When reporting the server as not responding, if the hostname was

supplied, also print the IP address.  This allows IPv4 and IPv6 failures
to be distinguished.  Also useful when a hostname resolves to multiple
IP addresses.

Also, remove use of inet_ntoa() and use our own inet_net_ntop() in all
places, including in libpq, because it is thread-safe.

Author: bmomjian

doc/src/sgml/libpq.sgml

@@ -170,11 +170,11 @@ PGconn *PQconnectdbParams(const char **keywords, const char **values, int expand
            If <literal>host</> is specified without <literal>hostaddr</>,
            a host name lookup occurs.
            If <literal>hostaddr</> is specified without <literal>host</>,
-           the value for <literal>hostaddr</> gives the server address.
+           the value for <literal>hostaddr</> gives the server network address.
            The connection attempt will fail in any of the cases where a
            host name is required.
            If both <literal>host</> and <literal>hostaddr</> are specified,
-           the value for <literal>hostaddr</> gives the server address.
+           the value for <literal>hostaddr</> gives the server network address.
            The value for <literal>host</> is ignored unless needed for
            authentication or verification purposes, in which case it will be
            used as the host name.  Note that authentication is likely to fail

src/backend/utils/adt/Makefile

@@ -23,7 +23,7 @@ OBJS = acl.o arrayfuncs.o array_userfuncs.o arrayutils.o bool.o \
 	oid.o oracle_compat.o pseudotypes.o rowtypes.o \
 	regexp.o regproc.o ruleutils.o selfuncs.o \
 	tid.o timestamp.o varbit.o varchar.o varlena.o version.o xid.o \
-	network.o mac.o inet_net_ntop.o inet_net_pton.o \
+	network.o mac.o inet_cidr_ntop.o inet_net_pton.o \
 	ri_triggers.o pg_lzcompress.o pg_locale.o formatting.o \
 	ascii.o quote.o pgstatfuncs.o encode.o dbsize.o genfile.o trigfuncs.o \
 	tsginidx.o tsgistidx.o tsquery.o tsquery_cleanup.o tsquery_gist.o \

src/backend/utils/adt/inet_net_ntop.c renamed to src/backend/utils/adt/inet_cidr_ntop.c

@@ -32,21 +32,14 @@ static const char rcsid[] = "Id: inet_net_ntop.c,v 1.1.2.2 2004/03/09 09:17:27 m
 #include "utils/inet.h"
 
 
-#define NS_IN6ADDRSZ 16
-#define NS_INT16SZ 2
-
 #ifdef SPRINTF_CHAR
 #define SPRINTF(x) strlen(sprintf/**/x)
 #else
 #define SPRINTF(x) ((size_t)sprintf x)
 #endif
 
-static char *inet_net_ntop_ipv4(const u_char *src, int bits,
-				   char *dst, size_t size);
 static char *inet_cidr_ntop_ipv4(const u_char *src, int bits,
 					char *dst, size_t size);
-static char *inet_net_ntop_ipv6(const u_char *src, int bits,
-				   char *dst, size_t size);
 static char *inet_cidr_ntop_ipv6(const u_char *src, int bits,
 					char *dst, size_t size);
 
@@ -300,231 +293,3 @@ inet_cidr_ntop_ipv6(const u_char *src, int bits, char *dst, size_t size)
 	errno = EMSGSIZE;
 	return (NULL);
 }
-
-
-/*
- * char *
- * inet_net_ntop(af, src, bits, dst, size)
- *	convert host/network address from network to presentation format.
- *	"src"'s size is determined from its "af".
- * return:
- *	pointer to dst, or NULL if an error occurred (check errno).
- * note:
- *	192.5.5.1/28 has a nonzero host part, which means it isn't a network
- *	as called for by inet_net_pton() but it can be a host address with
- *	an included netmask.
- * author:
- *	Paul Vixie (ISC), October 1998
- */
-char *
-inet_net_ntop(int af, const void *src, int bits, char *dst, size_t size)
-{
-	switch (af)
-	{
-		case PGSQL_AF_INET:
-			return (inet_net_ntop_ipv4(src, bits, dst, size));
-		case PGSQL_AF_INET6:
-			return (inet_net_ntop_ipv6(src, bits, dst, size));
-		default:
-			errno = EAFNOSUPPORT;
-			return (NULL);
-	}
-}
-
-/*
- * static char *
- * inet_net_ntop_ipv4(src, bits, dst, size)
- *	convert IPv4 network address from network to presentation format.
- *	"src"'s size is determined from its "af".
- * return:
- *	pointer to dst, or NULL if an error occurred (check errno).
- * note:
- *	network byte order assumed.  this means 192.5.5.240/28 has
- *	0b11110000 in its fourth octet.
- * author:
- *	Paul Vixie (ISC), October 1998
- */
-static char *
-inet_net_ntop_ipv4(const u_char *src, int bits, char *dst, size_t size)
-{
-	char	   *odst = dst;
-	char	   *t;
-	int			len = 4;
-	int			b;
-
-	if (bits < 0 || bits > 32)
-	{
-		errno = EINVAL;
-		return (NULL);
-	}
-
-	/* Always format all four octets, regardless of mask length. */
-	for (b = len; b > 0; b--)
-	{
-		if (size <= sizeof ".255")
-			goto emsgsize;
-		t = dst;
-		if (dst != odst)
-			*dst++ = '.';
-		dst += SPRINTF((dst, "%u", *src++));
-		size -= (size_t) (dst - t);
-	}
-
-	/* don't print masklen if 32 bits */
-	if (bits != 32)
-	{
-		if (size <= sizeof "/32")
-			goto emsgsize;
-		dst += SPRINTF((dst, "/%u", bits));
-	}
-
-	return (odst);
-
-emsgsize:
-	errno = EMSGSIZE;
-	return (NULL);
-}
-
-static int
-decoct(const u_char *src, int bytes, char *dst, size_t size)
-{
-	char	   *odst = dst;
-	char	   *t;
-	int			b;
-
-	for (b = 1; b <= bytes; b++)
-	{
-		if (size <= sizeof "255.")
-			return (0);
-		t = dst;
-		dst += SPRINTF((dst, "%u", *src++));
-		if (b != bytes)
-		{
-			*dst++ = '.';
-			*dst = '\0';
-		}
-		size -= (size_t) (dst - t);
-	}
-	return (dst - odst);
-}
-
-static char *
-inet_net_ntop_ipv6(const u_char *src, int bits, char *dst, size_t size)
-{
-	/*
-	 * Note that int32_t and int16_t need only be "at least" large enough to
-	 * contain a value of the specified size.  On some systems, like Crays,
-	 * there is no such thing as an integer variable with 16 bits. Keep this
-	 * in mind if you think this function should have been coded to use
-	 * pointer overlays.  All the world's not a VAX.
-	 */
-	char		tmp[sizeof "ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255/128"];
-	char	   *tp;
-	struct
-	{
-		int			base,
-					len;
-	}			best, cur;
-	u_int		words[NS_IN6ADDRSZ / NS_INT16SZ];
-	int			i;
-
-	if ((bits < -1) || (bits > 128))
-	{
-		errno = EINVAL;
-		return (NULL);
-	}
-
-	/*
-	 * Preprocess: Copy the input (bytewise) array into a wordwise array. Find
-	 * the longest run of 0x00's in src[] for :: shorthanding.
-	 */
-	memset(words, '\0', sizeof words);
-	for (i = 0; i < NS_IN6ADDRSZ; i++)
-		words[i / 2] |= (src[i] << ((1 - (i % 2)) << 3));
-	best.base = -1;
-	cur.base = -1;
-	best.len = 0;
-	cur.len = 0;
-	for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++)
-	{
-		if (words[i] == 0)
-		{
-			if (cur.base == -1)
-				cur.base = i, cur.len = 1;
-			else
-				cur.len++;
-		}
-		else
-		{
-			if (cur.base != -1)
-			{
-				if (best.base == -1 || cur.len > best.len)
-					best = cur;
-				cur.base = -1;
-			}
-		}
-	}
-	if (cur.base != -1)
-	{
-		if (best.base == -1 || cur.len > best.len)
-			best = cur;
-	}
-	if (best.base != -1 && best.len < 2)
-		best.base = -1;
-
-	/*
-	 * Format the result.
-	 */
-	tp = tmp;
-	for (i = 0; i < (NS_IN6ADDRSZ / NS_INT16SZ); i++)
-	{
-		/* Are we inside the best run of 0x00's? */
-		if (best.base != -1 && i >= best.base &&
-			i < (best.base + best.len))
-		{
-			if (i == best.base)
-				*tp++ = ':';
-			continue;
-		}
-		/* Are we following an initial run of 0x00s or any real hex? */
-		if (i != 0)
-			*tp++ = ':';
-		/* Is this address an encapsulated IPv4? */
-		if (i == 6 && best.base == 0 && (best.len == 6 ||
-									 (best.len == 7 && words[7] != 0x0001) ||
-									  (best.len == 5 && words[5] == 0xffff)))
-		{
-			int			n;
-
-			n = decoct(src + 12, 4, tp, sizeof tmp - (tp - tmp));
-			if (n == 0)
-			{
-				errno = EMSGSIZE;
-				return (NULL);
-			}
-			tp += strlen(tp);
-			break;
-		}
-		tp += SPRINTF((tp, "%x", words[i]));
-	}
-
-	/* Was it a trailing run of 0x00's? */
-	if (best.base != -1 && (best.base + best.len) ==
-		(NS_IN6ADDRSZ / NS_INT16SZ))
-		*tp++ = ':';
-	*tp = '\0';
-
-	if (bits != -1 && bits != 128)
-		tp += SPRINTF((tp, "/%u", bits));
-
-	/*
-	 * Check for overflow, copy, and we're done.
-	 */
-	if ((size_t) (tp - tmp) > size)
-	{
-		errno = EMSGSIZE;
-		return (NULL);
-	}
-	strcpy(dst, tmp);
-	return (dst);
-}

src/include/port.h

@@ -437,4 +437,8 @@ extern void qsort_arg(void *base, size_t nel, size_t elsize,
 /* port/chklocale.c */
 extern int	pg_get_encoding_from_locale(const char *ctype);
 
+/* port/inet_net_ntop.c */
+extern char *inet_net_ntop(int af, const void *src, int bits,
+			  char *dst, size_t size);
+
 #endif   /* PG_PORT_H */

src/include/utils/builtins.h

@@ -795,9 +795,7 @@ extern Datum chr (PG_FUNCTION_ARGS);
 extern Datum repeat(PG_FUNCTION_ARGS);
 extern Datum ascii(PG_FUNCTION_ARGS);
 
-/* inet_net_ntop.c */
-extern char *inet_net_ntop(int af, const void *src, int bits,
-			  char *dst, size_t size);
+/* inet_cidr_ntop.c */
 extern char *inet_cidr_ntop(int af, const void *src, int bits,
 			   char *dst, size_t size);
 

src/interfaces/libpq/fe-connect.c

@@ -960,16 +960,39 @@ connectFailureMessage(PGconn *conn, int errorno)
 	else
 #endif   /* HAVE_UNIX_SOCKETS */
 	{
+		char	host_addr[NI_MAXHOST];
+		bool 	display_host_addr;
+		struct sockaddr_in *host_addr_struct = (struct sockaddr_in *)
+												&conn->raddr.addr;
+
+		/*
+		 *	Optionally display the network address with the hostname.
+		 *	This is useful to distinguish between IPv4 and IPv6 connections.
+		 */
+		if (conn->pghostaddr != NULL)
+			strlcpy(host_addr, conn->pghostaddr, NI_MAXHOST);
+		else if (inet_net_ntop(conn->addr_cur->ai_family, &host_addr_struct->sin_addr,
+				 host_addr_struct->sin_family == AF_INET ? 32 : 128,
+				 host_addr, sizeof(host_addr)) == NULL)
+			strcpy(host_addr, "???");
+
+		display_host_addr = !conn->pghostaddr &&
+							strcmp(conn->pghost, host_addr) != 0;
+		
 		appendPQExpBuffer(&conn->errorMessage,
 						  libpq_gettext("could not connect to server: %s\n"
-					 "\tIs the server running on host \"%s\" and accepting\n"
+					 "\tIs the server running on host \"%s\" %s%s%sand accepting\n"
 										"\tTCP/IP connections on port %s?\n"),
 						  SOCK_STRERROR(errorno, sebuf, sizeof(sebuf)),
 						  conn->pghostaddr
 						  ? conn->pghostaddr
 						  : (conn->pghost
 							 ? conn->pghost
 							 : "???"),
+						  /* display the IP address only if not already output */
+						  display_host_addr ? "(" : "",
+						  display_host_addr ? host_addr : "",
+						  display_host_addr ? ") " : "",
 						  conn->pgport);
 	}
 }

src/port/Makefile

@@ -30,7 +30,7 @@ include $(top_builddir)/src/Makefile.global
 override CPPFLAGS := -I$(top_builddir)/src/port -DFRONTEND $(CPPFLAGS)
 LIBS += $(PTHREAD_LIBS)
 
-OBJS = $(LIBOBJS) chklocale.o dirmod.o exec.o noblock.o path.o \
+OBJS = $(LIBOBJS) chklocale.o dirmod.o exec.o inet_net_ntop.o noblock.o path.o \
 	pgsleep.o pgstrcasecmp.o qsort.o qsort_arg.o sprompt.o thread.o
 ifneq (,$(filter $(PORTNAME),cygwin win32))
 OBJS += pipe.o

src/port/getaddrinfo.c

@@ -388,16 +388,14 @@ getnameinfo(const struct sockaddr * sa, int salen,
 
 	if (node)
 	{
-		int			ret = -1;
-
 		if (sa->sa_family == AF_INET)
 		{
-			char	   *p;
-
-			p = inet_ntoa(((struct sockaddr_in *) sa)->sin_addr);
-			ret = snprintf(node, nodelen, "%s", p);
+			if (inet_net_ntop(AF_INET, ((struct sockaddr_in *) sa)->sin_addr,
+				sa->sa_family == AF_INET ? 32 : 128,
+				node, nodelen) == NULL)
+			return EAI_MEMORY;
 		}
-		if (ret == -1 || ret > nodelen)
+		else
 			return EAI_MEMORY;
 	}