通过TCP/IP套接字发送文件（web服务器）
我正在编写一个web服务器的基本框架，但我不明白为什么我的文件不能通过我的套接字发送，我正在连接到它，它只是不发送我的文件。。。我错过了什么 //代码服务器.c //文件index.html*同一目录通过TCP/IP套接字发送文件（web服务器）,c,sockets,http,C,Sockets,Http,我正在编写一个web服务器的基本框架，但我不明白为什么我的文件不能通过我的套接字发送，我正在连接到它，它只是不发送我的文件。。。我错过了什么 //代码服务器.c //文件index.html*同一目录 <html> <body> <h1>Hello World</h1> </body> </html> 除了数学家1975年指出的在不同地方使用的错误大小之外，您真正的问题是您试图与需要HTTP服务器的浏览器通信 超文
<html>
<body>
<h1>Hello World</h1>
</body>
</html>
除了数学家1975年指出的在不同地方使用的错误大小之外，您真正的问题是您试图与需要HTTP服务器的浏览器通信 超文本传输协议是。它比简单的连接和内容转储更复杂 您必须根据请求解析请求，并以某种方式发送标题和内容。检查绑定是否失败，如果失败，请报告。您正在绑定到端口80；在类Unix操作系统下，只有root用户可以绑定到小于1024的保留端口 更新1： 在调用accept之前，必须将addrlen初始化为sizeofaddress。发件人： addrlen参数是一个值结果参数：调用方必须 初始化它以包含指向的结构的大小（以字节为单位） 地址为：；返回时，它将包含对等的实际大小 地址 为什么fsize+1？你不需要+1 未选中的返回值。第二个参数应该是fsize。目前，您只传递指针的大小
//create/bind socket
if ((create_socket = socket(AF_INET, SOCK_STREAM, 0)) > 0)
{
printf("The socket was created\n");
}
if (bind(create_socket, (struct sockaddr *) &address, sizeof(address)) == 0)
{
printf("Binding Socket\n");
//listen, create new_sock, write headers, send file
while (1){
if (listen(create_socket, 10) < 0) {
perror("server: listen");
exit(1);
}
int count = recv(new_socket, buffer, bufsize, 0);
printf("%.*s\n", count, buffer);
write(new_sock, "HTTP/1.1 200 OK\n", 16);
write(new_sock, "Content-length: 46\n", 19);
write(new_sock, "Content-Type: text/html\n\n", 25);
int count;
while ((count = read(in, buffer, sizeof buffer)) > 0)
{
send(out, buffer, count, 0);
}
if (count < 0)
{
perror("send failed");
}
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
bool writeDataToClient(int sckt, const void *data, int datalen)
{
const char *pdata = (const char*) data;
while (datalen > 0){
int numSent = send(sckt, pdata, datalen, 0);
if (numSent <= 0){
if (numSent == 0){
printf("The client was not written to: disconnected\n");
} else {
perror("The client was not written to");
}
return false;
}
pdata += numSent;
datalen -= numSent;
}
return true;
}
bool writeStrToClient(int sckt, const char *str)
{
return writeDataToClient(sckt, str, strlen(str));
}
int main(void){
int create_socket, new_socket;
char *buffer;
int bufsize = 1024;
struct sockaddr_in address;
socklen_t addrlen;
buffer = (char*) malloc(bufsize);
if (!buffer){
printf("The receive buffer was not allocated\n");
exit(1);
}
create_socket = socket(AF_INET, SOCK_STREAM, 0);
if (create_socket == -1){
perror("The socket was not created");
exit(1);
}
printf("The socket was created\n");
memset(&address, 0, sizeof(address));
address.sin_family = AF_INET;
address.sin_addr.s_addr = INADDR_ANY;
address.sin_port = htons(80);
if (bind(create_socket, (struct sockaddr *) &address, sizeof(address)) == -1){
perror("The socket was not bound");
exit(1);
}
printf("The socket is bound\n");
long fsize;
FILE *fp = fopen("index.html", "rb");
if (!fp){
perror("The file was not opened");
exit(1);
}
printf("The file was opened\n");
if (fseek(fp, 0, SEEK_END) == -1){
perror("The file was not seeked");
exit(1);
}
fsize = ftell(fp);
if (fsize == -1) {
perror("The file size was not retrieved");
exit(1);
}
rewind(fp);
char *msg = (char*) malloc(fsize);
if (!msg){
perror("The file buffer was not allocated\n");
exit(1);
}
if (fread(msg, fsize, 1, fp) != 1){
perror("The file was not read\n");
exit(1);
}
fclose(fp);
printf("The file size is %ld\n", fsize);
if (listen(create_socket, 10) == -1){
perror("The socket was not opened for listening");
exit(1);
}
printf("The socket is listening\n");
while (1) {
addrlen = sizeof(address);
new_socket = accept(create_socket, (struct sockaddr *) &address, &addrlen);
if (new_socket == -1) {
perror("A client was not accepted");
exit(1);
}
printf("A client is connected from %s:%hu...\n", inet_ntoa(address.sin_addr), ntohs(address.sin_port));
// I will leave it as an exercise for you to implement
// a proper HTTP request parser here...
int numRead = recv(new_socket, buffer, bufsize, 0);
if (numRead < 1){
if (numRead == 0){
printf("The client was not read from: disconnected\n");
} else {
perror("The client was not read from");
}
close(new_socket);
continue;
}
printf("%.*s\n", numRead, buffer);
if (!writeStrToClient(new_socket, "HTTP/1.1 200 OK\r\n")){
close(new_socket);
continue;
}
char clen[40];
sprintf(clen, "Content-length: %ld\r\n", fsize);
if (!writeStrToClient(new_socket, clen)){
close(new_socket);
continue;
}
if (!writeStrToClient(new_socket, "Content-Type: text/html\r\n")){
close(new_socket);
continue;
}
if (!writeStrToClient(new_socket, "Connection: close\r\n\r\n") == -1){
close(new_socket);
continue;
}
//if (!writeStrToClient(new_socket, "<html><body><H1>Hello world</H1></body></html>")){
if (!writeDataToClient(new_socket, msg, fsize)){
close(new_socket);
continue;
}
printf("The file was sent successfully\n");
close(new_socket);
}
close(create_socket);
return 0;
}
是的，这就是我认为是标题。。。。在发送fileindex.html之前，先在套接字上写这些文件行吗？@jordavis阅读了有关协议的内容。这个答案太长，无法表达，但网上有很多信息。我知道协议，我不是一个十足的白痴：，让服务器将html作为字符串发送，但现在我尝试将其作为文件发送时失败了。。我的猜测是，在发送包含html的缓冲区之前，我需要将标题发送到套接字。。。或者我需要在发送缓冲区之前将标题写入缓冲区？大图片，是的，标题在内容之前。但是，如果你真的打算认真对待这件事，那就多读一些关于protocol@JordanDavis：TCP是一种流式传输。您可以根据需要多次发送，数据将根据需要在网络层上进行缓冲。重要的是你发送的内容。我知道这不是因为我之前让它处理一个HTML字符串，而且编译器在bind上没有失败。我只是更新了我的代码，添加了值。。。为了清楚起见，我把支票留了下来，我把它写在这个问题的顶部……谢谢你输入@ejpt这个裸体服务器有很多问题，一点也不好笑。您没有很好地处理错误。您正在以文本模式而不是二进制模式打开文件。SizeOfMg是错误的，请使用fsize。我不建议将整个文件读入内存，而是将其分块读取并发送，否则以后将无法处理大型文件。你调用listen的次数太多了，只调用一次，而不是循环调用。您没有检查recv是否失败。。。。。。在发送回复之前，您根本没有试图解析客户机的正确性请求。您必须在回复标题中使用\r\n而不是\n。您的Content length标头未指定文件的实际fsize值不是46字节。您无法确保send成功发送所有请求的字节。发送fsize+1字节是错误的，因为该文件只有fsize字节数。并且没有连接：正在发送关闭标头。@Jordandavi不，您没有。您刚刚添加了成功报告。在这段代码中几乎没有任何故障处理。@jordavis：显然，他没有。代码完全错了，原因有十几个。@jordavis：我刚刚发了一个examp
但是你忽略了fread的返回值，如果read返回零，你就调用perror，这是无效的。我没有忽略fread的返回值，但是你说的recv的返回值是对的，我没有调用read。我已经修正了。我对代码做了一些调整。请重试编译。@Pilpel:在本例中不需要，因为它是硬编码的，只使用IPv4，只在INADR\U ANY上侦听。使用getaddrinfo将在中生成相同的sockaddr_，除非启用IPv6，在这种情况下，需要分配多个具有多个绑定的套接字，否则getaddrinfo是有意义的。或者您可以创建一个双堆栈套接字来同时处理IPv4和IPv6，在这种情况下，您将不再使用getaddrinfo。@Pilpel：它可以用于服务器端，但在客户端更有用
int count = recv(new_socket, buffer, bufsize, 0);
printf("%.*s\n", count, buffer);
write(new_sock, "HTTP/1.1 200 OK\n", 16);
write(new_sock, "Content-length: 46\n", 19);
write(new_sock, "Content-Type: text/html\n\n", 25);
if(send(new_sock, filebuff, fsize+1, 0) > 0){
printf("success");
}
else{
printf("failed");
}
int count;
while ((count = read(in, buffer, sizeof buffer)) > 0)
{
send(out, buffer, count, 0);
}
if (count < 0)
{
perror("send failed");
}
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
bool writeDataToClient(int sckt, const void *data, int datalen)
{
const char *pdata = (const char*) data;
while (datalen > 0){
int numSent = send(sckt, pdata, datalen, 0);
if (numSent <= 0){
if (numSent == 0){
printf("The client was not written to: disconnected\n");
} else {
perror("The client was not written to");
}
return false;
}
pdata += numSent;
datalen -= numSent;
}
return true;
}
bool writeStrToClient(int sckt, const char *str)
{
return writeDataToClient(sckt, str, strlen(str));
}
int main(void){
int create_socket, new_socket;
char *buffer;
int bufsize = 1024;
struct sockaddr_in address;
socklen_t addrlen;
buffer = (char*) malloc(bufsize);
if (!buffer){
printf("The receive buffer was not allocated\n");
exit(1);
}
create_socket = socket(AF_INET, SOCK_STREAM, 0);
if (create_socket == -1){
perror("The socket was not created");
exit(1);
}
printf("The socket was created\n");
memset(&address, 0, sizeof(address));
address.sin_family = AF_INET;
address.sin_addr.s_addr = INADDR_ANY;
address.sin_port = htons(80);
if (bind(create_socket, (struct sockaddr *) &address, sizeof(address)) == -1){
perror("The socket was not bound");
exit(1);
}
printf("The socket is bound\n");
long fsize;
FILE *fp = fopen("index.html", "rb");
if (!fp){
perror("The file was not opened");
exit(1);
}
printf("The file was opened\n");
if (fseek(fp, 0, SEEK_END) == -1){
perror("The file was not seeked");
exit(1);
}
fsize = ftell(fp);
if (fsize == -1) {
perror("The file size was not retrieved");
exit(1);
}
rewind(fp);
char *msg = (char*) malloc(fsize);
if (!msg){
perror("The file buffer was not allocated\n");
exit(1);
}
if (fread(msg, fsize, 1, fp) != 1){
perror("The file was not read\n");
exit(1);
}
fclose(fp);
printf("The file size is %ld\n", fsize);
if (listen(create_socket, 10) == -1){
perror("The socket was not opened for listening");
exit(1);
}
printf("The socket is listening\n");
while (1) {
addrlen = sizeof(address);
new_socket = accept(create_socket, (struct sockaddr *) &address, &addrlen);
if (new_socket == -1) {
perror("A client was not accepted");
exit(1);
}
printf("A client is connected from %s:%hu...\n", inet_ntoa(address.sin_addr), ntohs(address.sin_port));
// I will leave it as an exercise for you to implement
// a proper HTTP request parser here...
int numRead = recv(new_socket, buffer, bufsize, 0);
if (numRead < 1){
if (numRead == 0){
printf("The client was not read from: disconnected\n");
} else {
perror("The client was not read from");
}
close(new_socket);
continue;
}
printf("%.*s\n", numRead, buffer);
if (!writeStrToClient(new_socket, "HTTP/1.1 200 OK\r\n")){
close(new_socket);
continue;
}
char clen[40];
sprintf(clen, "Content-length: %ld\r\n", fsize);
if (!writeStrToClient(new_socket, clen)){
close(new_socket);
continue;
}
if (!writeStrToClient(new_socket, "Content-Type: text/html\r\n")){
close(new_socket);
continue;
}
if (!writeStrToClient(new_socket, "Connection: close\r\n\r\n") == -1){
close(new_socket);
continue;
}
//if (!writeStrToClient(new_socket, "<html><body><H1>Hello world</H1></body></html>")){
if (!writeDataToClient(new_socket, msg, fsize)){
close(new_socket);
continue;
}
printf("The file was sent successfully\n");
close(new_socket);
}
close(create_socket);
return 0;
}