Merge pull request #27885 from DaanDeMeyer/please-dont-make-me-write-more-openat-helpers

Add more openat like helper functions

src/basic/chase.c

@@ -81,7 +81,6 @@ int chaseat(int dir_fd, const char *path, ChaseFlags flags, char **ret_path, int
         const char *todo;
         int r;
 
-        assert(path);
         assert(!FLAGS_SET(flags, CHASE_PREFIX_ROOT));
         assert(!FLAGS_SET(flags, CHASE_STEP|CHASE_EXTRACT_FILENAME));
         assert(!FLAGS_SET(flags, CHASE_TRAIL_SLASH|CHASE_EXTRACT_FILENAME));

src/basic/chattr-util.c

@@ -9,29 +9,29 @@
 #include "chattr-util.h"
 #include "errno-util.h"
 #include "fd-util.h"
+#include "fs-util.h"
 #include "macro.h"
 #include "string-util.h"
 
-int chattr_full(const char *path,
-                int fd,
-                unsigned value,
-                unsigned mask,
-                unsigned *ret_previous,
-                unsigned *ret_final,
-                ChattrApplyFlags flags) {
+int chattr_full(
+              int dir_fd,
+              const char *path,
+              unsigned value,
+              unsigned mask,
+              unsigned *ret_previous,
+              unsigned *ret_final,
+              ChattrApplyFlags flags) {
 
-        _cleanup_close_ int fd_will_close = -EBADF;
+        _cleanup_close_ int fd = -EBADF;
         unsigned old_attr, new_attr;
         int set_flags_errno = 0;
         struct stat st;
 
-        assert(path || fd >= 0);
+        assert(dir_fd >= 0 || dir_fd == AT_FDCWD);
 
-        if (fd < 0) {
-                fd = fd_will_close = open(path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW);
-                if (fd < 0)
-                        return -errno;
-        }
+        fd = xopenat(dir_fd, path, O_RDONLY|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, /* xopen_flags = */ 0, /* mode = */ 0);
+        if (fd < 0)
+                return -errno;
 
         if (fstat(fd, &st) < 0)
                 return -errno;

src/basic/chattr-util.h

@@ -1,6 +1,7 @@
 /* SPDX-License-Identifier: LGPL-2.1-or-later */
 #pragma once
 
+#include <fcntl.h>
 #include <linux/fs.h>
 #include <stdbool.h>
 #include <stddef.h>
@@ -39,13 +40,15 @@ typedef enum ChattrApplyFlags {
         CHATTR_WARN_UNSUPPORTED_FLAGS = 1 << 1,
 } ChattrApplyFlags;
 
-int chattr_full(const char *path, int fd, unsigned value, unsigned mask, unsigned *ret_previous, unsigned *ret_final, ChattrApplyFlags flags);
-
+int chattr_full(int dir_fd, const char *path, unsigned value, unsigned mask, unsigned *ret_previous, unsigned *ret_final, ChattrApplyFlags flags);
+static inline int chattr_at(int dir_fd, const char *path, unsigned value, unsigned mask, unsigned *previous) {
+        return chattr_full(dir_fd, path, value, mask, previous, NULL, 0);
+}
 static inline int chattr_fd(int fd, unsigned value, unsigned mask, unsigned *previous) {
-        return chattr_full(NULL, fd, value, mask, previous, NULL, 0);
+        return chattr_full(fd, NULL, value, mask, previous, NULL, 0);
 }
 static inline int chattr_path(const char *path, unsigned value, unsigned mask, unsigned *previous) {
-        return chattr_full(path, -1, value, mask, previous, NULL, 0);
+        return chattr_full(AT_FDCWD, path, value, mask, previous, NULL, 0);
 }
 
 int read_attr_fd(int fd, unsigned *ret);
@@ -57,5 +60,5 @@ int read_attr_path(const char *p, unsigned *ret);
 #define CHATTR_SECRET_FLAGS (FS_SECRM_FL|FS_NODUMP_FL|FS_SYNC_FL|FS_NOCOW_FL)
 
 static inline int chattr_secret(int fd, ChattrApplyFlags flags) {
-        return chattr_full(NULL, fd, CHATTR_SECRET_FLAGS, CHATTR_SECRET_FLAGS, NULL, NULL, flags|CHATTR_FALLBACK_BITWISE);
+        return chattr_full(fd, NULL, CHATTR_SECRET_FLAGS, CHATTR_SECRET_FLAGS, NULL, NULL, flags|CHATTR_FALLBACK_BITWISE);
 }

src/basic/fd-util.c

@@ -891,12 +891,21 @@ int fd_get_diskseq(int fd, uint64_t *ret) {
         return 0;
 }
 
-int dir_fd_is_root(int dir_fd) {
+int path_is_root_at(int dir_fd, const char *path) {
         STRUCT_NEW_STATX_DEFINE(st);
         STRUCT_NEW_STATX_DEFINE(pst);
+        _cleanup_close_ int fd = -EBADF;
         int r;
 
-        assert(dir_fd >= 0);
+        assert(dir_fd >= 0 || dir_fd == AT_FDCWD);
+
+        if (!isempty(path)) {
+                fd = openat(dir_fd, path, O_PATH|O_CLOEXEC);
+                if (fd < 0)
+                        return -errno;
+
+                dir_fd = fd;
+        }
 
         r = statx_fallback(dir_fd, ".", 0, STATX_TYPE|STATX_INO|STATX_MNT_ID, &st.sx);
         if (r == -ENOTDIR)

src/basic/fd-util.h

@@ -101,9 +101,12 @@ int fd_is_opath(int fd);
 int read_nr_open(void);
 int fd_get_diskseq(int fd, uint64_t *ret);
 
-int dir_fd_is_root(int dir_fd);
+int path_is_root_at(int dir_fd, const char *path);
+static inline int dir_fd_is_root(int dir_fd) {
+        return path_is_root_at(dir_fd, NULL);
+}
 static inline int dir_fd_is_root_or_cwd(int dir_fd) {
-        return dir_fd == AT_FDCWD ? true : dir_fd_is_root(dir_fd);
+        return dir_fd == AT_FDCWD ? true : path_is_root_at(dir_fd, NULL);
 }
 
 /* The maximum length a buffer for a /proc/self/fd/<fd> path needs */

src/basic/fs-util.c

@@ -1097,7 +1097,6 @@ int xopenat(int dir_fd, const char *path, int open_flags, XOpenFlags xopen_flags
         int r;
 
         assert(dir_fd >= 0 || dir_fd == AT_FDCWD);
-        assert(path);
 
         if (isempty(path)) {
                 assert(!FLAGS_SET(open_flags, O_CREAT|O_EXCL));

src/basic/stat-util.c

@@ -207,20 +207,13 @@ bool is_fs_type(const struct statfs *s, statfs_f_type_t magic_value) {
         return F_TYPE_EQUAL(s->f_type, magic_value);
 }
 
-int fd_is_fs_type(int fd, statfs_f_type_t magic_value) {
+int is_fs_type_at(int dir_fd, const char *path, statfs_f_type_t magic_value) {
         struct statfs s;
+        int r;
 
-        if (fstatfs(fd, &s) < 0)
-                return -errno;
-
-        return is_fs_type(&s, magic_value);
-}
-
-int path_is_fs_type(const char *path, statfs_f_type_t magic_value) {
-        struct statfs s;
-
-        if (statfs(path, &s) < 0)
-                return -errno;
+        r = xstatfsat(dir_fd, path, &s);
+        if (r < 0)
+                return r;
 
         return is_fs_type(&s, magic_value);
 }
@@ -461,7 +454,6 @@ int xstatfsat(int dir_fd, const char *path, struct statfs *ret) {
         _cleanup_close_ int fd = -EBADF;
 
         assert(dir_fd >= 0 || dir_fd == AT_FDCWD);
-        assert(path);
         assert(ret);
 
         fd = xopenat(dir_fd, path, O_PATH|O_CLOEXEC|O_NOCTTY, /* xopen_flags = */ 0, /* mode = */ 0);

src/basic/stat-util.h

@@ -48,8 +48,13 @@ static inline int inode_same(const char *filea, const char *fileb, int flags) {
 typedef typeof(((struct statfs*)NULL)->f_type) statfs_f_type_t;
 
 bool is_fs_type(const struct statfs *s, statfs_f_type_t magic_value) _pure_;
-int fd_is_fs_type(int fd, statfs_f_type_t magic_value);
-int path_is_fs_type(const char *path, statfs_f_type_t magic_value);
+int is_fs_type_at(int dir_fd, const char *path, statfs_f_type_t magic_value);
+static inline int fd_is_fs_type(int fd, statfs_f_type_t magic_value) {
+        return is_fs_type_at(fd, NULL, magic_value);
+}
+static inline int path_is_fs_type(const char *path, statfs_f_type_t magic_value) {
+        return is_fs_type_at(AT_FDCWD, path, magic_value);
+}
 
 bool is_temporary_fs(const struct statfs *s) _pure_;
 bool is_network_fs(const struct statfs *s) _pure_;