1/*
2 * Copyright (c) 2013, Oracle and/or its affiliates. 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.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26#include <errno.h>
27#include <fcntl.h>
28#include <stdio.h>
29#include <stdlib.h>
30#include <unistd.h>
31#include <sys/types.h>
32#include <sys/stat.h>
33
34#include "childproc.h"
35
36extern int errno;
37
38#define ALLOC(X,Y) { \
39    void *mptr; \
40    mptr = malloc (Y); \
41    if (mptr == 0) { \
42        error (fdout, ERR_MALLOC); \
43    } \
44    X = mptr; \
45}
46
47#define ERR_MALLOC 1
48#define ERR_PIPE 2
49#define ERR_ARGS 3
50
51void error (int fd, int err) {
52    write (fd, &err, sizeof(err));
53    exit (1);
54}
55
56void shutItDown() {
57    fprintf(stdout, "This command is not for general use and should ");
58    fprintf(stdout, "only be run as the result of a call to\n");
59    fprintf(stdout, "ProcessBuilder.start() or Runtime.exec() in a java ");
60    fprintf(stdout, "application\n");
61    _exit(1);
62}
63
64/*
65 * read the following off the pipefd
66 * - the ChildStuff struct
67 * - the SpawnInfo struct
68 * - the data strings for fields in ChildStuff
69 */
70void initChildStuff (int fdin, int fdout, ChildStuff *c) {
71    int n;
72    int argvBytes, nargv, envvBytes, nenvv;
73    int dirlen;
74    char *buf;
75    SpawnInfo sp;
76    int bufsize, offset=0;
77    int magic;
78    int res;
79
80    res = readFully (fdin, &magic, sizeof(magic));
81    if (res != 4 || magic != magicNumber()) {
82        error (fdout, ERR_PIPE);
83    }
84
85    if (readFully (fdin, c, sizeof(*c)) == -1) {
86        error (fdout, ERR_PIPE);
87    }
88
89    if (readFully (fdin, &sp, sizeof(sp)) == -1) {
90        error (fdout, ERR_PIPE);
91    }
92
93    bufsize = sp.argvBytes + sp.envvBytes +
94              sp.dirlen + sp.parentPathvBytes;
95
96    ALLOC(buf, bufsize);
97
98    if (readFully (fdin, buf, bufsize) == -1) {
99        error (fdout, ERR_PIPE);
100    }
101
102    /* Initialize argv[] */
103    ALLOC(c->argv, sizeof(char *) * sp.nargv);
104    initVectorFromBlock (c->argv, buf+offset, sp.nargv-1);
105    offset += sp.argvBytes;
106
107    /* Initialize envv[] */
108    if (sp.nenvv == 0) {
109        c->envv = 0;
110    } else {
111        ALLOC(c->envv, sizeof(char *) * sp.nenvv);
112        initVectorFromBlock (c->envv, buf+offset, sp.nenvv-1);
113        offset += sp.envvBytes;
114    }
115
116    /* Initialize pdir */
117    if (sp.dirlen == 0) {
118        c->pdir = 0;
119    } else {
120        c->pdir = buf+offset;
121        offset += sp.dirlen;
122    }
123
124    /* Initialize parentPathv[] */
125    ALLOC(parentPathv, sizeof (char *) * sp.nparentPathv)
126    initVectorFromBlock ((const char**)parentPathv, buf+offset, sp.nparentPathv-1);
127    offset += sp.parentPathvBytes;
128}
129
130int main(int argc, char *argv[]) {
131    ChildStuff c;
132    int t;
133    struct stat buf;
134    /* argv[0] contains the fd number to read all the child info */
135    int r, fdin, fdout;
136
137    r = sscanf (argv[argc-1], "%d:%d", &fdin, &fdout);
138    if (r == 2 && fcntl(fdin, F_GETFD) != -1) {
139        fstat(fdin, &buf);
140        if (!S_ISFIFO(buf.st_mode))
141            shutItDown();
142    } else {
143        shutItDown();
144    }
145    initChildStuff (fdin, fdout, &c);
146
147    childProcess (&c);
148    return 0; /* NOT REACHED */
149}
150