[glibc/siddhesh/gai-cleanup2] gaih_inet: Split addrinfo result generation into its own function

[glibc/siddhesh/gai-cleanup2] gaih_inet: Split addrinfo result generation into its own function

[Siddhesh Poyarekar]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=e9942569d128646a2ab19128bf3b01801e22e207

commit e9942569d128646a2ab19128bf3b01801e22e207
Author: Siddhesh Poyarekar <siddhesh@sourceware.org>
Date:   Mon Feb 28 23:30:43 2022 +0530

    gaih_inet: Split addrinfo result generation into its own function
    
    Signed-off-by: Siddhesh Poyarekar <siddhesh@sourceware.org>

Diff:
---
 sysdeps/posix/getaddrinfo.c | 174 ++++++++++++++++++++++----------------------
 1 file changed, 89 insertions(+), 85 deletions(-)

diff --git a/sysdeps/posix/getaddrinfo.c b/sysdeps/posix/getaddrinfo.c
index 89bca7795a..036a9539b0 100644
--- a/sysdeps/posix/getaddrinfo.c
+++ b/sysdeps/posix/getaddrinfo.c
@@ -1116,6 +1116,89 @@ process_canonname (const struct addrinfo *req, const char *orig_name,
   return 0;
 }
 
+static int
+generate_addrinfo (const char *canon, const struct addrinfo *req,
+		   const struct gaih_lookup_result *res,
+		   const struct gaih_servtuple *st,
+		   struct addrinfo **pai, unsigned int *naddrs)
+{
+  size_t socklen;
+  sa_family_t family;
+
+  /* Buffer is the size of an unformatted IPv6 address in printable
+     format.  */
+  for (struct gaih_addrtuple *at2 = res->at; at2 != NULL; at2 = at2->next)
+    {
+      family = at2->family;
+      if (family == AF_INET6)
+	{
+	  socklen = sizeof (struct sockaddr_in6);
+
+	  /* If we looked up IPv4 mapped address discard them here if
+	     the caller isn't interested in all address and we have
+	     found at least one IPv6 address.  */
+	  if (res->got_ipv6
+	      && (req->ai_flags & (AI_V4MAPPED|AI_ALL)) == AI_V4MAPPED
+	      && IN6_IS_ADDR_V4MAPPED (at2->addr))
+	    continue;
+	}
+      else
+	socklen = sizeof (struct sockaddr_in);
+
+      for (int i = 0; st[i].set; i++)
+	{
+	  struct addrinfo *ai;
+	  ai = *pai = malloc (sizeof (struct addrinfo) + socklen);
+	  if (ai == NULL)
+	    return -EAI_MEMORY;
+
+	  ai->ai_flags = req->ai_flags;
+	  ai->ai_family = family;
+	  ai->ai_socktype = st[i].socktype;
+	  ai->ai_protocol = st[i].protocol;
+	  ai->ai_addrlen = socklen;
+	  ai->ai_addr = (void *) (ai + 1);
+
+	  /* We only add the canonical name once.  */
+	  ai->ai_canonname = (char *) canon;
+	  canon = NULL;
+
+#ifdef _HAVE_SA_LEN
+	  ai->ai_addr->sa_len = socklen;
+#endif /* _HAVE_SA_LEN */
+	  ai->ai_addr->sa_family = family;
+
+	  /* In case of an allocation error the list must be NULL
+	     terminated.  */
+	  ai->ai_next = NULL;
+
+	  if (family == AF_INET6)
+	    {
+	      struct sockaddr_in6 *sin6p =
+		(struct sockaddr_in6 *) ai->ai_addr;
+
+	      sin6p->sin6_port = st[i].port;
+	      sin6p->sin6_flowinfo = 0;
+	      memcpy (&sin6p->sin6_addr,
+		      at2->addr, sizeof (struct in6_addr));
+	      sin6p->sin6_scope_id = at2->scopeid;
+	    }
+	  else
+	    {
+	      struct sockaddr_in *sinp = (struct sockaddr_in *) ai->ai_addr;
+	      sinp->sin_port = st[i].port;
+	      memcpy (&sinp->sin_addr, at2->addr, sizeof (struct in_addr));
+	      memset (sinp->sin_zero, '\0', sizeof (sinp->sin_zero));
+	    }
+
+	  pai = &(ai->ai_next);
+	}
+
+      ++*naddrs;
+    }
+  return 0;
+}
+
 static int
 gaih_inet (const char *name, const struct gaih_service *service,
 	   const struct addrinfo *req, struct addrinfo **pai,
@@ -1202,96 +1285,17 @@ gaih_inet (const char *name, const struct gaih_service *service,
     }
 
 process_list:
-  {
-    /* Set up the canonical name if we need it.  */
-    if ((result = process_canonname (req, orig_name, &canon)) != 0)
-      goto free_and_return;
+  /* Set up the canonical name if we need it.  */
+  if ((result = process_canonname (req, orig_name, &canon)) != 0)
+    goto free_and_return;
 
-    size_t socklen;
-    sa_family_t family;
-
-    /* Buffer is the size of an unformatted IPv6 address in printable
-       format.  */
-    for (struct gaih_addrtuple *at2 = res.at; at2 != NULL; at2 = at2->next)
-      {
-	family = at2->family;
-	if (family == AF_INET6)
-	  {
-	    socklen = sizeof (struct sockaddr_in6);
-
-	    /* If we looked up IPv4 mapped address discard them here if
-	       the caller isn't interested in all address and we have
-	       found at least one IPv6 address.  */
-	    if (res.got_ipv6
-		&& (req->ai_flags & (AI_V4MAPPED|AI_ALL)) == AI_V4MAPPED
-		&& IN6_IS_ADDR_V4MAPPED (at2->addr))
-	      continue;
-	  }
-	else
-	  socklen = sizeof (struct sockaddr_in);
-
-	for (int i = 0; st[i].set; i++)
-	  {
-	    struct addrinfo *ai;
-	    ai = *pai = malloc (sizeof (struct addrinfo) + socklen);
-	    if (ai == NULL)
-	      {
-		result = -EAI_MEMORY;
-		goto free_and_return;
-	      }
-
-	    ai->ai_flags = req->ai_flags;
-	    ai->ai_family = family;
-	    ai->ai_socktype = st[i].socktype;
-	    ai->ai_protocol = st[i].protocol;
-	    ai->ai_addrlen = socklen;
-	    ai->ai_addr = (void *) (ai + 1);
-
-	    /* We only add the canonical name once.  */
-	    ai->ai_canonname = (char *) canon;
-	    canon = NULL;
-
-#ifdef _HAVE_SA_LEN
-	    ai->ai_addr->sa_len = socklen;
-#endif /* _HAVE_SA_LEN */
-	    ai->ai_addr->sa_family = family;
-
-	    /* In case of an allocation error the list must be NULL
-	       terminated.  */
-	    ai->ai_next = NULL;
-
-	    if (family == AF_INET6)
-	      {
-		struct sockaddr_in6 *sin6p =
-		  (struct sockaddr_in6 *) ai->ai_addr;
-
-		sin6p->sin6_port = st[i].port;
-		sin6p->sin6_flowinfo = 0;
-		memcpy (&sin6p->sin6_addr,
-			at2->addr, sizeof (struct in6_addr));
-		sin6p->sin6_scope_id = at2->scopeid;
-	      }
-	    else
-	      {
-		struct sockaddr_in *sinp =
-		  (struct sockaddr_in *) ai->ai_addr;
-		sinp->sin_port = st[i].port;
-		memcpy (&sinp->sin_addr,
-			at2->addr, sizeof (struct in_addr));
-		memset (sinp->sin_zero, '\0', sizeof (sinp->sin_zero));
-	      }
-
-	    pai = &(ai->ai_next);
-	  }
-
-	++*naddrs;
-      }
-  }
+  result = generate_addrinfo (canon, req, &res, st, pai, naddrs);
 
  free_and_return:
   if (malloc_name)
     free ((char *) name);
-  free (canon);
+  if (result != 0)
+    free (canon);
   gaih_lookup_result_free (&res);
   scratch_buffer_free (&resbuf);