Split into multiple files

For multiple reasons the program is now split:
- Make future porting to OpenBSD easier
- Assign header includes to individiual functions
- Make future program extensions easier
- Recompile only changed parts

ram.c

@@ -0,0 +1,51 @@
+#include <stdio.h>
+
+#include "util.h"
+
+const char *
+ram_free(void)
+{
+	long free;
+
+	return (pscanf("/proc/meminfo", "MemFree: %ld kB\n", &free) == 1) ?
+	       bprintf("%f", (float)free / 1024 / 1024) : NULL;
+}
+
+const char *
+ram_perc(void)
+{
+	long total, free, buffers, cached;
+
+	return (pscanf("/proc/meminfo",
+	               "MemTotal: %ld kB\n"
+	               "MemFree: %ld kB\n"
+	               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
+	               "Cached: %ld kB\n",
+	               &total, &free, &buffers, &buffers, &cached) == 5) ?
+	       bprintf("%d", 100 * ((total - free) - (buffers + cached)) / total) :
+	       NULL;
+}
+
+const char *
+ram_total(void)
+{
+	long total;
+
+	return (pscanf("/proc/meminfo", "MemTotal: %ld kB\n", &total) == 1) ?
+	       bprintf("%f", (float)total / 1024 / 1024) : NULL;
+}
+
+const char *
+ram_used(void)
+{
+	long total, free, buffers, cached;
+
+	return (pscanf("/proc/meminfo",
+	               "MemTotal: %ld kB\n"
+	               "MemFree: %ld kB\n"
+	               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
+	               "Cached: %ld kB\n",
+	               &total, &free, &buffers, &buffers, &cached) == 5) ?
+	       bprintf("%f", (float)(total - free - buffers - cached) / 1024 / 1024) :
+	       NULL;
+}