Dgit.pm: Provide hashfile()

[dgit.git] / Debian / Dgit.pm

diff --git a/Debian/Dgit.pm b/Debian/Dgit.pm
index a453f352718b33a5567e040cdd9302973c40b279..2555812c46abcdd1c617e718b0cb1c5643e8e0ba 100644 (file)
--- a/Debian/Dgit.pm
+++ b/Debian/Dgit.pm
@@ -8,6 +8,7 @@ use warnings;
 use POSIX;
 use IO::Handle;
 use Config;
+use Digest::SHA;
 
 BEGIN {
     use Exporter   ();
@@ -17,7 +18,10 @@ BEGIN {
     @ISA         = qw(Exporter);
     @EXPORT      = qw(setup_sigwarn
                       debiantag server_branch server_ref
-                      stat_exists fail ensuredir waitstatusmsg failedcmd
+                      stat_exists link_ltarget
+                     hashfile
+                      fail ensuredir executable_on_path
+                      waitstatusmsg failedcmd
                       cmdoutput cmdoutput_errok
                       git_rev_parse git_get_ref git_for_each_ref
                       git_for_each_tag_referring is_fast_fwd
@@ -153,6 +157,17 @@ sub ensuredir ($) {
     die "mkdir $dir: $!";
 }
 
+sub executable_on_path ($) {
+    my ($program) = @_;
+    return 1 if $program =~ m{/};
+    my @path = split /:/, ($ENV{PATH} // "/usr/local/bin:/bin:/usr/bin");
+    foreach my $pe (@path) {
+       my $here = "$pe/$program";
+       return $here if stat_exists $here && -x _;
+    }
+    return undef;
+}
+
 our @signames = split / /, $Config{sig_name};
 
 sub waitstatusmsg () {
@@ -184,7 +199,7 @@ sub failedcmd {
 sub cmdoutput_errok {
     die Dumper(\@_)." ?" if grep { !defined } @_;
     debugcmd "|",@_;
-    open P, "-|", @_ or die $!;
+    open P, "-|", @_ or die "$_[0] $!";
     my $d;
     $!=0; $?=0;
     { local $/ = undef; $d = <P>; }
@@ -207,6 +222,22 @@ sub cmdoutput {
     return $d;
 }
 
+sub link_ltarget ($$) {
+    my ($old,$new) = @_;
+    lstat $old or return undef;
+    if (-l _) {
+       $old = cmdoutput qw(realpath  --), $old;
+    }
+    link $old, $new or die "link $old $new: $!";
+}
+
+sub hashfile ($) {
+    my ($fn) = @_;
+    my $h = Digest::SHA->new(256);
+    $h->addfile($fn);
+    return $h->hexdigest();
+}
+
 sub git_rev_parse ($) {
     return cmdoutput qw(git rev-parse), "$_[0]~0";
 }