summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorRoland McGrath <roland@redhat.com>1992-05-09 02:26:35 +0000
committerRoland McGrath <roland@redhat.com>1992-05-09 02:26:35 +0000
commitd9dedc8f27fef12a82e9b411a245e73f25ffb26f (patch)
treed051121cb478edc8c93df8a6428ad7598818d571
parent569cdeac4ec5760944de2dc95a883d8dfe1d2612 (diff)
downloadgunmake-d9dedc8f27fef12a82e9b411a245e73f25ffb26f.tar.gz
Formerly job.c.~65~
-rw-r--r--job.c60
1 files changed, 51 insertions, 9 deletions
diff --git a/job.c b/job.c
index 5c64fb8..44361c8 100644
--- a/job.c
+++ b/job.c
@@ -176,7 +176,7 @@ child_error (target_name, exit_code, exit_sig, coredump, ignored)
}
}
-int child_died = 0;
+static unsigned int dead_children = 0;
/* Notice that a child died.
reap_children should be called when convenient. */
@@ -184,7 +184,11 @@ int
child_handler (sig)
int sig;
{
- child_died = 1;
+ ++dead_children;
+
+ if (debug_flag)
+ printf ("Got a SIGCHLD; %d unreaped children.\n", dead_children);
+
return 0;
}
@@ -203,7 +207,7 @@ reap_children (block, err)
WAIT_T status;
while ((children != 0 || shell_function_pid != 0) &&
- (block || child_died))
+ (block || dead_children > 0))
{
int remote = 0;
register int pid;
@@ -211,14 +215,33 @@ reap_children (block, err)
register struct child *lastc, *c;
int child_failed;
- if (err && !child_died)
+ if (err && dead_children == 0)
{
/* We might block for a while, so let the user know why. */
fflush (stdout);
error ("*** Waiting for unfinished jobs....");
}
- child_died = 0;
+ /* We have one less dead child to reap.
+ The test and decrement are not atomic; if it is compiled into:
+ register = dead_children - 1;
+ dead_children = register;
+ a SIGCHLD could come between the two instructions.
+ child_handler increments dead_children.
+ The second instruction here would lose that increment. But the
+ only effect of dead_children being wrong is that we might wait
+ longer than necessary to reap a child, and lose some parallelism;
+ and we might print the "Waiting for unfinished jobs" message above
+ when not necessary. */
+
+ if (dead_children != 0)
+ --dead_children;
+
+ if (debug_flag)
+ for (c = children; c != 0; c = c->next)
+ printf ("Live child 0x%08lx PID %d%s\n",
+ (unsigned long int) c,
+ c->pid, c->remote ? " (remote)" : "");
/* First, check for remote children. */
pid = remote_status (&exit_code, &exit_sig, &coredump, 0);
@@ -232,9 +255,10 @@ reap_children (block, err)
else
#endif
pid = wait (&status);
- fprintf (stderr,"%sblocking wait returned %d\n", block?"":"non",pid);
- if (pid <= 0)
+ if (pid < 0)
+ pfatal_with_name ("wait");
+ else if (pid == 0)
/* No local children. */
break;
else
@@ -281,6 +305,12 @@ reap_children (block, err)
}
else
{
+ if (debug_flag)
+ printf ("Reaping %s child 0x%08lx PID %d%s\n",
+ child_failed ? "losing" : "winning",
+ (unsigned long int) c,
+ c->pid, c->remote ? " (remote)" : "");
+
/* If this child had the good stdin, say it is now free. */
if (c->good_stdin)
good_stdin_used = 0;
@@ -307,6 +337,8 @@ reap_children (block, err)
if (!err)
/* If there are more commands to run, try to start them. */
start_job (c);
+ else
+ c->file->command_state = cs_finished;
switch (c->file->command_state)
{
@@ -334,6 +366,11 @@ reap_children (block, err)
/* Notice if the target of the commands has been changed. */
notice_finished_file (c->file);
+ if (debug_flag)
+ printf ("Removing child 0x%08lx PID %d%s from chain.\n",
+ (unsigned long int) c,
+ c->pid, c->remote ? " (remote)" : "");
+
/* Remove the child from the chain and free it. */
if (lastc == 0)
children = c->next;
@@ -344,8 +381,9 @@ reap_children (block, err)
/* There is now another slot open. */
--job_slots_used;
- /* If the job failed, and the -k flag was not given, die. */
- if (child_failed && !keep_going_flag)
+ /* If the job failed, and the -k flag was not given, die,
+ unless we are already in the process of dying. */
+ if (!err && child_failed && !keep_going_flag)
die (1);
}
@@ -645,6 +683,10 @@ new_job (file)
{
case cs_running:
c->next = children;
+ if (debug_flag)
+ printf ("Putting child 0x%08lx PID %d%s on the chain.\n",
+ (unsigned long int) c,
+ c->pid, c->remote ? " (remote)" : "");
children = c;
/* One more job slot is in use. */
++job_slots_used;