#ifndef _UTIL_H #define _UTIL_H /********************************************** * init - port is the number of the port you want the server to be started on - initializes the connection acception/handling system - YOU MUST CALL THIS EXACTLY ONCE (not once per thread, but exactly one time, in the main thread of your program) BEFORE USING ANY OF THE FUNCTIONS BELOW - if init encounters any errors, it will call exit(). ************************************************/ void init(int port); /********************************************** * accept_connection - takes no parameters - returns a file descriptor for further request processing. DO NOT use the file descriptor on your own -- use get_request() instead. - if the return value is negative, the request should be ignored. ***********************************************/ int accept_connection(void); /********************************************** * get_request - parameters: - fd is the file descriptor obtained by accept_connection() from where you wish to get a request - filename is the location of a character buffer in which this function should store the requested filename. (Buffer should be of size 1024 bytes.) - returns 0 on success, nonzero on failure. You must account for failures because some connections might send faulty requests. This is a recoverable error - you must not exit inside the thread that called get_request. After an error, you must NOT use a return_request or return_error function for that specific 'connection'. ************************************************/ int get_request(int fd, char *filename); /********************************************** * return_result - returns the contents of a file to the requesting client and cleans up the connection to the client - parameters: - fd is the file descriptor obtained by accept_connection() to where you wish to return the result of a request - content_type is a pointer to a string that indicates the type of content being returned. possible types include "text/html", "text/plain", "image/gif", "image/jpeg" cor- responding to .html, .txt, .gif, .jpg files. - buf is a pointer to a memory location where the requested file has been read into memory (the heap). return_result will use this memory location to return the result to the user. (remember to use -D_REENTRANT for CFLAGS.) you may safely deallocate the memory after the call to return_result (if it will not be cached). - numbytes is the number of bytes the file takes up in buf - returns 0 on success, nonzero on failure. ************************************************/ int return_result(int fd, char *content_type, char *buf, int numbytes); /********************************************** * return_error - returns an error message in response to a bad request and cleans up the connection to the client - parameters: - fd is the file descriptor obtained by accept_connection() to where you wish to return the error - buf is a pointer to the location of the error text - returns 0 on success, nonzero on failure. ************************************************/ int return_error(int fd, char *buf); #endif /* _UTIL_H */