Replace STRING arguments for LoadDataFromFile and SaveDataToFile

This is a step to eliminate the proprietary STRING data type
from the public Tesseract API.

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

src/ccstruct/boxread.cpp

@@ -56,7 +56,7 @@ bool ReadAllBoxes(int target_page, bool skip_blanks, const STRING& filename,
                   GenericVector<STRING>* box_texts,
                   GenericVector<int>* pages) {
   GenericVector<char> box_data;
-  if (!tesseract::LoadDataFromFile(BoxFileName(filename), &box_data))
+  if (!tesseract::LoadDataFromFile(BoxFileName(filename).c_str(), &box_data))
     return false;
   // Convert the array of bytes to a string, so it can be used by the parser.
   box_data.push_back('\0');

src/ccutil/genericvector.h

@@ -361,16 +361,11 @@ inline bool LoadDataFromFile(const char* filename, GenericVector<char>* data) {
   return result;
 }
 
-inline bool LoadDataFromFile(const STRING& filename,
-                             GenericVector<char>* data) {
-  return LoadDataFromFile(filename.string(), data);
-}
-
 // The default FileWriter writes the vector of char to the filename file,
 // returning false on error.
 inline bool SaveDataToFile(const GenericVector<char>& data,
-                           const STRING& filename) {
+                           const char* filename) {
-  FILE* fp = fopen(filename.string(), "wb");
+  FILE* fp = fopen(filename, "wb");
   if (fp == nullptr) {
     return false;
   }
@@ -380,10 +375,10 @@ inline bool SaveDataToFile(const GenericVector<char>& data,
   return result;
 }
 // Reads a file as a vector of STRING.
-inline bool LoadFileLinesToStrings(const STRING& filename,
+inline bool LoadFileLinesToStrings(const char* filename,
                                    GenericVector<STRING>* lines) {
   GenericVector<char> data;
-  if (!LoadDataFromFile(filename.string(), &data)) {
+  if (!LoadDataFromFile(filename, &data)) {
     return false;
   }
   STRING lines_str(&data[0], data.size());

src/ccutil/serialis.cpp

@@ -2,7 +2,6 @@
  * File:        serialis.cpp  (Formerly serialmac.h)
  * Description: Inline routines and macros for serialisation functions
  * Author:      Phil Cheatle
- * Created:     Tue Oct 08 08:33:12 BST 1991
  *
  * (C) Copyright 1990, Hewlett-Packard Ltd.
  ** Licensed under the Apache License, Version 2.0 (the "License");
@@ -202,9 +201,9 @@ bool TFile::Open(const STRING& filename, FileReader reader) {
   is_writing_ = false;
   swap_ = false;
   if (reader == nullptr)
-    return LoadDataFromFile(filename, data_);
+    return LoadDataFromFile(filename.c_str(), data_);
   else
-    return (*reader)(filename, data_);
+    return (*reader)(filename.c_str(), data_);
 }
 
 bool TFile::Open(const char* data, int size) {
@@ -310,9 +309,9 @@ void TFile::OpenWrite(GenericVector<char>* data) {
 bool TFile::CloseWrite(const STRING& filename, FileWriter writer) {
   ASSERT_HOST(is_writing_);
   if (writer == nullptr)
-    return SaveDataToFile(*data_, filename);
+    return SaveDataToFile(*data_, filename.c_str());
   else
-    return (*writer)(*data_, filename);
+    return (*writer)(*data_, filename.c_str());
 }
 
 int TFile::FWrite(const void* buffer, size_t size, int count) {

src/ccutil/serialis.h

@@ -46,10 +46,10 @@ constexpr size_t countof(T const (&)[N]) noexcept {
 
 // Function to read a GenericVector<char> from a whole file.
 // Returns false on failure.
-using FileReader = bool (*)(const STRING&, GenericVector<char>*);
+using FileReader = bool (*)(const char* filename, GenericVector<char>* data);
 // Function to write a GenericVector<char> to a whole file.
 // Returns false on failure.
-using FileWriter = bool (*)(const GenericVector<char>&, const STRING&);
+using FileWriter = bool (*)(const GenericVector<char>& data, const char* filename);
 
 // Deserialize data from file.
 bool DeSerialize(FILE* fp, char* data, size_t n = 1);

src/ccutil/tessdatamanager.cpp

@@ -157,9 +157,9 @@ bool TessdataManager::SaveFile(const STRING &filename,
   GenericVector<char> data;
   Serialize(&data);
   if (writer == nullptr)
-    return SaveDataToFile(data, filename);
+    return SaveDataToFile(data, filename.c_str());
   else
-    return (*writer)(data, filename);
+    return (*writer)(data, filename.c_str());
 }
 
 // Serializes to the given vector.
@@ -253,7 +253,7 @@ bool TessdataManager::CombineDataFiles(
     FILE *fp = fopen(filename.string(), "rb");
     if (fp != nullptr) {
       fclose(fp);
-      if (!LoadDataFromFile(filename, &entries_[type])) {
+      if (!LoadDataFromFile(filename.c_str(), &entries_[type])) {
         tprintf("Load of file %s failed!\n", filename.string());
         return false;
       }

src/training/lstmtester.cpp

@@ -29,7 +29,7 @@ LSTMTester::LSTMTester(int64_t max_memory)
 // loaded. The arg is a filename of a file that lists the filenames.
 bool LSTMTester::LoadAllEvalData(const STRING& filenames_file) {
   GenericVector<STRING> filenames;
-  if (!LoadFileLinesToStrings(filenames_file, &filenames)) {
+  if (!LoadFileLinesToStrings(filenames_file.c_str(), &filenames)) {
     tprintf("Failed to load list of eval filenames from %s\n",
             filenames_file.string());
     return false;

src/training/lstmtrainer.cpp

@@ -320,7 +320,7 @@ bool LSTMTrainer::MaintainCheckpoints(TestCallback tester, STRING* log_msg) {
     SaveTrainingDump(NO_BEST_TRAINER, this, &best_trainer_);
     if (error_rate < error_rate_of_last_saved_best_ * kBestCheckpointFraction) {
       STRING best_model_name = DumpFilename();
-      if (!SaveDataToFile(best_trainer_, best_model_name)) {
+      if (!SaveDataToFile(best_trainer_, best_model_name.c_str())) {
         *log_msg += " failed to write best model:";
       } else {
         *log_msg += " wrote best model:";
@@ -358,7 +358,7 @@ bool LSTMTrainer::MaintainCheckpoints(TestCallback tester, STRING* log_msg) {
     // Write a current checkpoint.
     GenericVector<char> checkpoint;
     if (!SaveTrainingDump(FULL, this, &checkpoint) ||
-        !SaveDataToFile(checkpoint, checkpoint_name_)) {
+        !SaveDataToFile(checkpoint, checkpoint_name_.c_str())) {
       *log_msg += " failed to write checkpoint.";
     } else {
       *log_msg += " wrote checkpoint.";