前言

本節主要介紹 server 模塊進行初始化的代碼，關于初始化過程中，各個屬性的意義，可以參考官方文檔：

SERVER 配置選項

關于初始化過程中，用于監聽的 socket 綁定問題，可以參考：

UNP 學習筆記——基本 TCP 套接字編程

UNP 學習筆記——套接字選項

構造 server 對象

構造 server 對象最重要的是兩件事：swServer_init 初始化 server、為 server 添加端口：

PHP_METHOD(swoole_server, __construct) {zend_size_t host_len = 0;char *serv_host;long sock_type = SW_SOCK_TCP;long serv_port = 0;long serv_mode = SW_MODE_PROCESS;swServer *serv = sw_malloc(sizeof (swServer));swServer_init(serv);serv->factory_mode = serv_mode;if (serv_port == 0 && strcasecmp(serv_host, "SYSTEMD") == 0){if (swserver_add_systemd_socket(serv) <= 0){swoole_php_fatal_error(E_ERROR, "failed to add systemd socket.");return;}}else{swListenPort *port = swServer_add_port(serv, sock_type, serv_host, serv_port);} }

swServer_init 函數

• swServer_init 函數主要為 serv 對象賦值初值，如果想要更改 serv 對象各個屬性，可以調用 set 函數
• serv->gs 是全局共享內存

void swServer_init(swServer *serv) {swoole_init();bzero(serv, sizeof(swServer));serv->factory_mode = SW_MODE_BASE;serv->reactor_num = SW_REACTOR_NUM > SW_REACTOR_MAX_THREAD ? SW_REACTOR_MAX_THREAD : SW_REACTOR_NUM;serv->dispatch_mode = SW_DISPATCH_FDMOD;serv->worker_num = SW_CPU_NUM;serv->max_connection = SwooleG.max_sockets < SW_SESSION_LIST_SIZE ? SwooleG.max_sockets : SW_SESSION_LIST_SIZE;serv->max_request = 0;serv->max_wait_time = SW_WORKER_MAX_WAIT_TIME;//http serverserv->http_parse_post = 1;serv->upload_tmp_dir = sw_strdup("/tmp");//heartbeat checkserv->heartbeat_idle_time = SW_HEARTBEAT_IDLE;serv->heartbeat_check_interval = SW_HEARTBEAT_CHECK;serv->buffer_input_size = SW_BUFFER_INPUT_SIZE;serv->buffer_output_size = SW_BUFFER_OUTPUT_SIZE;serv->task_ipc_mode = SW_TASK_IPC_UNIXSOCK;/*** alloc shared memory*/serv->stats = SwooleG.memory_pool->alloc(SwooleG.memory_pool, sizeof(swServerStats));if (serv->stats == NULL){swError("[Master] Fatal Error: failed to allocate memory for swServer->stats.");}serv->gs = SwooleG.memory_pool->alloc(SwooleG.memory_pool, sizeof(swServerGS));if (serv->gs == NULL){swError("[Master] Fatal Error: failed to allocate memory for swServer->gs.");}SwooleG.serv = serv; }

swoole_init 函數

• swoole_init 函數用于初始化全局變量 SwooleG 的各個屬性
• SwooleGS 是全局的共享內存
• SwooleTG 是線程特有數據，每個線程都有自己獨特的數據

extern swServerG SwooleG; //Local Global Variable extern SwooleGS_t *SwooleGS; //Share Memory Global Variable extern __thread swThreadG SwooleTG; //Thread Global Variabletypedef struct {swLock lock;swLock lock_2; } SwooleGS_t;void swoole_init(void) {struct rlimit rlmt;if (SwooleG.running){return;}bzero(&SwooleG, sizeof(SwooleG));bzero(&SwooleWG, sizeof(SwooleWG));bzero(sw_error, SW_ERROR_MSG_SIZE);SwooleG.running = 1;SwooleG.enable_coroutine = 1;sw_errno = 0;SwooleG.log_fd = STDOUT_FILENO;SwooleG.cpu_num = sysconf(_SC_NPROCESSORS_ONLN);SwooleG.pagesize = getpagesize();SwooleG.pid = getpid();SwooleG.socket_buffer_size = SW_SOCKET_BUFFER_SIZE;#ifdef SW_DEBUGSwooleG.log_level = 0; #elseSwooleG.log_level = SW_LOG_INFO; #endif//get system unameuname(&SwooleG.uname);//random seedsrandom(time(NULL));//init global shared memorySwooleG.memory_pool = swMemoryGlobal_new(SW_GLOBAL_MEMORY_PAGESIZE, 1);if (SwooleG.memory_pool == NULL){printf("[Master] Fatal Error: global memory allocation failure.");exit(1);}SwooleGS = SwooleG.memory_pool->alloc(SwooleG.memory_pool, sizeof(SwooleGS_t));if (SwooleGS == NULL){printf("[Master] Fatal Error: failed to allocate memory for SwooleGS.");exit(2);}//init global lockswMutex_create(&SwooleGS->lock, 1);swMutex_create(&SwooleGS->lock_2, 1);swMutex_create(&SwooleG.lock, 0);if (getrlimit(RLIMIT_NOFILE, &rlmt) < 0){swWarn("getrlimit() failed. Error: %s[%d]", strerror(errno), errno);SwooleG.max_sockets = 1024;}else{SwooleG.max_sockets = (uint32_t) rlmt.rlim_cur;}SwooleTG.buffer_stack = swString_new(8192);if (SwooleTG.buffer_stack == NULL){exit(3);}if (!SwooleG.task_tmpdir){SwooleG.task_tmpdir = sw_strndup(SW_TASK_TMP_FILE, sizeof(SW_TASK_TMP_FILE));SwooleG.task_tmpdir_len = sizeof(SW_TASK_TMP_FILE);}char *tmp_dir = swoole_dirname(SwooleG.task_tmpdir);//create tmp dirif (access(tmp_dir, R_OK) < 0 && swoole_mkdir_recursive(tmp_dir) < 0){swWarn("create task tmp dir(%s) failed.", tmp_dir);}if (tmp_dir){sw_free(tmp_dir);}//init signalfd #ifdef HAVE_SIGNALFDswSignalfd_init();SwooleG.use_signalfd = 1;SwooleG.enable_signalfd = 1; #endif//timerfd #ifdef HAVE_TIMERFDSwooleG.use_timerfd = 1; #endifSwooleG.use_timer_pipe = 1; }

swServer_add_port 函數

• swServer_add_port 函數為服務端添加監聽的端口
• 首先需要檢測 listen_port_num 已監聽的端口不能大于 SW_MAX_LISTEN_PORT(默認為 60000)
• 如果 socket 的類型不是 unix sock，那么端口號必須大于等于 0，小于 65535
• host 主域名長度也不能大于 SW_HOST_MAXSIZE(104)
• 然后從共享內存池中申請一個 swListenPort 類型的對象，然后調用 swPort_init 對端口對象進行初始化
• 利用函數 swSocket_create 創建一個 socket 對象，并返回其文件描述符
• 調用 swSocket_bind 函數將 socket 綁定到對應的主域與端口上來
• 如果協議是數據報(UDP)，而不是數據流時，需要設置 socket 的發送緩存與接收緩存為 socket_buffer_size
• 設置 socket 為非阻塞、O_CLOEXEC(exec 之后文件描述符自動關閉)
• 根據協議類型設置 have_udp_sock、have_tcp_sock、udp_socket_ipv4/udp_socket_ipv6 等等屬性
• 遞增 listen_port_num ，向單鏈表 listen_list 中添加 swListenPort 對象

enum swSocket_type {SW_SOCK_TCP = 1,SW_SOCK_UDP = 2,SW_SOCK_TCP6 = 3,SW_SOCK_UDP6 = 4,SW_SOCK_UNIX_DGRAM = 5, //unix sock dgramSW_SOCK_UNIX_STREAM = 6, //unix sock stream };swListenPort* swServer_add_port(swServer *serv, int type, char *host, int port) {if (serv->listen_port_num >= SW_MAX_LISTEN_PORT){swoole_error_log(SW_LOG_ERROR, SW_ERROR_SERVER_TOO_MANY_LISTEN_PORT, "allows up to %d ports to listen", SW_MAX_LISTEN_PORT);return NULL;}if (!(type == SW_SOCK_UNIX_DGRAM || type == SW_SOCK_UNIX_STREAM) && (port < 0 || port > 65535)){swoole_error_log(SW_LOG_ERROR, SW_ERROR_SERVER_INVALID_LISTEN_PORT, "invalid port [%d]", port);return NULL;}if (strlen(host) + 1 > SW_HOST_MAXSIZE){swoole_error_log(SW_LOG_ERROR, SW_ERROR_NAME_TOO_LONG, "address '%s' exceeds %d characters limit", host, SW_HOST_MAXSIZE - 1);return NULL;}swListenPort *ls = SwooleG.memory_pool->alloc(SwooleG.memory_pool, sizeof(swListenPort));if (ls == NULL){swError("alloc failed");return NULL;}swPort_init(ls);ls->type = type;ls->port = port;strncpy(ls->host, host, strlen(host) + 1);if (type & SW_SOCK_SSL){type = type & (~SW_SOCK_SSL);if (swSocket_is_stream(type)){ls->type = type;ls->ssl = 1; #ifdef SW_USE_OPENSSLls->ssl_config.prefer_server_ciphers = 1;ls->ssl_config.session_tickets = 0;ls->ssl_config.stapling = 1;ls->ssl_config.stapling_verify = 1;ls->ssl_config.ciphers = sw_strdup(SW_SSL_CIPHER_LIST);ls->ssl_config.ecdh_curve = sw_strdup(SW_SSL_ECDH_CURVE); #endif}}//create server socketint sock = swSocket_create(ls->type);if (sock < 0){swSysError("create socket failed.");return NULL;}//bind address and portif (swSocket_bind(sock, ls->type, ls->host, &ls->port) < 0){close(sock);return NULL;}//dgram socket, setting socket buffer sizeif (swSocket_is_dgram(ls->type)){setsockopt(sock, SOL_SOCKET, SO_SNDBUF, &ls->socket_buffer_size, sizeof(int));setsockopt(sock, SOL_SOCKET, SO_RCVBUF, &ls->socket_buffer_size, sizeof(int));}//O_NONBLOCK & O_CLOEXECswoole_fcntl_set_option(sock, 1, 1);ls->sock = sock;if (swSocket_is_dgram(ls->type)){serv->have_udp_sock = 1;serv->dgram_port_num++;if (ls->type == SW_SOCK_UDP){serv->udp_socket_ipv4 = sock;}else if (ls->type == SW_SOCK_UDP6){serv->udp_socket_ipv6 = sock;}}else{serv->have_tcp_sock = 1;}LL_APPEND(serv->listen_list, ls);serv->listen_port_num++;return ls; }

swPort_init 函數

• swPort_init 函數用于初始化 swListenPort 對象
• backlog、tcp_keepcount、tcp_keepidle 等等都是相應 socket 的屬性
• 在外網通信時，有些客戶端發送數據的速度較慢，每次只能發送一小段數據。這樣 onReceive 到的數據就不是一個完整的包。 還有些客戶端是逐字節發送數據的，如果每次回調 onReceive 會拖慢整個系統。Length_Check 和 EOF_Check 的使用。package_length_type、package_eof 等等就是相關參數的具體參數。

#define SW_DATA_EOF "\r\n\r\n"void swPort_init(swListenPort *port) {port->sock = 0;port->ssl = 0;//listen backlogport->backlog = SW_BACKLOG;//tcp keepaliveport->tcp_keepcount = SW_TCP_KEEPCOUNT;port->tcp_keepinterval = SW_TCP_KEEPINTERVAL;port->tcp_keepidle = SW_TCP_KEEPIDLE;port->open_tcp_nopush = 1;port->protocol.package_length_type = 'N';port->protocol.package_length_size = 4;port->protocol.package_body_offset = 4;port->protocol.package_max_length = SW_BUFFER_INPUT_SIZE;port->socket_buffer_size = SwooleG.socket_buffer_size;char eof[] = SW_DATA_EOF;port->protocol.package_eof_len = sizeof(SW_DATA_EOF) - 1;memcpy(port->protocol.package_eof, eof, port->protocol.package_eof_len); }

• c：有符號、1字節
• C：無符號、1字節
• s ：有符號、主機字節序、2字節
• S：無符號、主機字節序、2字節
• n：無符號、網絡字節序、2字節
• N：無符號、網絡字節序、4字節
• l：有符號、主機字節序、4字節（小寫L）
• L：無符號、主機字節序、4字節（大寫L）
• v：無符號、小端字節序、2字節
• V：無符號、小端字節序、4字節

swSocket_create 創建 socket

swSocket_create 函數會根據 type 的類型來調用 socket 系統調用

int swSocket_create(int type) {int _domain;int _type;switch (type){case SW_SOCK_TCP:_domain = PF_INET;_type = SOCK_STREAM;break;case SW_SOCK_TCP6:_domain = PF_INET6;_type = SOCK_STREAM;break;case SW_SOCK_UDP:_domain = PF_INET;_type = SOCK_DGRAM;break;case SW_SOCK_UDP6:_domain = PF_INET6;_type = SOCK_DGRAM;break;case SW_SOCK_UNIX_DGRAM:_domain = PF_UNIX;_type = SOCK_DGRAM;break;case SW_SOCK_UNIX_STREAM:_domain = PF_UNIX;_type = SOCK_STREAM;break;default:swWarn("unknown socket type [%d]", type);return SW_ERR;}return socket(_domain, _type, 0); }

swSocket_bind 綁定端口

• SO_REUSEADDR 允許啟動一個監聽服務器并捆綁眾所周知端口，即使以前建立的該端口用作它們的本地端口的連接仍存在。

• • 如果不對TCP的套接字選項進行任何限制時，如果啟動兩個進程，第二個進程就會在調用bind函數的時候出錯（Address already in use）。
  • 如果在調用bind之前我們設置了SO_REUSEADDR，但是不在第二個進程啟動前close這個套接字，那么第二個進程仍然會在調用bind函數的時候出錯（Address already in use）。
  • 如果在調用bind之前我們設置了SO_REUSEADDR，并接收了一個客戶端連接，并且在第二個進程啟動前關閉了bind的套接字，這個時候第一個進程只擁有一個套接字（與客戶端的連接），那么第二個進程則可以bind成功，符合預期。
• 相對 SO_REUSEADDR 來說，SO_REUSEPORT 沒有那么多的限制條件，允許兩個毫無血緣關系的進程使用相同的 IP 地址同時監聽同一個端口，并且不會出現驚群效應
• 對于 UNIX SOCKET，需要設置 sun_family 與 sun_path
• 對于 IPV4，需要設置 sin_family、sin_port、sin_addr;對于 IPV6，需要設置 sin6_family、sin6_port、sin6_addr，然后調用 bind 函數;
• 如果 port 為0，說明服務器綁定的是任意端口，bind 函數會將系統所選擇的端口返回給 sockaddr 對象

int swSocket_bind(int sock, int type, char *host, int *port) {int ret;struct sockaddr_in addr_in4;struct sockaddr_in6 addr_in6;struct sockaddr_un addr_un;socklen_t len;//SO_REUSEADDR optionint option = 1;if (setsockopt(sock, SOL_SOCKET, SO_REUSEADDR, &option, sizeof(int)) < 0){swoole_error_log(SW_LOG_WARNING, SW_ERROR_SYSTEM_CALL_FAIL, "setsockopt(%d, SO_REUSEADDR) failed.", sock);}//reuse port #ifdef HAVE_REUSEPORTif (SwooleG.reuse_port){if (setsockopt(sock, SOL_SOCKET, SO_REUSEPORT, &option, sizeof(int)) < 0){swSysError("setsockopt(SO_REUSEPORT) failed.");SwooleG.reuse_port = 0;}} #endif//unix socketif (type == SW_SOCK_UNIX_DGRAM || type == SW_SOCK_UNIX_STREAM){bzero(&addr_un, sizeof(addr_un));unlink(host);addr_un.sun_family = AF_UNIX;strncpy(addr_un.sun_path, host, sizeof(addr_un.sun_path) - 1);ret = bind(sock, (struct sockaddr*) &addr_un, sizeof(addr_un));}//IPv6else if (type > SW_SOCK_UDP){bzero(&addr_in6, sizeof(addr_in6));inet_pton(AF_INET6, host, &(addr_in6.sin6_addr));addr_in6.sin6_port = htons(*port);addr_in6.sin6_family = AF_INET6;ret = bind(sock, (struct sockaddr *) &addr_in6, sizeof(addr_in6));if (ret == 0 && *port == 0){len = sizeof(addr_in6);if (getsockname(sock, (struct sockaddr *) &addr_in6, &len) != -1){*port = ntohs(addr_in6.sin6_port);}}}//IPv4else{bzero(&addr_in4, sizeof(addr_in4));inet_pton(AF_INET, host, &(addr_in4.sin_addr));addr_in4.sin_port = htons(*port);addr_in4.sin_family = AF_INET;ret = bind(sock, (struct sockaddr *) &addr_in4, sizeof(addr_in4));if (ret == 0 && *port == 0){len = sizeof(addr_in4);if (getsockname(sock, (struct sockaddr *) &addr_in4, &len) != -1){*port = ntohs(addr_in4.sin_port);}}}//bind failedif (ret < 0){swoole_error_log(SW_LOG_WARNING, SW_ERROR_SYSTEM_CALL_FAIL, "bind(%s:%d) failed. Error: %s [%d]", host, *port, strerror(errno), errno);return SW_ERR;}return ret; }

swoole_fcntl_set_option 函數為文件描述符設置選項

• 此函數主要是利用 fcntl 函數為文件描述符設置阻塞/非阻塞、CLOEXEC 等屬性。

void swoole_fcntl_set_option(int sock, int nonblock, int cloexec) {int opts, ret;if (nonblock >= 0){do{opts = fcntl(sock, F_GETFL);}while (opts < 0 && errno == EINTR);if (opts < 0){swSysError("fcntl(%d, GETFL) failed.", sock);}if (nonblock){opts = opts | O_NONBLOCK;}else{opts = opts & ~O_NONBLOCK;}do{ret = fcntl(sock, F_SETFL, opts);}while (ret < 0 && errno == EINTR);if (ret < 0){swSysError("fcntl(%d, SETFL, opts) failed.", sock);}}#ifdef FD_CLOEXECif (cloexec >= 0){do{opts = fcntl(sock, F_GETFD);}while (opts < 0 && errno == EINTR);if (opts < 0){swSysError("fcntl(%d, GETFL) failed.", sock);}if (cloexec){opts = opts | FD_CLOEXEC;}else{opts = opts & ~FD_CLOEXEC;}do{ret = fcntl(sock, F_SETFD, opts);}while (ret < 0 && errno == EINTR);if (ret < 0){swSysError("fcntl(%d, SETFD, opts) failed.", sock);}} #endif } 創作挑戰賽新人創作獎勵來咯，堅持創作打卡瓜分現金大獎

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