classid auto generation if provided tc name does not exist

Manually editing etc/libnl/classid before adding tc objects is a pain.
This patch adds code to attempt auto generating a unique tc id which
will then be assigned to the provided name and added to the classid
file.

This will make the following commands work with prior definitions of
the names "top" and "test"
	sudo sbin/nl-qdisc-add --dev eth0 --parent root --id top htb
	sudo sbin/nl-class-add --dev eth0 --parent top --id test htb --rate 100mbit

It will generate the following ids automatically:
4001:			top
4001:1			test

14 files changed, 162 insertions, 47 deletions

diff --git a/etc/classid b/etc/classid
index 76a11f2..2203243 100644
--- a/etc/classid
+++ b/etc/classid
@@ -32,5 +32,14 @@ ffff:ffff		root
 ffff:fff1		ingress
 
 #
-# List your classid definitions below:
+# List your classid definitions here:
 #
+
+
+
+###############################################################################
+# List of auto-generated classids
+#
+# DO NOT ADD CLASSID DEFINITIONS BELOW THIS LINE
+#
+# <CLASSID>		<NAME>
diff --git a/include/netlink/cli/tc.h b/include/netlink/cli/tc.h
index 762cc69..82f9a1d 100644
--- a/include/netlink/cli/tc.h
+++ b/include/netlink/cli/tc.h
@@ -16,7 +16,7 @@
 
 extern void nl_cli_tc_parse_dev(struct rtnl_tc *, struct nl_cache *, char *);
 extern void nl_cli_tc_parse_parent(struct rtnl_tc *, char *);
-extern void nl_cli_tc_parse_handle(struct rtnl_tc *, char *);
+extern void nl_cli_tc_parse_handle(struct rtnl_tc *, char *, int);
 extern void nl_cli_tc_parse_mtu(struct rtnl_tc *, char *);
 extern void nl_cli_tc_parse_mpu(struct rtnl_tc *, char *);
 extern void nl_cli_tc_parse_overhead(struct rtnl_tc *, char *);
diff --git a/include/netlink/route/tc.h b/include/netlink/route/tc.h
index b4e953e..f1e8605 100644
--- a/include/netlink/route/tc.h
+++ b/include/netlink/route/tc.h
@@ -66,6 +66,8 @@ extern int		rtnl_tc_calc_cell_log(int);
 extern int		rtnl_tc_read_classid_file(void);
 extern char *		rtnl_tc_handle2str(uint32_t, char *, size_t);
 extern int		rtnl_tc_str2handle(const char *, uint32_t *);
+extern int		rtnl_classid_generate(const char *, uint32_t *,
+					      uint32_t);
 
 #ifdef __cplusplus
 }
diff --git a/lib/route/classid.c b/lib/route/classid.c
index 5650a20..0cb89b5 100644
--- a/lib/route/classid.c
+++ b/lib/route/classid.c
@@ -75,6 +75,20 @@ static int classid_lookup(const char *name, uint32_t *result)
 	return -NLE_OBJ_NOTFOUND;
 }
 
+static char *name_lookup(const uint32_t classid)
+{
+	void *res;
+	struct classid_map cm = {
+		.classid = classid,
+		.name = "search entry",
+	};
+
+	if ((res = tfind(&cm, &id_root, &compare_id)))
+		return (*(struct classid_map **) res)->name;
+
+	return NULL;
+}
+
 /**
  * @name Traffic Control Handle Translations
  * @{
@@ -101,14 +115,10 @@ char * rtnl_tc_handle2str(uint32_t handle, char *buf, size_t len)
 	else if (TC_H_INGRESS == handle)
 		snprintf(buf, len, "ingress");
 	else {
-		void *res;
-		struct classid_map cm = {
-			.classid = handle,
-			.name = "search entry",
-		};
-
-		if ((res = tfind(&cm, &id_root, &compare_id)))
-			snprintf(buf, len, "%s", (*(struct classid_map **) res)->name);
+		char *name;
+
+		if ((name = name_lookup(handle)))
+			snprintf(buf, len, "%s", name);
 		else if (0 == TC_H_MAJ(handle))
 			snprintf(buf, len, ":%02x", TC_H_MIN(handle));
 		else if (0 == TC_H_MIN(handle))
@@ -232,6 +242,15 @@ static void free_nothing(void *arg)
 {
 }
 
+static void classid_map_free(struct classid_map *map)
+{
+	if (!map)
+		return;
+
+	free(map->name);
+	free(map);
+}
+
 static void clear_hashtable(void)
 {
 	int i;
@@ -239,10 +258,8 @@ static void clear_hashtable(void)
 	for (i = 0; i < CLASSID_NAME_HT_SIZ; i++) {
 		struct classid_map *map, *n;
 
-		nl_list_for_each_entry_safe(map, n, &tbl_name[i], name_list) {
-			free(map->name);
-			free(map);
-		}
+		nl_list_for_each_entry_safe(map, n, &tbl_name[i], name_list)
+			classid_map_free(map);
 
 		nl_init_list_head(&tbl_name[i]);
 
@@ -254,6 +271,28 @@ static void clear_hashtable(void)
 	}
 }
 
+static int classid_map_add(uint32_t classid, const char *name)
+{
+	struct classid_map *map;
+	int n;
+
+	if (!(map = calloc(1, sizeof(*map))))
+		return -NLE_NOMEM;
+
+	map->classid = classid;
+	map->name = strdup(name);
+
+	n = classid_tbl_hash(map->name);
+	nl_list_add_tail(&map->name_list, &tbl_name[n]);
+
+	if (!tsearch((void *) map, &id_root, &compare_id)) {
+		classid_map_free(map);
+		return -NLE_NOMEM;
+	}
+
+	return 0;
+}
+
 /**
  * (Re-)read classid file
  * 
@@ -289,10 +328,8 @@ int rtnl_tc_read_classid_file(void)
 	clear_hashtable();
 
 	while (fgets(buf, sizeof(buf), fd)) {
-		struct classid_map *map;
 		uint32_t classid;
 		char *ptr, *tok;
-		int n;
 
 		/* ignore comments and empty lines */
 		if (*buf == '#' || *buf == '\n' || *buf == '\r')
@@ -312,21 +349,8 @@ int rtnl_tc_read_classid_file(void)
 			goto errout_close;
 		}
 
-		if (!(map = calloc(1, sizeof(*map)))) {
-			err = -NLE_NOMEM;
+		if ((err = classid_map_add(classid, tok)) < 0)
 			goto errout_close;
-		}
-
-		map->classid = classid;
-		map->name = strdup(tok);
-
-		n = classid_tbl_hash(map->name);
-		nl_list_add_tail(&map->name_list, &tbl_name[n]);
-
-		if (!tsearch((void *) map, &id_root, &compare_id)) {
-			err = -NLE_NOMEM;
-			goto errout_close;
-		}
 	}
 
 	err = 0;
@@ -341,6 +365,64 @@ errout:
 
 }
 
+int rtnl_classid_generate(const char *name, uint32_t *result, uint32_t parent)
+{
+	static uint32_t base = 0x4000 << 16;
+	uint32_t classid;
+	char *path;
+	FILE *fd;
+	int err = 0;
+
+	if (parent == TC_H_ROOT || parent == TC_H_INGRESS) {
+		do {
+			base += (1 << 16);
+			if (base == TC_H_MAJ(TC_H_ROOT))
+				base = 0x4000 << 16;
+		} while (name_lookup(base));
+
+		classid = base;
+	} else {
+		classid = TC_H_MAJ(parent);
+		do {
+			if (++classid == TC_H_MIN(TC_H_ROOT))
+				return -NLE_RANGE;
+		} while (name_lookup(base));
+	}
+
+	NL_DBG(2, "Generated new classid %#x\n", classid);
+
+	if (asprintf(&path, "%s/classid", SYSCONFDIR) < 0)
+		return -NLE_NOMEM;
+
+	if (!(fd = fopen(path, "a"))) {
+		err = -nl_syserr2nlerr(errno);
+		goto errout;
+	}
+
+	fprintf(fd, "%x:", TC_H_MAJ(classid) >> 16);
+	if (TC_H_MIN(classid))
+		fprintf(fd, "%x", TC_H_MIN(classid));
+	fprintf(fd, "\t\t\t%s\n", name);
+
+	fclose(fd);
+
+	if ((err = classid_map_add(classid, name)) < 0) {
+		/* 
+		 * Error adding classid map, re-read classid file is best
+		 * option here. It is likely to fail as well but better
+		 * than nothing, entry was added to the file already anyway.
+		 */
+		rtnl_tc_read_classid_file();
+	}
+
+	*result = classid;
+	err = 0;
+errout:
+	free(path);
+
+	return err;
+}
+
 /** @} */
 
 static void __init classid_init(void)
diff --git a/src/lib/tc.c b/src/lib/tc.c
index 5f39498..72407cf 100644
--- a/src/lib/tc.c
+++ b/src/lib/tc.c
@@ -42,14 +42,21 @@ void nl_cli_tc_parse_parent(struct rtnl_tc *tc, char *arg)
 	rtnl_tc_set_parent(tc, parent);
 }
 
-void nl_cli_tc_parse_handle(struct rtnl_tc *tc, char *arg)
+void nl_cli_tc_parse_handle(struct rtnl_tc *tc, char *arg, int create)
 {
-	uint32_t handle;
+	uint32_t handle, parent;
 	int err;
 
-	if ((err = rtnl_tc_str2handle(arg, &handle)) < 0)
-		nl_cli_fatal(err, "Unable to parse handle \"%s\": %s",
-		      arg, nl_geterror(err));
+	parent = rtnl_tc_get_parent(tc);
+
+	if ((err = rtnl_tc_str2handle(arg, &handle)) < 0) {
+		if (err == -NLE_OBJ_NOTFOUND && create)
+			err = rtnl_classid_generate(arg, &handle, parent);
+
+		if (err < 0)
+			nl_cli_fatal(err, "Unable to parse handle \"%s\": %s",
+				     arg, nl_geterror(err));
+	}
 
 	rtnl_tc_set_handle(tc, handle);
 }
diff --git a/src/nl-class-add.c b/src/nl-class-add.c
index 553dec1..80ea826 100644
--- a/src/nl-class-add.c
+++ b/src/nl-class-add.c
@@ -59,7 +59,7 @@ int main(int argc, char *argv[])
 	struct nl_cli_qdisc_module *qm;
 	struct rtnl_class_ops *ops;
 	int err, flags = NLM_F_CREATE | NLM_F_EXCL;
-	char *kind;
+	char *kind, *id = NULL;
  
 	sock = nl_cli_alloc_socket();
 	nl_cli_connect(sock, NETLINK_ROUTE);
@@ -106,7 +106,7 @@ int main(int argc, char *argv[])
 		case 'v': nl_cli_print_version(); break;
 		case 'd': nl_cli_tc_parse_dev(tc, link_cache, optarg); break;
 		case 'p': nl_cli_tc_parse_parent(tc, optarg); break;
-		case 'i': nl_cli_tc_parse_handle(tc, optarg); break;
+		case 'i': id = strdup(optarg); break;
 		case ARG_UPDATE: flags = NLM_F_CREATE; break;
 		case ARG_UPDATE_ONLY: flags = 0; break;
 		case ARG_MTU: nl_cli_tc_parse_mtu(tc, optarg); break;
@@ -125,6 +125,11 @@ int main(int argc, char *argv[])
 	if (!rtnl_tc_get_parent(tc))
 		nl_cli_fatal(EINVAL, "You must specify a parent (--parent=XXX)");
 
+	if (id) {
+		nl_cli_tc_parse_handle(tc, id, 1);
+		free(id);
+	}
+
 	kind = argv[optind++];
 	rtnl_class_set_kind(class, kind);
 
diff --git a/src/nl-class-delete.c b/src/nl-class-delete.c
index 94a6ab4..3c5cdc1 100644
--- a/src/nl-class-delete.c
+++ b/src/nl-class-delete.c
@@ -109,7 +109,7 @@ int main(int argc, char *argv[])
 		case 'v': nl_cli_print_version(); break;
 		case 'd': nl_cli_tc_parse_dev(tc, link_cache, optarg); break;
 		case 'p': nl_cli_tc_parse_parent(tc, optarg); break;
-		case 'i': nl_cli_tc_parse_handle(tc, optarg); break;
+		case 'i': nl_cli_tc_parse_handle(tc, optarg, 0); break;
 		case 'k': nl_cli_class_parse_kind(class, optarg); break;
 		}
  	}
diff --git a/src/nl-class-list.c b/src/nl-class-list.c
index 3a38555..fccc512 100644
--- a/src/nl-class-list.c
+++ b/src/nl-class-list.c
@@ -103,7 +103,7 @@ int main(int argc, char *argv[])
 		case 'v': nl_cli_print_version(); break;
 		case 'd': nl_cli_tc_parse_dev(tc, link_cache, optarg); break;
 		case 'p': nl_cli_tc_parse_parent(tc, optarg); break;
-		case 'i': nl_cli_tc_parse_handle(tc, optarg); break;
+		case 'i': nl_cli_tc_parse_handle(tc, optarg, 0); break;
 		case 'k': nl_cli_class_parse_kind(class, optarg); break;
 		}
  	}
diff --git a/src/nl-cls-add.c b/src/nl-cls-add.c
index 5e2c2dc..fad9313 100644
--- a/src/nl-cls-add.c
+++ b/src/nl-cls-add.c
@@ -59,7 +59,7 @@ int main(int argc, char *argv[])
 	struct nl_cli_cls_module *cm;
 	struct rtnl_cls_ops *ops;
 	int err, flags = NLM_F_CREATE | NLM_F_EXCL;
-	char *kind;
+	char *kind, *id = NULL;
  
 	sock = nl_cli_alloc_socket();
 	nl_cli_connect(sock, NETLINK_ROUTE);
@@ -110,7 +110,7 @@ int main(int argc, char *argv[])
 		case 'v': nl_cli_print_version(); break;
 		case 'd': nl_cli_tc_parse_dev(tc, link_cache, optarg); break;
 		case 'p': nl_cli_tc_parse_parent(tc, optarg); break;
-		case 'i': nl_cli_tc_parse_handle(tc, optarg); break;
+		case 'i': id = strdup(optarg); break;
 		case ARG_UPDATE: flags = NLM_F_CREATE; break;
 		case ARG_UPDATE_ONLY: flags = 0; break;
 		case ARG_MTU: nl_cli_tc_parse_mtu(tc, optarg); break;
@@ -133,6 +133,11 @@ int main(int argc, char *argv[])
 	if (!rtnl_tc_get_parent(tc))
 		nl_cli_fatal(EINVAL, "You must specify a parent (--parent=XXX)");
 
+	if (id) {
+		nl_cli_tc_parse_handle(tc, id, 1);
+		free(id);
+	}
+
 	kind = argv[optind++];
 	rtnl_cls_set_kind(cls, kind);
 
diff --git a/src/nl-cls-delete.c b/src/nl-cls-delete.c
index 0ffffb2..359d15e 100644
--- a/src/nl-cls-delete.c
+++ b/src/nl-cls-delete.c
@@ -134,7 +134,7 @@ int main(int argc, char *argv[])
 		case 'v': nl_cli_print_version(); break;
 		case 'd': nl_cli_tc_parse_dev(tc, link_cache, optarg); break;
 		case 'p': nl_cli_tc_parse_parent(tc, optarg); break;
-		case 'i': nl_cli_tc_parse_handle(tc, optarg); break;
+		case 'i': nl_cli_tc_parse_handle(tc, optarg, 0); break;
 		case 'k': nl_cli_cls_parse_kind(cls, optarg); break;
 		case ARG_PROTO: nl_cli_cls_parse_proto(cls, optarg); break;
 		case ARG_PRIO:
diff --git a/src/nl-cls-list.c b/src/nl-cls-list.c
index a0220f8..e7c9a12 100644
--- a/src/nl-cls-list.c
+++ b/src/nl-cls-list.c
@@ -111,7 +111,7 @@ int main(int argc, char *argv[])
 		case 'v': nl_cli_print_version(); break;
 		case 'd': nl_cli_tc_parse_dev(tc, link_cache, optarg); break;
 		case 'p': nl_cli_tc_parse_parent(tc, optarg); break;
-		case 'i': nl_cli_tc_parse_handle(tc, optarg); break;
+		case 'i': nl_cli_tc_parse_handle(tc, optarg, 0); break;
 		case 'k': nl_cli_cls_parse_kind(cls, optarg); break;
 		case ARG_PROTO: nl_cli_cls_parse_proto(cls, optarg); break;
 		case ARG_PRIO:
diff --git a/src/nl-qdisc-add.c b/src/nl-qdisc-add.c
index 57603b0..9da0f18 100644
--- a/src/nl-qdisc-add.c
+++ b/src/nl-qdisc-add.c
@@ -56,7 +56,7 @@ int main(int argc, char *argv[])
 	struct nl_cli_qdisc_module *qm;
 	struct rtnl_qdisc_ops *ops;
 	int err, flags = NLM_F_CREATE | NLM_F_EXCL;
-	char *kind;
+	char *kind, *id = NULL;
  
 	sock = nl_cli_alloc_socket();
 	nl_cli_connect(sock, NETLINK_ROUTE);
@@ -99,7 +99,7 @@ int main(int argc, char *argv[])
 		case 'v': nl_cli_print_version(); break;
 		case 'd': nl_cli_tc_parse_dev(tc, link_cache, optarg); break;
 		case 'p': nl_cli_tc_parse_parent(tc, optarg); break;
-		case 'i': nl_cli_tc_parse_handle(tc, optarg); break;
+		case 'i': id = strdup(optarg); break;
 		case ARG_UPDATE: flags = NLM_F_CREATE; break;
 		case ARG_REPLACE: flags = NLM_F_CREATE | NLM_F_REPLACE; break;
 		case ARG_UPDATE_ONLY: flags = 0; break;
@@ -116,6 +116,11 @@ int main(int argc, char *argv[])
 	if (!rtnl_tc_get_parent(tc))
 		nl_cli_fatal(EINVAL, "You must specify a parent");
 
+	if (id) {
+		nl_cli_tc_parse_handle(tc, id, 1);
+		free(id);
+	}
+
 	kind = argv[optind++];
 	rtnl_qdisc_set_kind(qdisc, kind);
 
diff --git a/src/nl-qdisc-delete.c b/src/nl-qdisc-delete.c
index e91b054..943d5ae 100644
--- a/src/nl-qdisc-delete.c
+++ b/src/nl-qdisc-delete.c
@@ -115,7 +115,7 @@ int main(int argc, char *argv[])
 			break;
 		case 'i':
 			nfilter++;
-			nl_cli_tc_parse_handle(tc, optarg);
+			nl_cli_tc_parse_handle(tc, optarg, 0);
 			break;
 		case 'k':
 			nfilter++;
diff --git a/src/nl-qdisc-list.c b/src/nl-qdisc-list.c
index 1ecb9a4..de24fde 100644
--- a/src/nl-qdisc-list.c
+++ b/src/nl-qdisc-list.c
@@ -85,7 +85,7 @@ int main(int argc, char *argv[])
 		case 'v': nl_cli_print_version(); break;
 		case 'd': nl_cli_tc_parse_dev(tc, link_cache, optarg); break;
 		case 'p': nl_cli_tc_parse_parent(tc, optarg); break;
-		case 'i': nl_cli_tc_parse_handle(tc, optarg); break;
+		case 'i': nl_cli_tc_parse_handle(tc, optarg, 0); break;
 		case 'k': nl_cli_qdisc_parse_kind(qdisc, optarg); break;
 		}
  	}