From 6f433ff58ff264a608436a1bc4c8a3ef2f4995b5 Mon Sep 17 00:00:00 2001
From: Timothy Collett <tcollett+github@topazgryphon.org>
Date: Fri, 29 Jun 2012 10:15:48 -0400
Subject: [PATCH] Move back to using interposition to be more portable

---
 library/Hooks-darwin.cpp | 26 +++++++++++++++++---------
 library/include/Core.h   |  7 +++++++
 library/include/Hooks.h  |  6 ++++++
 3 files changed, 30 insertions(+), 9 deletions(-)

diff --git a/library/Hooks-darwin.cpp b/library/Hooks-darwin.cpp
index ef89105d4..190616b86 100644
--- a/library/Hooks-darwin.cpp
+++ b/library/Hooks-darwin.cpp
@@ -38,11 +38,11 @@ distribution.
 #include <string>
 #include <map>
 
-/*typedef struct interpose_s
+typedef struct interpose_s
 {
   void *new_func;
   void *orig_func;
-} interpose_t;*/
+} interpose_t;
 
 #include "DFHack.h"
 #include "Core.h"
@@ -58,11 +58,18 @@ distribution.
      
 };*/
 
+#define DYLD_INTERPOSE(_replacment,_replacee) __attribute__((used)) static struct{ const void* replacment; const void* replacee; } _interpose_##_replacee __attribute__ ((section ("__DATA,__interpose"))) = { (const void*)(unsigned long)&_replacment, (const void*)(unsigned long)&_replacee }; 
+
+DYLD_INTERPOSE(DFH_SDL_Init,SDL_Init);
+DYLD_INTERPOSE(DFH_SDL_PollEvent,SDL_PollEvent);
+DYLD_INTERPOSE(DFH_SDL_Quit,SDL_Quit);
+DYLD_INTERPOSE(DFH_SDL_NumJoysticks,SDL_NumJoysticks);
+
 /*******************************************************************************
 *                           SDL part starts here                               *
 *******************************************************************************/
 // hook - called for each game tick (or more often)
-DFhackCExport int SDL_NumJoysticks(void)
+DFhackCExport int DFH_SDL_NumJoysticks(void)
 {
     DFHack::Core & c = DFHack::Core::getInstance();
     return c.Update();
@@ -70,7 +77,7 @@ DFhackCExport int SDL_NumJoysticks(void)
 
 // hook - called at program exit
 static void (*_SDL_Quit)(void) = 0;
-DFhackCExport void SDL_Quit(void)
+DFhackCExport void DFH_SDL_Quit(void)
 {
     DFHack::Core & c = DFHack::Core::getInstance();
     c.Shutdown();
@@ -79,16 +86,16 @@ DFhackCExport void SDL_Quit(void)
         _SDL_Quit();
     }*/
     
-    _SDL_Quit();
+    SDL_Quit();
 }
 
 // called by DF to check input events
 static int (*_SDL_PollEvent)(SDL::Event* event) = 0;
-DFhackCExport int SDL_PollEvent(SDL::Event* event)
+DFhackCExport int DFH_SDL_PollEvent(SDL::Event* event)
 {
     pollevent_again:
     // if SDL returns 0 here, it means there are no more events. return 0
-    int orig_return = _SDL_PollEvent(event);
+    int orig_return = SDL_PollEvent(event);
     if(!orig_return)
         return 0;
     // otherwise we have an event to filter
@@ -128,7 +135,7 @@ DFhackCExport int wgetch(WINDOW *win)
 
 // hook - called at program start, initialize some stuffs we'll use later
 static int (*_SDL_Init)(uint32_t flags) = 0;
-DFhackCExport int SDL_Init(uint32_t flags)
+DFhackCExport int DFH_SDL_Init(uint32_t flags)
 {
     // reroute stderr
     fprintf(stderr,"dfhack: attempting to hook in\n");
@@ -158,6 +165,7 @@ DFhackCExport int SDL_Init(uint32_t flags)
     DFHack::Core & c = DFHack::Core::getInstance();
     //c.Init();
     
-    int ret = _SDL_Init(flags);
+    //int ret = _SDL_Init(flags);
+    int ret = SDL_Init(flags);
     return ret;
 }
\ No newline at end of file
diff --git a/library/include/Core.h b/library/include/Core.h
index e4d1080d6..653298d8f 100644
--- a/library/include/Core.h
+++ b/library/include/Core.h
@@ -83,10 +83,17 @@ namespace DFHack
     // Better than tracking some weird variables all over the place.
     class DFHACK_EXPORT Core
     {
+#ifdef _DARWIN
+        friend int  ::DFH_SDL_NumJoysticks(void);
+        friend void ::DFH_SDL_Quit(void);
+        friend int  ::DFH_SDL_PollEvent(SDL::Event *);
+        friend int  ::DFH_SDL_Init(uint32_t flags);
+#else
         friend int  ::SDL_NumJoysticks(void);
         friend void ::SDL_Quit(void);
         friend int  ::SDL_PollEvent(SDL::Event *);
         friend int  ::SDL_Init(uint32_t flags);
+#endif
         friend int  ::wgetch(WINDOW * w);
         friend int  ::egg_init(void);
         friend int  ::egg_shutdown(void);
diff --git a/library/include/Hooks.h b/library/include/Hooks.h
index 418a5ce3b..325af43eb 100644
--- a/library/include/Hooks.h
+++ b/library/include/Hooks.h
@@ -44,6 +44,12 @@ namespace SDL
 
 // these functions are here because they call into DFHack::Core and therefore need to
 // be declared as friend functions/known
+#ifdef _DARWIN
+DFhackCExport int DFH_SDL_NumJoysticks(void);
+DFhackCExport void DFH_SDL_Quit(void);
+DFhackCExport int DFH_SDL_PollEvent(SDL::Event* event);
+DFhackCExport int DFH_SDL_Init(uint32_t flags);
+#endif
 DFhackCExport int SDL_NumJoysticks(void);
 DFhackCExport void SDL_Quit(void);
 DFhackCExport int SDL_PollEvent(SDL::Event* event);