Add support for modifying all components of pack job

When the "scontrol update jobid=#" command specifies a pack job
leader, then modify all components of the pack job. To modiify only
the pack job leader, specify "scontrol update jobid=#+0".

doc/html/heterogeneous_jobs.shtml

@@ -223,7 +223,7 @@ $ squeue --job=93
 JOBID PARTITION  NAME  USER ST  TIME  NODES NODELIST
 </pre>
 
-<pWhile a heterogeneous job is in pending state, only the entire job can be
+<p>While a heterogeneous job is in pending state, only the entire job can be
 cancelled rather than it's individual components.
 A request to cancel an individual component of a heterogeneous job not in
 pending state will return an error.
@@ -233,6 +233,19 @@ After the job has begun execution, the individual component can be cancelled.</p
 is only supported for a pack leader. Requests for email notifications for other
 components of a heterogeneous job will be silently ignored.</p>
 
+<p>Requests to modify an individual component of a job using the scontrol
+command must specify the job ID with the "#+#" notation.
+A request to modify a job by specifying the pack_job_id will modify all
+components of a heterogeneous job.
+For example:</p>
+<pre>
+# Change the account of compnent 2 of heterogeneous job 123:
+$ scontrol update jobid=123+2 account=abc
+
+# Change the time limit of all components of heterogeneous job 123:
+$ scontrol update jobid=123 timelimit=60
+</pre>
+
 <p>Requests to perform the following operations a job can only be requested for
 a pack leader and will be applied to all components of that heterogeneous job.
 Requests to operate on individual components of the heterogeneous will return
@@ -470,6 +483,6 @@ especially other heterogeneous jobs.</p>
 
 <p class="footer"><a href="#top">top</a></p>
 
-<p style="text-align:center;">Last modified 11 August 2017</p>
+<p style="text-align:center;">Last modified 14 August 2017</p>
 
 <!--#include virtual="footer.txt"-->

src/slurmctld/job_mgr.c

@@ -12767,9 +12767,11 @@ extern int update_job(slurm_msg_t *msg, uid_t uid, bool send_msg)
  */
 extern int update_job_str(slurm_msg_t *msg, uid_t uid)
 {
+
 	slurm_msg_t resp_msg;
 	job_desc_msg_t *job_specs = (job_desc_msg_t *) msg->data;
-	struct job_record *job_ptr, *new_job_ptr;
+	struct job_record *job_ptr, *new_job_ptr, *pack_job;
+	ListIterator iter;
 	long int long_id;
 	uint32_t job_id = 0, pack_offset;
 	bitstr_t *array_bitmap = NULL, *tmp_bitmap;
@@ -12799,6 +12801,20 @@ extern int update_job_str(slurm_msg_t *msg, uid_t uid)
 	if (end_ptr[0] == '\0') {	/* Single job (or full job array) */
 		struct job_record *job_ptr_done = NULL;
 		job_ptr = find_job_record(job_id);
+		if (job_ptr && job_ptr->pack_job_list) {
+			iter = list_iterator_create(job_ptr->pack_job_list);
+			while ((pack_job = list_next(iter))) {
+				if (job_ptr->pack_job_id !=
+				    pack_job->pack_job_id) {
+					error("%s: Bad pack_job_list for job %u",
+					      __func__, job_ptr->pack_job_id);
+					continue;
+				}
+				rc = _update_job(pack_job, job_specs, uid);
+			}
+			list_iterator_destroy(iter);
+			goto reply;
+		}
 		if (job_ptr &&
 		    (((job_ptr->array_task_id == NO_VAL) &&
 		      (job_ptr->array_recs == NULL)) ||
@@ -12842,7 +12858,7 @@ extern int update_job_str(slurm_msg_t *msg, uid_t uid)
 		goto reply;
 	} else if (end_ptr[0] == '+') {	/* Pack job element */
 		long_id = strtol(end_ptr+1, &tmp, 10);
-		if ((long_id <= 0) || (long_id == LONG_MAX) ||
+		if ((long_id < 0) || (long_id == LONG_MAX) ||
 		    (tmp[0] != '\0')) {
 			info("%s: invalid job id %s", __func__, job_id_str);
 			rc = ESLURM_INVALID_JOB_ID;