[dpdk-dev] [PATCH v3 1/4] lpm: allocation of an existing object should fail

[Olivier Matz]

Change rte_lpm*_create() functions to return NULL and set rte_errno to
EEXIST when the object name already exists. This is the behavior
described in the API documentation in the header file.

These functions were returning a pointer to the existing object in that
case, but it is a problem as the caller did not know if the object had
to be freed or not.

Doing this change also makes the lpm API more consistent with the other
APIs (mempool, rings, ...).

Fixes: 899d8bc9b3 ("lpm: make tailq fully local")
Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
---
 app/test/test_lpm6.c      |  2 +-
 lib/librte_lpm/rte_lpm.c  | 10 ++++++++--
 lib/librte_lpm/rte_lpm6.c |  5 ++++-
 3 files changed, 13 insertions(+), 4 deletions(-)

diff --git a/app/test/test_lpm6.c b/app/test/test_lpm6.c
index 1f88d7a..b464342 100644
--- a/app/test/test_lpm6.c
+++ b/app/test/test_lpm6.c
@@ -222,7 +222,7 @@ test1(void)
 
 	/* rte_lpm6_create: lpm name == LPM2 */
 	lpm3 = rte_lpm6_create("LPM1", SOCKET_ID_ANY, &config);
-	TEST_LPM_ASSERT(lpm3 == lpm1);
+	TEST_LPM_ASSERT(lpm3 == NULL);
 
 	rte_lpm6_free(lpm1);
 	rte_lpm6_free(lpm2);
diff --git a/lib/librte_lpm/rte_lpm.c b/lib/librte_lpm/rte_lpm.c
index bd3563f..8bdf606 100644
--- a/lib/librte_lpm/rte_lpm.c
+++ b/lib/librte_lpm/rte_lpm.c
@@ -209,8 +209,11 @@ rte_lpm_create_v20(const char *name, int socket_id, int max_rules,
 		if (strncmp(name, lpm->name, RTE_LPM_NAMESIZE) == 0)
 			break;
 	}
-	if (te != NULL)
+	lpm = NULL;
+	if (te != NULL) {
+		rte_errno = EEXIST;
 		goto exit;
+	}
 
 	/* allocate tailq entry */
 	te = rte_zmalloc("LPM_TAILQ_ENTRY", sizeof(*te), 0);
@@ -280,8 +283,11 @@ rte_lpm_create_v1604(const char *name, int socket_id,
 		if (strncmp(name, lpm->name, RTE_LPM_NAMESIZE) == 0)
 			break;
 	}
-	if (te != NULL)
+	lpm = NULL;
+	if (te != NULL) {
+		rte_errno = EEXIST;
 		goto exit;
+	}
 
 	/* allocate tailq entry */
 	te = rte_zmalloc("LPM_TAILQ_ENTRY", sizeof(*te), 0);
diff --git a/lib/librte_lpm/rte_lpm6.c b/lib/librte_lpm/rte_lpm6.c
index 4c44cd7..ba4353c 100644
--- a/lib/librte_lpm/rte_lpm6.c
+++ b/lib/librte_lpm/rte_lpm6.c
@@ -182,8 +182,11 @@ rte_lpm6_create(const char *name, int socket_id,
 		if (strncmp(name, lpm->name, RTE_LPM6_NAMESIZE) == 0)
 			break;
 	}
-	if (te != NULL)
+	lpm = NULL;
+	if (te != NULL) {
+		rte_errno = EEXIST;
 		goto exit;
+	}
 
 	/* allocate tailq entry */
 	te = rte_zmalloc("LPM6_TAILQ_ENTRY", sizeof(*te), 0);
-- 
2.1.4