summaryrefslogtreecommitdiff
path: root/job.c
diff options
context:
space:
mode:
Diffstat (limited to 'job.c')
-rw-r--r--job.c72
1 files changed, 36 insertions, 36 deletions
diff --git a/job.c b/job.c
index 34d1ddd..01a99ae 100644
--- a/job.c
+++ b/job.c
@@ -310,8 +310,6 @@ extern int shell_function_pid, shell_function_completed;
complete child, waiting for it to die if necessary. If ERR is nonzero,
print an error message first. */
-static int rc_block, rc_reap_all, rc_got_block, rc_start_rfd, rc_end_rfd;
-
void
reap_children (block, err)
int block, err;
@@ -326,11 +324,6 @@ reap_children (block, err)
# define REAP_MORE dead_children
#endif
- rc_block = block;
- rc_reap_all = 0;
- rc_got_block = 0;
- rc_start_rfd = job_rfd;
-
/* As long as:
We have at least one child outstanding OR a shell function in progress,
@@ -451,7 +444,6 @@ reap_children (block, err)
{
/* No local children are dead. */
reap_more = 0;
- rc_reap_all = 1;
if (!block || !any_remote)
break;
@@ -677,10 +669,8 @@ reap_children (block, err)
/* Only block for one child. */
block = 0;
- rc_block = block;
}
- rc_end_rfd = job_rfd;
return;
}
@@ -691,11 +681,12 @@ free_child (child)
register struct child *child;
{
/* If this child is the only one it was our "free" job, so don't put a
- token back for it. */
+ token back for it. This child has already been removed from the list,
+ so if there any left this wasn't the last one. */
- if (job_fds[1] >= 0 && (child != children || child->next != 0))
+ if (job_fds[1] >= 0 && children)
{
- char *token = '+';
+ char token = '+';
/* Write a job token back to the pipe. */
@@ -874,7 +865,7 @@ start_job_command (child)
? "%s" : (char *) 0, p);
/* Optimize an empty command. People use this for timestamp rules,
- and forking a useless shell all the time leads to inefficiency. */
+ so avoid forking a useless shell. */
#if !defined(VMS) && !defined(_AMIGA)
if (
@@ -1361,6 +1352,7 @@ new_job (file)
/* Wait for a job slot to be freed up. If we allow an infinite number
don't bother; also job_slots will == 0 if we're using the jobserver. */
+
if (job_slots != 0)
while (job_slots_used == job_slots)
reap_children (1, 0);
@@ -1369,41 +1361,49 @@ new_job (file)
/* If we are controlling multiple jobs make sure we have a token before
starting the child. */
+ /* This can be inefficient. There's a decent chance that this job won't
+ actually have to run any subprocesses: the command script may be empty
+ or otherwise optimized away. It would be nice if we could defer
+ obtaining a token until just before we need it, in start_job_command.
+ To do that we'd need to keep track of whether we'd already obtained a
+ token (since start_job_command is called for each line of the job, not
+ just once). Also more thought needs to go into the entire algorithm;
+ this is where the old parallel job code waits, so... */
+
else if (job_fds[0] >= 0)
- if (children == 0)
- {
- char token = '-';
+ while (1)
+ {
+ char token;
- while (token == '-')
/* If we don't already have a job started, use our "free" token. */
- if (children == 0)
- token = '+';
+ if (!children)
+ break;
/* Read a token. As long as there's no token available we'll block.
If we get a SIGCHLD we'll return with EINTR. If one happened
before we got here we'll return immediately with EBADF because
the signal handler closes the dup'd file descriptor. */
- else if (read (job_rfd, &c->job_token, 1) < 1)
+ if (read (job_rfd, &token, 1) == 1)
{
- if (errno != EINTR && errno != EBADF)
- pfatal_with_name (_("read jobs pipe"));
+ if (debug_flag)
+ printf (_("Obtained token for child 0x%08lx (%s).\n"),
+ (unsigned long int) c, c->file->name);
+ break;
+ }
- /* Re-dup the read side of the pipe, so the signal handler can
- notify us if we miss a child. */
- if (job_rfd < 0)
- job_rfd = dup (job_fds[0]);
+ if (errno != EINTR && errno != EBADF)
+ pfatal_with_name (_("read jobs pipe"));
- /* Something's done. We don't want to block for a whole child,
- just reap whatever's there. */
- reap_children (0, 0);
- }
+ /* Re-dup the read side of the pipe, so the signal handler can
+ notify us if we miss a child. */
+ if (job_rfd < 0)
+ job_rfd = dup (job_fds[0]);
- assert (c->job_token != '-');
- if (debug_flag)
- printf (_("Obtained token for child 0x%08lx (%s).\n"),
- (unsigned long int) c, c->file->name);
- }
+ /* Something's done. We don't want to block for a whole child,
+ just reap whatever's there. */
+ reap_children (0, 0);
+ }
#endif
/* The job is now primed. Start it running.