/* * mount_image.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 "buffer_io.h" #include "timestamp.h" #include #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 *f_lte; int staging_fd; u16 idx; u32 stream_id; }; struct wimfs_context { /* The WIMStruct for the mounted WIM. */ WIMStruct *wim; /* 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. */ char *staging_dir_name; size_t staging_dir_name_len; /* Flags passed to wimlib_mount(). */ int mount_flags; /* Next inode number to be assigned. */ u64 next_ino; /* List of lookup table entries in the staging directory */ struct list_head staging_list; /* 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 */ char *unmount_to_daemon_mq_name; char *daemon_to_unmount_mq_name; mqd_t unmount_to_daemon_mq; mqd_t daemon_to_unmount_mq; }; static void init_wimfs_context(struct wimfs_context *ctx) { memset(ctx, 0, sizeof(*ctx)); ctx->unmount_to_daemon_mq = (mqd_t)-1; ctx->daemon_to_unmount_mq = (mqd_t)-1; INIT_LIST_HEAD(&ctx->staging_list); } static inline struct wimfs_context *wimfs_get_context() { return (struct wimfs_context*)fuse_get_context()->private_data; } static inline WIMStruct *wimfs_get_WIMStruct() { return wimfs_get_context()->wim; } static inline bool wimfs_ctx_readonly(const struct wimfs_context *ctx) { return (ctx->mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) == 0; } static inline int get_lookup_flags(const struct wimfs_context *ctx) { if (ctx->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. * @readonly: True if this is a read-only mount. * * 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, bool readonly) { static const u16 fds_per_alloc = 8; static const u16 max_fds = 0xffff; int ret; pthread_mutex_lock(&inode->i_mutex); 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) { ret = -EMFILE; goto out; } 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) { ret = -ENOMEM; goto out; } 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) { ret = -ENOMEM; break; } fd->f_inode = inode; fd->f_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 && !readonly) lte->num_opened_fds++; DEBUG("Allocated fd (idx = %u)", fd->idx); ret = 0; break; } } out: pthread_mutex_unlock(&inode->i_mutex); return ret; } static void inode_put_fd(struct inode *inode, struct wimlib_fd *fd) { wimlib_assert(fd != NULL); wimlib_assert(inode != NULL); pthread_mutex_lock(&inode->i_mutex); wimlib_assert(fd->f_inode == inode); wimlib_assert(inode->num_opened_fds != 0); wimlib_assert(fd->idx < inode->num_allocated_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) { pthread_mutex_unlock(&inode->i_mutex); free_inode(inode); } else { pthread_mutex_unlock(&inode->i_mutex); } } static int lte_put_fd(struct lookup_table_entry *lte, struct wimlib_fd *fd) { wimlib_assert(fd != NULL); wimlib_assert(fd->f_lte == lte); if (!lte) /* Empty stream with no lookup table entry */ return 0; /* Close staging file descriptor if needed. */ if (lte->resource_location == RESOURCE_IN_STAGING_FILE && 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); return 0; } /* Close a file descriptor. */ static int close_wimlib_fd(struct wimlib_fd *fd) { int ret; wimlib_assert(fd != NULL); 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->f_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, struct wimfs_context *ctx) { size_t name_len; char *name; struct stat stbuf; int fd; int errno_save; name_len = ctx->staging_dir_name_len + 1 + SHA1_HASH_SIZE; name = MALLOC(name_len + 1); if (!name) { errno = ENOMEM; return -1; } do { memcpy(name, ctx->staging_dir_name, ctx->staging_dir_name_len); name[ctx->staging_dir_name_len] = '/'; randomize_char_array_with_alnum(name + ctx->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, struct wimfs_context *ctx) { char *staging_file_name; int ret; int fd; struct lookup_table_entry *old_lte, *new_lte; DEBUG("Extracting resource to staging dir: inode %"PRIu64", " "stream id %"PRIu32, inode->ino, stream_id); old_lte = *lte; fd = create_staging_file(&staging_file_name, O_WRONLY, ctx); 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(ctx->wim->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 = %u, 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->f_lte == old_lte); wimlib_assert(fd->staging_fd == -1); fd->f_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("%hu 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->resource_location = RESOURCE_IN_STAGING_FILE; new_lte->staging_file_name = staging_file_name; 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(ctx->wim->lookup_table, new_lte); list_add(&new_lte->staging_list, &ctx->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->f_lte == new_lte) { fd->f_lte = old_lte; if (fd->staging_fd != -1) { close(fd->staging_fd); fd->staging_fd = -1; } j++; } } 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 saves its name in the * filesystem context structure. */ static int make_staging_dir(struct wimfs_context *ctx, const char *user_prefix) { static const size_t random_suffix_len = 10; static const char *common_suffix = ".staging"; static const size_t common_suffix_len = 8; char *staging_dir_name = NULL; size_t staging_dir_name_len; size_t prefix_len; const char *wim_basename; char *real_user_prefix = NULL; int ret; if (user_prefix) { real_user_prefix = realpath(user_prefix, NULL); if (!real_user_prefix) { ERROR_WITH_ERRNO("Could not resolve `%s'", real_user_prefix); ret = WIMLIB_ERR_NOTDIR; goto out; } wim_basename = path_basename(ctx->wim->filename); prefix_len = strlen(real_user_prefix) + 1 + strlen(wim_basename); } else { prefix_len = strlen(ctx->wim->filename); } staging_dir_name_len = prefix_len + common_suffix_len + random_suffix_len; staging_dir_name = MALLOC(staging_dir_name_len + 1); if (!staging_dir_name) { ret = WIMLIB_ERR_NOMEM; goto out; } if (real_user_prefix) sprintf(staging_dir_name, "%s/%s", real_user_prefix, wim_basename); else strcpy(staging_dir_name, ctx->wim->filename); strcat(staging_dir_name, common_suffix); randomize_char_array_with_alnum(staging_dir_name + prefix_len + common_suffix_len, random_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); ret = WIMLIB_ERR_MKDIR; } else { ret = 0; } out: FREE(real_user_prefix); if (ret == 0) { ctx->staging_dir_name = staging_dir_name; ctx->staging_dir_name_len = staging_dir_name_len; } else { FREE(staging_dir_name); } return ret; } 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 { ERROR_WITH_ERRNO("Cannot remove `%s'", fpath); return WIMLIB_ERR_DELETE_STAGING_DIR; } } /* * Deletes the staging directory and all the files contained in it. */ static int delete_staging_dir(struct wimfs_context *ctx) { int ret; wimlib_assert(ctx->staging_dir_name != NULL); ret = nftw(ctx->staging_dir_name, remove_file_or_directory, 10, FTW_DEPTH); FREE(ctx->staging_dir_name); ctx->staging_dir_name = NULL; return ret; } /* Simple function that returns the concatenation of 2 strings. */ static char *strcat_dup(const char *s1, const char *s2, size_t max_len) { size_t len = strlen(s1) + strlen(s2); if (len > max_len) len = max_len; char *p = MALLOC(len + 1); if (!p) return NULL; snprintf(p, len + 1, "%s%s", s1, s2); return p; } static int set_message_queue_names(struct wimfs_context *ctx, const char *mount_dir) { static const char *u2d_prefix = "/wimlib-unmount-to-daemon-mq"; static const char *d2u_prefix = "/wimlib-daemon-to-unmount-mq"; char *dir_path; char *p; int ret; dir_path = realpath(mount_dir, NULL); if (!dir_path) { ERROR_WITH_ERRNO("Failed to resolve path \"%s\"", mount_dir); return WIMLIB_ERR_NOTDIR; } DEBUG("Using absolute dir_path = `%s'", dir_path); p = dir_path; while (*p) { if (*p == '/') *p = 0xff; p++; } ctx->unmount_to_daemon_mq_name = strcat_dup(u2d_prefix, dir_path, NAME_MAX); if (!ctx->unmount_to_daemon_mq_name) { ret = WIMLIB_ERR_NOMEM; goto out_free_dir_path; } ctx->daemon_to_unmount_mq_name = strcat_dup(d2u_prefix, dir_path, NAME_MAX); if (!ctx->daemon_to_unmount_mq_name) { ret = WIMLIB_ERR_NOMEM; goto out_free_unmount_to_daemon_mq_name; } ret = 0; goto out_free_dir_path; out_free_unmount_to_daemon_mq_name: FREE(ctx->unmount_to_daemon_mq_name); ctx->unmount_to_daemon_mq_name = NULL; out_free_dir_path: FREE(dir_path); return ret; } static void free_message_queue_names(struct wimfs_context *ctx) { FREE(ctx->unmount_to_daemon_mq_name); FREE(ctx->daemon_to_unmount_mq_name); ctx->unmount_to_daemon_mq_name = NULL; ctx->daemon_to_unmount_mq_name = NULL; } /* * 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(struct wimfs_context *ctx, bool daemon) { int flags; int ret; wimlib_assert(ctx->unmount_to_daemon_mq_name != NULL && ctx->daemon_to_unmount_mq_name != NULL); if (daemon) flags = O_RDONLY | O_CREAT; else flags = O_WRONLY | O_CREAT; DEBUG("Opening message queue \"%s\"", ctx->unmount_to_daemon_mq_name); ctx->unmount_to_daemon_mq = mq_open(ctx->unmount_to_daemon_mq_name, flags, 0700, NULL); if (ctx->unmount_to_daemon_mq == (mqd_t)-1) { ERROR_WITH_ERRNO("mq_open()"); ret = WIMLIB_ERR_MQUEUE; goto out; } if (daemon) flags = O_WRONLY | O_CREAT; else flags = O_RDONLY | O_CREAT; DEBUG("Opening message queue \"%s\"", ctx->daemon_to_unmount_mq_name); ctx->daemon_to_unmount_mq = mq_open(ctx->daemon_to_unmount_mq_name, flags, 0700, NULL); if (ctx->daemon_to_unmount_mq == (mqd_t)-1) { ERROR_WITH_ERRNO("mq_open()"); ret = WIMLIB_ERR_MQUEUE; goto out_close_unmount_to_daemon_mq; } ret = 0; goto out; out_close_unmount_to_daemon_mq: mq_close(ctx->unmount_to_daemon_mq); mq_unlink(ctx->unmount_to_daemon_mq_name); ctx->unmount_to_daemon_mq = (mqd_t)-1; out: return ret; } /* Try to determine the maximum message size of a message queue. The return * value is the maximum message size, or a guess of 8192 bytes if it cannot be * determined. */ static long mq_get_msgsize(mqd_t mq) { static const char *msgsize_max_file = "/proc/sys/fs/mqueue/msgsize_max"; FILE *fp; struct mq_attr attr; long msgsize; if (mq_getattr(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, "%ld", &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; } static int get_mailbox(mqd_t mq, long needed_msgsize, long *msgsize_ret, char **mailbox_ret) { long msgsize; char *mailbox; msgsize = mq_get_msgsize(mq); if (msgsize < needed_msgsize) { ERROR("Message queue max size must be at least %ld!", needed_msgsize); return WIMLIB_ERR_MQUEUE; } mailbox = MALLOC(msgsize); if (!mailbox) { ERROR("Failed to allocate %ld bytes for mailbox", msgsize); return WIMLIB_ERR_NOMEM; } *msgsize_ret = msgsize; *mailbox_ret = mailbox; return 0; } static void unlink_message_queues(struct wimfs_context *ctx) { mq_unlink(ctx->unmount_to_daemon_mq_name); mq_unlink(ctx->daemon_to_unmount_mq_name); } /* Closes the message queues, which are allocated in static variables */ static void close_message_queues(struct wimfs_context *ctx) { mq_close(ctx->unmount_to_daemon_mq); ctx->unmount_to_daemon_mq = (mqd_t)(-1); mq_close(ctx->daemon_to_unmount_mq); ctx->daemon_to_unmount_mq = (mqd_t)(-1); unlink_message_queues(ctx); } static int wimfs_access(const char *path, int mask) { /* Permissions not implemented */ return 0; } static int wimfs_chmod(const char *path, mode_t mask) { struct dentry *dentry; struct wimfs_context *ctx = wimfs_get_context(); struct inode *inode; struct stat stbuf; int ret; ret = lookup_resource(ctx->wim, path, get_lookup_flags(ctx) | LOOKUP_FLAG_DIRECTORY_OK, &dentry, NULL, NULL); if (ret != 0) return ret; inode = dentry->d_inode; inode_to_stbuf(inode, NULL, &stbuf); if (mask == stbuf.st_mode) return 0; else return -EPERM; } static void inode_update_lte_ptr(struct inode *inode, struct lookup_table_entry *old_lte, struct lookup_table_entry *new_lte) { if (inode->lte == old_lte) { inode->lte = new_lte; } else { for (unsigned i = 0; i < inode->num_ads; i++) { if (inode->ads_entries[i].lte == old_lte) { inode->ads_entries[i].lte = new_lte; break; } } } } 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); inode_update_lte_ptr(lte->lte_inode, lte, duplicate_lte); 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; } if (stbuf.st_size == 0) { /* Zero-length stream. No lookup table entry needed. */ inode_update_lte_ptr(lte->lte_inode, lte, NULL); free_lookup_table_entry(lte); } else { wimlib_assert(<e->file_on_disk == <e->staging_file_name); lte->resource_entry.original_size = stbuf.st_size; lte->resource_entry.size = stbuf.st_size; lte->resource_location = RESOURCE_IN_FILE_ON_DISK; lte->lte_inode = NULL; copy_hash(lte->hash, hash); lookup_table_insert(table, lte); } } return 0; } static int inode_close_fds(struct inode *inode) { u16 num_opened_fds = inode->num_opened_fds; for (u16 i = 0, j = 0; j < 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; } /* Overwrites the WIM file, with changes saved. */ static int rebuild_wim(struct wimfs_context *ctx, int write_flags) { int ret; struct lookup_table_entry *lte, *tmp; WIMStruct *w = ctx->wim; DEBUG("Closing all staging file descriptors."); list_for_each_entry_safe(lte, tmp, &ctx->staging_list, staging_list) { ret = inode_close_fds(lte->lte_inode); if (ret != 0) return ret; } DEBUG("Calculating SHA1 checksums for all new staging files."); list_for_each_entry_safe(lte, tmp, &ctx->staging_list, staging_list) { ret = update_lte_of_staging_file(lte, ctx->wim->lookup_table); if (ret != 0) return ret; } xml_update_image_info(w, w->current_image); ret = wimlib_overwrite(w, write_flags, 0, NULL); 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. */ long msgsize; struct timespec timeout; struct timeval now; ssize_t bytes_received; int ret; char commit; char check_integrity; char status; char *mailbox; struct wimfs_context *ctx = wimfs_get_context(); int write_flags; if (open_message_queues(ctx, true)) return; if (get_mailbox(ctx->unmount_to_daemon_mq, 2, &msgsize, &mailbox)) goto out_close_message_queues; /* 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(ctx->unmount_to_daemon_mq, mailbox, msgsize, NULL, &timeout); if (bytes_received == -1) { ERROR_WITH_ERRNO("mq_timedreceive()"); ERROR("Not committing."); commit = 0; check_integrity = 0; } else { DEBUG("Received message: [%d %d]", mailbox[0], mailbox[1]); commit = mailbox[0]; check_integrity = mailbox[1]; } status = 0; if (ctx->mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { if (commit) { if (check_integrity) write_flags = WIMLIB_WRITE_FLAG_CHECK_INTEGRITY; else write_flags = 0; status = rebuild_wim(ctx, write_flags); } ret = delete_staging_dir(ctx); if (ret != 0) { ERROR("Failed to delete the staging directory"); if (status == 0) status = ret; } } else { DEBUG("Read-only mount"); } DEBUG("Sending status %hhd", status); ret = mq_send(ctx->daemon_to_unmount_mq, &status, 1, 1); if (ret == -1) ERROR_WITH_ERRNO("Failed to send status to unmount process"); FREE(mailbox); out_close_message_queues: close_message_queues(ctx); } #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->f_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 -errno; if (fd->f_lte && size < fd->f_lte->resource_entry.original_size) fd->f_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; struct wimfs_context *ctx = wimfs_get_context(); ret = lookup_resource(ctx->wim, path, get_lookup_flags(ctx) | 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 inode *inode; struct ads_entry *ads_entry; size_t res_size; struct lookup_table_entry *lte; struct wimfs_context *ctx = wimfs_get_context(); if (!(ctx->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(ctx->wim, path); if (!inode) return -ENOENT; ads_entry = inode_get_ads_entry(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, WIMLIB_RESOURCE_FLAG_MULTITHREADED); 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; WIMStruct *w = wimfs_get_WIMStruct(); 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++; } dentry_add_child(from_dentry_parent, from_dentry); return 0; } #ifdef ENABLE_XATTR static int wimfs_listxattr(const char *path, char *list, size_t size) { size_t needed_size; struct inode *inode; struct wimfs_context *ctx = wimfs_get_context(); if (!(ctx->mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) return -ENOTSUP; /* List alternate data streams, or get the list size */ inode = wim_pathname_to_inode(ctx->wim, path); if (!inode) return -ENOENT; if (size == 0) { needed_size = 0; for (u16 i = 0; i < inode->num_ads; i++) needed_size += inode->ads_entries[i].stream_name_utf8_len + 6; return needed_size; } else { char *p = list; for (u16 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; struct wimfs_context *ctx = wimfs_get_context(); parent = get_parent_dentry(ctx->wim, 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 = ctx->next_ino++; dentry_add_child(parent, newdir); return 0; } /* Creates a regular file. */ static int wimfs_mknod(const char *path, mode_t mode, dev_t rdev) { const char *stream_name; struct wimfs_context *ctx = wimfs_get_context(); if ((ctx->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 inode *inode; char *p = (char*)stream_name - 1; wimlib_assert(*p == ':'); *p = '\0'; inode = wim_pathname_to_inode(ctx->wim, path); if (!inode) return -ENOENT; if (!inode_is_regular_file(inode)) return -ENOENT; if (inode_get_ads_entry(inode, stream_name, NULL)) return -EEXIST; new_entry = inode_add_ads(inode, stream_name); if (!new_entry) return -ENOMEM; } 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(ctx->wim, 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 = ctx->next_ino++; dentry_add_child(parent, dentry); } 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; struct wimfs_context *ctx = wimfs_get_context(); ret = lookup_resource(ctx->wim, path, get_lookup_flags(ctx), &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, ctx); if (ret != 0) return ret; } ret = alloc_wimlib_fd(inode, stream_id, lte, &fd, wimfs_ctx_readonly(ctx)); 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; struct wimfs_context *ctx = wimfs_get_context(); WIMStruct *w = ctx->wim; 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, wimfs_ctx_readonly(ctx)); 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->f_lte) /* Empty stream with no lookup table entry */ return 0; if (fd->f_lte->resource_location == RESOURCE_IN_STAGING_FILE) { /* Read from staging file */ wimlib_assert(fd->f_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 */ wimlib_assert(fd->f_lte->resource_location == RESOURCE_IN_WIM); u64 res_size = wim_resource_size(fd->f_lte); if (offset > res_size) return -EOVERFLOW; size = min(size, res_size - offset); if (read_wim_resource(fd->f_lte, (u8*)buf, size, offset, WIMLIB_RESOURCE_FLAG_MULTITHREADED) != 0) return -EIO; return size; } } struct fill_params { void *buf; fuse_fill_dir_t filler; }; static int dentry_fuse_fill(struct dentry *dentry, void *arg) { struct fill_params *fill_params = arg; return fill_params->filler(fill_params->buf, dentry->file_name_utf8, NULL, 0); } /* 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; if (!fd) return -EBADF; inode = fd->f_inode; struct fill_params fill_params = { .buf = buf, .filler = filler, }; filler(buf, ".", NULL, 0); filler(buf, "..", NULL, 0); return for_dentry_in_rbtree(inode->children.rb_node, dentry_fuse_fill, &fill_params); } static int wimfs_readlink(const char *path, char *buf, size_t buf_len) { struct wimfs_context *ctx = wimfs_get_context(); struct inode *inode = wim_pathname_to_inode(ctx->wim, path); int ret; if (!inode) return -ENOENT; if (!inode_is_symlink(inode)) return -EINVAL; ret = inode_readlink(inode, buf, buf_len, ctx->wim, WIMLIB_RESOURCE_FLAG_MULTITHREADED); 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 inode *inode; struct ads_entry *ads_entry; u16 ads_idx; struct wimfs_context *ctx = wimfs_get_context(); if (!(ctx->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(ctx->wim, path); if (!inode) return -ENOENT; ads_entry = inode_get_ads_entry(inode, name, &ads_idx); if (!ads_entry) return -ENOATTR; inode_remove_ads(inode, ads_idx, ctx->wim->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; WIMStruct *w = wimfs_get_WIMStruct(); 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 (inode_has_children(dst->d_inode)) 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); dentry_add_child(parent_of_dst, src); return 0; } /* Remove a directory */ static int wimfs_rmdir(const char *path) { struct dentry *dentry; WIMStruct *w = wimfs_get_WIMStruct(); 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; struct wimfs_context *ctx = wimfs_get_context(); if (!(ctx->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(ctx->wim, 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, ctx->wim->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(ctx->wim->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(ctx->wim->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; struct wimfs_context *ctx = wimfs_get_context(); dentry_parent = get_parent_dentry(ctx->wim, 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 = ctx->next_ino++; inode->resolved = true; if (inode_set_symlink(inode, to, ctx->wim->lookup_table, NULL) != 0) goto out_free_dentry; dentry_add_child(dentry_parent, dentry); 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; struct wimfs_context *ctx = wimfs_get_context(); ret = lookup_resource(ctx->wim, path, get_lookup_flags(ctx), &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, ctx); } return ret; } /* Remove a regular file */ static int wimfs_unlink(const char *path) { struct dentry *dentry; struct lookup_table_entry *lte; int ret; u16 stream_idx; struct wimfs_context *ctx = wimfs_get_context(); ret = lookup_resource(ctx->wim, path, get_lookup_flags(ctx), &dentry, <e, &stream_idx); if (ret != 0) return ret; if (stream_idx == 0) remove_dentry(dentry, ctx->wim->lookup_table); else inode_remove_ads(dentry->d_inode, stream_idx - 1, ctx->wim->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; WIMStruct *w = wimfs_get_WIMStruct(); 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; WIMStruct *w = wimfs_get_WIMStruct(); 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->f_lte); wimlib_assert(fd->f_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, .chmod = wimfs_chmod, .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, #if FUSE_MAJOR_VERSION > 2 || (FUSE_MAJOR_VERSION == 2 && FUSE_MINOR_VERSION >= 8) .flag_nullpath_ok = 1, #endif #if FUSE_MAJOR_VERSION > 2 || (FUSE_MAJOR_VERSION == 2 && FUSE_MINOR_VERSION >= 9) .flag_nopath = 1, .flag_utime_omit_ok = 1, #endif }; /* Mounts an image from a WIM file. */ WIMLIBAPI int wimlib_mount_image(WIMStruct *wim, int image, const char *dir, int mount_flags, WIMStruct **additional_swms, unsigned num_additional_swms, const char *staging_dir) { int argc = 0; char *argv[16]; int ret; char *dir_copy; struct lookup_table *joined_tab, *wim_tab_save; struct image_metadata *imd; struct wimfs_context ctx; DEBUG("Mount: wim = %p, image = %d, dir = %s, flags = %d, ", wim, image, dir, mount_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 ((mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) && (wim->hdr.total_parts != 1)) { ERROR("Cannot mount a split WIM read-write"); return WIMLIB_ERR_SPLIT_UNSUPPORTED; } 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; } if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { ret = wim_run_full_verifications(wim); if (ret != 0) goto out; } ret = select_wim_image(wim, image); if (ret != 0) goto out; imd = &wim->image_metadata[image - 1]; DEBUG("Selected image %d", image); if (imd->root_dentry->refcnt != 1) { ERROR("Cannot mount image that was just exported with " "wimlib_export_image()"); ret = WIMLIB_ERR_INVALID_PARAM; goto out; } if (imd->modified) { ERROR("Cannot mount image that was added " "with wimlib_add_image()"); ret = WIMLIB_ERR_INVALID_PARAM; goto out; } if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { ret = lock_wim(wim->fp, wim->filename); if (ret != 0) goto out; } if (!(mount_flags & (WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_NONE | WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR | WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_WINDOWS))) mount_flags |= WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR; DEBUG("Initializing struct wimfs_context"); init_wimfs_context(&ctx); ctx.wim = wim; ctx.mount_flags = mount_flags; DEBUG("Unlinking message queues in case they already exist"); ret = set_message_queue_names(&ctx, dir); if (ret != 0) goto out; unlink_message_queues(&ctx); DEBUG("Preparing arguments to fuse_main()"); dir_copy = STRDUP(dir); if (!dir_copy) goto out_free_message_queue_names; argv[argc++] = "imagex"; argv[argc++] = dir_copy; /* disable multi-threaded operation for read-write mounts */ if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) argv[argc++] = "-s"; if (mount_flags & WIMLIB_MOUNT_FLAG_DEBUG) argv[argc++] = "-d"; /* * We provide the use_ino option because we are going to assign inode * numbers oursides. The inodes will be given 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 ((mount_flags & WIMLIB_MOUNT_FLAG_READWRITE)) { /* Read-write mount. Make the staging directory */ ret = make_staging_dir(&ctx, staging_dir); if (ret != 0) goto out_free_dir_copy; } 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 /* Mark dentry tree as modified if read-write mount. */ if (mount_flags & WIMLIB_MOUNT_FLAG_READWRITE) { imd->modified = 1; imd->has_been_mounted_rw = 1; } /* 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); ctx.next_ino = assign_inode_numbers(&imd->inode_list); DEBUG("(next_ino = %"PRIu64")", ctx.next_ino); DEBUG("Calling fuse_main()"); ret = fuse_main(argc, argv, &wimfs_operations, &ctx); DEBUG("Returned from fuse_main() (ret = %d)", ret); if (ret) ret = WIMLIB_ERR_FUSE; out_free_dir_copy: FREE(dir_copy); out_free_message_queue_names: free_message_queue_names(&ctx); 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_image(). */ WIMLIBAPI int wimlib_unmount_image(const char *dir, int unmount_flags, wimlib_progress_func_t progress_func) { pid_t pid; int status; int ret; char msg[2]; struct timeval now; struct timespec timeout; long msgsize; struct wimfs_context ctx; char *mailbox; init_wimfs_context(&ctx); /* Open message queues between the unmount process and the * filesystem daemon. */ ret = set_message_queue_names(&ctx, dir); if (ret != 0) goto out; ret = open_message_queues(&ctx, false); if (ret != 0) goto out_free_message_queue_names; /* Send a message to the filesystem daemon saying whether to commit or * not. */ msg[0] = (unmount_flags & WIMLIB_UNMOUNT_FLAG_COMMIT) ? 1 : 0; msg[1] = (unmount_flags & WIMLIB_UNMOUNT_FLAG_CHECK_INTEGRITY) ? 1 : 0; DEBUG("Sending message: %scommit, %scheck", (msg[0] ? "" : "don't "), (msg[1] ? "" : "don't ")); ret = mq_send(ctx.unmount_to_daemon_mq, msg, 2, 1); if (ret == -1) { ERROR_WITH_ERRNO("Failed to notify filesystem daemon whether " "we want to commit changes or not"); ret = WIMLIB_ERR_MQUEUE; goto out_close_message_queues; } /* 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()"); ret = WIMLIB_ERR_FORK; goto out_close_message_queues; } if (pid == 0) { /* Child */ execlp("fusermount", "fusermount", "-u", dir, NULL); ERROR_WITH_ERRNO("Failed to execute `fusermount'"); exit(WIMLIB_ERR_FUSERMOUNT); } /* Parent */ ret = wait(&status); if (ret == -1) { ERROR_WITH_ERRNO("Failed to wait for fusermount process to " "terminate"); ret = WIMLIB_ERR_FUSERMOUNT; goto out_close_message_queues; } 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()"); ret = WIMLIB_ERR_FORK; goto out_close_message_queues; } if (pid == 0) { /* Child */ execlp("umount", "umount", dir, NULL); ERROR_WITH_ERRNO("Failed to execute `umount'"); exit(WIMLIB_ERR_FUSERMOUNT); } /* Parent */ ret = wait(&status); if (ret == -1) { ERROR_WITH_ERRNO("Failed to wait for `umount' process to " "terminate"); ret = WIMLIB_ERR_FUSERMOUNT; goto out_close_message_queues; } if (status != 0) { ERROR("`umount' exited with failure status"); ret = WIMLIB_ERR_FUSERMOUNT; goto out_close_message_queues; } } wimlib_assert(status == 0); /* 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? * No, this wouldn't work because we know the directory but not the WIM * file... * */ gettimeofday(&now, NULL); timeout.tv_sec = now.tv_sec + 600; timeout.tv_nsec = now.tv_usec * 1000; ret = get_mailbox(ctx.daemon_to_unmount_mq, 2, &msgsize, &mailbox); if (ret != 0) goto out_close_message_queues; mailbox[0] = 0; DEBUG("Waiting for message telling us whether the unmount was " "successful or not."); ret = mq_timedreceive(ctx.daemon_to_unmount_mq, mailbox, msgsize, NULL, &timeout); if (ret == -1) { if (errno == ETIMEDOUT) { ERROR("Timed out- probably the filesystem daemon " "crashed and the WIM was not written " "successfully."); ret = WIMLIB_ERR_TIMEOUT; } else { ERROR_WITH_ERRNO("mq_receive()"); ret = WIMLIB_ERR_MQUEUE; } goto out_free_mailbox; } DEBUG("Received message: Unmount %s", (mailbox[0] ? "Failed" : "Ok")); ret = mailbox[0]; if (ret) ERROR("Unmount failed"); out_free_mailbox: FREE(mailbox); out_close_message_queues: close_message_queues(&ctx); out_free_message_queue_names: free_message_queue_names(&ctx); out: return ret; } #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_image(const char *dir, int unmount_flags, wimlib_progress_func_t progress_func) { return mount_unsupported_error(); } WIMLIBAPI int wimlib_mount_image(WIMStruct *wim_p, int image, const char *dir, int mount_flags, WIMStruct **additional_swms, unsigned num_additional_swms, const char *staging_dir) { return mount_unsupported_error(); } #endif /* WITH_FUSE */