X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fshared%2Fpath-util.c;h=53c007976078b90f9bec55e7c42ebf0deb73d107;hb=92947a0878c5d129adb37ddbfdef35274ef5c6ae;hp=5863429c311d483f81a88a8076bbb295ae25e8e9;hpb=5216f599ff677a18016bfa1995d1f1e6a50e4a0b;p=elogind.git
diff --git a/src/shared/path-util.c b/src/shared/path-util.c
index 5863429c3..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"
@@ -129,7 +126,7 @@ 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 +235,7 @@ 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 +303,7 @@ 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 +321,12 @@ 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);
@@ -402,12 +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;
@@ -416,35 +420,64 @@ 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;
}
}
-int path_is_mount_point(const char *t, bool allow_symlink) {
+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);
+
+ 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;
struct stat a, b;
int r;
+ _cleanup_close_ int fd = -1;
+ 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
@@ -453,44 +486,53 @@ 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 */
- goto fallback;
-
- if (errno == ENOENT)
+ nosupp = true;
+ else if (errno == ENOENT)
return 0;
-
- return -errno;
+ else
+ 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, 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(fd, "..", &h.handle, &mount_id_parent, 0);
+ 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)
- r = stat(t, &a);
- else
- r = lstat(t, &a);
+ r = fstatat(fd, "", &a, AT_EMPTY_PATH);
if (r < 0) {
if (errno == ENOENT)
@@ -499,12 +541,8 @@ fallback:
return -errno;
}
- r = path_get_parent(t, &parent);
- if (r < 0)
- return r;
- r = lstat(parent, &b);
- free(parent);
+ r = fstatat(fd, "..", &b, 0);
if (r < 0)
return -errno;
@@ -519,26 +557,41 @@ 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) {
char *p;
int r;
- /* We use /etc/os-release as flag file if something is an OS */
+ /* We use /usr/lib/os-release as flag file if something is an OS */
+ p = strjoina(path, "/usr/lib/os-release");
+ r = access(p, F_OK);
+
+ if (r >= 0)
+ return 1;
- p = strappenda(path, "/etc/os-release");
+ /* Also check for the old location in /etc, just in case. */
+ p = strjoina(path, "/etc/os-release");
r = access(p, F_OK);
- return r < 0 ? 0 : 1;
+ 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) {
@@ -554,7 +607,7 @@ int find_binary(const char *name, char **filename) {
return 0;
} else {
const char *path;
- char *state, *w;
+ const char *word, *state;
size_t l;
/**
@@ -565,10 +618,10 @@ 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)
@@ -622,8 +675,25 @@ 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 = strjoina("fsck.", fstype);
- 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;
}