1 /* $OpenBSD: ex_shell.c,v 1.15 2015/03/28 12:54:37 bcallah 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/queue.h>
15 #include <sys/wait.h>
16
17 #include <bitstring.h>
18 #include <ctype.h>
19 #include <errno.h>
20 #include <limits.h>
21 #include <signal.h>
22 #include <stdio.h>
23 #include <stdlib.h>
24 #include <string.h>
25 #include <unistd.h>
26
27 #include "../common/common.h"
28
29 #define MINIMUM(a, b) (((a) < (b)) ? (a) : (b))
30
31 /*
32 * ex_shell -- :sh[ell]
33 * Invoke the program named in the SHELL environment variable
34 * with the argument -i.
35 *
36 * PUBLIC: int ex_shell(SCR *, EXCMD *);
37 */
38 int
ex_shell(SCR * sp,EXCMD * cmdp)39 ex_shell(SCR *sp, EXCMD *cmdp)
40 {
41 int rval;
42 char buf[PATH_MAX];
43
44 /* We'll need a shell. */
45 if (opts_empty(sp, O_SHELL, 0))
46 return (1);
47
48 /*
49 * XXX
50 * Assumes all shells use -i.
51 */
52 (void)snprintf(buf, sizeof(buf), "%s -i", O_STR(sp, O_SHELL));
53
54 /* Restore the window name. */
55 (void)sp->gp->scr_rename(sp, NULL, 0);
56
57 /* If we're still in a vi screen, move out explicitly. */
58 rval = ex_exec_proc(sp, cmdp, buf, NULL, !F_ISSET(sp, SC_SCR_EXWROTE));
59
60 /* Set the window name. */
61 (void)sp->gp->scr_rename(sp, sp->frp->name, 1);
62
63 /*
64 * !!!
65 * Historically, vi didn't require a continue message after the
66 * return of the shell. Match it.
67 */
68 F_SET(sp, SC_EX_WAIT_NO);
69
70 return (rval);
71 }
72
73 /*
74 * ex_exec_proc --
75 * Run a separate process.
76 *
77 * PUBLIC: int ex_exec_proc(SCR *, EXCMD *, char *, const char *, int);
78 */
79 int
ex_exec_proc(SCR * sp,EXCMD * cmdp,char * cmd,const char * msg,int need_newline)80 ex_exec_proc(SCR *sp, EXCMD *cmdp, char *cmd, const char *msg,
81 int need_newline)
82 {
83 GS *gp;
84 const char *name;
85 pid_t pid;
86
87 gp = sp->gp;
88
89 /* We'll need a shell. */
90 if (opts_empty(sp, O_SHELL, 0))
91 return (1);
92
93 /* Enter ex mode. */
94 if (F_ISSET(sp, SC_VI)) {
95 if (gp->scr_screen(sp, SC_EX)) {
96 ex_emsg(sp, cmdp->cmd->name, EXM_NOCANON);
97 return (1);
98 }
99 (void)gp->scr_attr(sp, SA_ALTERNATE, 0);
100 F_SET(sp, SC_SCR_EX | SC_SCR_EXWROTE);
101 }
102
103 /* Put out additional newline, message. */
104 if (need_newline)
105 (void)ex_puts(sp, "\n");
106 if (msg != NULL) {
107 (void)ex_puts(sp, msg);
108 (void)ex_puts(sp, "\n");
109 }
110 (void)ex_fflush(sp);
111
112 switch (pid = vfork()) {
113 case -1: /* Error. */
114 msgq(sp, M_SYSERR, "vfork");
115 return (1);
116 case 0: /* Utility. */
117 if ((name = strrchr(O_STR(sp, O_SHELL), '/')) == NULL)
118 name = O_STR(sp, O_SHELL);
119 else
120 ++name;
121 execl(O_STR(sp, O_SHELL), name, "-c", cmd, (char *)NULL);
122 msgq_str(sp, M_SYSERR, O_STR(sp, O_SHELL), "execl: %s");
123 _exit(127);
124 /* NOTREACHED */
125 default: /* Parent. */
126 return (proc_wait(sp, pid, cmd, 0, 0));
127 }
128 /* NOTREACHED */
129 }
130
131 /*
132 * proc_wait --
133 * Wait for one of the processes.
134 *
135 * !!!
136 * The pid_t type varies in size from a short to a long depending on the
137 * system. It has to be cast into something or the standard promotion
138 * rules get you. I'm using a long based on the belief that nobody is
139 * going to make it unsigned and it's unlikely to be a quad.
140 *
141 * PUBLIC: int proc_wait(SCR *, pid_t, const char *, int, int);
142 */
143 int
proc_wait(SCR * sp,pid_t pid,const char * cmd,int silent,int okpipe)144 proc_wait(SCR *sp, pid_t pid, const char *cmd, int silent, int okpipe)
145 {
146 size_t len;
147 int nf, pstat;
148 char *p;
149
150 /* Wait for the utility, ignoring interruptions. */
151 for (;;) {
152 errno = 0;
153 if (waitpid(pid, &pstat, 0) != -1)
154 break;
155 if (errno != EINTR) {
156 msgq(sp, M_SYSERR, "waitpid");
157 return (1);
158 }
159 }
160
161 /*
162 * Display the utility's exit status. Ignore SIGPIPE from the
163 * parent-writer, as that only means that the utility chose to
164 * exit before reading all of its input.
165 */
166 if (WIFSIGNALED(pstat) && (!okpipe || WTERMSIG(pstat) != SIGPIPE)) {
167 for (; isblank(*cmd); ++cmd);
168 p = msg_print(sp, cmd, &nf);
169 len = strlen(p);
170 msgq(sp, M_ERR, "%.*s%s: received signal: %s%s",
171 MINIMUM(len, 20), p, len > 20 ? " ..." : "",
172 strsignal(WTERMSIG(pstat)),
173 WCOREDUMP(pstat) ? "; core dumped" : "");
174 if (nf)
175 FREE_SPACE(sp, p, 0);
176 return (1);
177 }
178
179 if (WIFEXITED(pstat) && WEXITSTATUS(pstat)) {
180 /*
181 * Remain silent for "normal" errors when doing shell file
182 * name expansions, they almost certainly indicate nothing
183 * more than a failure to match.
184 *
185 * Remain silent for vi read filter errors. It's historic
186 * practice.
187 */
188 if (!silent) {
189 for (; isblank(*cmd); ++cmd);
190 p = msg_print(sp, cmd, &nf);
191 len = strlen(p);
192 msgq(sp, M_ERR, "%.*s%s: exited with status %d",
193 MINIMUM(len, 20), p, len > 20 ? " ..." : "",
194 WEXITSTATUS(pstat));
195 if (nf)
196 FREE_SPACE(sp, p, 0);
197 }
198 return (1);
199 }
200 return (0);
201 }
202