[PATCH] checkpatch: fix can't check for too long invalid commit id

[Wang YanQing]

The current UNKNOWN_COMMIT_ID doesn't check for 41+ length commit id,
and although GIT_COMMIT_ID will check for 41+ length commit id, but
it willn't warn anything about it due to 41+ length commit will never
be defined.

This patch moves the unknown commit id check for normal commit description
to GIT_COMMIT_ID, and uses ERROR instead of WARN, because unknown commit
id is total useless to track change history in changelog, it deserves the
ERROR.

Signed-off-by: Wang YanQing <udkni...@gmail.com>
---
 After this patch, in another patch 'checkpatch: add support to check 'Fixes:' 
tag format',
 I will delete UNKNOWN_COMMIT_ID, because we don't need it anymore after 
GIT_COMMIT_ID could
 do the same check as UNKNOWN_COMMIT_ID for 'Fixes:' tag.

 scripts/checkpatch.pl | 14 ++++++++++++--
 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/scripts/checkpatch.pl b/scripts/checkpatch.pl
index 23a001a..143bb43 100755
--- a/scripts/checkpatch.pl
+++ b/scripts/checkpatch.pl
@@ -2865,8 +2865,18 @@ sub process {
                        ($id, $description) = git_commit_info($orig_commit,
                                                              $id, $orig_desc);
 
+                       if (!defined($id)) {
+                           if ($long) {
+                               ERROR("GIT_COMMIT_ID",
+                                     "Unknown commit id '$orig_commit' is too 
long, maybe misspelled?\n" . $herecurr);
+                           } else {
+                               ERROR("GIT_COMMIT_ID",
+                                     "Unknown commit id '$orig_commit', maybe 
rebased or not pulled?\n" . $herecurr);
+                           }
+                       }
+
                        if (defined($id) &&
-                          ($short || $long || $space || $case || ($orig_desc 
ne $description) || !$hasparens)) {
+                          ($short || $space || $case || ($orig_desc ne 
$description) || !$hasparens)) {
                                ERROR("GIT_COMMIT_ID",
                                      "Please use git commit description style 
'commit <12+ chars of sha1> (\"<title line>\")' - ie: '${init_char}ommit $id 
(\"$description\")'\n" . $herecurr);
                        }
@@ -2969,7 +2979,7 @@ sub process {
                }
 
 # check for invalid commit id
-               if ($in_commit_log && $line =~ 
/(^fixes:|\bcommit)\s+([0-9a-f]{6,40})\b/i) {
+               if ($in_commit_log && $line =~ 
/(^fixes:)\s+([0-9a-f]{6,40})\b/i) {
                        my $id;
                        my $description;
                        ($id, $description) = git_commit_info($2, undef, undef);
-- 
1.8.5.6.2.g3d8a54e.dirty