From: Masahiro TANAKA <masa16.tanaka@gmail.com>
Date: Tue, 5 Mar 2013 18:46:58 +0900
Subject: extconf.rb: * need to check extra-libs before auto-build. * need to
 define $found_lib. * define methods to make program structure clear. * merge
 extconf-auto.rb.

---
 ext/extconf.rb | 280 +++++++++++++++++++++++++++++++++++----------------------
 1 file changed, 171 insertions(+), 109 deletions(-)

diff --git a/ext/extconf.rb b/ext/extconf.rb
index 48d1c1b..02a1672 100644
--- a/ext/extconf.rb
+++ b/ext/extconf.rb
@@ -1,30 +1,67 @@
-# extconf.rb : Configure script for Ruby/PGPLOT
-#
-#   Copyright (c) 2000,2001 Masahiro TANAKA <masa@ir.isas.ac.jp>
-#
-#   This program is free software.
-#   You can distribute/modify this program
-#   under the same terms as Ruby itself.
-#   NO WARRANTY.
-#
-# usage: ruby extconf.rb [configure options]
-
-# Narray is now Gem based, so require rubygems
-# so that we can use Gem class to find narray.
 require "mkmf"
 
-#$DEBUG = true
+def main
+  extconf_start
+  check_narray
 
-# configure options:
-#  --with-pgplot-dir=path
-#  --with-pgplot-include=path
-#  --with-pgplot-lib=path
-dir_config("pgplot")
+  $objs = %w(rb_pgplot.o kwarg.o)
+  $enable_autobuild = enable_config('autobuild', false)
+  $found_lib = []
+
+  # Check PGPLOT Header
+  if have_header("cpgplot.h")
+    if have_library("cpgplot","cpgbeg")
+      create_makefile("pgplot")
+      exit
+    end
+
+    # Check for extra libs then re-check for PGPLOT library
+    puts "First check for PGPLOT library failed."
+    check_extra_libs
+    $libs = append_library($libs, "pgplot")
+
+    if have_library("cpgplot","cpgbeg")
+      create_makefile("pgplot")
+      exit
+    end
+  elsif $enable_autobuild
+    check_extra_libs
+  end
+
+  if $enable_autobuild
+    autobuild_pgplot
+  else
+    puts "
+The PGPLOT library was not found.  To auto-build PGPLOT library
+as part of installing Ruby/PGPLOT, pass the --enable-autobuild option.
+
+Examples:
+     Gem install:  gem install pgplot -- --enable-autobuild
+  Manual install:  ruby extconf.rb --enable-autobuild
+"
+  end
+end
+
+
+def extconf_start
+  # configure options:
+  #  --with-pgplot-dir=path
+  #  --with-pgplot-include=path
+  #  --with-pgplot-lib=path
+  dir_config("pgplot")
+
+  # configure options:
+  #  --with-x11-dir=path
+  #  --with-x11-include=path
+  #  --with-x11-lib=path
+  dir_config("x11")
+
+  # Otherwise you can also specify:
+  #  --with-opt-dir=path
+  #  --with-opt-include=path
+  #  --with-opt-lib=path
+end
 
-# Otherwise you can also specify:
-#  --with-opt-dir=path
-#  --with-opt-include=path
-#  --with-opt-lib=path
 
 def find_dir_w_file(d,h)
   g = Dir.glob(RbConfig.expand(d+"/"+h))
@@ -42,107 +79,132 @@ def find_dir_in_gemspec
   nil
 end
 
-# Check NArray
-gems_dir="$(rubylibprefix)/gems/$(ruby_version)/gems/"
-narray_d="narray-0.[56].*"
-narray_h="narray.h"
-if narray_h_dir =
-    find_dir_in_gemspec ||
-    find_dir_w_file("../"+narray_d,narray_h) ||
-    find_dir_w_file(gems_dir+narray_d,narray_h) ||
-    find_dir_w_file(CONFIG['vendorarchdir'],narray_h) ||
-    find_dir_w_file(CONFIG['sitearchdir'],narray_h) ||
-    find_dir_w_file(CONFIG['archdir'],narray_h) 
-  $CPPFLAGS = " -I#{narray_h_dir} " + $CPPFLAGS
-end
-exit unless have_header("narray.h")
 
-if RUBY_PLATFORM =~ /cygwin|mingw/
-  $LDFLAGS = " -L#{CONFIG['sitearchdir']} "+$LDFLAGS
-  exit unless have_library("narray","na_make_object")
-end
+def check_narray
+  gems_dir="$(rubylibprefix)/gems/$(ruby_version)/gems/"
+  narray_d="narray-0.[56].*"
+  narray_h="narray.h"
+  if narray_h_dir =
+      find_dir_in_gemspec ||
+      find_dir_w_file("../"+narray_d,narray_h) ||
+      find_dir_w_file(gems_dir+narray_d,narray_h) ||
+      find_dir_w_file(CONFIG['vendorarchdir'],narray_h) ||
+      find_dir_w_file(CONFIG['sitearchdir'],narray_h) ||
+      find_dir_w_file(CONFIG['archdir'],narray_h)
+    $CPPFLAGS = " -I#{narray_h_dir} " + $CPPFLAGS
+  end
+  exit unless have_header("narray.h")
 
-$have_pgplot = false
+  if RUBY_PLATFORM =~ /cygwin|mingw/
+    $LDFLAGS = " -L#{CONFIG['sitearchdir']} "+$LDFLAGS
+    exit unless have_library("narray","na_make_object")
+  end
+end
 
-# Check PGPLOT Header
-if have_header("cpgplot.h")
 
-  # Check PGPLOT Library without extra libs
-  if find_library("cpgplot","cpgbeg", "/usr/lib",
-		  "/usr/local/lib", "/usr/local/pgplot" )
-    $have_pgplot = true
+def check_extra_libs
+  # Check FORTRAN Libraries
+  #
+  # SUN WorkShop FORTRAN 77 compiler ver5.0
+  # configure options: --with-sunws
+  if with_config("sunws")
+    $libs = "-lM77 -lsunmath "+$libs
+    exit unless find_library("F77", "f77_init", "/opt/SUNWspro/lib")
+    $defs.push "-DSPARC_FORTRAN"
+  #
+  # GNU FORTRAN v4
+  elsif have_library("gfortran")
+    $CFLAGS = "-Wall "+$CFLAGS
+    $defs.push "-DGNU_FORTRAN"
+  #
+  # GNU FORTRAN v3
+  elsif have_library("g77")
+    $CFLAGS = "-Wall "+$CFLAGS
+    $defs.push "-DGNU_FORTRAN"
   else
-    # Check for extra libs then re-check for PGPLOT library
-    puts "First check for PGPLOT library failed,"
-    puts "checking for auxiliary libraries and retrying."
-
-    # Check FORTRAN Libraries
-    #
-    # SUN WorkShop FORTRAN 77 compiler ver5.0
-    # configure options: --with-sunws
-    if with_config("sunws")
-      $libs = "-lM77 -lsunmath "+$libs
-      exit unless find_library("F77", "f77_init", "/opt/SUNWspro/lib")
-      $defs.push "-DSPARC_FORTRAN"
-    #
-    # GNU FORTRAN v4
-    elsif have_library("gfortran")
-      $CFLAGS = "-Wall "+$CFLAGS
-      $defs.push "-DGNU_FORTRAN"
-    #
-    # GNU FORTRAN v3
-    elsif have_library("g77")
-      $CFLAGS = "-Wall "+$CFLAGS
-      $defs.push "-DGNU_FORTRAN"
-    else
-      puts "failed"
-      exit
-    end
+    puts "failed"
+    exit
+  end
 
-    # Check GrWin Library (for cygwin (and mingw32?))
-    #  configure options: --with-grwin
-    if with_config("grwin")
-      #$LDFLAGS = "-Wl,--subsystem,console "+$LDFLAGS
-      if RUBY_PLATFORM =~ /cygwin|mingw/
-        $libs += " -mwindows"
-      end
-      exit unless have_library("GrWin", "GWinit")
+  # Check GrWin Library (for cygwin (and mingw32?))
+  #  configure options: --with-grwin
+  if with_config("grwin")
+    #$LDFLAGS = "-Wl,--subsystem,console "+$LDFLAGS
+    if RUBY_PLATFORM =~ /cygwin|mingw/
+      $libs += " -mwindows"
     end
+    exit unless have_library("GrWin", "GWinit")
+  end
+
+  # Check X11 Library
+  if have_library("X11", "XOpenDisplay")
+    $found_lib << 'X11'
+  end
 
-    $found_lib = []
+  # Check PNG Library
+  libs_save = $libs
+  $libs = append_library($libs, "z")
+  if have_library("png","png_create_write_struct")
+    $found_lib << 'png'
+  else
+    $libs = libs_save
+  end
+end
 
-    # configure options:
-    #  --with-x11-dir=path
-    #  --with-x11-include=path
-    #  --with-x11-lib=path
-    dir_config("x11")
 
-    # Check X11 Library
-    if have_library("X11", "XOpenDisplay")
-      $found_lib << 'X11'
-    end
+def autobuild_pgplot
+  # Exit unless a fortran compiler was found
+  exit unless %w[gfortran g77].any?{|cmd| system("which #{cmd}")}
+  puts "enabling auto-build PGPLOT Library..."
 
-    # Check PNG Library
-    libs_save = $libs
-    $libs = append_library($libs, "z")
-    if have_library("png","png_create_write_struct")
-      $found_lib << 'png'
-    else
-      $libs = libs_save
-    end
+  $subdir = 'build_lib'
+  $CFLAGS = "-I#{$subdir}/build "+$CFLAGS
+  $LDFLAGS = "-L#{$subdir}/build "+$LDFLAGS
+  $libs = append_library($libs, "cpgplot")
+  $defs.push '-DPGPLOT_DIR=\\"$(PGPLOT_DIR)\\"'
 
-    $libs = append_library($libs, "pgplot")
+  # Generate Makefile
+  create_makefile("pgplot")
 
-    if find_library("cpgplot","cpgbeg", "/usr/lib",
-        "/usr/local/lib", "/usr/local/pgplot" )
-      $have_pgplot = true
+  # Append PGPLOT install task to Makefile
+  exit unless $makefile_created
+  puts "appending extra install tasks to Makefile"
+  File.open("Makefile","a") do |w|
+    w.print "
+PGPLOT_DIR = $(RUBYARCHDIR)/pgplot
+PGPLOT_BUILD = #{$subdir}/build
+
+$(PGPLOT_BUILD)/libcpgplot.a:
+	(cd #{$subdir}; make build/libcpgplot.a)
+$(PGPLOT_BUILD)/cpgplot.h: $(PGPLOT_BUILD)/libcpgplot.a
+rb_pgplot.o: $(PGPLOT_BUILD)/cpgplot.h
+$(DLLIB): $(PGPLOT_BUILD)/libcpgplot.a
+
+install: install-pgplot
+install-pgplot:
+	$(MAKEDIRS) $(PGPLOT_DIR)
+	$(INSTALL_DATA) $(PGPLOT_BUILD)/grfont.dat $(PGPLOT_DIR)
+	$(INSTALL_DATA) $(PGPLOT_BUILD)/rgb.txt $(PGPLOT_DIR)
+"
+    if $found_lib.include? "X11"
+      w.print \
+"	$(INSTALL_PROG) $(PGPLOT_BUILD)/pgxwin_server $(PGPLOT_DIR)
+
+$(PGPLOT_BUILD)/pgxwin_server: $(PGPLOT_BUILD)/cpgplot.h
+	(cd #{$subdir}; make build/pgxwin_server)
+$(DLLIB): $(PGPLOT_BUILD)/pgxwin_server
+"
     end
   end
-end
 
-$objs = %w(rb_pgplot.o kwarg.o)
+  puts "creating #{$subdir}/drivers.conf"
+  File.open("#{$subdir}/drivers.conf","w") do |w|
+    w.puts "GIDRIV PPDRIV PSDRIV"
+    w.puts "PNDRIV" if $found_lib.include? "png"
+    w.puts "WDDRIV XWDRIV" if $found_lib.include? "X11"
+  end
 
-if $have_pgplot
-  # Generate Makefile
-  create_makefile("pgplot")
+  puts "Ready to download and auto-build PGPLOT !!"
 end
+
+main