Replace tprintf_internal by tprintf and clean tprintf code

Commit 4d514d5 introduced tprintf_internal
with an additional argument "level" which was removed again in commit
7dc5296.

So we can now restore the original state without tprintf_internal.

Remove also the declaration of debug_window_on (it does not exist since
commit 030aae9) and make the
configuration parameter debug_file local as it is only used by tprintf.

Signed-off-by: Stefan Weil <sw@weilnetz.de>

src/ccutil/tprintf.cpp

@@ -22,23 +22,20 @@
 #include "config_auto.h"
 #endif
 
-#include          <stdio.h>
-#include          <stdarg.h>
-#include          "ccutil.h"
-#include          "params.h"
-#include          "strngs.h"
-#include          "tprintf.h"
+#include <cstdio>
+#include <cstdarg>
+#include "ccutil.h"
+#include "params.h"
+#include "strngs.h"
+#include "tprintf.h"
 
 #define MAX_MSG_LEN     65536
 
-#define EXTERN
-// Since tprintf is protected by a mutex, these parameters can remain global.
-DLLSYM STRING_VAR(debug_file, "", "File to send tprintf output to");
+static STRING_VAR(debug_file, "", "File to send tprintf output to");
 
-DLLSYM void
-tprintf_internal(                       // Trace printf
-    const char *format, ...             // Message
-) {
+// Trace printf
+DLLSYM void tprintf(const char *format, ...)
+{
   tesseract::tprintfMutex.Lock();
   va_list args;                  // variable args
   static FILE *debugfp = nullptr;   // debug file

src/ccutil/tprintf.h

@@ -17,20 +17,13 @@
  *
  **********************************************************************/
 
-#ifndef           TESSERACT_CCUTIL_TPRINTF_H
-#define           TESSERACT_CCUTIL_TPRINTF_H
+#ifndef TESSERACT_CCUTIL_TPRINTF_H
+#define TESSERACT_CCUTIL_TPRINTF_H
 
-#include "params.h"
-
-extern DLLSYM STRING_VAR_H(debug_file, "",
-                           "File to send tprintf output to");
-extern DLLSYM BOOL_VAR_H(debug_window_on, TRUE,
-                         "Send tprintf to window unless file set");
+#include "platform.h"   // for TESS_API
 
 // Main logging function.
-#define tprintf(...) tprintf_internal(__VA_ARGS__)
-
-extern TESS_API void tprintf_internal(  // Trace printf
-    const char *format, ...);           // Message
+extern TESS_API void tprintf(  // Trace printf
+    const char *format, ...);  // Message
 
 #endif  // define TESSERACT_CCUTIL_TPRINTF_H

src/training/tlog.h

@@ -32,7 +32,7 @@ DECLARE_INT_PARAM_FLAG(tlog_level);
 // config file like other params.
 #define tlog(level, ...) {                        \
   if (FLAGS_tlog_level >= level) {                \
-    tprintf_internal(__VA_ARGS__);                \
+    tprintf(__VA_ARGS__);                         \
   }                                               \
 }