patch 8.1.0863: cannot see what signal caused a job to end

Problem:    Cannot see what signal caused a job to end.
Solution:   Add "termsig" to job_info(). (Ozaki Kiichi, closes #3786)

runtime/doc/eval.txt

@@ -5745,6 +5745,11 @@ job_info([{job}])					*job_info()*
 		   "exit_cb"	function to be called on exit
 		   "stoponexit"	|job-stoponexit|
 
+		   Only in Unix:
+		   "termsig"	the signal which terminated the process
+				(See |job_stop()| for the values)
+				only valid when "status" is "dead"
+
 		Without any arguments, returns a List with all Job objects.
 
 job_setoptions({job}, {options})			*job_setoptions()*

src/channel.c

@@ -5152,6 +5152,9 @@ job_free_contents(job_T *job)
     vim_free(job->jv_tty_in);
     vim_free(job->jv_tty_out);
     vim_free(job->jv_stoponexit);
+#ifdef UNIX
+    vim_free(job->jv_termsig);
+#endif
     free_callback(job->jv_exit_cb, job->jv_exit_partial);
     if (job->jv_argv != NULL)
     {
@@ -5908,6 +5911,9 @@ job_info(job_T *job, dict_T *dict)
     dict_add_number(dict, "exitval", job->jv_exitval);
     dict_add_string(dict, "exit_cb", job->jv_exit_cb);
     dict_add_string(dict, "stoponexit", job->jv_stoponexit);
+#ifdef UNIX
+    dict_add_string(dict, "termsig", job->jv_termsig);
+#endif
 
     l = list_alloc();
     if (l != NULL)

src/os_unix.c

@@ -5655,6 +5655,23 @@ failed:
 	close(pty_slave_fd);
 }
 
+    static char_u *
+get_signal_name(int sig)
+{
+    int		i;
+    char_u	numbuf[NUMBUFLEN];
+
+    if (sig == SIGKILL)
+	return vim_strsave((char_u *)"kill");
+
+    for (i = 0; signal_info[i].sig != -1; i++)
+	if (sig == signal_info[i].sig)
+	    return strlow_save((char_u *)signal_info[i].name);
+
+    vim_snprintf((char *)numbuf, NUMBUFLEN, "%d", sig);
+    return vim_strsave(numbuf);
+}
+
     char *
 mch_job_status(job_T *job)
 {
@@ -5691,8 +5708,10 @@ mch_job_status(job_T *job)
     if (WIFSIGNALED(status))
     {
 	job->jv_exitval = -1;
-	if (job->jv_status < JOB_ENDED)
-	    ch_log(job->jv_channel, "Job terminated by a signal");
+	job->jv_termsig = get_signal_name(WTERMSIG(status));
+	if (job->jv_status < JOB_ENDED && job->jv_termsig != NULL)
+	    ch_log(job->jv_channel, "Job terminated by signal \"%s\"",
+							      job->jv_termsig);
 	goto return_dead;
     }
     return "run";
@@ -5738,7 +5757,10 @@ mch_detect_ended_job(job_T *job_list)
 		/* LINTED avoid "bitwise operation on signed value" */
 		job->jv_exitval = WEXITSTATUS(status);
 	    else if (WIFSIGNALED(status))
+	    {
 		job->jv_exitval = -1;
+		job->jv_termsig = get_signal_name(WTERMSIG(status));
+	    }
 	    if (job->jv_status < JOB_ENDED)
 	    {
 		ch_log(job->jv_channel, "Job ended");

src/structs.h

@@ -1551,6 +1551,9 @@ struct jobvar_S
     char_u	*jv_tty_out;	/* controlling tty output, allocated */
     jobstatus_T	jv_status;
     char_u	*jv_stoponexit;	/* allocated */
+#ifdef UNIX
+    char_u	*jv_termsig;	/* allocated */
+#endif
     int		jv_exitval;
     char_u	*jv_exit_cb;	/* allocated */
     partial_T	*jv_exit_partial;

src/testdir/test_channel.vim

@@ -2002,3 +2002,27 @@ func Test_raw_large_data()
     unlet g:out
   endtry
 endfunc
+
+func Test_job_exitval_and_termsig()
+  if !has('unix')
+    return
+  endif
+
+  " Terminate job normally
+  let cmd = ['echo']
+  let job = job_start(cmd)
+  call WaitForAssert({-> assert_equal("dead", job_status(job))})
+  let info = job_info(job)
+  call assert_equal(0, info.exitval)
+  call assert_equal("", info.termsig)
+
+  " Terminate job by signal
+  let cmd = ['sleep', '10']
+  let job = job_start(cmd)
+  sleep 10m
+  call job_stop(job)
+  call WaitForAssert({-> assert_equal("dead", job_status(job))})
+  let info = job_info(job)
+  call assert_equal(-1, info.exitval)
+  call assert_equal("term", info.termsig)
+endfunc

src/version.c

@@ -783,6 +783,8 @@ static char *(features[]) =
 
 static int included_patches[] =
 {   /* Add new patch number below this line */
+/**/
+    863,
 /**/
     862,
 /**/