1 /*
2 * Copyright 2009 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation. Sun designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Sun in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
22 * CA 95054 USA or visit www.sun.com if you need additional information or
23 * have any questions.
24 */
25
26 #include <sys/types.h>
27 #include <sys/stat.h>
28 #include <fcntl.h>
29 #include <stdlib.h>
30 #include <stdio.h>
31 #include <signal.h>
32 #include <dirent.h>
33 #include <string.h>
34 #include <errno.h>
35 #include <limits.h>
36 #include <unistd.h>
37
38 #include "processutil_md.h"
39
40 /*
41 * Utility used by j.l.ProcessBuilder (via UNIXProcess) to launch
42 * target commands. This (small) binary is launched via posix_spawn.
43 * It sets up the required environment for the target and then
44 * execs the target.
45 *
46 * argv[0] target command
47 * argv[1] working directory for command
48 * argv[2] = string containing fd numbers of pipes created in the parent
49 * in following order:
50 * stdinfd stdoutfd stderrfd statuspipe
51 * argv[3] = "1" redirect stderr to stdout, "0" don't
52 * argv[4]+ args to target
53 *
54 * The std{in,out,err} fds must be moved to their correct numbers first
55 * and the temporary pipe fd is also moved to position 3
56 * Then all fds above this are closed.
57 *
58 * Target environment (comprising null terminated strings)
59 * preceded by total byte length and number of strings
60 * are sent down the pipe. if these two initial vals are -1, then
61 * there is no environment.
62 *
63 * Response message sent up pipe to VM, if an error occurs:
64 *
65 * - Msg type (4 bytes)
66 * 1 = chdir error (detail in Field 1)
67 * 2 = exec error (detail in Field 1)
68 * 3 = target terminated (exit code in Field 1)
69 * - Field 1 (4 bytes)
70 *
71 * Assuming no error occured, the pipe will be set to close on exec
72 * and the parent will see EOF on its side of the pipe. This indicates
73 * a successful launch of the target.
74 */
75
76 static int stdinfd, stdoutfd, stderrfd, pipefd;
77
78 static void reply (int first, int second) {
79 int response[2];
80 response[0] = first;
81 response[1] = second;
82 write (pipefd, &response[0], sizeof(response));
83 }
84
85 void *jlup_xmalloc (void *env, int size) {
86 return malloc (size);
87 }
88
89 int main (int argc, char *argv[]) {
90
91 int err;
92 int child;
93 int envL; /* size of child environment */
94 int nenv; /* number of entries in child environment */
95 int flags, stderrIsPipe, redirectStderr;
96 const char **env, *ptr;
97 char name [256];
98 const char *nullptr = 0;
99 struct sigaction sa;
100 FILE *f;
101
102 jlup_initialize (NULL);
103 sa.sa_handler = SIG_DFL;
104 sigemptyset(&sa.sa_mask);
105 sa.sa_flags = SA_NOCLDSTOP | SA_RESTART;
106 sigaction(SIGCHLD, &sa, NULL);
107
108 if (sscanf (argv[2], "%d %d %d %d", &stdinfd, &stdoutfd, &stderrfd,
109 &pipefd) != 4) {
110 reply (2, 0);
111 exit (0);
112 }
113
114 if (*argv[1] != 0) {
115 err = chdir (argv[1]);
116 if (err != 0) {
117 reply (1, errno);
118 exit (0);
119 }
120 }
121
122 flags = atoi (argv[3]);
123 redirectStderr = flags & 0x1;
124 stderrIsPipe = flags & 0x2;
125
126 argv [3] = argv [0]; /* overwrite the args just handled */
127
128 jlup_moveDescriptor (stdinfd, 0);
129 jlup_moveDescriptor (stdoutfd, 1);
130 if (redirectStderr) {
131 if (stderrIsPipe) {
132 jlup_closeSafely (stderrfd);
133 }
134 dup2 (1, 2);
135 } else {
136 jlup_moveDescriptor (stderrfd, 2);
137 }
138 jlup_moveDescriptor (pipefd, 3);
139 pipefd = 3;
140
141 if (jlup_closeDescriptors(4) ==0) {
142 reply (2, errno);
143 exit (0);
144 }
145 /* read child's environment */
146 if (jlup_readFully(pipefd, &envL, sizeof(envL)) != sizeof(envL) ||
147 jlup_readFully(pipefd, &nenv, sizeof(nenv)) != sizeof(nenv)) {
148 reply (2, errno);
149 exit (0);
150 }
151
152 if (envL == -1) {
153 /* no environment */
154 env = 0;
155 } else if (envL != 0) {
156 /* at least one entry in environment */
157 ptr = malloc (envL);
158 if (jlup_readFully(pipefd, (void *)ptr, envL) != envL) {
159 reply (2, errno);
160 exit (0);
161 }
162 env = malloc (sizeof(char *) * nenv);
163 jlup_initVectorFromBlock (env, ptr, nenv);
164 } else {
165 /* empty environment */
166 env = &nullptr;
167 }
168 err = fcntl (pipefd, F_SETFD, FD_CLOEXEC);
169
170 jlup_execvpe ((const char * )argv[3], (const char * const*)&argv[3], env);
171 reply (2, errno);
172 exit (0);
173 return 0; /* keep compiler happy */
174 }