From 65a0de8fbf14f74ab4f452f05decc1a280c8e498 Mon Sep 17 00:00:00 2001
From: Joachim Wiberg <troglobit@gmail.com>
Date: Wed, 20 Dec 2023 23:26:54 +0100
Subject: [PATCH] Add fsmon.c, missing from previous commit

Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
---
 src/fsmon.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 120 insertions(+)
 create mode 100644 src/fsmon.c

diff --git a/src/fsmon.c b/src/fsmon.c
new file mode 100644
index 0000000..496316d
--- /dev/null
+++ b/src/fsmon.c
@@ -0,0 +1,120 @@
+/* File system monitor
+ *
+ * Copyright (C) 2015-2023  Joachim Wiberg <troglobit@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or 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.
+ */
+
+#include <sys/statvfs.h>
+#include "wdt.h"
+#include "script.h"
+
+static const char *fsname = NULL;
+static char *exec = NULL;
+static int logmark = 0;
+static uev_t watcher;
+
+/* Default: disabled -- recommended 0.95, 1.0 */
+static double warning  = 0.0;
+static double critical = 0.0;
+
+
+static void cb(uev_t *w, void *arg, int events)
+{
+	long unsigned int bused, fused;
+	double blevel, flevel;
+	struct statvfs f;
+
+	if (statvfs(fsname, &f)) {
+		PERROR("Failed statfs(%s)", fsname);
+		return;
+	}
+
+	bused  = f.f_blocks - f.f_bavail;
+	blevel = (double)(bused) / (double)(f.f_blocks);
+	fused  = f.f_files - f.f_ffree;
+	flevel = (double)(fused) / (double)(f.f_files);
+
+	LOG("Fsmon %s: blocks %.0f%%, inodes %.0f%%, warning: %.0f%%, critical: %.0f%%",
+	    fsname, blevel * 100, flevel * 100, warning * 100, critical * 100);
+	if (logmark) {
+		const char *ro = "(read-only";
+
+		LOG("Fsmon %s: blocks %lu/%lu inodes %lu/%lu %s", fsname,
+		    bused, f.f_bavail,
+		    fused, f.f_ffree,
+		    (f.f_flag & ST_RDONLY) ? ro : "");
+	}
+
+	if (blevel > warning || flevel > warning) {
+		double level = blevel;
+
+		if (flevel > blevel) {
+			level = flevel;
+			setenv("FSMON_TYPE", "inodes", 1);
+		} else
+			setenv("FSMON_TYPE", "blocks", 1);
+		setenv("FSMON_NAME", fsname, 1);
+
+		if (critical > 0.0 && (blevel > critical || flevel > warning)) {
+			EMERG("File system %s usage too high, blocks %.2f > %0.2f, or inodes %.2f > %0.2f, rebooting system ...",
+			      fsname, blevel, critical, flevel, critical);
+			if (checker_exec(exec, "fsmon", 1, level, warning, critical))
+				wdt_forced_reset(w->ctx, getpid(), PACKAGE ":fsmon", 0);
+		} else {
+			WARN("File system %s use very high, blocks %.2f > %0.2f, inodes %.2f > %0.2f",
+			     fsname, blevel, warning, flevel, warning);
+			checker_exec(exec, "fsmon", 0, level, warning, critical);
+		}
+
+		unsetenv("FSMON_TYPE");
+		unsetenv("FSMON_NAME");
+	}
+}
+
+int fsmon_init(uev_ctx_t *ctx, const char *name, int T, int mark,
+	       float warn, float crit, char *script)
+{
+	if (!name)
+		name = "/";
+
+	if (!T) {
+		INFO("File descriptor leak monitor disabled.");
+		return uev_timer_stop(&watcher);
+	}
+
+	LOG("File system monitor: %s period %d sec, warning: %.2f%%, reboot: %.2f%%",
+	     name, T, warning * 100, critical * 100);
+
+	if (fsname)
+		free(fsname);
+	fsname = strdup(name);
+	logmark = mark;
+	warning = warn;
+	critical = crit;
+	if (script) {
+		if (exec)
+			free(exec);
+		exec = strdup(script);
+	}
+
+	uev_timer_stop(&watcher);
+	return uev_timer_init(ctx, &watcher, cb, NULL, 1000, T * 1000);
+}
+
+/**
+ * Local Variables:
+ *  c-file-style: "linux"
+ *  indent-tabs-mode: t
+ * End:
+ */