tinyproxy/src/child.c

312 lines
8.9 KiB
C

/* tinyproxy - A fast light-weight HTTP proxy
* Copyright (C) 2000 Robert James Kaes <rjkaes@users.sourceforge.net>
*
* 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 2 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, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
/* Handles the creation/destruction of the various children required for
* processing incoming connections.
*/
#include "main.h"
#include "child.h"
#include "daemon.h"
#include "filter.h"
#include "heap.h"
#include "log.h"
#include "reqs.h"
#include "sock.h"
#include "utils.h"
#include "conf.h"
#include "sblist.h"
#include "loop.h"
#include "conns.h"
#include "mypoll.h"
#include <pthread.h>
static sblist* listen_fds;
struct client {
union sockaddr_union addr;
};
struct child {
pthread_t thread;
struct client client;
struct conn_s conn;
volatile int done;
};
static void* child_thread(void* data)
{
struct child *c = data;
handle_connection (&c->conn, &c->client.addr);
c->done = 1;
return NULL;
}
static sblist *childs;
static void collect_threads(void)
{
size_t i;
for (i = 0; i < sblist_getsize(childs); ) {
struct child *c = *((struct child**)sblist_get(childs, i));
if (c->done) {
pthread_join(c->thread, 0);
sblist_delete(childs, i);
safefree(c);
} else i++;
}
}
/*
* This is the main loop accepting new connections.
*/
void child_main_loop (void)
{
int connfd;
union sockaddr_union cliaddr_storage;
struct sockaddr *cliaddr = (void*) &cliaddr_storage;
socklen_t clilen = sizeof(cliaddr_storage);
int nfds = sblist_getsize(listen_fds);
pollfd_struct *fds = safecalloc(nfds, sizeof *fds);
ssize_t i;
int ret, listenfd, was_full = 0;
pthread_attr_t *attrp, attr;
struct child *child;
childs = sblist_new(sizeof (struct child*), config->maxclients);
for (i = 0; i < nfds; i++) {
int *fd = sblist_get(listen_fds, i);
fds[i].fd = *fd;
fds[i].events |= MYPOLL_READ;
}
/*
* We have to wait for connections on multiple fds,
* so use select/poll/whatever.
*/
while (!config->quit) {
collect_threads();
if (sblist_getsize(childs) >= config->maxclients) {
if (!was_full)
log_message (LOG_WARNING,
"Maximum number of connections reached. "
"Refusing new connections.");
was_full = 1;
usleep(16);
continue;
}
was_full = 0;
listenfd = -1;
/* Handle log rotation if it was requested */
if (received_sighup) {
reload_config (1);
#ifdef FILTER_ENABLE
filter_reload ();
#endif /* FILTER_ENABLE */
received_sighup = FALSE;
}
ret = mypoll(fds, nfds, -1);
if (ret == -1) {
if (errno == EINTR) {
continue;
}
log_message (LOG_ERR, "error calling " SELECT_OR_POLL ": %s",
strerror(errno));
continue;
} else if (ret == 0) {
log_message (LOG_WARNING, "Strange: " SELECT_OR_POLL " returned 0 "
"but we did not specify a timeout...");
continue;
}
for (i = 0; i < nfds; i++) {
if (fds[i].revents & MYPOLL_READ) {
/*
* only accept the connection on the first
* fd that we find readable. - fair?
*/
listenfd = fds[i].fd;
break;
}
}
if (listenfd == -1) {
log_message(LOG_WARNING, "Strange: None of our listen "
"fds was readable after " SELECT_OR_POLL);
continue;
}
/*
* We have a socket that is readable.
* Continue handling this connection.
*/
connfd = accept (listenfd, cliaddr, &clilen);
/*
* Make sure no error occurred...
*/
if (connfd < 0) {
log_message (LOG_ERR,
"Accept returned an error (%s) ... retrying.",
strerror (errno));
continue;
}
child = safecalloc(1, sizeof(struct child));
if (!child) {
oom:
close(connfd);
log_message (LOG_CRIT,
"Could not allocate memory for child.");
usleep(16); /* prevent 100% CPU usage in OOM situation */
continue;
}
child->done = 0;
if (!sblist_add(childs, &child)) {
free(child);
goto oom;
}
conn_struct_init(&child->conn);
child->conn.client_fd = connfd;
memcpy(&child->client.addr, &cliaddr_storage, sizeof(cliaddr_storage));
attrp = 0;
if (pthread_attr_init(&attr) == 0) {
attrp = &attr;
pthread_attr_setstacksize(attrp, 256*1024);
}
if (pthread_create(&child->thread, attrp, child_thread, child) != 0) {
sblist_delete(childs, sblist_getsize(childs) -1);
free(child);
goto oom;
}
}
safefree(fds);
}
/*
* Go through all the non-empty children and cancel them.
*/
void child_kill_children (int sig)
{
size_t i;
if (sig != SIGTERM) return;
for (i = 0; i < sblist_getsize(childs); i++) {
struct child *c = *((struct child**)sblist_get(childs, i));
if (!c->done) {
/* interrupt blocking operations.
this should cause the threads to shutdown orderly. */
close(c->conn.client_fd);
}
}
usleep(16);
collect_threads();
if (sblist_getsize(childs) != 0)
log_message (LOG_CRIT,
"child_kill_children: %zu threads still alive!",
sblist_getsize(childs)
);
}
void child_free_children(void) {
sblist_free(childs);
childs = 0;
}
/**
* Listen on the various configured interfaces
*/
int child_listening_sockets(sblist *listen_addrs, uint16_t port)
{
int ret;
size_t i;
assert (port > 0);
if (listen_fds == NULL) {
listen_fds = sblist_new(sizeof(int), 16);
if (listen_fds == NULL) {
log_message (LOG_ERR, "Could not create the list "
"of listening fds");
return -1;
}
}
if (!listen_addrs || !sblist_getsize(listen_addrs))
{
/*
* no Listen directive:
* listen on the wildcard address(es)
*/
ret = listen_sock(NULL, port, listen_fds);
return ret;
}
for (i = 0; i < sblist_getsize(listen_addrs); i++) {
char **addr;
addr = sblist_get(listen_addrs, i);
if (!addr || !*addr) {
log_message(LOG_WARNING,
"got NULL from listen_addrs - skipping");
continue;
}
ret = listen_sock(*addr, port, listen_fds);
if (ret != 0) {
return ret;
}
}
return 0;
}
void child_close_sock (void)
{
size_t i;
for (i = 0; i < sblist_getsize(listen_fds); i++) {
int *fd = sblist_get(listen_fds, i);
close (*fd);
}
sblist_free(listen_fds);
listen_fds = NULL;
}