A tiny amount of work toward an x86 backtrace facility.

stepmania/src/archutils/Darwin/arch_setup.h

@@ -34,14 +34,17 @@ typedef unsigned long long UInt64;
  * even though they resolve to the same thing (bug in gcc?). */
 #define HAVE_MACHINE_ENDIAN_H
 
-// Looking ahead to "Universal binaries."
+#if defined(__ppc__)
-#ifdef __ppc__
+# define CPU_PPC
 # define ENDIAN_BIG
 # define BACKTRACE_LOOKUP_METHOD_DARWIN_DYLD
 # define BACKTRACE_METHOD_POWERPC_DARWIN
 # define CRASH_HANDLER
-#else
+#elif defined(__i386__)
+# define CPU_X86
 # define ENDIAN_LITTLE
+# define BACKTRACE_METHOD_X86_DARWIN
+# define BACKTRACE_LOOKUP_METHOD_DLADDR
 #endif
 
 #ifndef MACOSX
@@ -197,7 +200,7 @@ namespace std
 #endif
 
 /*
- * (c) 2003-2005 Steve Checkoway
+ * (c) 2003-2006 Steve Checkoway
  * All rights reserved.
  * 
  * Permission is hereby granted, free of charge, to any person obtaining a

stepmania/src/archutils/Unix/Backtrace.cpp

@@ -404,6 +404,22 @@ void GetBacktrace( const void **buf, size_t size, const BacktraceContext *ctx )
 
 	do_backtrace( buf, size, ctx );
 }
+#elif defined(BACKTRACE_METHOD_X86_DARWIN)
+void InitializeBacktrace() { }
+
+void GetSignalBacktraceContext( BacktraceContext *ctx, const ucontext_t *uc )
+{
+	ctx->ip = (void *) uc->uc_mcontext->ss.eip;
+	ctx->bp = (void *) uc->uc_mcontext->ss.ebp;
+	ctx->sp = (void *) uc->uc_mcontext->ss.esp;
+}
+
+void GetBacktrace( const void **buf, size_t size, const BacktraceContext *ctx )
+{
+	buf[0] = BACKTRACE_METHOD_NOT_AVAILABLE;
+	buf[1] = NULL;
+}
+
 #elif defined(BACKTRACE_METHOD_POWERPC_DARWIN)
 typedef struct Frame
 {

stepmania/src/archutils/Unix/Backtrace.h

@@ -14,7 +14,7 @@ struct BacktraceContext
 	pid_t pid;
 #endif
 
-#if defined(MACOSX)
+#if defined(CPU_PPC)
 	void *FramePtr, *PC;
 #endif
 };