build: pull authors out of subrepos

 - pulls comitternames out of subrepos
 - uses local variables instead of globals
 - makes use of our .mailmap file in our main repo
 - composable: just source it and pipe it into your process

usage in `couchdb-build-release.sh`:

```sh
sed -e "/^#.*/d" THANKS.in > $RELDIR/THANKS

source "build-aux/print-committerlist.sh"
print_comitter_list >> THANKS;
```

1 files changed, 68 insertions, 0 deletions

diff --git a/build-aux/print-committerlist.sh b/build-aux/print-committerlist.sh
new file mode 100755
index 000000000..7fbb96b7f
--- /dev/null
+++ b/build-aux/print-committerlist.sh
@@ -0,0 +1,68 @@
+#!/bin/sh
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may not
+# use this file except in compliance with the License. You may obtain a copy of
+# the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations under
+# the License.
+
+function get_contributors {
+  local OS=`uname -s`
+  case "$OS" in
+  Linux|CYGWIN*) # GNU sed
+    local SED_ERE_FLAG=-r
+  ;;
+  *) # BSD sed
+    local SED_ERE_FLAG=-E
+  ;;
+  esac
+
+  local CONTRIB_EMAIL_SED_COMMAND="s/^[[:blank:]]{5}[[:digit:]]+[[:blank:]]/ * /"
+  if [ "$1" == "couchdb-main-repo" ]
+  then
+    git shortlog -se 6c976bd..HEAD \
+      | grep -v @apache.org \
+      | sed $SED_ERE_FLAG -e "$CONTRIB_EMAIL_SED_COMMAND"
+  else
+    cd src/$1
+    git shortlog -se HEAD \
+      | grep -v @apache.org \
+      | sed $SED_ERE_FLAG -e "$CONTRIB_EMAIL_SED_COMMAND"
+    cd .. && cd ..
+  fi
+}
+
+function print_comitter_list {
+  # list of external repos that we exclude
+  local EXCLUDE=("bear" "folsom" "goldrush" "ibrowse" "jiffy" "lager" "meck" "mochiweb" "oauth" "snappy")
+  local EXCLUDE=$(printf "\|%s" "${EXCLUDE[@]}")
+  local EXCLUDE=${EXCLUDE:2}
+  local SUBREPOS=$(ls src/ | grep -v "$EXCLUDE")
+
+  if test -e .git; then
+
+    {
+      for i in $SUBREPOS; do
+        get_contributors $i
+      done;
+      get_contributors "couchdb-main-repo"
+    } | git check-mailmap --stdin | awk '
+      BEGIN {
+      }
+      {
+        $1 = "";
+        persons[$0] = $0;
+      }
+      END {
+        for (i in persons) {
+          print persons[i];
+        }
+      }'
+  fi
+}