From fac6d9a6d59a83e96314103b3181f6f692537014 Mon Sep 17 00:00:00 2001 From: "Michael I. Bushnell" Date: Thu, 25 Apr 1996 19:36:50 +0000 Subject: Many changes to support multi-threading. See ChangeLog. --- proc/wait.c | 127 ++++++++++++++++++++---------------------------------------- 1 file changed, 43 insertions(+), 84 deletions(-) (limited to 'proc/wait.c') diff --git a/proc/wait.c b/proc/wait.c index 57fc4cad..6c862887 100644 --- a/proc/wait.c +++ b/proc/wait.c @@ -30,9 +30,6 @@ #include #include "process_S.h" -#include "process_reply_U.h" -#include "ourmsg_U.h" - #include /* Return nonzero if a `waitpid' on WAIT_PID by a process @@ -47,14 +44,11 @@ waiter_cares (pid_t wait_pid, pid_t mypgrp, (wait_pid == WAIT_MYPGRP && pgrp == mypgrp)); } -/* A process is dying. Send SIGCHLD to the parent. Check if the parent is - waiting for us to exit; if so wake it up, otherwise, enter us as a - zombie. */ +/* A process is dying. Send SIGCHLD to the parent. Wake the parent +if it is waiting for us to exit. */ void alert_parent (struct proc *p) { - struct zombie *z; - send_signal (p->p_parent->p_msgport, SIGCHLD, p->p_parent->p_task); if (!p->p_exiting) @@ -65,50 +59,8 @@ alert_parent (struct proc *p) condition_broadcast (&p->p_parent->p_wakeup); p->p_parent->p_waiting = 0; } - - z = malloc (sizeof (struct zombie)); - - z->pid = p->p_pid; - z->pgrp = p->p_pgrp->pg_pgid; - z->parent = p->p_parent; - z->exit_status = p->p_status; - bzero (&z->ru, sizeof (struct rusage)); - z->next = zombie_list; - zombie_list = z; -} - -/* Process P is exiting. Find all the zombies who claim P as their parent - and make them claim startup_proc as their parent; then wake it - up if appropriate. */ -void -reparent_zombies (struct proc *p) -{ - struct zombie *z, *prevz; - struct wait_c *w = &startup_proc->p_continuation.wait_c; - int initsignalled = 0; - - for (z = zombie_list, prevz = 0; z; prevz = z, z = z->next) - { - if (z->parent != p) - continue; - z->parent = startup_proc; - - if (!initsignalled) - { - send_signal (startup_proc->p_msgport, SIGCHLD, startup_proc->p_task); - initsignalled = 1; - } - - if (startup_proc->p_waiting) - { - condition_broadcast (&startup_proc->p_wakeup); - startup_proc->p_waiting = 0; - } - } } - -/* Implement proc_wait as described in . */ kern_return_t S_proc_wait (struct proc *p, mach_port_t reply_port, @@ -119,24 +71,25 @@ S_proc_wait (struct proc *p, struct rusage *ru, pid_t *pid_status) { - struct wait_c *w; - struct zombie *z, *prevz; + int cancel; - start_over: - for (z = zombie_list, prevz = 0; z; prevz = z, z = z->next) + int child_ready (struct proc *child) { - if (z->parent == p && waiter_cares (pid, p->p_pgrp->pg_pgid, - z->pid, z->pgrp)) - { - *status = z->exit_status; - bzero (ru, sizeof (struct rusage)); - *pid_status = z->pid; - (prevz ? prevz->next : zombie_list) = z->next; - free (z); - return 0; - } + if (child->p_waited) + return 0; + if (child->p_dead) + return 1; + if (!child->p_stopped) + return 0; + if (child->p_traced || (options & WUNTRACED)) + return 1; + return 0; } + if (!p) + return EOPNOTSUPP; + + start_over: /* See if we can satisfy the request with a stopped child; also check for invalid arguments here. */ if (!p->p_ochild) @@ -144,14 +97,15 @@ S_proc_wait (struct proc *p, if (pid > 0) { - struct proc *child = pid_find (pid); + struct proc *child = pid_find_allow_zombie (pid); if (!child || child->p_parent != p) return ECHILD; - if (child->p_stopped && !child->p_waited - && ((options & WUNTRACED) || child->p_traced)) + if (child_ready (child)) { child->p_waited = 1; *status = child->p_status; + if (child->p_dead) + complete_exit (child); bzero (ru, sizeof (struct rusage)); *pid_status = pid; return 0; @@ -161,19 +115,20 @@ S_proc_wait (struct proc *p, { struct proc *child; int had_a_match = pid == 0; - + for (child = p->p_ochild; child; child = child->p_sib) if (waiter_cares (pid, p->p_pgrp->pg_pgid, child->p_pid, child->p_pgrp->pg_pgid)) { had_a_match = 1; - if (child->p_stopped && !child->p_waited - && ((options & WUNTRACED) || child->p_traced)) + if (child_ready (child)) { child->p_waited = 1; *status = child->p_status; - bzero (ru, sizeof (struct rusage)); *pid_status = child->p_pid; + if (child->p_dead) + complete_exit (child); + bzero (ru, sizeof (struct rusage)); return 0; } } @@ -186,7 +141,11 @@ S_proc_wait (struct proc *p, return EWOULDBLOCK; p->p_waiting = 1; - condition_wait (&p->p_wakeup, &global_lock); + cancel = hurd_condition_wait (&p->p_wakeup, &global_lock); + if (p->p_dead) + return EOPNOTSUPP; + if (cancel) + return EINTR; goto start_over; } @@ -195,6 +154,9 @@ kern_return_t S_proc_mark_stop (struct proc *p, int signo) { + if (!p) + return EOPNOTSUPP; + p->p_stopped = 1; p->p_status = W_STOPCODE (signo); p->p_waited = 0; @@ -216,6 +178,9 @@ kern_return_t S_proc_mark_exit (struct proc *p, int status) { + if (!p) + return EOPNOTSUPP; + if (WIFSTOPPED (status)) return EINVAL; @@ -228,6 +193,8 @@ S_proc_mark_exit (struct proc *p, kern_return_t S_proc_mark_cont (struct proc *p) { + if (!p) + return EOPNOTSUPP; p->p_stopped = 0; return 0; } @@ -236,6 +203,8 @@ S_proc_mark_cont (struct proc *p) kern_return_t S_proc_mark_traced (struct proc *p) { + if (!p) + return EOPNOTSUPP; p->p_traced = 1; return 0; } @@ -245,20 +214,10 @@ kern_return_t S_proc_mod_stopchild (struct proc *p, int value) { + if (!p) + return EOPNOTSUPP; /* VALUE is nonzero if we should send SIGCHLD. */ p->p_nostopcld = ! value; return 0; } -/* Return 1 if pid is in use by a zombie. */ -int -zombie_check_pid (pid_t pid) -{ - struct zombie *z; - for (z = zombie_list; z; z = z->next) - if (z->pid == pid || -z->pid == pid - || z->pgrp == pid || -z->pgrp == pid) - return 1; - return 0; -} - -- cgit v1.2.3