[PATCH 5/8] treewide: Suppress clang-tidy warning if we already use O_CLOEXEC or if we can't

[Stefano Brivio <sbrivio@redhat.com>]

In pcap_init(), we open the packet capture file with O_CLOEXEC only
when possible.

In logfile_init() and pidfile_open(), the fact that we pass a third
'mode' argument to open() seems to confuse the android-cloexec-open
checker in LLVM versions from 16 to 19 (at least).

The checker is suggesting to add O_CLOEXEC to 'mode', and not in
'flags', where we already have it.

Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
---
 log.c  | 4 ++++
 pcap.c | 1 +
 util.c | 4 ++++
 3 files changed, 9 insertions(+)

diff --git a/log.c b/log.c
index 6932885..154466f 100644
--- a/log.c
+++ b/log.c
@@ -416,7 +416,11 @@ void logfile_init(const char *name, const char *path, size_t size)
 	if (readlink("/proc/self/exe", exe, PATH_MAX - 1) < 0)
 		die_perror("Failed to read own /proc/self/exe link");
 
+	/* We use O_CLOEXEC here, but clang-tidy as of LLVM 16 to 19 looks for
+	 * it in the 'mode' argument if we have one, so...
+	 */
 	log_file = open(path, O_CREAT | O_TRUNC | O_APPEND | O_RDWR | O_CLOEXEC,
+			/* NOLINTNEXTLINE(android-cloexec-open) */
 			S_IRUSR | S_IWUSR);
 	if (log_file == -1)
 		die_perror("Couldn't open log file %s", path);
diff --git a/pcap.c b/pcap.c
index 6ee6cdf..6753cfb 100644
--- a/pcap.c
+++ b/pcap.c
@@ -167,6 +167,7 @@ void pcap_init(struct ctx *c)
 		return;
 
 	flags |= c->foreground ? O_CLOEXEC : 0;
+	/* NOLINTNEXTLINE(android-cloexec-open): ...only where possible */
 	pcap_fd = open(c->pcap, flags, S_IRUSR | S_IWUSR);
 	if (pcap_fd == -1) {
 		perror("open");
diff --git a/util.c b/util.c
index eff6787..b719f9a 100644
--- a/util.c
+++ b/util.c
@@ -419,7 +419,11 @@ int pidfile_open(const char *path)
 	if (!*path)
 		return -1;
 
+	/* We use O_CLOEXEC here, but clang-tidy as of LLVM 16 to 19 looks for
+	 * it in the 'mode' argument if we have one
+	 */
 	if ((fd = open(path, O_CREAT | O_TRUNC | O_WRONLY | O_CLOEXEC,
+			     /* NOLINTNEXTLINE(android-cloexec-open) */
 			     S_IRUSR | S_IWUSR)) < 0) {
 		perror("PID file open");
 		exit(EXIT_FAILURE);
-- 
@@ -419,7 +419,11 @@ int pidfile_open(const char *path)
 	if (!*path)
 		return -1;
 
+	/* We use O_CLOEXEC here, but clang-tidy as of LLVM 16 to 19 looks for
+	 * it in the 'mode' argument if we have one
+	 */
 	if ((fd = open(path, O_CREAT | O_TRUNC | O_WRONLY | O_CLOEXEC,
+			     /* NOLINTNEXTLINE(android-cloexec-open) */
 			     S_IRUSR | S_IWUSR)) < 0) {
 		perror("PID file open");
 		exit(EXIT_FAILURE);
-- 
2.43.0