1 files changed, 110 insertions, 0 deletions
diff --git a/src/basic/fd-util.h b/src/basic/fd-util.h
new file mode 100644
index 0000000..4085a24
--- /dev/null
+++ b/src/basic/fd-util.h
@@ -0,0 +1,110 @@
+/* SPDX-License-Identifier: LGPL-2.1+ */
+#pragma once
+
+#include <dirent.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <sys/socket.h>
+
+#include "macro.h"
+
+/* Make sure we can distinguish fd 0 and NULL */
+#define FD_TO_PTR(fd) INT_TO_PTR((fd)+1)
+#define PTR_TO_FD(p) (PTR_TO_INT(p)-1)
+
+int close_nointr(int fd);
+int safe_close(int fd);
+void safe_close_pair(int p[static 2]);
+
+static inline int safe_close_above_stdio(int fd) {
+        if (fd < 3) /* Don't close stdin/stdout/stderr, but still invalidate the fd by returning -1 */
+                return -1;
+
+        return safe_close(fd);
+}
+
+void close_many(const int fds[], size_t n_fd);
+
+int fclose_nointr(FILE *f);
+FILE* safe_fclose(FILE *f);
+DIR* safe_closedir(DIR *f);
+
+static inline void closep(int *fd) {
+        safe_close(*fd);
+}
+
+static inline void close_pairp(int (*p)[2]) {
+        safe_close_pair(*p);
+}
+
+static inline void fclosep(FILE **f) {
+        safe_fclose(*f);
+}
+
+DEFINE_TRIVIAL_CLEANUP_FUNC(FILE*, pclose);
+DEFINE_TRIVIAL_CLEANUP_FUNC(DIR*, closedir);
+
+#define _cleanup_close_ _cleanup_(closep)
+#define _cleanup_fclose_ _cleanup_(fclosep)
+#define _cleanup_pclose_ _cleanup_(pclosep)
+#define _cleanup_closedir_ _cleanup_(closedirp)
+#define _cleanup_close_pair_ _cleanup_(close_pairp)
+
+int fd_nonblock(int fd, bool nonblock);
+int fd_cloexec(int fd, bool cloexec);
+
+int close_all_fds(const int except[], size_t n_except);
+
+int same_fd(int a, int b);
+
+void cmsg_close_all(struct msghdr *mh);
+
+bool fdname_is_valid(const char *s);
+
+int fd_get_path(int fd, char **ret);
+
+int move_fd(int from, int to, int cloexec);
+
+enum {
+        ACQUIRE_NO_DEV_NULL = 1 << 0,
+        ACQUIRE_NO_MEMFD    = 1 << 1,
+        ACQUIRE_NO_PIPE     = 1 << 2,
+        ACQUIRE_NO_TMPFILE  = 1 << 3,
+        ACQUIRE_NO_REGULAR  = 1 << 4,
+};
+
+int acquire_data_fd(const void *data, size_t size, unsigned flags);
+
+int fd_duplicate_data_fd(int fd);
+
+/* Hint: ENETUNREACH happens if we try to connect to "non-existing" special IP addresses, such as ::5 */
+/* The kernel sends e.g., EHOSTUNREACH or ENONET to userspace in some ICMP error cases.
+ * See the icmp_err_convert[] in net/ipv4/icmp.c in the kernel sources */
+#define ERRNO_IS_DISCONNECT(r)                                          \
+        IN_SET(r,                                                       \
+               ENOTCONN, ECONNRESET, ECONNREFUSED, ECONNABORTED, EPIPE, \
+               ENETUNREACH, EHOSTUNREACH, ENOPROTOOPT, EHOSTDOWN, ENONET)
+
+/* Resource exhaustion, could be our fault or general system trouble */
+#define ERRNO_IS_RESOURCE(r) \
+        IN_SET(r, ENOMEM, EMFILE, ENFILE)
+
+int fd_move_above_stdio(int fd);
+
+int rearrange_stdio(int original_input_fd, int original_output_fd, int original_error_fd);
+
+static inline int make_null_stdio(void) {
+        return rearrange_stdio(-1, -1, -1);
+}
+
+/* Like TAKE_PTR() but for file descriptors, resetting them to -1 */
+#define TAKE_FD(fd)                             \
+        ({                                      \
+                int _fd_ = (fd);                \
+                (fd) = -1;                      \
+                _fd_;                           \
+        })
+
+int fd_reopen(int fd, int flags);
+
+int read_nr_open(void);