
+}
+
+static int subdir_opt_proc(void *data, const char *arg, int key,
+			   struct fuse_args *outargs)
+{
+	(void) data; (void) arg; (void) outargs;
+
+	if (!key) {
+		subdir_help();
+		return -1;
+	}
+
+	return 1;
+}
+
+static struct fuse_fs *subdir_new(struct fuse_args *args,
+				  struct fuse_fs *next[])
+{
+	struct fuse_fs *fs;
+	struct subdir *d;
+
+	d = calloc(1, sizeof(struct subdir));
+	if (d == NULL) {
+		fprintf(stderr, "fuse-subdir: memory allocation failed\n");
+		return NULL;
+	}
+
+	if (fuse_opt_parse(args, d, subdir_opts, subdir_opt_proc) == -1)
+		goto out_free;
+
+	if (!next[0] || next[1]) {
+		fprintf(stderr, "fuse-subdir: exactly one next filesystem required\n");
+		goto out_free;
+	}
+
+	if (!d->base) {
+		fprintf(stderr, "fuse-subdir: missing 'subdir' option\n");
+		goto out_free;
+	}
+
+	if (d->base[0] && d->base[strlen(d->base)-1] != '/') {
+		char *tmp = realloc(d->base, strlen(d->base) + 2);
+		if (!tmp) {
+			fprintf(stderr, "fuse-subdir: memory allocation failed\n");
+			goto out_free;
+		}
+		d->base = tmp;
+		strcat(d->base, "/");
+	}
+	d->baselen = strlen(d->base);
+	d->next = next[0];
+	fs = fuse_fs_new(&subdir_oper, sizeof(subdir_oper), d);
+	if (!fs)
+		goto out_free;
+	return fs;
+
+out_free:
+	free(d->base);
+	free(d);
+	return NULL;
+}
+
+FUSE_REGISTER_MODULE(subdir, subdir_new);