Implement dmesg.

1 files changed, 40 insertions, 0 deletions

diff --git a/toys/dmesg.c b/toys/dmesg.c
new file mode 100644
index 00000000..7a150121
--- /dev/null
+++ b/toys/dmesg.c
@@ -0,0 +1,40 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * dmesg.c - display/control kernel ring buffer.
+ *
+ * Copyright 2006 Rob Landley <rob@landley.net>
+ */
+
+#include "toys.h"
+#include <sys/klog.h>
+
+#define TT toy.dmesg
+
+int dmesg_main(void)
+{
+	// For -n just tell kernel to which messages to keep.
+	if (toys.optflags & 2) {
+		if (klogctl(8, NULL, TT.level))
+			error_exit("klogctl");
+	} else {
+		int size, i, last = '\n';
+		char *data;
+
+		// Figure out how much data we need, and fetch it.
+		size = TT.size;
+		if (size<2) size = 16384;
+		data = xmalloc(size);
+		size = klogctl(3 + (toys.optflags&1), data, size);
+		if (size < 0) error_exit("klogctl");
+
+		// Display data, filtering out level markers.
+		for (i=0; i<size; ) {
+			if (last=='\n' && data[i]=='<') i += 3;
+			else putchar(last = data[i++]);
+		}
+		if (last!='\n') putchar('\n');
+		if (CFG_TOYBOX_FREE) free(data);
+	}
+
+	return 0;
+}