contrib/nvi/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[] = "@(#)ex_join.c     10.10 (Berkeley) 9/15/96";
  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(sp, cmdp)
  36         SCR *sp;
  37         EXCMD *cmdp;
  38 {
  39         recno_t from, to;
  40         size_t blen, clen, len, tlen;
  41         int echar, extra, first;
  42         char *bp, *p, *tbp;
  43
  44         NEEDFILE(sp, cmdp);
  45
  46         from = cmdp->addr1.lno;
  47         to = cmdp->addr2.lno;
  48
  49         /* Check for no lines to join. */
  50         if (!db_exist(sp, from + 1)) {
  51                 msgq(sp, M_ERR, "131|No following lines to join");
  52                 return (1);
  53         }
  54
  55         GET_SPACE_RET(sp, bp, blen, 256);
  56
  57         /*
  58          * The count for the join command was off-by-one,
  59          * historically, to other counts for other commands.
  60          */
  61         if (FL_ISSET(cmdp->iflags, E_C_COUNT))
  62                 ++cmdp->addr2.lno;
  63
  64         /*
  65          * If only a single address specified, or, the same address
  66          * specified twice, the from/two addresses will be the same.
  67          */
  68         if (cmdp->addr1.lno == cmdp->addr2.lno)
  69                 ++cmdp->addr2.lno;
  70
  71         clen = tlen = 0;
  72         for (first = 1,
  73             from = cmdp->addr1.lno, to = cmdp->addr2.lno; from <= to; ++from) {
  74                 /*
  75                  * Get next line.  Historic versions of vi allowed "10J" while
  76                  * less than 10 lines from the end-of-file, so we do too.
  77                  */
  78                 if (db_get(sp, from, 0, &p, &len)) {
  79                         cmdp->addr2.lno = from - 1;
  80                         break;
  81                 }
  82
  83                 /* Empty lines just go away. */
  84                 if (len == 0)
  85                         continue;
  86
  87                 /*
  88                  * Get more space if necessary.  Note, tlen isn't the length
  89                  * of the new line, it's roughly the amount of space needed.
  90                  * tbp - bp is the length of the new line.
  91                  */
  92                 tlen += len + 2;
  93                 ADD_SPACE_RET(sp, bp, blen, tlen);
  94                 tbp = bp + clen;
  95
  96                 /*
  97                  * Historic practice:
  98                  *
  99                  * If force specified, join without modification.
 100                  * If the current line ends with whitespace, strip leading
 101                  *    whitespace from the joined line.
 102                  * If the next line starts with a ), do nothing.
 103                  * If the current line ends with ., insert two spaces.
 104                  * Else, insert one space.
 105                  *
 106                  * One change -- add ? and ! to the list of characters for
 107                  * which we insert two spaces.  I expect that POSIX 1003.2
 108                  * will require this as well.
 109                  *
 110                  * Echar is the last character in the last line joined.
 111                  */
 112                 extra = 0;
 113                 if (!first && !FL_ISSET(cmdp->iflags, E_C_FORCE)) {
 114                         if (isblank(echar))
 115                                 for (; len && isblank(*p); --len, ++p);
 116                         else if (p[0] != ')') {
 117                                 if (strchr(".?!", echar)) {
 118                                         *tbp++ = ' ';
 119                                         ++clen;
 120                                         extra = 1;
 121                                 }
 122                                 *tbp++ = ' ';
 123                                 ++clen;
 124                                 for (; len && isblank(*p); --len, ++p);
 125                         }
 126                 }
 127
 128                 if (len != 0) {
 129                         memcpy(tbp, p, len);
 130                         tbp += len;
 131                         clen += len;
 132                         echar = p[len - 1];
 133                 } else
 134                         echar = ' ';
 135
 136                 /*
 137                  * Historic practice for vi was to put the cursor at the first
 138                  * inserted whitespace character, if there was one, or the
 139                  * first character of the joined line, if there wasn't, or the
 140                  * last character of the line if joined to an empty line.  If
 141                  * a count was specified, the cursor was moved as described
 142                  * for the first line joined, ignoring subsequent lines.  If
 143                  * the join was a ':' command, the cursor was placed at the
 144                  * first non-blank character of the line unless the cursor was
 145                  * "attracted" to the end of line when the command was executed
 146                  * in which case it moved to the new end of line.  There are
 147                  * probably several more special cases, but frankly, my dear,
 148                  * I don't give a damn.  This implementation puts the cursor
 149                  * on the first inserted whitespace character, the first
 150                  * character of the joined line, or the last character of the
 151                  * line regardless.  Note, if the cursor isn't on the joined
 152                  * line (possible with : commands), it is reset to the starting
 153                  * line.
 154                  */
 155                 if (first) {
 156                         sp->cno = (tbp - bp) - (1 + extra);
 157                         first = 0;
 158                 } else
 159                         sp->cno = (tbp - bp) - len - (1 + extra);
 160         }
 161         sp->lno = cmdp->addr1.lno;
 162
 163         /* Delete the joined lines. */
 164         for (from = cmdp->addr1.lno, to = cmdp->addr2.lno; to > from; --to)
 165                 if (db_delete(sp, to))
 166                         goto err;
 167
 168         /* If the original line changed, reset it. */
 169         if (!first && db_set(sp, from, bp, tbp - bp)) {
 170 err:            FREE_SPACE(sp, bp, blen);
 171                 return (1);
 172         }
 173         FREE_SPACE(sp, bp, blen);
 174
 175         sp->rptlines[L_JOINED] += (cmdp->addr2.lno - cmdp->addr1.lno) + 1;
 176         return (0);
 177 }