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-rw-r--r--tevent/tevent_signal.c291
1 files changed, 0 insertions, 291 deletions
diff --git a/tevent/tevent_signal.c b/tevent/tevent_signal.c
deleted file mode 100644
index 36907af6b..000000000
--- a/tevent/tevent_signal.c
+++ /dev/null
@@ -1,291 +0,0 @@
-/*
- Unix SMB/CIFS implementation.
-
- common events code for signal events
-
- Copyright (C) Andrew Tridgell 2007
-
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 3 of the License, or
- (at your option) any later version.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <http://www.gnu.org/licenses/>.
-*/
-
-#include <signal.h>
-#include "replace.h"
-#include "system/filesys.h"
-#include "system/select.h"
-#include "tevent.h"
-#include "tevent_internal.h"
-#include "tevent_util.h"
-
-#define NUM_SIGNALS 64
-
-/* maximum number of SA_SIGINFO signals to hold in the queue */
-#define SA_INFO_QUEUE_COUNT 10
-
-struct sigcounter {
- uint32_t count;
- uint32_t seen;
-};
-
-#define SIG_INCREMENT(s) (s).count++
-#define SIG_SEEN(s, n) (s).seen += (n)
-#define SIG_PENDING(s) ((s).seen != (s).count)
-
-
-/*
- the poor design of signals means that this table must be static global
-*/
-static struct sig_state {
- struct signal_event *sig_handlers[NUM_SIGNALS+1];
- struct sigaction *oldact[NUM_SIGNALS+1];
- struct sigcounter signal_count[NUM_SIGNALS+1];
- struct sigcounter got_signal;
- int pipe_hack[2];
-#ifdef SA_SIGINFO
- /* with SA_SIGINFO we get quite a lot of info per signal */
- siginfo_t *sig_info[NUM_SIGNALS+1];
- struct sigcounter sig_blocked[NUM_SIGNALS+1];
-#endif
-} *sig_state;
-
-/*
- return number of sigcounter events not processed yet
-*/
-static uint32_t sig_count(struct sigcounter s)
-{
- if (s.count >= s.seen) {
- return s.count - s.seen;
- }
- return 1 + (0xFFFFFFFF & ~(s.seen - s.count));
-}
-
-/*
- signal handler - redirects to registered signals
-*/
-static void signal_handler(int signum)
-{
- char c = 0;
- SIG_INCREMENT(sig_state->signal_count[signum]);
- SIG_INCREMENT(sig_state->got_signal);
- /* doesn't matter if this pipe overflows */
- write(sig_state->pipe_hack[1], &c, 1);
-}
-
-#ifdef SA_SIGINFO
-/*
- signal handler with SA_SIGINFO - redirects to registered signals
-*/
-static void signal_handler_info(int signum, siginfo_t *info, void *uctx)
-{
- uint32_t count = sig_count(sig_state->signal_count[signum]);
- sig_state->sig_info[signum][count] = *info;
-
- signal_handler(signum);
-
- /* handle SA_SIGINFO */
- if (count+1 == SA_INFO_QUEUE_COUNT) {
- /* we've filled the info array - block this signal until
- these ones are delivered */
- sigset_t set;
- sigemptyset(&set);
- sigaddset(&set, signum);
- sigprocmask(SIG_BLOCK, &set, NULL);
- SIG_INCREMENT(sig_state->sig_blocked[signum]);
- }
-}
-#endif
-
-/*
- destroy a signal event
-*/
-static int signal_event_destructor(struct signal_event *se)
-{
- se->event_ctx->num_signal_handlers--;
- DLIST_REMOVE(sig_state->sig_handlers[se->signum], se);
- if (sig_state->sig_handlers[se->signum] == NULL) {
- /* restore old handler, if any */
- sigaction(se->signum, sig_state->oldact[se->signum], NULL);
- sig_state->oldact[se->signum] = NULL;
-#ifdef SA_SIGINFO
- if (se->sa_flags & SA_SIGINFO) {
- talloc_free(sig_state->sig_info[se->signum]);
- sig_state->sig_info[se->signum] = NULL;
- }
-#endif
- }
- return 0;
-}
-
-/*
- this is part of the pipe hack needed to avoid the signal race condition
-*/
-static void signal_pipe_handler(struct event_context *ev, struct fd_event *fde,
- uint16_t flags, void *private)
-{
- char c[16];
- /* its non-blocking, doesn't matter if we read too much */
- read(sig_state->pipe_hack[0], c, sizeof(c));
-}
-
-/*
- add a signal event
- return NULL on failure (memory allocation error)
-*/
-struct signal_event *common_event_add_signal(struct event_context *ev,
- TALLOC_CTX *mem_ctx,
- int signum,
- int sa_flags,
- event_signal_handler_t handler,
- void *private_data)
-{
- struct signal_event *se;
-
- if (signum >= NUM_SIGNALS) {
- return NULL;
- }
-
- /* the sig_state needs to be on a global context as it can last across
- multiple event contexts */
- if (sig_state == NULL) {
- sig_state = talloc_zero(talloc_autofree_context(), struct sig_state);
- if (sig_state == NULL) {
- return NULL;
- }
- }
-
- se = talloc(mem_ctx?mem_ctx:ev, struct signal_event);
- if (se == NULL) return NULL;
-
- se->event_ctx = ev;
- se->handler = handler;
- se->private_data = private_data;
- se->signum = signum;
- se->sa_flags = sa_flags;
-
- /* Ensure, no matter the destruction order, that we always have a handle on the global sig_state */
- if (!talloc_reference(se, sig_state)) {
- return NULL;
- }
-
- /* only install a signal handler if not already installed */
- if (sig_state->sig_handlers[signum] == NULL) {
- struct sigaction act;
- ZERO_STRUCT(act);
- act.sa_handler = signal_handler;
- act.sa_flags = sa_flags;
-#ifdef SA_SIGINFO
- if (sa_flags & SA_SIGINFO) {
- act.sa_handler = NULL;
- act.sa_sigaction = signal_handler_info;
- if (sig_state->sig_info[signum] == NULL) {
- sig_state->sig_info[signum] = talloc_array(sig_state, siginfo_t, SA_INFO_QUEUE_COUNT);
- if (sig_state->sig_info[signum] == NULL) {
- talloc_free(se);
- return NULL;
- }
- }
- }
-#endif
- sig_state->oldact[signum] = talloc(sig_state, struct sigaction);
- if (sig_state->oldact[signum] == NULL) {
- talloc_free(se);
- return NULL;
- }
- if (sigaction(signum, &act, sig_state->oldact[signum]) == -1) {
- talloc_free(se);
- return NULL;
- }
- }
-
- DLIST_ADD(sig_state->sig_handlers[signum], se);
-
- talloc_set_destructor(se, signal_event_destructor);
-
- /* we need to setup the pipe hack handler if not already
- setup */
- if (ev->pipe_fde == NULL) {
- if (sig_state->pipe_hack[0] == 0 &&
- sig_state->pipe_hack[1] == 0) {
- pipe(sig_state->pipe_hack);
- ev_set_blocking(sig_state->pipe_hack[0], false);
- ev_set_blocking(sig_state->pipe_hack[1], false);
- }
- ev->pipe_fde = event_add_fd(ev, ev, sig_state->pipe_hack[0],
- EVENT_FD_READ, signal_pipe_handler, NULL);
- }
- ev->num_signal_handlers++;
-
- return se;
-}
-
-
-/*
- check if a signal is pending
- return != 0 if a signal was pending
-*/
-int common_event_check_signal(struct event_context *ev)
-{
- int i;
-
- if (!sig_state || !SIG_PENDING(sig_state->got_signal)) {
- return 0;
- }
-
- for (i=0;i<NUM_SIGNALS+1;i++) {
- struct signal_event *se, *next;
- struct sigcounter counter = sig_state->signal_count[i];
- uint32_t count = sig_count(counter);
-
- if (count == 0) {
- continue;
- }
- for (se=sig_state->sig_handlers[i];se;se=next) {
- next = se->next;
-#ifdef SA_SIGINFO
- if (se->sa_flags & SA_SIGINFO) {
- int j;
- for (j=0;j<count;j++) {
- /* note the use of the sig_info array as a
- ring buffer */
- int ofs = ((count-1) + j) % SA_INFO_QUEUE_COUNT;
- se->handler(ev, se, i, 1,
- (void*)&sig_state->sig_info[i][ofs],
- se->private_data);
- }
- if (SIG_PENDING(sig_state->sig_blocked[i])) {
- /* we'd filled the queue, unblock the
- signal now */
- sigset_t set;
- sigemptyset(&set);
- sigaddset(&set, i);
- SIG_SEEN(sig_state->sig_blocked[i],
- sig_count(sig_state->sig_blocked[i]));
- sigprocmask(SIG_UNBLOCK, &set, NULL);
- }
- if (se->sa_flags & SA_RESETHAND) {
- talloc_free(se);
- }
- continue;
- }
-#endif
- se->handler(ev, se, i, count, NULL, se->private_data);
- if (se->sa_flags & SA_RESETHAND) {
- talloc_free(se);
- }
- }
- SIG_SEEN(sig_state->signal_count[i], count);
- SIG_SEEN(sig_state->got_signal, count);
- }
-
- return 1;
-}
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