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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 11:48:22 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-13 11:48:22 +0000
commit7373ce3d6988706388f136e1c06afd20a3e8d5be (patch)
treee9ae5af7d102667e5706187646db45de8238e8c4 /lib/maxfd.c
parentInitial commit. (diff)
downloadmonitoring-plugins-upstream.tar.xz
monitoring-plugins-upstream.zip
Adding upstream version 2.3.5.upstream/2.3.5upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/maxfd.c')
-rw-r--r--lib/maxfd.c26
1 files changed, 26 insertions, 0 deletions
diff --git a/lib/maxfd.c b/lib/maxfd.c
new file mode 100644
index 0000000..529b356
--- /dev/null
+++ b/lib/maxfd.c
@@ -0,0 +1,26 @@
+#include "./maxfd.h"
+#include <errno.h>
+
+long mp_open_max (void) {
+ long maxfd = 0L;
+ /* Try sysconf(_SC_OPEN_MAX) first, as it can be higher than OPEN_MAX.
+ * If that fails and the macro isn't defined, we fall back to an educated
+ * guess. There's no guarantee that our guess is adequate and the program
+ * will die with SIGSEGV if it isn't and the upper boundary is breached. */
+
+#ifdef _SC_OPEN_MAX
+ errno = 0;
+ if ((maxfd = sysconf (_SC_OPEN_MAX)) < 0) {
+ if (errno == 0)
+ maxfd = DEFAULT_MAXFD; /* it's indeterminate */
+ else
+ die (STATE_UNKNOWN, _("sysconf error for _SC_OPEN_MAX\n"));
+ }
+#elif defined(OPEN_MAX)
+ return OPEN_MAX
+#else /* sysconf macro unavailable, so guess (may be wildly inaccurate) */
+ return DEFAULT_MAXFD;
+#endif
+
+ return(maxfd);
+}