Move similar/2d/pcx.c -> similar/2d/pcx.cpp

SConstruct

@@ -742,7 +742,7 @@ class DXXProgram(DXXCommon):
 		'source':[os.path.join('similar', f) for f in [
 '2d/font.cpp',
 '2d/palette.cpp',
-'2d/pcx.c',
+'2d/pcx.cpp',
 '3d/interp.c',
 'arch/sdl/digi.c',
 'arch/sdl/digi_audio.c',

common/include/pcx.h

@@ -20,6 +20,10 @@ COPYRIGHT 1993-1998 PARALLAX SOFTWARE CORPORATION.  ALL RIGHTS RESERVED.
 #ifndef _PCX_H
 #define _PCX_H
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 #define PCX_ERROR_NONE          0
 #define PCX_ERROR_OPENING       1
 #define PCX_ERROR_NO_HEADER     2
@@ -46,4 +50,8 @@ extern int pcx_write_bitmap( const char * filename, grs_bitmap * bmp, ubyte * pa
 
 extern const char *pcx_errormsg(int error_number);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif