my.c

#include <stdlib.h>
#include <errno.h>
#include <sys/socket.h>
 #include <sys/types.h>



void perr_exit(const char *s)
{
	perror(s);
	exit(1);
}



//***************************網路*********************************
int Accept(int fd, struct sockaddr*  addr, socklen_t* addrlen)
 

{
        int n;
	again:
	if ( (n = accept(fd, addr, addrlen)) < 0)
	 {
		if ((errno == ECONNABORTED) || (errno == EINTR))
			goto again;
		else
			perr_exit("accept error");
	}
	return n;
} 




int Bind(int fd, const struct sockaddr *addr, socklen_t addrlen)
{
	int n;
	if ((n = bind(fd, addr, addrlen)
 
) < 0)
		perr_exit("bind error");
	return n;
}




int Connect(int fd, const struct sockaddr *addr, socklen_t addrlen)
{
	int n;
	if ((n = connect(fd, addr, addrlen)) < 0)
		perr_exit("connect error");
	return n;
}




int Listen(int fd, int backlog)
{
	int n;
	if ((n = listen(fd, backlog)) <
 
 0)
		perr_exit("listen error");
	return n;
}




int Socket(int family, int type, int protocol)
{
	int n;
	if ( (n = socket(family, type, protocol)) < 0)
		perr_exit("socket error");
	return n;
}





//***************************讀寫操作*********************************
ssize_t Read(int fd, void *ptr, size_t nbytes)
{
	ssize_t n;
  again:
	if ( (n = read(fd, ptr, nbytes)) == -1) 
	{
		if (errno == EINTR)
			goto again;
		else
			return -1;
	}
	return n;
}



ssize_t Write(int fd, const void *buf, size_t nbytes)
{
	ssize_t n;
  again:
	if ( (n = write(fd, buf, nbytes)) == -1)
	 {
		if (errno == EINTR)
			goto again;
		else
			return -1;
	 }
	return n;
}



//讀指定位元組數
ssize_t Readn(int fd, void *vptr, size_t n)
{
	size_t nleft;
	ssize_t nread;
	char *ptr;

	ptr = vptr;
	nleft = n;

	while (nleft > 0) 
	{
		if ( (nread = read(fd, ptr, nleft)) < 0) 
		{
			if (errno == EINTR)
				nread = 0;
			else
				return -1;
		} 
		else if (nread == 0)
			break;
			
		nleft -= nread;
		ptr += nread;
	}
	return n - nleft;
}




//寫指定的位元組數
ssize_t Writen(int fd, const void *vptr, size_t n)
{
	size_t nleft;
	ssize_t nwritten;
	const char *ptr;

	ptr = vptr;
	nleft = n;

	while (nleft > 0) 
       {
		if ( (nwritten = write(fd, ptr, nleft)) <= 0) 
		{
			if (nwritten < 0 && errno == EINTR)
				nwritten = 0;
			else
				return -1;
		}
		nleft -= nwritten;
		ptr += nwritten;
	}
	return n;
}



//讀100位元組，通過ptr返回1位元組，然後每次呼叫都返回    第一次讀到的資料的   一個位元組，直到100位元組全部返回
static ssize_t my_read(int fd, char *ptr)
{
	static int read_cnt;
	static char *read_ptr;
	static char read_buf[100];

	if (read_cnt <= 0) 
	{
        again:
		if ((read_cnt = read(fd, read_buf, sizeof(read_buf))) < 0)
		 {
			if (errno == EINTR)
				goto again;
			return -1;	
		 }
		  else if (read_cnt == 0)
			return 0;
		 read_ptr = read_buf;
        }
	read_cnt--;
	*ptr = *read_ptr++;
	return 1;
}




//讀一行
ssize_t Readline(int fd, void *vptr, size_t maxlen)
{
	ssize_t n, rc;
	char c, *ptr;
	ptr = vptr;

	for (n = 1; n < maxlen; n++) 
	{
		if ( (rc = my_read(fd, &c)) == 1) 
		{
			*ptr++ = c;
			if (c == '\n')
				break;
		} 
		else if (rc == 0) 
		{
			*ptr = 0;
			return n - 1;
		}
		 else
			return -1;
	}
	
	*ptr = 0;
	return n;
}

my.h

#ifndef __WRAP_H_
#define __WRAP_H_

//socket相關
void perr_exit(const char *s);
int Accept(int fd, struct sockaddr*  addr, socklen_t* addrlen);
int Bind(int fd, const struct sockaddr *addr, socklen_t addrlen);
int Connect(int fd, const struct sockaddr *addr, socklen_t addrlen);
int Listen(int fd, int backlog);
int Socket(int family, int type, int protocol);

//讀寫相關
ssize_t Read(int fd, void *ptr, size_t nbytes);
ssize_t Write(int fd, const void *buf, size_t nbytes);
ssize_t Readn(int fd, void *vptr, size_t n);
ssize_t Writen(int fd, const void *vptr, size_t n);
static ssize_t my_read(int fd, char *ptr);
ssize_t Readline(int fd, void *vptr, size_t maxlen);
#endif