Adding upstream version 255.4.upstream/255.4

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

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);
+}