has: generate the curl/has.h header

changed macro name, moved and renamed script to become docs/libcurl/has.pl,
generate code that is checksrc compliant

include/curl/Makefile.am

@@ -5,7 +5,7 @@
 #                            | (__| |_| |  _ <| |___
 #                             \___|\___/|_| \_\_____|
 #
-# Copyright (C) 1998 - 2011, Daniel Stenberg, <daniel@haxx.se>, et al.
+# Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
 #
 # This software is licensed as described in the file COPYING, which
 # you should have received as part of this distribution. The terms
@@ -21,7 +21,7 @@
 ###########################################################################
 pkginclude_HEADERS = \
 	curl.h curlver.h easy.h mprintf.h stdcheaders.h multi.h \
-	typecheck-gcc.h curlbuild.h curlrules.h
+	typecheck-gcc.h curlbuild.h curlrules.h has.h
 
 pkgincludedir= $(includedir)/curl
 
@@ -40,14 +40,19 @@ pkgincludedir= $(includedir)/curl
 #
 # curlbuild.h.dist is not included in the source code distribution archive.
 
-EXTRA_DIST = curlbuild.h.in
+EXTRA_DIST = curlbuild.h.in has.pl
 
-DISTCLEANFILES = curlbuild.h
+DISTCLEANFILES = curlbuild.h has.h
+
+has.h: $(top_srcdir)/docs/libcurl/symbols-in-versions has.pl
+	@@PERL@ has.pl < $(top_srcdir)/docs/libcurl/symbols-in-versions > has.h
 
 checksrc:
-	@@PERL@ $(top_srcdir)/lib/checksrc.pl -Wcurlbuild.h -D$(top_srcdir)/include/curl $(pkginclude_HEADERS) $(EXTRA_DIST)
+	@@PERL@ $(top_srcdir)/lib/checksrc.pl -Wcurlbuild.h -D$(top_srcdir)/include/curl $(pkginclude_HEADERS) curlbuild.h.in
 
 if CURLDEBUG
 # for debug builds, we scan the sources on all regular make invokes
-all-local: checksrc
+all-local: has.h checksrc
+else
+all-local: has.h
 endif

include/curl/has.pl

@@ -0,0 +1,142 @@
+#!/usr/bin/perl
+#***************************************************************************
+#                                  _   _ ____  _
+#  Project                     ___| | | |  _ \| |
+#                             / __| | | | |_) | |
+#                            | (__| |_| |  _ <| |___
+#                             \___|\___/|_| \_\_____|
+#
+# Copyright (C) 2011-2015, Daniel Stenberg, <daniel@haxx.se>, et al.
+#
+# This software is licensed as described in the file COPYING, which
+# you should have received as part of this distribution. The terms
+# are also available at http://curl.haxx.se/docs/copyright.html.
+#
+# You may opt to use, copy, modify, merge, publish, distribute and/or sell
+# copies of the Software, and permit persons to whom the Software is
+# furnished to do so, under the terms of the COPYING file.
+#
+# This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+# KIND, either express or implied.
+#
+###########################################################################
+#
+# Experience has shown that the symbols-in-versions file is very useful to
+# applications that want to build with a wide range of libcurl versions.
+# It is however easy to get it wrong and the source gets a bit messy with all
+# the fixed numerical comparisons.
+#
+# The point of this script is to provide an easy-to-use macro for libcurl-
+# using applications to do preprocessor checks for specific libcurl defines,
+# and yet make the code clearly show what the macro is used for.
+#
+# Run this script and generate curl/has.h and then use that header in
+# a fashion similar to:
+#
+# #include <curl/has.h>
+#
+# #if CURL_HAS(CURLOPT_MUTE)
+#   has mute
+# #else
+#   no mute
+# #endif
+#
+#
+
+sub str2num {
+    my ($str)=@_;
+    if($str =~ /([0-9]*)\.([0-9]*)\.*([0-9]*)/) {
+        return sprintf("0x%06x", $1<<16 | $2 << 8 | $3);
+    }
+}
+
+print <<EOS
+#ifndef __CURL_HAS_H
+#define __CURL_HAS_H
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \\| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \\___|\\___/|_| \\_\\_____|
+ *
+ * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at http://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ***************************************************************************/
+/*
+ * This file is generated. Do not edit by hand. Edit
+ * docs/libcurl/symbols-in-versions and regenerate this with has.pl
+ */
+#include <curl/curlver.h>
+
+/*
+ * #include <curl/has.h>
+ *
+ * #if CURL_HAS(CURLOPT_MUTE)
+ *    use_mute();
+ * #else
+ *    without_mute();
+ * #endif
+ */
+#define CURL_HAS_IN(x,y) \\
+  (defined(CURLHAS_ ## x ) && (CURLHAS_ ## x <= y) && \\
+   (!defined(CURLHAS_ ## x ## _L) || ( CURLHAS_ ## x ## _L >= y)))
+
+#define CURL_HAS(x) CURL_HAS_IN(x, LIBCURL_VERSION_NUM)
+
+EOS
+    ;
+
+while(<STDIN>) {
+    if(/^(CURL[^ ]*)[ \t]*(.*)/) {
+        my ($sym, $vers)=($1, $2);
+
+        my $intr;
+        my $rm;
+        my $dep;
+
+        # is there removed info?
+        if($vers =~ /([\d.]+)[ \t-]+([\d.-]+)[ \t]+([\d.]+)/) {
+            ($intr, $dep, $rm)=($1, $2, $3);
+        }
+        # is it a dep-only line?
+        elsif($vers =~ /([\d.]+)[ \t-]+([\d.]+)/) {
+            ($intr, $dep)=($1, $2);
+        }
+        else {
+            $intr = $vers;
+        }
+
+        my $inum = str2num($intr);
+
+        print <<EOS
+#define CURLHAS_${sym} $inum /* $intr */
+EOS
+;
+        my $irm = str2num($rm);
+        if($rm) {
+        print <<EOS
+#define CURLHAS_${sym}_L $irm /* Last $rm */
+EOS
+;
+        }
+
+    }
+}
+
+print <<EOS
+#endif /* __CURL_HAS_H */
+
+EOS
+    ;