commit 2b84a32fc1f5dc3648bf088a6d85110c1b448f5c
Author: Jared Jennings <jared.jennings.ctr@us.af.mil>
Date:   Thu Mar 27 16:11:59 2014 -0500

    expect digest init and finish functions to indicate success or failure; raise exception on failure

diff --git a/ext/digest/digest.c b/ext/digest/digest.c
index 951f73d..5b82635 100644
--- a/ext/digest/digest.c
+++ b/ext/digest/digest.c
@@ -520,7 +520,7 @@ get_digest_base_metadata(VALUE klass)
     Data_Get_Struct(obj, rb_digest_metadata_t, algo);
 
     switch (algo->api_version) {
-      case 2:
+      case 3:
         break;
 
       /*
@@ -548,7 +548,9 @@ rb_digest_base_alloc(VALUE klass)
     algo = get_digest_base_metadata(klass);
 
     pctx = xmalloc(algo->ctx_size);
-    algo->init_func(pctx);
+    if (algo->init_func(pctx) != 1) {
+      rb_raise(rb_eRuntimeError, "Digest initialization failed.");
+    }
 
     obj = Data_Wrap_Struct(klass, 0, xfree, pctx);
 
@@ -586,7 +588,9 @@ rb_digest_base_reset(VALUE self)
 
     Data_Get_Struct(self, void, pctx);
 
-    algo->init_func(pctx);
+    if (algo->init_func(pctx) != 1) {
+      rb_raise(rb_eRuntimeError, "Digest initialization failed.");
+    }
 
     return self;
 }
@@ -624,7 +628,9 @@ rb_digest_base_finish(VALUE self)
     algo->finish_func(pctx, (unsigned char *)RSTRING_PTR(str));
 
     /* avoid potential coredump caused by use of a finished context */
-    algo->init_func(pctx);
+    if (algo->init_func(pctx) != 1) {
+      rb_raise(rb_eRuntimeError, "Digest initialization failed.");
+    }
 
     return str;
 }
diff --git a/ext/digest/digest.h b/ext/digest/digest.h
index 89b26d8..56b7566 100644
--- a/ext/digest/digest.h
+++ b/ext/digest/digest.h
@@ -15,11 +15,11 @@
 
 #include "ruby.h"
 
-#define RUBY_DIGEST_API_VERSION	2
+#define RUBY_DIGEST_API_VERSION	3
 
-typedef void (*rb_digest_hash_init_func_t)(void *);
+typedef int (*rb_digest_hash_init_func_t)(void *);
 typedef void (*rb_digest_hash_update_func_t)(void *, unsigned char *, size_t);
-typedef void (*rb_digest_hash_finish_func_t)(void *, unsigned char *);
+typedef int (*rb_digest_hash_finish_func_t)(void *, unsigned char *);
 
 typedef struct {
     int api_version;