/* * mount.c * * This file implements mounting of WIM files using FUSE, which stands for * Filesystem in Userspace. FUSE allows a filesystem to be implemented in a * userspace process by implementing the filesystem primitives--- read(), * write(), readdir(), etc. */ /* * Copyright (C) 2012 Eric Biggers * * This file is part of wimlib, a library for working with WIM files. * * wimlib is free software; you can redistribute it and/or modify it under the * terms of the GNU General Public License as published by the Free * Software Foundation; either version 3 of the License, or (at your option) * any later version. * * wimlib is distributed in the hope that it will be useful, but WITHOUT ANY * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR * A PARTICULAR PURPOSE. See the GNU General Public License for more * details. * * You should have received a copy of the GNU General Public License * along with wimlib; if not, see http://www.gnu.org/licenses/. */ #include "wimlib_internal.h" #ifdef WITH_FUSE #include "sha1.h" #include "lookup_table.h" #include "xml.h" #include "io.h" #include "timestamp.h" #include #include #include #define FUSE_USE_VERSION 26 #include #include #include #include #include #include #include #ifdef ENABLE_XATTR #include #endif /* File descriptor to a file open on the WIM filesystem. */ struct wimlib_fd { struct inode *f_inode; struct lookup_table_entry *lte; int staging_fd; u16 idx; u32 stream_id; }; /* The WIMStruct for the mounted WIM. */ static WIMStruct *w; /* Working directory when `imagex mount' is run. */ static const char *working_directory; /* Name of the staging directory for a read-write mount. Whenever a new file is * created, it is done so in the staging directory. Furthermore, whenever a * file in the WIM is modified, it is extracted to the staging directory. If * changes are commited when the WIM is unmounted, the file resources are merged * in from the staging directory when writing the new WIM. */ static char *staging_dir_name; static size_t staging_dir_name_len; /* Flags passed to wimlib_mount(). */ static int mount_flags; /* Name of the directory on which the WIM file is mounted. */ static const char *mount_dir; /* Next inode number to be assigned. */ static u64 next_ino; /* List of lookup table entries in the staging directory */ static LIST_HEAD(staging_list); static inline int get_lookup_flags() { if (mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS) return LOOKUP_FLAG_ADS_OK; else return 0; } /* Returns nonzero if write permission is requested on the file open flags */ static inline int flags_writable(int open_flags) { return open_flags & (O_RDWR | O_WRONLY); } /* * Allocate a file descriptor for a stream. * * @inode: inode containing the stream we're opening * @stream_id: ID of the stream we're opening * @lte: Lookup table entry for the stream (may be NULL) * @fd_ret: Return the allocated file descriptor if successful. * * Return 0 iff successful or error code if unsuccessful. */ static int alloc_wimlib_fd(struct inode *inode, u32 stream_id, struct lookup_table_entry *lte, struct wimlib_fd **fd_ret) { static const u16 fds_per_alloc = 8; static const u16 max_fds = 0xffff; DEBUG("Allocating fd for stream ID %u from inode %lx (open = %u, allocated = %u)", stream_id, inode->ino, inode->num_opened_fds, inode->num_allocated_fds); if (inode->num_opened_fds == inode->num_allocated_fds) { struct wimlib_fd **fds; u16 num_new_fds; if (inode->num_allocated_fds == max_fds) return -EMFILE; num_new_fds = min(fds_per_alloc, max_fds - inode->num_allocated_fds); fds = REALLOC(inode->fds, (inode->num_allocated_fds + num_new_fds) * sizeof(inode->fds[0])); if (!fds) return -ENOMEM; memset(&fds[inode->num_allocated_fds], 0, num_new_fds * sizeof(fds[0])); inode->fds = fds; inode->num_allocated_fds += num_new_fds; } for (u16 i = 0; ; i++) { if (!inode->fds[i]) { struct wimlib_fd *fd = CALLOC(1, sizeof(*fd)); if (!fd) return -ENOMEM; fd->f_inode = inode; fd->lte = lte; fd->staging_fd = -1; fd->idx = i; fd->stream_id = stream_id; *fd_ret = fd; inode->fds[i] = fd; inode->num_opened_fds++; if (lte) lte->num_opened_fds++; DEBUG("Allocated fd"); return 0; } } } static void inode_put_fd(struct inode *inode, struct wimlib_fd *fd) { wimlib_assert(fd); wimlib_assert(inode); wimlib_assert(fd->f_inode == inode); wimlib_assert(inode->num_opened_fds); wimlib_assert(fd->idx < inode->num_opened_fds); wimlib_assert(inode->fds[fd->idx] == fd); inode->fds[fd->idx] = NULL; FREE(fd); if (--inode->num_opened_fds == 0 && inode->link_count == 0) free_inode(inode); } static int lte_put_fd(struct lookup_table_entry *lte, struct wimlib_fd *fd) { wimlib_assert(fd); wimlib_assert(fd->lte == lte); if (!lte) /* Empty stream with no lookup table entry */ return 0; /* Close staging file descriptor if needed. */ wimlib_assert(lte->num_opened_fds); if (lte->resource_location == RESOURCE_IN_STAGING_FILE) { wimlib_assert(lte->staging_file_name); wimlib_assert(fd->staging_fd != -1); if (close(fd->staging_fd) != 0) { ERROR_WITH_ERRNO("Failed to close staging file"); return -errno; } } lte_decrement_num_opened_fds(lte, w->lookup_table); return 0; } /* Close a file descriptor. */ static int close_wimlib_fd(struct wimlib_fd *fd) { int ret; wimlib_assert(fd); DEBUG("Closing fd (inode = %lu, opened = %u, allocated = %u)", fd->f_inode->ino, fd->f_inode->num_opened_fds, fd->f_inode->num_allocated_fds); ret = lte_put_fd(fd->lte, fd); if (ret != 0) return ret; inode_put_fd(fd->f_inode, fd); return 0; } /* Remove a dentry; i.e. remove a reference to the corresponding inode. * * If there are no remaining references to the inode either through dentries or * open file descriptors, the inode is freed. Otherwise, the inode is not * removed, but the dentry is unlinked and freed. * * Either way, all lookup table entries referenced by the inode have their * reference count decremented. If a lookup table entry has no open file * descriptors and no references remaining, it is freed, and the staging file is * unlinked. */ static void remove_dentry(struct dentry *dentry, struct lookup_table *lookup_table) { struct inode *inode = dentry->d_inode; struct lookup_table_entry *lte; unsigned i; for (i = 0; i <= inode->num_ads; i++) { lte = inode_stream_lte_resolved(inode, i); if (lte) lte_decrement_refcnt(lte, lookup_table); } unlink_dentry(dentry); put_dentry(dentry); } /* Creates a new staging file and returns its file descriptor opened for * writing. * * @name_ret: A location into which the a pointer to the newly allocated name of * the staging file is stored. * @return: The file descriptor for the new file. Returns -1 and sets errno on * error, for any reason possible from the creat() function. */ static int create_staging_file(char **name_ret, int open_flags) { size_t name_len; char *name; struct stat stbuf; int fd; int errno_save; name_len = staging_dir_name_len + 1 + SHA1_HASH_SIZE; name = MALLOC(name_len + 1); if (!name) { errno = ENOMEM; return -1; } do { memcpy(name, staging_dir_name, staging_dir_name_len); name[staging_dir_name_len] = '/'; randomize_char_array_with_alnum(name + staging_dir_name_len + 1, SHA1_HASH_SIZE); name[name_len] = '\0'; /* Just in case, verify that the randomly generated name doesn't name an * existing file, and try again if so */ } while (stat(name, &stbuf) == 0); if (errno != ENOENT) /* other error! */ return -1; /* doesn't exist--- ok */ DEBUG("Creating staging file `%s'", name); fd = open(name, open_flags | O_CREAT | O_TRUNC, 0600); if (fd == -1) { errno_save = errno; FREE(name); errno = errno_save; } else { *name_ret = name; } return fd; } /* * Extract a WIM resource to the staging directory. * * @inode: Inode that contains the stream we are extracting * * @stream_id: Identifier for the stream (it stays constant even if the indices * of the stream entries are changed) * * @lte: Pointer to pointer to the lookup table entry for the stream we need to * extract, or NULL if there was no lookup table entry present for the stream * * @size: Number of bytes of the stream we want to extract (this supports the * wimfs_truncate() function). */ static int extract_resource_to_staging_dir(struct inode *inode, u32 stream_id, struct lookup_table_entry **lte, off_t size) { char *staging_file_name; int ret; int fd; struct lookup_table_entry *old_lte, *new_lte; old_lte = *lte; fd = create_staging_file(&staging_file_name, O_WRONLY); if (fd == -1) return -errno; if (old_lte) ret = extract_wim_resource_to_fd(old_lte, fd, size); else ret = 0; if (ret != 0 || close(fd) != 0) { if (errno != 0) ret = -errno; else ret = -EIO; close(fd); goto out_delete_staging_file; } if (old_lte && inode->link_count == old_lte->refcnt) { /* The reference count of the existing lookup table * entry is the same as the link count of the inode that * contains the stream we're opening. Therefore, ALL * the references to the lookup table entry correspond * to the stream we're trying to extract, so the lookup * table entry can be re-used. */ DEBUG("Re-using lookup table entry"); lookup_table_unlink(w->lookup_table, old_lte); new_lte = old_lte; } else { if (old_lte) { /* There's an existing lookup table entry, but its * reference count is creater than the link count for * the inode containing a stream we're opening. * Therefore, we need to split the lookup table entry. * */ wimlib_assert(old_lte->refcnt > inode->link_count); DEBUG("Splitting lookup table entry " "(inode->link_count = %zu, old_lte->refcnt = %u)", inode->link_count, old_lte->refcnt); } new_lte = new_lookup_table_entry(); if (!new_lte) { ret = -ENOMEM; goto out_delete_staging_file; } /* There may already be open file descriptors to this stream if * it's previously been opened read-only, but just now we're * opening it read-write. Identify those file descriptors and * change their lookup table entry pointers to point to the new * lookup table entry, and open staging file descriptors for * them. * * At the same time, we need to count the number of these opened * file descriptors to the new lookup table entry. If there's * an old lookup table entry, this number needs to be subtracted * from the fd's opened to the old entry. */ for (u16 i = 0, j = 0; j < inode->num_opened_fds; i++) { struct wimlib_fd *fd = inode->fds[i]; if (fd) { if (fd->stream_id == stream_id) { wimlib_assert(fd->lte == old_lte); fd->lte = new_lte; new_lte->num_opened_fds++; fd->staging_fd = open(staging_file_name, O_RDONLY); if (fd->staging_fd == -1) { ret = -errno; goto out_revert_fd_changes; } } j++; } } DEBUG("%zu fd's were already opened to the file we extracted", new_lte->num_opened_fds); if (old_lte) { old_lte->num_opened_fds -= new_lte->num_opened_fds; old_lte->refcnt -= inode->link_count; } } new_lte->resource_entry.original_size = size; new_lte->refcnt = inode->link_count; new_lte->staging_file_name = staging_file_name; new_lte->resource_location = RESOURCE_IN_STAGING_FILE; new_lte->lte_inode = inode; random_hash(new_lte->hash); if (stream_id == 0) inode->lte = new_lte; else for (u16 i = 0; i < inode->num_ads; i++) if (inode->ads_entries[i].stream_id == stream_id) inode->ads_entries[i].lte = new_lte; lookup_table_insert(w->lookup_table, new_lte); list_add(&new_lte->staging_list, &staging_list); *lte = new_lte; return 0; out_revert_fd_changes: for (u16 i = 0, j = 0; j < new_lte->num_opened_fds; i++) { struct wimlib_fd *fd = inode->fds[i]; if (fd && fd->stream_id == stream_id && fd->lte == new_lte) { fd->lte = old_lte; if (fd->staging_fd != -1) { close(fd->staging_fd); fd->staging_fd = -1; } j++; } } out_free_new_lte: free_lookup_table_entry(new_lte); out_delete_staging_file: unlink(staging_file_name); FREE(staging_file_name); return ret; } /* * Creates a randomly named staging directory and returns its name into the * static variable staging_dir_name. * * If the staging directory cannot be created, staging_dir_name is set to NULL. * */ static void make_staging_dir() { /* XXX Give the user an option of where to stage files */ static char prefix[] = "wimlib-staging-"; static const size_t prefix_len = 15; static const size_t suffix_len = 10; size_t pwd_len = strlen(working_directory); staging_dir_name_len = pwd_len + 1 + prefix_len + suffix_len; staging_dir_name = MALLOC(staging_dir_name_len + 1); if (!staging_dir_name) { ERROR("Out of memory"); return; } memcpy(staging_dir_name, working_directory, pwd_len); staging_dir_name[pwd_len] = '/'; memcpy(staging_dir_name + pwd_len + 1, prefix, prefix_len); randomize_char_array_with_alnum(staging_dir_name + pwd_len + 1 + prefix_len, suffix_len); staging_dir_name[staging_dir_name_len] = '\0'; if (mkdir(staging_dir_name, 0700) != 0) { ERROR_WITH_ERRNO("Failed to create temporary directory `%s'", staging_dir_name); FREE(staging_dir_name); staging_dir_name = NULL; } } static int remove_file_or_directory(const char *fpath, const struct stat *sb, int typeflag, struct FTW *ftwbuf) { if (remove(fpath) == 0) return 0; else return WIMLIB_ERR_DELETE_STAGING_DIR; } /* * Deletes the staging directory and all the files contained in it. */ static int delete_staging_dir() { int ret; ret = nftw(staging_dir_name, remove_file_or_directory,10, FTW_DEPTH); staging_dir_name = NULL; return ret; } /* Name and message queue descriptors for message queues between the filesystem * daemon process and the unmount process. These are used when the filesystem * is unmounted and the process running wimlib_mount() (i.e. the `imagex * unmount' command) needs to communicate with the filesystem daemon running * fuse_main() (i.e. that spawned by the `imagex mount' or `imagex mountrw' * commands */ static char *unmount_to_daemon_mq_name; static char *daemon_to_unmount_mq_name; static mqd_t unmount_to_daemon_mq; static mqd_t daemon_to_unmount_mq; /* Simple function that returns the concatenation of 4 strings. */ static char *strcat_dup(const char *s1, const char *s2, const char *s3, const char *s4) { size_t len = strlen(s1) + strlen(s2) + strlen(s3) + strlen(s4) + 1; char *p = MALLOC(len); if (!p) return NULL; p = strcpy(p, s1); p = strcat(p, s2); p = strcat(p, s3); return strcat(p, s4); } /* Removes trailing forward slashes in a string. */ static void remove_trailing_slashes(char *s) { long len = strlen(s); for (long i = len - 1; i >= 1; i--) { if (s[i] == '/') s[i] = '\0'; else break; } } /* Changes forward slashes to underscores in a string. */ static void s_slashes_underscores_g(char *s) { while (*s) { if (*s == '/') *s = '_'; s++; } } /* * Opens two POSIX message queue: one for sending messages from the unmount * process to the daemon process, and one to go the other way. The names of the * message queues, which must be system-wide unique, are be based on the mount * point. (There of course is still a possibility of a collision if one were to * unmount two identically named directories simultaneously...) * * @daemon specifies whether the calling process is the filesystem daemon or the * unmount process. */ static int open_message_queues(bool daemon) { static const char *slash = "/"; static const char *prefix = "wimlib-"; static const char *u2d_suffix = "unmount-to-daemon-mq"; static const char *d2u_suffix = "daemon-to-unmount-mq"; const char *mount_dir_basename = path_basename(mount_dir); int flags; int ret; unmount_to_daemon_mq_name = strcat_dup(slash, mount_dir_basename, prefix, u2d_suffix); if (!unmount_to_daemon_mq_name) { ERROR("Out of memory"); return WIMLIB_ERR_NOMEM; } daemon_to_unmount_mq_name = strcat_dup(slash, mount_dir_basename, prefix, d2u_suffix); if (!daemon_to_unmount_mq_name) { ERROR("Out of memory"); ret = WIMLIB_ERR_NOMEM; goto err1; } remove_trailing_slashes(unmount_to_daemon_mq_name); remove_trailing_slashes(daemon_to_unmount_mq_name); s_slashes_underscores_g(unmount_to_daemon_mq_name + 1); s_slashes_underscores_g(daemon_to_unmount_mq_name + 1); if (daemon) flags = O_RDONLY | O_CREAT; else flags = O_WRONLY | O_CREAT; unmount_to_daemon_mq = mq_open(unmount_to_daemon_mq_name, flags, 0700, NULL); if (unmount_to_daemon_mq == (mqd_t)-1) { ERROR_WITH_ERRNO("mq_open()"); ret = WIMLIB_ERR_MQUEUE; goto err2; } if (daemon) flags = O_WRONLY | O_CREAT; else flags = O_RDONLY | O_CREAT; daemon_to_unmount_mq = mq_open(daemon_to_unmount_mq_name, flags, 0700, NULL); if (daemon_to_unmount_mq == (mqd_t)-1) { ERROR_WITH_ERRNO("mq_open()"); ret = WIMLIB_ERR_MQUEUE; goto err3; } return 0; err3: mq_close(unmount_to_daemon_mq); mq_unlink(unmount_to_daemon_mq_name); err2: FREE(daemon_to_unmount_mq_name); err1: FREE(unmount_to_daemon_mq_name); return ret; } static int mq_get_msgsize(mqd_t mq) { static const char *msgsize_max_file = "/proc/sys/fs/mqueue/msgsize_max"; FILE *fp; struct mq_attr attr; int msgsize; if (mq_getattr(unmount_to_daemon_mq, &attr) == 0) { msgsize = attr.mq_msgsize; } else { ERROR_WITH_ERRNO("mq_getattr()"); ERROR("Attempting to read %s", msgsize_max_file); fp = fopen(msgsize_max_file, "rb"); if (fp) { if (fscanf(fp, "%d", &msgsize) != 1) { ERROR("Assuming message size of 8192"); msgsize = 8192; } fclose(fp); } else { ERROR_WITH_ERRNO("Failed to open the file `%s'", msgsize_max_file); ERROR("Assuming message size of 8192"); msgsize = 8192; } } return msgsize; } /* Closes the message queues, which are allocated in static variables */ static void close_message_queues() { mq_close(unmount_to_daemon_mq); mq_close(daemon_to_unmount_mq); mq_unlink(unmount_to_daemon_mq_name); mq_unlink(daemon_to_unmount_mq_name); } static int wimfs_access(const char *path, int mask) { /* Permissions not implemented */ return 0; } static int update_lte_of_staging_file(struct lookup_table_entry *lte, struct lookup_table *table) { struct lookup_table_entry *duplicate_lte; int ret; u8 hash[SHA1_HASH_SIZE]; struct stat stbuf; wimlib_assert(lte->resource_location == RESOURCE_IN_STAGING_FILE); wimlib_assert(lte->staging_file_name); ret = sha1sum(lte->staging_file_name, hash); if (ret != 0) return ret; lookup_table_unlink(table, lte); duplicate_lte = __lookup_resource(table, hash); if (duplicate_lte) { /* Merge duplicate lookup table entries */ duplicate_lte->refcnt += lte->refcnt; list_del(<e->staging_list); free_lookup_table_entry(lte); } else { if (stat(lte->staging_file_name, &stbuf) != 0) { ERROR_WITH_ERRNO("Failed to stat `%s'", lte->staging_file_name); return WIMLIB_ERR_STAT; } wimlib_assert(<e->file_on_disk == <e->staging_file_name); lte->resource_location = RESOURCE_IN_FILE_ON_DISK; copy_hash(lte->hash, hash); lte->resource_entry.original_size = stbuf.st_size; lte->resource_entry.size = stbuf.st_size; lte->lte_inode = NULL; lookup_table_insert(table, lte); } return 0; } static int inode_close_fds(struct inode *inode) { for (u16 i = 0, j = 0; j < inode->num_opened_fds; i++) { struct wimlib_fd *fd = inode->fds[i]; if (fd) { wimlib_assert(fd->f_inode == inode); int ret = close_wimlib_fd(fd); if (ret != 0) return ret; j++; } } return 0; } /*static int dentry_close_fds(struct dentry *dentry, void *ignore)*/ /*{*/ /*return inode_close_fds(dentry->d_inode);*/ /*}*/ /* Overwrites the WIM file, with changes saved. */ static int rebuild_wim(WIMStruct *w, bool check_integrity) { int ret; struct lookup_table_entry *lte, *tmp; DEBUG("Closing all staging file descriptors."); list_for_each_entry(lte, &staging_list, staging_list) { ret = inode_close_fds(lte->lte_inode); if (ret != 0) return ret; } /*ret = for_dentry_in_tree(wim_root_dentry(w), dentry_close_fds, NULL);*/ /*if (ret != 0)*/ /*return ret;*/ DEBUG("Calculating SHA1 checksums for all new staging files."); list_for_each_entry_safe(lte, tmp, &staging_list, staging_list) { ret = update_lte_of_staging_file(lte, w->lookup_table); if (ret != 0) return ret; } xml_update_image_info(w, w->current_image); ret = wimlib_overwrite(w, check_integrity); if (ret != 0) { ERROR("Failed to commit changes"); return ret; } return ret; } /* Called when the filesystem is unmounted. */ static void wimfs_destroy(void *p) { /* For read-write mounts, the `imagex unmount' command, which is * running in a separate process and is executing the * wimlib_unmount() function, will send this process a byte * through a message queue that indicates whether the --commit * option was specified or not. */ int msgsize; struct timespec timeout; struct timeval now; ssize_t bytes_received; int ret; char commit; char check_integrity; char status; ret = open_message_queues(true); if (ret != 0) exit(1); msgsize = mq_get_msgsize(unmount_to_daemon_mq); char msg[msgsize]; msg[0] = 0; msg[1] = 0; /* Wait at most 3 seconds before giving up and discarding changes. */ gettimeofday(&now, NULL); timeout.tv_sec = now.tv_sec + 3; timeout.tv_nsec = now.tv_usec * 1000; DEBUG("Waiting for message telling us whether to commit or not, and " "whether to include integrity checks."); bytes_received = mq_timedreceive(unmount_to_daemon_mq, msg, msgsize, NULL, &timeout); commit = msg[0]; check_integrity = msg[1]; if (bytes_received == -1) { if (errno == ETIMEDOUT) { ERROR("Timed out."); } else { ERROR_WITH_ERRNO("mq_timedreceive()"); } ERROR("Not committing."); } else { DEBUG("Received message: [%d %d]", msg[0], msg[1]); } status = 0; if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { if (commit) { status = chdir(working_directory); if (status != 0) { ERROR_WITH_ERRNO("chdir()"); status = WIMLIB_ERR_NOTDIR; goto done; } status = rebuild_wim(w, (check_integrity != 0)); } ret = delete_staging_dir(); if (ret != 0) { ERROR_WITH_ERRNO("Failed to delete the staging " "directory"); if (status == 0) status = ret; } } else { DEBUG("Read-only mount"); } done: DEBUG("Sending status %u", status); ret = mq_send(daemon_to_unmount_mq, &status, 1, 1); if (ret == -1) ERROR_WITH_ERRNO("Failed to send status to unmount process"); close_message_queues(); } #if 0 static int wimfs_fallocate(const char *path, int mode, off_t offset, off_t len, struct fuse_file_info *fi) { struct wimlib_fd *fd = (struct wimlib_fd*)(uintptr_t)fi->fh; wimlib_assert(fd->staging_fd != -1); return fallocate(fd->staging_fd, mode, offset, len); } #endif static int wimfs_fgetattr(const char *path, struct stat *stbuf, struct fuse_file_info *fi) { struct wimlib_fd *fd = (struct wimlib_fd*)(uintptr_t)fi->fh; return inode_to_stbuf(fd->f_inode, fd->lte, stbuf); } static int wimfs_ftruncate(const char *path, off_t size, struct fuse_file_info *fi) { struct wimlib_fd *fd = (struct wimlib_fd*)(uintptr_t)fi->fh; int ret = ftruncate(fd->staging_fd, size); if (ret != 0) return ret; if (fd->lte && size < fd->lte->resource_entry.original_size) fd->lte->resource_entry.original_size = size; return 0; } /* * Fills in a `struct stat' that corresponds to a file or directory in the WIM. */ static int wimfs_getattr(const char *path, struct stat *stbuf) { struct dentry *dentry; struct lookup_table_entry *lte; int ret; ret = lookup_resource(w, path, get_lookup_flags() | LOOKUP_FLAG_DIRECTORY_OK, &dentry, <e, NULL); if (ret != 0) return ret; return inode_to_stbuf(dentry->d_inode, lte, stbuf); } #ifdef ENABLE_XATTR /* Read an alternate data stream through the XATTR interface, or get its size */ static int wimfs_getxattr(const char *path, const char *name, char *value, size_t size) { int ret; struct dentry *dentry; struct ads_entry *ads_entry; size_t res_size; struct lookup_table_entry *lte; if (!(mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; if (strlen(name) < 5 || memcmp(name, "user.", 5) != 0) return -ENOATTR; name += 5; dentry = get_dentry(w, path); if (!dentry) return -ENOENT; ads_entry = inode_get_ads_entry(dentry->d_inode, name, NULL); if (!ads_entry) return -ENOATTR; lte = ads_entry->lte; res_size = wim_resource_size(lte); if (size == 0) return res_size; if (res_size > size) return -ERANGE; ret = read_full_wim_resource(lte, (u8*)value); if (ret != 0) return -EIO; return res_size; } #endif /* Create a hard link */ static int wimfs_link(const char *to, const char *from) { struct dentry *from_dentry, *from_dentry_parent; const char *link_name; struct inode *inode; struct lookup_table_entry *lte; inode = wim_pathname_to_inode(w, to); if (!inode) return -ENOENT; if (!inode_is_regular_file(inode)) return -EPERM; from_dentry_parent = get_parent_dentry(w, from); if (!from_dentry_parent) return -ENOENT; if (!dentry_is_directory(from_dentry_parent)) return -ENOTDIR; link_name = path_basename(from); if (get_dentry_child_with_name(from_dentry_parent, link_name)) return -EEXIST; from_dentry = new_dentry(link_name); if (!from_dentry) return -ENOMEM; inode_add_dentry(from_dentry, inode); from_dentry->d_inode = inode; inode->link_count++; for (unsigned i = 0; i <= inode->num_ads; i++) { lte = inode_stream_lte_resolved(inode, i); if (lte) lte->refcnt++; } link_dentry(from_dentry, from_dentry_parent); return 0; } #ifdef ENABLE_XATTR static int wimfs_listxattr(const char *path, char *list, size_t size) { struct dentry *dentry; int ret; char *p = list; size_t needed_size; unsigned i; struct inode *inode; if (!(mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; /* List alternate data streams, or get the list size */ ret = lookup_resource(w, path, get_lookup_flags(), &dentry, NULL, NULL); if (ret != 0) return ret; inode = dentry->d_inode; if (size == 0) { needed_size = 0; for (i = 0; i < inode->num_ads; i++) needed_size += inode->ads_entries[i].stream_name_utf8_len + 6; return needed_size; } else { for (i = 0; i < inode->num_ads; i++) { needed_size = inode->ads_entries[i].stream_name_utf8_len + 6; if (needed_size > size) return -ERANGE; p += sprintf(p, "user.%s", inode->ads_entries[i].stream_name_utf8) + 1; size -= needed_size; } return p - list; } } #endif /* * Create a directory in the WIM. * @mode is currently ignored. */ static int wimfs_mkdir(const char *path, mode_t mode) { struct dentry *parent; struct dentry *newdir; const char *basename; parent = get_parent_dentry(w, path); if (!parent) return -ENOENT; if (!dentry_is_directory(parent)) return -ENOTDIR; basename = path_basename(path); if (get_dentry_child_with_name(parent, basename)) return -EEXIST; newdir = new_dentry_with_inode(basename); newdir->d_inode->attributes |= FILE_ATTRIBUTE_DIRECTORY; newdir->d_inode->resolved = true; newdir->d_inode->ino = next_ino++; link_dentry(newdir, parent); return 0; } /* Creates a regular file. */ static int wimfs_mknod(const char *path, mode_t mode, dev_t rdev) { const char *stream_name; if ((mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS) && (stream_name = path_stream_name(path))) { /* Make an alternate data stream */ struct ads_entry *new_entry; struct dentry *dentry; char *p = (char*)stream_name - 1; wimlib_assert(*p == ':'); *p = '\0'; dentry = get_dentry(w, path); if (!dentry || !dentry_is_regular_file(dentry)) return -ENOENT; if (inode_get_ads_entry(dentry->d_inode, stream_name, NULL)) return -EEXIST; new_entry = inode_add_ads(dentry->d_inode, stream_name); if (!new_entry) return -ENOENT; } else { struct dentry *dentry, *parent; const char *basename; /* Make a normal file (not an alternate data stream) */ /* Make sure that the parent of @path exists and is a directory, and * that the dentry named by @path does not already exist. */ parent = get_parent_dentry(w, path); if (!parent) return -ENOENT; if (!dentry_is_directory(parent)) return -ENOTDIR; basename = path_basename(path); if (get_dentry_child_with_name(parent, path)) return -EEXIST; dentry = new_dentry_with_inode(basename); if (!dentry) return -ENOMEM; dentry->d_inode->resolved = true; dentry->d_inode->ino = next_ino++; link_dentry(dentry, parent); } return 0; } /* Open a file. */ static int wimfs_open(const char *path, struct fuse_file_info *fi) { struct dentry *dentry; struct lookup_table_entry *lte; int ret; struct wimlib_fd *fd; struct inode *inode; u16 stream_idx; u32 stream_id; ret = lookup_resource(w, path, get_lookup_flags(), &dentry, <e, &stream_idx); if (ret != 0) return ret; inode = dentry->d_inode; if (stream_idx == 0) stream_id = 0; else stream_id = inode->ads_entries[stream_idx - 1].stream_id; /* The file resource may be in the staging directory (read-write mounts * only) or in the WIM. If it's in the staging directory, we need to * open a native file descriptor for the corresponding file. Otherwise, * we can read the file resource directly from the WIM file if we are * opening it read-only, but we need to extract the resource to the * staging directory if we are opening it writable. */ if (flags_writable(fi->flags) && (!lte || lte->resource_location != RESOURCE_IN_STAGING_FILE)) { u64 size = (lte) ? wim_resource_size(lte) : 0; ret = extract_resource_to_staging_dir(inode, stream_id, <e, size); if (ret != 0) return ret; } ret = alloc_wimlib_fd(inode, stream_id, lte, &fd); if (ret != 0) return ret; if (lte && lte->resource_location == RESOURCE_IN_STAGING_FILE) { fd->staging_fd = open(lte->staging_file_name, fi->flags); if (fd->staging_fd == -1) { close_wimlib_fd(fd); return -errno; } } fi->fh = (uintptr_t)fd; return 0; } /* Opens a directory. */ static int wimfs_opendir(const char *path, struct fuse_file_info *fi) { struct inode *inode; int ret; struct wimlib_fd *fd = NULL; inode = wim_pathname_to_inode(w, path); if (!inode) return -ENOENT; if (!inode_is_directory(inode)) return -ENOTDIR; ret = alloc_wimlib_fd(inode, 0, NULL, &fd); fi->fh = (uintptr_t)fd; return ret; } /* * Read data from a file in the WIM or in the staging directory. */ static int wimfs_read(const char *path, char *buf, size_t size, off_t offset, struct fuse_file_info *fi) { struct wimlib_fd *fd = (struct wimlib_fd*)(uintptr_t)fi->fh; if (!fd) return -EBADF; if (!fd->lte) /* Empty stream with no lookup table entry */ return 0; if (fd->lte->resource_location == RESOURCE_IN_STAGING_FILE) { /* Read from staging file */ wimlib_assert(fd->lte->staging_file_name); wimlib_assert(fd->staging_fd != -1); ssize_t ret; DEBUG("Seek to offset %zu", offset); if (lseek(fd->staging_fd, offset, SEEK_SET) == -1) return -errno; ret = read(fd->staging_fd, buf, size); if (ret == -1) return -errno; return ret; } else { /* Read from WIM */ u64 res_size = wim_resource_size(fd->lte); if (offset > res_size) return -EOVERFLOW; size = min(size, res_size - offset); if (read_wim_resource(fd->lte, (u8*)buf, size, offset, false) != 0) return -EIO; return size; } } /* Fills in the entries of the directory specified by @path using the * FUSE-provided function @filler. */ static int wimfs_readdir(const char *path, void *buf, fuse_fill_dir_t filler, off_t offset, struct fuse_file_info *fi) { struct wimlib_fd *fd = (struct wimlib_fd*)(uintptr_t)fi->fh; struct inode *inode; struct dentry *child; if (!fd) return -EBADF; inode = fd->f_inode; filler(buf, ".", NULL, 0); filler(buf, "..", NULL, 0); child = inode->children; if (!child) return 0; do { if (filler(buf, child->file_name_utf8, NULL, 0)) return 0; child = child->next; } while (child != inode->children); return 0; } static int wimfs_readlink(const char *path, char *buf, size_t buf_len) { struct dentry *dentry = get_dentry(w, path); int ret; if (!dentry) return -ENOENT; if (!dentry_is_symlink(dentry)) return -EINVAL; ret = inode_readlink(dentry->d_inode, buf, buf_len, w); if (ret > 0) ret = 0; return ret; } /* Close a file. */ static int wimfs_release(const char *path, struct fuse_file_info *fi) { struct wimlib_fd *fd = (struct wimlib_fd*)(uintptr_t)fi->fh; return close_wimlib_fd(fd); } /* Close a directory */ static int wimfs_releasedir(const char *path, struct fuse_file_info *fi) { struct wimlib_fd *fd = (struct wimlib_fd*)(uintptr_t)fi->fh; return close_wimlib_fd(fd); } #ifdef ENABLE_XATTR /* Remove an alternate data stream through the XATTR interface */ static int wimfs_removexattr(const char *path, const char *name) { struct dentry *dentry; struct ads_entry *ads_entry; u16 ads_idx; if (!(mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; if (strlen(name) < 5 || memcmp(name, "user.", 5) != 0) return -ENOATTR; name += 5; dentry = get_dentry(w, path); if (!dentry) return -ENOENT; ads_entry = inode_get_ads_entry(dentry->d_inode, name, &ads_idx); if (!ads_entry) return -ENOATTR; inode_remove_ads(dentry->d_inode, ads_idx, w->lookup_table); return 0; } #endif /* Renames a file or directory. See rename (3) */ static int wimfs_rename(const char *from, const char *to) { struct dentry *src; struct dentry *dst; struct dentry *parent_of_dst; char *file_name_utf16 = NULL, *file_name_utf8 = NULL; u16 file_name_utf16_len, file_name_utf8_len; int ret; /* This rename() implementation currently only supports actual files * (not alternate data streams) */ src = get_dentry(w, from); if (!src) return -ENOENT; dst = get_dentry(w, to); ret = get_names(&file_name_utf16, &file_name_utf8, &file_name_utf16_len, &file_name_utf8_len, path_basename(to)); if (ret != 0) return -ENOMEM; if (dst) { /* Destination file exists */ if (src == dst) /* Same file */ return 0; if (!dentry_is_directory(src)) { /* Cannot rename non-directory to directory. */ if (dentry_is_directory(dst)) return -EISDIR; } else { /* Cannot rename directory to a non-directory or a non-empty * directory */ if (!dentry_is_directory(dst)) return -ENOTDIR; if (dst->d_inode->children != NULL) return -ENOTEMPTY; } parent_of_dst = dst->parent; remove_dentry(dst, w->lookup_table); } else { /* Destination does not exist */ parent_of_dst = get_parent_dentry(w, to); if (!parent_of_dst) return -ENOENT; if (!dentry_is_directory(parent_of_dst)) return -ENOTDIR; } FREE(src->file_name); FREE(src->file_name_utf8); src->file_name = file_name_utf16; src->file_name_utf8 = file_name_utf8; src->file_name_len = file_name_utf16_len; src->file_name_utf8_len = file_name_utf8_len; unlink_dentry(src); link_dentry(src, parent_of_dst); return 0; } /* Remove a directory */ static int wimfs_rmdir(const char *path) { struct dentry *dentry; dentry = get_dentry(w, path); if (!dentry) return -ENOENT; if (!dentry_is_empty_directory(dentry)) return -ENOTEMPTY; remove_dentry(dentry, w->lookup_table); return 0; } #ifdef ENABLE_XATTR /* Write an alternate data stream through the XATTR interface */ static int wimfs_setxattr(const char *path, const char *name, const char *value, size_t size, int flags) { struct ads_entry *existing_ads_entry; struct ads_entry *new_ads_entry; struct lookup_table_entry *existing_lte; struct lookup_table_entry *lte; struct inode *inode; u8 value_hash[SHA1_HASH_SIZE]; u16 ads_idx; if (!(mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; if (strlen(name) < 5 || memcmp(name, "user.", 5) != 0) return -ENOATTR; name += 5; inode = wim_pathname_to_inode(w, path); if (!inode) return -ENOENT; existing_ads_entry = inode_get_ads_entry(inode, name, &ads_idx); if (existing_ads_entry) { if (flags & XATTR_CREATE) return -EEXIST; inode_remove_ads(inode, ads_idx, w->lookup_table); } else { if (flags & XATTR_REPLACE) return -ENOATTR; } new_ads_entry = inode_add_ads(inode, name); if (!new_ads_entry) return -ENOMEM; sha1_buffer((const u8*)value, size, value_hash); existing_lte = __lookup_resource(w->lookup_table, value_hash); if (existing_lte) { lte = existing_lte; lte->refcnt++; } else { u8 *value_copy; lte = new_lookup_table_entry(); if (!lte) return -ENOMEM; value_copy = MALLOC(size); if (!value_copy) { FREE(lte); return -ENOMEM; } memcpy(value_copy, value, size); lte->resource_location = RESOURCE_IN_ATTACHED_BUFFER; lte->attached_buffer = value_copy; lte->resource_entry.original_size = size; lte->resource_entry.size = size; lte->resource_entry.flags = 0; copy_hash(lte->hash, value_hash); lookup_table_insert(w->lookup_table, lte); } new_ads_entry->lte = lte; return 0; } #endif static int wimfs_symlink(const char *to, const char *from) { struct dentry *dentry_parent, *dentry; const char *link_name; struct inode *inode; dentry_parent = get_parent_dentry(w, from); if (!dentry_parent) return -ENOENT; if (!dentry_is_directory(dentry_parent)) return -ENOTDIR; link_name = path_basename(from); if (get_dentry_child_with_name(dentry_parent, link_name)) return -EEXIST; dentry = new_dentry_with_inode(link_name); if (!dentry) return -ENOMEM; inode = dentry->d_inode; inode->attributes = FILE_ATTRIBUTE_REPARSE_POINT; inode->reparse_tag = WIM_IO_REPARSE_TAG_SYMLINK; inode->ino = next_ino++; inode->resolved = true; if (inode_set_symlink(inode, to, w->lookup_table, NULL) != 0) goto out_free_dentry; link_dentry(dentry, dentry_parent); return 0; out_free_dentry: free_dentry(dentry); return -ENOMEM; } /* Reduce the size of a file */ static int wimfs_truncate(const char *path, off_t size) { struct dentry *dentry; struct lookup_table_entry *lte; int ret; u16 stream_idx; u32 stream_id; struct inode *inode; ret = lookup_resource(w, path, get_lookup_flags(), &dentry, <e, &stream_idx); if (ret != 0) return ret; if (!lte) /* Already a zero-length file */ return 0; inode = dentry->d_inode; if (stream_idx == 0) stream_id = 0; else stream_id = inode->ads_entries[stream_idx - 1].stream_id; if (lte->resource_location == RESOURCE_IN_STAGING_FILE) { wimlib_assert(lte->staging_file_name); ret = truncate(lte->staging_file_name, size); if (ret != 0) return -errno; lte->resource_entry.original_size = size; } else { wimlib_assert(lte->resource_location == RESOURCE_IN_WIM); /* File in WIM. Extract it to the staging directory, but only * the first @size bytes of it. */ ret = extract_resource_to_staging_dir(inode, stream_id, <e, size); } return ret; } /* Remove a regular file */ static int wimfs_unlink(const char *path) { struct dentry *dentry; struct lookup_table_entry *lte; struct inode *inode; int ret; u16 stream_idx; unsigned i; ret = lookup_resource(w, path, get_lookup_flags(), &dentry, <e, &stream_idx); if (ret != 0) return ret; if (stream_idx == 0) remove_dentry(dentry, w->lookup_table); else inode_remove_ads(dentry->d_inode, stream_idx - 1, w->lookup_table); return 0; } #ifdef HAVE_UTIMENSAT /* * Change the timestamp on a file dentry. * * Note that alternate data streams do not have their own timestamps. */ static int wimfs_utimens(const char *path, const struct timespec tv[2]) { struct dentry *dentry; struct inode *inode; dentry = get_dentry(w, path); if (!dentry) return -ENOENT; inode = dentry->d_inode; if (tv[0].tv_nsec != UTIME_OMIT) { if (tv[0].tv_nsec == UTIME_NOW) inode->last_access_time = get_wim_timestamp(); else inode->last_access_time = timespec_to_wim_timestamp(&tv[0]); } if (tv[1].tv_nsec != UTIME_OMIT) { if (tv[1].tv_nsec == UTIME_NOW) inode->last_write_time = get_wim_timestamp(); else inode->last_write_time = timespec_to_wim_timestamp(&tv[1]); } return 0; } #else static int wimfs_utime(const char *path, struct utimbuf *times) { struct dentry *dentry; struct inode *inode; dentry = get_dentry(w, path); if (!dentry) return -ENOENT; inode = dentry->d_inode; inode->last_write_time = unix_timestamp_to_wim(times->modtime); inode->last_access_time = unix_timestamp_to_wim(times->actime); return 0; } #endif /* Writes to a file in the WIM filesystem. * It may be an alternate data stream, but here we don't even notice because we * just get a lookup table entry. */ static int wimfs_write(const char *path, const char *buf, size_t size, off_t offset, struct fuse_file_info *fi) { struct wimlib_fd *fd = (struct wimlib_fd*)(uintptr_t)fi->fh; int ret; u64 now; if (!fd) return -EBADF; wimlib_assert(fd->lte); wimlib_assert(fd->lte->staging_file_name); wimlib_assert(fd->staging_fd != -1); wimlib_assert(fd->f_inode); /* Seek to the requested position */ if (lseek(fd->staging_fd, offset, SEEK_SET) == -1) return -errno; /* Write the data. */ ret = write(fd->staging_fd, buf, size); if (ret == -1) return -errno; now = get_wim_timestamp(); fd->f_inode->last_write_time = now; fd->f_inode->last_access_time = now; return ret; } static struct fuse_operations wimfs_operations = { .access = wimfs_access, .destroy = wimfs_destroy, #if 0 .fallocate = wimfs_fallocate, #endif .fgetattr = wimfs_fgetattr, .ftruncate = wimfs_ftruncate, .getattr = wimfs_getattr, #ifdef ENABLE_XATTR .getxattr = wimfs_getxattr, #endif .link = wimfs_link, #ifdef ENABLE_XATTR .listxattr = wimfs_listxattr, #endif .mkdir = wimfs_mkdir, .mknod = wimfs_mknod, .open = wimfs_open, .opendir = wimfs_opendir, .read = wimfs_read, .readdir = wimfs_readdir, .readlink = wimfs_readlink, .release = wimfs_release, .releasedir = wimfs_releasedir, #ifdef ENABLE_XATTR .removexattr = wimfs_removexattr, #endif .rename = wimfs_rename, .rmdir = wimfs_rmdir, #ifdef ENABLE_XATTR .setxattr = wimfs_setxattr, #endif .symlink = wimfs_symlink, .truncate = wimfs_truncate, .unlink = wimfs_unlink, #ifdef HAVE_UTIMENSAT .utimens = wimfs_utimens, #else .utime = wimfs_utime, #endif .write = wimfs_write, }; /* Mounts a WIM file. */ WIMLIBAPI int wimlib_mount(WIMStruct *wim, int image, const char *dir, int flags, WIMStruct **additional_swms, unsigned num_additional_swms) { int argc = 0; char *argv[16]; int ret; char *p; struct lookup_table *joined_tab, *wim_tab_save; struct image_metadata *imd; DEBUG("Mount: wim = %p, image = %d, dir = %s, flags = %d, ", wim, image, dir, flags); if (!wim || !dir) return WIMLIB_ERR_INVALID_PARAM; ret = verify_swm_set(wim, additional_swms, num_additional_swms); if (ret != 0) return ret; if (num_additional_swms) { ret = new_joined_lookup_table(wim, additional_swms, num_additional_swms, &joined_tab); if (ret != 0) return ret; wim_tab_save = wim->lookup_table; wim->lookup_table = joined_tab; } ret = wimlib_select_image(wim, image); if (ret != 0) goto out; imd = &wim->image_metadata[image - 1]; DEBUG("Selected image %d", image); next_ino = assign_inode_numbers(&imd->inode_list); DEBUG("(next_ino = %"PRIu64")", next_ino); /* Resolve all the lookup table entries of the dentry tree */ DEBUG("Resolving lookup table entries"); for_dentry_in_tree(imd->root_dentry, dentry_resolve_ltes, wim->lookup_table); if (flags & WIMLIB_MOUNT_FLAG_READWRITE) imd->modified = true; if (!(flags & (WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_NONE | WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR | WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS))) flags |= WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR; DEBUG("Getting current directory"); mount_dir = dir; working_directory = getcwd(NULL, 0); if (!working_directory) { ERROR_WITH_ERRNO("Could not determine current directory"); ret = WIMLIB_ERR_NOTDIR; goto out; } DEBUG("Closing POSIX message queues"); /* XXX hack to get rid of the message queues if they already exist for * some reason (maybe left over from a previous mount that wasn't * unmounted correctly) */ ret = open_message_queues(true); if (ret != 0) goto out; close_message_queues(); DEBUG("Preparing arguments to fuse_main()"); p = STRDUP(dir); if (!p) { ret = WIMLIB_ERR_NOMEM; goto out; } argv[argc++] = "imagex"; argv[argc++] = p; argv[argc++] = "-s"; /* disable multi-threaded operation */ if (flags & WIMLIB_MOUNT_FLAG_DEBUG) argv[argc++] = "-d"; /* * We provide the use_ino option because we are going to assign inode * numbers oursides. We've already numbered the inodes with unique * numbers in the assign_inode_numbers() function, and the static * variable next_ino is set to the next available inode number. */ char optstring[256] = "use_ino,subtype=wimfs,attr_timeout=0"; argv[argc++] = "-o"; argv[argc++] = optstring; if ((flags & WIMLIB_MOUNT_FLAG_READWRITE)) { /* Read-write mount. Make the staging directory */ make_staging_dir(); if (!staging_dir_name) { FREE(p); ret = WIMLIB_ERR_MKDIR; goto out; } } else { /* Read-only mount */ strcat(optstring, ",ro"); } argv[argc] = NULL; #ifdef ENABLE_DEBUG { int i; DEBUG("FUSE command line (argc = %d): ", argc); for (i = 0; i < argc; i++) { fputs(argv[i], stdout); putchar(' '); } putchar('\n'); fflush(stdout); } #endif /* Set static variables. */ w = wim; mount_flags = flags; ret = fuse_main(argc, argv, &wimfs_operations, NULL); if (ret) ret = WIMLIB_ERR_FUSE; out: if (num_additional_swms) { free_lookup_table(wim->lookup_table); wim->lookup_table = wim_tab_save; } return ret; } /* * Unmounts the WIM file that was previously mounted on @dir by using * wimlib_mount(). */ WIMLIBAPI int wimlib_unmount(const char *dir, int flags) { pid_t pid; int status; int ret; char msg[2]; struct timeval now; struct timespec timeout; int msgsize; int errno_save; mount_dir = dir; /* Open message queues between the unmount process and the * filesystem daemon. */ ret = open_message_queues(false); if (ret != 0) return ret; /* Send a message to the filesystem saying whether to commit or * not. */ msg[0] = (flags & WIMLIB_UNMOUNT_FLAG_COMMIT) ? 1 : 0; msg[1] = (flags & WIMLIB_UNMOUNT_FLAG_CHECK_INTEGRITY) ? 1 : 0; DEBUG("Sending message: %s, %s", (msg[0] == 0) ? "don't commit" : "commit", (msg[1] == 0) ? "don't check" : "check"); ret = mq_send(unmount_to_daemon_mq, msg, 2, 1); if (ret == -1) { ERROR("Failed to notify filesystem daemon whether we want to " "commit changes or not"); close_message_queues(); return WIMLIB_ERR_MQUEUE; } /* Execute `fusermount -u', which is installed setuid root, to unmount * the WIM. * * FUSE does not yet implement synchronous unmounts. This means that * fusermount -u will return before the filesystem daemon returns from * wimfs_destroy(). This is partly what we want, because we need to * send a message from this process to the filesystem daemon telling * whether --commit was specified or not. However, after that, the * unmount process must wait for the filesystem daemon to finish writing * the WIM file. */ pid = fork(); if (pid == -1) { ERROR_WITH_ERRNO("Failed to fork()"); return WIMLIB_ERR_FORK; } if (pid == 0) { execlp("fusermount", "fusermount", "-u", dir, NULL); ERROR_WITH_ERRNO("Failed to execute `fusermount'"); exit(WIMLIB_ERR_FUSERMOUNT); } ret = wait(&status); if (ret == -1) { ERROR_WITH_ERRNO("Failed to wait for fusermount process to " "terminate"); return WIMLIB_ERR_FUSERMOUNT; } if (status != 0) { ERROR("fusermount exited with status %d", status); /* Try again, but with the `umount' program. This is required * on other FUSE implementations such as FreeBSD's that do not * have a `fusermount' program. */ pid = fork(); if (pid == -1) { ERROR_WITH_ERRNO("Failed to fork()"); return WIMLIB_ERR_FORK; } if (pid == 0) { execlp("umount", "umount", dir, NULL); ERROR_WITH_ERRNO("Failed to execute `umount'"); exit(WIMLIB_ERR_FUSERMOUNT); } ret = wait(&status); if (ret == -1) { ERROR_WITH_ERRNO("Failed to wait for `umount' process to " "terminate"); return WIMLIB_ERR_FUSERMOUNT; } if (status != 0) { ERROR("`umount' exited with failure status"); return WIMLIB_ERR_FUSERMOUNT; } } /* Wait for a message from the filesytem daemon indicating whether the * filesystem was unmounted successfully (0) or an error occurred (1). * This may take a long time if a big WIM file needs to be rewritten. */ /* Wait at most 600??? seconds before giving up and returning false. * Either it's a really big WIM file, or (more likely) the * filesystem daemon has crashed or failed for some reason. * * XXX come up with some method to determine if the filesystem * daemon has really crashed or not. * * XXX Idea: have mount daemon write its PID into the WIM file header? * */ gettimeofday(&now, NULL); timeout.tv_sec = now.tv_sec + 600; timeout.tv_nsec = now.tv_usec * 1000; msgsize = mq_get_msgsize(daemon_to_unmount_mq); char mailbox[msgsize]; mailbox[0] = 0; DEBUG("Waiting for message telling us whether the unmount was " "successful or not."); ret = mq_timedreceive(daemon_to_unmount_mq, mailbox, msgsize, NULL, &timeout); errno_save = errno; close_message_queues(); if (ret == -1) { if (errno_save == ETIMEDOUT) { ERROR("Timed out- probably the filesystem daemon " "crashed and the WIM was not written " "successfully."); return WIMLIB_ERR_TIMEOUT; } else { ERROR("mq_receive(): %s", strerror(errno_save)); return WIMLIB_ERR_MQUEUE; } } DEBUG("Received message: %s", (mailbox[0] == 0) ? "Unmount OK" : "Unmount Failed"); if (mailbox[0] != 0) ERROR("Unmount failed"); return mailbox[0]; } #else /* WITH_FUSE */ static inline int mount_unsupported_error() { ERROR("WIMLIB was compiled with --without-fuse, which disables support " "for mounting WIMs."); return WIMLIB_ERR_UNSUPPORTED; } WIMLIBAPI int wimlib_unmount(const char *dir, int flags) { return mount_unsupported_error(); } WIMLIBAPI int wimlib_mount(WIMStruct *wim_p, int image, const char *dir, int flags, WIMStruct **additional_swms, unsigned num_additional_swms) { return mount_unsupported_error(); } #endif /* WITH_FUSE */