[dpdk-dev] [RFC 4/7] l3fwd: rework long options parsing

[Olivier Matz <olivier.matz@6wind.com>]

Avoid the use of several strncpy() since getopt is able to
map a long option with an id, which can be matched in the
same switch/case than short options.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
---
 examples/l3fwd/main.c | 167 ++++++++++++++++++++++++++------------------------
 1 file changed, 86 insertions(+), 81 deletions(-)

diff --git a/examples/l3fwd/main.c b/examples/l3fwd/main.c
index 328bae2..9894a3b 100644
--- a/examples/l3fwd/main.c
+++ b/examples/l3fwd/main.c
@@ -474,6 +474,13 @@ parse_eth_dest(const char *optarg)
 #define MAX_JUMBO_PKT_LEN  9600
 #define MEMPOOL_CACHE_SIZE 256
 
+static const char short_options[] =
+	"p:"  /* portmask */
+	"P"   /* promiscuous */
+	"L"   /* enable long prefix match */
+	"E"   /* enable exact match */
+	;
+
 #define CMD_LINE_OPT_CONFIG "config"
 #define CMD_LINE_OPT_ETH_DEST "eth-dest"
 #define CMD_LINE_OPT_NO_NUMA "no-numa"
@@ -481,6 +488,31 @@ parse_eth_dest(const char *optarg)
 #define CMD_LINE_OPT_ENABLE_JUMBO "enable-jumbo"
 #define CMD_LINE_OPT_HASH_ENTRY_NUM "hash-entry-num"
 #define CMD_LINE_OPT_PARSE_PTYPE "parse-ptype"
+enum {
+	/* long options mapped to a short option */
+
+	/* first long only option value must be >= 256, so that we won't
+	 * conflict with short options */
+	CMD_LINE_OPT_MIN_NUM = 256,
+	CMD_LINE_OPT_CONFIG_NUM,
+	CMD_LINE_OPT_ETH_DEST_NUM,
+	CMD_LINE_OPT_NO_NUMA_NUM,
+	CMD_LINE_OPT_IPV6_NUM,
+	CMD_LINE_OPT_ENABLE_JUMBO_NUM,
+	CMD_LINE_OPT_HASH_ENTRY_NUM_NUM,
+	CMD_LINE_OPT_PARSE_PTYPE_NUM,
+};
+
+static const struct option lgopts[] = {
+	{CMD_LINE_OPT_CONFIG, 1, 0, CMD_LINE_OPT_CONFIG_NUM},
+	{CMD_LINE_OPT_ETH_DEST, 1, 0, CMD_LINE_OPT_ETH_DEST_NUM},
+	{CMD_LINE_OPT_NO_NUMA, 0, 0, CMD_LINE_OPT_NO_NUMA_NUM},
+	{CMD_LINE_OPT_IPV6, 0, 0, CMD_LINE_OPT_IPV6_NUM},
+	{CMD_LINE_OPT_ENABLE_JUMBO, 0, 0, CMD_LINE_OPT_ENABLE_JUMBO_NUM},
+	{CMD_LINE_OPT_HASH_ENTRY_NUM, 1, 0, CMD_LINE_OPT_HASH_ENTRY_NUM_NUM},
+	{CMD_LINE_OPT_PARSE_PTYPE, 0, 0, CMD_LINE_OPT_PARSE_PTYPE_NUM},
+	{NULL, 0, 0, 0}
+};
 
 /*
  * This expression is used to calculate the number of mbufs needed
@@ -504,16 +536,6 @@ parse_args(int argc, char **argv)
 	char **argvopt;
 	int option_index;
 	char *prgname = argv[0];
-	static struct option lgopts[] = {
-		{CMD_LINE_OPT_CONFIG, 1, 0, 0},
-		{CMD_LINE_OPT_ETH_DEST, 1, 0, 0},
-		{CMD_LINE_OPT_NO_NUMA, 0, 0, 0},
-		{CMD_LINE_OPT_IPV6, 0, 0, 0},
-		{CMD_LINE_OPT_ENABLE_JUMBO, 0, 0, 0},
-		{CMD_LINE_OPT_HASH_ENTRY_NUM, 1, 0, 0},
-		{CMD_LINE_OPT_PARSE_PTYPE, 0, 0, 0},
-		{NULL, 0, 0, 0}
-	};
 
 	argvopt = argv;
 
@@ -563,88 +585,71 @@ parse_args(int argc, char **argv)
 			break;
 
 		/* long options */
-		case 0:
-			if (!strncmp(lgopts[option_index].name,
-					CMD_LINE_OPT_CONFIG,
-					sizeof(CMD_LINE_OPT_CONFIG))) {
-
-				ret = parse_config(optarg);
-				if (ret) {
-					printf("%s\n", str5);
-					print_usage(prgname);
-					return -1;
-				}
-			}
-
-			if (!strncmp(lgopts[option_index].name,
-					CMD_LINE_OPT_ETH_DEST,
-					sizeof(CMD_LINE_OPT_ETH_DEST))) {
-					parse_eth_dest(optarg);
-			}
-
-			if (!strncmp(lgopts[option_index].name,
-					CMD_LINE_OPT_NO_NUMA,
-					sizeof(CMD_LINE_OPT_NO_NUMA))) {
-				printf("%s\n", str6);
-				numa_on = 0;
+		case CMD_LINE_OPT_CONFIG_NUM:
+			ret = parse_config(optarg);
+			if (ret) {
+				printf("%s\n", str5);
+				print_usage(prgname);
+				return -1;
 			}
+			break;
 
-			if (!strncmp(lgopts[option_index].name,
-				CMD_LINE_OPT_IPV6,
-				sizeof(CMD_LINE_OPT_IPV6))) {
-				printf("%sn", str7);
-				ipv6 = 1;
-			}
+		case CMD_LINE_OPT_ETH_DEST_NUM:
+			parse_eth_dest(optarg);
+			break;
 
-			if (!strncmp(lgopts[option_index].name,
-					CMD_LINE_OPT_ENABLE_JUMBO,
-					sizeof(CMD_LINE_OPT_ENABLE_JUMBO))) {
-				struct option lenopts = {
-					"max-pkt-len", required_argument, 0, 0
-				};
-
-				printf("%s\n", str8);
-				port_conf.rxmode.jumbo_frame = 1;
-
-				/*
-				 * if no max-pkt-len set, use the default
-				 * value ETHER_MAX_LEN.
-				 */
-				if (0 == getopt_long(argc, argvopt, "",
-						&lenopts, &option_index)) {
-					ret = parse_max_pkt_len(optarg);
-					if ((ret < 64) ||
-						(ret > MAX_JUMBO_PKT_LEN)) {
-						printf("%s\n", str9);
-						print_usage(prgname);
-						return -1;
-					}
-					port_conf.rxmode.max_rx_pkt_len = ret;
-				}
-				printf("%s %u\n", str10,
-				(unsigned int)port_conf.rxmode.max_rx_pkt_len);
-			}
+		case CMD_LINE_OPT_NO_NUMA_NUM:
+			printf("%s\n", str6);
+			numa_on = 0;
+			break;
 
-			if (!strncmp(lgopts[option_index].name,
-				CMD_LINE_OPT_HASH_ENTRY_NUM,
-				sizeof(CMD_LINE_OPT_HASH_ENTRY_NUM))) {
+		case CMD_LINE_OPT_IPV6_NUM:
+			printf("%sn", str7);
+			ipv6 = 1;
+			break;
 
-				ret = parse_hash_entry_number(optarg);
-				if ((ret > 0) && (ret <= L3FWD_HASH_ENTRIES)) {
-					hash_entry_number = ret;
-				} else {
-					printf("%s\n", str11);
+		case CMD_LINE_OPT_ENABLE_JUMBO_NUM: {
+			struct option lenopts = {
+				"max-pkt-len", required_argument, 0, 0
+			};
+
+			printf("%s\n", str8);
+			port_conf.rxmode.jumbo_frame = 1;
+
+			/*
+			 * if no max-pkt-len set, use the default
+			 * value ETHER_MAX_LEN.
+			 */
+			if (0 == getopt_long(argc, argvopt, "",
+					&lenopts, &option_index)) {
+				ret = parse_max_pkt_len(optarg);
+				if ((ret < 64) ||
+					(ret > MAX_JUMBO_PKT_LEN)) {
+					printf("%s\n", str9);
 					print_usage(prgname);
 					return -1;
 				}
+				port_conf.rxmode.max_rx_pkt_len = ret;
 			}
+			printf("%s %u\n", str10,
+				(unsigned int)port_conf.rxmode.max_rx_pkt_len);
+			break;
+		}
 
-			if (!strncmp(lgopts[option_index].name,
-				     CMD_LINE_OPT_PARSE_PTYPE,
-				     sizeof(CMD_LINE_OPT_PARSE_PTYPE))) {
-				printf("soft parse-ptype is enabled\n");
-				parse_ptype = 1;
+		case CMD_LINE_OPT_HASH_ENTRY_NUM_NUM:
+			ret = parse_hash_entry_number(optarg);
+			if ((ret > 0) && (ret <= L3FWD_HASH_ENTRIES)) {
+				hash_entry_number = ret;
+			} else {
+				printf("%s\n", str11);
+				print_usage(prgname);
+				return -1;
 			}
+			break;
+
+		case CMD_LINE_OPT_PARSE_PTYPE_NUM:
+			printf("soft parse-ptype is enabled\n");
+			parse_ptype = 1;
 
 			break;
 
-- 
2.8.1