Allow user-specified programs to override system-installed ones

(manually tested)

  - new rc var: GL_BINDIR2; see doc update in this commit

  - added _which() function to search both $GL_BINDIR and $GL_BINDIR2
  - 'gitolite <command>', non-perl triggers, VREFs, and sugar, use this

  - unshifted $GL_BINDIR2/lib into @INC upfront in Rc.pm
  - perl triggers use this

doc/rc.mkd

@@ -97,3 +97,25 @@ information.
     require the '@' to be escaped:
 
         DEFAULT_ROLE_PERMS  =>  "READERS \@all\nWRITERS \@senior_devs",
+
+  * `GL_BINDIR2`, string
+
+    This is useful when you install gitolite system-wide, but want to add or
+    override commands, VREFs, triggers, etc., by putting them somewhere in the
+    hosting user's home directory (i.e., without requiring root privileges).
+
+    Add a new variable `GL_BINDIR2` to the the rc file.  Example:
+
+        GL_BINDIR2 => "$ENV{HOME}/gitolite/src2",
+
+    In that directory, create as much of the following directory structure as
+    you need to add your programs:
+
+        .
+        |-- commands
+        |-- lib
+        |   `-- Gitolite
+        |       `-- Triggers
+        |-- syntactic-sugar
+        |-- triggers
+        `-- VREF

src/gitolite

@@ -73,9 +73,10 @@ if ( $command eq 'setup' ) {
 } elsif ( $command eq 'trigger' ) {
     trigger(@args);
 
-} elsif ( -x "$rc{GL_BINDIR}/commands/$command" ) {
-    trace( 2, "attempting gitolite command $command" );
-    run_command( $command, @args );
+} elsif ( my $c = _which("commands/$command", 'x' ) ) {
+    trace( 2, "attempting gitolite command $c" );
+    _system( $c, @args );
+    exit 0;
 
 } elsif ( $command eq 'list-phy-repos' ) {
     _chdir( $rc{GL_REPO_BASE} );
@@ -99,11 +100,3 @@ sub args {
 }
 
 # ----------------------------------------------------------------------
-
-sub run_command {
-    my $pgm      = shift;
-    my $fullpath = "$ENV{GL_BINDIR}/commands/$pgm";
-    _die "'$pgm' not found or not executable" if not -x $fullpath;
-    _system( $fullpath, @_ );
-    exit 0;
-}

src/lib/Gitolite/Conf/Sugar.pm

@@ -52,7 +52,7 @@ sub sugar {
                 # perl-ism; apart from keeping the full path separate from the
                 # simple name, this also protects %rc from change by implicit
                 # aliasing, which would happen if you touched $s itself
-                my $sfp = "$ENV{GL_BINDIR}/syntactic-sugar/$s";
+                my $sfp = _which("syntactic-sugar/$s", 'r');
 
                 _warn("skipped sugar script '$s'"), next if not -r $sfp;
                 $lines = SugarBox::run_sugar_script( $sfp, $lines );

src/lib/Gitolite/Hooks/Update.pm

@@ -61,8 +61,8 @@ sub check_vrefs {
             }
         } else {
             my ( $dummy, $pgm, @args ) = split '/', $vref;
-            $pgm = "$ENV{GL_BINDIR}/VREF/$pgm";
-            -x $pgm or _die "'$vref': helper program missing or unexecutable";
+            $pgm = _which("VREF/$pgm", 'x');
+            $pgm or _die "'$vref': helper program missing or unexecutable";
 
             open( my $fh, "-|", $pgm, @_, $vref, @args ) or _die "'$vref': can't spawn helper program: $!";
             while (<$fh>) {

src/lib/Gitolite/Rc.pm

@@ -9,6 +9,7 @@ package Gitolite::Rc;
   query_rc
   version
   trigger
+  _which
 
   $REMOTE_COMMAND_PATT
   $REF_OR_FILENAME_PATT
@@ -83,9 +84,11 @@ unshift @{ $rc{ACCESS_1} }, 'Writable::access_1';
 # use an env var that is highly unlikely to appear in real life :)
 do $ENV{G3T_RC} if exists $ENV{G3T_RC} and -r $ENV{G3T_RC};
 
-# fix some env vars, setup gitolite internal "env" vars (aka rc vars)
+# setup some perl/rc/env vars
 # ----------------------------------------------------------------------
 
+unshift @INC, "$rc{GL_BINDIR2}/lib" if $rc{GL_BINDIR2};
+
 $ENV{PATH} = "$ENV{GL_BINDIR}:$ENV{PATH}";
 
 {
@@ -215,9 +218,9 @@ sub trigger {
                     Gitolite::Triggers::run( $module, $sub, @args, $rc_section, @_ );
 
                 } else {
-                    $pgm = "$ENV{GL_BINDIR}/triggers/$pgm";
+                    $pgm = _which("triggers/$pgm", 'x');
 
-                    _warn("skipped command '$s'"), next if not -x $pgm;
+                    _warn("skipped command '$s'"), next if not $pgm;
                     trace( 2, "command: $s" );
                     _system( $pgm, @args, $rc_section, @_ );    # they better all return with 0 exit codes!
                 }
@@ -228,6 +231,23 @@ sub trigger {
     trace( 2, "'$rc_section' not found in rc" );
 }
 
+sub _which {
+    # looks for a file in GL_BINDIR2 or GL_BINDIR.  Returns whichever exists
+    # (GL_BINDIR2 preferred if defined) or 0 if not found.
+    my $file = shift;
+    my $mode = shift;   # could be 'x' or 'r'
+
+    my @files = ("$rc{GL_BINDIR}/$file");
+    unshift @files, ("$rc{GL_BINDIR2}/$file") if $rc{GL_BINDIR2};
+
+    for my $f ( @files ) {
+        return $f if -x $f;
+        return $f if -r $f and $mode eq 'r';
+    }
+
+    return 0;
+}
+
 # ----------------------------------------------------------------------
 
 =for args