[dpdk-dev] [PATCH 06/11] kvargs: simpler parsing and allow duplicated keys

[Olivier Matz]

Remove the rte_kvargs_add_pair() function whose only role was to check
if a key is duplicated. Having duplicated keys is now allowed by kvargs
API.

Also replace rte_strsplit() by more a standard function strtok_r() that
is easier to understand for people already knowing the libc. It also
avoids useless calls to strnlen(). The delimiters macros become strings
instead of chars due to the strtok_r() API.

Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
---
 lib/librte_kvargs/rte_kvargs.c | 71 ++++++++++--------------------------------
 lib/librte_kvargs/rte_kvargs.h |  8 +++--
 2 files changed, 22 insertions(+), 57 deletions(-)

diff --git a/lib/librte_kvargs/rte_kvargs.c b/lib/librte_kvargs/rte_kvargs.c
index 9c52ce4..6aaa316 100644
--- a/lib/librte_kvargs/rte_kvargs.c
+++ b/lib/librte_kvargs/rte_kvargs.c
@@ -32,8 +32,6 @@
  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */
 #include <string.h>
-#include <sys/user.h>
-#include <linux/binfmts.h>
 #include <stdlib.h>
 
 #include <rte_log.h>
@@ -42,38 +40,6 @@
 #include "rte_kvargs.h"
 
 /*
- * Add a key-value pair at the end of a given key/value list.
- * Return an error if the list is full or if the key is duplicated.
- */
-static int
-rte_kvargs_add_pair(struct rte_kvargs *kvlist, char *key, char *val)
-{
-	unsigned i;
-	struct rte_kvargs_pair* entry;
-
-	/* is the list full? */
-	if (kvlist->count >= RTE_KVARGS_MAX) {
-		RTE_LOG(ERR, PMD, "Couldn't add %s, key/value list is full\n", key);
-		return -1;
-	}
-
-	/* Check if the key is duplicated */
-	for (i = 0; i < kvlist->count; i++) {
-		entry = &kvlist->pairs[i];
-		if (strcmp(entry->key, key) == 0) {
-			RTE_LOG(ERR, PMD, "Couldn't add %s, duplicated key\n", key);
-			return -1;
-		}
-	}
-
-	entry = &kvlist->pairs[kvlist->count];
-	entry->key = key;
-	entry->value = val;
-	kvlist->count++;
-	return 0;
-}
-
-/*
  * Receive a string with a list of arguments following the pattern
  * key=value;key=value;... and insert them into the list.
  * strtok() is used so the params string will be copied to be modified.
@@ -81,15 +47,8 @@ rte_kvargs_add_pair(struct rte_kvargs *kvlist, char *key, char *val)
 static int
 rte_kvargs_tokenize(struct rte_kvargs *kvlist, const char *params)
 {
-	unsigned i, count;
-	char *pairs[RTE_KVARGS_MAX];
-	char *pair[2];
-
-	/* If params are empty, nothing to do */
-	if (params == NULL || params[0] == 0) {
-		RTE_LOG(ERR, PMD, "Cannot parse empty arguments\n");
-		return -1;
-	}
+	unsigned i;
+	char *str, *ctx1, *ctx2;
 
 	/* Copy the const char *params to a modifiable string
 	 * to pass to rte_strsplit
@@ -100,27 +59,29 @@ rte_kvargs_tokenize(struct rte_kvargs *kvlist, const char *params)
 		return -1;
 	}
 
-	count = rte_strsplit(kvlist->str, strnlen(kvlist->str, MAX_ARG_STRLEN), pairs,
-			RTE_KVARGS_MAX, RTE_KVARGS_PAIRS_DELIM);
-
-	for (i = 0; i < count; i++) {
-		pair[0] = NULL;
-		pair[1] = NULL;
+	/* browse each key/value pair and add it in kvlist */
+	str = kvlist->str;
+	while ((str = strtok_r(str, RTE_KVARGS_PAIRS_DELIM, &ctx1)) != NULL) {
 
-		rte_strsplit(pairs[i], strnlen(pairs[i], MAX_ARG_STRLEN), pair, 2,
-				RTE_KVARGS_KV_DELIM);
+		i = kvlist->count;
+		if (i >= RTE_KVARGS_MAX) {
+			RTE_LOG(ERR, PMD, "Cannot parse arguments: list full\n");
+			return -1;
+		}
 
-		if (pair[0] == NULL || pair[1] == NULL || pair[0][0] == 0
-				|| pair[1][0] == 0) {
+		kvlist->pairs[i].key = strtok_r(str, RTE_KVARGS_KV_DELIM, &ctx2);
+		kvlist->pairs[i].value = strtok_r(NULL, RTE_KVARGS_KV_DELIM, &ctx2);
+		if (kvlist->pairs[i].key == NULL || kvlist->pairs[i].value == NULL) {
 			RTE_LOG(ERR, PMD,
 				"Cannot parse arguments: wrong key or value\n"
 				"params=<%s>\n", params);
 			return -1;
 		}
 
-		if (rte_kvargs_add_pair(kvlist, pair[0], pair[1]) < 0)
-			return -1;
+		kvlist->count++;
+		str = NULL;
 	}
+
 	return 0;
 }
 
diff --git a/lib/librte_kvargs/rte_kvargs.h b/lib/librte_kvargs/rte_kvargs.h
index 47d78af..352ae9a 100644
--- a/lib/librte_kvargs/rte_kvargs.h
+++ b/lib/librte_kvargs/rte_kvargs.h
@@ -42,6 +42,10 @@
  * This module can be used to parse arguments whose format is
  * key1=value1;key2=value2;key3=value3;...
  *
+ * The same key can appear several times with the same or a different
+ * value. Indeed, the arguments are stored as a list of key/values
+ * associations and not as a dictionary.
+ *
  * This file provides some helpers that are especially used by virtual
  * ethernet devices at initialization for arguments parsing.
  */
@@ -54,10 +58,10 @@ extern "C" {
 #define RTE_KVARGS_MAX 32
 
 /** separator character used between each pair */
-#define RTE_KVARGS_PAIRS_DELIM	';'
+#define RTE_KVARGS_PAIRS_DELIM	";"
 
 /** separator character used between key and value */
-#define RTE_KVARGS_KV_DELIM	'='
+#define RTE_KVARGS_KV_DELIM	"="
 
 /** Type of callback function used by rte_kvargs_process() */
 typedef int (*arg_handler_t)(char *value, void *opaque);
-- 
1.8.4.rc3