ex/ex_join.c

   1 /*-
   2  * Copyright (c) 1992, 1993, 1994
   3  *      The Regents of the University of California.  All rights reserved.
   4  * Copyright (c) 1992, 1993, 1994, 1995, 1996
   5  *      Keith Bostic.  All rights reserved.
   6  *
   7  * See the LICENSE file for redistribution information.
   8  */
   9
  10 #include "config.h"
  11
  12 #ifndef lint
  13 static const char sccsid[] = "$Id: ex_join.c,v 10.16 2001/06/25 15:19:16 skimo Exp $ (Berkeley) $Date: 2001/06/25 15:19:16 $";
  14 #endif /* not lint */
  15
  16 #include <sys/types.h>
  17 #include <sys/queue.h>
  18
  19 #include <bitstring.h>
  20 #include <ctype.h>
  21 #include <limits.h>
  22 #include <stdio.h>
  23 #include <stdlib.h>
  24 #include <string.h>
  25
  26 #include "../common/common.h"
  27
  28 /*
  29  * ex_join -- :[line [,line]] j[oin][!] [count] [flags]
  30  *      Join lines.
  31  *
  32  * PUBLIC: int ex_join __P((SCR *, EXCMD *));
  33  */
  34 int
  35 ex_join(SCR *sp, EXCMD *cmdp)
  36 {
  37         db_recno_t from, to;
  38         size_t blen, clen, len, tlen;
  39         int echar, extra, first;
  40         CHAR_T *bp, *tbp;
  41         CHAR_T *p;
  42
  43         NEEDFILE(sp, cmdp);
  44
  45         from = cmdp->addr1.lno;
  46         to = cmdp->addr2.lno;
  47
  48         /* Check for no lines to join. */
  49         if (!db_exist(sp, from + 1)) {
  50                 msgq(sp, M_ERR, "131|No following lines to join");
  51                 return (1);
  52         }
  53
  54         GET_SPACE_RETW(sp, bp, blen, 256);
  55
  56         /*
  57          * The count for the join command was off-by-one,
  58          * historically, to other counts for other commands.
  59          */
  60         if (FL_ISSET(cmdp->iflags, E_C_COUNT))
  61                 ++cmdp->addr2.lno;
  62
  63         /*
  64          * If only a single address specified, or, the same address
  65          * specified twice, the from/two addresses will be the same.
  66          */
  67         if (cmdp->addr1.lno == cmdp->addr2.lno)
  68                 ++cmdp->addr2.lno;
  69
  70         clen = tlen = 0;
  71         for (first = 1,
  72             from = cmdp->addr1.lno, to = cmdp->addr2.lno; from <= to; ++from) {
  73                 /*
  74                  * Get next line.  Historic versions of vi allowed "10J" while
  75                  * less than 10 lines from the end-of-file, so we do too.
  76                  */
  77                 if (db_get(sp, from, 0, &p, &len)) {
  78                         cmdp->addr2.lno = from - 1;
  79                         break;
  80                 }
  81
  82                 /* Empty lines just go away. */
  83                 if (len == 0)
  84                         continue;
  85
  86                 /*
  87                  * Get more space if necessary.  Note, tlen isn't the length
  88                  * of the new line, it's roughly the amount of space needed.
  89                  * tbp - bp is the length of the new line.
  90                  */
  91                 tlen += len + 2;
  92                 ADD_SPACE_RETW(sp, bp, blen, tlen);
  93                 tbp = bp + clen;
  94
  95                 /*
  96                  * Historic practice:
  97                  *
  98                  * If force specified, join without modification.
  99                  * If the current line ends with whitespace, strip leading
 100                  *    whitespace from the joined line.
 101                  * If the next line starts with a ), do nothing.
 102                  * If the current line ends with ., insert two spaces.
 103                  * Else, insert one space.
 104                  *
 105                  * One change -- add ? and ! to the list of characters for
 106                  * which we insert two spaces.  I expect that POSIX 1003.2
 107                  * will require this as well.
 108                  *
 109                  * Echar is the last character in the last line joined.
 110                  */
 111                 extra = 0;
 112                 if (!first && !FL_ISSET(cmdp->iflags, E_C_FORCE)) {
 113                         if (isblank(echar))
 114                                 for (; len && isblank(*p); --len, ++p);
 115                         else if (p[0] != ')') {
 116                                 if (strchr(".?!", echar)) {
 117                                         *tbp++ = ' ';
 118                                         ++clen;
 119                                         extra = 1;
 120                                 }
 121                                 *tbp++ = ' ';
 122                                 ++clen;
 123                                 for (; len && isblank(*p); --len, ++p);
 124                         }
 125                 }
 126
 127                 if (len != 0) {
 128                         MEMCPYW(tbp, p, len);
 129                         tbp += len;
 130                         clen += len;
 131                         echar = p[len - 1];
 132                 } else
 133                         echar = ' ';
 134
 135                 /*
 136                  * Historic practice for vi was to put the cursor at the first
 137                  * inserted whitespace character, if there was one, or the
 138                  * first character of the joined line, if there wasn't, or the
 139                  * last character of the line if joined to an empty line.  If
 140                  * a count was specified, the cursor was moved as described
 141                  * for the first line joined, ignoring subsequent lines.  If
 142                  * the join was a ':' command, the cursor was placed at the
 143                  * first non-blank character of the line unless the cursor was
 144                  * "attracted" to the end of line when the command was executed
 145                  * in which case it moved to the new end of line.  There are
 146                  * probably several more special cases, but frankly, my dear,
 147                  * I don't give a damn.  This implementation puts the cursor
 148                  * on the first inserted whitespace character, the first
 149                  * character of the joined line, or the last character of the
 150                  * line regardless.  Note, if the cursor isn't on the joined
 151                  * line (possible with : commands), it is reset to the starting
 152                  * line.
 153                  */
 154                 if (first) {
 155                         sp->cno = (tbp - bp) - (1 + extra);
 156                         first = 0;
 157                 } else
 158                         sp->cno = (tbp - bp) - len - (1 + extra);
 159         }
 160         sp->lno = cmdp->addr1.lno;
 161
 162         /* Delete the joined lines. */
 163         for (from = cmdp->addr1.lno, to = cmdp->addr2.lno; to > from; --to)
 164                 if (db_delete(sp, to))
 165                         goto err;
 166
 167         /* If the original line changed, reset it. */
 168         if (!first && db_set(sp, from, bp, tbp - bp)) {
 169 err:            FREE_SPACEW(sp, bp, blen);
 170                 return (1);
 171         }
 172         FREE_SPACEW(sp, bp, blen);
 173
 174         sp->rptlines[L_JOINED] += (cmdp->addr2.lno - cmdp->addr1.lno) + 1;
 175         return (0);
 176 }