我正在尝试使用MinGW（gcc file.c -o compiled.exe）在Windows中编译此.c代码：
/***************************************************/
/* AUTHOR : LAW CHIU YUEN */
/* FILENAME : smtpr.c */
/***************************************************/
#ifdef WIN32
#include <windows.h>
#include <winsock.h>
#else
#define closesocket close
#include <unistd.h>
#include <netdb.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <sys/socket.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <arpa/inet.h>
#include <ctype.h>
//#define MYPORT 40711 // the port users will be connecting to
#define PORT 25
#define MAXBUFLEN 1024 // max buffer size
#define RELAY_NAME 255 // max length of file name
#define BACKLOG 10 // how many pending connections queue will hold
#define MAXDATASIZE 512 // max number of bytes we can get at once
#define SQMAXDATASIZE 1048576 //1024 * 1024
#define RECVTIME 100 // max number of time to wait for client's message
#define MAXEMAILADDRESS 320 // 64 + 1 + 255
#define MAXRCPT 50 //max number of mail receipients
/* State1 */
#define ACCEPT 0
#define HELO 1
#define MAILFROM 2
#define RCPTTO 3
#define DATA 4
#define MESSAGE 5
#define QUIT 6
#define RELAY 7
/* State2 */
#define FIRSTHELO 0
#define SECONDHELO 1
#define MAXHELO 1024
/* tokenize mailto string, each time return the first email address */
/* eg. a@a.com,b@b.com,c@c.com --> a@a.com */
char* tokenize(char *mailto){
const char delimiters[] = ",";
char *token, *cp;
printf("b4 strtok: mailto:%s\n",mailto);
/* Make writable copy. */
token = strtok (mailto, delimiters); /* token => "words" */
printf("tokenize() speaking : mailto: %s\n",mailto);
printf("tokenize() speaking : token: %s\n",token);
return token;
}
/* tokenize mailto string, each time return the email address other then the first one*/
/* first call: a@a.com,b@b.com,c@c.com --> b@b.com */
/* second call: a@a.com,b@b.com,c@c.com --> c@c.com */
char* tokenize_null(){
const char delimiters[] = ",";
char *token, *cp;
token = strtok (NULL, delimiters); /* token => "words" */
printf("tokenize_null() speaking : token: %s\n",token);
return token;
}
/* take in an email_address, and header; */
/* convert to : header: email_address */
char* compose_mailheader(char *header,char *mail){
char *a = malloc(strlen(mail)+30);
char *b = NULL;
char *c = NULL;
strcpy(a, header);
b = strcat(a, mail);
c = strcat(b, "\r\n");
printf("compose_mailheader: b=%s\n", b);
return b;
}
/* 1. receive message from smtp server */
void receive(int fd, char* command, char *buf){
int numbytes;
if ((numbytes=recv(fd, buf, MAXDATASIZE, 0)) == -1) {
fprintf(stderr,"error in receiving\n");
exit(1);
}
buf[numbytes] = '\0';
printf(" receive() Received buf : %s",buf);
if ( strstr(buf, command) != NULL ){
printf(" receive() Received command : %s\n",command);
}else{
}
}
/* helo */
/* 1. called by relaymail() */
/* 2. interact with a smtp server */
void helo(int sockfd){
int numbytes;
char buf2[MAXDATASIZE];
char buf[MAXDATASIZE];
printf("\n");
printf("helo is called\n");
/*receive 220*/
receive(sockfd, "220 ", buf);
/* send helo */
if (send(sockfd, "HELO server\r\n", 13, 0) == -1)
perror("HELO SERVER");
// printf("sent HELO SERVER\n");
/* receive 250*/
receive(sockfd, "250 ", buf);
/* testing */
// if (send(sockfd, "HELO server\r\n", 13, 0) == -1)
// perror("HELO SERVER");
// receive(sockfd, "250 ", buf);
}
/* mailfrom */
/* 1. called by relaymail() */
/* 2. interact with a smtp server */
void mailfrom(int sockfd,char *mail_from){
char buf[MAXDATASIZE] = "MAIL FROM:";
char *out;
int numbytes;
int i;
printf("\n");
printf("mailfrom is called\n");
/* compose the "MAIL FROM:email@address.com" message */
strcat(buf, mail_from);
strcat(buf, "\r\n");
printf("mailfrom() speaking: buf=%s\n", buf);
printf("mailfrom() speaking: strlen(buf)=%i\n", strlen(buf));
/* send out */
if( send(sockfd, buf, strlen(buf), 0) == -1 )
perror("mailfrom()");
/* receive 250*/
receive(sockfd, "250 ", buf);
} //mailfrom
/* 1. called by rcptto() */
/* 2. interact with a smtp server */
void rcptto2(int sockfd,char *mailtos){
char buf[MAXDATASIZE]="";
char *a;
char *out;
int numbytes;
int i,len;
printf("\n");
printf("rcptto2 is called\n");
/* compose the "RCPT TO:email@address.com" message */
strcat(buf, "RCPT TO:");
strcat(buf, tokenize_null());
strcat(buf, "\r\n");
printf("rcptto2() speaking: buf=%s\n", buf);
printf("rcptto2() speaking: strlen(buf)=%i\n", strlen(buf));
/* send out */
if( send(sockfd, buf, strlen(buf), 0) == -1 )
perror("rcptto()");
/* receive 250*/
receive(sockfd, "250 ", buf);
/* clear the buffer */
for(i=0; i<strlen(buf);i++){
buf[i]='\0';
}//for()
}
/* rcptto */
/* 1. called by relaymail() */
/* 2. interact with a smtp server */
void rcptto(int sockfd,char *mailtos, int mailto_num){
char buf[MAXDATASIZE] = "RCPT TO:";
char *a;
char *out;
int numbytes;
int i,len;
printf("\n");
printf("rcptto is called\n");
/* sending the first address... */
/* compose the "RCPT TO:email@address.com" message */
strcat(buf, tokenize(mailtos));
strcat(buf, "\r\n");
printf("rcptto() speaking: buf=%s\n", buf);
printf("rcptto() speaking: strlen(buf)=%i\n", strlen(buf));
/* send out */
if( send(sockfd, buf, strlen(buf), 0) == -1 )
perror("rcptto()");
/* receive 250*/
receive(sockfd, "250 ", buf);
/* clear the buffer */
/* handle multiple recipients case*/
for(i=0;i<mailto_num-1;i++)
rcptto2(sockfd, mailtos);
/* sending remaining addresses... */
} //rcptto
/* 1. called by relaymail() */
/* 2. interact with a smtp server */
void data(int sockfd){
char buf[MAXDATASIZE] = "";
printf("\n");
printf("data() is called\n");
/* send "DATA" */
if( send(sockfd, "DATA\r\n", 6, 0) == -1 )
perror("data()");
/* receive 354 */
receive(sockfd, "354 ", buf);
}
/* 1. called by relaymail() */
/* 2. interact with a smtp server */
void message(int sockfd, char *msg){
int times,i,j;
int remainder;
printf("\n");
char out[1025];
printf("message() is called\n");
times = strlen(msg) / MAXDATASIZE;
remainder = strlen(msg) - (times * MAXDATASIZE);
printf("remainder: %i\n", remainder);
printf("times: %i\n", times);
for (i=0;i< times;i++){
for (j=0;j< 1024;j++)
out[j]= msg[1024*i + j];
out[1024 +1] = '\0';
printf("sending msg: %i\n", i);
if( send(sockfd, out, 1025, 0) == -1 );
}
printf("end while: %i\n", i);
printf("out: %s\n", out);
for (j=0;j< remainder;j++)
out[j]= msg[1024*times + j];
out[remainder +1] = '\0';
if( send(sockfd, out, remainder+1, 0) == -1 )
perror("message");
printf("out: %s\n", out);
}
/* 1. called by relaymail() */
/* 2. interact with a smtp server */
void quit(int sockfd){
char buf[MAXDATASIZE] = "";
printf("\n");
printf("quit() is called\n");
/* send "QUIT" */
if( send(sockfd, "QUIT\r\n", 6, 0) == -1 )
perror("quit()");
/* receive 354 */
receive(sockfd, "250 ", buf);
}
/*relay mail to a email server*/
void relaymail(char *relay,char *mail_from, char *mailto, int mailto_num, char *msg){
int sockfd, numbytes;
char buf[MAXDATASIZE];
struct hostent *he;
struct sockaddr_in their_addr; // connector's address information
int state = 1;
int logswitch = 0;
int logwhile = 0;
if ((he=gethostbyname(relay)) == NULL) { // get the host info
fprintf(stderr,"gethostbyname fail\n");
exit(1);
}
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
fprintf(stderr,"fail to create socket\n");
exit(1);
}
their_addr.sin_family = AF_INET; // host byte order
their_addr.sin_port = htons(PORT); // short, network byte order
their_addr.sin_addr = *((struct in_addr *)he->h_addr);
memset(&(their_addr.sin_zero), '\0', 8); // zero the rest of the struct
if (connect(sockfd, (struct sockaddr *)&their_addr, sizeof(struct sockaddr)) == -1) {
fprintf(stderr,"connect fail\n");
exit(1);
}
while (state <7 && logwhile <10){ /* make sure the program won't run indefinitely */
logwhile++;
/* log */
// printf("\n");
// printf("logwhile = %i\n", logwhile);
// printf("state = %i\n", state);
// printf("\n");
switch (state){
case HELO :
helo(sockfd);
state++;
printf ("end of case HELO\n");
break;
case MAILFROM :
mailfrom(sockfd, mail_from);
state++;
printf ("relaymail(): end of case MAILFROM\n");
break;
case RCPTTO :
rcptto(sockfd, mailto, mailto_num);
state++;
printf ("relaymail(): end of case RCPTTO\n");
break;
case DATA :
data(sockfd);
state++;
printf ("relaymail(): end of case DATA\n");
break;
case MESSAGE :
message(sockfd, msg);
printf ("relaymail(): end of case MESSAGE\n");
state++;
printf ("relaymail(): end of case MESSAGE\n");
case QUIT :
quit(sockfd);
state++;
printf ("end of case QUIT\n");
closesocket(sockfd);
break;
default :
break;
}
} // while()
closesocket(sockfd);
}
/* remove < > */
char* remove_brackets(char* input)
{
int length;
int i, j;
char* output;
length = strlen(input);
output = (char*) malloc(length + 1);
j = 0;
/* copy character of input which in not equal to < or > to output */
for (i=0; i<length; i++)
if ((input[i]!='<') && (input[i]!='>'))
{
output[j] = input[i];
j++;
}
output[j] = '\0';
return output;
}
/* trim the space(s) before and after the string */
char* trim_space(char* input)
{
int i, j, length, is_ch, is_end, end_pos;
char *output;
/* trim the space(s) before the string */
length = strlen(input);
output = (char*) malloc (length+1);
is_ch = 0;
is_end = 0;
j = 0;
for(i=0; i<length; i++)
{
/* copy input characters to output */
if (is_ch==1 || !isspace(input[i]))
{
output[j] = input[i];
j++;
is_ch = 1;
}
}
output[j] = '\0';
/* trim the space(s) after the string */
length = strlen(output);
end_pos = length-1;
is_end = 0;
for (i=0; i<length; i++)
if (is_end==0 && isspace(output[i]))
{
is_end = 1;
end_pos = i;
}
else if (!isspace(output[i]))
is_end = 0;
output[end_pos] = '\0';
return output;
}
/* convert : MAIL FROM: a@a.com ---> a@a.com */
char *extractemail(const char *buf, const int i){
char * email = NULL;
char * tmp_email = NULL;
char * tmp_email2 = NULL;
char * tmp_email3 = NULL;
/* extract email address */
/* 1. remove MAIL FROM: */
email = malloc(strlen(buf));
strcpy(email,buf);
email += i;
printf("\n");
printf("email =%s\n", email);
printf("email length =%i\n", strlen(email));
printf("\n");
/* 2. trim head and trailing whitespace */
tmp_email = trim_space(email);
printf("trimmed email= %s\n", tmp_email);
/* 3. remove <> */
tmp_email2 = remove_brackets(tmp_email);
printf("remove<> email= %s\n", tmp_email2);
/* 4. trim again */
// tmp_email3 = trim_space("ellen@cs.com.hk");
// printf("\n");
// printf("extracted email= ~~~~~~%s~~~~~~\n", tmp_email3);
// printf("\n");
// printf("extracted email= ~~~~~~%s~~~~~~\n", tmp_email3);
return tmp_email2;
}
/* check if email address is a valid one */
int check_email_validity(const char *address) {
// check if email address is valid
// return 1 if valid
// return 0 if invalid
int number = 0;
const char *a, *host;
static char *special_characters = "()<>@,;:\\\"[]";
/* validate name */
for (a = address; *a; a++) {
if (*a == '\"' && (a == address || *(a - 1) == '.' || *(a - 1) ==
'\"')) {
while (*++a) {
if (*a == '\"') break;
if (*a == '\\' && (*++a == ' ')) continue;
if (*a <= ' ' || *a >= 127) return 0;
}
if (!*a++) return 0;
if (*a == '@') break;
if (*a != '.') return 0;
continue;
}
if (*a == '@') break;
if (*a <= ' ' || *a >= 127) return 0;
if (strchr(special_characters, *a)) return 0;
}
if (a == address || *(a - 1) == '.') return 0;
/* next we validate the host portion (name@host) */
if (!*(host = ++a)) return 0;
do {
if (*a == '.') {
if (a == host || *(a - 1) == '.') return 0;
number++;
}
if (*a <= ' ' || *a >= 127) return 0;
if (strchr(special_characters, *a)) return 0;
} while (*++a);
return (number >= 1);
}
int main(int argc, char *argv[])
{
int sockfd, new_fd; // listen on sock_fd, new connection on new_fd
struct sockaddr_in my_addr; // my address information
struct sockaddr_in their_addr; // connector's address information
int sin_size;
int yes=1;
socklen_t addr_len;
int numbytes=0;
char buf[MAXBUFLEN] = "";
char tmp_msg[MAXBUFLEN] ="";
char message[SQMAXDATASIZE];
char message_buf[10000];
char *msg = message;
char quit[MAXBUFLEN];
int MYPORT;
char relay[RELAY_NAME];
int i,j;
char *email = NULL;
char *email2 = NULL;
char *mail_from = NULL;
char *mail_to = NULL;
char *tmp_mail = NULL;
char mailtos[2000];
int mailto_num =0;
char *data = NULL;
char *data2 = NULL;
char *quit1 = NULL;
char *quit2 = NULL;
int state1 = 0; //
int state2 = 0; // keep track of number of 'helo's
int logwhile = 0;
char hardcode_email[15] = "cylaw@cs.hku.hk";
#ifdef WIN32
WSADATA wsaData;
WSAStartup(0x0101, &wsaData);
#endif
/* check number of parameters */
if ( argc != 3 && argc !=2 ) {
fprintf(stderr,"usage: smtpr <port number> (<relay server>)\n");
exit(1);
}
/* fill in port number */
MYPORT = atoi(argv[1]);
if ( MYPORT <= 0){
fprintf(stderr, "Invalid port number.\nusage: smtpr <port number> (<relay server>)\n");
exit(1);
}
/* fill in the server relay to */
if (argc == 2) strcpy(relay, "some.mail.server");
else if (argc == 3) strcpy(relay, argv[2]);
printf("relay to %s\n", relay);
/*create a TCP socket */
if ((sockfd = socket(AF_INET, SOCK_STREAM, 0)) == -1) {
perror("socket");
exit(1);
}
printf("port number : %i\n", MYPORT);
my_addr.sin_family = AF_INET; // host byte order
my_addr.sin_port = htons(MYPORT); // short, network byte order
my_addr.sin_addr.s_addr = htonl(INADDR_ANY); // automatically fill with my IP
memset(&(my_addr.sin_zero), '\0', 8); // zero the rest of the struct
/* bind to the port number*/
if (bind(sockfd, (struct sockaddr *)&my_addr, sizeof(struct sockaddr)) == -1) {
perror("bind");
exit(1);
}
/* listen*/
if (listen(sockfd, BACKLOG) == -1) {
perror("listen");
exit(1);
}
/* slow the receiving speed */
// sleep(1);
while(1){
logwhile++;
switch ( state1 ){
case ACCEPT:
/* accept */
sin_size = sizeof(struct sockaddr_in);
if ((new_fd = accept(sockfd, (struct sockaddr *)&their_addr, &sin_size)) == -1) {
perror("accept");
}
printf("server: got connection from %s\n",inet_ntoa(their_addr.sin_addr));
/* send msg : 220 */
if (send(new_fd, "220 cylaw's smtpr ready\r\n", 25, 0) == -1)
perror("send");
/*proceed to next state*/
printf("state1 = %i\n", state1);
state1++;
break;
case HELO:
if(state2 == 0){ //state2 keep track of if this is the first HELO
if ((numbytes=recv(new_fd, buf, MAXDATASIZE, 0)) == -1) {
perror("recv");
exit(1);
}
}
buf[numbytes] = '\0';
/* log */
printf("case HELO\n");
printf("============\n");
printf("buf :%s\n", buf);
/* check on length */
if ( strlen(buf) < 6 || strlen(buf) > MAXDATASIZE ){
printf("550 Syntax: <HELO>\n");
if (send(new_fd, "550 Syntax: <HELO|EHLO> <hostname>\r\n", 36, 0) == -1)
perror("HELO send");
}
/* compare (case-insensitively) the first 4 bytes of buf with "HELO" and "EHLO" */
if ( (strncasecmp(buf, "HELO ", 5) != 0) && (strncasecmp(buf, "EHLO ", 5) != 0 ) ){
printf("550 Syntax: <HELO>\n");
if (send(new_fd, "550 Syntax: <HELO|EHLO> <hostname>\r\n", 36, 0) == -1)
perror("HELO-1 send");
}
/* not implement case : helo<space>aaaaa<space> */
if ( buf[5] == '\0' && buf[5] == ' ' ){
printf("550 Syntax: <HELO|EHLO> <hostname>\n");
if (send(new_fd, "550 Syntax: <HELO|EHLO> <hostname>\r\n", 36, 0) == -1)
perror("HELO-2 send");
}
/* send 250 OK */
printf("250 HELO OK\n");
if ( send( new_fd, "250 HELO OK\r\n", 13, 0 ) == -1 )
perror("HELO-250-OK send");
printf("\n");
/*proceed to next state*/
state1++;
state2++;
break; //case HELO
case MAILFROM :
if ((numbytes=recv(new_fd, buf, MAXDATASIZE, 0)) == -1) {
perror("recv");
exit(1);
}
buf[numbytes] = '\0';
/* log */
printf("\n");
printf("case MAILFROM\n");
printf("=============\n");
printf("buf :%s\n", buf);
/* HELO */
if ( (strncasecmp(buf, "HELO ", 5) == 0) || (strncasecmp(buf, "EHLO ", 5) == 0 ) ){
printf("HELO received at case MAILFROM, go back to case HELO\n");
state1--;
break;
}
/* check "MAIL FROM:" */
if ( strncasecmp(buf, "MAIL FROM:", 10) != 0 ){
printf("550 Syntax: MAIL FROM: <email-address>\n");
if (send(new_fd, "550 Syntax: MAIL FROM: <email-address>\r\n", 40, 0) == -1)
perror("MAIL FROM: send()");
exit(1);
}
/* extract email address */
mail_from = extractemail(buf, 10);
/* check email validity */
if ( check_email_validity(mail_from) == 0 ){ //0 - invalid 1 - valid
printf("550 Invalid email address\r\n");
if (send(new_fd, "550 Invalid email address\r\n", 27, 0) == -1)
perror("Email address send()");
break; //case MAILFROM
}
/* send 250 OK */
printf("250 MAIL FROM OK\n");
if ( send( new_fd, "250 MAIL FROM OK\r\n", 18, 0 ) == -1 )
perror("MAILFROM-250-OK send()");
printf("\n");
state1++;
break; //case MAILFROM
case RCPTTO :
/* check if this is the first MAIL FROM: <> line */
if ( mailto_num == 0){
if ((numbytes=recv(new_fd, buf, MAXDATASIZE, 0)) == -1) {
perror("recv");
exit(1);
}
buf[numbytes] = '\0';
}
/* log */
printf("\n");
printf("case RCPTTO\n");
printf("=============\n");
printf("state1 = %i\n", state1);
printf("buf :%s\n", buf);
/* check RCPT TO: <...> */
if ( strncasecmp(buf, "RCPT TO:", 8) != 0 ){
printf("550 Syntax: RCPT TO: <email-address>\n");
if (send(new_fd, "550 Syntax: RCPT TO: <email-address>\r\n", 38, 0) == -1)
perror("MAIL FROM: send()");
}
/* extract email address */
mail_to = extractemail(buf, 8); // 8 = strlen("RPCT TO:")
/* recipients address on to mailtos []*/
strcat(mailtos, mail_to);
strcat(mailtos, ",");
mailto_num++;
printf("mailtos %s\n", mailtos);
printf("mailto_num %i\n", mailto_num);
/* check email validity */
if ( check_email_validity(mail_to) == 0 ){
printf("550 Invalid email address\n");
if (send(new_fd, "550 Invalid email address\r\n", 27, 0) == -1)
perror("RCPTTO address send()");
break; //case MAILFROM
}
/* send 250 OK */
printf("250 RCPT TO OK\n");
if ( send( new_fd, "250 RCPT TO OK\r\n", 16, 0 ) == -1 )
perror("MAILFROM-250-OK send()");
state1++;
break; // case RCPTTO
case DATA :
if ((numbytes=recv(new_fd, buf, MAXDATASIZE, 0)) == -1) {
perror("recv");
exit(1);
}
buf[numbytes] = '\0';
/* log */
printf("\n");
printf("case DATA\n");
printf("=============\n");
printf("state1 = %i\n", state1);
printf("buf :%s\n", buf);
/* multiple recipients */
if ( strncasecmp(buf, "RCPT TO:", 8 ) == 0){
printf("Multiple recipients -- Go back to state RCPT TO\n");
printf("\n");
state1--;
break;
}
if ( strncasecmp(buf,"DATA", 4) != 0 ){
printf("451 Syntax: DATA\n");
if (send(new_fd, "451 Syntax: DATA\r\n", 18, 0) == -1)
perror("DATA send");
} else{
/* send 354 OK */
// send( new_fd, "354 End\r\n", 10, 0 );
printf("354 End data with <CR><LF>.<CR><LF>\n");
if ( send( new_fd, "354 End data with <CR><LF>.<CR><LF>\r\n", 37, 0 ) == -1 ){
perror("MAILFROM-354-OK send()");
printf("354 error\n");
exit(1);
}
printf("\n");
}
state1++;
break; // case DATA
case MESSAGE :
printf("\n");
printf("case MESSAGE\n");
printf("============\n");
i=0;
while(i<10000){
i++;
if ((numbytes=recv(new_fd, message_buf, 9999, 0)) == -1) {
perror("recv");
exit(1);
}
message_buf[numbytes] = '\0';
/* log */
// printf("message_buf:\n\n%s", message_buf);
/* append message_buf to message */
strcat(message, message_buf);
if (strstr (message_buf, "\r\n.\r\n") != NULL ){
/* send 250 OK */
printf(". found\n");
if ( send( new_fd, "250 message received\r\n", 22, 0 ) == -1 )
perror("MESSAGE");
printf("message:\n\n %s\n", message);
state1++;
break;
}//if()
}//while()
state1++;
break;
case QUIT :
if ((numbytes=recv(new_fd, quit, MAXDATASIZE, 0)) == -1) {
perror("recv");
exit(1);
}
quit[numbytes] = '\0';
/* log */
printf("\n");
printf("case QUIT\n");
printf("=============\n");
printf("buf :%s\n", quit);
printf("\n");
/* trim space " QUIT " */
// quit1 = malloc(strlen(quit));
// strcpy(quit1, quit);
// printf("quit :%s\n", quit1);
// quit2 = trim_space(quit1);
// printf("quit :%s\n", quit1);
/* check QUIT */
if ( strncasecmp(quit, "QUIT", 4) != 0 ){
state1 = QUIT;
if (send(new_fd, "550 Syntax: QUIT\r\n", 18, 0) == -1)
perror("QUIT");
}else{
/* send 221 OK */
if ( send( new_fd, "221 QUIT.\r\n", 11, 0 ) == -1 )
perror("QUIT");
printf("QUIT!\n");
closesocket(new_fd);
state1++;
break;
}
break; // case QUIT
case RELAY :
relaymail(relay,mail_from,mailtos,mailto_num, msg);
/* go back to ACCEPT states */
state1 = ACCEPT;
/* reset variables */
strcpy(buf, "");
strcpy(tmp_msg, "");
strcpy(message, "");
strcpy(message_buf, "");
strcpy(quit,"");
i=0;j=0;
email = NULL;
email2 = NULL;
mail_from = NULL;
mail_to = NULL;
tmp_mail = NULL;
strcpy(mailtos, "");
mailto_num =0;
data = NULL;
data2 = NULL;
quit1 = NULL;
quit2 = NULL;
state2 = 0;
break;
default : break;
}//switch
} // while(1)
close(new_fd);
#ifdef WIN32
WSACleanup();
#endif
return 0;
}
但它失败了，错误：
C:\MinGW\bin>gcc file.c -o compiled.exe
file.c: In function `main':
file.c:973: error: `socklen_t' undeclared (first use in this function)
file.c:973: error: (Each undeclared identifier is reported only once
file.c:973: error: for each function it appears in.)
file.c:973: error: syntax error before "addr_len"
我尝试使用谷歌搜索错误但我发现的只是有关编译特定软件的信息，而不是可能导致它的原因。
我该怎么做才能解决此错误？
答案 0 :(得分：26)
在mingw下你可以尝试包含ws2tcpip.h
#include <ws2tcpip.h>
答案 1 :(得分：8)
找出它所定义的.h文件，并包含它。在Unix / Linux机器上，我将从/ usr / include
中的find / grep开始$ find /usr/include -name \*.h -print0 |xargs -0 grep -w socklen_t
...
/usr/include/unistd.h:typedef __socklen_t socklen_t;
...
/usr/include/sys/socket.h: socklen_t *__restrict __addr_len);
看起来它是在unistd.h中定义的 - 但是你已经包含了那个，所以我猜你在那边被覆盖了。我不知道你如何找到要包含在Windows端的文件。
答案 2 :(得分：3)
检查socket.h - 最有可能定义的位置。由于socket.h包含（由于它包含cygwin/socket.h这一事实），您的代码可以很好地编译CygWin：
typedef int socklen_t;
作为kludge，您可以尝试将该行添加到您自己的代码中。但你仍然应该调查为什么它缺失了，并且可能会提出错误报告。
有很多网页抱怨MinGW不支持socklen_t，例如here，here，here和here，其中最后一个说明了它如我在上面的kludge中定义的那样，我住在ws2tcpip.h。
答案 3 :(得分：2)
对于Windows，要获取socklen_t的定义：
#include <ws2tcpip.h>
自VS2017起有效。基于https://docs.microsoft.com/en-us/windows/win32/api/ws2tcpip/nf-ws2tcpip-getnameinfo。
我发现我需要将基于Linux的特定套接字源文件移植到Windows的另外两个标头是：
#include <winsock2.h>
#include <Ws2ipdef.h>
答案 4 :(得分：1)
根据Unix Specification，socket.h提供了一个类型socklen_t，它是一个长度至少为32位的无符号不透明整数类型。显然MingW不包括它。
您可以将其定义为：
#include <stdint.h>
typedef uint32_t socklen_t;