contrib/nvi/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[] = "@(#)ex_bang.c     10.33 (Berkeley) 9/23/96";
  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         recno_t lno;
  59         int rval;
  60         const char *msg;
  61
  62         ap = cmdp->argv[0];
  63         if (ap->len == 0) {
  64                 ex_emsg(sp, cmdp->cmd->usage, EXM_USAGE);
  65                 return (1);
  66         }
  67
  68         /* Set the "last bang command" remembered value. */
  69         exp = EXP(sp);
  70         if (exp->lastbcomm != NULL)
  71                 free(exp->lastbcomm);
  72         if ((exp->lastbcomm = strdup(ap->bp)) == NULL) {
  73                 msgq(sp, M_SYSERR, NULL);
  74                 return (1);
  75         }
  76
  77         /*
  78          * If the command was modified by the expansion, it was historically
  79          * redisplayed.
  80          */
  81         if (F_ISSET(cmdp, E_MODIFY) && !F_ISSET(sp, SC_EX_SILENT)) {
  82                 /*
  83                  * Display the command if modified.  Historic ex/vi displayed
  84                  * the command if it was modified due to file name and/or bang
  85                  * expansion.  If piping lines in vi, it would be immediately
  86                  * overwritten by any error or line change reporting.
  87                  */
  88                 if (F_ISSET(sp, SC_VI))
  89                         vs_update(sp, "!", ap->bp);
  90                 else {
  91                         (void)ex_printf(sp, "!%s\n", ap->bp);
  92                         (void)ex_fflush(sp);
  93                 }
  94         }
  95
  96         /*
  97          * If no addresses were specified, run the command.  If there's an
  98          * underlying file, it's been modified and autowrite is set, write
  99          * the file back.  If the file has been modified, autowrite is not
 100          * set and the warn option is set, tell the user about the file.
 101          */
 102         if (cmdp->addrcnt == 0) {
 103                 msg = NULL;
 104                 if (sp->ep != NULL && F_ISSET(sp->ep, F_MODIFIED))
 105                         if (O_ISSET(sp, O_AUTOWRITE)) {
 106                                 if (file_aw(sp, FS_ALL))
 107                                         return (0);
 108                         } else if (O_ISSET(sp, O_WARN) &&
 109                             !F_ISSET(sp, SC_EX_SILENT))
 110                                 msg = msg_cat(sp,
 111                                     "303|File modified since last write.",
 112                                     NULL);
 113
 114                 /* If we're still in a vi screen, move out explicitly. */
 115                 (void)ex_exec_proc(sp,
 116                     cmdp, ap->bp, msg, !F_ISSET(sp, SC_EX | SC_SCR_EXWROTE));
 117         }
 118
 119         /*
 120          * If addresses were specified, pipe lines from the file through the
 121          * command.
 122          *
 123          * Historically, vi lines were replaced by both the stdout and stderr
 124          * lines of the command, but ex lines by only the stdout lines.  This
 125          * makes no sense to me, so nvi makes it consistent for both, and
 126          * matches vi's historic behavior.
 127          */
 128         else {
 129                 NEEDFILE(sp, cmdp);
 130
 131                 /* Autoprint is set historically, even if the command fails. */
 132                 F_SET(cmdp, E_AUTOPRINT);
 133
 134                 /*
 135                  * !!!
 136                  * Historical vi permitted "!!" in an empty file.  When this
 137                  * happens, we arrive here with two addresses of 1,1 and a
 138                  * bad attitude.  The simple solution is to turn it into a
 139                  * FILTER_READ operation, with the exception that stdin isn't
 140                  * opened for the utility, and the cursor position isn't the
 141                  * same.  The only historic glitch (I think) is that we don't
 142                  * put an empty line into the default cut buffer, as historic
 143                  * vi did.  Imagine, if you can, my disappointment.
 144                  */
 145                 ftype = FILTER_BANG;
 146                 if (cmdp->addr1.lno == 1 && cmdp->addr2.lno == 1) {
 147                         if (db_last(sp, &lno))
 148                                 return (1);
 149                         if (lno == 0) {
 150                                 cmdp->addr1.lno = cmdp->addr2.lno = 0;
 151                                 ftype = FILTER_RBANG;
 152                         }
 153                 }
 154                 rval = ex_filter(sp, cmdp,
 155                     &cmdp->addr1, &cmdp->addr2, &rm, ap->bp, ftype);
 156
 157                 /*
 158                  * If in vi mode, move to the first nonblank.
 159                  *
 160                  * !!!
 161                  * Historic vi wasn't consistent in this area -- if you used
 162                  * a forward motion it moved to the first nonblank, but if you
 163                  * did a backward motion it didn't.  And, if you followed a
 164                  * backward motion with a forward motion, it wouldn't move to
 165                  * the nonblank for either.  Going to the nonblank generally
 166                  * seems more useful and consistent, so we do it.
 167                  */
 168                 sp->lno = rm.lno;
 169                 if (F_ISSET(sp, SC_VI)) {
 170                         sp->cno = 0;
 171                         (void)nonblank(sp, sp->lno, &sp->cno);
 172                 } else
 173                         sp->cno = rm.cno;
 174         }
 175
 176         /* Ex terminates with a bang, even if the command fails. */
 177         if (!F_ISSET(sp, SC_VI) && !F_ISSET(sp, SC_EX_SILENT))
 178                 (void)ex_puts(sp, "!\n");
 179
 180         /*
 181          * XXX
 182          * The ! commands never return an error, so that autoprint always
 183          * happens in the ex parser.
 184          */
 185         return (0);
 186 }