diff --git a/source/aux_textfile.cpp b/source/aux_textfile.cpp
index 1db7cf5..cb17782 100644
--- a/source/aux_textfile.cpp
+++ b/source/aux_textfile.cpp
@@ -9,9 +9,20 @@ namespace textfile
     int fsize = 0;
     int p = 0;
 
+    const int toInt(std::string token)
+    {
+        int value = 0;
+        for (std::size_t i=0; i<token.length(); ++i)
+        {
+            if (token[i]<48 || token[i]>57) return 0;
+            value = (value*10) + (token[i]-48);
+        }
+        return value;
+    }
+
     const bool open(std::string filename)
     {
-        buffer = file::getFileBuffer(filename.c_str());
+        buffer = file::getFileBuffer(filename.c_str(), &fsize);
         p = 0;
 
         return true;
@@ -52,6 +63,6 @@ namespace textfile
 
     const int getIntValue(std::string token)
     {
-        return std::stoi(getStringValue(token));
+        return toInt(getStringValue(token));
     }
 }
diff --git a/source/aux_textfile.h b/source/aux_textfile.h
index f0d2ff4..a5178b2 100644
--- a/source/aux_textfile.h
+++ b/source/aux_textfile.h
@@ -4,6 +4,8 @@
 
 namespace textfile
 {
+    const int toInt(std::string token);
+    
     const bool open(std::string filename);
 
     void close();
diff --git a/source/proc_mapa.cpp b/source/proc_mapa.cpp
index 6dcd965..48b96a8 100644
--- a/source/proc_mapa.cpp
+++ b/source/proc_mapa.cpp
@@ -42,7 +42,7 @@ namespace mapa
 
 		do {
 			textfile::searchToken("LEVEL");
-		} while (std::stoi(textfile::getNextToken()) != game::getConfig("fase"));
+		} while (textfile::toInt(textfile::getNextToken()) != game::getConfig("fase"));
 
 		const int tileset = textfile::getIntValue("tileset");
 		arounders::orientacio_inicial = textfile::getIntValue("orientacio");
@@ -58,10 +58,10 @@ namespace mapa
 		accions::corda = textfile::getIntValue("corda");
 
 		ini_x = textfile::getIntValue("inici");
-		ini_y = std::stoi(textfile::getNextToken());
+		ini_y = textfile::toInt(textfile::getNextToken());
 
 		fin_x = textfile::getIntValue("final");
-		fin_y = std::stoi(textfile::getNextToken());
+		fin_y = textfile::toInt(textfile::getNextToken());
 
 		//int tilemap[200];
 		//for (int y=0; y<10; ++y) for (int x=0; x<10; ++x) fscanf(f, "%i", &tilemap[x+y*20]);
@@ -76,13 +76,13 @@ namespace mapa
 		for (int y=0; y<10; ++y)
 			for (int x=0; x<10; ++x)
 			{
-				int tile; fscanf(f, "%i", &tile);
+				int tile = textfile::toInt(textfile::getNextToken());
 				if (tile > 0) draw::draw(x*16, y*16, 16, 16, (tile-1)*16, tileset*16);
 			}
 
 		draw::freeSurface(tiles);
 
-		textfile::fclose();
+		textfile::close();
 
 		draw::surface *marcador = draw::loadSurface("marcador.gif");
 		draw::setSource(marcador);