external/bsd/nvi/dist/common/delete.c

   1 /*      $NetBSD: delete.c,v 1.2 2013/11/22 15:52:05 christos Exp $ */
   2 /*-
   3  * Copyright (c) 1992, 1993, 1994
   4  *      The Regents of the University of California.  All rights reserved.
   5  * Copyright (c) 1992, 1993, 1994, 1995, 1996
   6  *      Keith Bostic.  All rights reserved.
   7  *
   8  * See the LICENSE file for redistribution information.
   9  */
  10
  11 #include "config.h"
  12
  13 #ifndef lint
  14 static const char sccsid[] = "Id: delete.c,v 10.17 2001/06/25 15:19:09 skimo Exp  (Berkeley) Date: 2001/06/25 15:19:09 ";
  15 #endif /* not lint */
  16
  17 #include <sys/types.h>
  18 #include <sys/queue.h>
  19
  20 #include <bitstring.h>
  21 #include <errno.h>
  22 #include <limits.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26
  27 #include "common.h"
  28
  29 /*
  30  * del --
  31  *      Delete a range of text.
  32  *
  33  * PUBLIC: int del __P((SCR *, MARK *, MARK *, int));
  34  */
  35 int
  36 del(SCR *sp, MARK *fm, MARK *tm, int lmode)
  37 {
  38         db_recno_t lno;
  39         size_t blen, len, nlen, tlen;
  40         CHAR_T *bp, *p;
  41         int eof, rval;
  42
  43         bp = NULL;
  44
  45         /* Case 1 -- delete in line mode. */
  46         if (lmode) {
  47                 for (lno = tm->lno; lno >= fm->lno; --lno) {
  48                         if (db_delete(sp, lno))
  49                                 return (1);
  50                         ++sp->rptlines[L_DELETED];
  51                         if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
  52                                 break;
  53                 }
  54                 goto done;
  55         }
  56
  57         /*
  58          * Case 2 -- delete to EOF.  This is a special case because it's
  59          * easier to pick it off than try and find it in the other cases.
  60          */
  61         if (db_last(sp, &lno))
  62                 return (1);
  63         if (tm->lno >= lno) {
  64                 if (tm->lno == lno) {
  65                         if (db_get(sp, lno, DBG_FATAL, &p, &len))
  66                                 return (1);
  67                         eof = tm->cno != ENTIRE_LINE && tm->cno >= len ? 1 : 0;
  68                 } else
  69                         eof = 1;
  70                 if (eof) {
  71                         for (lno = tm->lno; lno > fm->lno; --lno) {
  72                                 if (db_delete(sp, lno))
  73                                         return (1);
  74                                 ++sp->rptlines[L_DELETED];
  75                                 if (lno %
  76                                     INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
  77                                         break;
  78                         }
  79                         if (db_get(sp, fm->lno, DBG_FATAL, &p, &len))
  80                                 return (1);
  81                         GET_SPACE_RETW(sp, bp, blen, fm->cno);
  82                         MEMCPYW(bp, p, fm->cno);
  83                         if (db_set(sp, fm->lno, bp, fm->cno))
  84                                 return (1);
  85                         goto done;
  86                 }
  87         }
  88
  89         /* Case 3 -- delete within a single line. */
  90         if (tm->lno == fm->lno) {
  91                 if (db_get(sp, fm->lno, DBG_FATAL, &p, &len))
  92                         return (1);
  93                 GET_SPACE_RETW(sp, bp, blen, len);
  94                 if (fm->cno != 0)
  95                         MEMCPYW(bp, p, fm->cno);
  96                 MEMCPYW(bp + fm->cno, p + (tm->cno + 1),
  97                         len - (tm->cno + 1));
  98                 if (db_set(sp, fm->lno,
  99                     bp, len - ((tm->cno - fm->cno) + 1)))
 100                         goto err;
 101                 goto done;
 102         }
 103
 104         /*
 105          * Case 4 -- delete over multiple lines.
 106          *
 107          * Copy the start partial line into place.
 108          */
 109         if ((tlen = fm->cno) != 0) {
 110                 if (db_get(sp, fm->lno, DBG_FATAL, &p, NULL))
 111                         return (1);
 112                 GET_SPACE_RETW(sp, bp, blen, tlen + 256);
 113                 MEMCPYW(bp, p, tlen);
 114         }
 115
 116         /* Copy the end partial line into place. */
 117         if (db_get(sp, tm->lno, DBG_FATAL, &p, &len))
 118                 goto err;
 119         if (len != 0 && tm->cno != len - 1) {
 120                 /*
 121                  * XXX
 122                  * We can overflow memory here, if the total length is greater
 123                  * than SIZE_T_MAX.  The only portable way I've found to test
 124                  * is depending on the overflow being less than the value.
 125                  */
 126                 nlen = (len - (tm->cno + 1)) + tlen;
 127                 if (tlen > nlen) {
 128                         msgq(sp, M_ERR, "002|Line length overflow");
 129                         goto err;
 130                 }
 131                 if (tlen == 0) {
 132                         GET_SPACE_RETW(sp, bp, blen, nlen);
 133                 } else
 134                         ADD_SPACE_RETW(sp, bp, blen, nlen);
 135
 136                 MEMCPYW(bp + tlen, p + (tm->cno + 1), len - (tm->cno + 1));
 137                 tlen += len - (tm->cno + 1);
 138         }
 139
 140         /* Set the current line. */
 141         if (db_set(sp, fm->lno, bp, tlen))
 142                 goto err;
 143
 144         /* Delete the last and intermediate lines. */
 145         for (lno = tm->lno; lno > fm->lno; --lno) {
 146                 if (db_delete(sp, lno))
 147                         goto err;
 148                 ++sp->rptlines[L_DELETED];
 149                 if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
 150                         break;
 151         }
 152
 153 done:   rval = 0;
 154         if (0)
 155 err:            rval = 1;
 156         if (bp != NULL)
 157                 FREE_SPACEW(sp, bp, blen);
 158         return (rval);
 159 }