Implement dynamic option numbering.

This permits option numbers to be allocated based on string name.
Eventually all the option values will be replaced with option
names.  This will facilitate transports (ZeroTier) that may need
further options.

1 files changed, 157 insertions, 0 deletions

diff --git a/src/core/options.c b/src/core/options.c
index ecfa437e..55797218 100644
--- a/src/core/options.c
+++ b/src/core/options.c
@@ -10,8 +10,22 @@
 
 #include "core/nng_impl.h"
 
+#include <stdio.h>
 #include <string.h>
 
+// Dynamic options.
+
+typedef struct nni_option nni_option;
+struct nni_option {
+	nni_list_node o_link;
+	char *        o_name;
+	int           o_id;
+};
+
+static nni_mtx  nni_option_lk;
+static nni_list nni_options;
+static int      nni_option_nextid;
+
 int
 nni_chkopt_usec(const void *v, size_t sz)
 {
@@ -241,3 +255,146 @@ nni_getopt_fd(nni_sock *s, nni_notifyfd *fd, int mask, void *val, size_t *szp)
 	memcpy(val, &fd->sn_rfd, sizeof(int));
 	return (0);
 }
+
+// nni_option_set_id sets the id for an option, if not already done so.
+// (Some options have hard coded values that end-user may depend upon.)
+// If the ID passed in is negative, then a new ID is allocated dynamically.
+static int
+nni_option_set_id(const char *name, int id)
+{
+	nni_option *opt;
+	int         len;
+	nni_mtx_lock(&nni_option_lk);
+	NNI_LIST_FOREACH (&nni_options, opt) {
+		if (strcmp(name, opt->o_name) == 0) {
+			nni_mtx_unlock(&nni_option_lk);
+			return (0);
+		}
+	}
+	if ((opt = NNI_ALLOC_STRUCT(opt)) == NULL) {
+		nni_mtx_unlock(&nni_option_lk);
+		return (NNG_ENOMEM);
+	}
+	len = strlen(name) + 1;
+	if ((opt->o_name = nni_alloc(len)) == NULL) {
+		nni_mtx_unlock(&nni_option_lk);
+		NNI_FREE_STRUCT(opt);
+		return (NNG_ENOMEM);
+	}
+	(void) snprintf(opt->o_name, len, "%s", name);
+	if (id < 0) {
+		id = nni_option_nextid++;
+	}
+	opt->o_id = id;
+	nni_list_append(&nni_options, opt);
+	nni_mtx_unlock(&nni_option_lk);
+	return (0);
+}
+
+int
+nni_option_lookup(const char *name)
+{
+	nni_option *opt;
+	int         id = -1;
+
+	nni_mtx_lock(&nni_option_lk);
+	NNI_LIST_FOREACH (&nni_options, opt) {
+		if (strcmp(name, opt->o_name) == 0) {
+			id = opt->o_id;
+			break;
+		}
+	}
+	nni_mtx_unlock(&nni_option_lk);
+	return (id);
+}
+
+const char *
+nni_option_name(int id)
+{
+	nni_option *opt;
+	const char *name = NULL;
+
+	nni_mtx_lock(&nni_option_lk);
+	NNI_LIST_FOREACH (&nni_options, opt) {
+		if (id == opt->o_id) {
+			name = opt->o_name;
+			break;
+		}
+	}
+	nni_mtx_unlock(&nni_option_lk);
+	return (name);
+}
+
+int
+nni_option_register(const char *name, int *idp)
+{
+	int id;
+	int rv;
+
+	// Note that if the id was already in use, we will
+	// wind up leaving a gap in the ID space.  That should
+	// be inconsequential.
+	if ((rv = nni_option_set_id(name, -1)) != 0) {
+		return (rv);
+	}
+	*idp = nni_option_lookup(name);
+	return (0);
+}
+
+int
+nni_option_sys_init(void)
+{
+	nni_mtx_init(&nni_option_lk);
+	NNI_LIST_INIT(&nni_options, nni_option, o_link);
+	nni_option_nextid = 0x10000;
+	int rv;
+
+	// Register our well-known options.
+	if (((rv = nni_option_set_id("raw", NNG_OPT_RAW)) != 0) ||
+	    ((rv = nni_option_set_id("linger", NNG_OPT_LINGER)) != 0) ||
+	    ((rv = nni_option_set_id("recv-buf", NNG_OPT_RCVBUF)) != 0) ||
+	    ((rv = nni_option_set_id("send-buf", NNG_OPT_SNDBUF)) != 0) ||
+	    ((rv = nni_option_set_id("recv-timeout", NNG_OPT_RCVTIMEO)) !=
+	        0) ||
+	    ((rv = nni_option_set_id("send-timeout", NNG_OPT_SNDTIMEO)) !=
+	        0) ||
+	    ((rv = nni_option_set_id("reconnect-time", NNG_OPT_RECONN_TIME)) !=
+	        0) ||
+	    ((rv = nni_option_set_id(
+	          "reconnect-max-time", NNG_OPT_RECONN_MAXTIME)) != 0) ||
+	    ((rv = nni_option_set_id("recv-max-size", NNG_OPT_RCVMAXSZ)) !=
+	        0) ||
+	    ((rv = nni_option_set_id("max-ttl", NNG_OPT_MAXTTL)) != 0) ||
+	    ((rv = nni_option_set_id("protocol", NNG_OPT_PROTOCOL)) != 0) ||
+	    ((rv = nni_option_set_id("subscribe", NNG_OPT_SUBSCRIBE)) != 0) ||
+	    ((rv = nni_option_set_id("unsubscribe", NNG_OPT_UNSUBSCRIBE)) !=
+	        0) ||
+	    ((rv = nni_option_set_id("survey-time", NNG_OPT_SURVEYTIME)) !=
+	        0) ||
+	    ((rv = nni_option_set_id("resend-time", NNG_OPT_RESENDTIME)) !=
+	        0) ||
+	    ((rv = nni_option_set_id("transport", NNG_OPT_TRANSPORT)) != 0) ||
+	    ((rv = nni_option_set_id("local-addr", NNG_OPT_LOCALADDR)) != 0) ||
+	    ((rv = nni_option_set_id("remote-addr", NNG_OPT_REMOTEADDR)) !=
+	        0) ||
+	    ((rv = nni_option_set_id("recv-fd", NNG_OPT_RCVFD)) != 0) ||
+	    ((rv = nni_option_set_id("send-fd", NNG_OPT_SNDFD)) != 0)) {
+		nni_option_sys_fini();
+		return (rv);
+	}
+	return (0);
+}
+
+void
+nni_option_sys_fini(void)
+{
+	if (nni_option_nextid != 0) {
+		nni_option *opt;
+		while ((opt = nni_list_first(&nni_options)) != NULL) {
+			nni_list_remove(&nni_options, opt);
+			nni_free(opt->o_name, strlen(opt->o_name) + 1);
+			NNI_FREE_STRUCT(opt);
+		}
+	}
+	nni_option_nextid = 0;
+}
\ No newline at end of file