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-rw-r--r--src/shared/fdset.c323
1 files changed, 323 insertions, 0 deletions
diff --git a/src/shared/fdset.c b/src/shared/fdset.c
new file mode 100644
index 0000000..e5b8e92
--- /dev/null
+++ b/src/shared/fdset.c
@@ -0,0 +1,323 @@
+/* SPDX-License-Identifier: LGPL-2.1-or-later */
+
+#include <errno.h>
+#include <fcntl.h>
+#include <stddef.h>
+
+#include "sd-daemon.h"
+
+#include "alloc-util.h"
+#include "dirent-util.h"
+#include "fd-util.h"
+#include "fdset.h"
+#include "log.h"
+#include "macro.h"
+#include "parse-util.h"
+#include "path-util.h"
+#include "set.h"
+#include "stat-util.h"
+
+#define MAKE_SET(s) ((Set*) s)
+#define MAKE_FDSET(s) ((FDSet*) s)
+
+FDSet *fdset_new(void) {
+ return MAKE_FDSET(set_new(NULL));
+}
+
+static void fdset_shallow_freep(FDSet **s) {
+ /* Destroys the set, but does not free the fds inside, like fdset_free()! */
+ set_free(MAKE_SET(*ASSERT_PTR(s)));
+}
+
+int fdset_new_array(FDSet **ret, const int fds[], size_t n_fds) {
+ _cleanup_(fdset_shallow_freep) FDSet *s = NULL;
+ int r;
+
+ assert(ret);
+ assert(fds || n_fds == 0);
+
+ s = fdset_new();
+ if (!s)
+ return -ENOMEM;
+
+ for (size_t i = 0; i < n_fds; i++) {
+ r = fdset_put(s, fds[i]);
+ if (r < 0)
+ return r;
+ }
+
+ *ret = TAKE_PTR(s);
+ return 0;
+}
+
+void fdset_close(FDSet *s) {
+ void *p;
+
+ while ((p = set_steal_first(MAKE_SET(s)))) {
+ int fd = PTR_TO_FD(p);
+
+ /* Valgrind's fd might have ended up in this set here, due to fdset_new_fill(). We'll ignore
+ * all failures here, so that the EBADFD that valgrind will return us on close() doesn't
+ * influence us */
+
+ /* When reloading duplicates of the private bus connection fds and suchlike are closed here,
+ * which has no effect at all, since they are only duplicates. So don't be surprised about
+ * these log messages. */
+
+ if (DEBUG_LOGGING) {
+ _cleanup_free_ char *path = NULL;
+
+ (void) fd_get_path(fd, &path);
+ log_debug("Closing set fd %i (%s)", fd, strna(path));
+ }
+
+ (void) close_nointr(fd);
+ }
+}
+
+FDSet* fdset_free(FDSet *s) {
+ fdset_close(s);
+ set_free(MAKE_SET(s));
+ return NULL;
+}
+
+int fdset_put(FDSet *s, int fd) {
+ assert(s);
+ assert(fd >= 0);
+
+ /* Avoid integer overflow in FD_TO_PTR() */
+ if (fd == INT_MAX)
+ return log_debug_errno(SYNTHETIC_ERRNO(EINVAL), "Refusing invalid fd: %d", fd);
+
+ return set_put(MAKE_SET(s), FD_TO_PTR(fd));
+}
+
+int fdset_consume(FDSet *s, int fd) {
+ int r;
+
+ assert(s);
+ assert(fd >= 0);
+
+ r = fdset_put(s, fd);
+ if (r < 0)
+ safe_close(fd);
+
+ return r;
+}
+
+int fdset_put_dup(FDSet *s, int fd) {
+ _cleanup_close_ int copy = -EBADF;
+ int r;
+
+ assert(s);
+ assert(fd >= 0);
+
+ copy = fcntl(fd, F_DUPFD_CLOEXEC, 3);
+ if (copy < 0)
+ return -errno;
+
+ r = fdset_put(s, copy);
+ if (r < 0)
+ return r;
+
+ return TAKE_FD(copy);
+}
+
+bool fdset_contains(FDSet *s, int fd) {
+ assert(s);
+ assert(fd >= 0);
+
+ /* Avoid integer overflow in FD_TO_PTR() */
+ if (fd == INT_MAX) {
+ log_debug("Refusing invalid fd: %d", fd);
+ return false;
+ }
+
+ return !!set_get(MAKE_SET(s), FD_TO_PTR(fd));
+}
+
+int fdset_remove(FDSet *s, int fd) {
+ assert(s);
+ assert(fd >= 0);
+
+ /* Avoid integer overflow in FD_TO_PTR() */
+ if (fd == INT_MAX)
+ return log_debug_errno(SYNTHETIC_ERRNO(ENOENT), "Refusing invalid fd: %d", fd);
+
+ return set_remove(MAKE_SET(s), FD_TO_PTR(fd)) ? fd : -ENOENT;
+}
+
+int fdset_new_fill(
+ int filter_cloexec, /* if < 0 takes all fds, otherwise only those with O_CLOEXEC set (1) or unset (0) */
+ FDSet **ret) {
+
+ _cleanup_(fdset_shallow_freep) FDSet *s = NULL;
+ _cleanup_closedir_ DIR *d = NULL;
+ int r;
+
+ assert(ret);
+
+ /* Creates an fdset and fills in all currently open file descriptors. Also set all collected fds
+ * to CLOEXEC. */
+
+ d = opendir("/proc/self/fd");
+ if (!d) {
+ if (errno == ENOENT && proc_mounted() == 0)
+ return -ENOSYS;
+
+ return -errno;
+ }
+
+ s = fdset_new();
+ if (!s)
+ return -ENOMEM;
+
+ FOREACH_DIRENT(de, d, return -errno) {
+ int fd;
+
+ if (!IN_SET(de->d_type, DT_LNK, DT_UNKNOWN))
+ continue;
+
+ fd = parse_fd(de->d_name);
+ if (fd < 0)
+ return fd;
+
+ if (fd < 3)
+ continue;
+ if (fd == dirfd(d))
+ continue;
+
+ if (filter_cloexec >= 0) {
+ int fl;
+
+ /* If user asked for that filter by O_CLOEXEC. This is useful so that fds that have
+ * been passed in can be collected and fds which have been created locally can be
+ * ignored, under the assumption that only the latter have O_CLOEXEC set. */
+
+ fl = fcntl(fd, F_GETFD);
+ if (fl < 0)
+ return -errno;
+
+ if (FLAGS_SET(fl, FD_CLOEXEC) != !!filter_cloexec)
+ continue;
+ }
+
+ /* We need to set CLOEXEC manually only if we're collecting non-CLOEXEC fds. */
+ if (filter_cloexec <= 0) {
+ r = fd_cloexec(fd, true);
+ if (r < 0)
+ return r;
+ }
+
+ r = fdset_put(s, fd);
+ if (r < 0)
+ return r;
+ }
+
+ *ret = TAKE_PTR(s);
+ return 0;
+}
+
+int fdset_cloexec(FDSet *fds, bool b) {
+ void *p;
+ int r;
+
+ assert(fds);
+
+ SET_FOREACH(p, MAKE_SET(fds)) {
+ r = fd_cloexec(PTR_TO_FD(p), b);
+ if (r < 0)
+ return r;
+ }
+
+ return 0;
+}
+
+int fdset_new_listen_fds(FDSet **ret, bool unset) {
+ _cleanup_(fdset_shallow_freep) FDSet *s = NULL;
+ int n, fd, r;
+
+ assert(ret);
+
+ /* Creates an fdset and fills in all passed file descriptors */
+
+ s = fdset_new();
+ if (!s)
+ return -ENOMEM;
+
+ n = sd_listen_fds(unset);
+ for (fd = SD_LISTEN_FDS_START; fd < SD_LISTEN_FDS_START + n; fd ++) {
+ r = fdset_put(s, fd);
+ if (r < 0)
+ return r;
+ }
+
+ *ret = TAKE_PTR(s);
+ return 0;
+}
+
+int fdset_to_array(FDSet *fds, int **ret) {
+ unsigned j = 0, m;
+ void *e;
+ int *a;
+
+ assert(ret);
+
+ m = fdset_size(fds);
+ if (m > INT_MAX) /* We want to be able to return an "int" */
+ return -ENOMEM;
+ if (m == 0) {
+ *ret = NULL; /* suppress array allocation if empty */
+ return 0;
+ }
+
+ a = new(int, m);
+ if (!a)
+ return -ENOMEM;
+
+ SET_FOREACH(e, MAKE_SET(fds))
+ a[j++] = PTR_TO_FD(e);
+
+ assert(j == m);
+
+ *ret = TAKE_PTR(a);
+ return (int) m;
+}
+
+int fdset_close_others(FDSet *fds) {
+ _cleanup_free_ int *a = NULL;
+ int n;
+
+ n = fdset_to_array(fds, &a);
+ if (n < 0)
+ return n;
+
+ return close_all_fds(a, n);
+}
+
+unsigned fdset_size(FDSet *fds) {
+ return set_size(MAKE_SET(fds));
+}
+
+bool fdset_isempty(FDSet *fds) {
+ return set_isempty(MAKE_SET(fds));
+}
+
+int fdset_iterate(FDSet *s, Iterator *i) {
+ void *p;
+
+ if (!set_iterate(MAKE_SET(s), i, &p))
+ return -ENOENT;
+
+ return PTR_TO_FD(p);
+}
+
+int fdset_steal_first(FDSet *fds) {
+ void *p;
+
+ p = set_steal_first(MAKE_SET(fds));
+ if (!p)
+ return -ENOENT;
+
+ return PTR_TO_FD(p);
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-07-23 11:49:38 +0000