mpd/src/client.c
Max Kellermann d15e1e09a2 client: return early in client_new()
This saves one level of indent.
2008-08-28 20:03:03 +02:00

798 lines
20 KiB
C

/* the Music Player Daemon (MPD)
* Copyright (C) 2003-2007 by Warren Dukes (warren.dukes@gmail.com)
* This project's homepage is: http://www.musicpd.org
*
* 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include "client.h"
#include "command.h"
#include "conf.h"
#include "log.h"
#include "listen.h"
#include "permission.h"
#include "sllist.h"
#include "utils.h"
#include "ioops.h"
#include "myfprintf.h"
#include "os_compat.h"
#include "main_notify.h"
#include "../config.h"
#define GREETING "OK MPD " PROTOCOL_VERSION "\n"
#define CLIENT_MAX_BUFFER_LENGTH (40960)
#define CLIENT_LIST_MODE_BEGIN "command_list_begin"
#define CLIENT_LIST_OK_MODE_BEGIN "command_list_ok_begin"
#define CLIENT_LIST_MODE_END "command_list_end"
#define CLIENT_DEFAULT_OUT_BUFFER_SIZE (4096)
#define CLIENT_TIMEOUT_DEFAULT (60)
#define CLIENT_MAX_CONNECTIONS_DEFAULT (10)
#define CLIENT_MAX_COMMAND_LIST_DEFAULT (2048*1024)
#define CLIENT_MAX_OUTPUT_BUFFER_SIZE_DEFAULT (8192*1024)
/* set this to zero to indicate we have no possible clients */
static unsigned int client_max_connections; /*CLIENT_MAX_CONNECTIONS_DEFAULT; */
static int client_timeout = CLIENT_TIMEOUT_DEFAULT;
static size_t client_max_command_list_size =
CLIENT_MAX_COMMAND_LIST_DEFAULT;
static size_t client_max_output_buffer_size =
CLIENT_MAX_OUTPUT_BUFFER_SIZE_DEFAULT;
/* maybe make conf option for this, or... 32 might be good enough */
static long int client_list_cache_size = 32;
/* shared globally between all clients: */
static struct strnode *list_cache;
static struct strnode *list_cache_head;
static struct strnode *list_cache_tail;
struct client {
char buffer[CLIENT_MAX_BUFFER_LENGTH];
size_t bufferLength;
size_t bufferPos;
int fd; /* file descriptor */
int permission;
time_t lastTime;
struct strnode *cmd_list; /* for when in list mode */
struct strnode *cmd_list_tail; /* for when in list mode */
int cmd_list_OK; /* print OK after each command execution */
size_t cmd_list_size; /* mem cmd_list consumes */
int cmd_list_dup; /* has the cmd_list been copied to private space? */
struct sllnode *deferred_send; /* for output if client is slow */
size_t deferred_bytes; /* mem deferred_send consumes */
int expired; /* set whether this client should be closed on next
check of old clients */
unsigned int num; /* client number */
char *send_buf;
size_t send_buf_used; /* bytes used this instance */
size_t send_buf_size; /* bytes usable this instance */
size_t send_buf_alloc; /* bytes actually allocated */
};
static struct client *clients;
static void client_write_deferred(struct client *client);
static void client_write_output(struct client *client);
#ifdef SO_SNDBUF
static size_t get_default_snd_buf_size(struct client *client)
{
int new_size;
socklen_t sockOptLen = sizeof(int);
if (getsockopt(client->fd, SOL_SOCKET, SO_SNDBUF,
(char *)&new_size, &sockOptLen) < 0) {
DEBUG("problem getting sockets send buffer size\n");
return CLIENT_DEFAULT_OUT_BUFFER_SIZE;
}
if (new_size > 0)
return (size_t)new_size;
DEBUG("sockets send buffer size is not positive\n");
return CLIENT_DEFAULT_OUT_BUFFER_SIZE;
}
#else /* !SO_SNDBUF */
static size_t get_default_snd_buf_size(struct client *client)
{
return CLIENT_DEFAULT_OUT_BUFFER_SIZE;
}
#endif /* !SO_SNDBUF */
static void set_send_buf_size(struct client *client)
{
size_t new_size = get_default_snd_buf_size(client);
if (client->send_buf_size != new_size) {
client->send_buf_size = new_size;
/* don't resize to get smaller, only bigger */
if (client->send_buf_alloc < new_size) {
if (client->send_buf)
free(client->send_buf);
client->send_buf = xmalloc(new_size);
client->send_buf_alloc = new_size;
}
}
}
static void client_init(struct client *client, int fd)
{
assert(client->fd < 0);
client->cmd_list_size = 0;
client->cmd_list_dup = 0;
client->cmd_list_OK = -1;
client->bufferLength = 0;
client->bufferPos = 0;
client->fd = fd;
set_nonblocking(fd);
client->lastTime = time(NULL);
client->cmd_list = NULL;
client->cmd_list_tail = NULL;
client->deferred_send = NULL;
client->expired = 0;
client->deferred_bytes = 0;
client->send_buf_used = 0;
client->permission = getDefaultPermissions();
set_send_buf_size(client);
xwrite(fd, GREETING, strlen(GREETING));
}
static void free_cmd_list(struct strnode *list)
{
struct strnode *tmp = list;
while (tmp) {
struct strnode *next = tmp->next;
if (tmp >= list_cache_head && tmp <= list_cache_tail) {
/* inside list_cache[] array */
tmp->data = NULL;
tmp->next = NULL;
} else
free(tmp);
tmp = next;
}
}
static void cmd_list_clone(struct client *client)
{
struct strnode *new = dup_strlist(client->cmd_list);
free_cmd_list(client->cmd_list);
client->cmd_list = new;
client->cmd_list_dup = 1;
/* new tail */
while (new && new->next)
new = new->next;
client->cmd_list_tail = new;
}
static void new_cmd_list_ptr(struct client *client, char *s, const int size)
{
int i;
struct strnode *new;
if (!client->cmd_list_dup) {
for (i = client_list_cache_size - 1; i >= 0; --i) {
if (list_cache[i].data)
continue;
new = &(list_cache[i]);
new->data = s;
/* implied in free_cmd_list() and init: */
/* last->next->next = NULL; */
goto out;
}
}
/* allocate from the heap */
new = client->cmd_list_dup ? new_strnode_dup(s, size)
: new_strnode(s);
out:
if (client->cmd_list) {
client->cmd_list_tail->next = new;
client->cmd_list_tail = new;
} else
client->cmd_list = client->cmd_list_tail = new;
}
static void client_close(struct client *client)
{
struct sllnode *buf;
if (client->fd < 0)
return;
xclose(client->fd);
client->fd = -1;
if (client->cmd_list) {
free_cmd_list(client->cmd_list);
client->cmd_list = NULL;
}
if ((buf = client->deferred_send)) {
do {
struct sllnode *prev = buf;
buf = buf->next;
free(prev);
} while (buf);
client->deferred_send = NULL;
}
SECURE("client %i: closed\n", client->num);
}
void client_new(int fd, const struct sockaddr *addr)
{
unsigned int i;
const char *hostname;
for (i = 0; i < client_max_connections
&& clients[i].fd >= 0; i++) /* nothing */ ;
if (i == client_max_connections) {
ERROR("Max Connections Reached!\n");
xclose(fd);
return;
}
switch (addr->sa_family) {
#ifdef HAVE_TCP
case AF_INET:
hostname = (const char *)inet_ntoa(((const struct sockaddr_in *)
addr)->sin_addr);
if (!hostname)
hostname = "error getting ipv4 address";
break;
#ifdef HAVE_IPV6
case AF_INET6:
{
static char host[INET6_ADDRSTRLEN + 1];
memset(host, 0, INET6_ADDRSTRLEN + 1);
if (inet_ntop(AF_INET6, (const void *)
&(((const struct sockaddr_in6 *)addr)->
sin6_addr), host,
INET6_ADDRSTRLEN)) {
hostname = (const char *)host;
} else {
hostname = "error getting ipv6 address";
}
}
break;
#endif
#endif /* HAVE_TCP */
#ifdef HAVE_UN
case AF_UNIX:
hostname = "local connection";
break;
#endif /* HAVE_UN */
default:
hostname = "unknown";
}
SECURE("client %i: opened from %s\n", i, hostname);
client_init(&(clients[i]), fd);
}
static int client_process_line(struct client *client)
{
int ret = 1;
char *line = client->buffer + client->bufferPos;
if (client->cmd_list_OK >= 0) {
if (strcmp(line, CLIENT_LIST_MODE_END) == 0) {
DEBUG("client %i: process command "
"list\n", client->num);
ret = processListOfCommands(client->fd,
&(client->permission),
&(client->expired),
client->cmd_list_OK,
client->cmd_list);
DEBUG("client %i: process command "
"list returned %i\n", client->num, ret);
if (ret == 0)
commandSuccess(client->fd);
else if (ret == COMMAND_RETURN_CLOSE
|| client->expired)
client_close(client);
client_write_output(client);
free_cmd_list(client->cmd_list);
client->cmd_list = NULL;
client->cmd_list_OK = -1;
} else {
size_t len = strlen(line) + 1;
client->cmd_list_size += len;
if (client->cmd_list_size >
client_max_command_list_size) {
ERROR("client %i: command "
"list size (%lu) is "
"larger than the max "
"(%lu)\n",
client->num,
(unsigned long)client->cmd_list_size,
(unsigned long)
client_max_command_list_size);
client_close(client);
ret = COMMAND_RETURN_CLOSE;
} else
new_cmd_list_ptr(client, line, len);
}
} else {
if (strcmp(line, CLIENT_LIST_MODE_BEGIN) == 0) {
client->cmd_list_OK = 0;
ret = 1;
} else if (strcmp(line, CLIENT_LIST_OK_MODE_BEGIN) == 0) {
client->cmd_list_OK = 1;
ret = 1;
} else {
DEBUG("client %i: process command \"%s\"\n",
client->num, line);
ret = processCommand(client->fd,
&(client->permission), line);
DEBUG("client %i: command returned %i\n",
client->num, ret);
if (ret == 0)
commandSuccess(client->fd);
else if (ret == COMMAND_RETURN_CLOSE
|| client->expired) {
client_close(client);
}
client_write_output(client);
}
}
return ret;
}
static int client_input_received(struct client *client, int bytesRead)
{
int ret = 0;
char *buf_tail = &(client->buffer[client->bufferLength - 1]);
while (bytesRead > 0) {
client->bufferLength++;
bytesRead--;
buf_tail++;
if (*buf_tail == '\n') {
*buf_tail = '\0';
if (client->bufferLength > client->bufferPos) {
if (*(buf_tail - 1) == '\r')
*(buf_tail - 1) = '\0';
}
ret = client_process_line(client);
if (client->expired)
return ret;
client->bufferPos = client->bufferLength;
}
if (client->bufferLength == CLIENT_MAX_BUFFER_LENGTH) {
if (client->bufferPos == 0) {
ERROR("client %i: buffer overflow\n",
client->num);
client_close(client);
return 1;
}
if (client->cmd_list_OK >= 0 &&
client->cmd_list &&
!client->cmd_list_dup)
cmd_list_clone(client);
assert(client->bufferLength >= client->bufferPos
&& "bufferLength >= bufferPos");
client->bufferLength -= client->bufferPos;
memmove(client->buffer,
client->buffer + client->bufferPos,
client->bufferLength);
client->bufferPos = 0;
}
if (ret == COMMAND_RETURN_KILL || ret == COMMAND_RETURN_CLOSE) {
return ret;
}
}
return ret;
}
static int client_read(struct client *client)
{
int bytesRead;
bytesRead = read(client->fd,
client->buffer + client->bufferLength,
CLIENT_MAX_BUFFER_LENGTH - client->bufferLength);
if (bytesRead > 0)
return client_input_received(client, bytesRead);
else if (bytesRead == 0 || (bytesRead < 0 && errno != EINTR)) {
client_close(client);
} else
return 0;
return 1;
}
static void client_manager_register_read_fd(fd_set * fds, int *fdmax)
{
unsigned int i;
FD_ZERO(fds);
addListenSocketsToFdSet(fds, fdmax);
for (i = 0; i < client_max_connections; i++) {
if (clients[i].fd >= 0 && !clients[i].expired
&& !clients[i].deferred_send) {
FD_SET(clients[i].fd, fds);
if (*fdmax < clients[i].fd)
*fdmax = clients[i].fd;
}
}
}
static void client_manager_register_write_fd(fd_set * fds, int *fdmax)
{
unsigned int i;
FD_ZERO(fds);
for (i = 0; i < client_max_connections; i++) {
if (clients[i].fd >= 0 && !clients[i].expired
&& clients[i].deferred_send) {
FD_SET(clients[i].fd, fds);
if (*fdmax < clients[i].fd)
*fdmax = clients[i].fd;
}
}
}
static void closeNextErroredInterface(void)
{
fd_set fds;
struct timeval tv;
unsigned int i;
tv.tv_sec = 0;
tv.tv_usec = 0;
for (i = 0; i < client_max_connections; i++) {
if (clients[i].fd >= 0) {
FD_ZERO(&fds);
FD_SET(clients[i].fd, &fds);
if (select(clients[i].fd + 1,
&fds, NULL, NULL, &tv) < 0) {
client_close(&clients[i]);
return;
}
}
}
}
int client_manager_io(void)
{
fd_set rfds;
fd_set wfds;
fd_set efds;
unsigned int i;
int selret;
int fdmax;
while (1) {
fdmax = 0;
FD_ZERO( &efds );
client_manager_register_read_fd(&rfds, &fdmax);
client_manager_register_write_fd(&wfds, &fdmax);
registered_IO_add_fds(&fdmax, &rfds, &wfds, &efds);
main_notify_lock();
selret = select(fdmax + 1, &rfds, &wfds, &efds, NULL);
main_notify_unlock();
if (selret < 0 && errno == EINTR)
break;
registered_IO_consume_fds(&selret, &rfds, &wfds, &efds);
if (selret == 0)
break;
if (selret < 0) {
closeNextErroredInterface();
continue;
}
getConnections(&rfds);
for (i = 0; i < client_max_connections; i++) {
if (clients[i].fd >= 0
&& FD_ISSET(clients[i].fd, &rfds)) {
if (COMMAND_RETURN_KILL ==
client_read(&(clients[i]))) {
return COMMAND_RETURN_KILL;
}
clients[i].lastTime = time(NULL);
}
if (clients[i].fd >= 0
&& FD_ISSET(clients[i].fd, &wfds)) {
client_write_deferred(&clients[i]);
clients[i].lastTime = time(NULL);
}
}
break;
}
return 1;
}
void client_manager_init(void)
{
unsigned int i;
char *test;
ConfigParam *param;
param = getConfigParam(CONF_CONN_TIMEOUT);
if (param) {
client_timeout = strtol(param->value, &test, 10);
if (*test != '\0' || client_timeout <= 0) {
FATAL("connection timeout \"%s\" is not a positive "
"integer, line %i\n", CONF_CONN_TIMEOUT,
param->line);
}
}
param = getConfigParam(CONF_MAX_CONN);
if (param) {
client_max_connections = strtol(param->value, &test, 10);
if (*test != '\0' || client_max_connections <= 0) {
FATAL("max connections \"%s\" is not a positive integer"
", line %i\n", param->value, param->line);
}
} else
client_max_connections = CLIENT_MAX_CONNECTIONS_DEFAULT;
param = getConfigParam(CONF_MAX_COMMAND_LIST_SIZE);
if (param) {
long tmp = strtol(param->value, &test, 10);
if (*test != '\0' || tmp <= 0) {
FATAL("max command list size \"%s\" is not a positive "
"integer, line %i\n", param->value, param->line);
}
client_max_command_list_size = tmp * 1024;
}
param = getConfigParam(CONF_MAX_OUTPUT_BUFFER_SIZE);
if (param) {
long tmp = strtol(param->value, &test, 10);
if (*test != '\0' || tmp <= 0) {
FATAL("max output buffer size \"%s\" is not a positive "
"integer, line %i\n", param->value, param->line);
}
client_max_output_buffer_size = tmp * 1024;
}
clients = xmalloc(sizeof(clients[0]) * client_max_connections);
list_cache = xcalloc(client_list_cache_size, sizeof(struct strnode));
list_cache_head = &(list_cache[0]);
list_cache_tail = &(list_cache[client_list_cache_size - 1]);
for (i = 0; i < client_max_connections; i++) {
clients[i].fd = -1;
clients[i].send_buf = NULL;
clients[i].send_buf_size = 0;
clients[i].send_buf_alloc = 0;
clients[i].num = i;
}
}
static void client_close_all(void)
{
unsigned int i;
for (i = 0; i < client_max_connections; i++) {
if (clients[i].fd >= 0)
client_close(&(clients[i]));
if (clients[i].send_buf)
free(clients[i].send_buf);
}
free(list_cache);
}
void client_manager_deinit(void)
{
client_close_all();
free(clients);
client_max_connections = 0;
}
void client_manager_expire(void)
{
unsigned int i;
for (i = 0; i < client_max_connections; i++) {
if (clients[i].fd >= 0) {
if (clients[i].expired) {
DEBUG("client %i: expired\n", i);
client_close(&(clients[i]));
} else if (time(NULL) - clients[i].lastTime >
client_timeout) {
DEBUG("client %i: timeout\n", i);
client_close(&(clients[i]));
}
}
}
}
static void client_write_deferred(struct client *client)
{
struct sllnode *buf;
ssize_t ret = 0;
buf = client->deferred_send;
while (buf) {
ret = write(client->fd, buf->data, buf->size);
if (ret < 0)
break;
else if ((size_t)ret < buf->size) {
assert(client->deferred_bytes >= (size_t)ret);
client->deferred_bytes -= ret;
buf->data = (char *)buf->data + ret;
buf->size -= ret;
} else {
struct sllnode *tmp = buf;
size_t decr = (buf->size + sizeof(struct sllnode));
assert(client->deferred_bytes >= decr);
client->deferred_bytes -= decr;
buf = buf->next;
free(tmp);
client->deferred_send = buf;
}
client->lastTime = time(NULL);
}
if (!client->deferred_send) {
DEBUG("client %i: buffer empty %lu\n", client->num,
(unsigned long)client->deferred_bytes);
assert(client->deferred_bytes == 0);
} else if (ret < 0 && errno != EAGAIN && errno != EINTR) {
/* cause client to close */
DEBUG("client %i: problems flushing buffer\n",
client->num);
buf = client->deferred_send;
do {
struct sllnode *prev = buf;
buf = buf->next;
free(prev);
} while (buf);
client->deferred_send = NULL;
client->deferred_bytes = 0;
client->expired = 1;
}
}
int client_print(int fd, const char *buffer, size_t buflen)
{
static unsigned int i;
size_t copylen;
struct client *client;
assert(fd >= 0);
if (i >= client_max_connections ||
clients[i].fd < 0 || clients[i].fd != fd) {
for (i = 0; i < client_max_connections; i++) {
if (clients[i].fd == fd)
break;
}
if (i == client_max_connections)
return -1;
}
/* if fd isn't found or client is going to be closed, do nothing */
if (clients[i].expired)
return 0;
client = clients + i;
while (buflen > 0 && !client->expired) {
size_t left;
assert(client->send_buf_size >= client->send_buf_used);
left = client->send_buf_size - client->send_buf_used;
copylen = buflen > left ? left : buflen;
memcpy(client->send_buf + client->send_buf_used, buffer,
copylen);
buflen -= copylen;
client->send_buf_used += copylen;
buffer += copylen;
if (client->send_buf_used >= client->send_buf_size)
client_write_output(client);
}
return 0;
}
static void client_write_output(struct client *client)
{
ssize_t ret;
struct sllnode *buf;
if (client->fd < 0 || client->expired ||
!client->send_buf_used)
return;
if ((buf = client->deferred_send)) {
client->deferred_bytes += sizeof(struct sllnode)
+ client->send_buf_used;
if (client->deferred_bytes >
client_max_output_buffer_size) {
ERROR("client %i: output buffer size (%lu) is "
"larger than the max (%lu)\n",
client->num,
(unsigned long)client->deferred_bytes,
(unsigned long)client_max_output_buffer_size);
/* cause client to close */
client->expired = 1;
do {
struct sllnode *prev = buf;
buf = buf->next;
free(prev);
} while (buf);
client->deferred_send = NULL;
client->deferred_bytes = 0;
} else {
while (buf->next)
buf = buf->next;
buf->next = new_sllnode(client->send_buf,
client->send_buf_used);
}
} else {
if ((ret = write(client->fd, client->send_buf,
client->send_buf_used)) < 0) {
if (errno == EAGAIN || errno == EINTR) {
client->deferred_send =
new_sllnode(client->send_buf,
client->send_buf_used);
} else {
DEBUG("client %i: problems writing\n",
client->num);
client->expired = 1;
return;
}
} else if ((size_t)ret < client->send_buf_used) {
client->deferred_send =
new_sllnode(client->send_buf + ret,
client->send_buf_used - ret);
}
if (client->deferred_send) {
DEBUG("client %i: buffer created\n", client->num);
client->deferred_bytes =
client->deferred_send->size
+ sizeof(struct sllnode);
}
}
client->send_buf_used = 0;
}