diff options
Diffstat (limited to 'winsup/cygwin/sigproc.cc')
| -rw-r--r-- | winsup/cygwin/sigproc.cc | 1295 |
1 files changed, 0 insertions, 1295 deletions
diff --git a/winsup/cygwin/sigproc.cc b/winsup/cygwin/sigproc.cc deleted file mode 100644 index bbbe9831e..000000000 --- a/winsup/cygwin/sigproc.cc +++ /dev/null @@ -1,1295 +0,0 @@ -/* sigproc.cc: inter/intra signal and sub process handler - - Copyright 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, - 2006, 2007, 2008 Red Hat, Inc. - - Written by Christopher Faylor - -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. */ - -#include "winsup.h" -#include "miscfuncs.h" -#include <stdlib.h> -#include <sys/cygwin.h> -#include "cygerrno.h" -#include "pinfo.h" -#include "path.h" -#include "fhandler.h" -#include "dtable.h" -#include "cygheap.h" -#include "child_info_magic.h" -#include "shared_info.h" -#include "cygtls.h" -#include "sigproc.h" -#include "ntdll.h" - -/* - * Convenience defines - */ -#define WSSC 60000 // Wait for signal completion -#define WPSP 40000 // Wait for proc_subproc mutex - -#define no_signals_available(x) (!hwait_sig || hwait_sig == INVALID_HANDLE_VALUE || ((x) && myself->exitcode & EXITCODE_SET) || &_my_tls == _sig_tls) - -#define NPROCS 256 - -/* - * Global variables - */ -struct sigaction *global_sigs; - -const char *__sp_fn ; -int __sp_ln; - -char NO_COPY myself_nowait_dummy[1] = {'0'};// Flag to sig_send that signal goes to - // current process but no wait is required -HANDLE NO_COPY signal_arrived; // Event signaled when a signal has - // resulted in a user-specified - // function call - -#define Static static NO_COPY - -HANDLE NO_COPY sigCONT; // Used to "STOP" a process - -cygthread NO_COPY *hwait_sig; -Static HANDLE wait_sig_inited; // Control synchronization of - // message queue startup -Static bool sigheld; // True if holding signals - -Static int nprocs; // Number of deceased children -Static char cprocs[(NPROCS + 1) * sizeof (pinfo)];// All my children info -#define procs ((pinfo *) cprocs) // All this just to avoid expensive - // constructor operation at DLL startup -Static waitq waitq_head; // Start of queue for wait'ing threads - -Static muto sync_proc_subproc; // Control access to subproc stuff - -_cygtls NO_COPY *_sig_tls; - -Static HANDLE my_sendsig; -Static HANDLE my_readsig; - -/* Function declarations */ -static int __stdcall checkstate (waitq *) __attribute__ ((regparm (1))); -static __inline__ bool get_proc_lock (DWORD, DWORD); -static bool __stdcall remove_proc (int); -static bool __stdcall stopped_or_terminated (waitq *, _pinfo *); -static DWORD WINAPI wait_sig (VOID *arg); - -/* wait_sig bookkeeping */ - -class pending_signals -{ - sigpacket sigs[NSIG + 1]; - sigpacket start; - sigpacket *end; - sigpacket *prev; - sigpacket *curr; -public: - void reset () {curr = &start; prev = &start;} - void add (sigpacket&); - void del (); - sigpacket *next (); - sigpacket *save () const {return curr;} - void restore (sigpacket *saved) {curr = saved;} - friend void __stdcall sig_dispatch_pending (bool); - friend DWORD WINAPI wait_sig (VOID *arg); -}; - -Static pending_signals sigq; - -/* Functions */ -void __stdcall -sigalloc () -{ - cygheap->sigs = global_sigs = - (struct sigaction *) ccalloc_abort (HEAP_SIGS, NSIG, sizeof (struct sigaction)); - global_sigs[SIGSTOP].sa_flags = SA_RESTART | SA_NODEFER; -} - -void __stdcall -signal_fixup_after_exec () -{ - global_sigs = cygheap->sigs; - /* Set up child's signal handlers */ - for (int i = 0; i < NSIG; i++) - { - global_sigs[i].sa_mask = 0; - if (global_sigs[i].sa_handler != SIG_IGN) - { - global_sigs[i].sa_handler = SIG_DFL; - global_sigs[i].sa_flags &= ~ SA_SIGINFO; - } - } -} - -void __stdcall -wait_for_sigthread () -{ - sigproc_printf ("wait_sig_inited %p", wait_sig_inited); - HANDLE hsig_inited = wait_sig_inited; - WaitForSingleObject (hsig_inited, INFINITE); - wait_sig_inited = NULL; - myself->sendsig = my_sendsig; - myself->process_state |= PID_ACTIVE; - myself->process_state &= ~PID_INITIALIZING; - ForceCloseHandle1 (hsig_inited, wait_sig_inited); - sigproc_printf ("process/signal handling enabled, state %p", myself->process_state); -} - -/* Get the sync_proc_subproc muto to control access to - * children, proc arrays. - * Attempt to handle case where process is exiting as we try to grab - * the mutex. - */ -static bool -get_proc_lock (DWORD what, DWORD val) -{ - Static int lastwhat = -1; - if (!sync_proc_subproc) - { - sigproc_printf ("sync_proc_subproc is NULL (1)"); - return false; - } - if (sync_proc_subproc.acquire (WPSP)) - { - lastwhat = what; - return true; - } - if (!sync_proc_subproc) - { - sigproc_printf ("sync_proc_subproc is NULL (2)"); - return false; - } - system_printf ("Couldn't aquire sync_proc_subproc for(%d,%d), last %d, %E", - what, val, lastwhat); - return true; -} - -static bool __stdcall -proc_can_be_signalled (_pinfo *p) -{ - if (!(p->exitcode & EXITCODE_SET)) - { - if (ISSTATE (p, PID_INITIALIZING) || - (((p)->process_state & (PID_ACTIVE | PID_IN_USE)) == - (PID_ACTIVE | PID_IN_USE))) - return true; - } - - set_errno (ESRCH); - return false; -} - -bool __stdcall -pid_exists (pid_t pid) -{ - return pinfo (pid)->exists (); -} - -/* Return true if this is one of our children, false otherwise. */ -static inline bool __stdcall -mychild (int pid) -{ - for (int i = 0; i < nprocs; i++) - if (procs[i]->pid == pid) - return true; - return false; -} - -/* Handle all subprocess requests - */ -int __stdcall -proc_subproc (DWORD what, DWORD val) -{ - int rc = 1; - int potential_match; - _pinfo *child; - int clearing; - waitq *w; - -#define wval ((waitq *) val) -#define vchild (*((pinfo *) val)) - - sigproc_printf ("args: %x, %d", what, val); - - if (!get_proc_lock (what, val)) // Serialize access to this function - { - system_printf ("couldn't get proc lock. what %d, val %d", what, val); - goto out1; - } - - switch (what) - { - /* Add a new subprocess to the children arrays. - * (usually called from the main thread) - */ - case PROC_ADDCHILD: - /* Filled up process table? */ - if (nprocs >= NPROCS) - { - sigproc_printf ("proc table overflow: hit %d processes, pid %d\n", - nprocs, vchild->pid); - rc = 0; - set_errno (EAGAIN); - break; - } - /* fall through intentionally */ - - case PROC_DETACHED_CHILD: - if (vchild != myself) - { - vchild->ppid = what == PROC_DETACHED_CHILD ? 1 : myself->pid; - vchild->uid = myself->uid; - vchild->gid = myself->gid; - vchild->pgid = myself->pgid; - vchild->sid = myself->sid; - vchild->ctty = myself->ctty; - vchild->cygstarted = true; - vchild->process_state |= PID_INITIALIZING | (myself->process_state & PID_USETTY); - } - if (what == PROC_DETACHED_CHILD) - break; - procs[nprocs] = vchild; - rc = procs[nprocs].wait (); - if (rc) - { - sigproc_printf ("added pid %d to proc table, slot %d", vchild->pid, - nprocs); - nprocs++; - } - break; - - /* Handle a wait4() operation. Allocates an event for the calling - * thread which is signaled when the appropriate pid exits or stops. - * (usually called from the main thread) - */ - case PROC_WAIT: - wval->ev = NULL; // Don't know event flag yet - - if (wval->pid == -1 || !wval->pid) - child = NULL; // Not looking for a specific pid - else if (!mychild (wval->pid)) - goto out; // invalid pid. flag no such child - - wval->status = 0; // Don't know status yet - sigproc_printf ("wval->pid %d, wval->options %d", wval->pid, wval->options); - - /* If the first time for this thread, create a new event, otherwise - * reset the event. - */ - if ((wval->ev = wval->thread_ev) == NULL) - { - wval->ev = wval->thread_ev = CreateEvent (&sec_none_nih, TRUE, FALSE, - NULL); - ProtectHandle1 (wval->ev, wq_ev); - } - - ResetEvent (wval->ev); - w = waitq_head.next; - waitq_head.next = wval; /* Add at the beginning. */ - wval->next = w; /* Link in rest of the list. */ - clearing = 0; - goto scan_wait; - - /* Clear all waiting threads. Called from exceptions.cc prior to - the main thread's dispatch to a signal handler function. - (called from wait_sig thread) */ - case PROC_CLEARWAIT: - /* Clear all "wait"ing threads. */ - if (val) - sigproc_printf ("clear waiting threads"); - else - sigproc_printf ("looking for processes to reap, nprocs %d", nprocs); - clearing = val; - - scan_wait: - /* Scan the linked list of wait()ing threads. If a wait's parameters - match this pid, then activate it. */ - for (w = &waitq_head; w->next != NULL; w = w->next) - { - if ((potential_match = checkstate (w)) > 0) - sigproc_printf ("released waiting thread"); - else if (!clearing && !(w->next->options & WNOHANG) && potential_match < 0) - sigproc_printf ("only found non-terminated children"); - else if (potential_match <= 0) // nothing matched - { - sigproc_printf ("waiting thread found no children"); - HANDLE oldw = w->next->ev; - w->next->pid = 0; - if (clearing) - w->next->status = -1; /* flag that a signal was received */ - else if (!potential_match || !(w->next->options & WNOHANG)) - w->next->ev = NULL; - if (!SetEvent (oldw)) - system_printf ("couldn't wake up wait event %p, %E", oldw); - w->next = w->next->next; - } - if (w->next == NULL) - break; - } - - if (!clearing) - sigproc_printf ("finished processing terminated/stopped child"); - else - { - waitq_head.next = NULL; - sigproc_printf ("finished clearing"); - } - - if (global_sigs[SIGCHLD].sa_handler == (void *) SIG_IGN) - for (int i = 0; i < nprocs; i += remove_proc (i)) - continue; - } - -out: - sync_proc_subproc.release (); // Release the lock -out1: - sigproc_printf ("returning %d", rc); - return rc; -#undef wval -#undef vchild -} - -// FIXME: This is inelegant -void -_cygtls::remove_wq (DWORD wait) -{ - if (exit_state < ES_FINAL && sync_proc_subproc - && sync_proc_subproc.acquire (wait)) - { - for (waitq *w = &waitq_head; w->next != NULL; w = w->next) - if (w->next == &wq) - { - ForceCloseHandle1 (wq.thread_ev, wq_ev); - w->next = wq.next; - break; - } - sync_proc_subproc.release (); - } -} - -/* Terminate the wait_subproc thread. - Called on process exit. - Also called by spawn_guts to disassociate any subprocesses from this - process. Subprocesses will then know to clean up after themselves and - will not become procs. */ -void __stdcall -proc_terminate () -{ - sigproc_printf ("nprocs %d", nprocs); - if (nprocs) - { - sync_proc_subproc.acquire (WPSP); - - proc_subproc (PROC_CLEARWAIT, 1); - - /* Clean out proc processes from the pid list. */ - int i; - for (i = 0; i < nprocs; i++) - { - procs[i]->ppid = 1; - if (procs[i].wait_thread) - { - // CloseHandle (procs[i].rd_proc_pipe); - procs[i].wait_thread->terminate_thread (); - } - procs[i].release (); - } - nprocs = 0; - sync_proc_subproc.release (); - } - sigproc_printf ("leaving"); -} - -/* Clear pending signal */ -void __stdcall -sig_clear (int target_sig) -{ - if (&_my_tls != _sig_tls) - sig_send (myself, -target_sig); - else - { - sigpacket *q; - sigpacket *save = sigq.save (); - sigq.reset (); - while ((q = sigq.next ())) - if (q->si.si_signo == target_sig) - { - q->si.si_signo = __SIGDELETE; - break; - } - sigq.restore (save); - } -} - -extern "C" int -sigpending (sigset_t *mask) -{ - sigset_t outset = (sigset_t) sig_send (myself, __SIGPENDING); - if (outset == SIG_BAD_MASK) - return -1; - *mask = outset; - return 0; -} - -/* Force the wait_sig thread to wake up and scan for pending signals */ -void __stdcall -sig_dispatch_pending (bool fast) -{ - if (exit_state || &_my_tls == _sig_tls) - { -#ifdef DEBUGGING - sigproc_printf ("exit_state %d, cur thread id %p, _sig_tls %p, sigq.start.next %p", - exit_state, GetCurrentThreadId (), _sig_tls, sigq.start.next); -#endif - return; - } - -#ifdef DEBUGGING - sigproc_printf ("flushing"); -#endif - sig_send (myself, fast ? __SIGFLUSHFAST : __SIGFLUSH); -} - -void __stdcall -create_signal_arrived () -{ - if (signal_arrived) - return; - /* local event signaled when main thread has been dispatched - to a signal handler function. */ - signal_arrived = CreateEvent (&sec_none_nih, TRUE, FALSE, NULL); - ProtectHandle (signal_arrived); -} - -/* Signal thread initialization. Called from dll_crt0_1. - - This routine starts the signal handling thread. The wait_sig_inited - event is used to signal that the thread is ready to handle signals. - We don't wait for this during initialization but instead detect it - in sig_send to gain a little concurrency. */ -void __stdcall -sigproc_init () -{ - wait_sig_inited = CreateEvent (&sec_none_nih, TRUE, FALSE, NULL); - ProtectHandle (wait_sig_inited); - - /* sync_proc_subproc is used by proc_subproc. It serialises - access to the children and proc arrays. */ - sync_proc_subproc.init ("sync_proc_subproc"); - - hwait_sig = new cygthread (wait_sig, 0, cygself, "sig"); - hwait_sig->zap_h (); -} - -/* Called on process termination to terminate signal and process threads. - */ -void __stdcall -sigproc_terminate (exit_states es) -{ - exit_states prior_exit_state = exit_state; - exit_state = es; - if (prior_exit_state >= ES_FINAL) - sigproc_printf ("already performed"); - else - { - sigproc_printf ("entering"); - sig_send (myself_nowait, __SIGEXIT); - proc_terminate (); // clean up process stuff - } -} - -int __stdcall -sig_send (_pinfo *p, int sig) -{ - if (sig == __SIGHOLD) - sigheld = true; - else if (!sigheld) - /* nothing */; - else if (sig == __SIGFLUSH || sig == __SIGFLUSHFAST) - return 0; - else if (sig == __SIGNOHOLD || sig == __SIGEXIT) - { - SetEvent (sigCONT); - sigheld = false; - } - else if (&_my_tls == _main_tls) - { -#ifdef DEBUGGING - system_printf ("signal %d sent to %p while signals are on hold", sig, p); -#endif - return -1; - } - siginfo_t si = {0}; - si.si_signo = sig; - si.si_code = SI_KERNEL; - si.si_pid = si.si_uid = si.si_errno = 0; - return sig_send (p, si); -} - -/* Send a signal to another process by raising its signal semaphore. - If pinfo *p == NULL, send to the current process. - If sending to this process, wait for notification that a signal has - completed before returning. */ -int __stdcall -sig_send (_pinfo *p, siginfo_t& si, _cygtls *tls) -{ - int rc = 1; - bool its_me; - HANDLE sendsig; - sigpacket pack; - bool communing = si.si_signo == __SIGCOMMUNE; - - pack.wakeup = NULL; - bool wait_for_completion; - if (!(its_me = (!hExeced && (p == NULL || p == myself || p == myself_nowait)))) - { - /* It is possible that the process is not yet ready to receive messages - * or that it has exited. Detect this. - */ - if (!proc_can_be_signalled (p)) /* Is the process accepting messages? */ - { - sigproc_printf ("invalid pid %d(%x), signal %d", - p->pid, p->process_state, si.si_signo); - goto out; - } - wait_for_completion = false; - } - else - { - if (no_signals_available (si.si_signo != __SIGEXIT)) - { - sigproc_printf ("my_sendsig %p, myself->sendsig %p, exit_state %d", - my_sendsig, myself->sendsig, exit_state); - set_errno (EAGAIN); - goto out; // Either exiting or not yet initializing - } - if (wait_sig_inited) - wait_for_sigthread (); - wait_for_completion = p != myself_nowait && _my_tls.isinitialized () && !exit_state; - p = myself; - } - - - if (its_me) - sendsig = my_sendsig; - else - { - HANDLE dupsig; - DWORD dwProcessId; - for (int i = 0; !p->sendsig && i < 10000; i++) - low_priority_sleep (0); - if (p->sendsig) - { - dupsig = p->sendsig; - dwProcessId = p->dwProcessId; - } - else - { - dupsig = p->exec_sendsig; - dwProcessId = p->exec_dwProcessId; - } - if (!dupsig) - { - set_errno (EAGAIN); - sigproc_printf ("sendsig handle never materialized"); - goto out; - } - HANDLE hp = OpenProcess (PROCESS_DUP_HANDLE, false, dwProcessId); - if (!hp) - { - __seterrno (); - sigproc_printf ("OpenProcess failed, %E"); - goto out; - } - VerifyHandle (hp); - if (!DuplicateHandle (hp, dupsig, hMainProc, &sendsig, false, 0, - DUPLICATE_SAME_ACCESS) || !sendsig) - { - __seterrno (); - sigproc_printf ("DuplicateHandle failed, %E"); - CloseHandle (hp); - goto out; - } - VerifyHandle (sendsig); - if (!communing) - CloseHandle (hp); - else - { - si._si_commune._si_process_handle = hp; - - HANDLE& tome = si._si_commune._si_write_handle; - HANDLE& fromthem = si._si_commune._si_read_handle; - if (!CreatePipe (&fromthem, &tome, &sec_all_nih, 0)) - { - sigproc_printf ("CreatePipe for __SIGCOMMUNE failed, %E"); - __seterrno (); - goto out; - } - if (!DuplicateHandle (hMainProc, tome, hp, &tome, false, 0, - DUPLICATE_SAME_ACCESS | DUPLICATE_CLOSE_SOURCE)) - { - sigproc_printf ("DuplicateHandle for __SIGCOMMUNE failed, %E"); - __seterrno (); - goto out; - } - } - } - - sigproc_printf ("sendsig %p, pid %d, signal %d, its_me %d", sendsig, p->pid, si.si_signo, its_me); - - sigset_t pending; - if (!its_me) - pack.mask = NULL; - else if (si.si_signo == __SIGPENDING) - pack.mask = &pending; - else if (si.si_signo == __SIGFLUSH || si.si_signo > 0) - pack.mask = tls ? &tls->sigmask : &_main_tls->sigmask; - else - pack.mask = NULL; - - pack.si = si; - if (!pack.si.si_pid) - pack.si.si_pid = myself->pid; - if (!pack.si.si_uid) - pack.si.si_uid = myself->uid; - pack.pid = myself->pid; - pack.tls = tls; - if (wait_for_completion) - { - pack.wakeup = CreateEvent (&sec_none_nih, FALSE, FALSE, NULL); - sigproc_printf ("wakeup %p", pack.wakeup); - ProtectHandle (pack.wakeup); - } - - char *leader; - size_t packsize; - if (!communing || !(si._si_commune._si_code & PICOM_EXTRASTR)) - { - leader = (char *) &pack; - packsize = sizeof (pack); - } - else - { - size_t n = strlen (si._si_commune._si_str); - char *p = leader = (char *) alloca (sizeof (pack) + sizeof (n) + n); - memcpy (p, &pack, sizeof (pack)); p += sizeof (pack); - memcpy (p, &n, sizeof (n)); p += sizeof (n); - memcpy (p, si._si_commune._si_str, n); p += n; - packsize = p - leader; - } - - DWORD nb; - if (!WriteFile (sendsig, leader, packsize, &nb, NULL) || nb != packsize) - { - /* Couldn't send to the pipe. This probably means that the - process is exiting. */ - if (!its_me) - { - __seterrno (); - sigproc_printf ("WriteFile for pipe %p failed, %E", sendsig); - ForceCloseHandle (sendsig); - } - else - { - if (no_signals_available (true)) - sigproc_printf ("I'm going away now"); - else if (!p->exec_sendsig) - system_printf ("error sending signal %d to pid %d, pipe handle %p, %E", - si.si_signo, p->pid, sendsig); - set_errno (EACCES); - } - goto out; - } - - - /* No need to wait for signal completion unless this was a signal to - this process. - - If it was a signal to this process, wait for a dispatched signal. - Otherwise just wait for the wait_sig to signal that it has finished - processing the signal. */ - if (wait_for_completion) - { - sigproc_printf ("Waiting for pack.wakeup %p", pack.wakeup); - rc = WaitForSingleObject (pack.wakeup, WSSC); - ForceCloseHandle (pack.wakeup); - } - else - { - rc = WAIT_OBJECT_0; - sigproc_printf ("Not waiting for sigcomplete. its_me %d signal %d", - its_me, si.si_signo); - if (!its_me) - ForceCloseHandle (sendsig); - } - - pack.wakeup = NULL; - if (rc == WAIT_OBJECT_0) - rc = 0; // Successful exit - else - { - if (!no_signals_available (true)) - system_printf ("wait for sig_complete event failed, signal %d, rc %d, %E", - si.si_signo, rc); - set_errno (ENOSYS); - rc = -1; - } - - if (wait_for_completion && si.si_signo != __SIGFLUSHFAST) - _my_tls.call_signal_handler (); - goto out; - -out: - if (communing && rc) - { - if (si._si_commune._si_process_handle) - CloseHandle (si._si_commune._si_process_handle); - if (si._si_commune._si_read_handle) - CloseHandle (si._si_commune._si_read_handle); - } - if (pack.wakeup) - ForceCloseHandle (pack.wakeup); - if (si.si_signo != __SIGPENDING) - /* nothing */; - else if (!rc) - rc = (int) pending; - else - rc = SIG_BAD_MASK; - sigproc_printf ("returning %p from sending signal %d", rc, si.si_signo); - return rc; -} - -int child_info::retry_count = 10; -/* Initialize some of the memory block passed to child processes - by fork/spawn/exec. */ - -child_info::child_info (unsigned in_cb, child_info_types chtype, bool need_subproc_ready) -{ - memset (this, 0, in_cb); - cb = in_cb; - - /* It appears that when running under WOW64 on Vista 64, the first DWORD - value in the datastructure lpReserved2 is pointing to (msv_count in - Cygwin), has to reflect the size of that datastructure as used in the - Microsoft C runtime (a count value, counting the number of elements in - two subsequent arrays, BYTE[count and HANDLE[count]), even though the C - runtime isn't used. Otherwise, if msv_count is 0 or too small, the - datastructure gets overwritten. - - This seems to be a bug in Vista's WOW64, which apparently copies the - lpReserved2 datastructure not using the cbReserved2 size information, - but using the information given in the first DWORD within lpReserved2 - instead. 32 bit Windows and former WOW64 don't care if msv_count is 0 - or a sensible non-0 count value. However, it's not clear if a non-0 - count doesn't result in trying to evaluate the content, so we do this - really only for Vista 64 for now. - - Note: It turns out that a non-zero value *does* harm operation on - XP 64 and 2K3 64 (Crash in CreateProcess call). - - The value is sizeof (child_info_*) / 5 which results in a count which - covers the full datastructure, plus not more than 4 extra bytes. This - is ok as long as the child_info structure is cosily stored within a bigger - datastructure. */ - msv_count = wincap.needs_count_in_si_lpres2 () ? in_cb / 5 : 0; - - intro = PROC_MAGIC_GENERIC; - magic = CHILD_INFO_MAGIC; - type = chtype; - fhandler_union_cb = sizeof (fhandler_union); - user_h = cygwin_user_h; - if (strace.attached ()) - flag |= _CI_STRACED; - if (need_subproc_ready) - { - subproc_ready = CreateEvent (&sec_all, FALSE, FALSE, NULL); - flag |= _CI_ISCYGWIN; - } - sigproc_printf ("subproc_ready %p", subproc_ready); - cygheap = ::cygheap; - cygheap_max = ::cygheap_max; - retry = child_info::retry_count; - /* Create an inheritable handle to pass to the child process. This will - allow the child to duplicate handles from the parent to itself. */ - parent = NULL; - if (!DuplicateHandle (hMainProc, hMainProc, hMainProc, &parent, 0, TRUE, - DUPLICATE_SAME_ACCESS)) - system_printf ("couldn't create handle to myself for child, %E"); -} - -child_info::~child_info () -{ - if (subproc_ready) - CloseHandle (subproc_ready); - if (parent) - CloseHandle (parent); -} - -child_info_fork::child_info_fork () : - child_info (sizeof *this, _PROC_FORK, true) -{ -} - -child_info_spawn::child_info_spawn (child_info_types chtype, bool need_subproc_ready) : - child_info (sizeof *this, chtype, need_subproc_ready) -{ -} - -void -child_info::ready (bool execed) -{ - if (!subproc_ready) - { - sigproc_printf ("subproc_ready not set"); - return; - } - - if (dynamically_loaded) - sigproc_printf ("not really ready"); - else if (!SetEvent (subproc_ready)) - api_fatal ("SetEvent failed"); - else - sigproc_printf ("signalled %p that I was ready", subproc_ready); - - if (execed) - { - CloseHandle (subproc_ready); - subproc_ready = NULL; - } -} - -bool -child_info::sync (pid_t pid, HANDLE& hProcess, DWORD howlong) -{ - bool res; - HANDLE w4[2]; - unsigned n = 0; - unsigned nsubproc_ready; - - if (!subproc_ready) - nsubproc_ready = WAIT_OBJECT_0 + 3; - else - { - w4[n++] = subproc_ready; - nsubproc_ready = 0; - } - w4[n++] = hProcess; - - sigproc_printf ("n %d, waiting for subproc_ready(%p) and child process(%p)", n, w4[0], w4[1]); - DWORD x = WaitForMultipleObjects (n, w4, FALSE, howlong); - x -= WAIT_OBJECT_0; - if (x >= n) - { - system_printf ("wait failed, pid %u, %E", pid); - res = false; - } - else - { - if (x != nsubproc_ready) - { - res = false; - GetExitCodeProcess (hProcess, &exit_code); - } - else - { - res = true; - exit_code = STILL_ACTIVE; - if (type == _PROC_EXEC && myself->wr_proc_pipe) - { - ForceCloseHandle1 (hProcess, childhProc); - hProcess = NULL; - } - } - sigproc_printf ("pid %u, WFMO returned %d, res %d", pid, x, res); - } - return res; -} - -DWORD -child_info::proc_retry (HANDLE h) -{ - if (!exit_code) - return EXITCODE_OK; - switch (exit_code) - { - case STILL_ACTIVE: /* shouldn't happen */ - sigproc_printf ("STILL_ACTIVE? How'd we get here?"); - break; - case STATUS_DLL_NOT_FOUND: - return exit_code; - case STATUS_CONTROL_C_EXIT: - if (saw_ctrl_c ()) - return EXITCODE_OK; - /* fall through intentionally */ - case STATUS_DLL_INIT_FAILED: - case STATUS_DLL_INIT_FAILED_LOGOFF: - case EXITCODE_RETRY: - if (retry-- > 0) - exit_code = 0; - break; - /* Count down non-recognized exit codes more quickly since they aren't - due to known conditions. */ - default: - if (!iscygwin () && (exit_code & 0xffff0000) != 0xc0000000) - break; - if ((retry -= 2) < 0) - retry = 0; - else - exit_code = 0; - } - if (!exit_code) - ForceCloseHandle1 (h, childhProc); - return exit_code; -} - -bool -child_info_fork::handle_failure (DWORD err) -{ - if (retry > 0) - ExitProcess (EXITCODE_RETRY); - return 0; -} - -/* Check the state of all of our children to see if any are stopped or - * terminated. - */ -static int __stdcall -checkstate (waitq *parent_w) -{ - int potential_match = 0; - - sigproc_printf ("nprocs %d", nprocs); - - /* Check already dead processes first to see if they match the criteria - * given in w->next. */ - int res; - for (int i = 0; i < nprocs; i++) - if ((res = stopped_or_terminated (parent_w, procs[i]))) - { - remove_proc (i); - potential_match = 1; - goto out; - } - - sigproc_printf ("no matching terminated children found"); - potential_match = -!!nprocs; - -out: - sigproc_printf ("returning %d", potential_match); - return potential_match; -} - -/* Remove a proc from procs by swapping it with the last child in the list. - Also releases shared memory of exited processes. */ -static bool __stdcall -remove_proc (int ci) -{ - if (procs[ci]->exists ()) - return true; - - sigproc_printf ("removing procs[%d], pid %d, nprocs %d", ci, procs[ci]->pid, - nprocs); - if (procs[ci] != myself) - { - procs[ci].release (); - if (procs[ci].hProcess) - ForceCloseHandle1 (procs[ci].hProcess, childhProc); - } - if (ci < --nprocs) - { - /* Wait for proc_waiter thread to make a copy of this element before - moving it or it may become confused. The chances are very high that - the proc_waiter thread has already done this by the time we - get here. */ - while (!procs[nprocs].waiter_ready) - low_priority_sleep (0); - procs[ci] = procs[nprocs]; - } - return 0; -} - -/* Check status of child process vs. waitq member. - - parent_w is the pointer to the parent of the waitq member in question. - child is the subprocess being considered. - - Returns non-zero if waiting thread released. */ -static bool __stdcall -stopped_or_terminated (waitq *parent_w, _pinfo *child) -{ - int might_match; - waitq *w = parent_w->next; - - sigproc_printf ("considering pid %d", child->pid); - if (w->pid == -1) - might_match = 1; - else if (w->pid == 0) - might_match = child->pgid == myself->pgid; - else if (w->pid < 0) - might_match = child->pgid == -w->pid; - else - might_match = (w->pid == child->pid); - - if (!might_match) - return false; - - int terminated; - - if (!((terminated = (child->process_state == PID_EXITED)) - || ((w->options & WCONTINUED) && child->stopsig == SIGCONT) - || ((w->options & WUNTRACED) && child->stopsig && child->stopsig != SIGCONT))) - return false; - - parent_w->next = w->next; /* successful wait. remove from wait queue */ - w->pid = child->pid; - - if (!terminated) - { - sigproc_printf ("stopped child, stopsig %d", child->stopsig); - if (child->stopsig == SIGCONT) - w->status = __W_CONTINUED; - else - w->status = (child->stopsig << 8) | 0x7f; - child->stopsig = 0; - } - else - { - w->status = (__uint16_t) child->exitcode; - - add_rusage (&myself->rusage_children, &child->rusage_children); - add_rusage (&myself->rusage_children, &child->rusage_self); - - if (w->rusage) - { - add_rusage ((struct rusage *) w->rusage, &child->rusage_children); - add_rusage ((struct rusage *) w->rusage, &child->rusage_self); - } - } - - if (!SetEvent (w->ev)) /* wake up wait4 () immediately */ - system_printf ("couldn't wake up wait event %p, %E", w->ev); - return true; -} - -static void -talktome (siginfo_t *si) -{ - unsigned size = sizeof (*si); - sigproc_printf ("pid %d wants some information", si->si_pid); - if (si->_si_commune._si_code & PICOM_EXTRASTR) - { - size_t n; - DWORD nb; - if (!ReadFile (my_readsig, &n, sizeof (n), &nb, NULL) || nb != sizeof (n)) - return; - siginfo_t *newsi = (siginfo_t *) alloca (size += n + 1); - *newsi = *si; - newsi->_si_commune._si_str = (char *) (newsi + 1); - if (!ReadFile (my_readsig, newsi->_si_commune._si_str, n, &nb, NULL) || nb != n) - return; - newsi->_si_commune._si_str[n] = '\0'; - si = newsi; - } - - pinfo pi (si->si_pid); - if (pi) - new cygthread (commune_process, size, si, "commune_process"); -} - -void -pending_signals::add (sigpacket& pack) -{ - sigpacket *se; - if (sigs[pack.si.si_signo].si.si_signo) - return; - se = sigs + pack.si.si_signo; - *se = pack; - se->mask = &pack.tls->sigmask; - se->next = NULL; - if (end) - end->next = se; - end = se; - if (!start.next) - start.next = se; -} - -void -pending_signals::del () -{ - sigpacket *next = curr->next; - prev->next = next; - curr->si.si_signo = 0; -#ifdef DEBUGGING - curr->next = NULL; -#endif - if (end == curr) - end = prev; - curr = next; -} - -sigpacket * -pending_signals::next () -{ - sigpacket *res; - prev = curr; - if (!curr || !(curr = curr->next)) - res = NULL; - else - res = curr; - return res; -} - -/* Called separately to allow stack space reutilization by wait_sig. - This function relies on the fact that it will be called after cygheap - has been set up. For the case of non-dynamic DLL initialization this - means that it relies on the implicit serialization guarantted by being - run as part of DLL_PROCESS_ATTACH. */ -static void __attribute__ ((noinline)) -init_sig_pipe() -{ - char char_sa_buf[1024]; - PSECURITY_ATTRIBUTES sa_buf = sec_user_nih ((PSECURITY_ATTRIBUTES) char_sa_buf, cygheap->user.sid()); - if (!CreatePipe (&my_readsig, &my_sendsig, sa_buf, 0)) - api_fatal ("couldn't create signal pipe, %E"); - ProtectHandle (my_readsig); -} - - -/* Process signals by waiting for signal data to arrive in a pipe. - Set a completion event if one was specified. */ -static DWORD WINAPI -wait_sig (VOID *) -{ - init_sig_pipe (); - /* Initialization */ - SetThreadPriority (GetCurrentThread (), WAIT_SIG_PRIORITY); - - sigCONT = CreateEvent (&sec_none_nih, FALSE, FALSE, NULL); - - SetEvent (wait_sig_inited); - - _sig_tls = &_my_tls; - sigproc_printf ("entering ReadFile loop, my_readsig %p, my_sendsig %p", - my_readsig, my_sendsig); - - sigpacket pack; - pack.si.si_signo = 0; - for (;;) - { - if (pack.si.si_signo == __SIGHOLD) - WaitForSingleObject (sigCONT, INFINITE); - DWORD nb; - pack.tls = NULL; - if (!ReadFile (my_readsig, &pack, sizeof (pack), &nb, NULL)) - break; - - if (nb != sizeof (pack)) - { - system_printf ("short read from signal pipe: %d != %d", nb, - sizeof (pack)); - continue; - } - - if (!pack.si.si_signo) - { -#ifdef DEBUGGING - system_printf ("zero signal?"); -#endif - continue; - } - - sigset_t dummy_mask; - if (!pack.mask) - { - dummy_mask = _main_tls->sigmask; - pack.mask = &dummy_mask; - } - - sigpacket *q; - bool clearwait = false; - switch (pack.si.si_signo) - { - case __SIGCOMMUNE: - talktome (&pack.si); - break; - case __SIGSTRACE: - strace.hello (); - break; - case __SIGPENDING: - *pack.mask = 0; - unsigned bit; - sigq.reset (); - while ((q = sigq.next ())) - if (pack.tls->sigmask & (bit = SIGTOMASK (q->si.si_signo))) - *pack.mask |= bit; - break; - case __SIGHOLD: - goto loop; - break; - case __SIGNOHOLD: - case __SIGFLUSH: - case __SIGFLUSHFAST: - sigq.reset (); - while ((q = sigq.next ())) - { - int sig = q->si.si_signo; - if (sig == __SIGDELETE || q->process () > 0) - sigq.del (); - if (sig == __SIGNOHOLD && q->si.si_signo == SIGCHLD) - clearwait = true; - } - break; - case __SIGEXIT: - hwait_sig = (cygthread *) INVALID_HANDLE_VALUE; - sigproc_printf ("saw __SIGEXIT"); - break; /* handle below */ - default: - if (pack.si.si_signo < 0) - sig_clear (-pack.si.si_signo); - else - { - int sig = pack.si.si_signo; - // FIXME: REALLY not right when taking threads into consideration. - // We need a per-thread queue since each thread can have its own - // list of blocked signals. CGF 2005-08-24 - if (sigq.sigs[sig].si.si_signo && sigq.sigs[sig].tls == pack.tls) - sigproc_printf ("sig %d already queued", pack.si.si_signo); - else - { - int sigres = pack.process (); - if (sigres <= 0) - { -#ifdef DEBUGGING2 - if (!sigres) - system_printf ("Failed to arm signal %d from pid %d", pack.sig, pack.pid); -#endif - sigq.add (pack); // FIXME: Shouldn't add this in !sh condition - } - } - if (sig == SIGCHLD) - clearwait = true; - } - break; - } - if (clearwait) - proc_subproc (PROC_CLEARWAIT, 0); - loop: - if (pack.wakeup) - { - sigproc_printf ("signalling pack.wakeup %p", pack.wakeup); - SetEvent (pack.wakeup); - } - if (pack.si.si_signo == __SIGEXIT) - break; - } - - ForceCloseHandle (my_readsig); - sigproc_printf ("signal thread exiting"); - ExitThread (0); -} |