mozglue/linker/Logging.h

   1 /* This Source Code Form is subject to the terms of the Mozilla Public
   2  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
   3  * You can obtain one at http://mozilla.org/MPL/2.0/. */
   4
   5 #ifndef Logging_h
   6 #define Logging_h
   7
   8 #include "mozilla/Likely.h"
   9 #include "mozilla/MacroArgs.h"
  10
  11 #ifdef ANDROID
  12 #  include <android/log.h>
  13 #  define LOG(...) \
  14     __android_log_print(ANDROID_LOG_INFO, "GeckoLinker", __VA_ARGS__)
  15 #  define WARN(...) \
  16     __android_log_print(ANDROID_LOG_WARN, "GeckoLinker", __VA_ARGS__)
  17 #  define ERROR(...) \
  18     __android_log_print(ANDROID_LOG_ERROR, "GeckoLinker", __VA_ARGS__)
  19 #else
  20 #  include <cstdio>
  21
  22 /* Expand to 1 or m depending on whether there is one argument or more
  23  * given. */
  24 #  define MOZ_ONE_OR_MORE_ARGS_IMPL2(_1, _2, _3, _4, _5, _6, _7, _8, _9, N, \
  25                                      ...)                                   \
  26     N
  27 #  define MOZ_ONE_OR_MORE_ARGS_IMPL(args) MOZ_ONE_OR_MORE_ARGS_IMPL2 args
  28 #  define MOZ_ONE_OR_MORE_ARGS(...) \
  29     MOZ_ONE_OR_MORE_ARGS_IMPL((__VA_ARGS__, m, m, m, m, m, m, m, m, 1, 0))
  30
  31 #  define MOZ_MACRO_GLUE(a, b) a b
  32
  33 /* Some magic to choose between LOG1 and LOGm depending on the number of
  34  * arguments */
  35 #  define MOZ_CHOOSE_LOG(...)                                          \
  36     MOZ_MACRO_GLUE(MOZ_CONCAT(LOG, MOZ_ONE_OR_MORE_ARGS(__VA_ARGS__)), \
  37                    (__VA_ARGS__))
  38
  39 #  define LOG1(format) fprintf(stderr, format "\n")
  40 #  define LOGm(format, ...) fprintf(stderr, format "\n", __VA_ARGS__)
  41 #  define LOG(...) MOZ_CHOOSE_LOG(__VA_ARGS__)
  42 #  define WARN(...) MOZ_CHOOSE_LOG("Warning: " __VA_ARGS__)
  43 #  define ERROR(...) MOZ_CHOOSE_LOG("Error: " __VA_ARGS__)
  44
  45 #endif
  46
  47 class Logging {
  48  public:
  49   static bool isVerbose() { return Singleton.verbose; }
  50
  51  private:
  52   bool verbose;
  53
  54  public:
  55   static void Init() {
  56     const char* env = getenv("MOZ_DEBUG_LINKER");
  57     if (env && *env == '1') Singleton.verbose = true;
  58   }
  59
  60  private:
  61   static Logging Singleton;
  62 };
  63
  64 #define DEBUG_LOG(...)                        \
  65   do {                                        \
  66     if (MOZ_UNLIKELY(Logging::isVerbose())) { \
  67       LOG(__VA_ARGS__);                       \
  68     }                                         \
  69   } while (0)
  70
  71 #endif /* Logging_h */