2 Unix SMB/CIFS implementation.
5 Copyright (C) Simo Sorce <idra@samba.org> 2011
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program. If not, see <http://www.gnu.org/licenses/>.
24 #include "system/time.h"
25 #include "system/shmem.h"
26 #include "system/filesys.h"
27 #include "server_prefork.h"
28 #include "../lib/util/samba_util.h"
29 #include "../lib/util/tevent_unix.h"
36 prefork_main_fn_t *main_fn;
40 struct pf_worker_data *pool;
44 prefork_sigchld_fn_t *sigchld_fn;
48 static bool prefork_setup_sigchld_handler(struct tevent_context *ev_ctx,
49 struct prefork_pool *pfp);
51 static int prefork_pool_destructor(struct prefork_pool *pfp)
53 anonymous_shared_free(pfp->pool);
57 bool prefork_create_pool(TALLOC_CTX *mem_ctx,
58 struct tevent_context *ev_ctx,
59 struct messaging_context *msg_ctx,
60 int listen_fd_size, int *listen_fds,
61 int min_children, int max_children,
62 prefork_main_fn_t *main_fn, void *private_data,
63 struct prefork_pool **pf_pool)
65 struct prefork_pool *pfp;
67 time_t now = time(NULL);
73 pfp = talloc_zero(mem_ctx, struct prefork_pool);
75 DEBUG(1, ("Out of memory!\n"));
78 pfp->listen_fd_size = listen_fd_size;
79 pfp->listen_fds = talloc_array(pfp, int, listen_fd_size);
80 if (!pfp->listen_fds) {
81 DEBUG(1, ("Out of memory!\n"));
84 for (i = 0; i < listen_fd_size; i++) {
85 pfp->listen_fds[i] = listen_fds[i];
86 /* force sockets in non-blocking mode */
87 set_blocking(listen_fds[i], false);
89 pfp->main_fn = main_fn;
90 pfp->private_data = private_data;
92 pfp->pool_size = max_children;
93 data_size = sizeof(struct pf_worker_data) * max_children;
95 pfp->pool = anonymous_shared_allocate(data_size);
96 if (pfp->pool == NULL) {
97 DEBUG(1, ("Failed to mmap memory for prefork pool!\n"));
101 talloc_set_destructor(pfp, prefork_pool_destructor);
103 for (i = 0; i < min_children; i++) {
105 pfp->pool[i].allowed_clients = 1;
106 pfp->pool[i].started = now;
111 DEBUG(1, ("Failed to prefork child n. %d !\n", i));
114 case 0: /* THE CHILD */
116 pfp->pool[i].status = PF_WORKER_ALIVE;
117 ret = pfp->main_fn(ev_ctx, msg_ctx,
118 &pfp->pool[i], i + 1,
124 default: /* THE PARENT */
125 pfp->pool[i].pid = pid;
130 ok = prefork_setup_sigchld_handler(ev_ctx, pfp);
132 DEBUG(1, ("Failed to setup SIGCHLD Handler!\n"));
141 /* Provide the new max children number in new_max
142 * (must be larger than current max).
143 * Returns: 0 if all fine
144 * ENOSPC if mremap fails to expand
145 * EINVAL if new_max is invalid
147 int prefork_expand_pool(struct prefork_pool *pfp, int new_max)
149 struct prefork_pool *pool;
154 if (new_max <= pfp->pool_size) {
158 old_size = sizeof(struct pf_worker_data) * pfp->pool_size;
159 new_size = sizeof(struct pf_worker_data) * new_max;
161 pool = anonymous_shared_resize(&pfp->pool, new_size, false);
164 DEBUG(3, ("Failed to mremap memory (%d: %s)!\n",
165 ret, strerror(ret)));
169 memset(&pool[pfp->pool_size], 0, new_size - old_size);
171 pfp->pool_size = new_max;
176 int prefork_add_children(struct tevent_context *ev_ctx,
177 struct messaging_context *msg_ctx,
178 struct prefork_pool *pfp,
182 time_t now = time(NULL);
186 for (i = 0, j = 0; i < pfp->pool_size && j < num_children; i++) {
188 if (pfp->pool[i].status != PF_WORKER_NONE) {
192 pfp->pool[i].allowed_clients = 1;
193 pfp->pool[i].started = now;
198 DEBUG(1, ("Failed to prefork child n. %d !\n", j));
201 case 0: /* THE CHILD */
203 pfp->pool[i].status = PF_WORKER_ALIVE;
204 ret = pfp->main_fn(ev_ctx, msg_ctx,
205 &pfp->pool[i], i + 1,
210 pfp->pool[i].status = PF_WORKER_EXITING;
213 default: /* THE PARENT */
214 pfp->pool[i].pid = pid;
220 DEBUG(5, ("Added %d children!\n", j));
225 struct prefork_oldest {
230 /* sort in inverse order */
231 static int prefork_sort_oldest(const void *ap, const void *bp)
233 const struct prefork_oldest *a = (const struct prefork_oldest *)ap;
234 const struct prefork_oldest *b = (const struct prefork_oldest *)bp;
236 if (a->started == b->started) {
239 if (a->started < b->started) {
245 int prefork_retire_children(struct messaging_context *msg_ctx,
246 struct prefork_pool *pfp,
247 int num_children, time_t age_limit)
249 const DATA_BLOB ping = data_blob_null;
250 time_t now = time(NULL);
251 struct prefork_oldest *oldest;
254 oldest = talloc_array(pfp, struct prefork_oldest, pfp->pool_size);
259 for (i = 0; i < pfp->pool_size; i++) {
261 if (pfp->pool[i].status == PF_WORKER_ALIVE ||
262 pfp->pool[i].status == PF_WORKER_ACCEPTING) {
263 oldest[i].started = pfp->pool[i].started;
265 oldest[i].started = now;
269 qsort(oldest, pfp->pool_size,
270 sizeof(struct prefork_oldest),
271 prefork_sort_oldest);
273 for (i = 0, j = 0; i < pfp->pool_size && j < num_children; i++) {
274 if (((pfp->pool[i].status == PF_WORKER_ALIVE) &&
275 (pfp->pool[i].num_clients < 1)) &&
276 (pfp->pool[i].started <= age_limit)) {
277 /* tell the child it's time to give up */
278 DEBUG(5, ("Retiring pid %d!\n", pfp->pool[i].pid));
279 pfp->pool[i].cmds = PF_SRV_MSG_EXIT;
280 messaging_send(msg_ctx,
281 pid_to_procid(pfp->pool[i].pid),
282 MSG_PREFORK_PARENT_EVENT, &ping);
290 int prefork_count_children(struct prefork_pool *pfp, int *active)
296 for (i = 0; i < pfp->pool_size; i++) {
297 if (pfp->pool[i].status == PF_WORKER_NONE) {
303 if ((pfp->pool[i].status == PF_WORKER_EXITING) ||
304 (pfp->pool[i].num_clients <= 0)) {
317 static void prefork_cleanup_loop(struct prefork_pool *pfp)
323 /* TODO: should we use a process group id wait instead of looping ? */
324 for (i = 0; i < pfp->pool_size; i++) {
325 if (pfp->pool[i].status == PF_WORKER_NONE ||
326 pfp->pool[i].pid == 0) {
330 pid = sys_waitpid(pfp->pool[i].pid, &status, WNOHANG);
333 if (pfp->pool[i].status != PF_WORKER_EXITING) {
334 DEBUG(3, ("Child (%d) terminated abnormally:"
335 " %d\n", (int)pid, status));
337 DEBUG(10, ("Child (%d) terminated with status:"
338 " %d\n", (int)pid, status));
342 * this makes status = PF_WORK_NONE */
343 memset(&pfp->pool[i], 0,
344 sizeof(struct pf_worker_data));
350 int prefork_count_allowed_connections(struct prefork_pool *pfp)
356 for (i = 0; i < pfp->pool_size; i++) {
357 if (pfp->pool[i].status == PF_WORKER_NONE ||
358 pfp->pool[i].status == PF_WORKER_EXITING) {
362 if (pfp->pool[i].num_clients < 0) {
366 c += pfp->pool[i].allowed_clients - pfp->pool[i].num_clients;
372 void prefork_increase_allowed_clients(struct prefork_pool *pfp, int max)
376 for (i = 0; i < pfp->pool_size; i++) {
377 if (pfp->pool[i].status == PF_WORKER_NONE ||
378 pfp->pool[i].status == PF_WORKER_EXITING) {
382 if (pfp->pool[i].num_clients < 0) {
386 if (pfp->pool[i].allowed_clients < max) {
387 pfp->pool[i].allowed_clients++;
392 void prefork_decrease_allowed_clients(struct prefork_pool *pfp)
396 for (i = 0; i < pfp->pool_size; i++) {
397 if (pfp->pool[i].status == PF_WORKER_NONE ||
398 pfp->pool[i].status == PF_WORKER_EXITING) {
402 if (pfp->pool[i].num_clients < 0) {
406 if (pfp->pool[i].allowed_clients > 1) {
407 pfp->pool[i].allowed_clients--;
412 void prefork_reset_allowed_clients(struct prefork_pool *pfp)
416 for (i = 0; i < pfp->pool_size; i++) {
417 pfp->pool[i].allowed_clients = 1;
421 void prefork_send_signal_to_all(struct prefork_pool *pfp, int signal_num)
425 for (i = 0; i < pfp->pool_size; i++) {
426 if (pfp->pool[i].status == PF_WORKER_NONE) {
430 kill(pfp->pool[i].pid, signal_num);
434 void prefork_warn_active_children(struct messaging_context *msg_ctx,
435 struct prefork_pool *pfp)
437 const DATA_BLOB ping = data_blob_null;
440 for (i = 0; i < pfp->pool_size; i++) {
441 if (pfp->pool[i].status == PF_WORKER_NONE) {
445 messaging_send(msg_ctx,
446 pid_to_procid(pfp->pool[i].pid),
447 MSG_PREFORK_PARENT_EVENT, &ping);
451 static void prefork_sigchld_handler(struct tevent_context *ev_ctx,
452 struct tevent_signal *se,
453 int signum, int count,
454 void *siginfo, void *pvt)
456 struct prefork_pool *pfp;
458 pfp = talloc_get_type_abort(pvt, struct prefork_pool);
460 /* run the cleanup function to make sure all dead children are
461 * properly and timely retired. */
462 prefork_cleanup_loop(pfp);
464 if (pfp->sigchld_fn) {
465 pfp->sigchld_fn(ev_ctx, pfp, pfp->sigchld_data);
469 static bool prefork_setup_sigchld_handler(struct tevent_context *ev_ctx,
470 struct prefork_pool *pfp)
472 struct tevent_signal *se;
474 se = tevent_add_signal(ev_ctx, pfp, SIGCHLD, 0,
475 prefork_sigchld_handler, pfp);
477 DEBUG(0, ("Failed to setup SIGCHLD handler!\n"));
484 void prefork_set_sigchld_callback(struct prefork_pool *pfp,
485 prefork_sigchld_fn_t *sigchld_fn,
488 pfp->sigchld_fn = sigchld_fn;
489 pfp->sigchld_data = private_data;
492 /* ==== Functions used by children ==== */
494 struct pf_listen_state {
495 struct tevent_context *ev;
496 struct pf_worker_data *pf;
503 struct tsocket_address *srv_addr;
504 struct tsocket_address *cli_addr;
509 struct pf_listen_ctx {
511 struct tevent_req *req;
515 static void prefork_listen_accept_handler(struct tevent_context *ev,
516 struct tevent_fd *fde,
517 uint16_t flags, void *pvt);
519 struct tevent_req *prefork_listen_send(TALLOC_CTX *mem_ctx,
520 struct tevent_context *ev,
521 struct pf_worker_data *pf,
525 struct tevent_req *req;
526 struct pf_listen_state *state;
527 struct pf_listen_ctx *ctx;
528 struct tevent_fd *fde;
532 req = tevent_req_create(mem_ctx, &state, struct pf_listen_state);
539 state->listen_fd_size = listen_fd_size;
540 state->listen_fds = listen_fds;
541 state->accept_fd = -1;
544 fde_ctx = talloc_new(state);
545 if (tevent_req_nomem(fde_ctx, req)) {
546 return tevent_req_post(req, ev);
550 for (i = 0; i < state->listen_fd_size; i++) {
551 ctx = talloc(fde_ctx, struct pf_listen_ctx);
552 if (tevent_req_nomem(ctx, req)) {
553 return tevent_req_post(req, ev);
555 ctx->fde_ctx = fde_ctx;
557 ctx->listen_fd = state->listen_fds[i];
559 fde = tevent_add_fd(state->ev, fde_ctx,
560 ctx->listen_fd, TEVENT_FD_READ,
561 prefork_listen_accept_handler, ctx);
562 if (tevent_req_nomem(fde, req)) {
563 return tevent_req_post(req, ev);
567 pf->status = PF_WORKER_ACCEPTING;
572 static void prefork_listen_accept_handler(struct tevent_context *ev,
573 struct tevent_fd *fde,
574 uint16_t flags, void *pvt)
576 struct pf_listen_state *state;
577 struct tevent_req *req;
578 struct pf_listen_ctx *ctx;
579 struct sockaddr_storage addr;
582 socklen_t solen = sizeof(soerr);
586 ctx = talloc_get_type_abort(pvt, struct pf_listen_ctx);
588 state = tevent_req_data(ctx->req, struct pf_listen_state);
590 if ((state->pf->cmds == PF_SRV_MSG_EXIT) &&
591 (state->pf->num_clients <= 0)) {
592 /* We have been asked to exit, so drop here and the next
593 * child will pick it up */
594 state->pf->status = PF_WORKER_EXITING;
595 state->error = EINTR;
599 /* before proceeding check that the listening fd is ok */
600 ret = getsockopt(ctx->listen_fd, SOL_SOCKET, SO_ERROR, &soerr, &solen);
602 /* this is a fatal error, we cannot continue listening */
603 state->error = EBADF;
607 /* this is a fatal error, we cannot continue listening */
608 state->error = soerr;
613 addrlen = sizeof(addr);
614 sd = accept(ctx->listen_fd, (struct sockaddr *)&addr, &addrlen);
616 state->error = errno;
617 DEBUG(6, ("Accept failed! (%d, %s)\n",
618 state->error, strerror(state->error)));
622 state->accept_fd = sd;
624 ret = tsocket_address_bsd_from_sockaddr(state,
625 (struct sockaddr *)(void *)&addr,
626 addrlen, &state->cli_addr);
628 state->error = errno;
633 addrlen = sizeof(addr);
634 ret = getsockname(sd, (struct sockaddr *)(void *)&addr, &addrlen);
636 state->error = errno;
640 ret = tsocket_address_bsd_from_sockaddr(state,
641 (struct sockaddr *)(void *)&addr,
642 addrlen, &state->srv_addr);
644 state->error = errno;
649 /* do not track the listen fds anymore */
650 talloc_free(ctx->fde_ctx);
651 tevent_req_done(req);
654 int prefork_listen_recv(struct tevent_req *req,
655 TALLOC_CTX *mem_ctx, int *fd,
656 struct tsocket_address **srv_addr,
657 struct tsocket_address **cli_addr)
659 struct pf_listen_state *state;
662 state = tevent_req_data(req, struct pf_listen_state);
667 tevent_req_is_unix_error(req, &ret);
671 if (state->accept_fd != -1) {
672 close(state->accept_fd);
675 *fd = state->accept_fd;
676 *srv_addr = talloc_move(mem_ctx, &state->srv_addr);
677 *cli_addr = talloc_move(mem_ctx, &state->cli_addr);
678 state->pf->num_clients++;
680 if (state->pf->status == PF_WORKER_ACCEPTING) {
681 state->pf->status = PF_WORKER_ALIVE;
684 tevent_req_received(req);