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

   1 /*      $NetBSD: delete.c,v 1.3 2014/01/26 21:43:45 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 #include <sys/cdefs.h>
  14 #if 0
  15 #ifndef lint
  16 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 ";
  17 #endif /* not lint */
  18 #else
  19 __RCSID("$NetBSD: delete.c,v 1.3 2014/01/26 21:43:45 christos Exp $");
  20 #endif
  21
  22 #include <sys/types.h>
  23 #include <sys/queue.h>
  24
  25 #include <bitstring.h>
  26 #include <errno.h>
  27 #include <limits.h>
  28 #include <stdio.h>
  29 #include <stdlib.h>
  30 #include <string.h>
  31
  32 #include "common.h"
  33
  34 /*
  35  * del --
  36  *      Delete a range of text.
  37  *
  38  * PUBLIC: int del __P((SCR *, MARK *, MARK *, int));
  39  */
  40 int
  41 del(SCR *sp, MARK *fm, MARK *tm, int lmode)
  42 {
  43         db_recno_t lno;
  44         size_t blen, len, nlen, tlen;
  45         CHAR_T *bp, *p;
  46         int eof, rval;
  47
  48         bp = NULL;
  49
  50         /* Case 1 -- delete in line mode. */
  51         if (lmode) {
  52                 for (lno = tm->lno; lno >= fm->lno; --lno) {
  53                         if (db_delete(sp, lno))
  54                                 return (1);
  55                         ++sp->rptlines[L_DELETED];
  56                         if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
  57                                 break;
  58                 }
  59                 goto done;
  60         }
  61
  62         /*
  63          * Case 2 -- delete to EOF.  This is a special case because it's
  64          * easier to pick it off than try and find it in the other cases.
  65          */
  66         if (db_last(sp, &lno))
  67                 return (1);
  68         if (tm->lno >= lno) {
  69                 if (tm->lno == lno) {
  70                         if (db_get(sp, lno, DBG_FATAL, &p, &len))
  71                                 return (1);
  72                         eof = tm->cno != ENTIRE_LINE && tm->cno >= len ? 1 : 0;
  73                 } else
  74                         eof = 1;
  75                 if (eof) {
  76                         for (lno = tm->lno; lno > fm->lno; --lno) {
  77                                 if (db_delete(sp, lno))
  78                                         return (1);
  79                                 ++sp->rptlines[L_DELETED];
  80                                 if (lno %
  81                                     INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
  82                                         break;
  83                         }
  84                         if (db_get(sp, fm->lno, DBG_FATAL, &p, &len))
  85                                 return (1);
  86                         GET_SPACE_RETW(sp, bp, blen, fm->cno);
  87                         MEMCPYW(bp, p, fm->cno);
  88                         if (db_set(sp, fm->lno, bp, fm->cno))
  89                                 return (1);
  90                         goto done;
  91                 }
  92         }
  93
  94         /* Case 3 -- delete within a single line. */
  95         if (tm->lno == fm->lno) {
  96                 if (db_get(sp, fm->lno, DBG_FATAL, &p, &len))
  97                         return (1);
  98                 GET_SPACE_RETW(sp, bp, blen, len);
  99                 if (fm->cno != 0)
 100                         MEMCPYW(bp, p, fm->cno);
 101                 MEMCPYW(bp + fm->cno, p + (tm->cno + 1),
 102                         len - (tm->cno + 1));
 103                 if (db_set(sp, fm->lno,
 104                     bp, len - ((tm->cno - fm->cno) + 1)))
 105                         goto err;
 106                 goto done;
 107         }
 108
 109         /*
 110          * Case 4 -- delete over multiple lines.
 111          *
 112          * Copy the start partial line into place.
 113          */
 114         if ((tlen = fm->cno) != 0) {
 115                 if (db_get(sp, fm->lno, DBG_FATAL, &p, NULL))
 116                         return (1);
 117                 GET_SPACE_RETW(sp, bp, blen, tlen + 256);
 118                 MEMCPYW(bp, p, tlen);
 119         }
 120
 121         /* Copy the end partial line into place. */
 122         if (db_get(sp, tm->lno, DBG_FATAL, &p, &len))
 123                 goto err;
 124         if (len != 0 && tm->cno != len - 1) {
 125                 /*
 126                  * XXX
 127                  * We can overflow memory here, if the total length is greater
 128                  * than SIZE_T_MAX.  The only portable way I've found to test
 129                  * is depending on the overflow being less than the value.
 130                  */
 131                 nlen = (len - (tm->cno + 1)) + tlen;
 132                 if (tlen > nlen) {
 133                         msgq(sp, M_ERR, "002|Line length overflow");
 134                         goto err;
 135                 }
 136                 if (tlen == 0) {
 137                         GET_SPACE_RETW(sp, bp, blen, nlen);
 138                 } else
 139                         ADD_SPACE_RETW(sp, bp, blen, nlen);
 140
 141                 MEMCPYW(bp + tlen, p + (tm->cno + 1), len - (tm->cno + 1));
 142                 tlen += len - (tm->cno + 1);
 143         }
 144
 145         /* Set the current line. */
 146         if (db_set(sp, fm->lno, bp, tlen))
 147                 goto err;
 148
 149         /* Delete the last and intermediate lines. */
 150         for (lno = tm->lno; lno > fm->lno; --lno) {
 151                 if (db_delete(sp, lno))
 152                         goto err;
 153                 ++sp->rptlines[L_DELETED];
 154                 if (lno % INTERRUPT_CHECK == 0 && INTERRUPTED(sp))
 155                         break;
 156         }
 157
 158 done:   rval = 0;
 159         if (0)
 160 err:            rval = 1;
 161         if (bp != NULL)
 162                 FREE_SPACEW(sp, bp, blen);
 163         return (rval);
 164 }