xref: /freebsd/contrib/dialog/prgbox.c (revision 884a2a699669ec61e2366e3e358342dbc94be24a)
1 /*
2  *  $Id: prgbox.c,v 1.6 2011/03/02 09:59:26 tom Exp $
3  *
4  *  prgbox.c -- implements the prg box
5  *
6  *  Copyright 2011	Thomas E. Dickey
7  *
8  *  This program is free software; you can redistribute it and/or modify
9  *  it under the terms of the GNU Lesser General Public License as
10  *  published by the Free Software Foundation; either version 2.1 of the
11  *  License, or (at your option) any later version.
12  *
13  *  This program is distributed in the hope that it will be useful, but
14  *  WITHOUT ANY WARRANTY; without even the implied warranty of
15  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16  *  Lesser General Public License for more details.
17  *
18  *  You should have received a copy of the GNU Lesser General Public
19  *  License along with this program; if not, write to
20  *	Free Software Foundation, Inc.
21  *	51 Franklin St., Fifth Floor
22  *	Boston, MA 02110, USA.
23  */
24 
25 #include <dialog.h>
26 
27 /*
28  * Open a pipe which ties stderr and stdout together.
29  */
30 static FILE *
31 dlg_popen(const char *command, const char *type)
32 {
33     FILE *result = 0;
34     int fd[2];
35     int pid;
36     const char *argv[4];
37 
38     if ((*type == 'r' || *type != 'w') && pipe(fd) == 0) {
39 	switch (pid = fork()) {
40 	case -1:		/* Error. */
41 	    (void) close(fd[0]);
42 	    (void) close(fd[1]);
43 	    break;
44 	case 0:		/* child. */
45 	    if (*type == 'r') {
46 		if (fd[1] != STDOUT_FILENO) {
47 		    (void) dup2(fd[1], STDOUT_FILENO);
48 		    (void) close(fd[1]);
49 		}
50 		(void) dup2(STDOUT_FILENO, STDERR_FILENO);
51 		(void) close(fd[0]);
52 	    } else {
53 		if (fd[0] != STDIN_FILENO) {
54 		    (void) dup2(fd[0], STDIN_FILENO);
55 		    (void) close(fd[0]);
56 		}
57 		(void) close(fd[1]);
58 		(void) close(STDERR_FILENO);
59 	    }
60 	    /*
61 	     * Bourne shell needs "-c" option to force it to use only the
62 	     * given command.  Also, it needs the command to be parsed into
63 	     * tokens.
64 	     */
65 	    argv[0] = "sh";
66 	    argv[1] = "-c";
67 	    argv[2] = command;
68 	    argv[3] = NULL;
69 	    execvp("sh", (char **)argv);
70 	    _exit(127);
71 	    /* NOTREACHED */
72 	default:		/* parent */
73 	    if (*type == 'r') {
74 		result = fdopen(fd[0], type);
75 		(void) close(fd[1]);
76 	    } else {
77 		result = fdopen(fd[1], type);
78 		(void) close(fd[0]);
79 	    }
80 	    break;
81 	}
82     }
83 
84     return result;
85 }
86 
87 /*
88  * Display text from a pipe in a scrolling window.
89  */
90 int
91 dialog_prgbox(const char *title,
92 	      const char *cprompt,
93 	      const char *command,
94 	      int height,
95 	      int width,
96 	      int pauseopt)
97 {
98     int code;
99     FILE *fp;
100 
101     fp = dlg_popen(command, "r");
102     if (fp == NULL)
103 	dlg_exiterr("pipe open failed: %s", command);
104 
105     code = dlg_progressbox(title, cprompt, height, width, pauseopt, fp);
106 
107     pclose(fp);
108 
109     return code;
110 }
111