Add a new Makefile flag, RUNTIME_PREFIX_PERL, which, when enabled,
configures Perl scripts to locate the Git installation's Perl support
libraries by resolving against the script's path, rather than
hard-coding that path at build-time.
RUNTIME_PREFIX_PERL requires that system paths are expressed relative to
a common installation directory, and uses that relationship to locate
support files based on the known starting point of the script being
executed, much like RUNTIME_PREFIX does for the Git binary.
This change enables Git's Perl scripts to work when their Git installation
is relocated or moved to another system.
Signed-off-by: Dan Jacques <dnj@xxxxxxxxxx>
Thanks-to: Ævar Arnfjörð Bjarmason <avarab@xxxxxxxxx>
Thanks-to: Johannes Schindelin <johannes.schindelin@xxxxxx>
---
Makefile | 67 +++++++++++++++++++++++-
perl/Git/I18N.pm | 2 +-
perl/header_templates/runtime_prefix.template.pl | 40 ++++++++++++++
3 files changed, 107 insertions(+), 2 deletions(-)
create mode 100644 perl/header_templates/runtime_prefix.template.pl
diff --git a/Makefile b/Makefile
index e479822ce..101a98a78 100644
--- a/Makefile
+++ b/Makefile
@@ -434,6 +434,13 @@ all::
#
# When cross-compiling, define HOST_CPU as the canonical name of the CPU on
# which the built Git will run (for instance "x86_64").
+#
+# Define RUNTIME_PREFIX to configure Git to resolve its ancillary tooling and
+# support files relative to the location of the runtime binary, rather than
+# hard-coding them into the binary. Git installations built with RUNTIME_PREFIX
+# can be moved to arbitrary filesystem locations. RUNTIME_PREFIX also causes
+# Perl scripts to use a modified entry point header allowing them to resolve
+# support files at runtime.
GIT-VERSION-FILE: FORCE
@$(SHELL_PATH) ./GIT-VERSION-GEN
@@ -471,6 +478,8 @@ ARFLAGS = rcs
# mandir
# infodir
# htmldir
+# localedir
+# perllibdir
# This can help installing the suite in a relocatable way.
prefix = $(HOME)
@@ -492,9 +501,12 @@ lib = lib
# DESTDIR =
pathsep = :
+gitexecdir_relative = $(patsubst $(prefix)/%,%,$(gitexecdir))
mandir_relative = $(patsubst $(prefix)/%,%,$(mandir))
infodir_relative = $(patsubst $(prefix)/%,%,$(infodir))
+localedir_relative = $(patsubst $(prefix)/%,%,$(localedir))
htmldir_relative = $(patsubst $(prefix)/%,%,$(htmldir))
+perllibdir_relative = $(patsubst $(prefix)/%,%,$(perllibdir))
export prefix bindir sharedir sysconfdir gitwebdir perllibdir localedir
@@ -1740,10 +1752,13 @@ mandir_relative_SQ = $(subst ','\'',$(mandir_relative))
infodir_relative_SQ = $(subst ','\'',$(infodir_relative))
perllibdir_SQ = $(subst ','\'',$(perllibdir))
localedir_SQ = $(subst ','\'',$(localedir))
+localedir_relative_SQ = $(subst ','\'',$(localedir_relative))
gitexecdir_SQ = $(subst ','\'',$(gitexecdir))
+gitexecdir_relative_SQ = $(subst ','\'',$(gitexecdir_relative))
template_dir_SQ = $(subst ','\'',$(template_dir))
htmldir_relative_SQ = $(subst ','\'',$(htmldir_relative))
prefix_SQ = $(subst ','\'',$(prefix))
+perllibdir_relative_SQ = $(subst ','\'',$(perllibdir_relative))
gitwebdir_SQ = $(subst ','\'',$(gitwebdir))
SHELL_PATH_SQ = $(subst ','\'',$(SHELL_PATH))
@@ -1754,6 +1769,31 @@ TCLTK_PATH_SQ = $(subst ','\'',$(TCLTK_PATH))
DIFF_SQ = $(subst ','\'',$(DIFF))
PERLLIB_EXTRA_SQ = $(subst ','\'',$(PERLLIB_EXTRA))
+# RUNTIME_PREFIX's resolution logic requires resource paths to be expressed
+# relative to each other and share an installation path.
+#
+# This is a dependnecy in:
+# - Git's binary RUNTIME_PREFIX logic in (see "exec_cmd.c").
+# - The runtime prefix Perl header (see
+# "perl/header_templates/runtime_prefix.template.pl").
+ifdef RUNTIME_PREFIX
+
+ifneq ($(filter /%,$(firstword $(gitexecdir_relative))),)
+$(error RUNTIME_PREFIX requires a relative gitexecdir, not: $(gitexecdir))
+endif
+
+ifneq ($(filter /%,$(firstword $(localedir_relative))),)
+$(error RUNTIME_PREFIX requires a relative localedir, not: $(localedir))
+endif
+
+ifndef NO_PERL
+ifneq ($(filter /%,$(firstword $(perllibdir_relative))),)
+$(error RUNTIME_PREFIX requires a relative perllibdir, not: $(perllibdir))
+endif
+endif
+
+endif
+
# We must filter out any object files from $(GITLIBS),
# as it is typically used like:
#
@@ -1974,10 +2014,31 @@ git.res: git.rc GIT-VERSION-FILE
# This makes sure we depend on the NO_PERL setting itself.
$(SCRIPT_PERL_GEN): GIT-BUILD-OPTIONS
+# Used for substitution in Perl modules. Disabled when using RUNTIME_PREFIX
+# since the locale directory is injected.
+perl_localedir_SQ = $(localedir_SQ)
+
ifndef NO_PERL
PERL_HEADER_TEMPLATE = perl/header_templates/fixed_prefix.template.pl
PERL_DEFINES = $(PERL_PATH_SQ):$(PERLLIB_EXTRA_SQ):$(perllibdir_SQ)
+PERL_DEFINES := $(PERL_PATH_SQ) $(PERLLIB_EXTRA_SQ) $(perllibdir_SQ)
+PERL_DEFINES += $(RUNTIME_PREFIX)
+
+# Support Perl runtime prefix. In this mode, a different header is installed
+# into Perl scripts.
+ifdef RUNTIME_PREFIX
+
+PERL_HEADER_TEMPLATE = perl/header_templates/runtime_prefix.template.pl
+
+# Don't export a fixed $(localedir) path; it will be resolved by the Perl header
+# at runtime.
+perl_localedir_SQ =
+
+endif
+
+PERL_DEFINES += $(gitexecdir) $(perllibdir) $(localedir)
+
$(SCRIPT_PERL_GEN): % : %.perl GIT-PERL-DEFINES GIT-PERL-HEADER GIT-VERSION-FILE
$(QUIET_GEN)$(RM) $@ $@+ && \
sed -e '1{' \
@@ -1990,6 +2051,7 @@ $(SCRIPT_PERL_GEN): % : %.perl GIT-PERL-DEFINES GIT-PERL-HEADER GIT-VERSION-FILE
chmod +x $@+ && \
mv $@+ $@
+PERL_DEFINES := $(subst $(space),:,$(PERL_DEFINES))
GIT-PERL-DEFINES: FORCE
@FLAGS='$(PERL_DEFINES)'; \
if test x"$$FLAGS" != x"`cat $@ 2>/dev/null`" ; then \
@@ -2005,6 +2067,9 @@ GIT-PERL-HEADER: $(PERL_HEADER_TEMPLATE) GIT-PERL-DEFINES Makefile
sed -e 's=@@PATHSEP@@=$(pathsep)=g' \
-e 's=@@INSTLIBDIR@@='$$INSTLIBDIR'=g' \
-e 's=@@PERLLIBDIR@@='$(perllibdir_SQ)'=g' \
+ -e 's=@@PERLLIBDIR_REL@@=$(perllibdir_relative_SQ)=g' \
+ -e 's=@@GITEXECDIR_REL@@=$(gitexecdir_relative_SQ)=g' \
+ -e 's=@@LOCALEDIR_REL@@=$(localedir_relative_SQ)=g' \
$< >$@+ && \
mv $@+ $@
@@ -2328,7 +2393,7 @@ endif
perl/build/lib/%.pm: perl/%.pm
$(QUIET_GEN)mkdir -p $(dir $@) && \
- sed -e 's|@@LOCALEDIR@@|$(localedir_SQ)|g' \
+ sed -e 's|@@LOCALEDIR@@|$(perl_localedir_SQ)|g' \
-e 's|@@NO_PERL_CPAN_FALLBACKS@@|$(NO_PERL_CPAN_FALLBACKS_SQ)|g' \
< $< > $@
diff --git a/perl/Git/I18N.pm b/perl/Git/I18N.pm
index dba96fff0..bfb4fb67a 100644
--- a/perl/Git/I18N.pm
+++ b/perl/Git/I18N.pm
@@ -18,7 +18,7 @@ our @EXPORT_OK = @EXPORT;
sub __bootstrap_locale_messages {
our $TEXTDOMAIN = 'git';
- our $TEXTDOMAINDIR = $ENV{GIT_TEXTDOMAINDIR} || '@@LOCALEDIR@@';
+ our $TEXTDOMAINDIR ||= $ENV{GIT_TEXTDOMAINDIR} || '@@LOCALEDIR@@';
require POSIX;
POSIX->import(qw(setlocale));
diff --git a/perl/header_templates/runtime_prefix.template.pl b/perl/header_templates/runtime_prefix.template.pl
new file mode 100644
index 000000000..a18913967
--- /dev/null
+++ b/perl/header_templates/runtime_prefix.template.pl
@@ -0,0 +1,40 @@
+# BEGIN RUNTIME_PREFIX generated code.
+#
+# This finds our Git::* libraries relative to the script's runtime path.
+sub __git_system_path {
+ my ($relpath) = @_;
+ my $gitexecdir_relative = '@@GITEXECDIR_REL@@';
+
+ # GIT_EXEC_PATH is supplied by `git` or the test suite.
+ my $exec_path = $ENV{GIT_EXEC_PATH};
+ if ($exec_path eq "") {
+ # This can happen if this script is being directly invoked instead of run
+ # by "git".
+ require FindBin;
+ $exec_path = $FindBin::Bin;
+ }
+
+ # Trim off the relative gitexecdir path to get the system path.
+ (my $prefix = $exec_path) =~ s=${gitexecdir_relative}$==;
+
+ require File::Spec;
+ return File::Spec->catdir($prefix, $relpath);
+}
+
+BEGIN {
+ use lib split /@@PATHSEP@@/,
+ (
+ $ENV{GITPERLLIB} ||
+ do {
+ my $perllibdir = __git_system_path('@@PERLLIBDIR_REL@@');
+ (-e $perllibdir) || die("Invalid system path ($relpath): $path");
+ $perllibdir;
+ }
+ );
+
+ # Export the system locale directory to the I18N module. The locale directory
+ # is only installed if NO_GETTEXT is set.
+ $Git::I18N::TEXTDOMAINDIR = __git_system_path('@@LOCALEDIR_REL@@');
+}
+
+# END RUNTIME_PREFIX generated code.
--
2.15.0.chromium12
