linux下用c语言实现的一个ftp程序.zip

#include <sys/types.h> #include <sys/socket.h> #include <netinet/in.h> #include <netdb.h> #include <stdio.h> #include <unistd.h> #include <dirent.h> #include <string.h> #include <sys/stat.h> #include <fcntl.h> #define TRUE 1 #define LISTEN_PORT 3499 #define dataLen 1024 char currentDirPath[200]; char currentDirName[30]; char help[]="get get a file from server\n put upload a file to server\n pwd display the current directory of server\n dir display the files in the current directory of server\n cd change the directory of server\n ? display the whole command which equals 'help'\n quit return\n"; char *getDirName(char *dirPathName); void cmd_pwd(int sock); void cmd_dir(int sock); void cmd_cd(int sock,char *dirName); void cmd_cdback(int sock); void cmd_help(int sock); void cmd_get(int sock,char*fileName); void cmd_put(int sock,char *fileName); int main(int argc,char *argv[]) { int sock,sockmsg, length, lengthmsg; char client_cmd[10] , cmd_arg[20]; struct sockaddr_in server; struct sockaddr_in servermsg; int datasock, msgsock; pid_t child; // int datasock; //data socket int rval; sock=socket(AF_INET,SOCK_STREAM,0); sockmsg=socket(AF_INET,SOCK_STREAM,0); if (sock<0||sockmsg<0) { perror("opening stream socket"); exit(1); } server.sin_family=AF_INET; server.sin_addr.s_addr=INADDR_ANY; server.sin_port=htons(LISTEN_PORT); servermsg.sin_family=AF_INET; servermsg.sin_addr.s_addr=INADDR_ANY; servermsg.sin_port=htons(LISTEN_PORT+1); if (bind(sock,(struct sockaddr *)&server,sizeof server)<0||bind(sockmsg,(struct sockaddr *)&servermsg,sizeof servermsg)<0) { perror("binding stream socket"); exit(1); } length=sizeof server; lengthmsg=sizeof servermsg; if (getsockname(sock,(struct sockaddr *)&server,&length)<0||getsockname(sockmsg,(struct sockaddr *)&servermsg,&lengthmsg)<0) { perror("getting socket name"); exit(1); } printf("Socket port # %d %d\n",ntohs(server.sin_port),ntohs(servermsg.sin_port)); memset(currentDirPath,0,sizeof(currentDirPath)); getcwd(currentDirPath,sizeof(currentDirPath)); listen(sock,2); listen(sockmsg,2); do { datasock = accept(sock,(struct sockaddr*)0,(int*)0); msgsock = accept(sockmsg,(struct sockaddr*)0,(int*)0); if (datasock == -1||msgsock==-1) perror("accept"); else { if((child=fork())==-1) { printf("Fork Error!\n"); } //The child process if(child==0) { printf("connection accepted! new client comming\n"); loop: memset(client_cmd,0,sizeof(client_cmd)); rval=0; rval=read(msgsock,client_cmd,sizeof(client_cmd)); if(rval<0) { perror("reading command failed\n"); } else if(rval==0) { printf("connection closed.\n"); close(datasock); close(msgsock); } else { if(strcmp(client_cmd,"pwd")==0) { printf("cmmand pwd\n"); cmd_pwd(datasock); printf("done\n\n"); goto loop; } else if(strcmp(client_cmd,"dir")==0) { printf("command dir\n"); cmd_dir(datasock); printf("done\n\n"); goto loop; } else if(strcmp(client_cmd,"cd")==0) { printf("command cd\n"); //read the argument memset(cmd_arg,0,sizeof(cmd_arg)); read(msgsock,cmd_arg,sizeof(cmd_arg)); cmd_cd(datasock,cmd_arg); printf("done\n\n"); goto loop; } else if(strcmp(client_cmd,"cd..")==0) { printf("command cd..\n"); cmd_cdback(datasock); printf("done\n\n"); goto loop; } else if(strcmp(client_cmd,"get")==0) { printf("command get\n"); memset(cmd_arg,0,sizeof(cmd_arg)); read(msgsock,cmd_arg,sizeof(cmd_arg)); cmd_get(datasock,cmd_arg); printf("done\n\n"); goto loop; } else if(strcmp(client_cmd,"put")==0) { printf("command put\n"); memset(cmd_arg,0,sizeof(cmd_arg)); read(msgsock,cmd_arg,sizeof(cmd_arg)); cmd_put(datasock,cmd_arg); printf("done\n\n"); goto loop; } else if(strcmp(client_cmd,"?")==0) { printf("command ?\n"); cmd_help(datasock); printf("done\n\n"); goto loop; } else if(strcmp(client_cmd,"quit")==0) { printf("quit\n"); goto endchild; } else { printf("bad request!\n"); goto loop; } } endchild: printf("connection closed.\n"); close(datasock); close(msgsock); exit(); } } }while(TRUE); exit(0); } //pwd command void cmd_pwd(int sock) { int len; memset(currentDirPath,0,sizeof(currentDirPath)); getcwd(currentDirPath,sizeof(currentDirPath)); char *savePointer=getDirName(currentDirPath); strcpy(currentDirName,savePointer); len=strlen(currentDirName)+1; write(sock,currentDirName,len); } //dir command void cmd_dir(int sock) { DIR *pdir; char fileName[30]; char fileInfo[50]; int i, fcounts=0, len; struct dirent *pent; int fd; struct stat fileSta; char filePath[200]; pdir=opendir(currentDirPath); pent=readdir(pdir); while(pent!=NULL) { fcounts++; pent=readdir(pdir); } write(sock,&fcounts,sizeof(int)); closedir(pdir); if(fcounts<=0) { return; } else { pdir=opendir(currentDirPath); for(i=0;i<fcounts;i++) { pent=readdir(pdir); memset(fileName,0,30); memset(fileInfo,0,sizeof(fileInfo)); strcpy(fileName,pent->d_name); //check the file is a directory or a file memset(filePath,0,sizeof(filePath)); strcpy(filePath,currentDirPath); strcat(filePath,"/"); strcat(filePath,fileName); fd=open(filePath,O_RDONLY, S_IREAD); fstat(fd,&fileSta); if(S_ISDIR(fileSta.st_mode)) { strcat(fileInfo,"dir\t"); strcat(fileInfo,fileName); } else { strcat(fileInfo,"file\t"); strcat(fileInfo,fileName); } write(sock,fileInfo,sizeof(fileInfo)); } closedir(pdir); } } //command cd void cmd_cd(int sock,char *dirName) { DIR *pdir; struct dirent *pent; char filename[30]; int i,fcounts=0; int flag=0; pdir=opendir(currentDirPath); pent=readdir(pdir); while(pent!=NULL) { fcounts++; pent=readdir(pdir); } closedir(pdir); if(fcounts<=0) { return; } else { pdir=opendir(currentDirPath); for(i=0;i<fcounts;i++) { pent=readdir(pdir); if(strcmp(pent->d_name,dirName)==0) { strcat(currentDirPath,"/"); strcat(currentDirPath,dirName); flag=1; break; } } if(flag==1) { write(sock,currentDirPath,sizeof(currentDirPath)); } closedir(pdir); } } //command cd.. void cmd_cdback(int sock) { int len; int i, record; len=strlen(currentDirPath); for(i=len-1;i>=0;i--) { if(currentDirPath[i]=='/') { currentDirPath[i]='\0'; break; } currentDirPath[i]='\0'; } } //command ? void cmd_help(int sock) { int len=strlen(help)+1; write(sock,help,len); } //command get void cmd_get(int sock,char*fileName) { int fd; struct stat fileSta; long fileSize; char filePath[200], buf[dataLen]; memset(filePath,0,sizeof(filePath)); strcpy(filePath,currentDirPath); strcat(filePath,"/"); strcat(filePath,fileName); fd=open(filePath,O_RDONLY, S_IREAD); if(fd!=-1) { fstat(fd,&fileSta); fileSize=(long) fileSta.st_size; write(sock,&fileSize,sizeof(long)); memset(buf,0,dataLen); while(fileSize>dataLen) { read(fd,buf,dataLen); write(sock,buf,dataLen); fileSize=fileSize-dataLen; } read(fd,buf,fileSize); write(sock,buf,fileSize); close(fd); printf("transfer completed\n"); } else { printf("open file %s failed\n",filePath); } } //command put void cmd_put(int sock,char *fileName) { int fd; long fileSize; char filePath[200], buf[dataLen]; strcpy(filePath,currentDirPath); strcat(filePath,"/"); strcat(filePath,fileName); fd=open(filePath,O_RDWR|O_CREAT, S_IREAD|S_IWRITE); if(fd!=-1) { memset(buf,0,dataLen); read(sock,&fileSize,sizeof(long)); while(f