checkpatch: improve --git <commit-count> shortcut

The --git <commit-count> shortcut can be confused by a tag with a dash
like v4.4-rc1.

Improve the test to verify the <commit-count> expression ends with a
dash followed by a numeric value.

Improve the git log result to verify the "<sha1> <subject>" output
as well.

Link: http://lkml.kernel.org/r/c4a3f759291d967641860c3a54bb81177f34325f.1462711962.git.joe@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 4 insertions, 6 deletions

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 928366215fc5..6750595bd7b8 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -809,11 +809,8 @@ if ($git) {
         my @commits = ();
         foreach my $commit_expr (@ARGV) {
                 my $git_range;
-                if ($commit_expr =~ m/-/) {
-                        my @tmp = split(/-/, $commit_expr);
-                        die "$P: incorrect git commit expression '$commit_expr' $!\n"
-                            if (@tmp != 2);
-                        $git_range = "-$tmp[1] $tmp[0]";
+                if ($commit_expr =~ m/^(.*)-(\d+)$/) {
+                        $git_range = "-$2 $1";
                 } elsif ($commit_expr =~ m/\.\./) {
                         $git_range = "$commit_expr";
                 } else {
@@ -821,7 +818,8 @@ if ($git) {
                 }
                 my $lines = `git log --no-color --no-merges --pretty=format:'%H %s' $git_range`;
                 foreach my $line (split(/\n/, $lines)) {
-                        $line =~ /(^\w+) (.*)/;
+                        $line =~ /^([0-9a-fA-F]{40,40}) (.*)$/;
+                        next if (!defined($1) || !defined($2));
                         my $sha1 = $1;
                         my $subject = $2;
                         unshift(@commits, $sha1);