Define OPENSSL_API_COMPAT

This avoids deprecation warnings from newer OpenSSL versions (3.0.0 in
particular).

This has been originally applied as 4d3db13 for v14 and newer versions,
but not on the older branches out of caution, and this commit closes the
gap to remove all these deprecation warnings in all the branches still
supported.

OPENSSL_API_COMPAT's value is set based on the oldest version of OpenSSL
supported on a branch: 1.0.1 for Postgres 13 and 0.9.8 for Postgres 11
and 12.

Reviewed-by: Daniel Gustafsson
Discussion: https://postgr.es/m/FEF81714-D479-4512-839B-C769D2605F8A@yesql.se
Discussion: https://postgr.es/m/ZJJmOH+hIOSoesux@paquier.xyz
Backpatch-through: 11

configure

@@ -12477,7 +12477,11 @@ fi
 fi
 
 if test "$with_openssl" = yes ; then
-    if test "$PORTNAME" != "win32"; then
+    # Minimum required OpenSSL version is 1.0.1
+
+$as_echo "#define OPENSSL_API_COMPAT 0x10001000L" >>confdefs.h
+
+  if test "$PORTNAME" != "win32"; then
      { $as_echo "$as_me:${as_lineno-$LINENO}: checking for CRYPTO_new_ex_data in -lcrypto" >&5
 $as_echo_n "checking for CRYPTO_new_ex_data in -lcrypto... " >&6; }
 if ${ac_cv_lib_crypto_CRYPTO_new_ex_data+:} false; then :

configure.in

@@ -1258,6 +1258,9 @@ fi
 
 if test "$with_openssl" = yes ; then
   dnl Order matters!
+  # Minimum required OpenSSL version is 1.0.1
+  AC_DEFINE(OPENSSL_API_COMPAT, [0x10001000L],
+            [Define to the OpenSSL API version in use. This avoids deprecation warnings from newer OpenSSL versions.])
   if test "$PORTNAME" != "win32"; then
      AC_CHECK_LIB(crypto, CRYPTO_new_ex_data, [], [AC_MSG_ERROR([library 'crypto' is required for OpenSSL])])
      AC_CHECK_LIB(ssl,    SSL_new, [], [AC_MSG_ERROR([library 'ssl' is required for OpenSSL])])

src/include/pg_config.h.in

@@ -758,6 +758,10 @@
 /* Define bytes to use libc memset(). */
 #undef MEMSET_LOOP_LIMIT
 
+/* Define to the OpenSSL API version in use. This avoids deprecation warnings
+   from newer OpenSSL versions. */
+#undef OPENSSL_API_COMPAT
+
 /* Define to the address where bug reports for this package should be sent. */
 #undef PACKAGE_BUGREPORT
 

src/tools/msvc/Solution.pm

@@ -152,6 +152,8 @@ sub GenerateFiles
 	my $package_bugreport;
 	my $package_url;
 	my ($majorver, $minorver);
+	my $ac_define_openssl_api_compat_found = 0;
+	my $openssl_api_compat;
 
 	# Parse configure.in to get version numbers
 	open(my $c, '<', "configure.in")
@@ -176,10 +178,15 @@ sub GenerateFiles
 			$majorver = sprintf("%d", $1);
 			$minorver = sprintf("%d", $2 ? $2 : 0);
 		}
+		elsif (/\bAC_DEFINE\(OPENSSL_API_COMPAT, \[([0-9xL]+)\]/)
+		{
+			$ac_define_openssl_api_compat_found = 1;
+			$openssl_api_compat = $1;
+		}
 	}
 	close($c);
 	confess "Unable to parse configure.in for all variables!"
-	  unless $ac_init_found;
+	  unless $ac_init_found && $ac_define_openssl_api_compat_found;
 
 	if (IsNewer("src/include/pg_config_os.h", "src/include/port/win32.h"))
 	{
@@ -436,6 +443,7 @@ sub GenerateFiles
 		LOCALE_T_IN_XLOCALE                      => undef,
 		MAXIMUM_ALIGNOF                          => 8,
 		MEMSET_LOOP_LIMIT                        => 1024,
+		OPENSSL_API_COMPAT                       => $openssl_api_compat,
 		PACKAGE_BUGREPORT                        => qq{"$package_bugreport"},
 		PACKAGE_NAME                             => qq{"$package_name"},
 		PACKAGE_STRING      => qq{"$package_name $package_version"},