WT-2375 Use WT_EXTENSION API to unpack, for portability.

In addition, various naming cleanups and error path simplification.

1 files changed, 76 insertions, 85 deletions

diff --git a/ext/collators/revint/revint_collator.c b/ext/collators/revint/revint_collator.c
index 3cc251c6c4a..1e432842caf 100644
--- a/ext/collators/revint/revint_collator.c
+++ b/ext/collators/revint/revint_collator.c
@@ -27,121 +27,103 @@
  */
 
 #include <stdlib.h>
-
-#include <wiredtiger_ext.h>
 #include <errno.h>
 #include <stdint.h>
+#include <wiredtiger_ext.h>
 
 /*
- * Set up a collator used with indices having a single integer key,
- * where the ordering is descending (reversed).
+ * A simple WiredTiger collator for indices having a single integer key,
+ * where the ordering is descending (reversed).  This collator also
+ * requires that primary key be an integer.
  */
 
-/*
- * collate_error --
- *	Handle errors in the collator in a standard way.
- */
-static void
-collate_error(int ret, const char *description)
-{
-	fprintf(stderr, "revint_collator error: %s: %s\n",
-	    wiredtiger_strerror(ret), description);
-	/*
-	 * For errors, we call abort. Since this collator is used in testing
-	 * WiredTiger, we want it to immediately fail hard. A product-ready
-	 * version of this function would not abort.
-	 */
-	abort();
-}
+/* Local collator structure. */
+typedef struct {
+	WT_COLLATOR collator;		/* Must come first */
+	WT_EXTENSION_API *wt_api;	/* Extension API */
+} REVINT_COLLATOR;
 
 /*
- * collate_revint --
+ * revint_compare --
  *	WiredTiger reverse integer collation, used for tests.
  */
 static int
-collate_revint(WT_COLLATOR *collator,
+revint_compare(WT_COLLATOR *collator,
     WT_SESSION *session, const WT_ITEM *k1, const WT_ITEM *k2, int *cmp)
 {
-	WT_PACK_STREAM *s1, *s2;
+	const REVINT_COLLATOR *revint_collator;
+	WT_EXTENSION_API *wtapi;
 	int ret;
 	int64_t i1, i2, p1, p2;
 
-	(void)collator;					/* Unused */
-	(void)session;
-
-	s1 = NULL;
-	s2 = NULL;
+	i1 = i2 = p1 = p2 = 0;
+	revint_collator = (const REVINT_COLLATOR *)collator;
+	wtapi = revint_collator->wt_api;
 
 	/*
 	 * All indices using this collator have an integer key, and the
-	 * primary key is also an integer. A collator is passed the
+	 * primary key is also an integer. A collator is usually passed the
 	 * concatenation of index key and primary key (when available),
-	 * hence we unpack using "ii".
+	 * hence we initially unpack using "ii".
+	 *
+	 * A collator may also be called with an item that includes a index
+	 * key and no primary key.  Among items having the same index key,
+	 * an item with no primary key should sort before an item with a
+	 * primary key. The reason is that if the application calls
+	 * WT_CURSOR::search on a index key for which there are more than
+	 * one value, the search key will not yet have a primary key.  We
+	 * want to position the cursor at the 'first' matching index key so
+	 * that repeated calls to WT_CURSOR::next will see them all.
+	 *
+	 * To keep this code simple, we do not reverse the ordering
+	 * when comparing primary keys.
 	 */
-	if ((ret = wiredtiger_unpack_start(session, "ii",
-	    k1->data, k1->size, &s1)) != 0 ||
-	    (ret = wiredtiger_unpack_start(session, "ii",
-	    k2->data, k2->size, &s2)) != 0)
-		collate_error(ret, "unpack start");
-		/* does not return */
-
-	if ((ret = wiredtiger_unpack_int(s1, &i1)) != 0)
-		collate_error(ret, "unpack index key 1");
-	if ((ret = wiredtiger_unpack_int(s2, &i2)) != 0)
-		collate_error(ret, "unpack index key 2");
+	if ((ret = wtapi->struct_unpack(wtapi, session,
+	    k1->data, k1->size, "ii", &i1, &p1)) != 0) {
+		/* could be missing primary key, try again without */
+		if ((ret = wtapi->struct_unpack(wtapi, session,
+		    k1->data, k1->size, "i", &i1)) != 0)
+			return (ret);
+		p1 = INT64_MIN;	/* sort this first */
+	}
+	if ((ret = wtapi->struct_unpack(wtapi, session,
+	    k2->data, k2->size, "ii", &i2, &p2)) != 0) {
+		/* could be missing primary key, try again without */
+		if ((ret = wtapi->struct_unpack(wtapi, session,
+		    k2->data, k2->size, "i", &i2)) != 0)
+			return (ret);
+		p2 = INT64_MIN;	/* sort this first */
+	}
 
 	/* sorting is reversed */
 	if (i1 < i2)
 		*cmp = 1;
 	else if (i1 > i2)
 		*cmp = -1;
-	else {
-		/*
-		 * Compare primary keys next.
-		 *
-		 * Allow failures here.  A collator may be called with an
-		 * item that includes a index key and no primary key.  Among
-		 * items having the same index key, an item with no primary
-		 * key should sort before an item with a primary key. The
-		 * reason is that if the application calls WT_CURSOR::search
-		 * on a index key for which there are more than one value,
-		 * the search key will not yet have a primary key.  We want
-		 * to position the cursor at the 'first' matching index key
-		 * so that repeated calls to WT_CURSOR::next will see them
-		 * all.
-		 *
-		 * To keep this code simple, we do keep secondary sort of
-		 * primary keys in forward (not reversed) order.
-		 */
-		if ((ret = wiredtiger_unpack_int(s1, &p1)) != 0) {
-			if (ret == ENOMEM)
-				p1 = INT64_MIN; /* sort this first */
-			else
-				collate_error(ret, "unpack primary key 1");
-		}
-		if ((ret = wiredtiger_unpack_int(s2, &p2)) != 0) {
-			if (ret == ENOMEM)
-				p2 = INT64_MIN; /* sort this first */
-			else
-				collate_error(ret, "unpack primary key 2");
-		}
-
-		/* sorting is not reversed here */
-		if (p1 < p2)
-			*cmp = -1;
-		else if (p1 > p2)
-			*cmp = 1;
-		else
-			*cmp = 0; /* index key and primary key are same */
-	}
-	if ((ret = wiredtiger_pack_close(s1, NULL)) != 0 ||
-	    (ret = wiredtiger_pack_close(s2, NULL)) != 0)
-		collate_error(ret, "unpack close");
+	/* compare primary keys next, not reversed */
+	else if (p1 < p2)
+		*cmp = -1;
+	else if (p1 > p2)
+		*cmp = 1;
+	else
+		*cmp = 0; /* index key and primary key are same */
 
 	return (0);
 }
 
-static WT_COLLATOR revint_collator = { collate_revint, NULL, NULL };
+/*
+ * revint_terminate --
+ *	Terminate is called to free the collator and any associated memory.
+ */
+static int
+revint_terminate(WT_COLLATOR *collator, WT_SESSION *session)
+{
+	(void)session;				/* Unused parameters */
+
+	/* Free the allocated memory. */
+	free(collator);
+	return (0);
+}
 
 /*
  * wiredtiger_extension_init --
@@ -150,8 +132,17 @@ static WT_COLLATOR revint_collator = { collate_revint, NULL, NULL };
 int
 wiredtiger_extension_init(WT_CONNECTION *connection, WT_CONFIG_ARG *config)
 {
+	REVINT_COLLATOR *revint_collator;
+
 	(void)config;				/* Unused parameters */
 
+	if ((revint_collator = calloc(1, sizeof(REVINT_COLLATOR))) == NULL)
+		return (errno);
+
+	revint_collator->collator.compare = revint_compare;
+	revint_collator->collator.terminate = revint_terminate;
+	revint_collator->wt_api = connection->get_extension_api(connection);
+
 	return (connection->add_collator(
-	    connection, "revint", &revint_collator, NULL));
+	    connection, "revint", &revint_collator->collator, NULL));
 }