astobj2: Avoid using temporary objects + ao2_find() with OBJ_POINTER.

There is a fairly common pattern making its way through the code base where we
put a temporary object on the stack so we can call ao2_find() with OBJ_POINTER.
The purpose is so that it can be passed into the object hash function.
However, this really seems like a hack and potentially error prone.  This patch
is a first stab at approach to avoid having to do that.

It adds a new flag, OBJ_KEY, which can be used instead of OBJ_POINTER in these
situations.  Then, the hash function can know whether it was given an object or
some custom data to hash.

The patch also changes some uses of ao2_find() for iax2_user and iax2_peer
objects to reflect how OBJ_KEY would be used.

So long, and thanks for all the fish.

Review: https://reviewboard.asterisk.org/r/1184/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@330273 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 38 insertions, 9 deletions

diff --git a/tests/test_astobj2.c b/tests/test_astobj2.c
index 9466f3384..b9e67b5c1 100644
--- a/tests/test_astobj2.c
+++ b/tests/test_astobj2.c
@@ -38,7 +38,6 @@ ASTERISK_FILE_VERSION(__FILE__, "$Revision$")
 #include "asterisk/astobj2.h"
 
 struct test_obj {
-	char c[20];
 	int i;
 	int *destructor_count;
 };
@@ -75,20 +74,35 @@ static int multiple_cb(void *obj, void *arg, int flag)
 static int test_cmp_cb(void *obj, void *arg, int flags)
 {
 	struct test_obj *cmp_obj = (struct test_obj *) obj;
-	struct test_obj *test_obj = (struct test_obj *) arg;
+
 	if (!arg) {
 		return 0;
 	}
-	return (cmp_obj->i == test_obj->i) ? CMP_MATCH | CMP_STOP : 0;
+
+	if (flags & OBJ_KEY) {
+		int *i = (int *) arg;
+		return (cmp_obj->i == *i) ? CMP_MATCH | CMP_STOP : 0;
+	} else {
+		struct test_obj *test_obj = (struct test_obj *) arg;
+		return (cmp_obj->i == test_obj->i) ? CMP_MATCH | CMP_STOP : 0;
+	}
 }
 
 static int test_hash_cb(const void *obj, const int flags)
 {
-	struct test_obj *test_obj = (struct test_obj *) obj;
-	if (!test_obj || ast_strlen_zero(test_obj->c)) {
+	if (!obj) {
 		return 0;
 	}
-	return ast_str_hash(test_obj->c);
+
+	if (flags & OBJ_KEY) {
+		const int *i = obj;
+
+		return *i;
+	} else {
+		const struct test_obj *test_obj = obj;
+
+		return test_obj->i;
+	}
 }
 
 static int astobj2_test_helper(int use_hash, int use_cmp, unsigned int lim, struct ast_test *test)
@@ -128,7 +142,6 @@ static int astobj2_test_helper(int use_hash, int use_cmp, unsigned int lim, stru
 			res = AST_TEST_FAIL;
 			goto cleanup;
 		}
-		snprintf(obj->c, sizeof(obj->c), "zombie #%d", num);
 		obj->destructor_count = &destructor_count;
 		obj->i = num;
 		ao2_link(c1, obj);
@@ -163,7 +176,6 @@ static int astobj2_test_helper(int use_hash, int use_cmp, unsigned int lim, stru
 	num = 75;
 	for (; num; num--) {
 		int i = (ast_random() % ((lim / 2)) + 1); /* find a random object */
-		snprintf(tmp_obj.c, sizeof(tmp_obj.c), "zombie #%d", i);
 		tmp_obj.i = i;
 		if (!(obj = ao2_find(c1, &tmp_obj, OBJ_POINTER))) {
 			res = AST_TEST_FAIL;
@@ -178,6 +190,23 @@ static int astobj2_test_helper(int use_hash, int use_cmp, unsigned int lim, stru
 		}
 	}
 
+	/* Testing ao2_find with OBJ_KEY */
+	num = 75;
+	for (; num; num--) {
+		int i = (ast_random() % ((lim / 2)) + 1); /* find a random object */
+		if (!(obj = ao2_find(c1, &i, OBJ_KEY))) {
+			res = AST_TEST_FAIL;
+			ast_test_status_update(test, "COULD NOT FIND:%d, ao2_find() with OBJ_KEY flag failed.\n", i);
+		} else {
+			/* a correct match will only take place when the custom cmp function is used */
+			if (use_cmp && obj->i != i) {
+				ast_test_status_update(test, "object %d does not match object %d\n", obj->i, tmp_obj.i);
+				res = AST_TEST_FAIL;
+			}
+			ao2_t_ref(obj, -1, "test");
+		}
+	}
+
 	/* Testing ao2_find with OBJ_POINTER | OBJ_UNLINK | OBJ_CONTINUE.
 	 * In this test items are unlinked from c1 and placed in c2.  Then
 	 * unlinked from c2 and placed back into c1.
@@ -374,7 +403,7 @@ AST_TEST_DEFINE(astobj2_test_2)
 	int num;
 	static const int NUM_OBJS = 5;
 	int destructor_count = NUM_OBJS;
-	struct test_obj tmp_obj = { "", };
+	struct test_obj tmp_obj = { 0, };
 
 	switch (cmd) {
 	case TEST_INIT: