[PATCHv7.1 1/4] gitweb: Prepare for splitting gitweb

From: Jakub Narebski <jnareb@gmail.com>
Date: Nov 1, 2010, 10:24 UTC
Message-ID: <1288607092-31458-2-git-send-email-jnareb@gmail.com>
In-Reply-To: <201010311021.55917.jnareb@gmail.com>

Prepare gitweb for having been split into modules that are to be installed alongside gitweb in 'lib/' subdirectory, by adding

  use lib __DIR__.'/lib';

to gitweb.perl (to main gitweb script), and preparing for putting modules (relative path) in $(GITWEB_MODULES) in gitweb/Makefile.

This preparatory work allows to add new module to gitweb by simply adding

  GITWEB_MODULES += <module>

to gitweb/Makefile (assuming that the module is in 'gitweb/lib/' directory).

Using __DIR__ from Dir::Self module (not in core, that's why currently gitweb includes excerpt of code from Dir::Self defining __DIR__) was chosen over using FindBin-based solution (in core since perl 5.00307, while gitweb itself requires at least perl 5.8.0) because FindBin uses BEGIN block, which is a problem under mod_perl and other persistent Perl environments (thought there are workarounds).

At Pavan Kumar Sankara suggestion gitweb/Makefile uses

  install [OPTION]... SOURCE... DIRECTORY

format (2nd format) with single SOURCE rather than

  install [OPTION]... SOURCE DEST

format (1st format) because of security reasons (race conditions). Modern GNU install has `-T' / `--no-target-directory' option, but we cannot rely that the $(INSTALL) we are using supports this option.

The install-modules target in gitweb/Makefile uses shell 'for' loop, instead of make's $(foreach) function, to avoid possible problem with generating a command line that exceeded the maximum argument list length.

Signed-off-by: Jakub Narebski <jnareb@gmail.com>
---
This patch would conflict with the patch 958a846 (gitweb/Makefile: Add
'test' and 'test-installed' targets, 2010-09-26), which is in 'pu'.
Resolving those conflicts is easy, though non-trivial.

Please tell me if I should send this series rebased on top of 'jn/gitweb-test' (which includes 958a846) instead.

This patch introduces infrastructure which would be required later for splitting gitweb.

 gitweb/Makefile    |   17 ++++++++++++++---
 gitweb/gitweb.perl |    8 ++++++++
 2 files changed, 22 insertions(+), 3 deletions(-)

diff --git a/gitweb/Makefile b/gitweb/Makefile
index 2fb7c2d..6fa7625 100644
--- a/gitweb/Makefile
+++ b/gitweb/Makefile
@@ -55,6 +55,7 @@ PERL_PATH  ?= /usr/bin/perl
 bindir_SQ = $(subst ','\'',$(bindir))#'
 gitwebdir_SQ = $(subst ','\'',$(gitwebdir))#'
 gitwebstaticdir_SQ = $(subst ','\'',$(gitwebdir)/static)#'
+gitweblibdir_SQ = $(subst ','\'',$(gitwebdir)/lib)#'
 SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))#'
 PERL_PATH_SQ  = $(subst ','\'',$(PERL_PATH))#'
 DESTDIR_SQ    = $(subst ','\'',$(DESTDIR))#'
@@ -145,16 +146,26 @@ gitweb.cgi: gitweb.perl GITWEB-BUILD-OPTIONS
 
 ### Installation rules
 
-install: all
+install: all install-modules
 	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(gitwebdir_SQ)'
 	$(INSTALL) -m 755 $(GITWEB_PROGRAMS) '$(DESTDIR_SQ)$(gitwebdir_SQ)'
 	$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(gitwebstaticdir_SQ)'
 	$(INSTALL) -m 644 $(GITWEB_FILES) '$(DESTDIR_SQ)$(gitwebstaticdir_SQ)'
 
+install-modules:
+	install_dirs="$(sort $(dir $(GITWEB_MODULES)))" && \
+	for dir in $$install_dirs; do \
+		test -d '$(DESTDIR_SQ)$(gitweblibdir_SQ)/$$dir' || \
+		$(INSTALL) -d -m 755 '$(DESTDIR_SQ)$(gitweblibdir_SQ)/$$dir'; \
+	done
+	gitweb_modules="$(GITWEB_MODULES)" && \
+	for mod in $$gitweb_modules; do \
+		$(INSTALL) -m 644 lib/$$mod '$(DESTDIR_SQ)$(gitweblibdir_SQ)/$$(dirname $$mod)'; \
+	done
+
 ### Cleaning rules
 
 clean:
 	$(RM) gitweb.cgi static/gitweb.min.js static/gitweb.min.css GITWEB-BUILD-OPTIONS
 
-.PHONY: all clean install .FORCE-GIT-VERSION-FILE FORCE
-
+.PHONY: all clean install install-modules .FORCE-GIT-VERSION-FILE FORCE
diff --git a/gitweb/gitweb.perl b/gitweb/gitweb.perl
index d521b4c..e4c08ba 100755
--- a/gitweb/gitweb.perl
+++ b/gitweb/gitweb.perl
@@ -9,6 +9,14 @@
 
 use strict;
 use warnings;
+
+use File::Spec;
+# __DIR__ is taken from Dir::Self __DIR__ fragment
+sub __DIR__ () {
+	File::Spec->rel2abs(join '', (File::Spec->splitpath(__FILE__))[0, 1]);
+}
+use lib __DIR__ . '/lib';
+
 use CGI qw(:standard :escapeHTML -nosticky);
 use CGI::Util qw(unescape);
 use CGI::Carp qw(fatalsToBrowser set_message);

-- 
1.7.3