One more example: a System Extension (INIT)

CMakeLists.txt

@@ -31,6 +31,7 @@ add_subdirectory(Samples/HelloWorld)
 add_subdirectory(Samples/Raytracer)
 add_subdirectory(Samples/Launcher)
 add_subdirectory(Samples/Dialog)
+add_subdirectory(Samples/SystemExtension)
 else()
 
 configure_file(cmake/retro68.toolchain.cmake.in cmake/retro68.toolchain.cmake @ONLY)

Samples/SystemExtension/CMakeLists.txt

@@ -0,0 +1,16 @@
+add_executable(SystemExtension
+	SystemExtension.c
+	SystemExtension.r
+	ShowInitIcon.c
+	ShowInitIcon.h)
+
+set_target_properties(SystemExtension PROPERTIES OUTPUT_NAME SystemExtension.flt)
+
+add_custom_command(
+	OUTPUT SystemExtension.dsk
+	COMMAND ${REZ} ${CMAKE_CURRENT_SOURCE_DIR}/SystemExtension.r
+					--copy ${CMAKE_CURRENT_SOURCE_DIR}/Icons.rsrc.bin
+					-o SystemExtension.dsk
+					-t INIT
+	DEPENDS SystemExtension SystemExtension.r Icons.rsrc.bin)
+add_custom_target(SystemExtension_INIT ALL DEPENDS SystemExtension.dsk)

Samples/SystemExtension/ShowInitIcon.c

@@ -0,0 +1,161 @@
+// ShowInitIcon - version 1.0.1, May 30th, 1995
+// This code is intended to let INIT writers easily display an icon at startup time.
+// View in Geneva 9pt, 4-space tabs
+
+// Written by: Peter N Lewis <peter@mail.peter.com.au>, Jim Walker <JWWalker@aol.com>
+// and François Pottier <pottier@dmi.ens.fr>, with thanks to previous ShowINIT authors.
+// Send comments and bug reports to François Pottier.
+
+// This version features:
+// - Short and readable code.
+// - Correctly wraps around when more than one row of icons has been displayed.
+// - works with System 6
+// - Built with Universal Headers & CodeWarrior. Should work with other headers/compilers.
+
+#include <Memory.h>
+#include <Resources.h>
+#include <Icons.h>
+#include <OSUtils.h>
+#include "ShowInitIcon.h"
+
+// You should set SystemSixOrLater in your headers to avoid including glue for SysEnvirons.
+
+// ---------------------------------------------------------------------------------------------------------------------
+// Set this flag to 1 if you want to compile this file into a stand-alone resource (see note below).
+// Set it to 0 if you want to include this source file into your INIT project.
+
+#if 0
+#define ShowInitIcon main
+#endif
+
+// ---------------------------------------------------------------------------------------------------------------------
+// The ShowINIT mechanism works by having each INIT read/write data from these globals.
+// The MPW C compiler doesn't accept variables declared at an absolute address, so I use these macros instead.
+// Only one macro is defined per variable; there is no need to define a Set and a Get accessor like in <LowMem.h>.
+
+#define	LMVCheckSum		(* (unsigned short*) 0x928)
+#define	LMVCoord		(* (         short*) 0x92A)
+#define	LMHCoord		(* (         short*) 0x92C)
+#define	LMHCheckSum		(* (unsigned short*) 0x92E)
+
+// ---------------------------------------------------------------------------------------------------------------------
+// Prototypes for the subroutines. The main routine comes first; this is necessary to make THINK C's "Custom Header" option work.
+
+static unsigned short CheckSum (short x);
+static void ComputeIconRect (Rect* iconRect, Rect* screenBounds);
+static void AdvanceIconPosition (Rect* iconRect);
+static void DrawBWIcon (short iconID, Rect *iconRect);
+
+// ---------------------------------------------------------------------------------------------------------------------
+// Main routine.
+
+typedef struct {
+	QDGlobals			qd;									// Storage for the QuickDraw globals
+	long				qdGlobalsPtr;							// A5 points to this place; it will contain a pointer to qd
+} QDStorage;
+
+pascal void ShowInitIcon (short iconFamilyID, Boolean advance)
+{
+	long				oldA5;								// Original value of register A5
+	QDStorage			qds;									// Fake QD globals
+	CGrafPort			colorPort;
+	GrafPort			bwPort;
+	Rect				destRect;
+	SysEnvRec		environment;							// Machine configuration.
+	
+	oldA5 = SetA5((long) &qds.qdGlobalsPtr);						// Tell A5 to point to the end of the fake QD Globals
+	InitGraf(&qds.qd.thePort);								// Initialize the fake QD Globals
+	
+	SysEnvirons(curSysEnvVers, &environment);					// Find out what kind of machine this is
+
+	ComputeIconRect(&destRect, &qds.qd.screenBits.bounds);			// Compute where the icon should be drawn
+
+	if (environment.systemVersion >= 0x0700 && environment.hasColorQD) {
+		OpenCPort(&colorPort);
+		PlotIconID(&destRect, atNone, ttNone, iconFamilyID);
+		CloseCPort(&colorPort);
+	}
+	else {
+		OpenPort(&bwPort);
+		DrawBWIcon(iconFamilyID, &destRect);
+		ClosePort(&bwPort);
+	}
+	
+	if (advance)
+		AdvanceIconPosition (&destRect);
+		
+	SetA5(oldA5); 											// Restore A5 to its previous value
+}
+
+// ---------------------------------------------------------------------------------------------------------------------
+// A checksum is used to make sure that the data in there was left by another ShowINIT-aware INIT.
+
+static unsigned short CheckSum (short x)
+{
+	return (unsigned short)(((x << 1) | (x >> 15)) ^ 0x1021);
+}
+
+// ---------------------------------------------------------------------------------------------------------------------
+// ComputeIconRect computes where the icon should be displayed.
+
+static void ComputeIconRect (Rect* iconRect, Rect* screenBounds)
+{
+	if (CheckSum(LMHCoord) != LMHCheckSum)					// If we are first, we need to initialize the shared data.
+		LMHCoord = 8;
+	if (CheckSum(LMVCoord) != LMVCheckSum)
+		LMVCoord = (short)(screenBounds->bottom - 40);
+	
+	if (LMHCoord + 34 > screenBounds->right) {					// Check whether we must wrap
+		iconRect->left = 8;
+		iconRect->top = (short)(LMVCoord - 40);
+	}
+	else {
+		iconRect->left = LMHCoord;
+		iconRect->top = LMVCoord;
+	}
+	iconRect->right  = (short)(iconRect->left + 32);
+	iconRect->bottom = (short)(iconRect->top  + 32);
+}
+
+// AdvanceIconPosition updates the shared global variables so that the next extension will draw its icon beside ours.
+
+static void AdvanceIconPosition (Rect* iconRect)
+{
+	LMHCoord = (short)(iconRect->left + 40);					// Update the shared data
+	LMVCoord = iconRect->top;
+	LMHCheckSum = CheckSum(LMHCoord);
+	LMVCheckSum = CheckSum(LMVCoord);
+}
+
+// DrawBWIcon draws the 'ICN#' member of the icon family. It works under System 6.
+
+static void DrawBWIcon (short iconID, Rect *iconRect)
+{
+	Handle		icon;
+	BitMap		source, destination;
+	GrafPtr		port;
+	
+	icon = Get1Resource('ICN#', iconID);
+	if (icon != NULL) {
+		HLock(icon);
+														// Prepare the source and destination bitmaps.
+		source.baseAddr = *icon + 128;						// Mask address.
+		source.rowBytes = 4;
+		SetRect(&source.bounds, 0, 0, 32, 32);
+		GetPort(&port);
+		destination = port->portBits;
+														// Transfer the mask.
+		CopyBits(&source, &destination, &source.bounds, iconRect, srcBic, nil);
+														// Then the icon.
+		source.baseAddr = *icon;
+		CopyBits(&source, &destination, &source.bounds, iconRect, srcOr, nil);
+	}
+}
+
+// ---------------------------------------------------------------------------------------------------------------------
+// Notes
+
+// Checking for PlotIconID:
+// We (PNL) now check for system 7 and colour QD, and use colour graf ports and PlotIconID only if both are true
+// Otherwise we use B&W grafport and draw using PlotBWIcon.
+

Samples/SystemExtension/ShowInitIcon.h

@@ -0,0 +1,21 @@
+#ifndef __ShowInitIcon__
+#define __ShowInitIcon__
+
+#include <Types.h>
+
+// Usage: pass the ID of your icon family (ICN#/icl4/icl8) to have it drawn in the right spot.
+// If 'advance' is true, the next INIT icon will be drawn to the right of your icon. If it is false, the next INIT icon will overwrite
+// yours. You can use it to create animation effects by calling ShowInitIcon several times with 'advance' set to false.
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+pascal void ShowInitIcon (short iconFamilyID, Boolean advance);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* __ShowInitIcon__ */
+

Samples/SystemExtension/SystemExtension.c

@@ -0,0 +1,16 @@
+#include <OSUtils.h>
+#include "ShowInitIcon.h"
+#include "Retro68Runtime.h"
+
+void _start()
+{
+	RETRO68_RELOCATE();
+	Retro68CallConstructors();
+
+	ShowInitIcon(130, false);
+	Delay(20, NULL);
+	ShowInitIcon(128, true);
+	Delay(40, NULL);
+
+	Retro68FreeGlobals();
+}

Samples/SystemExtension/SystemExtension.r

@@ -0,0 +1,13 @@
+type 'INIT' (0) {
+	hex string dontBreakAtEntry = $"", breakAtEntry = $"A9FF";
+	longint = 0x61000002;	// bsr *+2
+	integer = 0x0697; // addi.l #_, (a7)
+	longint = $$long(fltfile + 8*8) + 8;
+	integer = 0x4e75; // rts
+fltfile:
+	hex string;
+};
+
+resource 'INIT' (0) {
+	dontBreakAtEntry, $$read("SystemExtension.flt");
+};

libretro/CMakeLists.txt

@@ -33,4 +33,4 @@ add_library(retrocrt
 	consolehooks.c)
 
 install(TARGETS retrocrt  DESTINATION lib)
-
+install(FILES Retro68Runtime.h DESTINATION include)

libretro/Retro68Runtime.h

@@ -42,5 +42,6 @@
 
 void Retro68Relocate();
 void Retro68CallConstructors();
+void Retro68FreeGlobals();
 
 #define RETRO68_RELOCATE() RETRO68_CALL_UNRELOCATED(Retro68Relocate,())

libretro/relocate.c

@@ -66,7 +66,7 @@ extern void __fini_section_end(void);
 
 
 static long headerVirtualAddress = -0x40;
-static Ptr savedBSS = (Ptr) -1;
+static Ptr bssPtr = (Ptr) -1;
 
 #define ACCESS_DISPLACED(VAR) \
 	( * (typeof(&VAR)) ((char*)(&VAR) + displacement) )
@@ -92,10 +92,14 @@ void Retro68Relocate()
 	long data_end = header->data_end - 0x40;
 	long bss_displacement = 0;
 
-	Ptr bss = ACCESS_DISPLACED(savedBSS);
+	Ptr bss = ACCESS_DISPLACED(bssPtr);
 	if(bss == (Ptr)-1)
 	{
-		bss = NewPtrClear(bss_size);
+		THz zone = ApplicationZone();
+		if(!zone || (char*)header < (char*)zone)
+			bss = NewPtrSysClear(bss_size);
+		else
+			bss = NewPtrClear(bss_size);
 		bss_displacement = (long)bss - data_end;
 	}
 
@@ -121,7 +125,7 @@ void Retro68Relocate()
 	// accessing globals and calling functions is OK below here.
 
 	headerVirtualAddress += displacement;
-	savedBSS = bss;
+	bssPtr = bss;
 }
 
 void Retro68CallConstructors()
@@ -135,3 +139,13 @@ void Retro68CallConstructors()
 		p += 6;
 	}
 }
+
+void Retro68FreeGlobals()
+{
+	if(bssPtr != (Ptr) -1)
+	{
+		DisposePtr(bssPtr);
+		bssPtr = (Ptr) -1;
+	}
+}
+

libretro/start.c

@@ -25,7 +25,6 @@
 
 #include <stdint.h>
 #include <stdlib.h>
-#include <SegLoad.h>
 
 #include "Retro68Runtime.h"