X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=src%2Fshared%2Fpath-util.c;h=00d2d44993d3711adfc2b244e994360d1f2a8912;hp=efe464d7040d25bd526ae9181132e48ca7e62bf6;hb=2695c5c44e028d1bc07404baf3357e5a6017fc57;hpb=5ae4d543cb9b45ad6c6b82b78da1d6abc2291cdb diff --git a/src/shared/path-util.c b/src/shared/path-util.c index efe464d70..00d2d4499 100644 --- a/src/shared/path-util.c +++ b/src/shared/path-util.c @@ -129,7 +129,7 @@ char *path_make_absolute_cwd(const char *p) { if (!cwd) return NULL; - return path_make_absolute(p, cwd); + return strjoin(cwd, "/", p, NULL); } int path_make_relative(const char *from_dir, const char *to_path, char **_r) { @@ -238,7 +238,7 @@ char **path_strv_make_absolute_cwd(char **l) { return l; } -char **path_strv_canonicalize_absolute(char **l, const char *prefix) { +char **path_strv_resolve(char **l, const char *prefix) { char **s; unsigned k = 0; bool enomem = false; @@ -306,6 +306,7 @@ char **path_strv_canonicalize_absolute(char **l, const char *prefix) { } else { /* canonicalized path goes outside of * prefix, keep the original path instead */ + free(u); u = orig; orig = NULL; } @@ -323,12 +324,12 @@ char **path_strv_canonicalize_absolute(char **l, const char *prefix) { return l; } -char **path_strv_canonicalize_absolute_uniq(char **l, const char *prefix) { +char **path_strv_resolve_uniq(char **l, const char *prefix) { if (strv_isempty(l)) return l; - if (!path_strv_canonicalize_absolute(l, prefix)) + if (!path_strv_resolve(l, prefix)) return NULL; return strv_uniq(l); @@ -435,16 +436,30 @@ bool path_equal(const char *a, const char *b) { } } -int path_is_mount_point(const char *t, bool allow_symlink) { +char* path_join(const char *root, const char *path, const char *rest) { + assert(path); + + if (!isempty(root)) + return strjoin(root, endswith(root, "/") ? "" : "/", + path[0] == '/' ? path+1 : path, + rest ? (endswith(path, "/") ? "" : "/") : NULL, + rest && rest[0] == '/' ? rest+1 : rest, + NULL); + else + return strjoin(path, + rest ? (endswith(path, "/") ? "" : "/") : NULL, + rest && rest[0] == '/' ? rest+1 : rest, + NULL); +} - union file_handle_union h = { - .handle.handle_bytes = MAX_HANDLE_SZ - }; +int path_is_mount_point(const char *t, bool allow_symlink) { - int mount_id, mount_id_parent; - char *parent; + union file_handle_union h = FILE_HANDLE_INIT; + int mount_id = -1, mount_id_parent = -1; + _cleanup_free_ char *parent = NULL; struct stat a, b; int r; + bool nosupp = false; /* We are not actually interested in the file handles, but * name_to_handle_at() also passes us the mount ID, hence use @@ -455,16 +470,19 @@ int path_is_mount_point(const char *t, bool allow_symlink) { r = name_to_handle_at(AT_FDCWD, t, &h.handle, &mount_id, allow_symlink ? AT_SYMLINK_FOLLOW : 0); 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 */ - goto fallback; - - if (errno == ENOENT) + nosupp = true; + else if (errno == ENOENT) return 0; - - return -errno; + else + return -errno; } r = path_get_parent(t, &parent); @@ -472,19 +490,23 @@ int path_is_mount_point(const char *t, bool allow_symlink) { return r; h.handle.handle_bytes = MAX_HANDLE_SZ; - r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, 0); - free(parent); - if (r < 0) { - /* The parent can't do name_to_handle_at() but the - * directory we are interested in can? If so, it must - * be a mount point */ + r = name_to_handle_at(AT_FDCWD, parent, &h.handle, &mount_id_parent, AT_SYMLINK_FOLLOW); + if (r < 0) if (errno == EOPNOTSUPP) - return 1; - - return -errno; - } - - return mount_id != mount_id_parent; + if (nosupp) + /* Neither parent nor child do name_to_handle_at()? + We have no choice but to fall back. */ + goto fallback; + else + /* The parent can't do name_to_handle_at() but + * the directory we are interested in can? + * Or the other way around? + * If so, it must be a mount point. */ + return 1; + else + return -errno; + else + return mount_id != mount_id_parent; fallback: if (allow_symlink) @@ -499,12 +521,14 @@ fallback: return -errno; } + free(parent); + parent = NULL; + r = path_get_parent(t, &parent); if (r < 0) return r; - r = lstat(parent, &b); - free(parent); + r = stat(parent, &b); if (r < 0) return -errno; @@ -519,7 +543,16 @@ int path_is_read_only_fs(const char *path) { if (statvfs(path, &st) < 0) return -errno; - return !!(st.f_flag & ST_RDONLY); + if (st.f_flag & ST_RDONLY) + return true; + + /* On NFS, statvfs() might not reflect whether we can actually + * write to the remote share. Let's try again with + * access(W_OK) which is more reliable, at least sometimes. */ + if (access(path, W_OK) < 0 && errno == EROFS) + return true; + + return false; } int path_is_os_tree(const char *path) { @@ -540,11 +573,11 @@ int path_is_os_tree(const char *path) { return r >= 0; } -int find_binary(const char *name, char **filename) { +int find_binary(const char *name, bool local, char **filename) { assert(name); - if (strchr(name, '/')) { - if (access(name, X_OK) < 0) + if (is_path(name)) { + if (local && access(name, X_OK) < 0) return -errno; if (filename) { @@ -560,7 +593,7 @@ int find_binary(const char *name, char **filename) { return 0; } else { const char *path; - char *state, *w; + const char *word, *state; size_t l; /** @@ -571,10 +604,10 @@ int find_binary(const char *name, char **filename) { if (!path) path = DEFAULT_PATH; - FOREACH_WORD_SEPARATOR(w, l, path, ":", state) { + FOREACH_WORD_SEPARATOR(word, l, path, ":", state) { _cleanup_free_ char *p = NULL; - if (asprintf(&p, "%.*s/%s", (int) l, w, name) < 0) + if (asprintf(&p, "%.*s/%s", (int) l, word, name) < 0) return -ENOMEM; if (access(p, X_OK) < 0) @@ -628,8 +661,25 @@ bool paths_check_timestamp(const char* const* paths, usec_t *timestamp, bool upd } int fsck_exists(const char *fstype) { + _cleanup_free_ char *p = NULL, *d = NULL; const char *checker; + int r; checker = strappenda("fsck.", fstype); - return find_binary(checker, NULL); + + r = find_binary(checker, true, &p); + if (r < 0) + return r; + + /* An fsck that is linked to /bin/true is a non-existent + * fsck */ + + r = readlink_malloc(p, &d); + if (r >= 0 && + (path_equal(d, "/bin/true") || + path_equal(d, "/usr/bin/true") || + path_equal(d, "/dev/null"))) + return -ENOENT; + + return 0; }