/*-------------------------------------------------------------------------* *--- ---* *--- subPatServer.c ---* *--- ---* *--- This file defines a C program that gets file-sys commands ---* *--- from client via a socket, executes those commands in their own ---* *--- threads, and returns the corresponding output back to the ---* *--- client. ---* *--- ---* *--- ---- ---- ---- ---- ---- ---- ---- ---- ---* *--- ---* *--- Version 1a 2018 November 8 Joseph Phillips ---* *--- ---* *-------------------------------------------------------------------------*/ // Compile with: // $ gcc subPatServer.c -o subPatServer -lpthread //--- Header file inclusion ---// #include "subPat.h" #include // For pthread_create() //--- Definition of constants: ---// #define STD_OKAY_MSG "Okay" #define STD_ERROR_MSG "Error doing operation" #define STD_BYE_MSG "Good bye!" #define THIS_PROGRAM_NAME "subPatServer" #define OUTPUT_FILENAME "out.txt" #define ERROR_FILENAME "err.txt" const int ERROR_FD = -1; //--- Definition of global vars: ---// // PURPOSE: To be non-zero for as long as this program should run, or '0' // otherwise. //--- Definition of functions: ---// // YOUR CODE HERE // PURPOSE: To run the server by 'accept()'-ing client requests from // 'listenFd' and doing them. void doServer (int listenFd ) { // I. Application validity check: // II. Server clients: pthread_t threadId; pthread_attr_t threadAttr; int threadCount = 0; pthread_attr_init(&threadAttr); pthread_attr_setdetachstate(&threadAttr, PTHREAD_CREATE_DETACHED); while (1) {  // YOUR CODE HERE } pthread_attr_destroy(&threadAttr); // III. Finished: } // PURPOSE: To decide a port number, either from the command line arguments // 'argc' and 'argv[]', or by asking the user. Returns port number. int getPortNum (int argc, char* argv[] ) { // I. Application validity check: // II. Get listening socket: int portNum; if (argc >= 2) portNum = strtol(argv[1],NULL,0); else { char buffer[BUFFER_LEN]; printf("Port number to monopolize? "); fgets(buffer,BUFFER_LEN,stdin); portNum = strtol(buffer,NULL,0); } // III. Finished: return(portNum); } // PURPOSE: To attempt to create and return a file-descriptor for listening // to the OS telling this server when a client process has connect()-ed // to 'port'. Returns that file-descriptor, or 'ERROR_FD' on failure. int getServerFileDescriptor (int port ) { // I. Application validity check: // II. Attempt to get socket file descriptor and bind it to 'port': // II.A. Create a socket int socketDescriptor = socket(AF_INET, // AF_INET domain SOCK_STREAM, // Reliable TCP 0); if (socketDescriptor < 0) { perror(THIS_PROGRAM_NAME); return(ERROR_FD); } // II.B. Attempt to bind 'socketDescriptor' to 'port': // II.B.1. We'll fill in this datastruct struct sockaddr_in socketInfo; // II.B.2. Fill socketInfo with 0's memset(&socketInfo,'\0',sizeof(socketInfo)); // II.B.3. Use TCP/IP: socketInfo.sin_family = AF_INET; // II.B.4. Tell port in network endian with htons() socketInfo.sin_port = htons(port); // II.B.5. Allow machine to connect to this service socketInfo.sin_addr.s_addr = INADDR_ANY; // II.B.6. Try to bind socket with port and other specifications int status = bind(socketDescriptor, // from socket() (struct sockaddr*)&socketInfo, sizeof(socketInfo) ); if (status < 0) { perror(THIS_PROGRAM_NAME); return(ERROR_FD); } // II.B.6. Set OS queue length: listen(socketDescriptor,5); // III. Finished: return(socketDescriptor); } int main (int argc, char* argv[] ) { // I. Application validity check: // II. Do server: int port = getPortNum(argc,argv); int listenFd = getServerFileDescriptor(port); int status = EXIT_FAILURE; if (listenFd >= 0) { doServer(listenFd); close(listenFd); status = EXIT_SUCCESS; } // III. Finished: return(status); }