Arjen Lentz
We filed a wishlist bug for this, https://bugs.launchpad.net/maria/+bug/470580 which also includes a patch by Antony Curtis. It creates a mysql- glob.h during the build process, which we could put into a mariadb- plugin-dev package.
Then, some mariadb-xxxx packages can be build in the main mariadb build, and some can be separate. It also allows developers to work on plugins sanely. It cleans up the entire dev environment for this - it's not 100% pretty as it's a nasty big include, but it's a good step given the current mess.
I took a look at this (sorry for slight delay, have been swamped with lots of small tasks the last couple of days). I very much agree with the idea of having a plugin-dev package that is sufficient for building plugins. It seems it should be doable with not too much work. I know we already did some fixes in the MariaDB tree to make this possible. Basically some configure/CFLAGS options could affect the binary interface (think it was DEBUG / SAFEMALLOC flags). These were moved into config.h so that it is not necessary to guess the right values of these options to build a plugin that will load without crashing. We can do more of these kinds of fixes as needed. I do not understand the approach taken in the patch though. Seems to me to be the wrong approach? Though I could be misunderstanding, the patch doesn't contain much in the way of explanation / comments yet. So I was expecting to see somthing that collected a set of include files needed to build (storage engine) plugins, and putting them somewhere plugins could reference them. Instead, the patch seems to run the C pre-processor on mysql_priv.h, I assume to get a _single_ .h file with everything? And the result is passed through some Perl filter and munged in various interesting ways. So I guess my first question is why to do it this roundabout way at all? Why not just collect the necessary .h files? Seems much cleaner, simpler, easier to maintain, etc. If there are some issues with this, maybe we could instead fix these issues in the source? Thanks, - Kristian.
=== modified file 'sql/Makefile.am' --- old/sql/Makefile.am 2009-09-15 10:46:35 +0000 +++ new/sql/Makefile.am 2009-11-02 09:19:32 +0000 @@ -20,6 +20,7 @@ MYSQLBASEdir= $(prefix) MYSQLLIBdir= $(pkglibdir) pkgplugindir = $(pkglibdir)/plugin +globincldir = $(pkgincludedir)/mysql/$(VERSION) INCLUDES = @ZLIB_INCLUDES@ \ -I$(top_builddir)/include -I$(top_srcdir)/include \ -I$(top_srcdir)/regex -I$(srcdir) $(openssl_includes) \ @@ -29,6 +30,7 @@ libexec_PROGRAMS = mysqld EXTRA_PROGRAMS = gen_lex_hash bin_PROGRAMS = mysql_tzinfo_to_sql +globincl_HEADERS = mysql-glob.h
noinst_LTLIBRARIES= libndb.la \ udf_example.la @@ -179,6 +181,12 @@ ./gen_lex_hash$(EXEEXT) > $@-t $(MV) $@-t $@
+mysql-glob.h: mysql_priv.h + $(CXXCPP) -x c++-header $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) \ + $(AM_CPPFLAGS) $(CPPFLAGS) $(AM_CXXFLAGS) $(CXXFLAGS) \ + -CC -dDI $^ | $(PERL) $(srcdir)/make-mysql-glob.pl > $@-t + $(MV) $@-t $@ + # For testing of udf_example.so udf_example_la_SOURCES= udf_example.c udf_example_la_LDFLAGS= -module -rpath $(pkglibdir)
=== added file 'sql/make-mysql-glob.pl' --- old/sql/make-mysql-glob.pl 1970-01-01 00:00:00 +0000 +++ new/sql/make-mysql-glob.pl 2009-11-02 09:39:43 +0000 @@ -0,0 +1,179 @@ +#!/usr/bin/perl + +use strict; + +my $current_file; +my $current_line; +my $current_path; + +my @command_line= (); + +my $until_file; +my $until_line; + +my $last_include; + +my $echo= \&echo_on; +my $echo_line; + +my $first_define; +my $define_suffix = sub { }; + +sub canon($) +{ + my ($path)= @_; + my $tmp= $path; + $tmp =~ s@/[^/]+/\.\./@/@; + return canon($tmp) if $tmp ne $path; + return $path; +} + +$first_define = sub { + my ($line) = @_; + if ($line =~ m/^#define\s+([^\s]+)/) + { + my ($e,$d)= ($echo, $1); + $first_define = sub { return 0; }; + &$e("#ifndef MYSQL_GLOB_H\n#define MYSQL_GLOB_H\n#ifdef $d\n#error cannot mix headers\n#endif\n$line\n"); + foreach (@command_line) + { + &$e($_); + } + + $define_suffix= sub + { + &$e("#endif /* MYSQL_GLOB_H / $d */\n"); + }; + + return 1; + } + return 0; +}; + +sub echo_on($) +{ + my ($line) = @_; + + return if &$first_define($line); + return if $line =~ m/^#define\s+SHOW_FUNC\s+/; + + print $echo_line if defined $echo_line; + print $line; + undef $echo_line; +} + +sub echo_off($) +{ + my ($line)= @_; + if (($current_file eq $until_file) && ($current_line == $until_line)) + { + $echo= \&echo_on; + undef $until_file; + undef $until_line; + undef $echo_line; + echo_on($line) if !($line =~ m/^# /); + } +} + +sub echo_cmdline($) +{ + my ($line)= @_; + push @command_line, $line if + ($current_file ne $until_file) || ($current_line != $until_line); + echo_off($line); +} + +sub test_builtin($$) +{ + ($until_line, $until_file)= @_ if !defined($until_file); + $echo= \&echo_off; + return 0; +} + +sub test_cmdline($$) +{ + ($until_line, $until_file)= @_ if !defined($until_file); + $echo= \&echo_cmdline; + return 0; +} + +sub test_incpath($$) +{ + if ($current_line == 1) + { + ($until_line, $until_file)= @_ if !defined($until_file); + if ($current_line == 1) + { + undef $echo_line; + &$echo($last_include); + $echo= \&echo_off; + } + } + return 0; +} + +while (<>) +{ + my ($last_line, $last_file)= ($current_line, $current_file); + my $test= sub { return 1; }; + + if (m/^# (\d+) "(.*)"/) + { + ($current_line, $current_file)= (int $1,$2); + + if ($current_file =~ m/\/$/) + { + $current_path= $`; + ($current_line, $current_file)= ($last_line,$last_file); + next; + } + + $echo_line= $_; + + $test= sub + { + my $saved_echo= $echo; + $echo= sub + { + my ($line)= @_; + $echo= $saved_echo; + echo_off($line); + }; + return 1; + }; + + $test= sub { return test_builtin($last_line, $last_file); } if + $current_file eq '<built-in>'; + $test= sub { return test_cmdline($last_line, $last_file); } if + $current_file eq '<command line>'; + $test= sub { return test_incpath($last_line, $last_file); } if + $current_file =~ m/^\//; + + if (!($current_file =~ m/^\//)) + { + my $new_path= canon($current_path.$current_file); + $echo_line =~ s/"$current_file"/"$new_path"/; + } + $echo_line=~ s/^# /#line /; + + } + + if (m/^#include /) + { + $test= sub { + my $saved_echo= $echo; + $echo= sub { + ($last_include)= @_; + $echo= $saved_echo; + }; + return 1; + }; + } + + &$echo($_) if &$test(); + $current_line++; +} + +&$define_suffix(); + +exit 0;