update from Rodney Ruddock (rodney@snowhite.cis.uoguelph.ca)

[unix-history] / usr / src / contrib / ed / filename.c

/*-
* Copyright (c) 1992 The Regents of the University of California.
* All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Rodney Ruddock of the University of Guelph.
*
* %sccs.include.redist.c%
*/

#ifndef lint
static char sccsid[] = "@(#)filename.c  5.7 (Berkeley) %G%";
#endif /* not lint */

#include <sys/types.h>

#include <limits.h>
#include <regex.h>
#include <setjmp.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#ifdef DBI
#include <db.h>
#endif

#include "ed.h" 
#include "extern.h"


/*
* A central function for any command that has to deal with a filename
* (to be or not to be remembered).
*/
char *
filename(inputt, errnum)
       FILE *inputt;
       int *errnum;
{
       register int l_cnt = 0;
       char *l_fname;
       int l_esc = 0, l_bang_flag = 0;

       l_fname = calloc(FILENAME_LEN+2, sizeof(char));
       if (l_fname == NULL) {
               *errnum = -1;
               strcpy(help_msg, "out of memory error");
               return (NULL);
       }
       if ((ss = getc(inputt)) != ' ') {
               if (ss == '\n') {
                       ungetc(ss, inputt);
                       /*
                        * It's not really an error, but to flag remembered
                        * filename is to be used.
                        */
                       *errnum = -2;
               } else {
                       *errnum = -1;
                       strcpy(help_msg,
                           "space required before filename given");
               }
               return (NULL);
       }
       while (ss = getc(inputt))
               if (ss != ' ') {
                       ungetc(ss, inputt);
                       break;
               }
       for (;;) {
               ss = getc(inputt);
               if ((ss == '\\') && (l_esc == 0)) {
                       ss = getchar();
                       l_esc = 1;
               } else
                       l_esc = 0;
               if ((ss == '\n') || (ss == EOF)) {
                       l_fname[l_cnt] = '\0';
                       break;
               } else
                       if ((ss == '!') && (l_esc == 0) && (l_cnt < 2))
                               l_bang_flag = 1;
                       else
                               if ((ss != ' ') || (l_bang_flag))
                                       l_fname[l_cnt++] = ss;
                               else {
                                       *errnum = -1;
                                       return (NULL);
                               }

               if (l_cnt >= FILENAME_LEN) {
                       strcpy(help_msg, "filename+path length too long");
                       *errnum = -1;
                       ungetc('\n', inputt);
                       return (NULL);
               }
       }

       if (l_fname[0] == '\0') {
               sigspecial++;
               strcpy(l_fname, filename_current);
               sigspecial--;
               if (sigint_flag && (!sigspecial))
                       SIGINT_ACTION;
       }
       *errnum = 1;
       l_fname[FILENAME_LEN+1] = l_bang_flag;
       return (l_fname);
}