1 /* $OpenBSD: ex_bang.c,v 1.12 2022/04/22 15:48:29 millert Exp $ */
2
3 /*-
4 * Copyright (c) 1992, 1993, 1994
5 * The Regents of the University of California. All rights reserved.
6 * Copyright (c) 1992, 1993, 1994, 1995, 1996
7 * Keith Bostic. All rights reserved.
8 *
9 * See the LICENSE file for redistribution information.
10 */
11
12 #include "config.h"
13
14 #include <sys/types.h>
15 #include <sys/queue.h>
16 #include <sys/time.h>
17
18 #include <bitstring.h>
19 #include <errno.h>
20 #include <limits.h>
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <unistd.h>
25
26 #include "../common/common.h"
27 #include "../vi/vi.h"
28
29 /*
30 * ex_bang -- :[line [,line]] ! command
31 *
32 * Pass the rest of the line after the ! character to the program named by
33 * the O_SHELL option.
34 *
35 * Historical vi did NOT do shell expansion on the arguments before passing
36 * them, only file name expansion. This means that the O_SHELL program got
37 * "$t" as an argument if that is what the user entered. Also, there's a
38 * special expansion done for the bang command. Any exclamation points in
39 * the user's argument are replaced by the last, expanded ! command.
40 *
41 * There's some fairly amazing slop in this routine to make the different
42 * ways of getting here display the right things. It took a long time to
43 * get it right (wrong?), so be careful.
44 *
45 * PUBLIC: int ex_bang(SCR *, EXCMD *);
46 */
47 int
ex_bang(SCR * sp,EXCMD * cmdp)48 ex_bang(SCR *sp, EXCMD *cmdp)
49 {
50 enum filtertype ftype;
51 ARGS *ap;
52 EX_PRIVATE *exp;
53 MARK rm;
54 recno_t lno;
55 int rval;
56 const char *msg;
57
58 ap = cmdp->argv[0];
59 if (ap->len == 0) {
60 ex_emsg(sp, cmdp->cmd->usage, EXM_USAGE);
61 return (1);
62 }
63
64 /* Set the "last bang command" remembered value. */
65 exp = EXP(sp);
66 free(exp->lastbcomm);
67 if ((exp->lastbcomm = strdup(ap->bp)) == NULL) {
68 msgq(sp, M_SYSERR, NULL);
69 return (1);
70 }
71
72 /*
73 * If the command was modified by the expansion, it was historically
74 * redisplayed.
75 */
76 if (F_ISSET(cmdp, E_MODIFY) && !F_ISSET(sp, SC_EX_SILENT)) {
77 /*
78 * Display the command if modified. Historic ex/vi displayed
79 * the command if it was modified due to file name and/or bang
80 * expansion. If piping lines in vi, it would be immediately
81 * overwritten by any error or line change reporting.
82 */
83 if (F_ISSET(sp, SC_VI))
84 vs_update(sp, "!", ap->bp);
85 else {
86 (void)ex_printf(sp, "!%s\n", ap->bp);
87 (void)ex_fflush(sp);
88 }
89 }
90
91 /*
92 * If no addresses were specified, run the command. If there's an
93 * underlying file, it's been modified and autowrite is set, write
94 * the file back. If the file has been modified, autowrite is not
95 * set and the warn option is set, tell the user about the file.
96 */
97 if (cmdp->addrcnt == 0) {
98 msg = NULL;
99 if (sp->ep != NULL && F_ISSET(sp->ep, F_MODIFIED)) {
100 if (O_ISSET(sp, O_AUTOWRITE)) {
101 if (file_aw(sp, FS_ALL))
102 return (0);
103 } else if (O_ISSET(sp, O_WARN) &&
104 !F_ISSET(sp, SC_EX_SILENT))
105 msg = "File modified since last write.";
106 }
107
108 /* If we're still in a vi screen, move out explicitly. */
109 (void)ex_exec_proc(sp,
110 cmdp, ap->bp, msg, !F_ISSET(sp, SC_EX | SC_SCR_EXWROTE));
111 }
112
113 /*
114 * If addresses were specified, pipe lines from the file through the
115 * command.
116 *
117 * Historically, vi lines were replaced by both the stdout and stderr
118 * lines of the command, but ex lines by only the stdout lines. This
119 * makes no sense to me, so nvi makes it consistent for both, and
120 * matches vi's historic behavior.
121 */
122 else {
123 NEEDFILE(sp, cmdp);
124
125 /* Autoprint is set historically, even if the command fails. */
126 F_SET(cmdp, E_AUTOPRINT);
127
128 /*
129 * !!!
130 * Historical vi permitted "!!" in an empty file. When this
131 * happens, we arrive here with two addresses of 1,1 and a
132 * bad attitude. The simple solution is to turn it into a
133 * FILTER_READ operation, with the exception that stdin isn't
134 * opened for the utility, and the cursor position isn't the
135 * same. The only historic glitch (I think) is that we don't
136 * put an empty line into the default cut buffer, as historic
137 * vi did. Imagine, if you can, my disappointment.
138 */
139 ftype = FILTER_BANG;
140 if (cmdp->addr1.lno == 1 && cmdp->addr2.lno == 1) {
141 if (db_last(sp, &lno))
142 return (1);
143 if (lno == 0) {
144 cmdp->addr1.lno = cmdp->addr2.lno = 0;
145 ftype = FILTER_RBANG;
146 }
147 }
148 rval = ex_filter(sp, cmdp,
149 &cmdp->addr1, &cmdp->addr2, &rm, ap->bp, ftype);
150
151 /*
152 * If in vi mode, move to the first nonblank.
153 *
154 * !!!
155 * Historic vi wasn't consistent in this area -- if you used
156 * a forward motion it moved to the first nonblank, but if you
157 * did a backward motion it didn't. And, if you followed a
158 * backward motion with a forward motion, it wouldn't move to
159 * the nonblank for either. Going to the nonblank generally
160 * seems more useful and consistent, so we do it.
161 */
162 sp->lno = rm.lno;
163 if (F_ISSET(sp, SC_VI)) {
164 sp->cno = 0;
165 (void)nonblank(sp, sp->lno, &sp->cno);
166 } else
167 sp->cno = rm.cno;
168 }
169
170 /* Ex terminates with a bang, even if the command fails. */
171 if (!F_ISSET(sp, SC_VI) && !F_ISSET(sp, SC_EX_SILENT))
172 (void)ex_puts(sp, "!\n");
173
174 /* Apply expandtab to the new text */
175 if (O_ISSET(sp, O_EXPANDTAB))
176 ex_retab(sp, cmdp);
177
178 /*
179 * XXX
180 * The ! commands never return an error, so that autoprint always
181 * happens in the ex parser.
182 */
183 return (0);
184 }
185