Changeset 16164 in vbox for trunk/src/VBox/Runtime

Timestamp:

Jan 22, 2009 1:21:40 PM (16 years ago)

Author:

vboxsync

Message:

rtZipStoreCompress: g++ (GCC) 4.1.2 (Gentoo 4.1.2 p1.1) generates incorrect code if '(uintptr_t)&pZip->abBuffer[sizeof(pZip->abBuffer)] - (uintptr_t)pZip->u.Store.pb' is used to calc remaining buffer space, 'sizeof(pZip->abBuffer) - (size_t)(pbDst - &pZip->abBuffer[0])' seems to work though. (It was looping endlessly, with cb=0, seems it had figured that the branch wasn't gonna be taken then.)

File:

• trunk/src/VBox/Runtime/common/misc/zip.cpp (modified) (4 diffs)

trunk/src/VBox/Runtime/common/misc/zip.cpp

@@ -248 +248 @@
 
 #ifdef RTZIP_USE_STORE
+#include <stdio.h>
 
 /**
@@ -254 +255 @@
 static DECLCALLBACK(int) rtZipStoreCompress(PRTZIPCOMP pZip, const void *pvBuf, size_t cbBuf)
 {
+    uint8_t *pbDst = pZip->u.Store.pb;
     while (cbBuf)
     {
@@ -259 +261 @@
          * Flush.
          */
-        size_t cb = (uintptr_t)&pZip->abBuffer[sizeof(pZip->abBuffer)] - (uintptr_t)pZip->u.Store.pb;
-        if (cb <= 0)
+        size_t cb = sizeof(pZip->abBuffer) - (size_t)(pbDst - &pZip->abBuffer[0]); /* careful here, g++ 4.1.2 screws up easily */
+        if (cb == 0)
         {
             int rc = pZip->pfnOut(pZip->pvUser, &pZip->abBuffer[0], sizeof(pZip->abBuffer));
             if (RT_FAILURE(rc))
                 return rc;
+
             cb = sizeof(pZip->abBuffer);
-            pZip->u.Store.pb = &pZip->abBuffer[0];
+            pbDst = &pZip->abBuffer[0];
         }
 
@@ -274 +277 @@
         if (cbBuf < cb)
             cb = cbBuf;
-        memcpy(pZip->u.Store.pb, pvBuf, cb);
-        pZip->u.Store.pb += cb;
+        memcpy(pbDst, pvBuf, cb);
+
+        pbDst += cb;
         cbBuf -= cb;
         pvBuf = (uint8_t *)pvBuf + cb;
     }
+    pZip->u.Store.pb = pbDst;
     return VINF_SUCCESS;
 }