"mount" now reports errors from nfsmount() and assumes NFS mount
[oweals/busybox.git] / util-linux / dmesg.c
index 64265b473e6049a560f324ae2c70f0067570dbc1..c4f4fb408f6810c23f82ae0b236ac46095d9fca9 100644 (file)
-#include "internal.h"
-#include <stdlib.h>
-#include <unistd.h>
-#include <time.h>
-
+/* vi: set sw=4 ts=4: */
 /* dmesg.c -- Print out the contents of the kernel ring buffer
  * Created: Sat Oct  9 16:19:47 1993
  * Revised: Thu Oct 28 21:52:17 1993 by faith@cs.unc.edu
  * Copyright 1993 Theodore Ts'o (tytso@athena.mit.edu)
  * This program comes with ABSOLUTELY NO WARRANTY.
  * Modifications by Rick Sladkey (jrs@world.std.com)
- * from util-linux; adapted for busybox
+ * Larger buffersize 3 June 1998 by Nicolai Langfeldt, based on a patch
+ * by Peeter Joot.  This was also suggested by John Hudson.
+ * 1999-02-22 Arkadiusz Mi¶kiewicz <misiek@misiek.eu.org>
+ * - added Native Language Support
+ *
+ * from util-linux -- adapted for busybox by 
+ * Erik Andersen <andersee@debian.org>. I ripped out Native Language 
+ * Support, replaced getopt, added some gotos for redundant stuff.
  */
 
+#include "internal.h"
 #include <linux/unistd.h>
 #include <stdio.h>
+#include <stdlib.h>
 
-#define __NR_klog __NR_syslog
-
-#if defined(__GLIBC__)
-#include <sys/klog.h>
-#define klog klogctl
-#else
-static inline _syscall3 (int, klog, int, type, char *, b, int, len)
-#endif                         /* __GLIBC__ */
+#if __GNU_LIBRARY__ < 5
 
+#ifndef __alpha__
+# define __NR_klogctl __NR_syslog
+static inline _syscall3(int, klogctl, int, type, char *, b, int, len);
+#else                                                  /* __alpha__ */
+#define klogctl syslog
+#endif
 
+#else
+# include <sys/klog.h>
+#endif
 
-static const char dmesg_usage[] = "dmesg [-c] [-n level]\n";
+static const char dmesg_usage[] = "dmesg [-c] [-n LEVEL] [-s SIZE]\n"
+#ifndef BB_FEATURE_TRIVIAL_HELP
+       "\nPrints or controls the kernel ring buffer\n\n"
+       "Options:\n"
+       "\t-c\t\tClears the ring buffer's contents after printing\n"
+       "\t-n LEVEL\tSets console logging level\n"
+       "\t-s SIZE\t\tUse a buffer of size SIZE\n"
+#endif
+       ;
 
-int dmesg_main (int argc, char **argv)
+int dmesg_main(int argc, char **argv)
 {
+       char *buf;
+       int bufsize = 8196;
+       int i;
+       int n;
+       int level = 0;
+       int lastc;
+       int cmd = 3;
+       int stopDoingThat;
 
-    char buf[4096];
-    int i;
-    int n;
-    int level = 0;
-    int lastc;
-    int cmd = 3;
+       argc--;
+       argv++;
 
-    argc--;
-    argv++;
+       /* Parse any options */
+       while (argc && **argv == '-') {
+               stopDoingThat = FALSE;
+               while (stopDoingThat == FALSE && *++(*argv)) {
+                       switch (**argv) {
+                       case 'c':
+                               cmd = 4;
+                               break;
+                       case 'n':
+                               cmd = 8;
+                               if (--argc == 0)
+                                       goto end;
+                               level = atoi(*(++argv));
+                               if (--argc > 0)
+                                       ++argv;
+                               stopDoingThat = TRUE;
+                               break;
+                       case 's':
+                               if (--argc == 0)
+                                       goto end;
+                               bufsize = atoi(*(++argv));
+                               if (--argc > 0)
+                                       ++argv;
+                               stopDoingThat = TRUE;
+                               break;
+                       default:
+                               goto end;
+                       }
+               }
+       }
 
-    /* Parse any options */
-    while (argc && **argv == '-') {
-       while (*++(*argv))
-           switch (**argv) {
-           case 'c':
-               cmd = 4;
-               break;
-           case 'n':
-               cmd = 8;
-               if (--argc == 0)
-                   goto end;
-               level = atoi (*(++argv));
-               --argc;
-               ++argv;
-               break;
-           default:
+       if (argc > 1) {
                goto end;
-           }
-    }
-
-    if (cmd == 8) {
-       n = klog (cmd, NULL, level);
-       if (n < 0) {
-           perror ("klog");
-           exit (FALSE);
        }
-       exit (TRUE);
-    }
 
-    n = klog (cmd, buf, sizeof (buf));
-    if (n < 0) {
-       perror ("klog");
-       exit (FALSE);
-    }
+       if (cmd == 8) {
+               n = klogctl(cmd, NULL, level);
+               if (n < 0) {
+                       goto klogctl_error;
+               }
+               exit(TRUE);
+       }
 
-    lastc = '\n';
-    for (i = 0; i < n; i++) {
-       if ((i == 0 || buf[i - 1] == '\n') && buf[i] == '<') {
-           i++;
-           while (buf[i] >= '0' && buf[i] <= '9')
-               i++;
-           if (buf[i] == '>')
-               i++;
+       if (bufsize < 4096)
+               bufsize = 4096;
+       buf = (char *) xmalloc(bufsize);
+       n = klogctl(cmd, buf, bufsize);
+       if (n < 0) {
+               goto klogctl_error;
        }
-       lastc = buf[i];
-       putchar (lastc);
-    }
-    if (lastc != '\n')
-       putchar ('\n');
-    exit (TRUE);
 
+       lastc = '\n';
+       for (i = 0; i < n; i++) {
+               if ((i == 0 || buf[i - 1] == '\n') && buf[i] == '<') {
+                       i++;
+                       while (buf[i] >= '0' && buf[i] <= '9')
+                               i++;
+                       if (buf[i] == '>')
+                               i++;
+               }
+               lastc = buf[i];
+               putchar(lastc);
+       }
+       if (lastc != '\n')
+               putchar('\n');
+       exit(TRUE);
   end:
-    fprintf (stderr, "Usage: %s\n", dmesg_usage);
-    exit (FALSE);
+       usage(dmesg_usage);
+       exit(FALSE);
+  klogctl_error:
+       perror("klogctl");
+       exit(FALSE);
+
 }