This is a series of diffs that cleans up of we use getaddrinfo(), how we
reach into struct sockaddr_storage and also in preparation for future
semplifications.  For the moment I'm happy to delete got_sockaddr.[ch],
but that's a followup, this and another step needs to be taken before.

I prefer to split these steps into a few more manegeable diffs since it's
a bit intricate the relations between the various parts.

This merges get_addrs() and host() and slightly improves our
getaddrinfo() usage.  We currently use getaddrinfo() to resolve
hostnames and ip addresses but not services/port names, and then reach
into the struct storage.  Instead:

 - pass the hostname or NULL when we want to listen on everything

   before we used "" to represent any address (see the deleted chunk at
   the end).  Here, I've changed the syntax of the config file use *
   instead (only real change in the series of diffs).  I'm not sure how
   useful is to listen on any address, but that was the previous
   behaviour and I kept it.  Happy to drop it in a follow-up.

 - set AI_PASSIVE

   needed since we later want to use the return for bind()

 - pass the portname too

   so that we don't need to reach into the struct sockaddr_storage, but
   this will be exploited in a future diff.  For the moment, I'm only
   re-converting the port number to a string and passing that.  Further
   cleanup will be done as follow-up.

 - removed GOTWEBD_MAXIFACE since it was only used in host().

ok?

diff /home/op/w/gotwebd
commit - af09dd3fec1090c7273f680a0ae5bf50d2183390
path + /home/op/w/gotwebd
blob - 1ea7f7b6e6083db17472436ab39cbdb63fb3dc1f
file + gotwebd/gotwebd.h
--- gotwebd/gotwebd.h
+++ gotwebd/gotwebd.h
@@ -47,7 +47,6 @@
 #define GOTWEBD_MAXNAME		 64
 #define GOTWEBD_MAXPORT		 6
 #define GOTWEBD_NUMPROC		 3
-#define GOTWEBD_MAXIFACE	 16
 #define GOTWEBD_REPO_CACHESIZE	 4
 
 /* GOTWEB DEFAULTS */
blob - 300d47b9f6f477f3d3c2f3f874ceb2d817ce2425
file + gotwebd/parse.y
--- gotwebd/parse.y
+++ gotwebd/parse.y
@@ -99,8 +99,6 @@ int		 get_addrs(const char *, struct server *, in_port
 int		 addr_dup_check(struct addresslist *, struct address *,
 		    const char *, const char *);
 int		 add_addr(struct server *, struct address *);
-int		 host(const char *, struct server *,
-		    int, in_port_t, const char *);
 
 typedef struct {
 	union {
@@ -123,6 +121,7 @@ typedef struct {
 %type	<v.port>	fcgiport
 %token	<v.number>	NUMBER
 %type	<v.number>	boolean
+%type	<v.string>	listen_addr
 
 %%
 
@@ -176,6 +175,10 @@ boolean		: STRING {
 		}
 		;
 
+listen_addr	: '*' { $$ = NULL; }
+		| STRING
+		;
+
 fcgiport	: PORT NUMBER {
 			if ($2 <= 0 || $2 > (int)USHRT_MAX) {
 				yyerror("invalid port: %lld", $2);
@@ -342,7 +345,7 @@ serveropts1	: REPOS_PATH STRING {
 			}
 			free($2);
 		}
-		| LISTEN ON STRING fcgiport {
+		| LISTEN ON listen_addr fcgiport {
 			if (get_addrs($3, new_srv, $4) == -1) {
 				yyerror("could not get addrs");
 				YYERROR;
@@ -1020,39 +1023,40 @@ getservice(const char *n)
 }
 
 int
-host(const char *s, struct server *new_srv, int max,
-    in_port_t port, const char *ifname)
+get_addrs(const char *s, struct server *new_srv, in_port_t port)
 {
 	struct addrinfo hints, *res0, *res;
-	int error, cnt = 0;
+	int n, error;
 	struct sockaddr_in *sain;
 	struct sockaddr_in6 *sin6;
 	struct address *h;
+	char portstr[32];
 
+	n = snprintf(portstr, sizeof(portstr), "%d", port);
+	if (n < 0 || (size_t)n >= sizeof(portstr))
+		fatalx("snprintf: number too long");
+
 	memset(&hints, 0, sizeof(hints));
 	hints.ai_family = AF_UNSPEC;
 	hints.ai_socktype = SOCK_STREAM; /* DUMMY */
-	hints.ai_flags = AI_ADDRCONFIG;
-	error = getaddrinfo(s, NULL, &hints, &res0);
-	if (error == EAI_AGAIN || error == EAI_NODATA || error == EAI_NONAME)
-		return (0);
+	hints.ai_flags = AI_PASSIVE | AI_ADDRCONFIG;
+	error = getaddrinfo(s, portstr, &hints, &res0);
 	if (error) {
 		log_warnx("%s: could not parse \"%s\": %s", __func__, s,
 		    gai_strerror(error));
 		return (-1);
 	}
 
-	for (res = res0; res && cnt < max; res = res->ai_next) {
-		if (res->ai_family != AF_INET &&
-		    res->ai_family != AF_INET6)
-			continue;
+	for (res = res0; res; res = res->ai_next) {
 		if ((h = calloc(1, sizeof(*h))) == NULL)
 			fatal(__func__);
 
 		if (port)
 			h->port = port;
-		if (ifname != NULL) {
-			if (strlcpy(h->ifname, ifname, sizeof(h->ifname)) >=
+		if (s == NULL) {
+			strlcpy(h->ifname, "*", sizeof(h->ifname));
+		} else {
+			if (strlcpy(h->ifname, s, sizeof(h->ifname)) >=
 			    sizeof(h->ifname)) {
 				log_warnx("%s: interface name truncated",
 				    __func__);
@@ -1077,35 +1081,8 @@ host(const char *s, struct server *new_srv, int max,
 
 		if (add_addr(new_srv, h))
 			return -1;
-		cnt++;
 	}
-	if (cnt == max && res) {
-		log_warnx("%s: %s resolves to more than %d hosts", __func__,
-		    s, max);
-	}
 	freeaddrinfo(res0);
-	return (cnt);
-}
-
-int
-get_addrs(const char *addr, struct server *new_srv, in_port_t port)
-{
-	if (strcmp("", addr) == 0) {
-		if (host("127.0.0.1", new_srv, 1, port, "127.0.0.1") <= 0) {
-			yyerror("invalid listen ip: %s",
-			    "127.0.0.1");
-			return (-1);
-		}
-		if (host("::1", new_srv, 1, port, "::1") <= 0) {
-			yyerror("invalid listen ip: %s", "::1");
-			return (-1);
-		}
-	} else {
-		if (host(addr, new_srv, GOTWEBD_MAXIFACE, port, addr) <= 0) {
-			yyerror("invalid listen ip: %s", addr);
-			return (-1);
-		}
-	}
 	return (0);
 }