1 files changed, 72 insertions, 0 deletions
diff --git a/mozglue/linker/Logging.h b/mozglue/linker/Logging.h
new file mode 100644
index 0000000000..1e66ea41de
--- /dev/null
+++ b/mozglue/linker/Logging.h
@@ -0,0 +1,72 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef Logging_h
+#define Logging_h
+
+#include <cstdlib>
+#include "mozilla/Likely.h"
+#include "mozilla/MacroArgs.h"
+
+#ifdef ANDROID
+#  include <android/log.h>
+#  define LOG(...) \
+    __android_log_print(ANDROID_LOG_INFO, "GeckoLinker", __VA_ARGS__)
+#  define WARN(...) \
+    __android_log_print(ANDROID_LOG_WARN, "GeckoLinker", __VA_ARGS__)
+#  define ERROR(...) \
+    __android_log_print(ANDROID_LOG_ERROR, "GeckoLinker", __VA_ARGS__)
+#else
+#  include <cstdio>
+
+/* Expand to 1 or m depending on whether there is one argument or more
+ * given. */
+#  define MOZ_ONE_OR_MORE_ARGS_IMPL2(_1, _2, _3, _4, _5, _6, _7, _8, _9, N, \
+                                     ...)                                   \
+    N
+#  define MOZ_ONE_OR_MORE_ARGS_IMPL(args) MOZ_ONE_OR_MORE_ARGS_IMPL2 args
+#  define MOZ_ONE_OR_MORE_ARGS(...) \
+    MOZ_ONE_OR_MORE_ARGS_IMPL((__VA_ARGS__, m, m, m, m, m, m, m, m, 1, 0))
+
+#  define MOZ_MACRO_GLUE(a, b) a b
+
+/* Some magic to choose between LOG1 and LOGm depending on the number of
+ * arguments */
+#  define MOZ_CHOOSE_LOG(...)                                          \
+    MOZ_MACRO_GLUE(MOZ_CONCAT(LOG, MOZ_ONE_OR_MORE_ARGS(__VA_ARGS__)), \
+                   (__VA_ARGS__))
+
+#  define LOG1(format) fprintf(stderr, format "\n")
+#  define LOGm(format, ...) fprintf(stderr, format "\n", __VA_ARGS__)
+#  define LOG(...) MOZ_CHOOSE_LOG(__VA_ARGS__)
+#  define WARN(...) MOZ_CHOOSE_LOG("Warning: " __VA_ARGS__)
+#  define ERROR(...) MOZ_CHOOSE_LOG("Error: " __VA_ARGS__)
+
+#endif
+
+class Logging {
+ public:
+  static bool isVerbose() { return Singleton.verbose; }
+
+ private:
+  bool verbose;
+
+ public:
+  static void Init() {
+    const char* env = getenv("MOZ_DEBUG_LINKER");
+    if (env && *env == '1') Singleton.verbose = true;
+  }
+
+ private:
+  static Logging Singleton;
+};
+
+#define DEBUG_LOG(...)                        \
+  do {                                        \
+    if (MOZ_UNLIKELY(Logging::isVerbose())) { \
+      LOG(__VA_ARGS__);                       \
+    }                                         \
+  } while (0)
+
+#endif /* Logging_h */