From 9bd2e1896e2660bf39128ec2920e93e077fe0be9 Mon Sep 17 00:00:00 2001
From: Rob Landley <rob@landley.net>
Date: Mon, 15 Jul 2013 13:12:08 -0500
Subject: klogd, submitted by Ashwini Sharma.

---
 toys/pending/klogd.c | 175 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 175 insertions(+)
 create mode 100644 toys/pending/klogd.c

diff --git a/toys/pending/klogd.c b/toys/pending/klogd.c
new file mode 100644
index 00000000..2fa36820
--- /dev/null
+++ b/toys/pending/klogd.c
@@ -0,0 +1,175 @@
+/* klogd.c - Klogd, The kernel log Dameon.
+ *
+ * Copyright 2012 Sandeep Sharma <sandeep.jack2756@gmail.com>
+ *
+ * No standard
+
+USE_KLOGD(NEWTOY(klogd, "c#<1>8n", TOYFLAG_SBIN))
+
+config KLOGD
+    bool "klogd"
+    default y
+    help
+    usage: klogd [-n] [-c N]
+
+    -c  N   Print to console messages more urgent than prio N (1-8)"
+    -n    Run in foreground.
+
+config KLOGD_SOURCE_RING_BUFFER
+    bool "enable kernel ring buffer as log source."
+    default n
+    depends on KLOGD
+*/
+
+#define FOR_klogd
+#include "toys.h"
+#include <signal.h>
+GLOBALS(
+  long level;
+  int fd;
+)
+
+#if CFG_KLOGD_SOURCE_RING_BUFFER    
+#include <sys/klog.h>
+/*
+ * Open klogd with ring buffer as log source
+ */
+static void open_klogd(void)  
+{
+  syslog(LOG_NOTICE, "KLOGD: started with Kernel ring buffer as log source\n");
+  klogctl(1, NULL, 0);
+}
+/*
+ * Read kernel ring buffer
+ */
+static int read_klogd(char *bufptr, int len)
+{
+  return klogctl(2, bufptr, len);
+}
+/*
+ * Set log level to LEVEL
+ */
+static void set_log_level(int level)
+{   
+  klogctl(8, NULL, level);
+}
+/*
+ * Close klog
+ */
+static void close_klogd(void)
+{
+  klogctl(7, NULL, 0); 
+  klogctl(0, NULL, 0);
+}
+#else
+#include<paths.h>
+#ifndef _PATH_KLOG
+#error "_PATH_KLOG is not known"
+#endif
+/*
+ * Open klog with /proc/kmsg as log source
+ */
+static void open_klogd(void)
+{
+  TT.fd = xopen(_PATH_KLOG, O_RDONLY);
+  syslog(LOG_NOTICE, "KLOGD: started with /proc/kmsg as log source\n");
+}
+/*
+ * Read log to local buffer
+ */
+static int read_klogd(char *bufptr, int len)
+{
+  return xread(TT.fd, bufptr, len);
+}
+/*
+ * Set log level to LEVEL by writing to PATH_PRINTK
+ */
+static void set_log_level(int level)
+{
+    FILE *fptr = xfopen("/proc/sys/kernel/printk", "w");
+    fprintf(fptr, "%u\n", level);
+    fclose(fptr);
+    fptr = NULL;
+}
+/* 
+ * set log level while exiting
+ */
+static void close_klogd(void)
+{
+  set_log_level(7);
+  xclose(TT.fd);
+}
+#endif
+/*
+ * Handle signals
+ */
+static void handle_signal(int sig)
+{
+  close_klogd();
+  syslog(LOG_NOTICE,"KLOGD: Daemon exiting......");
+  exit(1);
+}
+
+static int go_daemon(void)
+{                
+  int fd;        
+
+  fd = open("/dev/null", O_RDWR);
+  if (fd < 0) fd = open("/", O_RDONLY, 0666);
+  pid_t pid = fork();
+
+  if (pid < 0) { 
+    error_msg("DAEMON: fail to fork");
+    return -1;   
+  }              
+  if (pid) exit(EXIT_SUCCESS);
+
+  setsid();      
+  dup2(fd, 0);   
+  dup2(fd, 1);   
+  dup2(fd, 2);   
+  if (fd > 2) close(fd);   
+  return 0;      
+}
+
+/*
+ * Read kernel ring buffer in local buff and keep track of
+ * "used" amount to track next read to start.
+ */
+void klogd_main(void)
+{
+  char msg_buffer[16348]; //LOG_LINE_LENGTH - Ring buffer size
+  int prio, size;
+  int used = 0;
+  char *start, *line_start;
+
+  sigatexit(handle_signal);
+  if(toys.optflags & FLAG_c) set_log_level(TT.level);    //set log level
+  if(!(toys.optflags & FLAG_n)) go_daemon();        //Make it daemon
+  open_klogd();    
+  openlog("Kernel", 0, LOG_KERN);    //open connection to system logger..
+
+  while(1) {
+    start = msg_buffer + used; //start updated for re-read.
+    size = read_klogd(start, sizeof(msg_buffer)-1-used);
+    if (size < 0) perror_exit("error reading file:");
+    start[size] = '\0';  //Ensure last line to be NUL terminated.
+    if(used) start = msg_buffer;
+    while(1) {
+      if((line_start = strsep(&start, "\n")) != NULL && start != NULL) used = 0;
+      else {                            //Incomplete line, copy it to start of buff.
+        used = strlen(line_start);
+        strcpy(msg_buffer, line_start);
+        if(used < (sizeof(msg_buffer) - 1)) break;
+        used = 0; //we have buffer full, log it as it is.
+      }
+      prio = LOG_INFO;  //we dont know priority, mark it INFO
+      if(*line_start == '<') {  //we have new line to syslog
+        line_start++;
+        if(line_start) prio = (int)strtoul(line_start, &line_start, 10);
+        if(*line_start == '>') line_start++;
+      }
+      if(*line_start) syslog(prio, "%s", line_start);
+    }
+  }
+}  
-- 
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