Avoid conflicts with library versions of inet_net_ntop() and friends.

Prefix inet_net_ntop and sibling routines with "pg_" to ensure that
they aren't mistaken for C-library functions.  This fixes warnings
from cpluspluscheck on some platforms, and should help reduce reader
confusion everywhere, since our functions aren't exactly interchangeable
with the library versions (they may have different ideas about address
family codes).

This shouldn't be fixing any actual bugs, unless somebody's linker
is misbehaving, so no need to back-patch.

Discussion: https://postgr.es/m/20518.1559494394@sss.pgh.pa.us

src/backend/utils/adt/inet_cidr_ntop.c

@@ -44,7 +44,7 @@ static char *inet_cidr_ntop_ipv6(const u_char *src, int bits,
 
 /*
  * char *
- * inet_cidr_ntop(af, src, bits, dst, size)
+ * pg_inet_cidr_ntop(af, src, bits, dst, size)
  *	convert network number from network to presentation format.
  *	generates CIDR style result always.
  * return:
@@ -53,7 +53,7 @@ static char *inet_cidr_ntop_ipv6(const u_char *src, int bits,
  *	Paul Vixie (ISC), July 1996
  */
 char *
-inet_cidr_ntop(int af, const void *src, int bits, char *dst, size_t size)
+pg_inet_cidr_ntop(int af, const void *src, int bits, char *dst, size_t size)
 {
 	switch (af)
 	{

src/backend/utils/adt/inet_net_pton.c

@@ -42,7 +42,7 @@ static int	inet_cidr_pton_ipv6(const char *src, u_char *dst, size_t size);
 
 /*
  * int
- * inet_net_pton(af, src, dst, size)
+ * pg_inet_net_pton(af, src, dst, size)
  *	convert network number from presentation to network format.
  *	accepts hex octets, hex strings, decimal octets, and /CIDR.
  *	"size" is in bytes and describes "dst".
@@ -59,7 +59,7 @@ static int	inet_cidr_pton_ipv6(const char *src, u_char *dst, size_t size);
  *
  */
 int
-inet_net_pton(int af, const char *src, void *dst, size_t size)
+pg_inet_net_pton(int af, const char *src, void *dst, size_t size)
 {
 	switch (af)
 	{
@@ -241,7 +241,7 @@ emsgsize:
 
 /*
  * int
- * inet_net_pton(af, src, dst, *bits)
+ * inet_net_pton_ipv4(af, src, dst, *bits)
  *	convert network address from presentation to network format.
  *	accepts inet_pton()'s input for this "af" plus trailing "/CIDR".
  *	"dst" is assumed large enough for its "af".  "bits" is set to the

src/backend/utils/adt/network.c

@@ -91,7 +91,7 @@ network_in(char *src, bool is_cidr)
 	else
 		ip_family(dst) = PGSQL_AF_INET;
 
-	bits = inet_net_pton(ip_family(dst), src, ip_addr(dst),
+	bits = pg_inet_net_pton(ip_family(dst), src, ip_addr(dst),
 							is_cidr ? ip_addrsize(dst) : -1);
 	if ((bits < 0) || (bits > ip_maxbits(dst)))
 		ereport(ERROR,
@@ -145,7 +145,7 @@ network_out(inet *src, bool is_cidr)
 	char	   *dst;
 	int			len;
 
-	dst = inet_net_ntop(ip_family(src), ip_addr(src), ip_bits(src),
+	dst = pg_inet_net_ntop(ip_family(src), ip_addr(src), ip_bits(src),
 						   tmp, sizeof(tmp));
 	if (dst == NULL)
 		ereport(ERROR,
@@ -1192,7 +1192,7 @@ network_host(PG_FUNCTION_ARGS)
 	char		tmp[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255/128")];
 
 	/* force display of max bits, regardless of masklen... */
-	if (inet_net_ntop(ip_family(ip), ip_addr(ip), ip_maxbits(ip),
+	if (pg_inet_net_ntop(ip_family(ip), ip_addr(ip), ip_maxbits(ip),
 						 tmp, sizeof(tmp)) == NULL)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
@@ -1217,7 +1217,7 @@ network_show(PG_FUNCTION_ARGS)
 	int			len;
 	char		tmp[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255/128")];
 
-	if (inet_net_ntop(ip_family(ip), ip_addr(ip), ip_maxbits(ip),
+	if (pg_inet_net_ntop(ip_family(ip), ip_addr(ip), ip_maxbits(ip),
 						 tmp, sizeof(tmp)) == NULL)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_BINARY_REPRESENTATION),
@@ -1240,7 +1240,7 @@ inet_abbrev(PG_FUNCTION_ARGS)
 	char	   *dst;
 	char		tmp[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255/128")];
 
-	dst = inet_net_ntop(ip_family(ip), ip_addr(ip),
+	dst = pg_inet_net_ntop(ip_family(ip), ip_addr(ip),
 						   ip_bits(ip), tmp, sizeof(tmp));
 
 	if (dst == NULL)
@@ -1258,7 +1258,7 @@ cidr_abbrev(PG_FUNCTION_ARGS)
 	char	   *dst;
 	char		tmp[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255/128")];
 
-	dst = inet_cidr_ntop(ip_family(ip), ip_addr(ip),
+	dst = pg_inet_cidr_ntop(ip_family(ip), ip_addr(ip),
 							ip_bits(ip), tmp, sizeof(tmp));
 
 	if (dst == NULL)

src/include/port.h

@@ -503,7 +503,7 @@ extern int	pg_codepage_to_encoding(UINT cp);
 #endif
 
 /* port/inet_net_ntop.c */
-extern char *inet_net_ntop(int af, const void *src, int bits,
+extern char *pg_inet_net_ntop(int af, const void *src, int bits,
 							  char *dst, size_t size);
 
 /* port/pg_strong_random.c */

src/include/utils/builtins.h

@@ -87,11 +87,11 @@ extern void text_to_cstring_buffer(const text *src, char *dst, size_t dst_len);
 extern int	xidComparator(const void *arg1, const void *arg2);
 
 /* inet_cidr_ntop.c */
-extern char *inet_cidr_ntop(int af, const void *src, int bits,
+extern char *pg_inet_cidr_ntop(int af, const void *src, int bits,
 							   char *dst, size_t size);
 
 /* inet_net_pton.c */
-extern int	inet_net_pton(int af, const char *src,
+extern int	pg_inet_net_pton(int af, const char *src,
 							 void *dst, size_t size);
 
 /* network.c */

src/interfaces/libpq/fe-connect.c

@@ -1539,7 +1539,7 @@ getHostaddr(PGconn *conn, char *host_addr, int host_addr_len)
 
 	if (addr->ss_family == AF_INET)
 	{
-		if (inet_net_ntop(AF_INET,
+		if (pg_inet_net_ntop(AF_INET,
 							 &((struct sockaddr_in *) addr)->sin_addr.s_addr,
 							 32,
 							 host_addr, host_addr_len) == NULL)
@@ -1548,7 +1548,7 @@ getHostaddr(PGconn *conn, char *host_addr, int host_addr_len)
 #ifdef HAVE_IPV6
 	else if (addr->ss_family == AF_INET6)
 	{
-		if (inet_net_ntop(AF_INET6,
+		if (pg_inet_net_ntop(AF_INET6,
 							 &((struct sockaddr_in6 *) addr)->sin6_addr.s6_addr,
 							 128,
 							 host_addr, host_addr_len) == NULL)

src/port/getaddrinfo.c

@@ -387,7 +387,8 @@ getnameinfo(const struct sockaddr *sa, int salen,
 	{
 		if (sa->sa_family == AF_INET)
 		{
-			if (inet_net_ntop(AF_INET, &((struct sockaddr_in *) sa)->sin_addr,
+			if (pg_inet_net_ntop(AF_INET,
+								 &((struct sockaddr_in *) sa)->sin_addr,
 								 sa->sa_family == AF_INET ? 32 : 128,
 								 node, nodelen) == NULL)
 				return EAI_MEMORY;

src/port/inet_net_ntop.c

@@ -36,7 +36,7 @@ static const char rcsid[] = "Id: inet_net_ntop.c,v 1.1.2.2 2004/03/09 09:17:27 m
 #else
 /*
  * In a frontend build, we can't include inet.h, but we still need to have
- * sensible definitions of these two constants.  Note that inet_net_ntop()
+ * sensible definitions of these two constants.  Note that pg_inet_net_ntop()
  * assumes that PGSQL_AF_INET is equal to AF_INET.
  */
 #define PGSQL_AF_INET	(AF_INET + 0)
@@ -61,20 +61,20 @@ static char *inet_net_ntop_ipv6(const u_char *src, int bits,
 
 /*
  * char *
- * inet_net_ntop(af, src, bits, dst, size)
+ * pg_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
+ *	as called for by pg_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)
+pg_inet_net_ntop(int af, const void *src, int bits, char *dst, size_t size)
 {
 	/*
 	 * We need to cover both the address family constants used by the PG inet