improve GetTickCount64 patching

scripts/patch_xp.c

@@ -0,0 +1,54 @@
+// patch GetTickCount64 for running on Windows XP
+#include <stdio.h>
+
+int main(int argc, char** argv) {
+  unsigned char* buf;
+  FILE* f=fopen(argv[1],"rb");
+  if (f==NULL) {
+    perror("open");
+    return 1;
+  }
+
+  fseek(f,0,SEEK_END);
+
+  size_t size=ftell(f);
+  buf=malloc(size);
+
+  fseek(f,0,SEEK_SET);
+
+  fread(buf,1,size,f);
+  fclose(f);
+
+  // patch
+  size_t remain=size;
+  unsigned char* buf1=buf;
+  while (size>=14) {
+    unsigned char* where=memchr(buf1,'G',remain);
+    if (where==NULL) {
+      printf("GetTickCount64 not found\n");
+      break;
+    }
+
+    if (memcmp(where,"GetTickCount64",14)==0) {
+      printf("found GetTickCount64 - patching...\n");
+      where[12]=0;
+      where[13]=0;
+      break;
+    }
+
+    buf1=where+1;
+    remain=size-(buf1-buf);
+  }
+
+  // write
+  FILE* of=fopen(argv[1],"wb");
+  if (f==NULL) {
+    perror("open write");
+    return 1;
+  }
+
+  fwrite(buf,1,size,of);
+  fclose(of);
+
+  return 0;
+}

scripts/release-winxp.sh

@@ -36,9 +36,8 @@ cp ../../res/docpdf/manual.pdf . || exit 1
 i686-w64-mingw32-strip -s furnace.exe || exit 1
 
 # patch to remove GetTickCount64
-xxd -c 256 -ps furnace.exe | sed "s/4765745469636b436f756e743634/4765745469636b436f756e740000/g" | xxd -ps -r > furnace-patched.exe
-rm furnace.exe
-mv furnace-patched.exe furnace.exe
+gcc -o patch_xp ../../scripts/patch_xp.c || exit 1
+./patch_xp furnace.exe || exit 1
 
 zip -r furnace.zip LICENSE.txt furnace.exe README.txt manual.pdf papers demos instruments wavetables