From 24d97575393f0afb01f5475c8cc5678e0df713bc Mon Sep 17 00:00:00 2001 From: Bill Kendall Date: Thu, 22 Oct 2009 16:52:23 +0000 Subject: [PATCH] add lpath_to_handle to libhandle path_to_handle() is not reliable when called on a path which is a symlink. If the symlink is dangling, or if its points to a non-XFS filesystem then path_to_handle() will fail. The reason is that path_to_handle() must open the path in order to obtain an fd for the xfsctl call. It's common during xfsrestore to have dangling symlinks since the target of the link may not be restored before the symlink. This patch adds a new function to libhandle, lpath_to_handle. It is just like path_to_handle, except it takes a filesystem path in addition to the path which you want convert to a handle. Alex Elder is going to take care of bumping the libhandle minor number, and adjusting the xfsdump/xfsprogs version numbers and dependencies to ensure a compatible libhandle is installed for xfsdump. Signed-off-by: Bill Kendall Reviewed-by: Alex Elder Signed-off-by: Alex Elder --- include/handle.h | 2 ++ libhandle/handle.c | 17 +++++++++++++++-- 2 files changed, 17 insertions(+), 2 deletions(-) diff --git a/include/handle.h b/include/handle.h index b211a2f45..3f1a137f7 100644 --- a/include/handle.h +++ b/include/handle.h @@ -27,6 +27,8 @@ struct attrlist_cursor; struct parent; extern int path_to_handle (char *__path, void **__hanp, size_t *__hlen); +extern int lpath_to_handle (char *__fspath, char *__path, + void **__hanp, size_t *__hlen); extern int path_to_fshandle (char *__path, void **__fshanp, size_t *__fshlen); extern int handle_to_fshandle (void *__hanp, size_t __hlen, void **__fshanp, size_t *__fshlen); diff --git a/libhandle/handle.c b/libhandle/handle.c index 627679748..6c9380de3 100644 --- a/libhandle/handle.c +++ b/libhandle/handle.c @@ -110,17 +110,30 @@ path_to_handle( char *path, /* input, path to convert */ void **hanp, /* output, pointer to data */ size_t *hlen) /* output, size of returned data */ +{ + return lpath_to_handle(path, path, hanp, hlen); +} + +/* Like path_to_handle, but reliable for paths which are either dangling + * symlinks or symlinks whose targets are not in XFS filesystems. + */ +int +lpath_to_handle( + char *fspath, /* input, path in filesystem */ + char *path, /* input, path to convert */ + void **hanp, /* output, pointer to data */ + size_t *hlen) /* output, size of returned data */ { int fd; int result; comarg_t obj; - fd = open(path, O_RDONLY); + fd = open(fspath, O_RDONLY); if (fd < 0) return -1; obj.path = path; - result = obj_to_handle(path, fd, XFS_IOC_PATH_TO_HANDLE, + result = obj_to_handle(fspath, fd, XFS_IOC_PATH_TO_HANDLE, obj, hanp, hlen); close(fd); return result; -- 2.39.5