ex/ex_bang.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_bang.c,v 10.35 2000/07/14 14:29:20 skimo Exp $ (Berkeley) $Date: 2000/07/14 14:29:20 $";
  14 #endif /* not lint */
  15
  16 #include <sys/types.h>
  17 #include <sys/queue.h>
  18 #include <sys/time.h>
  19
  20 #include <bitstring.h>
  21 #include <errno.h>
  22 #include <limits.h>
  23 #include <stdio.h>
  24 #include <stdlib.h>
  25 #include <string.h>
  26 #include <unistd.h>
  27
  28 #include "../common/common.h"
  29 #include "../vi/vi.h"
  30
  31 /*
  32  * ex_bang -- :[line [,line]] ! command
  33  *
  34  * Pass the rest of the line after the ! character to the program named by
  35  * the O_SHELL option.
  36  *
  37  * Historical vi did NOT do shell expansion on the arguments before passing
  38  * them, only file name expansion.  This means that the O_SHELL program got
  39  * "$t" as an argument if that is what the user entered.  Also, there's a
  40  * special expansion done for the bang command.  Any exclamation points in
  41  * the user's argument are replaced by the last, expanded ! command.
  42  *
  43  * There's some fairly amazing slop in this routine to make the different
  44  * ways of getting here display the right things.  It took a long time to
  45  * get it right (wrong?), so be careful.
  46  *
  47  * PUBLIC: int ex_bang __P((SCR *, EXCMD *));
  48  */
  49 int
  50 ex_bang(sp, cmdp)
  51         SCR *sp;
  52         EXCMD *cmdp;
  53 {
  54         enum filtertype ftype;
  55         ARGS *ap;
  56         EX_PRIVATE *exp;
  57         MARK rm;
  58         db_recno_t lno;
  59         int rval;
  60         const char *msg;
  61         char *np;
  62         size_t nlen;
  63
  64         ap = cmdp->argv[0];
  65         if (ap->len == 0) {
  66                 ex_emsg(sp, cmdp->cmd->usage, EXM_USAGE);
  67                 return (1);
  68         }
  69
  70         /* Set the "last bang command" remembered value. */
  71         exp = EXP(sp);
  72         if (exp->lastbcomm != NULL)
  73                 free(exp->lastbcomm);
  74         if ((exp->lastbcomm = v_wstrdup(sp, ap->bp, ap->len)) == NULL) {
  75                 msgq(sp, M_SYSERR, NULL);
  76                 return (1);
  77         }
  78
  79         /*
  80          * If the command was modified by the expansion, it was historically
  81          * redisplayed.
  82          */
  83         if (F_ISSET(cmdp, E_MODIFY) && !F_ISSET(sp, SC_EX_SILENT)) {
  84                 /*
  85                  * Display the command if modified.  Historic ex/vi displayed
  86                  * the command if it was modified due to file name and/or bang
  87                  * expansion.  If piping lines in vi, it would be immediately
  88                  * overwritten by any error or line change reporting.
  89                  */
  90                 if (F_ISSET(sp, SC_VI))
  91                         vs_update(sp, "!", ap->bp);
  92                 else {
  93                         (void)ex_printf(sp, "!%s\n", ap->bp);
  94                         (void)ex_fflush(sp);
  95                 }
  96         }
  97
  98         /*
  99          * If no addresses were specified, run the command.  If there's an
 100          * underlying file, it's been modified and autowrite is set, write
 101          * the file back.  If the file has been modified, autowrite is not
 102          * set and the warn option is set, tell the user about the file.
 103          */
 104         if (cmdp->addrcnt == 0) {
 105                 msg = NULL;
 106                 if (sp->ep != NULL && F_ISSET(sp->ep, F_MODIFIED))
 107                         if (O_ISSET(sp, O_AUTOWRITE)) {
 108                                 if (file_aw(sp, FS_ALL))
 109                                         return (0);
 110                         } else if (O_ISSET(sp, O_WARN) &&
 111                             !F_ISSET(sp, SC_EX_SILENT))
 112                                 msg = msg_cat(sp,
 113                                     "303|File modified since last write.",
 114                                     NULL);
 115
 116                 /* If we're still in a vi screen, move out explicitly. */
 117                 INT2CHAR(sp, ap->bp, ap->len+1, np, nlen);
 118                 (void)ex_exec_proc(sp,
 119                     cmdp, np, msg, !F_ISSET(sp, SC_EX | SC_SCR_EXWROTE));
 120         }
 121
 122         /*
 123          * If addresses were specified, pipe lines from the file through the
 124          * command.
 125          *
 126          * Historically, vi lines were replaced by both the stdout and stderr
 127          * lines of the command, but ex lines by only the stdout lines.  This
 128          * makes no sense to me, so nvi makes it consistent for both, and
 129          * matches vi's historic behavior.
 130          */
 131         else {
 132                 NEEDFILE(sp, cmdp);
 133
 134                 /* Autoprint is set historically, even if the command fails. */
 135                 F_SET(cmdp, E_AUTOPRINT);
 136
 137                 /*
 138                  * !!!
 139                  * Historical vi permitted "!!" in an empty file.  When this
 140                  * happens, we arrive here with two addresses of 1,1 and a
 141                  * bad attitude.  The simple solution is to turn it into a
 142                  * FILTER_READ operation, with the exception that stdin isn't
 143                  * opened for the utility, and the cursor position isn't the
 144                  * same.  The only historic glitch (I think) is that we don't
 145                  * put an empty line into the default cut buffer, as historic
 146                  * vi did.  Imagine, if you can, my disappointment.
 147                  */
 148                 ftype = FILTER_BANG;
 149                 if (cmdp->addr1.lno == 1 && cmdp->addr2.lno == 1) {
 150                         if (db_last(sp, &lno))
 151                                 return (1);
 152                         if (lno == 0) {
 153                                 cmdp->addr1.lno = cmdp->addr2.lno = 0;
 154                                 ftype = FILTER_RBANG;
 155                         }
 156                 }
 157                 rval = ex_filter(sp, cmdp,
 158                     &cmdp->addr1, &cmdp->addr2, &rm, ap->bp, ftype);
 159
 160                 /*
 161                  * If in vi mode, move to the first nonblank.
 162                  *
 163                  * !!!
 164                  * Historic vi wasn't consistent in this area -- if you used
 165                  * a forward motion it moved to the first nonblank, but if you
 166                  * did a backward motion it didn't.  And, if you followed a
 167                  * backward motion with a forward motion, it wouldn't move to
 168                  * the nonblank for either.  Going to the nonblank generally
 169                  * seems more useful and consistent, so we do it.
 170                  */
 171                 sp->lno = rm.lno;
 172                 if (F_ISSET(sp, SC_VI)) {
 173                         sp->cno = 0;
 174                         (void)nonblank(sp, sp->lno, &sp->cno);
 175                 } else
 176                         sp->cno = rm.cno;
 177         }
 178
 179         /* Ex terminates with a bang, even if the command fails. */
 180         if (!F_ISSET(sp, SC_VI) && !F_ISSET(sp, SC_EX_SILENT))
 181                 (void)ex_puts(sp, "!\n");
 182
 183         /*
 184          * XXX
 185          * The ! commands never return an error, so that autoprint always
 186          * happens in the ex parser.
 187          */
 188         return (0);
 189 }