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/*
* Copyright (c) 1995-1998 John Birrell <jb@cimlogic.com.au>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Birrell.
* 4. Neither the name of the author nor the names of any co-contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
/* Allocate space for global thread variables here: */
#define GLOBAL_PTHREAD_PRIVATE
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <paths.h>
#include <poll.h>
#include <unistd.h>
#include <sys/ioctl.h>
#include <sys/sysctl.h>
#include <sys/time.h>
#include <sys/ttycom.h>
#include <sys/param.h>
#include <sys/user.h>
#include <sys/mman.h>
#ifdef _THREAD_SAFE
#include <machine/reg.h>
#include <pthread.h>
#include "pthread_private.h"
#ifdef GCC_2_8_MADE_THREAD_AWARE
typedef void *** (*dynamic_handler_allocator)();
extern void __set_dynamic_handler_allocator(dynamic_handler_allocator);
static pthread_key_t except_head_key;
typedef struct {
void **__dynamic_handler_chain;
void *top_elt[2];
} except_struct;
static void ***dynamic_allocator_handler_fn()
{
except_struct *dh = (except_struct *)pthread_getspecific(except_head_key);
if(dh == NULL) {
dh = (except_struct *)malloc( sizeof(except_struct) );
memset(dh, '\0', sizeof(except_struct));
dh->__dynamic_handler_chain= dh->top_elt;
pthread_setspecific(except_head_key, (void *)dh);
}
return &dh->__dynamic_handler_chain;
}
#endif /* GCC_2_8_MADE_THREAD_AWARE */
/*
* Threaded process initialization
*/
void
_thread_init(void)
{
int fd;
int flags;
int i;
size_t len;
int mib[2];
struct clockinfo clockinfo;
struct sigaction act;
struct sigaltstack alt;
/* Check if this function has already been called: */
if (_thread_initial)
/* Only initialise the threaded application once. */
return;
/*
* Check for the special case of this process running as
* or in place of init as pid = 1:
*/
if (getpid() == 1) {
/*
* Setup a new session for this process which is
* assumed to be running as root.
*/
if (setsid() == -1)
PANIC("Can't set session ID");
if (revoke(_PATH_CONSOLE) != 0)
PANIC("Can't revoke console");
if ((fd = _thread_sys_open(_PATH_CONSOLE, O_RDWR)) < 0)
PANIC("Can't open console");
if (setlogin("root") == -1)
PANIC("Can't set login to root");
if (_thread_sys_ioctl(fd,TIOCSCTTY, (char *) NULL) == -1)
PANIC("Can't set controlling terminal");
if (_thread_sys_dup2(fd,0) == -1 ||
_thread_sys_dup2(fd,1) == -1 ||
_thread_sys_dup2(fd,2) == -1)
PANIC("Can't dup2");
}
/* Get the standard I/O flags before messing with them : */
for (i = 0; i < 3; i++)
if (((_pthread_stdio_flags[i] =
_thread_sys_fcntl(i,F_GETFL, NULL)) == -1) &&
(errno != EBADF))
PANIC("Cannot get stdio flags");
/*
* Create a pipe that is written to by the signal handler to prevent
* signals being missed in calls to _select:
*/
if (_thread_sys_pipe(_thread_kern_pipe) != 0) {
/* Cannot create pipe, so abort: */
PANIC("Cannot create kernel pipe");
}
/* Get the flags for the read pipe: */
else if ((flags = _thread_sys_fcntl(_thread_kern_pipe[0], F_GETFL, NULL)) == -1) {
/* Abort this application: */
PANIC("Cannot get kernel read pipe flags");
}
/* Make the read pipe non-blocking: */
else if (_thread_sys_fcntl(_thread_kern_pipe[0], F_SETFL, flags | O_NONBLOCK) == -1) {
/* Abort this application: */
PANIC("Cannot make kernel read pipe non-blocking");
}
/* Get the flags for the write pipe: */
else if ((flags = _thread_sys_fcntl(_thread_kern_pipe[1], F_GETFL, NULL)) == -1) {
/* Abort this application: */
PANIC("Cannot get kernel write pipe flags");
}
/* Make the write pipe non-blocking: */
else if (_thread_sys_fcntl(_thread_kern_pipe[1], F_SETFL, flags | O_NONBLOCK) == -1) {
/* Abort this application: */
PANIC("Cannot get kernel write pipe flags");
}
/* Allocate and initialize the ready queue: */
else if (_pq_alloc(&_readyq, PTHREAD_MIN_PRIORITY, PTHREAD_LAST_PRIORITY) != 0) {
/* Abort this application: */
PANIC("Cannot allocate priority ready queue.");
}
/* Allocate memory for the thread structure of the initial thread: */
else if ((_thread_initial = (pthread_t) malloc(sizeof(struct pthread))) == NULL) {
/*
* Insufficient memory to initialise this application, so
* abort:
*/
PANIC("Cannot allocate memory for initial thread");
}
/* Allocate memory for the scheduler stack: */
else if ((_thread_kern_sched_stack = malloc(SCHED_STACK_SIZE)) == NULL)
PANIC("Failed to allocate stack for scheduler");
else {
/* Zero the global kernel thread structure: */
memset(&_thread_kern_thread, 0, sizeof(struct pthread));
_thread_kern_thread.flags = PTHREAD_FLAGS_PRIVATE;
memset(_thread_initial, 0, sizeof(struct pthread));
/* Initialize the waiting and work queues: */
TAILQ_INIT(&_waitingq);
TAILQ_INIT(&_workq);
/* Initialize the scheduling switch hook routine: */
_sched_switch_hook = NULL;
/* Give this thread default attributes: */
memcpy((void *) &_thread_initial->attr, &pthread_attr_default,
sizeof(struct pthread_attr));
/* Initialize the thread stack cache: */
SLIST_INIT(&_stackq);
/*
* Create a red zone below the main stack. All other stacks are
* constrained to a maximum size by the paramters passed to
* mmap(), but this stack is only limited by resource limits, so
* this stack needs an explicitly mapped red zone to protect the
* thread stack that is just beyond.
*/
if (mmap((void *) USRSTACK - PTHREAD_STACK_INITIAL -
PTHREAD_STACK_GUARD, PTHREAD_STACK_GUARD, 0, MAP_ANON,
-1, 0) == MAP_FAILED)
PANIC("Cannot allocate red zone for initial thread");
/* Set the main thread stack pointer. */
_thread_initial->stack = (void *) USRSTACK -
PTHREAD_STACK_INITIAL;
/* Set the stack attributes: */
_thread_initial->attr.stackaddr_attr = _thread_initial->stack;
_thread_initial->attr.stacksize_attr = PTHREAD_STACK_INITIAL;
/* Setup the context for the scheduler: */
_setjmp(_thread_kern_sched_jb);
SET_STACK_JB(_thread_kern_sched_jb, _thread_kern_sched_stack +
SCHED_STACK_SIZE - sizeof(double));
SET_RETURN_ADDR_JB(_thread_kern_sched_jb, _thread_kern_scheduler);
/*
* Write a magic value to the thread structure
* to help identify valid ones:
*/
_thread_initial->magic = PTHREAD_MAGIC;
/* Set the initial cancel state */
_thread_initial->cancelflags = PTHREAD_CANCEL_ENABLE |
PTHREAD_CANCEL_DEFERRED;
/* Default the priority of the initial thread: */
_thread_initial->base_priority = PTHREAD_DEFAULT_PRIORITY;
_thread_initial->active_priority = PTHREAD_DEFAULT_PRIORITY;
_thread_initial->inherited_priority = 0;
/* Initialise the state of the initial thread: */
_thread_initial->state = PS_RUNNING;
/* Initialise the queue: */
TAILQ_INIT(&(_thread_initial->join_queue));
/* Initialize the owned mutex queue and count: */
TAILQ_INIT(&(_thread_initial->mutexq));
_thread_initial->priority_mutex_count = 0;
/* Initialize the global scheduling time: */
_sched_ticks = 0;
gettimeofday((struct timeval *) &_sched_tod, NULL);
/* Initialize last active: */
_thread_initial->last_active = (long) _sched_ticks;
/* Initialize the initial context: */
_thread_initial->curframe = NULL;
_thread_initial->ctxtype = CTX_JB_NOSIG;
/* Initialise the rest of the fields: */
_thread_initial->poll_data.nfds = 0;
_thread_initial->poll_data.fds = NULL;
_thread_initial->sig_defer_count = 0;
_thread_initial->yield_on_sig_undefer = 0;
_thread_initial->specific_data = NULL;
_thread_initial->cleanup = NULL;
_thread_initial->flags = 0;
_thread_initial->error = 0;
TAILQ_INIT(&_thread_list);
TAILQ_INSERT_HEAD(&_thread_list, _thread_initial, tle);
_thread_run = _thread_initial;
/* Initialise the global signal action structure: */
sigfillset(&act.sa_mask);
act.sa_handler = (void (*) ()) _thread_sig_handler;
act.sa_flags = SA_SIGINFO | SA_ONSTACK;
/* Clear pending signals for the process: */
sigemptyset(&_process_sigpending);
/* Clear the signal queue: */
memset(_thread_sigq, 0, sizeof(_thread_sigq));
/* Create and install an alternate signal stack: */
alt.ss_sp = malloc(SIGSTKSZ); /* recommended stack size */
alt.ss_size = SIGSTKSZ;
alt.ss_flags = 0;
if (_thread_sys_sigaltstack(&alt, NULL) != 0)
PANIC("Unable to install alternate signal stack");
/* Enter a loop to get the existing signal status: */
for (i = 1; i < NSIG; i++) {
/* Check for signals which cannot be trapped: */
if (i == SIGKILL || i == SIGSTOP) {
}
/* Get the signal handler details: */
else if (_thread_sys_sigaction(i, NULL,
&_thread_sigact[i - 1]) != 0) {
/*
* Abort this process if signal
* initialisation fails:
*/
PANIC("Cannot read signal handler info");
}
/* Initialize the SIG_DFL dummy handler count. */
_thread_dfl_count[i] = 0;
}
/*
* Install the signal handler for the most important
* signals that the user-thread kernel needs. Actually
* SIGINFO isn't really needed, but it is nice to have.
*/
if (_thread_sys_sigaction(_SCHED_SIGNAL, &act, NULL) != 0 ||
_thread_sys_sigaction(SIGINFO, &act, NULL) != 0 ||
_thread_sys_sigaction(SIGCHLD, &act, NULL) != 0) {
/*
* Abort this process if signal initialisation fails:
*/
PANIC("Cannot initialise signal handler");
}
_thread_sigact[_SCHED_SIGNAL - 1].sa_flags = SA_SIGINFO;
_thread_sigact[SIGINFO - 1].sa_flags = SA_SIGINFO;
_thread_sigact[SIGCHLD - 1].sa_flags = SA_SIGINFO;
/* Get the process signal mask: */
_thread_sys_sigprocmask(SIG_SETMASK, NULL, &_process_sigmask);
/* Get the kernel clockrate: */
mib[0] = CTL_KERN;
mib[1] = KERN_CLOCKRATE;
len = sizeof (struct clockinfo);
if (sysctl(mib, 2, &clockinfo, &len, NULL, 0) == 0)
_clock_res_usec = clockinfo.tick;
/* Get the table size: */
if ((_thread_dtablesize = getdtablesize()) < 0) {
/*
* Cannot get the system defined table size, so abort
* this process.
*/
PANIC("Cannot get dtablesize");
}
/* Allocate memory for the file descriptor table: */
if ((_thread_fd_table = (struct fd_table_entry **) malloc(sizeof(struct fd_table_entry *) * _thread_dtablesize)) == NULL) {
/* Avoid accesses to file descriptor table on exit: */
_thread_dtablesize = 0;
/*
* Cannot allocate memory for the file descriptor
* table, so abort this process.
*/
PANIC("Cannot allocate memory for file descriptor table");
}
/* Allocate memory for the pollfd table: */
if ((_thread_pfd_table = (struct pollfd *) malloc(sizeof(struct pollfd) * _thread_dtablesize)) == NULL) {
/*
* Cannot allocate memory for the file descriptor
* table, so abort this process.
*/
PANIC("Cannot allocate memory for pollfd table");
} else {
/*
* Enter a loop to initialise the file descriptor
* table:
*/
for (i = 0; i < _thread_dtablesize; i++) {
/* Initialise the file descriptor table: */
_thread_fd_table[i] = NULL;
}
/* Initialize stdio file descriptor table entries: */
for (i = 0; i < 3; i++) {
if ((_thread_fd_table_init(i) != 0) &&
(errno != EBADF))
PANIC("Cannot initialize stdio file "
"descriptor table entry");
}
}
}
#ifdef GCC_2_8_MADE_THREAD_AWARE
/* Create the thread-specific data for the exception linked list. */
if(pthread_key_create(&except_head_key, NULL) != 0)
PANIC("Failed to create thread specific execption head");
/* Setup the gcc exception handler per thread. */
__set_dynamic_handler_allocator( dynamic_allocator_handler_fn );
#endif /* GCC_2_8_MADE_THREAD_AWARE */
/* Initialise the garbage collector mutex and condition variable. */
if (pthread_mutex_init(&_gc_mutex,NULL) != 0 ||
pthread_cond_init(&_gc_cond,NULL) != 0)
PANIC("Failed to initialise garbage collector mutex or condvar");
}
/*
* Special start up code for NetBSD/Alpha
*/
#if defined(__NetBSD__) && defined(__alpha__)
int
main(int argc, char *argv[], char *env);
int
_thread_main(int argc, char *argv[], char *env)
{
_thread_init();
return (main(argc, argv, env));
}
#endif
#else
/*
* A stub for non-threaded programs.
*/
void
_thread_init(void)
{
}
#endif
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