dns: implement tcp fallback in __res_msend query core

[musl] / src / network / getservbyname_r.c

diff --git a/src/network/getservbyname_r.c b/src/network/getservbyname_r.c
index efa5d91..cad6317 100644 (file)
--- a/src/network/getservbyname_r.c
+++ b/src/network/getservbyname_r.c
@@ -5,41 +5,51 @@
 #include <inttypes.h>
 #include <errno.h>
 #include <string.h>
+#include <stdlib.h>
+#include "lookup.h"
+
+#define ALIGN (sizeof(struct { char a; char *b; }) - sizeof(char *))
 
 int getservbyname_r(const char *name, const char *prots,
        struct servent *se, char *buf, size_t buflen, struct servent **res)
 {
-       struct addrinfo *ai, hint = { .ai_family = AF_INET };
-       int i;
+       struct service servs[MAXSERVS];
+       int cnt, proto, align;
+
+       *res = 0;
 
-       if (!prots) return -(
-               getservbyname_r(name, "tcp", se, buf, buflen, res)
-               && getservbyname_r(name, "udp", se, buf, buflen, res) );
+       /* Don't treat numeric port number strings as service records. */
+       char *end = "";
+       strtoul(name, &end, 10);
+       if (!*end) return ENOENT;
 
        /* Align buffer */
-       i = (uintptr_t)buf & sizeof(char *)-1;
-       if (!i) i = sizeof(char *);
-       if (buflen < 3*sizeof(char *)-i) {
-               errno = ERANGE;
-               return -1;
-       }
-       buf += sizeof(char *)-i;
-       buflen -= sizeof(char *)-i;
+       align = -(uintptr_t)buf & ALIGN-1;
+       if (buflen < 2*sizeof(char *)+align)
+               return ERANGE;
+       buf += align;
 
-       if (!strcmp(prots, "tcp")) hint.ai_protocol = IPPROTO_TCP;
-       else if (!strcmp(prots, "udp")) hint.ai_protocol = IPPROTO_UDP;
-       else return -1;
+       if (!prots) proto = 0;
+       else if (!strcmp(prots, "tcp")) proto = IPPROTO_TCP;
+       else if (!strcmp(prots, "udp")) proto = IPPROTO_UDP;
+       else return EINVAL;
 
-       if (getaddrinfo(0, name, &hint, &ai) < 0) return -1;
+       cnt = __lookup_serv(servs, name, proto, 0, 0);
+       if (cnt<0) switch (cnt) {
+       case EAI_MEMORY:
+       case EAI_SYSTEM:
+               return ENOMEM;
+       default:
+               return ENOENT;
+       }
 
        se->s_name = (char *)name;
        se->s_aliases = (void *)buf;
        se->s_aliases[0] = se->s_name;
        se->s_aliases[1] = 0;
-       se->s_port = ((struct sockaddr_in *)ai->ai_addr)->sin_port;
-       se->s_proto = (char *)prots;
+       se->s_port = htons(servs[0].port);
+       se->s_proto = servs[0].proto == IPPROTO_TCP ? "tcp" : "udp";
 
-       freeaddrinfo(ai);
        *res = se;
        return 0;
 }