diff options
Diffstat (limited to 'job.c')
| -rw-r--r-- | job.c | 109 |
1 files changed, 61 insertions, 48 deletions
@@ -145,6 +145,17 @@ extern int wait (); #endif /* Don't have `union wait'. */ +/* How to set close-on-exec for a file descriptor. */ + +#if !defined F_SETFD +# define CLOSE_ON_EXEC(_d) +#else +# ifndef FD_CLOEXEC +# define FD_CLOEXEC 1 +# endif +# define CLOSE_ON_EXEC(_d) (void) fcntl ((_d), F_SETFD, FD_CLOEXEC) +#endif + #ifdef VMS static int vms_jobsefnmask = 0; #endif /* !VMS */ @@ -218,9 +229,6 @@ int w32_kill(int pid, int sig) #endif /* WINDOWS32 */ -#ifndef MAKE_JOBSERVER -# define free_job_token(c) -#else static void free_job_token (child) struct child *child; @@ -248,7 +256,6 @@ free_job_token (child) child->job_token = '-'; } -#endif /* Write an error message describing the exit status given in @@ -302,14 +309,13 @@ vmsWaitForChildren(int *status) /* Handle a dead child. This handler may or may not ever be installed. If we're using the jobserver blocking read, we need it. First, installing - it ensures the read will interrupt on SIGCHLD. Second, we close the dup'd - read side of the pipe to ensure we don't enter another blocking read - without reaping all the dead children. In this case we don't need the - dead_children count. + it ensures the read will interrupt on SIGCHLD. Second, we reset the + blocking bit on the read side of the pipe to ensure we don't enter another + blocking read without reaping all the dead children. In this case we + don't need the dead_children count. If we don't have either waitpid or wait3, then make is unreliable, but we - use the dead_children count to reap children as best we can. In this case - job_rfd will never be >= 0. */ + use the dead_children count to reap children as best we can. */ static unsigned int dead_children = 0; @@ -319,9 +325,15 @@ child_handler (sig) { ++dead_children; - if (job_rfd >= 0) - close (job_rfd); - job_rfd = -1; +#ifdef HAVE_JOBSERVER + if (job_fds[0] >= 0) + { + int fl = fcntl(job_fds[0], F_GETFL, 0); + + if (fl >= 0) + fcntl(job_fds[0], F_SETFL, fl | O_NONBLOCK); + } +#endif if (debug_flag) printf (_("Got a SIGCHLD; %u unreaped children.\n"), dead_children); @@ -330,11 +342,12 @@ child_handler (sig) extern int shell_function_pid, shell_function_completed; -/* Reap dead children, storing the returned status and the new command +/* Reap all dead children, storing the returned status and the new command state (`cs_finished') in the `file' member of the `struct child' for the - dead child, and removing the child from the chain. If BLOCK nonzero, - reap at least one child, waiting for it to die if necessary. If ERR is - nonzero, print an error message first. */ + dead child, and removing the child from the chain. In addition, if BLOCK + nonzero, we block in this function until we've reaped at least one + complete child, waiting for it to die if necessary. If ERR is nonzero, + print an error message first. */ void reap_children (block, err) @@ -415,19 +428,18 @@ reap_children (block, err) { /* A remote status command failed miserably. Punt. */ remote_status_lose: -#ifdef EINTR - if (errno == EINTR) + if (EINTR_SET) continue; -#endif + pfatal_with_name ("remote_status"); } else { /* No remote children. Check for local children. */ - #if !defined(__MSDOS__) && !defined(_AMIGA) && !defined(WINDOWS32) if (any_local) { + local_wait: #ifdef VMS vmsWaitForChildren (&status); pid = c->pid; @@ -446,15 +458,14 @@ reap_children (block, err) if (pid < 0) { /* The wait*() failed miserably. Punt. */ -#ifdef EINTR - if (errno == EINTR) - continue; -#endif + if (EINTR_SET) + goto local_wait; + pfatal_with_name ("wait"); } else if (pid > 0) { - /* We got one; chop the status word up. */ + /* We got a child exit; chop the status word up. */ exit_code = WEXITSTATUS (status); exit_sig = WIFSIGNALED (status) ? WTERMSIG (status) : 0; coredump = WCOREDUMP (status); @@ -1171,20 +1182,16 @@ start_waiting_job (c) c->remote = start_remote_job_p (1); - /* If not, start it locally. */ - if (!c->remote) + /* If we are running at least one job already and the load average + is too high, make this one wait. */ + if (!c->remote && job_slots_used > 0 && load_too_high ()) { - /* If we are running at least one job already and the load average - is too high, make this one wait. */ - if (job_slots_used > 0 && load_too_high ()) - { - /* Put this child on the chain of children waiting - for the load average to go down. */ - set_command_state (f, cs_running); - c->next = waiting_jobs; - waiting_jobs = c; - return 0; - } + /* Put this child on the chain of children waiting for the load average + to go down. */ + set_command_state (f, cs_running); + c->next = waiting_jobs; + waiting_jobs = c; + return 0; } /* Start the first command; reap_children will run later command lines. */ @@ -1379,19 +1386,25 @@ new_job (file) } /* 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 with EBADF. */ - else if (read (job_rfd, &c->job_token, 1) < 1) + before we got here we'll return immediately with EAGAIN because + the signal handler unsets the blocking bit. */ + else if (read (job_fds[0], &c->job_token, 1) < 1) { - if (errno == EINTR) - ; + int fl; - /* If EBADF, we got a SIGCHLD before. Otherwise, who knows? */ - else if (errno != EBADF) +#if !defined(EAGAIN) +# define EAGAIN EWOULDBLOCK +#endif + if (errno != EINTR && errno != EAGAIN) pfatal_with_name (_("read jobs pipe")); - /* Something's done; reap it. We don't force a block here; if - something strange happened and nothing's ready, just come back - and wait some more. */ + /* Set the blocking bit on the read FD again, just in case. */ + fl = fcntl(job_fds[0], F_GETFL, 0); + if (fl >= 0) + fcntl(job_fds[0], F_SETFL, fl & ~O_NONBLOCK); + + /* Something's done. We don't want to block for a whole child, + just reap whatever's there. */ reap_children (0, 0); } |