Add erofs_read_xattrs_from_disk() helper to read extended attributes from disk.
Signed-off-by: Jingbo Xu <[email protected]> --- include/erofs/xattr.h | 1 + lib/xattr.c | 76 +++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 77 insertions(+) diff --git a/include/erofs/xattr.h b/include/erofs/xattr.h index dc27cf6..634daf9 100644 --- a/include/erofs/xattr.h +++ b/include/erofs/xattr.h @@ -85,6 +85,7 @@ int erofs_xattr_write_name_prefixes(struct erofs_sb_info *sbi, FILE *f); int erofs_setxattr(struct erofs_inode *inode, char *key, const void *value, size_t size); +int erofs_read_xattrs_from_disk(struct erofs_inode *inode); #ifdef __cplusplus } diff --git a/lib/xattr.c b/lib/xattr.c index 12f580e..8d8f9f0 100644 --- a/lib/xattr.c +++ b/lib/xattr.c @@ -493,6 +493,82 @@ int erofs_scan_file_xattrs(struct erofs_inode *inode) return erofs_droid_xattr_set_caps(inode); } +static struct xattr_item *erofs_read_xattr_from_disk(struct erofs_inode *inode, + char *key) +{ + ssize_t ret; + u8 prefix; + u16 prefixlen; + unsigned int len[2]; + char *kvbuf; + + if (!match_prefix(key, &prefix, &prefixlen)) + return ERR_PTR(-ENODATA); + + ret = erofs_getxattr(inode, key, NULL, 0); + if (ret < 0) + return ERR_PTR(-errno); + + /* allocate key-value buffer */ + len[0] = strlen(key) - prefixlen; + len[1] = ret; + kvbuf = malloc(len[0] + len[1]); + if (!kvbuf) + return ERR_PTR(-ENOMEM); + memcpy(kvbuf, key + prefixlen, len[0]); + if (len[1]) { + ret = erofs_getxattr(inode, key, kvbuf + len[0], len[1]); + if (ret < 0) { + free(kvbuf); + return ERR_PTR(-errno); + } + if (ret != len[1]) { + erofs_err("size of xattr value got changed just now (%u-> %ld)", + len[1], (long)ret); + len[1] = ret; + } + } + return get_xattritem(prefix, kvbuf, len); +} + +int erofs_read_xattrs_from_disk(struct erofs_inode *inode) +{ + ssize_t kllen; + char *keylst, *key; + struct xattr_item *item; + int ret; + + init_list_head(&inode->i_xattrs); + kllen = erofs_listxattr(inode, NULL, 0); + if (kllen < 0) + return kllen; + if (kllen <= 1) + return 0; + + keylst = malloc(kllen); + if (!keylst) + return -ENOMEM; + + ret = erofs_listxattr(inode, keylst, kllen); + if (ret < 0) + goto err; + + for (key = keylst; key < keylst + kllen; key += strlen(key) + 1) { + item = erofs_read_xattr_from_disk(inode, key); + if (IS_ERR(item)) { + ret = PTR_ERR(item); + goto err; + } + + ret = erofs_xattr_add(&inode->i_xattrs, item); + if (ret < 0) + goto err; + } +err: + free(keylst); + return ret; +} + int erofs_prepare_xattr_ibody(struct erofs_inode *inode) { int ret; -- 2.19.1.6.gb485710b
