From: Ian Jackson <ian.jackson@eu.citrix.com>
Date: Thu, 18 Feb 2016 12:37:04 +0000 (+0000)
Subject: tools: libxl: Simplify logic in libxl__realloc
X-Git-Tag: 4.7.0-rc1~542
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=435bbbc9af0f38d304e8be3a1ba00b99af530d60;p=people%2Fandrewcoop%2Fxen.git

tools: libxl: Simplify logic in libxl__realloc

Replace the loop exit and separate test for loop overrun with an
assert in the loop body.

This simplifies the code.  It also (hopefully) avoids Coverity
thinking that gc->alloc_maxsize might change, resulting in the loop
failing to find the right answer but also failing to abort.

(gc->alloc_maxsize can't change because gcs are all singlethreaded:
either they are on the stack of a specific thread, or they belong to
an ao and are covered by the ctx lock.)

Signed-off-by: Ian Jackson <Ian.Jackson@eu.citrix.com>
Acked-by: Ian Campbell <ian.campbell@citrix.com>
---

diff --git a/tools/libxl/libxl_internal.c b/tools/libxl/libxl_internal.c
index fc81130b8e..e7b765bb99 100644
--- a/tools/libxl/libxl_internal.c
+++ b/tools/libxl/libxl_internal.c
@@ -116,16 +116,13 @@ void *libxl__realloc(libxl__gc *gc, void *ptr, size_t new_size)
     if (ptr == NULL) {
         libxl__ptr_add(gc, new_ptr);
     } else if (new_ptr != ptr && libxl__gc_is_real(gc)) {
-        for (i = 0; i < gc->alloc_maxsize; i++) {
+        for (i = 0; ; i++) {
+            assert(i < gc->alloc_maxsize);
             if (gc->alloc_ptrs[i] == ptr) {
                 gc->alloc_ptrs[i] = new_ptr;
                 break;
             }
         }
-        if (i == gc->alloc_maxsize) {
-            LOG(CRITICAL, "pointer is not tracked by the given gc");
-            abort();
-        }
     }
 
     return new_ptr;