Introduce live tracing facility

Set LIBSASS_TRACE to any value
in the environment to watch
a very verbose output live.

Author: saper

Makefile

@@ -120,6 +120,7 @@ SOURCES = \
 	contextualize.cpp \
 	contextualize_eval.cpp \
 	cssize.cpp \
+	debug.cpp \
 	listize.cpp \
 	error_handling.cpp \
 	eval.cpp \

Makefile.am

@@ -48,6 +48,7 @@ libsass_la_SOURCES = \
 	context.cpp context.hpp \
 	contextualize.cpp contextualize.hpp \
 	contextualize_eval.cpp contextualize_eval.hpp \
+	debug.cpp \
 	error_handling.cpp error_handling.hpp \
 	eval.cpp eval.hpp \
 	expand.cpp expand.hpp \

debug.cpp

@@ -0,0 +1,28 @@
+#include <stdio.h>
+#include <sstream>
+
+#include "debug.hpp"
+
+namespace Sass {
+
+  Log::Log() {} 
+
+  std::ostringstream& Log::Get(TLogLevel level, void *p, const char *f, const char *filen, int lineno)
+  {
+	 os << "[LIBSASS] " << p << ":" << f << " " << filen << ":" << lineno << " ";
+	 messageLevel = level;
+	 return os;
+  }
+  std::ostringstream& Log::Get(TLogLevel level, const char *f, const char *filen, int lineno)
+  {
+	 os << "[LIBSASS] " << f << " " << filen << ":" << lineno << " ";
+	 messageLevel = level;
+	 return os;
+  }
+  Log::~Log()
+  {
+	 os << std::endl;
+	 fprintf(stderr, "%s", os.str().c_str());
+	 fflush(stderr);
+  }
+}

debug.hpp

@@ -1,6 +1,7 @@
 #ifndef SASS_DEBUG_H
 #define SASS_DEBUG_H
 
+#define __STDC_LIMIT_MACROS
 #include <stdint.h>
 
 enum dbg_lvl_t : uint32_t {
@@ -12,10 +13,44 @@ enum dbg_lvl_t : uint32_t {
 	EXTEND_COMPOUND = 16,
 	EXTEND_COMPLEX = 32,
 	LCS = 64,
-  EXTEND_OBJECT = 128,
+	EXTEND_OBJECT = 128,
 	ALL = UINT32_MAX
 };
 
+namespace Sass {
+  enum TLogLevel {logINFO, logTRACE};
+  static TLogLevel LibsassLogReportingLevel = getenv("LIBSASS_TRACE") ? logTRACE : logINFO;
+  class Log
+  {
+  public:
+	Log();
+	virtual ~Log();
+	std::ostringstream& Get(TLogLevel level, void *p, const char *f, const char *filen, int lineno);
+	std::ostringstream& Get(TLogLevel level, const char *f, const char *filen, int lineno);
+  public:
+  protected:
+	std::ostringstream os;
+  private:
+	Log(const Log&);
+	Log& operator =(const Log&);
+  private:
+	TLogLevel messageLevel;
+  };
+}
+
+// Visual Studio 2013 does not like __func__
+#if _MSC_VER < 1900
+#define __func__ __FUNCTION__
+#endif
+
+#define TRACE() \
+  if (logTRACE > Sass::LibsassLogReportingLevel) ; \
+  else Sass::Log().Get(Sass::logTRACE, __func__, __FILE__, __LINE__)
+
+#define TRACEINST(obj) \
+  if (logTRACE > Sass::LibsassLogReportingLevel) ; \
+  else Sass::Log().Get(Sass::logTRACE, (obj), __func__, __FILE__, __LINE__)
+
 #ifdef DEBUG
 
 #ifndef DEBUG_LVL

util.cpp

@@ -1,4 +1,5 @@
-#include<stdint.h>
+#define __STDC_LIMIT_MACROS
+#include <stdint.h>
 #include "ast.hpp"
 #include "util.hpp"
 #include "prelexer.hpp"

win/libsass.vcxproj

@@ -169,6 +169,7 @@
     <ClCompile Include="..\context.cpp" />
     <ClCompile Include="..\contextualize.cpp" />
     <ClCompile Include="..\contextualize_eval.cpp" />
+    <ClCompile Include="..\debug.cpp" />
     <ClCompile Include="..\error_handling.cpp" />
     <ClCompile Include="..\eval.cpp" />
     <ClCompile Include="..\expand.cpp" />