source: mainline/uspace/app/getterm/getterm.c@ 1c635d6

lfn serial ticket/834-toolchain-update topic/msim-upgrade topic/simplify-dev-export
Last change on this file since 1c635d6 was 1c635d6, checked in by Martin Sucha <sucha14@…>, 11 years ago

Do not hold a task's return value after it has disconnected.

Holding the task's return value meant that if nobody waited
for task's result, it polluted NS's memory. This was apparently
done because of a race between spawning a task and waiting for it.

We solve this problem in another way: ns discards the return value
as soon as the task disconnects from it. This typically happens
when the task finishes its execution. In order to avoid the race,
we send the wait request to ns while spawning the task (i.e. when
we talk to the loader), but before we allow the loaded program
to run.

Fixes #132

  • Property mode set to 100644
File size: 4.3 KB
Line 
1/*
2 * Copyright (c) 2009 Martin Decky
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 *
9 * - Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * - Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 * - The name of the author may not be used to endorse or promote products
15 * derived from this software without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27 */
28
29/** @addtogroup getterm GetTerm
30 * @brief Console initialization task.
31 * @{
32 */
33/**
34 * @file
35 */
36
37#include <sys/types.h>
38#include <fcntl.h>
39#include <unistd.h>
40#include <stdio.h>
41#include <task.h>
42#include <str_error.h>
43#include <errno.h>
44#include <loc.h>
45#include "version.h"
46#include "welcome.h"
47
48#define APP_NAME "getterm"
49
50static void usage(void)
51{
52 printf("Usage: %s <terminal> <locfs> [--msg] [--wait] -- "
53 "<command> [<arguments...>]\n", APP_NAME);
54 printf(" <terminal> Terminal device\n");
55 printf(" <locfs> Mount point of locfs\n");
56 printf(" --msg Print welcome message\n");
57 printf(" --wait Wait for the terminal to be ready\n");
58}
59
60static void reopen(FILE **stream, int fd, const char *path, int flags,
61 const char *mode)
62{
63 if (fclose(*stream))
64 return;
65
66 *stream = NULL;
67
68 int oldfd = open(path, flags);
69 if (oldfd < 0)
70 return;
71
72 if (oldfd != fd) {
73 if (dup2(oldfd, fd) != fd)
74 return;
75
76 if (close(oldfd))
77 return;
78 }
79
80 *stream = fdopen(fd, mode);
81}
82
83int main(int argc, char *argv[])
84{
85 argv++;
86 argc--;
87 if (argc < 4) {
88 usage();
89 return 1;
90 }
91
92 char *term = *argv;
93 argv++;
94 argc--;
95
96 char *locfs = *argv;
97 argv++;
98 argc--;
99
100 bool print_msg = false;
101 bool wait = false;
102
103 while ((argc > 0) && (str_cmp(*argv, "--") != 0)) {
104 if (str_cmp(*argv, "--msg") == 0) {
105 print_msg = true;
106 } else if (str_cmp(*argv, "--wait") == 0) {
107 wait = true;
108 } else {
109 usage();
110 return 2;
111 }
112
113 argv++;
114 argc--;
115 }
116
117 if (argc < 1) {
118 usage();
119 return 3;
120 }
121
122 /* Skip "--" */
123 argv++;
124 argc--;
125
126 char *cmd = *argv;
127 char **args = argv;
128
129 if (wait) {
130 /* Wait for the terminal service to be ready */
131 service_id_t service_id;
132 int rc = loc_service_get_id(term, &service_id, IPC_FLAG_BLOCKING);
133 if (rc != EOK) {
134 printf("%s: Error waiting on %s (%s)\n", APP_NAME, term,
135 str_error(rc));
136 return rc;
137 }
138 }
139
140 char term_node[LOC_NAME_MAXLEN];
141 snprintf(term_node, LOC_NAME_MAXLEN, "%s/%s", locfs, term);
142
143 reopen(&stdin, 0, term_node, O_RDONLY, "r");
144 reopen(&stdout, 1, term_node, O_WRONLY, "w");
145 reopen(&stderr, 2, term_node, O_WRONLY, "w");
146
147 if (stdin == NULL)
148 return 4;
149
150 if (stdout == NULL)
151 return 5;
152
153 if (stderr == NULL)
154 return 6;
155
156 /*
157 * FIXME: fdopen() should actually detect that we are opening a console
158 * and it should set line-buffering mode automatically.
159 */
160 setvbuf(stdout, NULL, _IOLBF, BUFSIZ);
161
162 version_print(term);
163 if (print_msg)
164 welcome_msg_print();
165
166 task_id_t id;
167 task_wait_t twait;
168
169 int rc = task_spawnv(&id, &twait, cmd, (const char * const *) args);
170 if (rc != EOK) {
171 printf("%s: Error spawning %s (%s)\n", APP_NAME, cmd,
172 str_error(rc));
173 return rc;
174 }
175
176 task_exit_t texit;
177 int retval;
178 rc = task_wait(&twait, &texit, &retval);
179 if (rc != EOK) {
180 printf("%s: Error waiting for %s (%s)\n", APP_NAME, cmd,
181 str_error(rc));
182 return rc;
183 }
184
185 return 0;
186}
187
188/** @}
189 */
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