Add REALLOC macro to simplify realloc error handling

realloc can fail just like the other memory allocation functions. Add a
macro to simplify handling of realloc failures, similar to the already
existing MALLOC, CALLOC, etc.

Replace the existing realloc uses with the new macro, allowing us to
move tedious error handling to the macro. Also, in be_package and
be_sync, this fixes hypothetical memory leaks (and thereafter null
pointer dereferences) in case realloc fails to shrink the allocated
memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Allan McRae <allan@archlinux.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/lib/libalpm/util.h b/lib/libalpm/util.h
index 675eedec..3306a022 100644
--- a/lib/libalpm/util.h
+++ b/lib/libalpm/util.h
@@ -53,6 +53,7 @@ void _alpm_alloc_fail(size_t size);
 
 #define MALLOC(p, s, action) do { p = malloc(s); if(p == NULL) { _alpm_alloc_fail(s); action; } } while(0)
 #define CALLOC(p, l, s, action) do { p = calloc(l, s); if(p == NULL) { _alpm_alloc_fail(l * s); action; } } while(0)
+#define REALLOC(p, s, action) do { void* np = realloc(p, s); if(np == NULL) { _alpm_alloc_fail(s); action; } else { p = np; } } while(0)
 /* This strdup macro is NULL safe- copying NULL will yield NULL */
 #define STRDUP(r, s, action) do { if(s != NULL) { r = strdup(s); if(r == NULL) { _alpm_alloc_fail(strlen(s)); action; } } else { r = NULL; } } while(0)
 #define STRNDUP(r, s, l, action) do { if(s != NULL) { r = strndup(s, l); if(r == NULL) { _alpm_alloc_fail(l); action; } } else { r = NULL; } } while(0)