syslogd.tproj/klog_in.c

   1 /*
   2  * Copyright (c) 2004-2011 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. Please obtain a copy of the License at
  10  * http://www.opensource.apple.com/apsl/ and read it before using this
  11  * file.
  12  *
  13  * The Original Code and all software distributed under the License are
  14  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  15  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  16  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  18  * Please see the License for the specific language governing rights and
  19  * limitations under the License.
  20  *
  21  * @APPLE_LICENSE_HEADER_END@
  22  */
  23
  24 #include <sys/types.h>
  25 #include <sys/stat.h>
  26 #include <sys/socket.h>
  27 #include <sys/un.h>
  28 #include <sys/uio.h>
  29 #include <stdio.h>
  30 #include <stdlib.h>
  31 #include <string.h>
  32 #include <fcntl.h>
  33 #include <errno.h>
  34 #include <unistd.h>
  35 #include "daemon.h"
  36
  37 #define forever for(;;)
  38
  39 #define MY_ID "klog_in"
  40 #define BUFF_SIZE 4096
  41
  42 static char inbuf[BUFF_SIZE];
  43 static int bx;
  44 static int kfd = -1;
  45 static dispatch_source_t in_src;
  46 static dispatch_queue_t in_queue;
  47
  48 void
  49 klog_in_acceptdata(int fd)
  50 {
  51         ssize_t len;
  52         uint32_t i;
  53         char *p, *q;
  54         aslmsg m;
  55
  56         len = read(fd, inbuf + bx, BUFF_SIZE - bx);
  57         if (len <= 0) return;
  58
  59         p = inbuf;
  60         q = p + bx;
  61
  62         for (i = 0; i < len; i++, q++)
  63         {
  64                 if (*q == '\n')
  65                 {
  66                         *q = '\0';
  67                         m = asl_input_parse(p, q - p, NULL, SOURCE_KERN);
  68                         dispatch_async(global.work_queue, ^{ process_message(m, SOURCE_KERN); });
  69                         p = q + 1;
  70                 }
  71         }
  72
  73         if (p != inbuf)
  74         {
  75                 memmove(inbuf, p, BUFF_SIZE - bx - 1);
  76                 bx = q - p;
  77         }
  78 }
  79
  80 int
  81 klog_in_init()
  82 {
  83         static dispatch_once_t once;
  84
  85         dispatch_once(&once, ^{
  86                 in_queue = dispatch_queue_create(MY_ID, NULL);
  87         });
  88
  89         asldebug("%s: init\n", MY_ID);
  90         if (kfd >= 0) return 0;
  91
  92         kfd = open(_PATH_KLOG, O_RDONLY, 0);
  93         if (kfd < 0)
  94         {
  95                 asldebug("%s: couldn't open %s: %s\n", MY_ID, _PATH_KLOG, strerror(errno));
  96                 return -1;
  97         }
  98
  99         if (fcntl(kfd, F_SETFL, O_NONBLOCK) < 0)
 100         {
 101                 close(kfd);
 102                 kfd = -1;
 103                 asldebug("%s: couldn't set O_NONBLOCK for fd %d (%s): %s\n", MY_ID, kfd, _PATH_KLOG, strerror(errno));
 104                 return -1;
 105         }
 106
 107         in_src = dispatch_source_create(DISPATCH_SOURCE_TYPE_READ, (uintptr_t)kfd, 0, in_queue);
 108         dispatch_source_set_event_handler(in_src, ^{ klog_in_acceptdata(kfd); });
 109
 110         dispatch_resume(in_src);
 111         return 0;
 112 }
 113
 114 int
 115 klog_in_close(void)
 116 {
 117         if (kfd < 0) return 1;
 118
 119         dispatch_source_cancel(in_src);
 120         dispatch_release(in_src);
 121         in_src = NULL;
 122
 123         close(kfd);
 124         kfd = -1;
 125
 126         return 0;
 127 }
 128
 129 int
 130 klog_in_reset(void)
 131 {
 132         return 0;
 133 }