Git.pm: Call external commands using execv_git_cmd()

Instead of explicitly using the git wrapper to call external commands,
use the execv_git_cmd() function which will directly call whatever
needs to be called. GitBin option becomes useless so drop it.

This actually means the exec_path() thing I planned to use worthless
internally, but Jakub wants it in anyway and I don't mind, so...
Signed-off-by: NPetr Baudis <pasky@suse.cz>
Signed-off-by: NJunio C Hamano <junkio@cox.net>

perl/Git.pm

@@ -122,9 +122,6 @@ =head1 CONSTRUCTORS
 If the directory does not have the subdirectory, C<WorkingCopy> is left
 undefined and C<Repository> is pointed to the directory itself.
 
-B<GitPath> - Path to the C<git> binary executable. By default the C<$PATH>
-is searched for it.
-
 You should not use both C<Directory> and either of C<Repository> and
 C<WorkingCopy> - the results of that are undefined.
 
@@ -363,11 +360,14 @@ sub _cmd_exec {
 		$self->{opts}->{Repository} and $ENV{'GIT_DIR'} = $self->{opts}->{Repository};
 		$self->{opts}->{WorkingCopy} and chdir($self->{opts}->{WorkingCopy});
 	}
-	my $git = $self->{opts}->{GitPath};
-	$git ||= 'git';
-	exec ($git, @args) or croak "exec failed: $!";
+	xs__execv_git_cmd(@args);
+	croak "exec failed: $!";
 }
 
+# Execute the given Git command ($_[0]) with arguments ($_[1..])
+# by searching for it at proper places.
+# _execv_git_cmd(), implemented in Git.xs.
+
 # Close pipe to a subprocess.
 sub _cmd_close {
 	my ($fh) = @_;

perl/Git.xs

@@ -33,6 +33,28 @@ OUTPUT:
 	RETVAL
 
 
+void
+xs__execv_git_cmd(...)
+CODE:
+{
+	const char **argv;
+	int i;
+
+	argv = malloc(sizeof(const char *) * (items + 1));
+	if (!argv)
+		croak("malloc failed");
+	for (i = 0; i < items; i++)
+		argv[i] = strdup(SvPV_nolen(ST(i)));
+	argv[i] = NULL;
+
+	execv_git_cmd(argv);
+
+	for (i = 0; i < items; i++)
+		if (argv[i])
+			free((char *) argv[i]);
+	free((char **) argv);
+}
+
 char *
 xs_hash_object(file, type = "blob")
 	SV *file;