From 209576016144d331e4329c772989ef19d2e5c961 Mon Sep 17 00:00:00 2001
From: Pierre Pronchery <khorben@defora.org>
Date: Mon, 24 Feb 2020 02:40:28 +0100
Subject: [PATCH] Import a new helper for job management

This currently depends on DeforaOS libDatabase.
---
 src/deforaos-jobs.sh | 197 +++++++++++++++++++++++++++++++++++++++++++
 src/project.conf     |   6 +-
 2 files changed, 202 insertions(+), 1 deletion(-)
 create mode 100755 src/deforaos-jobs.sh

diff --git a/src/deforaos-jobs.sh b/src/deforaos-jobs.sh
new file mode 100755
index 0000000..53185ae
--- /dev/null
+++ b/src/deforaos-jobs.sh
@@ -0,0 +1,197 @@
+#!/bin/sh
+#Copyright (c) 2020 Pierre Pronchery <khorben@defora.org>
+#Error codes:
+#  1	Usage error
+#  2	Generic error
+#  3	Could not lock the database
+#  4	Could not unlock the database
+
+
+
+#variables
+DATABASE_CONFFILE="deforaos-jobs.conf"
+DATABASE_ENGINE="sqlite3"
+DATABASE_FILE="deforaos-jobs.db"
+DATABASE_INITFILE="deforaos-jobs.sql"
+DEVNULL="/dev/null"
+PROGNAME_JOBS="defora-jobs"
+QUERY_ADD_BEGIN="INSERT INTO jobs (command) VALUES ('"
+QUERY_ADD_END="')"
+QUERY_EXEC_SELECT="SELECT jobs_id, command FROM jobs WHERE started IS NULL ORDER BY jobs_id ASC LIMIT 1"
+QUERY_INIT="CREATE TABLE jobs (jobs_id INTEGER PRIMARY KEY, timestamp TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP, command VARCHAR(255), started TIMESTAMP DEFAULT NULL, pid INTEGER DEFAULT NULL, code INTEGER DEFAULT NULL, completed TIMESTAMP DEFAULT NULL)"
+QUERY_LIST="SELECT * FROM jobs"
+#executables
+DATABASE="database"
+DEBUG=
+LOCK="mkdir"
+UNLOCK="rmdir"
+SED="sed"
+
+
+#functions
+#database_add
+_database_add()
+{
+	if [ $# -ne 1 ]; then
+		_usage
+		return $?
+	fi
+	command="$1"
+	query="$QUERY_ADD_BEGIN$(echo "$command" | _database_escape)$QUERY_ADD_END"
+
+	_database_init						|| return 2
+	_database_query "$query" > "$DEVNULL"			|| return 2
+}
+
+
+#database_escape
+_database_escape()
+{
+	$SED -e "s,','',"
+}
+
+
+#database_exec
+_database_exec()
+{
+	if [ $# -ne 0 ]; then
+		_usage
+		return $?
+	fi
+
+	_database_init						|| return 2
+	_database_lock						|| return 3
+	_database_query "$QUERY_EXEC_SELECT" | (IFS="|"
+	read header
+	read empty jobs_id command empty
+	if [ -z "$jobs_id" ]; then
+		_database_unlock				|| return 4
+		return 0
+	fi
+	#XXX TOCTOU
+	QUERY="UPDATE jobs SET started=datetime() WHERE jobs_id='$jobs_id'"
+	_database_query "$QUERY" > "$DEVNULL"
+	_database_unlock
+	code=-1
+	if [ -n "$command" ]; then
+		$DEBUG sh -c "$command" &
+		pid=$!
+		QUERY="UPDATE jobs SET pid='$pid' WHERE jobs_id='$jobs_id'"
+		_database_query "$QUERY" > "$DEVNULL"
+		wait $pid
+		code=$?
+	fi
+	QUERY="UPDATE jobs SET completed=datetime(), code='$code' WHERE jobs_id='$jobs_id'"
+	_database_query "$QUERY" > "$DEVNULL")
+}
+
+
+#database_init
+_database_init()
+{
+	if [ ! -f "$DATABASE_CONFFILE" ]; then
+		echo "filename=$DATABASE_FILE" > "$DATABASE_CONFFILE"
+	fi
+	if [ ! -f "$DATABASE_FILE" ]; then
+		_database_lock					|| return 3
+		_database_query "$QUERY_INIT" > "$DEVNULL"	|| return 2
+		_database_unlock				|| return 4
+	fi
+	return 0
+}
+
+
+#database_list
+_database_list()
+{
+	if [ $# -ne 0 ]; then
+		_usage
+		return $?
+	fi
+	_database_init						|| return 2
+	_database_query "$QUERY_LIST"				|| return 2
+}
+
+
+#database_lock
+_database_lock()
+{
+	$DEBUG $LOCK "${DATABASE_FILE%.db}"
+}
+
+
+#database_query
+_database_query()
+{
+	$DEBUG $DATABASE -d "$DATABASE_ENGINE" -C "$DATABASE_CONFFILE" "$@"
+}
+
+
+#database_unlock
+_database_unlock()
+{
+	$DEBUG $UNLOCK "${DATABASE_FILE%.db}"
+}
+
+
+#debug
+_debug()
+{
+	echo "$@" 1>&3
+	"$@"
+}
+
+
+#error
+_error()
+{
+	echo "$PROGNAME_JOBS: $@" 1>&2
+	return 2
+}
+
+
+#usage
+_usage()
+{
+	echo "Usage: $PROGNAME_JOBS add command" 1>&2
+	echo "       $PROGNAME_JOBS list" 1>&2
+	echo "       $PROGNAME_JOBS exec" 1>&2
+	return 1
+}
+
+
+#main
+while getopts "DO:" name; do
+	case "$name" in
+		D)
+			DEBUG="_debug"
+			;;
+		O)
+			export "${OPTARG%%=*}"="${OPTARG#*=}"
+			;;
+		?)
+			_usage
+			exit $?
+			;;
+	esac
+done
+shift $((OPTIND - 1))
+if [ $# -lt 1 ]; then
+	_usage
+	exit $?
+fi
+
+exec 3>&1
+
+method="_usage"
+case "$1" in
+	add|list|exec)
+		method="_database_$1"
+		;;
+	*)
+		_error "$1: Operation not supported"
+		;;
+esac
+shift
+
+"$method" "$@"
diff --git a/src/project.conf b/src/project.conf
index 16cd355..f8eaab9 100644
--- a/src/project.conf
+++ b/src/project.conf
@@ -1,4 +1,4 @@
-dist=Makefile,deforaos-build.sh,deforaos-document.sh,deforaos-git-hook.sh,deforaos-git-message.sh,deforaos-irc.sh,deforaos-lock.sh,deforaos-package.sh,deforaos-release.sh,deforaos-update.sh
+dist=Makefile,deforaos-build.sh,deforaos-document.sh,deforaos-git-hook.sh,deforaos-git-message.sh,deforaos-irc.sh,deforaos-jobs.sh,deforaos-lock.sh,deforaos-package.sh,deforaos-release.sh,deforaos-update.sh
 
 [deforaos-build.sh]
 install=$(PREFIX)/bin
@@ -20,6 +20,10 @@ mode=0755
 install=$(PREFIX)/libexec
 mode=0755
 
+[deforaos-jobs.sh]
+install=$(PREFIX)/bin
+mode=0755
+
 [deforaos-lock.sh]
 install=$(PREFIX)/bin
 mode=0755