newlib/winsup/cygserver/process.h

176 lines
3.9 KiB
C++

/* process.h
Copyright 2001, 2002, 2003, 2004, 2005, 2012, 2015 Red Hat Inc.
Written by Robert Collins <rbtcollins@hotmail.com>
This file is part of Cygwin.
This software is a copyrighted work licensed under the terms of the
Cygwin license. Please consult the file "CYGWIN_LICENSE" for
details. */
#ifndef _PROCESS_H
#define _PROCESS_H
#include <assert.h>
#include "threaded_queue.h"
class process_cleanup : public queue_request
{
public:
process_cleanup (class process *const theprocess)
: _process (theprocess)
{
assert (_process);
}
virtual ~process_cleanup ();
virtual void process ();
private:
class process *const _process;
};
class process;
class cleanup_routine
{
friend class process;
public:
cleanup_routine (void *const key)
: _key (key),
_next (NULL)
{}
virtual ~cleanup_routine () = 0;
bool operator== (const cleanup_routine &rhs) const
{
return _key == rhs._key;
}
void *key () const { return _key; }
/* MUST BE SYNCHRONOUS */
virtual void cleanup (class process *) = 0;
private:
void *const _key;
cleanup_routine *_next;
};
class process_cache;
#define hold() _hold(__FILE__,__LINE__)
#define release() _release(__FILE__,__LINE__)
class process
{
friend class process_cache;
friend class process_cleanup;
public:
process (pid_t cygpid, DWORD winpid);
~process ();
pid_t cygpid () const { return _cygpid; }
DWORD winpid () const { return _winpid; }
HANDLE handle () const { return _hProcess; }
bool is_active () const { return _exit_status == STILL_ACTIVE; }
void _hold (const char *file, int line) {
_log (file, line, LOG_DEBUG, "Try hold(%lu)", _cygpid);
EnterCriticalSection (&_access);
_log (file, line, LOG_DEBUG, "holding (%lu)", _cygpid);
}
void _release (const char *file, int line) {
_log (file, line, LOG_DEBUG, "leaving (%lu)", _cygpid);
LeaveCriticalSection (&_access);
}
bool add (cleanup_routine *);
bool remove (const cleanup_routine *);
private:
const pid_t _cygpid;
const DWORD _winpid;
HANDLE _hProcess;
LONG _cleaning_up;
DWORD _exit_status; // Set in the constructor and in exit_code ().
cleanup_routine *_routines_head;
/* used to prevent races-on-delete */
CRITICAL_SECTION _access;
class process *_next;
DWORD check_exit_code ();
void cleanup ();
};
class process_cache
{
// Number of special (i.e., non-process) handles in _wait_array.
// See wait_for_processes () and sync_wait_array () for details.
enum {
SPECIALS_COUNT = 2
};
class submission_loop : public queue_submission_loop
{
public:
submission_loop (process_cache *const cache, threaded_queue *const queue)
: queue_submission_loop (queue, true),
_cache (cache)
{
assert (_cache);
}
private:
process_cache *const _cache;
virtual void request_loop ();
};
friend class submission_loop;
public:
process_cache (const size_t max_procs, const unsigned int initial_workers);
~process_cache ();
class process *process (pid_t cygpid, DWORD winpid);
bool running () const { return _queue.running (); }
bool start () { return _queue.start (); }
bool stop () { return _queue.stop (); }
private:
threaded_queue _queue;
submission_loop _submitter;
size_t _processes_count;
size_t _max_process_count;
class process *_processes_head; // A list sorted by winpid.
// Access to the _wait_array and related fields is not thread-safe,
// since they are used solely by wait_for_processes () and its callees.
HANDLE _wait_array[5 * MAXIMUM_WAIT_OBJECTS];
class process *_process_array[5 * MAXIMUM_WAIT_OBJECTS];
HANDLE _cache_add_trigger; // Actually both add and remove.
CRITICAL_SECTION _cache_write_access; // Actually both read and write access.
void wait_for_processes (HANDLE interrupt);
size_t sync_wait_array (HANDLE interrupt);
void check_and_remove_process (const size_t index);
class process *find (DWORD winpid, class process **previous = NULL);
};
#endif /* _PROCESS_H */