1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
|
/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include <string.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include "private/android_filesystem_config.h"
#include "cutils/log.h"
int parent(const char *tag, int parent_read) {
int status;
char buffer[4096];
int a = 0; // start index of unprocessed data
int b = 0; // end index of unprocessed data
int sz;
while ((sz = read(parent_read, &buffer[b], sizeof(buffer) - 1 - b)) > 0) {
sz += b;
// Log one line at a time
for (b = 0; b < sz; b++) {
if (buffer[b] == '\r') {
buffer[b] = '\0';
} else if (buffer[b] == '\n') {
buffer[b] = '\0';
LOG(LOG_INFO, tag, &buffer[a]);
a = b + 1;
}
}
if (a == 0 && b == sizeof(buffer) - 1) {
// buffer is full, flush
buffer[b] = '\0';
LOG(LOG_INFO, tag, &buffer[a]);
b = 0;
} else if (a != b) {
// Keep left-overs
b -= a;
memmove(buffer, &buffer[a], b);
a = 0;
} else {
a = 0;
b = 0;
}
}
// Flush remaining data
if (a != b) {
buffer[b] = '\0';
LOG(LOG_INFO, tag, &buffer[a]);
}
status = 0xAAAA;
if (wait(&status) != -1) { // Wait for child
if (WIFEXITED(status)) {
LOG(LOG_INFO, "logwrapper", "%s terminated by exit(%d)", tag,
WEXITSTATUS(status));
return WEXITSTATUS(status);
} else if (WIFSIGNALED(status))
LOG(LOG_INFO, "logwrapper", "%s terminated by signal %d", tag,
WTERMSIG(status));
else if (WIFSTOPPED(status))
LOG(LOG_INFO, "logwrapper", "%s stopped by signal %d", tag,
WSTOPSIG(status));
} else
LOG(LOG_INFO, "logwrapper", "%s wait() failed: %s (%d)", tag,
strerror(errno), errno);
return -EAGAIN;
}
void child(int argc, char* argv[]) {
// create null terminated argv_child array
char* argv_child[argc + 1];
memcpy(argv_child, argv, argc * sizeof(char *));
argv_child[argc] = NULL;
// XXX: PROTECT FROM VIKING KILLER
if (execv(argv_child[0], argv_child)) {
LOG(LOG_ERROR, "logwrapper",
"executing %s failed: %s", argv_child[0], strerror(errno));
exit(-1);
}
}
int logwrap(int argc, char* argv[], pid_t *childPid)
{
pid_t pid;
int parent_ptty;
int child_ptty;
char *child_devname = NULL;
/* Use ptty instead of socketpair so that STDOUT is not buffered */
parent_ptty = open("/dev/ptmx", O_RDWR);
if (parent_ptty < 0) {
LOG(LOG_ERROR, "logwrapper", "Cannot create parent ptty");
return -errno;
}
if (grantpt(parent_ptty) || unlockpt(parent_ptty) ||
((child_devname = (char*)ptsname(parent_ptty)) == 0)) {
LOG(LOG_ERROR, "logwrapper", "Problem with /dev/ptmx");
return -1;
}
pid = fork();
if (pid < 0) {
LOG(LOG_ERROR, "logwrapper", "Failed to fork");
return -errno;
} else if (pid == 0) {
child_ptty = open(child_devname, O_RDWR);
if (child_ptty < 0) {
LOG(LOG_ERROR, "logwrapper", "Problem with child ptty");
return -errno;
}
// redirect stdout and stderr
close(parent_ptty);
dup2(child_ptty, 1);
dup2(child_ptty, 2);
close(child_ptty);
child(argc, argv);
} else {
return parent(argv[0], parent_ptty);
}
return 0;
}
|
