BSD 4_3_Reno release

[unix-history] / usr / src / usr.sbin / lpr / lpc / lpc.c

/*
* Copyright (c) 1983 Regents of the University of California.
* All rights reserved.
*
* Redistribution and use in source and binary forms are permitted provided
* that: (1) source distributions retain this entire copyright notice and
* comment, and (2) distributions including binaries display the following
* acknowledgement:  ``This product includes software developed by the
* University of California, Berkeley and its contributors'' in the
* documentation or other materials provided with the distribution and in
* all advertising materials mentioning features or use of this software.
* Neither the name of the University nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
*/

#ifndef lint
char copyright[] =
"@(#) Copyright (c) 1983 Regents of the University of California.\n\
All rights reserved.\n";
#endif /* not lint */

#ifndef lint
static char sccsid[] = "@(#)lpc.c       5.10 (Berkeley) 6/1/90";
#endif /* not lint */

/*
* lpc -- line printer control program
*/
#include <stdio.h>
#include <signal.h>
#include <ctype.h>
#include <setjmp.h>
#include <syslog.h>

#include "lpc.h"

int     fromatty;

char    cmdline[200];
int     margc;
char    *margv[20];
int     top;
int     intr();
struct  cmd *getcmd();

jmp_buf toplevel;

main(argc, argv)
       char *argv[];
{
       register struct cmd *c;
       extern char *name;

       name = argv[0];
       openlog("lpd", 0, LOG_LPR);

       if (--argc > 0) {
               c = getcmd(*++argv);
               if (c == (struct cmd *)-1) {
                       printf("?Ambiguous command\n");
                       exit(1);
               }
               if (c == 0) {
                       printf("?Invalid command\n");
                       exit(1);
               }
               if (c->c_priv && getuid()) {
                       printf("?Privileged command\n");
                       exit(1);
               }
               (*c->c_handler)(argc, argv);
               exit(0);
       }
       fromatty = isatty(fileno(stdin));
       top = setjmp(toplevel) == 0;
       if (top)
               signal(SIGINT, intr);
       for (;;) {
               cmdscanner(top);
               top = 1;
       }
}

intr()
{
       if (!fromatty)
               exit(0);
       longjmp(toplevel, 1);
}

/*
* Command parser.
*/
cmdscanner(top)
       int top;
{
       register struct cmd *c;

       if (!top)
               putchar('\n');
       for (;;) {
               if (fromatty) {
                       printf("lpc> ");
                       fflush(stdout);
               }
               if (fgets(cmdline, sizeof(cmdline), stdin) == 0)
                       quit();
               if (cmdline[0] == 0 || cmdline[0] == '\n')
                       break;
               makeargv();
               c = getcmd(margv[0]);
               if (c == (struct cmd *)-1) {
                       printf("?Ambiguous command\n");
                       continue;
               }
               if (c == 0) {
                       printf("?Invalid command\n");
                       continue;
               }
               if (c->c_priv && getuid()) {
                       printf("?Privileged command\n");
                       continue;
               }
               (*c->c_handler)(margc, margv);
       }
       longjmp(toplevel, 0);
}

extern struct cmd cmdtab[];

struct cmd *
getcmd(name)
       register char *name;
{
       register char *p, *q;
       register struct cmd *c, *found;
       register int nmatches, longest;

       longest = 0;
       nmatches = 0;
       found = 0;
       for (c = cmdtab; p = c->c_name; c++) {
               for (q = name; *q == *p++; q++)
                       if (*q == 0)            /* exact match? */
                               return(c);
               if (!*q) {                      /* the name was a prefix */
                       if (q - name > longest) {
                               longest = q - name;
                               nmatches = 1;
                               found = c;
                       } else if (q - name == longest)
                               nmatches++;
               }
       }
       if (nmatches > 1)
               return((struct cmd *)-1);
       return(found);
}

/*
* Slice a string up into argc/argv.
*/
makeargv()
{
       register char *cp;
       register char **argp = margv;

       margc = 0;
       for (cp = cmdline; *cp;) {
               while (isspace(*cp))
                       cp++;
               if (*cp == '\0')
                       break;
               *argp++ = cp;
               margc += 1;
               while (*cp != '\0' && !isspace(*cp))
                       cp++;
               if (*cp == '\0')
                       break;
               *cp++ = '\0';
       }
       *argp++ = 0;
}

#define HELPINDENT (sizeof ("directory"))

/*
* Help command.
*/
help(argc, argv)
       int argc;
       char *argv[];
{
       register struct cmd *c;

       if (argc == 1) {
               register int i, j, w;
               int columns, width = 0, lines;
               extern int NCMDS;

               printf("Commands may be abbreviated.  Commands are:\n\n");
               for (c = cmdtab; c->c_name; c++) {
                       int len = strlen(c->c_name);

                       if (len > width)
                               width = len;
               }
               width = (width + 8) &~ 7;
               columns = 80 / width;
               if (columns == 0)
                       columns = 1;
               lines = (NCMDS + columns - 1) / columns;
               for (i = 0; i < lines; i++) {
                       for (j = 0; j < columns; j++) {
                               c = cmdtab + j * lines + i;
                               if (c->c_name)
                                       printf("%s", c->c_name);
                               if (c + lines >= &cmdtab[NCMDS]) {
                                       printf("\n");
                                       break;
                               }
                               w = strlen(c->c_name);
                               while (w < width) {
                                       w = (w + 8) &~ 7;
                                       putchar('\t');
                               }
                       }
               }
               return;
       }
       while (--argc > 0) {
               register char *arg;
               arg = *++argv;
               c = getcmd(arg);
               if (c == (struct cmd *)-1)
                       printf("?Ambiguous help command %s\n", arg);
               else if (c == (struct cmd *)0)
                       printf("?Invalid help command %s\n", arg);
               else
                       printf("%-*s\t%s\n", HELPINDENT,
                               c->c_name, c->c_help);
       }
}