service_runtime/nacl_log.c

   1 /*
   2  * Copyright 2008, Google Inc.
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met:
   8  *
   9  *     * Redistributions of source code must retain the above copyright
  10  * notice, this list of conditions and the following disclaimer.
  11  *     * Redistributions in binary form must reproduce the above
  12  * copyright notice, this list of conditions and the following disclaimer
  13  * in the documentation and/or other materials provided with the
  14  * distribution.
  15  *     * Neither the name of Google Inc. nor the names of its
  16  * contributors may be used to endorse or promote products derived from
  17  * this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  20  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  21  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  22  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  23  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  25  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  26  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  27  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  28  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  29  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  30  */
  31
  32 /*
  33  * NaCl Server Runtime logging code.
  34  */
  35 #include "native_client/include/portability.h"
  36
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <stdarg.h>
  40
  41 #define NON_THREAD_SAFE_DETAIL_CHECK  1
  42 /*
  43  * If set, check detail_level without grabbing a mutex.  This makes
  44  * logging much cheaper, but implies that the verbosity level should
  45  * only be changed prior to going multithreaded.
  46  */
  47
  48 #include "native_client/service_runtime/gio.h"
  49 #include "native_client/service_runtime/nacl_sync.h"
  50 #include "native_client/service_runtime/nacl_log.h"
  51 #include "native_client/service_runtime/nacl_threads.h"
  52 #include "native_client/service_runtime/nacl_timestamp.h"
  53
  54 static struct NaClMutex  log_mu;
  55
  56 static int              verbosity = 0;
  57 static struct Gio       *log_stream = NULL;
  58 static struct GioFile   log_file_stream;
  59 static int              timestamp_enabled = 1;
  60
  61 void NaClLogModuleInit()
  62 {
  63   NaClMutexCtor(&log_mu);
  64 }
  65
  66 void NaClLogModuleFini()
  67 {
  68   NaClMutexDtor(&log_mu);
  69 }
  70
  71 void NaClLogLock()
  72 {
  73   NaClMutexLock(&log_mu);
  74 }
  75
  76 void NaClLogUnlock(void)
  77 {
  78   NaClMutexUnlock(&log_mu);
  79 }
  80
  81 static INLINE struct Gio *NaClLogGetGio_mu()
  82 {
  83   if (NULL == log_stream) {
  84     (void) GioFileRefCtor(&log_file_stream, stderr);
  85     log_stream = (struct Gio *) &log_file_stream;
  86   }
  87   return log_stream;
  88 }
  89
  90 void  NaClLogSetVerbosity(int verb)
  91 {
  92   NaClLogLock();
  93   verbosity = verb;
  94   NaClLogUnlock();
  95 }
  96
  97 void  NaClLogIncrVerbosity(void)
  98 {
  99   NaClLogLock();
 100   ++verbosity;
 101   NaClLogUnlock();
 102 }
 103
 104 int NaClLogGetVerbosity(void)
 105 {
 106   int v;
 107
 108   NaClLogLock();
 109   v = verbosity;
 110   NaClLogUnlock();
 111
 112   return v;
 113 }
 114
 115 void  NaClLogSetGio(struct Gio *stream)
 116 {
 117   NaClLogLock();
 118   if (NULL != log_stream) {
 119     (void) (*log_stream->vtbl->Flush)(log_stream);
 120   }
 121   log_stream = stream;
 122   NaClLogUnlock();
 123 }
 124
 125 struct Gio  *NaClLogGetGio(void)
 126 {
 127   struct Gio  *s;
 128
 129   NaClLogLock();
 130   s = NaClLogGetGio_mu();
 131   NaClLogUnlock();
 132
 133   return s;
 134 }
 135
 136 void NaClLogEnableTimestamp(void)
 137 {
 138   timestamp_enabled = 1;
 139 }
 140
 141 void NaClLogDisableTimestamp(void)
 142 {
 143   timestamp_enabled = 0;
 144 }
 145
 146 /*
 147  * Output a printf-style formatted message if the log verbosity level
 148  * is set higher than the log output's detail level.  Note that since
 149  * this is not a macro, log message arguments that have side effects
 150  * will have their side effects regardless of whether the
 151  * corresponding log message is printed or not.  This is good from a
 152  * consistency point of view, but it means that should a logging
 153  * argument be expensive to compute, the log statement needs to be
 154  * surrounded by something like
 155  *
 156  *  if (detail_level <= NaClLogGetVerbosity()) {
 157  *    NaClLog(detail_level, "format string", expensive_arg(), ...);
 158  *  }
 159  *
 160  * The log message, if written, is prepended by a microsecond
 161  * resolution timestamp on linux and a millisecond resolution
 162  * timestamp on windows.  This means that if the NaCl app can read its
 163  * own logs, it can distinguish which host OS it is running on.
 164  */
 165 void  NaClLogV_mu(int     detail_level,
 166                   char    *fmt,
 167                   va_list ap)
 168 {
 169   struct Gio  *s;
 170   char        timestamp[128];
 171
 172   s = NaClLogGetGio_mu();
 173
 174   if (detail_level <= verbosity) {
 175     if (timestamp_enabled) {
 176       int pid;
 177       pid = GETPID();
 178       gprintf(s, "[%d,%u:%s] ",
 179               pid,
 180               NaClThreadId(),
 181               NaClTimeStampString(timestamp, sizeof timestamp));
 182     }
 183
 184     (void) gvprintf(s, fmt, ap);
 185     (void) (*s->vtbl->Flush)(s);
 186   }
 187
 188   if (LOG_FATAL == detail_level) {
 189     abort();
 190   }
 191 }
 192
 193 void NaClLogV(int     detail_level,
 194               char    *fmt,
 195               va_list ap)
 196 {
 197 #if NON_THREAD_SAFE_DETAIL_CHECK
 198   if (detail_level > verbosity) {
 199     return;
 200   }
 201 #endif
 202   NaClLogLock();
 203   NaClLogV_mu(detail_level, fmt, ap);
 204   NaClLogUnlock();
 205 }
 206
 207 void  NaClLog(int   detail_level,
 208               char  *fmt,
 209               ...)
 210 {
 211   va_list ap;
 212
 213 #if NON_THREAD_SAFE_DETAIL_CHECK
 214   if (detail_level > verbosity) {
 215     return;
 216   }
 217 #endif
 218
 219   NaClLogLock();
 220   va_start(ap, fmt);
 221   NaClLogV_mu(detail_level, fmt, ap);
 222   va_end(ap);
 223   NaClLogUnlock();
 224 }