X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fpath-util.c;h=53c007976078b90f9bec55e7c42ebf0deb73d107;hb=a7f7d1bde43fc825c49afea3f946f5b4b3d563e0;hp=8c43d060fb2ed93f1eb008f4c56cb63cfe3352a9;hpb=6feeeab0bc40b5a7f208adf79909fb85e2208e8e;p=elogind.git diff --git a/src/shared/path-util.c b/src/shared/path-util.c index 8c43d060f..53c007976 100644 --- a/src/shared/path-util.c +++ b/src/shared/path-util.c @@ -19,15 +19,12 @@ along with systemd; If not, see . ***/ -#include #include #include #include #include -#include #include #include -#include #include #include "macro.h" @@ -403,12 +400,18 @@ char* path_startswith(const char *path, const char *prefix) { } } -bool path_equal(const char *a, const char *b) { +int path_compare(const char *a, const char *b) { + int d; + assert(a); assert(b); - if ((a[0] == '/') != (b[0] == '/')) - return false; + /* A relative path and an abolute path must not compare as equal. + * Which one is sorted before the other does not really matter. + * Here a relative path is ordered before an absolute path. */ + d = (a[0] == '/') - (b[0] == '/'); + if (d) + return d; for (;;) { size_t j, k; @@ -417,25 +420,40 @@ bool path_equal(const char *a, const char *b) { b += strspn(b, "/"); if (*a == 0 && *b == 0) - return true; + return 0; - if (*a == 0 || *b == 0) - return false; + /* Order prefixes first: "/foo" before "/foo/bar" */ + if (*a == 0) + return -1; + if (*b == 0) + return 1; j = strcspn(a, "/"); k = strcspn(b, "/"); - if (j != k) - return false; + /* Alphabetical sort: "/foo/aaa" before "/foo/b" */ + d = memcmp(a, b, MIN(j, k)); + if (d) + return (d > 0) - (d < 0); /* sign of d */ - if (memcmp(a, b, j) != 0) - return false; + /* Sort "/foo/a" before "/foo/aaa" */ + d = (j > k) - (j < k); /* sign of (j - k) */ + if (d) + return d; a += j; b += k; } } +bool path_equal(const char *a, const char *b) { + return path_compare(a, b) == 0; +} + +bool path_equal_or_files_same(const char *a, const char *b) { + return path_equal(a, b) || files_same(a, b) > 0; +} + char* path_join(const char *root, const char *path, const char *rest) { assert(path); @@ -454,14 +472,11 @@ char* path_join(const char *root, const char *path, const char *rest) { int path_is_mount_point(const char *t, bool allow_symlink) { - union file_handle_union h = { - .handle.handle_bytes = MAX_HANDLE_SZ - }; - - int mount_id, mount_id_parent; - _cleanup_free_ char *parent = NULL; + union file_handle_union h = FILE_HANDLE_INIT; + int mount_id = -1, mount_id_parent = -1; struct stat a, b; int r; + _cleanup_close_ int fd = -1; bool nosupp = false; /* We are not actually interested in the file handles, but @@ -471,9 +486,21 @@ int path_is_mount_point(const char *t, bool allow_symlink) { if (path_equal(t, "/")) return 1; - r = name_to_handle_at(AT_FDCWD, t, &h.handle, &mount_id, allow_symlink ? AT_SYMLINK_FOLLOW : 0); + fd = openat(AT_FDCWD, t, O_RDONLY|O_NONBLOCK|O_DIRECTORY|O_CLOEXEC|(allow_symlink ? 0 : O_PATH)); + if (fd < 0) { + if (errno == ENOENT) + return 0; + + return -errno; + } + + r = name_to_handle_at(fd, "", &h.handle, &mount_id, AT_EMPTY_PATH); if (r < 0) { - if (IN_SET(errno, ENOSYS, EOPNOTSUPP)) + if (errno == ENOSYS) + /* This kernel does not support name_to_handle_at() + * fall back to the traditional stat() logic. */ + goto fallback; + else if (errno == EOPNOTSUPP) /* This kernel or file system does not support * name_to_handle_at(), hence fallback to the * traditional stat() logic */ @@ -484,12 +511,9 @@ int path_is_mount_point(const char *t, bool allow_symlink) { return -errno; } - r = path_get_parent(t, &parent); - if (r < 0) - return r; h.handle.handle_bytes = MAX_HANDLE_SZ; - r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, AT_SYMLINK_FOLLOW); + r = name_to_handle_at(fd, "..", &h.handle, &mount_id_parent, 0); if (r < 0) if (errno == EOPNOTSUPP) if (nosupp) @@ -508,10 +532,7 @@ int path_is_mount_point(const char *t, bool allow_symlink) { return mount_id != mount_id_parent; fallback: - if (allow_symlink) - r = stat(t, &a); - else - r = lstat(t, &a); + r = fstatat(fd, "", &a, AT_EMPTY_PATH); if (r < 0) { if (errno == ENOENT) @@ -520,11 +541,8 @@ fallback: return -errno; } - r = path_get_parent(t, &parent); - if (r < 0) - return r; - r = stat(parent, &b); + r = fstatat(fd, "..", &b, 0); if (r < 0) return -errno; @@ -556,14 +574,14 @@ int path_is_os_tree(const char *path) { int r; /* We use /usr/lib/os-release as flag file if something is an OS */ - p = strappenda(path, "/usr/lib/os-release"); + p = strjoina(path, "/usr/lib/os-release"); r = access(p, F_OK); if (r >= 0) return 1; /* Also check for the old location in /etc, just in case. */ - p = strappenda(path, "/etc/os-release"); + p = strjoina(path, "/etc/os-release"); r = access(p, F_OK); return r >= 0; @@ -661,7 +679,7 @@ int fsck_exists(const char *fstype) { const char *checker; int r; - checker = strappenda("fsck.", fstype); + checker = strjoina("fsck.", fstype); r = find_binary(checker, true, &p); if (r < 0)