xref: /freebsd/contrib/nvi/ex/ex_bang.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
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 }
187