libreplace: replace inet_ntoa() when it is missing

...not only replace it when it is broken.

This moves the defintion of rep_inet_ntoa from replace.c
to inet_ntoa.c and adds configure checks for existence
of inet_ntoa(). Checks are moved to an include file of its own.

NOTE: The original rep_inet_ntoa in replace.c was wrapped
into a "#ifndef WITH_PTHREADS" but the prototype in replace.h
and the define in system/network.h were not. I removed that
ifndef since the inet_ntoa() function is usually not thread safe
anyways, since it returns a pointer to a static buffer.

So whoever calls inet_ntoa() should be aware that it is not
thread safe anyways.

Michael
(cherry picked from commit 974c0c45ad)
(This used to be commit edcf2712bc)

source3/lib/replace/inet_ntoa.c

@@ -0,0 +1,39 @@
+/*
+ * Unix SMB/CIFS implementation.
+ * replacement routines for broken systems
+ * Copyright (C) Andrew Tridgell 2003
+ * Copyright (C) Michael Adam 2008
+ *
+ *  ** NOTE! The following LGPL license applies to the replace
+ *  ** library. This does NOT imply that all of Samba is released
+ *  ** under the LGPL
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "replace.h"
+#include "system/network.h"
+
+/**
+ * NOTE: this is not thread safe, but it can't be, either
+ * since it returns a pointer to static memory.
+ */
+char *rep_inet_ntoa(struct in_addr ip)
+{
+	uint8_t *p = (uint8_t *)&ip.s_addr;
+	static char buf[18];
+	slprintf(buf, 17, "%d.%d.%d.%d", 
+		 (int)p[0], (int)p[1], (int)p[2], (int)p[3]);
+	return buf;
+}

source3/lib/replace/inet_ntoa.m4

@@ -0,0 +1,19 @@
+AC_CHECK_FUNCS(inet_ntoa,[],[LIBREPLACEOBJ="${LIBREPLACEOBJ} inet_ntoa.o"])
+
+AC_CACHE_CHECK([for broken inet_ntoa],libreplace_cv_REPLACE_INET_NTOA,[
+AC_TRY_RUN([
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <netinet/in.h>
+#ifdef HAVE_ARPA_INET_H
+#include <arpa/inet.h>
+#endif
+main() { struct in_addr ip; ip.s_addr = 0x12345678;
+if (strcmp(inet_ntoa(ip),"18.52.86.120") &&
+    strcmp(inet_ntoa(ip),"120.86.52.18")) { exit(0); } 
+exit(1);}],
+           libreplace_cv_REPLACE_INET_NTOA=yes,libreplace_cv_REPLACE_INET_NTOA=no,libreplace_cv_REPLACE_INET_NTOA=cross)])
+if test x"$libreplace_cv_REPLACE_INET_NTOA" = x"yes"; then
+    AC_DEFINE(REPLACE_INET_NTOA,1,[Whether inet_ntoa should be replaced])
+fi

source3/lib/replace/libreplace.m4

@@ -120,24 +120,6 @@ if test x"$libreplace_cv_USABLE_NET_IF_H" = x"yes";then
 	AC_DEFINE(HAVE_NET_IF_H, 1, usability of net/if.h)
 fi
 
-AC_CACHE_CHECK([for broken inet_ntoa],libreplace_cv_REPLACE_INET_NTOA,[
-AC_TRY_RUN([
-#include <stdio.h>
-#include <unistd.h>
-#include <sys/types.h>
-#include <netinet/in.h>
-#ifdef HAVE_ARPA_INET_H
-#include <arpa/inet.h>
-#endif
-main() { struct in_addr ip; ip.s_addr = 0x12345678;
-if (strcmp(inet_ntoa(ip),"18.52.86.120") &&
-    strcmp(inet_ntoa(ip),"120.86.52.18")) { exit(0); } 
-exit(1);}],
-           libreplace_cv_REPLACE_INET_NTOA=yes,libreplace_cv_REPLACE_INET_NTOA=no,libreplace_cv_REPLACE_INET_NTOA=cross)])
-if test x"$libreplace_cv_REPLACE_INET_NTOA" = x"yes"; then
-    AC_DEFINE(REPLACE_INET_NTOA,1,[Whether inet_ntoa should be replaced])
-fi
-
 AC_HAVE_TYPE([socklen_t],[#include <sys/socket.h>])
 AC_HAVE_TYPE([sa_family_t],[#include <sys/socket.h>])
 AC_HAVE_TYPE([struct addrinfo], [#include <netdb.h>])
@@ -348,6 +330,7 @@ m4_include(socket.m4)
 m4_include(inet_ntop.m4)
 m4_include(inet_pton.m4)
 m4_include(inet_aton.m4)
+m4_include(inet_ntoa.m4)
 m4_include(getaddrinfo.m4)
 m4_include(repdir.m4)
 m4_include(getifaddrs.m4)

source3/lib/replace/replace.c

@@ -295,20 +295,6 @@ char *rep_strdup(const char *s)
 }
 #endif /* HAVE_STRDUP */
 
-#ifndef WITH_PTHREADS
-/* REWRITE: not thread safe */
-#ifdef REPLACE_INET_NTOA
-char *rep_inet_ntoa(struct in_addr ip)
-{
-	uint8_t *p = (uint8_t *)&ip.s_addr;
-	static char buf[18];
-	slprintf(buf, 17, "%d.%d.%d.%d", 
-		 (int)p[0], (int)p[1], (int)p[2], (int)p[3]);
-	return buf;
-}
-#endif /* REPLACE_INET_NTOA */
-#endif
-
 #ifndef HAVE_SETLINEBUF
 void rep_setlinebuf(FILE *stream)
 {

source3/lib/replace/replace.h

@@ -325,7 +325,7 @@ ssize_t rep_pread(int __fd, void *__buf, size_t __nbytes, off_t __offset);
 ssize_t rep_pwrite(int __fd, const void *__buf, size_t __nbytes, off_t __offset);
 #endif
 
-#ifdef REPLACE_INET_NTOA
+#if !defined(HAVE_INET_NTOA) || defined(REPLACE_INET_NTOA)
 #define inet_ntoa rep_inet_ntoa
 /* prototype is in "system/network.h" */
 #endif

source3/lib/replace/system/network.h

@@ -88,7 +88,7 @@
 typedef int socklen_t;
 #endif
 
-#ifdef REPLACE_INET_NTOA
+#if !defined (HAVE_INET_NTOA) || defined(REPLACE_INET_NTOA)
 /* define is in "replace.h" */
 char *rep_inet_ntoa(struct in_addr ip);
 #endif