getaddrinfo.c: improve code readability. No functional changes

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>

libc/inet/getaddrinfo.c

@@ -395,9 +395,9 @@ gaih_inet(const char *name, const struct gaih_service *service,
 {
 	struct gaih_servtuple nullserv;
 
-	const struct gaih_typeproto *tp = gaih_inet_typeproto;
-	struct gaih_servtuple *st = &nullserv;
-	struct gaih_addrtuple *at = NULL;
+	const struct gaih_typeproto *tp;
+	struct gaih_servtuple *st;
+	struct gaih_addrtuple *at;
 	int rc;
 	int v4mapped = (req->ai_family == PF_UNSPEC || req->ai_family == PF_INET6)
 			&& (req->ai_flags & AI_V4MAPPED);
@@ -405,22 +405,24 @@ gaih_inet(const char *name, const struct gaih_service *service,
 
 	memset(&nullserv, 0, sizeof(nullserv));
 
+	tp = gaih_inet_typeproto;
 	if (req->ai_protocol || req->ai_socktype) {
 		++tp;
-		while (tp->name[0]
-			&& ((req->ai_socktype != 0 && req->ai_socktype != tp->socktype)
-			    || (req->ai_protocol != 0 && !(tp->protoflag & GAI_PROTO_PROTOANY) && req->ai_protocol != tp->protocol)
-			)
-		) {
+		while (tp->name[0]) {
+			if ((req->ai_socktype == 0 || req->ai_socktype == tp->socktype)
+			 && (req->ai_protocol == 0 || req->ai_protocol == tp->protocol || (tp->protoflag & GAI_PROTO_PROTOANY))
+			) {
+				goto found;
+			}
 			++tp;
 		}
-		if (! tp->name[0]) {
-			if (req->ai_socktype)
-				return (GAIH_OKIFUNSPEC | -EAI_SOCKTYPE);
-			return (GAIH_OKIFUNSPEC | -EAI_SERVICE);
-		}
+		if (req->ai_socktype)
+			return (GAIH_OKIFUNSPEC | -EAI_SOCKTYPE);
+		return (GAIH_OKIFUNSPEC | -EAI_SERVICE);
+ found: ;
 	}
 
+	st = &nullserv;
 	if (service != NULL) {
 		if ((tp->protoflag & GAI_PROTO_NOSERVICE) != 0)
 			return (GAIH_OKIFUNSPEC | -EAI_SERVICE);
@@ -495,6 +497,7 @@ gaih_inet(const char *name, const struct gaih_service *service,
 		}
 	}
 
+	at = NULL;
 	if (name != NULL) {
 		at = alloca(sizeof(struct gaih_addrtuple));
 		at->family = AF_UNSPEC;
@@ -502,10 +505,9 @@ gaih_inet(const char *name, const struct gaih_service *service,
 		at->next = NULL;
 
 		if (inet_pton(AF_INET, name, at->addr) > 0) {
-			if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET || v4mapped)
-				at->family = AF_INET;
-			else
+			if (req->ai_family != AF_UNSPEC && req->ai_family != AF_INET && !v4mapped)
 				return -EAI_FAMILY;
+			at->family = AF_INET;
 		}
 
 #if defined __UCLIBC_HAS_IPV6__
@@ -518,11 +520,9 @@ gaih_inet(const char *name, const struct gaih_service *service,
 				*scope_delim = '\0';
 
 			if (inet_pton(AF_INET6, namebuf, at->addr) > 0) {
-				if (req->ai_family == AF_UNSPEC || req->ai_family == AF_INET6)
-					at->family = AF_INET6;
-				else
+				if (req->ai_family != AF_UNSPEC && req->ai_family != AF_INET6)
 					return -EAI_FAMILY;
-
+				at->family = AF_INET6;
 				if (scope_delim != NULL) {
 					int try_numericscope = 0;
 					uint32_t *a32 = (uint32_t*)at->addr;
@@ -545,7 +545,7 @@ gaih_inet(const char *name, const struct gaih_service *service,
 		}
 #endif
 
-		if (at->family == AF_UNSPEC && (req->ai_flags & AI_NUMERICHOST) == 0) {
+		if (at->family == AF_UNSPEC && !(req->ai_flags & AI_NUMERICHOST)) {
 			struct hostent *h;
 			struct gaih_addrtuple **pat = &at;
 			int no_data = 0;
@@ -783,9 +783,9 @@ int
 getaddrinfo(const char *name, const char *service,
 	     const struct addrinfo *hints, struct addrinfo **pai)
 {
-	int i = 0, j, last_i = 0;
-	struct addrinfo *p = NULL, **end;
-	const struct gaih *g = gaih, *pg = NULL;
+	int i, j, last_i;
+	struct addrinfo *p, **end;
+	const struct gaih *g, *pg;
 	struct gaih_service gaih_service, *pservice;
 	struct addrinfo default_hints;
 
@@ -800,7 +800,7 @@ getaddrinfo(const char *name, const char *service,
 
 	if (hints == NULL) {
 		memset(&default_hints, 0, sizeof(default_hints));
-		if (AF_UNSPEC)
+		if (AF_UNSPEC != 0)
 			default_hints.ai_family = AF_UNSPEC;
 		hints = &default_hints;
 	}
@@ -832,10 +832,14 @@ getaddrinfo(const char *name, const char *service,
 	} else
 		pservice = NULL;
 
+	g = gaih;
+	pg = NULL;
+	p = NULL;
 	end = NULL;
 	if (pai)
 		end = &p;
-
+	i = 0;
+	last_i = 0;
 	j = 0;
 	while (g->gaih) {
 		if (hints->ai_family == g->family || hints->ai_family == AF_UNSPEC) {