Merge branch 'ab/hooks-regression-fix'

In Git 2.36 we revamped the way how hooks are invoked.  One change
that is end-user visible is that the output of a hook is no longer
directly connected to the standard output of "git" that spawns the
hook, which was noticed post release.  This is getting corrected.

* ab/hooks-regression-fix:
  hook API: fix v2.36.0 regression: hooks should be connected to a TTY
  run-command: add an "ungroup" option to run_process_parallel()

1 files changed, 51 insertions, 19 deletions

diff --git a/run-command.c b/run-command.c
index 789eaa5975..8e36b8ee74 100644
--- a/run-command.c
+++ b/run-command.c
@@ -1472,6 +1472,7 @@ enum child_state {
 	GIT_CP_WAIT_CLEANUP,
 };
 
+int run_processes_parallel_ungroup;
 struct parallel_processes {
 	void *data;
 
@@ -1495,6 +1496,7 @@ struct parallel_processes {
 	struct pollfd *pfd;
 
 	unsigned shutdown : 1;
+	unsigned ungroup : 1;
 
 	int output_owner;
 	struct strbuf buffered_output; /* of finished children */
@@ -1538,7 +1540,7 @@ static void pp_init(struct parallel_processes *pp,
 		    get_next_task_fn get_next_task,
 		    start_failure_fn start_failure,
 		    task_finished_fn task_finished,
-		    void *data)
+		    void *data, int ungroup)
 {
 	int i;
 
@@ -1560,15 +1562,21 @@ static void pp_init(struct parallel_processes *pp,
 	pp->nr_processes = 0;
 	pp->output_owner = 0;
 	pp->shutdown = 0;
+	pp->ungroup = ungroup;
 	CALLOC_ARRAY(pp->children, n);
-	CALLOC_ARRAY(pp->pfd, n);
+	if (pp->ungroup)
+		pp->pfd = NULL;
+	else
+		CALLOC_ARRAY(pp->pfd, n);
 	strbuf_init(&pp->buffered_output, 0);
 
 	for (i = 0; i < n; i++) {
 		strbuf_init(&pp->children[i].err, 0);
 		child_process_init(&pp->children[i].process);
-		pp->pfd[i].events = POLLIN | POLLHUP;
-		pp->pfd[i].fd = -1;
+		if (pp->pfd) {
+			pp->pfd[i].events = POLLIN | POLLHUP;
+			pp->pfd[i].fd = -1;
+		}
 	}
 
 	pp_for_signal = pp;
@@ -1616,24 +1624,31 @@ static int pp_start_one(struct parallel_processes *pp)
 		BUG("bookkeeping is hard");
 
 	code = pp->get_next_task(&pp->children[i].process,
-				 &pp->children[i].err,
+				 pp->ungroup ? NULL : &pp->children[i].err,
 				 pp->data,
 				 &pp->children[i].data);
 	if (!code) {
-		strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
-		strbuf_reset(&pp->children[i].err);
+		if (!pp->ungroup) {
+			strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
+			strbuf_reset(&pp->children[i].err);
+		}
 		return 1;
 	}
-	pp->children[i].process.err = -1;
-	pp->children[i].process.stdout_to_stderr = 1;
+	if (!pp->ungroup) {
+		pp->children[i].process.err = -1;
+		pp->children[i].process.stdout_to_stderr = 1;
+	}
 	pp->children[i].process.no_stdin = 1;
 
 	if (start_command(&pp->children[i].process)) {
-		code = pp->start_failure(&pp->children[i].err,
+		code = pp->start_failure(pp->ungroup ? NULL :
+					 &pp->children[i].err,
 					 pp->data,
 					 pp->children[i].data);
-		strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
-		strbuf_reset(&pp->children[i].err);
+		if (!pp->ungroup) {
+			strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
+			strbuf_reset(&pp->children[i].err);
+		}
 		if (code)
 			pp->shutdown = 1;
 		return code;
@@ -1641,7 +1656,8 @@ static int pp_start_one(struct parallel_processes *pp)
 
 	pp->nr_processes++;
 	pp->children[i].state = GIT_CP_WORKING;
-	pp->pfd[i].fd = pp->children[i].process.err;
+	if (pp->pfd)
+		pp->pfd[i].fd = pp->children[i].process.err;
 	return 0;
 }
 
@@ -1675,6 +1691,7 @@ static void pp_buffer_stderr(struct parallel_processes *pp, int output_timeout)
 static void pp_output(struct parallel_processes *pp)
 {
 	int i = pp->output_owner;
+
 	if (pp->children[i].state == GIT_CP_WORKING &&
 	    pp->children[i].err.len) {
 		strbuf_write(&pp->children[i].err, stderr);
@@ -1697,7 +1714,7 @@ static int pp_collect_finished(struct parallel_processes *pp)
 
 		code = finish_command(&pp->children[i].process);
 
-		code = pp->task_finished(code,
+		code = pp->task_finished(code, pp->ungroup ? NULL :
 					 &pp->children[i].err, pp->data,
 					 pp->children[i].data);
 
@@ -1708,10 +1725,13 @@ static int pp_collect_finished(struct parallel_processes *pp)
 
 		pp->nr_processes--;
 		pp->children[i].state = GIT_CP_FREE;
-		pp->pfd[i].fd = -1;
+		if (pp->pfd)
+			pp->pfd[i].fd = -1;
 		child_process_init(&pp->children[i].process);
 
-		if (i != pp->output_owner) {
+		if (pp->ungroup) {
+			; /* no strbuf_*() work to do here */
+		} else if (i != pp->output_owner) {
 			strbuf_addbuf(&pp->buffered_output, &pp->children[i].err);
 			strbuf_reset(&pp->children[i].err);
 		} else {
@@ -1748,9 +1768,14 @@ int run_processes_parallel(int n,
 	int i, code;
 	int output_timeout = 100;
 	int spawn_cap = 4;
+	int ungroup = run_processes_parallel_ungroup;
 	struct parallel_processes pp;
 
-	pp_init(&pp, n, get_next_task, start_failure, task_finished, pp_cb);
+	/* unset for the next API user */
+	run_processes_parallel_ungroup = 0;
+
+	pp_init(&pp, n, get_next_task, start_failure, task_finished, pp_cb,
+		ungroup);
 	while (1) {
 		for (i = 0;
 		    i < spawn_cap && !pp.shutdown &&
@@ -1767,8 +1792,15 @@ int run_processes_parallel(int n,
 		}
 		if (!pp.nr_processes)
 			break;
-		pp_buffer_stderr(&pp, output_timeout);
-		pp_output(&pp);
+		if (ungroup) {
+			int i;
+
+			for (i = 0; i < pp.max_processes; i++)
+				pp.children[i].state = GIT_CP_WAIT_CLEANUP;
+		} else {
+			pp_buffer_stderr(&pp, output_timeout);
+			pp_output(&pp);
+		}
 		code = pp_collect_finished(&pp);
 		if (code) {
 			pp.shutdown = 1;