diff --git a/kpack_c.c b/kpack_c.c
index e9a526f..5f53670 100644
--- a/kpack_c.c
+++ b/kpack_c.c
@@ -52,8 +52,7 @@ unsigned preprocess_calltrick(unsigned char *infile, unsigned insize, unsigned c
 
     unsigned char *infile_ptr = infile;
     unsigned count = insize;
-    unsigned edx = 0;
-    unsigned char *ebx = buf;
+    unsigned char *buf_ptr = buf;
     do {
         unsigned al = *infile_ptr++;
         al -= 0x0E8;
@@ -67,21 +66,20 @@ unsigned preprocess_calltrick(unsigned char *infile, unsigned insize, unsigned c
         memcpy(&num, infile_ptr, 4);
         infile_ptr += 4;
         num += (infile_ptr - infile);
-        if (num >= insize || num >= 0x1000000) {
+        if (num >= insize || num >= 0x1000000) { // xxx:
             infile_ptr -= 4;
             ct1[*infile_ptr] = 1;
         } else {
             count -= 4;
             num = byteswap(num);
             memcpy(infile_ptr - 4, &num, 4);
-            edx++;
-            memcpy(ebx, &infile_ptr, 4);
-            ebx += 8;
+            (*ctn)++;
+            memcpy(buf_ptr, &infile_ptr, 4);
+            buf_ptr += 8;
         }
         
-    } while(count > 0);
+    } while(count > 0); //
 
-    *ctn = edx;
     unsigned idx = 0;
     while (idx < 256 && ct1[idx] != 0) {
         idx++;
@@ -91,10 +89,23 @@ unsigned preprocess_calltrick(unsigned char *infile, unsigned insize, unsigned c
     }
     *cti = ~(unsigned char)256;
 
+    if (buf_ptr == buf) {
+        free(buf);
+        return 0;
+    } else {
+        buf_ptr -= 8;
+        unsigned tmp;
+        memcpy(&tmp, *buf_ptr, 4);
+        memcpy(tmp - 4, cti, 1);
+        // TDOO here jmp	@b
+    }
+
     // TODO !
 
-    pack_calltrick_fail:
-    // TODO
+pack_calltrick_fail:
+    *ctn = 0;
+    // ebx = 0; // TODO what
+    return 0;    // 0?
 }
 
 
@@ -226,7 +237,7 @@ int main(int argc, char *argv[])
     outfilebest = outfile;
     unsigned method = METHOD_LZMA;
 
-    unsigned char ct1[256]; // TODO zero out or place it zeroable space
+    unsigned char ct1[256];
     unsigned ctn;
     unsigned char cti;