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-rw-r--r--toys/lsb/dmesg.c59
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+/* vi: set sw=4 ts=4:
+ *
+ * dmesg.c - display/control kernel ring buffer.
+ *
+ * Copyright 2006, 2007 Rob Landley <rob@landley.net>
+ *
+ * Not in SUSv3.
+
+USE_DMESG(NEWTOY(dmesg, "s#n#c", TOYFLAG_BIN))
+
+config DMESG
+ bool "dmesg"
+ default y
+ help
+ usage: dmesg [-n level] [-s bufsize] | -c
+
+ Print or control the kernel ring buffer.
+
+ -n Set kernel logging level (1-9).
+ -s Size of buffer to read (in bytes), default 16384.
+ -c Clear the ring buffer after printing.
+*/
+
+#include "toys.h"
+#include <sys/klog.h>
+
+DEFINE_GLOBALS(
+ long level;
+ long size;
+)
+
+#define TT this.dmesg
+
+void 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 xputc(last = data[i++]);
+ }
+ if (last!='\n') xputc('\n');
+ if (CFG_TOYBOX_FREE) free(data);
+ }
+}