libxl: Make libxl__zalloc et al tolerate a NULL gc

Arrange that if we pass NULL as a gc, we simply don't register the
pointer.  This instantly gives us non-gc'ing but error-checking
versions of malloc, realloc, vasprintf, etc.

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

1 files changed, 4 insertions, 1 deletions

diff --git a/tools/libxl/libxl_internal.c b/tools/libxl/libxl_internal.c
index 4ed941233c..b89aef71ce 100644
--- a/tools/libxl/libxl_internal.c
+++ b/tools/libxl/libxl_internal.c
@@ -34,6 +34,9 @@ void libxl__ptr_add(libxl__gc *gc, void *ptr)
 {
     int i;
 
+    if (!gc)
+        return;
+
     if (!ptr)
         return;
 
@@ -101,7 +104,7 @@ 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) {
+    } else if (new_ptr != ptr && gc != NULL) {
         for (i = 0; i < gc->alloc_maxsize; i++) {
             if (gc->alloc_ptrs[i] == ptr) {
                 gc->alloc_ptrs[i] = new_ptr;