1 files changed, 123 insertions, 0 deletions
diff --git a/debug.h b/debug.h
new file mode 100644
index 00000000..090d5830
--- /dev/null
+++ b/debug.h
@@ -0,0 +1,123 @@
+#ifndef _DEBUG_H
+#define _DEBUG_H
+
+#define DEVELOPER   4
+#define ALPHA       3
+#define BETA        2
+#define RELEASE     1
+#define NO_SEATBELT 0
+
+#ifndef RELEASE_LEVEL
+#define RELEASE_LEVEL RELEASE
+#endif
+
+#if RELEASE_LEVEL >= ALPHA
+#include <cstdlib>              // for `getenv'
+#include <cstring>              // for `strcmp'
+#endif
+
+#if RELEASE_LEVEL >= BETA
+#include <cassert>
+#endif
+
+#if RELEASE_LEVEL >= RELEASE
+#include <iostream>
+#endif
+
+#include <sstream>              // used for constructing exceptions
+
+namespace ledger {
+
+//////////////////////////////////////////////////////////////////////
+//
+// Debugging facilities for Ledger
+//
+// - In developer level, all checking and debugging facilities are
+//   active.
+//
+// - Alpha level does not include performance degrading
+//   VALIDATE calls.
+//
+// - Beta level is like Alpha, but does not include debugging
+//   facilities.
+//
+// - Release level does not include CONFIRM checks, but does include
+//   assert calls.
+//
+// - Running with no seatbelt disables all checking except for normal
+//   syntax and semantic error checking.
+
+#define WARN(x)							\
+  if (ledger::warning_stream)					\
+    *ledger::warning_stream << "Warning: "<< x << std::endl
+
+#define ERR(exc, x) {				\
+    std::ostringstream s;                       \
+    s << x;                                     \
+    throw exc(s.str().c_str());                 \
+  }
+
+#if RELEASE_LEVEL >= ALPHA
+
+#define DEBUG_ENABLED
+
+extern std::ostream * warning_stream;
+extern std::ostream * debug_stream;
+extern bool           free_debug_stream;
+
+inline bool _debug_active(const char * const cls) {
+  char * debug = std::getenv("DEBUG_CLASS");
+  return debug && std::strcmp(debug, cls) == 0;
+}
+
+#define DEBUG_CLASS(cls) static const char * const _debug_cls = (cls)
+
+#define DEBUG(cls) (ledger::_debug_active(cls))
+#define DEBUG_() DEBUG(_debug_cls)
+
+#define DEBUG_PRINT(cls, x)					\
+  if (ledger::debug_stream && ledger::_debug_active(cls)) {	\
+    *ledger::debug_stream << x << std::endl;			\
+  }
+#define DEBUG_PRINT_(x) DEBUG_PRINT(_debug_cls, x)
+
+#define CONFIRM(x) assert(x)
+
+#if RELEASE_LEVEL == DEVELOPER
+#define VALIDATE(x) assert(x)
+#else
+#define VALIDATE(x)
+#endif
+
+#else // RELEASE_LEVEL
+
+#define DEBUG_CLASS(cls)
+#define DEBUG(cls) 0
+#define DEBUG_() 0
+#define DEBUG_PRINT(cls, x)
+#define DEBUG_PRINT_(x)
+
+#define VALIDATE(x)
+
+#if RELEASE_LEVEL == NO_SEATBELT
+
+#undef assert
+#define assert(x)
+#define CONFIRM(x)
+
+#elif RELEASE_LEVEL >= RELEASE
+
+extern std::ostream * warning_stream;
+#define CONFIRM(x)
+
+#elif RELEASE_LEVEL >= BETA
+
+#define CONFIRM(x) assert(x)
+
+#endif
+
+#endif // RELEASE_LEVEL
+
+} // namespace ledger
+
+#endif // _DEBUG_H