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authorPeter Bui <pnutzh4x0r@gmail.com>2011-02-26 17:45:12 -0500
committerMichael Stapelberg <michael@stapelberg.de>2011-05-06 13:13:11 +0200
commit8b18e8e33cbefc19f7f011a7ac83820621395b2f (patch)
tree0b7c363218fecae57496b17e572341ab98129dc7 /src/print_cpu_usage.c
parent0a13d304654a63c53f9cffdcd8941b92f3a445fe (diff)
Add print_cpu_usage
Diffstat (limited to 'src/print_cpu_usage.c')
-rw-r--r--src/print_cpu_usage.c50
1 files changed, 50 insertions, 0 deletions
diff --git a/src/print_cpu_usage.c b/src/print_cpu_usage.c
new file mode 100644
index 0000000..d80693d
--- /dev/null
+++ b/src/print_cpu_usage.c
@@ -0,0 +1,50 @@
+// vim:sw=8:sts=8:ts=8:expandtab
+#include <stdlib.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+
+#include "i3status.h"
+
+static int prev_total = 0;
+static int prev_idle = 0;
+
+/*
+ * Reads the CPU utilization from /proc/stat and returns the usage as a
+ * percentage.
+ *
+ */
+void print_cpu_usage(const char *format) {
+ const char *walk;
+ char buf[1024];
+ int curr_user, curr_nice, curr_system, curr_idle, curr_total;
+ int diff_idle, diff_total, diff_usage;
+
+#if defined(LINUX)
+ static char statpath[512];
+ strcpy(statpath, "/proc/stat");
+ if (!slurp(statpath, buf, sizeof(buf)))
+ die("could not read %s\n", statpath);
+
+ if (sscanf(buf, "cpu %d %d %d %d", &curr_user, &curr_nice, &curr_system, &curr_idle) != 4)
+ die("could not read cpu utilization\n");
+
+ curr_total = curr_user + curr_nice + curr_system + curr_idle;
+ diff_idle = curr_idle - prev_idle;
+ diff_total = curr_total - prev_total;
+ diff_usage = (1000 * (diff_total - diff_idle)/diff_total + 5)/10;
+ prev_total = curr_total;
+ prev_idle = curr_idle;
+#endif
+ for (walk = format; *walk != '\0'; walk++) {
+ if (*walk != '%') {
+ putchar(*walk);
+ continue;
+ }
+
+ if (strncmp(walk+1, "usage", strlen("usage")) == 0) {
+ printf("%02d%%", diff_usage);
+ walk += strlen("usage");
+ }
+ }
+}