1 files changed, 105 insertions, 0 deletions
diff --git a/collectors/proc.plugin/proc_uptime.c b/collectors/proc.plugin/proc_uptime.c
new file mode 100644
index 000000000..142ae2d0c
--- /dev/null
+++ b/collectors/proc.plugin/proc_uptime.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "plugin_proc.h"
+
+static inline collected_number uptime_from_boottime(void) {
+#ifdef CLOCK_BOOTTIME_IS_AVAILABLE
+    return now_boottime_usec() / 1000;
+#else
+    error("uptime cannot be read from CLOCK_BOOTTIME on this system.");
+    return 0;
+#endif
+}
+
+static procfile *read_proc_uptime_ff = NULL;
+static inline collected_number read_proc_uptime(void) {
+    if(unlikely(!read_proc_uptime_ff)) {
+        char filename[FILENAME_MAX + 1];
+        snprintfz(filename, FILENAME_MAX, "%s%s", netdata_configured_host_prefix, "/proc/uptime");
+
+        read_proc_uptime_ff = procfile_open(config_get("plugin:proc:/proc/uptime", "filename to monitor", filename), " \t", PROCFILE_FLAG_DEFAULT);
+        if(unlikely(!read_proc_uptime_ff)) return 0;
+    }
+
+    read_proc_uptime_ff = procfile_readall(read_proc_uptime_ff);
+    if(unlikely(!read_proc_uptime_ff)) return 0;
+
+    if(unlikely(procfile_lines(read_proc_uptime_ff) < 1)) {
+        error("/proc/uptime has no lines.");
+        return 0;
+    }
+    if(unlikely(procfile_linewords(read_proc_uptime_ff, 0) < 1)) {
+        error("/proc/uptime has less than 1 word in it.");
+        return 0;
+    }
+
+    return (collected_number)(strtold(procfile_lineword(read_proc_uptime_ff, 0, 0), NULL) * 1000.0);
+}
+
+int do_proc_uptime(int update_every, usec_t dt) {
+    (void)dt;
+
+    static int use_boottime = -1;
+
+    if(unlikely(use_boottime == -1)) {
+        collected_number uptime_boottime = uptime_from_boottime();
+        collected_number uptime_proc     = read_proc_uptime();
+
+        long long delta = (long long)uptime_boottime - (long long)uptime_proc;
+        if(delta < 0) delta = -delta;
+
+        if(delta <= 1000 && uptime_boottime != 0) {
+            procfile_close(read_proc_uptime_ff);
+            info("Using now_boottime_usec() for uptime (dt is %lld ms)", delta);
+            use_boottime = 1;
+        }
+        else if(uptime_proc != 0) {
+            info("Using /proc/uptime for uptime (dt is %lld ms)", delta);
+            use_boottime = 0;
+        }
+        else {
+            error("Cannot find any way to read uptime on this system.");
+            return 1;
+        }
+    }
+
+    collected_number uptime;
+    if(use_boottime)
+        uptime = uptime_from_boottime();
+    else
+        uptime = read_proc_uptime();
+
+
+    // --------------------------------------------------------------------
+
+    static RRDSET *st = NULL;
+    static RRDDIM *rd = NULL;
+
+    if(unlikely(!st)) {
+
+        st = rrdset_create_localhost(
+                "system"
+                , "uptime"
+                , NULL
+                , "uptime"
+                , NULL
+                , "System Uptime"
+                , "seconds"
+                , PLUGIN_PROC_NAME
+                , "/proc/uptime"
+                , NETDATA_CHART_PRIO_SYSTEM_UPTIME
+                , update_every
+                , RRDSET_TYPE_LINE
+        );
+
+        rd = rrddim_add(st, "uptime", NULL, 1, 1000, RRD_ALGORITHM_ABSOLUTE);
+    }
+    else
+        rrdset_next(st);
+
+    rrddim_set_by_pointer(st, rd, uptime);
+
+    rrdset_done(st);
+
+    return 0;
+}