IBM Presents OS/2 Software Hits 1995/OS-2_SW_HITS_2ND_EDITION_1995.ISO/i17/lwp42n.exe/UNIXLPR.C

C/C++ Source or Header | 1994-10-05 | 4KB | 222 lines

#include <stdio.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <errno.h>
#include <sys/stat.h>
#include <netdb.h>
#include <netinet/in.h>
/*
    A Sample LPR program for UNIX systems which currently don't support
the LPR protocol. Mainly for SYS V systems.

    This is an unsupported program.
*/



char    line[132];
int    pfd;
#ifdef BUFSIZ
#undef BUFSIZ
#endif
#define BUFSIZ 512
/*
 * Send a data file to the remote machine and spool it.
 * Return positive if we should try resending.
 */
sendfile( file)
    char *file;
{
    register int f, i, amt;
    struct stat stb;
    char buf[BUFSIZ];
    int sizerr, resp;

    if (stat(file, &stb) < 0 || (f = open(file, O_RDONLY)) < 0)
    {
        perror("hello");
        return(-1);
    }
    /*
     * Check to see if data file is a symbolic link. If so, it should
     * still point to the same file or someone is trying to print something
     * he shouldn't.
     */
    (void) sprintf(buf, "\3%ld %s\n",  stb.st_size, file);
    amt = strlen(buf);
    for (i = 0;  ; i++) {
        if (write(pfd, buf, amt) != amt ||
            (resp = response()) < 0 || resp == '\1') {
            (void) close(f);
            return(-2);
        } else if (resp == '\0')
            break;
        if (i == 0)
            printf("no space on remote; waiting for queue to drain");
        if (i == 10)
            printf("Can't send; queue full\n");
        sleep(5 * 60);
    }
    sizerr = 0;
    for (i = 0; i < stb.st_size; i += BUFSIZ) {
        amt = BUFSIZ;
        if (i + amt > stb.st_size)
            amt = stb.st_size - i;
        if (sizerr == 0 && read(f, buf, amt) != amt)
            sizerr = 1;
        if (write(pfd, buf, amt) != amt) {
            (void) close(f);
            return(-2);
        }
    }
    (void) close(f);
    if (sizerr) {
        printf("%s: changed size\n", file);
        /* tell recvjob to ignore this file */
        (void) write(pfd, "\1", 1);
        return(-1);
    }
    if (write(pfd, "\0", 1) != 1 || response())
        return(-2);
    return(0);
}
/*
 * Check to make sure there have been no errors and that both programs
 * are in sync with eachother.
 * Return non-zero if the connection was lost.
 */
response()
{
    char resp;

    if (read(pfd, &resp, 1) != 1) {
        fprintf(stderr,"Connection lost to queue\n");
        return(-1);
    }
    return(resp);
}
/*
 * Create a connection to the remote printer server.
 * Most of this code comes from rcmd.c.
 */
getport(rhost)
    char *rhost;
{
    struct hostent *hp;
    struct servent *sp;
    struct sockaddr_in sin;
    int s, timo = 1, lport = IPPORT_RESERVED - 1;
    int err;

    /*
     * Get the host address and port number to connect to.
     */
    hp = gethostbyname(rhost);
    if (hp == NULL)
    {
        fprintf(stderr,"unknown host %s\n", rhost);
        exit(1);
    }
    bzero((char *)&sin, sizeof(sin));
    bcopy(hp->h_addr, (caddr_t)&sin.sin_addr, hp->h_length);
    sin.sin_family = hp->h_addrtype;
    sin.sin_port = htons(515);

    /*
     * Try connecting to the server.
     */
retry:
    s = socket(AF_INET,SOCK_STREAM,0);
    if (s < 0)
        return(-1);

    if (connect(s, (caddr_t)&sin, sizeof(sin), 0) < 0) {
        err = errno;
        (void) close(s);
        errno = err;
        if (errno == EADDRINUSE) {
            lport--;
            goto retry;
        }
        if (errno == ECONNREFUSED && timo <= 16) {
            sleep(timo);
            timo *= 2;
            goto retry;
        }
        return(-1);
    }
    return(s);
}

/*
 * Acquire line printer or remote connection.
 */
openpr(RM,RP)
    char *RM,*RP;
{
    register int i, n;
    int resp;

    for (i = 1; ; i = i < 256 ? i << 1 : i) {
        resp = -1;
        pfd = getport(RM);
        if (pfd >= 0) {
            (void) sprintf(line, "\2%s\n", RP);
            n = strlen(line);
            if (write(pfd, line, n) == n &&
                (resp = response()) == '\0')
                break;
            (void) close(pfd);
        }
        if (i == 1) {
            if (resp < 0)
                printf("waiting for %s to come up\n", RM);
            else {
                printf("waiting for queue to be enabled on %s\n", RM);
                i = 256;
            }
        }
        sleep(i);
    }
}

main(argc,argv)
int argc;
char *argv[];
{
    int    i,resp;

    if ( argc != 5)
    {
        fprintf(stderr,"Usage: unixlpr host printer username file\n");
        exit(1);
    }
again:
    openpr(argv[1],argv[2]);
reprint:
    i=sendfile(argv[4]);
    switch(i)
    {
    case 0:
        sprintf(line,"\2%d cf\n",strlen(argv[3])+strlen(argv[1])+4);
        if (write(pfd, line, strlen(line)) != strlen(line) ||
            (resp = response()) < 0 || resp == '\1') {
            goto reprint;
        } else if (resp == '\0')
        {
            sprintf(line,"P%s\nf%s\n\0",argv[3],argv[1]);
            write(pfd,line,strlen(line)+1);
            resp = response();
        }
        close(pfd);
        exit(0);
    case -1:
        close(pfd);
        fprintf(stderr,"Error sending file.\n");
        exit(1);
    case -2:
        goto reprint;
    }
}