Changeset 58734 in vbox for trunk/src/libs/xpcom18a4/nsprpub/lib/ds/plarena.h

Timestamp:

Nov 18, 2015 10:24:35 AM (9 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

104171

Message:

libs/xpcom: fix (just in case) for sloppy code

File:

• trunk/src/libs/xpcom18a4/nsprpub/lib/ds/plarena.h (modified) (2 diffs)

trunk/src/libs/xpcom18a4/nsprpub/lib/ds/plarena.h

@@ -109 +109 @@
     PR_BEGIN_MACRO \
         PLArena *_a = (pool)->current; \
-        PRUint32 _nb = PL_ARENA_ALIGN(pool, nb); \
+        PRUint32 _nb = PL_ARENA_ALIGN(pool, (PRUint32)nb); \
         PRUword _p = _a->avail; \
-        PRUword _q = _p + _nb; \
-        if (_q > _a->limit) \
+        if (_nb < (PRUint32)nb) { \
+            _p = 0; \
+        } else if (_nb > (_a->limit - _a->avail)) { \
             _p = (PRUword)PL_ArenaAllocate(pool, _nb); \
-        else \
-            _a->avail = _q; \
+        } else { \
+            _a->avail += _nb; \
+        } \
         p = (void *)_p; \
-        PL_ArenaCountAllocation(pool, nb); \
+        if (p) { \
+            PL_ArenaCountAllocation(pool, nb); \
+        } \
     PR_END_MACRO
 
@@ -123 +127 @@
     PR_BEGIN_MACRO \
         PLArena *_a = (pool)->current; \
-        PRUint32 _incr = PL_ARENA_ALIGN(pool, incr); \
-        PRUword _p = _a->avail; \
-        PRUword _q = _p + _incr; \
-        if (_p == (PRUword)(p) + PL_ARENA_ALIGN(pool, size) && \
-            _q <= _a->limit) { \
-            _a->avail = _q; \
-            PL_ArenaCountInplaceGrowth(pool, size, incr); \
+        PRUint32 _incr = PL_ARENA_ALIGN(pool, (PRUint32)incr); \
+        if (_incr < (PRUint32)incr) { \
+            p = NULL; \
+        } else if (_a->avail == (PRUword)(p) + PL_ARENA_ALIGN(pool, size) && \
+            _incr <= (_a->limit - _a->avail)) { \
+            _a->avail = _incr; \
+            PL_ArenaCountInplaceGrowth(pool, size, (RTUint32)incr); \
         } else { \
-            p = PL_ArenaGrow(pool, p, size, incr); \
-        } \
-        PL_ArenaCountGrowth(pool, size, incr); \
+            p = PL_ArenaGrow(pool, p, size, (PRUint32)incr); \
+        } \
+        if (p) { \
+            PL_ArenaCountGrowth(pool, size, (PRUint32)incr); \
+        } \
     PR_END_MACRO