reactor(百万并发服务器)

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http://t.csdnimg.cn/Os83Qhttp://t.csdnimg.cn/Os83Q这篇文章将我们的reactro转变成http服务器...

HTTP

HTTP介绍

HTTP是一个基于TCP通信协议的基础上的应用层协议。接下来我们需要解析HTTP请求消息、根据业务对数据进行处理、封装HTTP响应消息发出去。

HTTP请求消息格式

        客户端发送一个 HTTP 请求到服务器的请求消息包括以下格式：请求行（request line）、请求头部（header）、空行和请求数据四个部分组成，下图给出了请求报文的一般格式。

HTTP响应消息格式

        HTTP 响应由四个部分组成，分别是：状态行、消息报头、空行和响应正文。

HTTP业务流程

        HTTP请求消息格式里面的URL就是客户端要想的资源，例如这里就是index.html。所以我们需要从浏览器发来的请求中，把url解析出来，这是第一步；解析出来请求的资源后我们需要去查找服务器是否存在该资源，如果有则状态200，如果没有则404Not Found，这是第二步；我们观察到有个Accpet字段，这是浏览器想要获得资源的类型，所以我们响应发回的响应消息里面，要根据请求的资源，填充Content-Type字段，这是第三步；还有一个需要注意的点，Content-Length字段是根据响应正文（请求的资源）的大小来计算的，我们需要计算资源大小并填充Content-Length字段，这是第四步。至此，响应头就组装好了，后面再按照格式加个换行，最后再把资源发过去就行了。

代码补充

recv_cb修改

int readline(char *allbuf, int idx, char *linebuf) {uint len = strlen(allbuf);for (; idx < len; idx++) {if (allbuf[idx] == '\r' && allbuf[idx + 1] == '\n') {return idx + 2;}else {*(linebuf++) = allbuf[idx];}}return -1;
}int http_request(struct ntyevent *ev) {char line_buffer[1024] = {0};readline(ev->buffer, 0, line_buffer);if (strstr(line_buffer, "GET")) {ev->method = HTTP_METHOD_GET;//uriint i = 0;while (line_buffer[sizeof("GET ") + i] != ' ') i++;line_buffer[sizeof("GET ") + i] = '\0';sprintf(ev->resource, "./%s/%s", HTTP_WEBSERVER_HTML_ROOT, line_buffer + sizeof("GET "));//Content-Typeif (strstr(line_buffer + sizeof("GET "), ".")) {char *type = strchr(line_buffer + sizeof("GET "), '.') + 1;if (strcmp(type, "html") == 0 || strcmp(type, "css") == 0) {sprintf(ev->Content_Type, "text/%s", type);}else if (strcmp(type, "jpg") == 0 || strcmp(type, "png") == 0 || strcmp(type, "ico") == 0) {sprintf(ev->Content_Type, "image/%s", type);}}else {sprintf(ev->Content_Type, "text/html");}}
}int recv_cb(int fd, int events, void *arg) {struct ntyreactor *reactor = (struct ntyreactor *) arg;struct ntyevent *ev = ntyreactor_find_event_idx(reactor, fd);int len = recv(fd, ev->buffer, BUFFER_LENGTH, 0); //nty_event_del(reactor->epfd, ev);if (len > 0) {ev->length = len;ev->buffer[len] = '\0';printf("[socket fd=%d recv]\n%s\n", fd, ev->buffer); //httphttp_request(ev);nty_event_set(ev, fd, send_cb, reactor);nty_event_add(reactor->epfd, EPOLLOUT, ev);}else if (len == 0) {close(ev->fd);}else {close(ev->fd);}return len;
}

send_cb修改

int http_response(struct ntyevent *ev) {if (ev == NULL) return -1;memset(ev->buffer, 0, BUFFER_LENGTH);int filefd = open(ev->resource, O_RDONLY);if (filefd == -1) { // return 404ev->ret_code = 404;ev->length = sprintf(ev->buffer,"HTTP/1.1 404 Not Found\r\n""Content-Type: %s;charset=utf-8\r\n""Content-Length: 83\r\n\r\n""<html><head><title>404 Not Found</title></head><body><H1>404</H1></body></html>\r\n\r\n",ev->Content_Type);}else {struct stat stat_buf;fstat(filefd, &stat_buf);close(filefd);if (S_ISDIR(stat_buf.st_mode)) {ev->ret_code = 404;ev->length = sprintf(ev->buffer,"HTTP/1.1 404 Not Found\r\n""Content-Type: %s;charset=utf-8\r\n""Content-Length: 83\r\n\r\n""<html><head><title>404 Not Found</title></head><body><H1>404</H1></body></html>\r\n\r\n",ev->Content_Type);}else if (S_ISREG(stat_buf.st_mode)) {ev->ret_code = 200;ev->length = sprintf(ev->buffer,"HTTP/1.1 200 OK\r\n""Content-Type: %s;charset=utf-8\r\n""Content-Length: %ld\r\n\r\n",ev->Content_Type, stat_buf.st_size);}}return ev->length;
}int send_cb(int fd, int events, void *arg) {struct ntyreactor *reactor = (struct ntyreactor *) arg;struct ntyevent *ev = ntyreactor_find_event_idx(reactor, fd);http_response(ev);printf("[socket fd=%d count=%d]\n%s", fd, ev->length, ev->buffer);int res_head_len = send(fd, ev->buffer, ev->length, 0);if (res_head_len > 0) {if (ev->ret_code == 200) {int filefd = open(ev->resource, O_RDONLY);struct stat stat_buf;fstat(filefd, &stat_buf);off_t offset = 0;while (offset != stat_buf.st_size) {int n = sendfile(fd, filefd, &offset, (stat_buf.st_size - offset));if (n == -1 && errno == EAGAIN) {usleep(5000);continue;}}printf("[resource: %s count:%ld]\r\n", ev->resource, offset);close(filefd);}nty_event_del(reactor->epfd, ev);nty_event_set(ev, fd, recv_cb, reactor);nty_event_add(reactor->epfd, EPOLLIN, ev);}else {nty_event_del(reactor->epfd, ev);close(ev->fd);}return 0;
}

sendfile

有时候我们发送的资源可能是图片、文本等，所以我们需要提供这样的方法。

int filefd = open(ev->resource, O_RDONLY);
struct stat stat_buf;
fstat(filefd, &stat_buf);
off_t offset = 0;
while (offset != stat_buf.st_size) {int n = sendfile(fd, filefd, &offset, (stat_buf.st_size - offset));if (n == -1 && errno == EAGAIN) {usleep(5000);continue;}
}
printf("[resource: %s count:%ld]\r\n", ev->resource, offset);
close(filefd);

完整代码

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/epoll.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <sys/stat.h>
#include <sys/sendfile.h>#define BUFFER_LENGTH           4096
#define MAX_EPOLL_EVENTS        1024
#define SERVER_PORT             8080
#define PORT_COUNT              100
#define HTTP_METHOD_GET        0
#define HTTP_METHOD_POST    1
#define HTTP_WEBSERVER_HTML_ROOT    "html"typedef int (*NCALLBACK)(int, int, void *);struct ntyevent {int fd;int events;void *arg;NCALLBACK callback;int status;char buffer[BUFFER_LENGTH];int length;//http paramint method; //char resource[BUFFER_LENGTH];int ret_code;char Content_Type[512];
};
struct eventblock {struct eventblock *next;struct ntyevent *events;
};struct ntyreactor {int epfd;int blkcnt;struct eventblock *evblk;
};int recv_cb(int fd, int events, void *arg);int send_cb(int fd, int events, void *arg);struct ntyevent *ntyreactor_find_event_idx(struct ntyreactor *reactor, int sockfd);void nty_event_set(struct ntyevent *ev, int fd, NCALLBACK callback, void *arg) {ev->fd = fd;ev->callback = callback;ev->events = 0;ev->arg = arg;
}int nty_event_add(int epfd, int events, struct ntyevent *ev) {struct epoll_event ep_ev = {0, {0}};ep_ev.data.ptr = ev;ep_ev.events = ev->events = events;int op;if (ev->status == 1) {op = EPOLL_CTL_MOD;}else {op = EPOLL_CTL_ADD;ev->status = 1;}if (epoll_ctl(epfd, op, ev->fd, &ep_ev) < 0) {printf("event add failed [fd=%d], events[%d]\n", ev->fd, events);return -1;}return 0;
}int nty_event_del(int epfd, struct ntyevent *ev) {struct epoll_event ep_ev = {0, {0}};if (ev->status != 1) {return -1;}ep_ev.data.ptr = ev;ev->status = 0;epoll_ctl(epfd, EPOLL_CTL_DEL, ev->fd, &ep_ev);return 0;
}int readline(char *allbuf, int idx, char *linebuf) {uint len = strlen(allbuf);for (; idx < len; idx++) {if (allbuf[idx] == '\r' && allbuf[idx + 1] == '\n') {return idx + 2;}else {*(linebuf++) = allbuf[idx];}}return -1;
}int http_request(struct ntyevent *ev) {char line_buffer[1024] = {0};readline(ev->buffer, 0, line_buffer);if (strstr(line_buffer, "GET")) {ev->method = HTTP_METHOD_GET;//uriint i = 0;while (line_buffer[sizeof("GET ") + i] != ' ') i++;line_buffer[sizeof("GET ") + i] = '\0';sprintf(ev->resource, "./%s/%s", HTTP_WEBSERVER_HTML_ROOT, line_buffer + sizeof("GET "));//Content-Typeif (strstr(line_buffer + sizeof("GET "), ".")) {char *type = strchr(line_buffer + sizeof("GET "), '.') + 1;if (strcmp(type, "html") == 0 || strcmp(type, "css") == 0) {sprintf(ev->Content_Type, "text/%s", type);}else if (strcmp(type, "jpg") == 0 || strcmp(type, "png") == 0 || strcmp(type, "ico") == 0) {sprintf(ev->Content_Type, "image/%s", type);}}else {sprintf(ev->Content_Type, "text/html");}}
}int recv_cb(int fd, int events, void *arg) {struct ntyreactor *reactor = (struct ntyreactor *) arg;struct ntyevent *ev = ntyreactor_find_event_idx(reactor, fd);int len = recv(fd, ev->buffer, BUFFER_LENGTH, 0); //nty_event_del(reactor->epfd, ev);if (len > 0) {ev->length = len;ev->buffer[len] = '\0';printf("[socket fd=%d recv]\n%s\n", fd, ev->buffer); //httphttp_request(ev);nty_event_set(ev, fd, send_cb, reactor);nty_event_add(reactor->epfd, EPOLLOUT, ev);}else if (len == 0) {close(ev->fd);}else {close(ev->fd);}return len;
}int http_response(struct ntyevent *ev) {if (ev == NULL) return -1;memset(ev->buffer, 0, BUFFER_LENGTH);int filefd = open(ev->resource, O_RDONLY);if (filefd == -1) { // return 404ev->ret_code = 404;ev->length = sprintf(ev->buffer,"HTTP/1.1 404 Not Found\r\n""Content-Type: %s;charset=utf-8\r\n""Content-Length: 83\r\n\r\n""<html><head><title>404 Not Found</title></head><body><H1>404</H1></body></html>\r\n\r\n",ev->Content_Type);}else {struct stat stat_buf;fstat(filefd, &stat_buf);close(filefd);if (S_ISDIR(stat_buf.st_mode)) {ev->ret_code = 404;ev->length = sprintf(ev->buffer,"HTTP/1.1 404 Not Found\r\n""Content-Type: %s;charset=utf-8\r\n""Content-Length: 83\r\n\r\n""<html><head><title>404 Not Found</title></head><body><H1>404</H1></body></html>\r\n\r\n",ev->Content_Type);}else if (S_ISREG(stat_buf.st_mode)) {ev->ret_code = 200;ev->length = sprintf(ev->buffer,"HTTP/1.1 200 OK\r\n""Content-Type: %s;charset=utf-8\r\n""Content-Length: %ld\r\n\r\n",ev->Content_Type, stat_buf.st_size);}}return ev->length;
}int send_cb(int fd, int events, void *arg) {struct ntyreactor *reactor = (struct ntyreactor *) arg;struct ntyevent *ev = ntyreactor_find_event_idx(reactor, fd);http_response(ev);printf("[socket fd=%d count=%d]\n%s", fd, ev->length, ev->buffer);int res_head_len = send(fd, ev->buffer, ev->length, 0);if (res_head_len > 0) {if (ev->ret_code == 200) {int filefd = open(ev->resource, O_RDONLY);struct stat stat_buf;fstat(filefd, &stat_buf);off_t offset = 0;while (offset != stat_buf.st_size) {int n = sendfile(fd, filefd, &offset, (stat_buf.st_size - offset));if (n == -1 && errno == EAGAIN) {usleep(5000);continue;}}printf("[resource: %s count:%ld]\r\n", ev->resource, offset);close(filefd);}nty_event_del(reactor->epfd, ev);nty_event_set(ev, fd, recv_cb, reactor);nty_event_add(reactor->epfd, EPOLLIN, ev);}else {nty_event_del(reactor->epfd, ev);close(ev->fd);}return 0;
}int accept_cb(int fd, int events, void *arg) {//非阻塞struct ntyreactor *reactor = (struct ntyreactor *) arg;if (reactor == NULL) return -1;struct sockaddr_in client_addr;socklen_t len = sizeof(client_addr);int clientfd;if ((clientfd = accept(fd, (struct sockaddr *) &client_addr, &len)) == -1) {printf("accept: %s\n", strerror(errno));return -1;}if ((fcntl(clientfd, F_SETFL, O_NONBLOCK)) < 0) {printf("%s: fcntl nonblocking failed, %d\n", __func__, MAX_EPOLL_EVENTS);return -1;}struct ntyevent *event = ntyreactor_find_event_idx(reactor, clientfd);nty_event_set(event, clientfd, recv_cb, reactor);nty_event_add(reactor->epfd, EPOLLIN, event);printf("new connect [%s:%d], pos[%d]\n",inet_ntoa(client_addr.sin_addr), ntohs(client_addr.sin_port), clientfd);return 0;
}int init_sock(short port) {int fd = socket(AF_INET, SOCK_STREAM, 0);fcntl(fd, F_SETFL, O_NONBLOCK);struct sockaddr_in server_addr;memset(&server_addr, 0, sizeof(server_addr));server_addr.sin_family = AF_INET;server_addr.sin_addr.s_addr = htonl(INADDR_ANY);server_addr.sin_port = htons(port);bind(fd, (struct sockaddr *) &server_addr, sizeof(server_addr));if (listen(fd, 20) < 0) {printf("listen failed : %s\n", strerror(errno));}return fd;
}int ntyreactor_alloc(struct ntyreactor *reactor) {if (reactor == NULL) return -1;if (reactor->evblk == NULL) return -1;struct eventblock *blk = reactor->evblk;while (blk->next != NULL) {blk = blk->next;}struct ntyevent *evs = (struct ntyevent *) malloc((MAX_EPOLL_EVENTS) * sizeof(struct ntyevent));if (evs == NULL) {printf("ntyreactor_alloc ntyevents failed\n");return -2;}memset(evs, 0, (MAX_EPOLL_EVENTS) * sizeof(struct ntyevent));struct eventblock *block = (struct eventblock *) malloc(sizeof(struct eventblock));if (block == NULL) {printf("ntyreactor_alloc eventblock failed\n");return -2;}memset(block, 0, sizeof(struct eventblock));block->events = evs;block->next = NULL;blk->next = block;reactor->blkcnt++; //return 0;
}struct ntyevent *ntyreactor_find_event_idx(struct ntyreactor *reactor, int sockfd) {int blkidx = sockfd / MAX_EPOLL_EVENTS;while (blkidx >= reactor->blkcnt) {ntyreactor_alloc(reactor);}int i = 0;struct eventblock *blk = reactor->evblk;while (i++ < blkidx && blk != NULL) {blk = blk->next;}return &blk->events[sockfd % MAX_EPOLL_EVENTS];
}int ntyreactor_init(struct ntyreactor *reactor) {if (reactor == NULL) return -1;memset(reactor, 0, sizeof(struct ntyreactor));reactor->epfd = epoll_create(1);if (reactor->epfd <= 0) {printf("create epfd in %s err %s\n", __func__, strerror(errno));return -2;}struct ntyevent *evs = (struct ntyevent *) malloc((MAX_EPOLL_EVENTS) * sizeof(struct ntyevent));if (evs == NULL) {printf("ntyreactor_alloc ntyevents failed\n");return -2;}memset(evs, 0, (MAX_EPOLL_EVENTS) * sizeof(struct ntyevent));struct eventblock *block = (struct eventblock *) malloc(sizeof(struct eventblock));if (block == NULL) {printf("ntyreactor_alloc eventblock failed\n");return -2;}memset(block, 0, sizeof(struct eventblock));block->events = evs;block->next = NULL;reactor->evblk = block;reactor->blkcnt = 1;return 0;
}int ntyreactor_destory(struct ntyreactor *reactor) {close(reactor->epfd);//free(reactor->events);struct eventblock *blk = reactor->evblk;struct eventblock *blk_next = NULL;while (blk != NULL) {blk_next = blk->next;free(blk->events);free(blk);blk = blk_next;}return 0;
}int ntyreactor_addlistener(struct ntyreactor *reactor, int sockfd, NCALLBACK acceptor) {if (reactor == NULL) return -1;if (reactor->evblk == NULL) return -1;struct ntyevent *event = ntyreactor_find_event_idx(reactor, sockfd);nty_event_set(event, sockfd, acceptor, reactor);nty_event_add(reactor->epfd, EPOLLIN, event);return 0;
}int ntyreactor_run(struct ntyreactor *reactor) {if (reactor == NULL) return -1;if (reactor->epfd < 0) return -1;if (reactor->evblk == NULL) return -1;struct epoll_event events[MAX_EPOLL_EVENTS + 1];int i;while (1) {int nready = epoll_wait(reactor->epfd, events, MAX_EPOLL_EVENTS, 1000);if (nready < 0) {printf("epoll_wait error, exit\n");continue;}for (i = 0; i < nready; i++) {struct ntyevent *ev = (struct ntyevent *) events[i].data.ptr;if ((events[i].events & EPOLLIN) && (ev->events & EPOLLIN)) {ev->callback(ev->fd, events[i].events, ev->arg);}if ((events[i].events & EPOLLOUT) && (ev->events & EPOLLOUT)) {ev->callback(ev->fd, events[i].events, ev->arg);}}}return 0;
}int main(int argc, char *argv[]) {unsigned short port = SERVER_PORT;if (argc == 2) {port = atoi(argv[1]);}struct ntyreactor *reactor = (struct ntyreactor *) malloc(sizeof(struct ntyreactor));ntyreactor_init(reactor);int i;int sockfds[PORT_COUNT] = {0};for (i = 0; i < PORT_COUNT; i++) {sockfds[i] = init_sock(port + i);ntyreactor_addlistener(reactor, sockfds[i], accept_cb);}ntyreactor_run(reactor);ntyreactor_destory(reactor);for (i = 0; i < PORT_COUNT; i++) {close(sockfds[i]);}free(reactor);return 0;
}