sys: change Sys_MakeCodeWritable API to take start/end addrs

All the callers had their start and end addresses anyway, so do the length
calculation in just one place. Fixes the last few WIN64 specific build
warnings as well.

Signed-off-by: Kevin Shanahan <kmshanah@disenchant.net>

common/d_modech.c

@@ -22,7 +22,7 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #include "quakedef.h"
 #include "d_local.h"
 #include "render.h"
-#include "sys.h"		/* Sys_MakeCodeWriteable() */
+#include "sys.h"
 
 int d_vrectx, d_vrecty, d_vrectright_particle, d_vrectbottom_particle;
 
@@ -40,13 +40,9 @@ void
 D_Patch(void)
 {
 #ifdef USE_X86_ASM
-
     static qboolean protectset8 = false;
-
     if (!protectset8) {
-	Sys_MakeCodeWriteable((unsigned long)D_PolysetAff8Start,
-			      (unsigned long)D_PolysetAff8End -
-			      (unsigned long)D_PolysetAff8Start);
+	Sys_MakeCodeWriteable(D_PolysetAff8Start, D_PolysetAff8End);
 	protectset8 = true;
     }
 #endif /* USE_X86_ASM */

common/r_main.c

@@ -267,8 +267,7 @@ R_Init(void)
 
 // TODO: collect 386-specific code in one place
 #ifdef USE_X86_ASM
-    Sys_MakeCodeWriteable((long)R_EdgeCodeStart,
-			  (long)R_EdgeCodeEnd - (long)R_EdgeCodeStart);
+    Sys_MakeCodeWriteable(R_EdgeCodeStart, R_EdgeCodeEnd);
 #endif
 
     D_Init();
@@ -505,13 +504,11 @@ R_ViewChanged(vrect_t *pvrect, int lineadj, float aspect)
 // TODO: collect 386-specific code in one place
 #ifdef USE_X86_ASM
     if (r_pixbytes == 1) {
-	Sys_MakeCodeWriteable((long)R_Surf8Start,
-			      (long)R_Surf8End - (long)R_Surf8Start);
+	Sys_MakeCodeWriteable(R_Surf8Start, R_Surf8End);
 	colormap = vid.colormap;
 	R_Surf8Patch();
     } else {
-	Sys_MakeCodeWriteable((long)R_Surf16Start,
-			      (long)R_Surf16End - (long)R_Surf16Start);
+	Sys_MakeCodeWriteable(R_Surf16Start, R_Surf16End);
 	colormap = vid.colormap16;
 	R_Surf16Patch();
     }

common/sys_null.c

@@ -59,7 +59,7 @@ SYSTEM IO
 */
 
 void
-Sys_MakeCodeWriteable(unsigned long startaddr, unsigned long length)
+Sys_MakeCodeWriteable(void *start_addr, void *end_addr)
 {
 }
 

common/sys_unix.c

@@ -298,19 +298,18 @@ Sys_MakeCodeWriteable
 ================
 */
 void
-Sys_MakeCodeWriteable(unsigned long startaddr, unsigned long length)
+Sys_MakeCodeWriteable(void *start_addr, void *end_addr)
 {
-    int r;
-    unsigned long addr;
-    int psize = getpagesize();
+    void *addr;
+    size_t length;
+    intptr_t pagesize;
+    int result;
 
-    addr = (startaddr & ~(psize - 1)) - psize;
-
-//      fprintf(stderr, "writable code %lx(%lx)-%lx, length=%lx\n", startaddr,
-//                      addr, startaddr+length, length);
-
-    r = mprotect((char *)addr, length + startaddr - addr + psize, 7);
-
-    if (r < 0)
+    pagesize = getpagesize();
+    addr = (void *)((intptr_t)start_addr & ~(pagesize - 1));
+    length = ((byte *)end_addr - (byte *)addr) + pagesize - 1;
+    length &= ~(pagesize - 1);
+    result = mprotect(addr, length, PROT_READ | PROT_WRITE | PROT_EXEC);
+    if (result < 0)
 	Sys_Error("Protection change failed");
 }

common/sys_win.c

@@ -891,12 +891,14 @@ Sys_MakeCodeWriteable
 ================
 */
 void
-Sys_MakeCodeWriteable(unsigned long startaddr, unsigned long length)
+Sys_MakeCodeWriteable(void *start_addr, void *end_addr)
 {
     DWORD dummy;
     BOOL success;
+    size_t length;
 
-    success = VirtualProtect((LPVOID)startaddr, length, PAGE_READWRITE, &dummy);
+    length = (byte *)end_addr - (byte *)start_addr;
+    success = VirtualProtect(start_addr, length, PAGE_READWRITE, &dummy);
     if (!success)
 	Sys_Error("Protection change failed");
 }

include/sys.h

@@ -41,8 +41,8 @@ void Sys_mkdir(const char *path);
 
 //
 // memory protection
-//
-void Sys_MakeCodeWriteable(unsigned long startaddr, unsigned long length);
+//  changes protection from start_addr, up to but not including end_addr
+void Sys_MakeCodeWriteable(void *start_addr, void *end_addr);
 
 //
 // system IO