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-rw-r--r--fuse/modules/subdir.c697
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);
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-18 01:06:22 +0200