Proper error handling in rpmDigestDup()

- tolerate calling with NULL
- avoid allocations in case of failure
- return NULL instead of calling exit(), ick

diff --git a/rpmio/digest.c b/rpmio/digest.c
index 5a5dfd9..09002d8 100644 (file)
--- a/rpmio/digest.c
+++ b/rpmio/digest.c
@@ -27,12 +27,13 @@ struct DIGEST_CTX_s {
 DIGEST_CTX
 rpmDigestDup(DIGEST_CTX octx)
 {
-    DIGEST_CTX nctx;
-    nctx = memcpy(xcalloc(1, sizeof(*nctx)), octx, sizeof(*nctx));
-    nctx->hashctx = HASH_Clone(octx->hashctx);
-    if (nctx->hashctx == NULL) {
-       fprintf(stderr, "HASH_Clone failed\n");
-       exit(EXIT_FAILURE);  /* FIX: callers do not bother checking error return */
+    DIGEST_CTX nctx = NULL;
+    if (octx) {
+       HASHContext *hctx = HASH_Clone(octx->hashctx);
+       if (hctx) {
+           nctx = memcpy(xcalloc(1, sizeof(*nctx)), octx, sizeof(*nctx));
+           nctx->hashctx = hctx;
+       }
     }
     return nctx;
 }