#include "apue.h"#include "print.h"#include <ctype.h>#include <sys/select.h>#define MAXCFGLINE 512#define MAXKWLEN   16#define MAXFMTLEN  16/* * Get the address list for the given host and service and * return through ailistpp.  Returns 0 on success or an error * code on failure.  Note that we do not set errno if we * encounter an error. * * LOCKING: none. */intgetaddrlist(const char *host, const char *service,  struct addrinfo **ailistpp){	int				err;	struct addrinfo	hint;	hint.ai_flags = AI_CANONNAME;	hint.ai_family = AF_INET;	hint.ai_socktype = SOCK_STREAM;	hint.ai_protocol = 0;	hint.ai_addrlen = 0;	hint.ai_canonname = NULL;	hint.ai_addr = NULL;	hint.ai_next = NULL;	err = getaddrinfo(host, service, &hint, ailistpp);	return(err);}/* * Given a keyword, scan the configuration file for a match * and return the string value corresponding to the keyword. * * LOCKING: none. */static char *scan_configfile(char *keyword){	int				n, match;	FILE			*fp;	char			keybuf[MAXKWLEN], pattern[MAXFMTLEN];	char			line[MAXCFGLINE];	static char		valbuf[MAXCFGLINE];	if ((fp = fopen(CONFIG_FILE, "r")) == NULL)		log_sys("can't open %s", CONFIG_FILE);	sprintf(pattern, "%%%ds %%%ds", MAXKWLEN-1, MAXCFGLINE-1);	match = 0;	while (fgets(line, MAXCFGLINE, fp) != NULL) {		n = sscanf(line, pattern, keybuf, valbuf);		if (n == 2 && strcmp(keyword, keybuf) == 0) {			match = 1;			break;		}	}	fclose(fp);	if (match != 0)		return(valbuf);	else		return(NULL);}/* * Return the host name running the print server or NULL on error. * * LOCKING: none. */char *get_printserver(void){	return(scan_configfile("printserver"));}/* * Return the address of the network printer or NULL on error. * * LOCKING: none. */struct addrinfo *get_printaddr(void){	int				err;	char			*p;	struct addrinfo	*ailist;	if ((p = scan_configfile("printer")) != NULL) {		if ((err = getaddrlist(p, "ipp", &ailist)) != 0) {			log_msg("no address information for %s", p);			return(NULL);		}		return(ailist);	}	log_msg("no printer address specified");	return(NULL);}/* * "Timed" read - timout specifies the # of seconds to wait before * giving up (5th argument to select controls how long to wait for * data to be readable).  Returns # of bytes read or -1 on error. * * LOCKING: none. */ssize_ttread(int fd, void *buf, size_t nbytes, unsigned int timout){	int				nfds;	fd_set			readfds;	struct timeval	tv;	tv.tv_sec = timout;	tv.tv_usec = 0;	FD_ZERO(&readfds);	FD_SET(fd, &readfds);	nfds = select(fd+1, &readfds, NULL, NULL, &tv);	if (nfds <= 0) {		if (nfds == 0)			errno = ETIME;		return(-1);	}	return(read(fd, buf, nbytes));}/* * "Timed" read - timout specifies the number of seconds to wait * per read call before giving up, but read exactly nbytes bytes. * Returns number of bytes read or -1 on error. * * LOCKING: none. */ssize_ttreadn(int fd, void *buf, size_t nbytes, unsigned int timout){	size_t	nleft;	ssize_t	nread;	nleft = nbytes;	while (nleft > 0) {		if ((nread = tread(fd, buf, nleft, timout)) < 0) {			if (nleft == nbytes)				return(-1); /* error, return -1 */			else				break;      /* error, return amount read so far */		} else if (nread == 0) {			break;          /* EOF */		}		nleft -= nread;		buf += nread;	}	return(nbytes - nleft);      /* return >= 0 */}