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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 14:37:38 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-07 14:37:38 +0000
commitae581a19fbe896a797450b9d9573fb66f2735227 (patch)
tree56c40be8518a29c9351364d13a9676aa83932dc0 /lib/util/locking.c
parentInitial commit. (diff)
downloadsudo-ae581a19fbe896a797450b9d9573fb66f2735227.tar.xz
sudo-ae581a19fbe896a797450b9d9573fb66f2735227.zip
Adding upstream version 1.9.13p3.upstream/1.9.13p3upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r--lib/util/locking.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/lib/util/locking.c b/lib/util/locking.c
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index 0000000..638b082
--- /dev/null
+++ b/lib/util/locking.c
@@ -0,0 +1,143 @@
+/*
+ * SPDX-License-Identifier: ISC
+ *
+ * Copyright (c) 1999-2005, 2007, 2009-2015
+ * Todd C. Miller <Todd.Miller@sudo.ws>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *
+ * Sponsored in part by the Defense Advanced Research Projects
+ * Agency (DARPA) and Air Force Research Laboratory, Air Force
+ * Materiel Command, USAF, under agreement number F39502-99-1-0512.
+ */
+
+/*
+ * This is an open source non-commercial project. Dear PVS-Studio, please check it.
+ * PVS-Studio Static Code Analyzer for C, C++ and C#: http://www.viva64.com
+ */
+
+#include <config.h>
+
+#include <stdlib.h>
+#include <string.h>
+#ifdef HAVE_STDBOOL_H
+# include <stdbool.h>
+#else
+# include "compat/stdbool.h"
+#endif
+#include <errno.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include "sudo_compat.h"
+#include "sudo_util.h"
+#include "sudo_debug.h"
+
+bool
+sudo_lock_file_v1(int fd, int type)
+{
+ return sudo_lock_region_v1(fd, type, 0);
+}
+
+/*
+ * Lock/unlock all or part of a file.
+ */
+#ifdef HAVE_LOCKF
+bool
+sudo_lock_region_v1(int fd, int type, off_t len)
+{
+ int op, rc;
+ off_t oldpos = -1;
+ debug_decl(sudo_lock_region, SUDO_DEBUG_UTIL);
+
+ switch (type) {
+ case SUDO_LOCK:
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: lock %d:%lld",
+ __func__, fd, (long long)len);
+ op = F_LOCK;
+ break;
+ case SUDO_TLOCK:
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: tlock %d:%lld",
+ __func__, fd, (long long)len);
+ op = F_TLOCK;
+ break;
+ case SUDO_UNLOCK:
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: unlock %d:%lld",
+ __func__, fd, (long long)len);
+ op = F_ULOCK;
+ /* Must seek to start of file to unlock the entire thing. */
+ if (len == 0 && (oldpos = lseek(fd, 0, SEEK_CUR)) != -1) {
+ if (lseek(fd, 0, SEEK_SET) == -1) {
+ sudo_debug_printf(
+ SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to seek to beginning");
+ }
+ }
+ break;
+ default:
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: bad lock type %d",
+ __func__, type);
+ errno = EINVAL;
+ debug_return_bool(false);
+ }
+ rc = lockf(fd, op, len);
+ if (oldpos != -1) {
+ if (lseek(fd, oldpos, SEEK_SET) == -1) {
+ sudo_debug_printf(
+ SUDO_DEBUG_ERROR|SUDO_DEBUG_LINENO|SUDO_DEBUG_ERRNO,
+ "unable to restore offset");
+ }
+ }
+ debug_return_bool(rc == 0);
+}
+#else
+bool
+sudo_lock_region_v1(int fd, int type, off_t len)
+{
+ struct flock lock;
+ int func;
+ debug_decl(sudo_lock_file, SUDO_DEBUG_UTIL);
+
+ switch (type) {
+ case SUDO_LOCK:
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: lock %d:%lld",
+ __func__, fd, (long long)len);
+ lock.l_type = F_WRLCK;
+ func = F_SETLKW;
+ break;
+ case SUDO_TLOCK:
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: tlock %d:%lld",
+ __func__, fd, (long long)len);
+ lock.l_type = F_WRLCK;
+ func = F_SETLK;
+ break;
+ case SUDO_UNLOCK:
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: unlock %d:%lld",
+ __func__, fd, (long long)len);
+ lock.l_type = F_UNLCK;
+ func = F_SETLK;
+ break;
+ default:
+ sudo_debug_printf(SUDO_DEBUG_INFO, "%s: bad lock type %d",
+ __func__, type);
+ errno = EINVAL;
+ debug_return_bool(false);
+ }
+ lock.l_start = 0;
+ lock.l_len = len;
+ lock.l_pid = 0;
+ lock.l_whence = len ? SEEK_CUR : SEEK_SET;
+
+ debug_return_bool(fcntl(fd, func, &lock) == 0);
+}
+#endif