kshmain.c

linux内核调试小工具.可以读写指定地址上的数据

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <signal.h>
 
#ifdef WIN32
#include <winsock.h>
#define     WINSOCK_VERSION   MAKEWORD(2,0) 
#else
#include <linux/types.h>
#include <sys/select.h>
#include <sys/socket.h>
#include <linux/in.h>
#endif

#include "kshmain.h"

int inet_pton(int af, const char *src, void *dst);
static int inet_pton4(const char *src, u_char *dst);
#define EAFNOSUPPORT 47
#define INADDRSZ 4
#define KSH_SVR_PORT 7915

int still_loop = 1;
extern int errno;

int ksh_connect(char * ipaddr, int port)
{

    int socket_fd; 
    struct sockaddr_in sin;
    int error = 0;
#ifdef WIN32
    WSADATA wsaData;
    if(WSAStartup(WINSOCK_VERSION,&wsaData)) 
    {
        printf("Winsock init failed!");
        return -1;
    }    
#endif 
    sin.sin_family	     = AF_INET;
    sin.sin_addr.s_addr = inet_addr(ipaddr);
    sin.sin_port         = htons(KSH_SVR_PORT);

    /* Create the socket.  */ 
    socket_fd = socket (AF_INET, SOCK_STREAM, 0); 
    if(socket_fd <= 0){
        printf("create socket failed, socket_fd = %d\n", socket_fd);
        return -1;
    }
    /* Connect the socket.   */
    error = connect (socket_fd, (struct sockaddr*)&sin, sizeof(struct sockaddr_in)); 
    if(error){
        printf("connect failed, error = %d\n", error);
        return -1;
    }else{
        printf("connect ok\n");
    }
        
    return socket_fd;     
}

int main(int argc, char *argv[])
{
    char usr_input[MAX_CMD_LEN] = {0};
    fd_set fds, stdin_fd;
    int socket_fd = -1, max_fd;
    struct timeval timeout;
    int res, ipaddr;    
    char buffer[4050];
    
    if(argc != 2)
    {
        printf("usage  : ksh IP\n");
        printf("example: ksh 192.168.1.1\n");
        return -1;
    } 
    
    if(inet_pton(AF_INET, argv[1], &ipaddr) <= 0 ){
        printf("Invalid IP address!\n");
        return -1;
    }    
    FD_ZERO(&fds);
    FD_ZERO(&stdin_fd);
    socket_fd = ksh_connect(argv[1], KSH_SVR_PORT);
    if(socket_fd < 0){
        return -1;
    }
         
    printf("%s", CLI_PROMPT);
    
    while(still_loop)
    {
        FD_ZERO(&fds);
        FD_SET(socket_fd, &fds);
        FD_SET(0, &stdin_fd);
        
     	timeout.tv_sec = 0;
    	timeout.tv_usec = 0; 
              
    	/*linux和win下的select函数区别很大
         *win下的select只能用于socket fd
         *linux下的select能用于各种fd
         */
        res = select(max_fd+1, &fds, NULL, NULL, &timeout);
        if(res > 0){
            if(FD_ISSET(socket_fd, &fds)){
                /*read socket*/
                int len = recv(socket_fd, buffer, sizeof(buffer), 0);
                if(len > 0 && len < 4050){
                    buffer[len] = 0;
                    printf("%s\n", buffer);
                }else{
                    printf("something error happened, exit ksh\n");
                    break;
                }
                printf("%s", CLI_PROMPT);
            }
        }
        /*判断键盘是否有输入, 串口终端怎么办?*/
        if(kbhit()){
               int len = 0;
                usr_input[0] = '\0';
                fgets(usr_input, MAX_CMD_LEN-1, stdin);
                //printf("usr input:%s\n", usr_input);
                len = strlen(usr_input);
                usr_input[len-1] = 0;
                if( (len-1) > 0){
                    send(socket_fd, usr_input, len, 0);
                }else{                
                    printf("%s", CLI_PROMPT);             
                }
        }        
    }
    close(socket_fd);
#ifdef WIN32
    WSACleanup();
#endif    
    return 0;
}

/*********************************copy from inet_pton.c*********************************************/
/* int
 * inet_pton(af, src, dst)
 *	convert from presentation format (which usually means ASCII printable)
 *	to network format (which is usually some kind of binary format).
 * return:
 *	1 if the address was valid for the specified address family
 *	0 if the address wasn't valid (`dst' is untouched in this case)
 *	-1 if some other error occurred (`dst' is untouched in this case, too)
 * author:
 *	Paul Vixie, 1996.
 */
int
inet_pton(af, src, dst)
	int af;
	const char *src;
	void *dst;
{
	switch (af) {
	case AF_INET:
		return (inet_pton4(src, dst));
	/* I'm lazy, comment this
	case AF_INET6:
		return (inet_pton6(src, dst));
	*/
	default:
		errno = EAFNOSUPPORT;
		return (-1);
	}
	/* NOTREACHED */
}

/* int
 * inet_pton4(src, dst)
 *	like inet_aton() but without all the hexadecimal and shorthand.
 * return:
 *	1 if `src' is a valid dotted quad, else 0.
 * notice:
 *	does not touch `dst' unless it's returning 1.
 * author:
 *	Paul Vixie, 1996.
 */
static int
inet_pton4(src, dst)
	const char *src;
	u_char *dst;
{
	static const char digits[] = "0123456789";
	int saw_digit, octets, ch;
	u_char tmp[INADDRSZ], *tp;

	saw_digit = 0;
	octets = 0;
	*(tp = tmp) = 0;
	while ((ch = *src++) != '\0') {
		const char *pch;

		if ((pch = strchr(digits, ch)) != NULL) {
			u_int new = *tp * 10 + (pch - digits);

			if (new > 255)
				return (0);
			*tp = new;
			if (! saw_digit) {
				if (++octets > 4)
					return (0);
				saw_digit = 1;
			}
		} else if (ch == '.' && saw_digit) {
			if (octets == 4)
				return (0);
			*++tp = 0;
			saw_digit = 0;
		} else
			return (0);
	}
	if (octets < 4)
		return (0);

	memcpy(dst, tmp, INADDRSZ);
	return (1);
}
/*******************************copy end*****************************************/