From a4a2ec8c2a0db760914359bbbaa23fefcbc3c7fb Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Sat, 25 Aug 2012 00:13:31 -0500 Subject: [PATCH] Implement XATTR interface to ADS in wimfs --- src/dentry.c | 15 +++-- src/mount.c | 174 ++++++++++++++++++++++++++++++++++++++++++++----- src/resource.c | 7 +- 3 files changed, 169 insertions(+), 27 deletions(-) diff --git a/src/dentry.c b/src/dentry.c index d8b3e60e..c84a9565 100644 --- a/src/dentry.c +++ b/src/dentry.c @@ -99,13 +99,18 @@ void dentry_update_all_timestamps(struct dentry *dentry) struct ads_entry *dentry_get_ads_entry(struct dentry *dentry, const char *stream_name) { - size_t stream_name_len = strlen(stream_name); + size_t stream_name_len; if (!stream_name) return NULL; - for (u16 i = 0; i < dentry->num_ads; i++) - if (ads_entry_has_name(&dentry->ads_entries[i], - stream_name, stream_name_len)) - return &dentry->ads_entries[i]; + if (dentry->num_ads) { + u16 i = 0; + stream_name_len = strlen(stream_name); + do { + if (ads_entry_has_name(&dentry->ads_entries[i], + stream_name, stream_name_len)) + return &dentry->ads_entries[i]; + } while (++i != dentry->num_ads); + } return NULL; } diff --git a/src/mount.c b/src/mount.c index 03626cf4..ac4aeb37 100644 --- a/src/mount.c +++ b/src/mount.c @@ -44,6 +44,7 @@ #include #include #include +#include struct wimlib_fd { u16 idx; @@ -187,6 +188,20 @@ static void remove_dentry(struct dentry *dentry, put_dentry(dentry); } +static void remove_ads(struct dentry *dentry, + struct ads_entry *ads_entry, + struct lookup_table *lookup_table) +{ + struct lookup_table_entry *lte; + + wimlib_assert(dentry->resolved); + + lte = lte_decrement_refcnt(lte, lookup_table); + if (lte) + list_del(&ads_entry->lte_group_list.list); + dentry_remove_ads(dentry, ads_entry); +} + /* Transfers file attributes from a struct dentry to a `stat' buffer. */ int dentry_to_stbuf(const struct dentry *dentry, struct stat *stbuf) { @@ -490,6 +505,8 @@ static int extract_resource_to_staging_dir(struct dentry *dentry, new_lte->resource_entry.original_size = size; new_lte->refcnt = link_group_size; random_hash(new_lte->hash); + if (new_lte->staging_file_name) + FREE(new_lte->staging_file_name); new_lte->staging_file_name = staging_file_name; new_lte->resource_location = RESOURCE_IN_STAGING_FILE; @@ -977,11 +994,41 @@ static int wimfs_getattr(const char *path, struct stat *stbuf) return dentry_to_stbuf(dentry, stbuf); } +/* 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) { - /* XXX */ - return -ENOTSUP; + 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 (memcmp(name, "user.", 5) != 0) + return -ENOATTR; + name += 5; + + dentry = get_dentry(w, path); + if (!dentry) + return -ENOENT; + ads_entry = dentry_get_ads_entry(dentry, name); + 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, value); + if (ret != 0) + return -EIO; + return res_size; } /* Create a hard link */ @@ -1038,8 +1085,35 @@ static int wimfs_link(const char *to, const char *from) static int wimfs_listxattr(const char *path, char *list, size_t size) { - /* XXX */ - return -ENOTSUP; + struct dentry *dentry; + int ret; + char *p = list; + size_t needed_size; + unsigned i; + 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; + if (size == 0) { + needed_size = 0; + for (i = 0; i < dentry->num_ads; i++) + needed_size += dentry->ads_entries[i].stream_name_utf8_len + 6; + return needed_size; + } else { + for (i = 0; i < dentry->num_ads; i++) { + needed_size = dentry->ads_entries[i].stream_name_utf8_len + 6; + if (needed_size > size) + return -ERANGE; + p += sprintf(p, "user.%s", + dentry->ads_entries[i].stream_name_utf8) + 1; + size -= needed_size; + } + return p - list; + } } /* @@ -1171,7 +1245,8 @@ static int wimfs_open(const char *path, struct fuse_file_info *fi) * 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->staging_file_name) { + if (flags_writable(fi->flags) && + lte->resource_location != RESOURCE_IN_STAGING_FILE) { ret = extract_resource_to_staging_dir(dentry, stream_idx, <e, lte->resource_entry.original_size); if (ret != 0) @@ -1328,10 +1403,28 @@ static int wimfs_releasedir(const char *path, struct fuse_file_info *fi) return 0; } +/* Remove an alternate data stream through the XATTR interface */ static int wimfs_removexattr(const char *path, const char *name) { - /* XXX */ - return -ENOTSUP; + struct dentry *dentry; + struct ads_entry *ads_entry; + int ret; + if (!(mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) + return -ENOTSUP; + + if (memcmp(name, "user.", 5) != 0) + return -ENOATTR; + name += 5; + + dentry = get_dentry(w, path); + if (!dentry) + return -ENOENT; + + ads_entry = dentry_get_ads_entry(dentry, name); + if (!ads_entry) + return -ENOATTR; + remove_ads(dentry, ads_entry, w->lookup_table); + return 0; } /* Renames a file or directory. See rename (3) */ @@ -1420,11 +1513,65 @@ static int wimfs_rmdir(const char *path) return 0; } +/* 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) { - /* XXX */ - return -ENOTSUP; + struct dentry *dentry; + struct ads_entry *existing_ads_entry; + struct ads_entry *new_ads_entry; + struct lookup_table_entry *existing_lte; + struct lookup_table_entry *lte; + u8 value_hash[SHA1_HASH_SIZE]; + int ret; + int fd; + + if (!(mount_flags & WIMLIB_MOUNT_FLAG_STREAM_INTERFACE_XATTR)) + return -ENOTSUP; + + dentry = get_dentry(w, path); + if (!dentry) + return -ENOENT; + existing_ads_entry = dentry_get_ads_entry(dentry, name); + if (existing_ads_entry) { + if (flags & XATTR_CREATE) + return -EEXIST; + remove_ads(dentry, existing_ads_entry, w->lookup_table); + } else { + if (flags & XATTR_REPLACE) + return -ENOATTR; + } + new_ads_entry = dentry_add_ads(dentry, name); + if (!new_ads_entry) + return -ENOMEM; + + sha1_buffer(value, size, value_hash); + + existing_lte = __lookup_resource(w->lookup_table, value_hash); + + if (existing_lte) { + lte = existing_lte; + lte->refcnt++; + } else { + char *value_copy; + lte = new_lookup_table_entry(); + if (!lte) + return -ENOMEM; + value_copy = MALLOC(size); + if (!value_copy) { + FREE(lte); + return -ENOMEM; + } + 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; } static int wimfs_symlink(const char *to, const char *from) @@ -1522,13 +1669,8 @@ static int wimfs_unlink(const char *path) remove_dentry(dentry, w->lookup_table); } else { /* We are removing an alternate data stream. */ - struct ads_entry *ads_entry; - - ads_entry = &dentry->ads_entries[stream_idx - 1]; - lte = lte_decrement_refcnt(lte, w->lookup_table); - if (lte) - list_del(&ads_entry->lte_group_list.list); - dentry_remove_ads(dentry, ads_entry); + remove_ads(dentry, &dentry->ads_entries[stream_idx - 1], + w->lookup_table); } /* Beware: The lookup table entry(s) may still be referenced by users * that have opened the corresponding streams. They are freed later in diff --git a/src/resource.c b/src/resource.c index b1bc947d..d81421c5 100644 --- a/src/resource.c +++ b/src/resource.c @@ -447,16 +447,11 @@ int read_wim_resource(const struct lookup_table_entry *lte, u8 buf[], ctype, size, offset, buf); break; case RESOURCE_IN_STAGING_FILE: - /* The WIM FUSE implementation needs to handle multiple open - * file descriptors per lookup table entry so it does not - * currently work with this function. */ - wimlib_assert(lte->staging_file_name); - wimlib_assert(0); - break; case RESOURCE_IN_FILE_ON_DISK: /* The resource is in some file on the external filesystem and * needs to be read uncompressed */ wimlib_assert(lte->file_on_disk); + wimlib_assert(<e->file_on_disk == <e->staging_file_name); /* Use existing file pointer if available; otherwise open one * temporarily */ if (lte->file_on_disk_fp) { -- 2.43.0