added fetching PI to expression parser, fixed compilation warning

src/basic/basic_commands/cmd_print.s

@@ -72,6 +72,8 @@ cmd_print_float:
 	// XXX probably we should also check INTFLG here
 	// XXX provide implementation
 
+	jmp do_NOT_IMPLEMENTED_error
+
 	// FALLTROUGH
 
 cmd_print_next_arg:

src/basic/engine_runtime/ad9e.frmevl.jmp.s

@@ -0,0 +1,8 @@
+// #LAYOUT# STD *       #TAKE
+// #LAYOUT# X16 BASIC_0 #TAKE-OFFSET 2000
+// #LAYOUT# *   BASIC_0 #TAKE
+// #LAYOUT# *   *       #IGNORE
+
+// Just a compatibility jump - our routine is longer than original one
+
+	jmp FRMEVL

src/basic/engine_runtime/frmevl.s

@@ -1,5 +1,4 @@
 // #LAYOUT# STD *       #TAKE
-// #LAYOUT# X16 BASIC_0 #TAKE-OFFSET 2000
 // #LAYOUT# *   BASIC_0 #TAKE
 // #LAYOUT# *   *       #IGNORE
 
@@ -19,7 +18,7 @@
 //   in a correct order
 //
 
-// XXX finish the implementation: invoking functions, fetcching PI, fetching float, fetching variables
+// XXX finish the implementation: invoking functions, fetching floats
 
 
 FRMEVL:
@@ -78,7 +77,7 @@ FRMEVL_loop:
 	dew TXTPTR
 #endif
 	jsr fetch_variable
-	bcs !+
+	bcs FRMEVL_fetch_float
 
 	// Found the variable - copy descriptor to FAC1
 
@@ -116,17 +115,6 @@ FRMEVL_loop:
 
 	jmp_8 FRMEVL_got_value
 
-!:
-	// There is one possibility left - a floating point value
-
-
-	// XXX implement this part
-
-
-	// Nothing recognized
-
-	jmp do_SYNTAX_error
-
 //
 // This subroutine handles the situation when we have to execute a BASIC function
 // in place when parser normally expects a value
@@ -175,9 +163,11 @@ FRMEVL_handle_bracket:
 
 FRMEVL_fetch_PI:
 
-	// XXX implement this
+	lda #<const_PI
+	ldy #>const_PI
+	jsr mov_MEM_FAC1
 
-	jmp do_NOT_IMPLEMENTED_error
+	jmp_8 FRMEVL_got_value_float
 
 //
 // This subroutine fetches the floating point value from the 'outside world'
@@ -189,6 +179,14 @@ FRMEVL_fetch_float:
 
 	jmp do_NOT_IMPLEMENTED_error
 
+	// FALLTROUGH
+
+FRMEVL_got_value_float:
+
+	lda #$00
+	sta VALTYP
+	beq FRMEVL_got_value
+
 //
 // This subroutine fetches the string value from the 'outside world'
 //

tools/pngprepare.c

@@ -108,13 +108,16 @@ void abort_(const char * s, ...)
 void read_png_file(char* file_name)
 {
   unsigned char header[8];    // 8 is the maximum size that can be checked
+  size_t readResult;
 
   /* open file and test for it being a png */
   infile = fopen(file_name, "rb");
   if (infile == NULL)
     abort_("[read_png_file] File %s could not be opened for reading", file_name);
 
-  fread(header, 1, 8, infile);
+  readResult = fread(header, 1, 8, infile);
+  if (readResult != 8)
+    abort_("[read_png_file] File %s could not be read", file_name);
   if (png_sig_cmp(header, 0, 8))
     abort_("[read_png_file] File %s is not recognized as a PNG file", file_name);