[PATCH 10/10] Add -s option to show log summary

[Jonas Fonseca <fonseca@diku.dk>]

When passing -s to cg-log each log entry is summarized in one line. The line
carries info about commit date, author, first log line and the commit id. It
will look something like the following (with only:

  2005-05-20 11:46 Linus Torvalds   sparse cleanup   e99d59ff0bff349ef20...

The result ends up being 130 chars wide however the commit id is placed so
that it can easily be hidden if line wrapping in the pager is enabled.

Signed-off-by: Jonas Fonseca <fonseca@diku.dk>
---

 cg-Xlib |    4 +++-
 cg-log  |   53 ++++++++++++++++++++++++++++++++++++++++++++---------
 2 files changed, 47 insertions(+), 10 deletions(-)

diff --git a/cg-Xlib b/cg-Xlib
--- a/cg-Xlib
+++ b/cg-Xlib
@@ -47,10 +47,12 @@ mktemp () {
 
 showdate () {
 	date="$1"
+	format="$2"
+	[ "$format" ] || format=-R
 	sec=${date[0]}; tz=${date[1]}
 	dtz=${tz/+/}
 	lsec=$(expr $dtz / 100 \* 3600 + $dtz % 100 \* 60 + $sec)
-	pdate="$(date -Rud "1970-01-01 UTC + $lsec sec" 2>/dev/null)"
+	pdate="$(date -ud "1970-01-01 UTC + $lsec sec" "$format" 2>/dev/null)"
 
 	echo "${pdate/+0000/$tz}"
 }
diff --git a/cg-log b/cg-log
--- a/cg-log
+++ b/cg-log
@@ -14,15 +14,21 @@
 # cg-log then displays only changes in those files.
 #
 # -c::
-#	Add color to the output. Currently, the colors are:
-#	- `author`:	'cyan'
-#	- `committer`:	'magenta'
-#	- `header`:	'green'
-#	- `files`:	'blue'
-#	- `signoff`:	'yellow'
+#	Colorize to the output. When getting log summary the `date` is
+#	colored 'green', the `author` is colored 'cyan', the `commit ID`
+#	is colored 'blue' and the special line trimming character (~) is
+#	colored 'magenta'. +
+#	+
+#	When getting the full log the colors are:
+#		- `author`:	'cyan'
+#		- `committer`:	'magenta'
+#		- `header`:	'green'
+#		- `files`:	'blue'
+#		- `signoff`:	'yellow'
 #
 # -f::
-#	List affected files.
+#	List affected files. This option does not make sense when using
+#	`-s` to get a log summary.
 #
 # -r FROM_ID[:TO_ID]::
 #	Limit the log information to a set of revisions using either
@@ -36,6 +42,12 @@
 #	End the log listing at the merge base of the -r arguments
 #	(defaulting to master and origin).
 #
+# -s::
+#	Show a one line summary for each log entry. The summary contains
+#	information about the commit date, the author, the first line
+#	of the commit log and the commit ID. Long author and commit log
+#	titles are trimmed but marked with an ending tilde (~).
+#
 # -uUSERNAME::
 #	List only commits where author or committer contains 'USERNAME'.
 #	The search for 'USERNAME' is case-insensitive.
@@ -55,7 +67,7 @@
 #
 #	$ cg-log -r releasetag-0.9:releasetag-0.10
 
-USAGE="cg-log [-c] [-f] [m] [-uUSERNAME] [-r FROM_ID[:TO_ID] FILE..."
+USAGE="cg-log [-c] [-f] [-m] [-s] [-uUSERNAME] [-r FROM_ID[:TO_ID] FILE..."
 
 . ${COGITO_LIB}cg-Xlib
 # Try to fix the annoying "Broken pipe" output. May not help, but apparently
@@ -71,6 +83,7 @@ coldefault=
 list_files=
 log_start=
 log_end=
+summary=
 user=
 mergebase=
 files=()
@@ -107,6 +120,9 @@ while [ "$1" ]; do
 	-m)
 		mergebase=1
 		;;
+	-s)
+		summary=1
+		;;
 	*)
 		files=("$@")
 		break
@@ -196,6 +212,8 @@ print_commit_log() {
 					echo -e "author $author\ncommitter $committer" \
 						| grep -qi "$user" || return
 				fi
+				[ "$summary" ] && continue
+
 				echo ${colheader}commit ${commit%:*} $coldefault
 				echo ${colheader}tree $tree $coldefault
 
@@ -222,6 +240,23 @@ print_commit_log() {
 					s/./    &/
 				'
 				;;
+			*)
+				# Print summary
+				author="${author% <*}"
+				date=(${committer#*> })
+				date="$(showdate $date '+%F %H:%M')"
+				title="$key $rest"
+				if [ "${#title}" -gt 51 ]; then
+					title="${title:0:50}$colcommitter~"
+				fi
+				if [ "${#author}" -gt 20 ]; then
+					author="${author:0:19}$colcommitter~"
+				fi
+
+				printf "$colheader$date $colauthor%-20s $coldefault%-51s $colfiles${commit%:*}$coldefault\n" \
+					"$author" "$title"
+				return
+				;;
 			esac
 		done
 }
@@ -232,6 +267,6 @@ $revls | $revsort | while read time comm
 	log="$(print_commit_log $commit)"
 	if [ "$log" ]; then
 		echo "$log"
-		echo
+		[ "$summary" ] || echo
 	fi
 done | pager
-- 
Jonas Fonseca