newlib/winsup/cygwin/dtable.h
Christopher Faylor ca35d41cec Implement fhandler reference counting.
* cygheap.h
(cygheap_fdmanip::release): Make virtual.
(cygheap_fdnew::~cygheap_fdnew): New destructor increments reference count when
fd has been allocated.
(cygheap_fdget::fh): New (old?) field.
(cygheap_fdget::cygheap_fdget): Increment reference count when we've found an
active fd.  Set fh appropriately.
(cygheap_fdget::~cygheap_fdget): Decrement reference count when appropriate.
Delete fh if reference count goes to zero.
(cygheap_fdget::release): New function.  Do more bookkeping on release.
* dtable.cc (dtable::release): Change from void to boolean return.  Only delete
the fhandler when its reference count is <= 0 (this should be a fairly unusual
case).  Return true if fhandler has been deleted.
(cygwin_attach_handle_to_fd): Increment reference count when fh is assigned.
(dtable::init_std_file_from_handle): Ditto.
* dtable.h (dtable::release): Change return to boolean.
* fhandler.cc (fhandler_base::fhandler_base): Set new isclosed flag to false.
Set _refcnt to zero.
(fhandler_base::close): Simplify paranoid debugging output.  Set new isclosed()
flag.
(fhandler_base_overlapped::wait_overlapped): Use isclosed() flag to avoid
querying the exception handle.
* fhandler.h (fhandler_base::_refcnt): New field.
(fhandler_base::refcnt): New function.
(fhandler_base::isclosed): Implement.
(fhandler_base::fhandler_base): Set isclosed to false.
* syscalls.cc: Remove space after function before parentheses for several
strace printfs.
(dup): Add standard strace "leaver" code.
(dup2): Ditto.
(dup3): Ditto.
(remove): Ditto.
(getpid): Ditto.
(getppid): Ditto.
(lseek64): Fix strace debugging to correctly use %R.
* fhandler_termios.cc (fhandler_termios::tcsetpgrp): Avoid sending signals to
other processes if we're debugging since it can cause a deadlock with the
calling debugger.
* exceptions.cc (_cygtls::call_signal_handler): Add debugging-only strace
output.
2011-12-17 00:03:31 +00:00

106 lines
3.2 KiB
C++

/* dtable.h: fd table definition.
Copyright 2000, 2001, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
2010, 2011 Red Hat, Inc.
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. */
/* Initial and increment values for cygwin's fd table */
#define NOFILE_INCR 32
/* Maximum size we allow expanding to. */
#define OPEN_MAX_MAX (100 * NOFILE_INCR)
#include "thread.h"
#include "sync.h"
class suffix_info;
#define BFH_OPTS (PC_NULLEMPTY | PC_FULL | PC_POSIX)
class dtable
{
fhandler_base **fds;
#ifdef NEWVFORK
fhandler_base **fds_on_hold;
#endif
fhandler_base **archetypes;
unsigned narchetypes;
unsigned farchetype;
static const int initial_archetype_size = 8;
int first_fd_for_open;
int cnt_need_fixup_before;
void lock () {lock_process::locker.acquire ();}
void unlock () {lock_process::locker.release ();}
public:
size_t size;
dtable () : archetypes (NULL), narchetypes (0), farchetype (0), first_fd_for_open(3), cnt_need_fixup_before(0) {}
void init () {first_fd_for_open = 3;}
void dec_need_fixup_before ()
{ if (cnt_need_fixup_before > 0) --cnt_need_fixup_before; }
void inc_need_fixup_before ()
{ cnt_need_fixup_before++; }
bool need_fixup_before ()
{ return cnt_need_fixup_before > 0; }
void move_fd (int, int);
int vfork_child_dup ();
void vfork_parent_restore ();
void vfork_child_fixup ();
fhandler_base *dup_worker (fhandler_base *oldfh, int flags);
int extend (int howmuch);
void fixup_after_fork (HANDLE);
inline int not_open (int fd)
{
lock ();
int res = fd < 0 || fd >= (int) size || fds[fd] == NULL;
unlock ();
return res;
}
int find_unused_handle (int start);
int find_unused_handle () { return find_unused_handle (first_fd_for_open);}
bool release (int fd) __attribute__ ((regparm (2)));
void init_std_file_from_handle (int fd, HANDLE handle);
int dup3 (int oldfd, int newfd, int flags);
void fixup_after_exec ();
inline fhandler_base *&operator [](int fd) const { return fds[fd]; }
bool select_read (int fd, select_stuff *);
bool select_write (int fd, select_stuff *);
bool select_except (int fd, select_stuff *);
operator fhandler_base **() {return fds;}
void stdio_init ();
void get_debugger_info ();
void set_file_pointers_for_exec ();
#ifdef NEWVFORK
bool in_vfork_cleanup () {return fds_on_hold == fds;}
#endif
fhandler_base *find_archetype (device& dev);
fhandler_base **add_archetype ();
void delete_archetype (fhandler_base *);
void fixup_before_exec (DWORD win_proc_id);
void fixup_before_fork (DWORD win_proc_id);
friend void dtable_init ();
friend void __stdcall close_all_files (bool);
friend class fhandler_disk_file;
friend class cygheap_fdmanip;
friend class cygheap_fdget;
friend class cygheap_fdnew;
friend class cygheap_fdenum;
friend class lock_process;
};
fhandler_base *build_fh_dev (const device&, const char * = NULL);
fhandler_base *build_fh_name (const char *, unsigned = 0, suffix_info * = NULL);
fhandler_base *build_fh_pc (path_conv& pc);
void dtable_init ();
void stdio_init ();
extern dtable fdtab;
extern "C" int getfdtabsize ();
extern "C" void setfdtabsize (int);