blob: c96426f61be67db887adaceae45f007d154871cd [file] [log] [blame]
San Mehat49e2bce2009-10-12 16:29:01 -07001/*
2 * Copyright (C) 2008 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <string.h>
18#include <sys/types.h>
19#include <sys/wait.h>
20#include <stdio.h>
21#include <stdlib.h>
22#include <unistd.h>
23#include <errno.h>
24#include <fcntl.h>
25
26#include "private/android_filesystem_config.h"
27#include "cutils/log.h"
28
29int parent(const char *tag, int parent_read) {
30 int status;
31 char buffer[4096];
32
33 int a = 0; // start index of unprocessed data
34 int b = 0; // end index of unprocessed data
35 int sz;
36 while ((sz = read(parent_read, &buffer[b], sizeof(buffer) - 1 - b)) > 0) {
37
38 sz += b;
39 // Log one line at a time
40 for (b = 0; b < sz; b++) {
41 if (buffer[b] == '\r') {
42 buffer[b] = '\0';
43 } else if (buffer[b] == '\n') {
44 buffer[b] = '\0';
45
46 LOG(LOG_INFO, tag, "%s", &buffer[a]);
47 a = b + 1;
48 }
49 }
50
51 if (a == 0 && b == sizeof(buffer) - 1) {
52 // buffer is full, flush
53 buffer[b] = '\0';
54 LOG(LOG_INFO, tag, &buffer[a]);
55 b = 0;
56 } else if (a != b) {
57 // Keep left-overs
58 b -= a;
59 memmove(buffer, &buffer[a], b);
60 a = 0;
61 } else {
62 a = 0;
63 b = 0;
64 }
65
66 }
67 // Flush remaining data
68 if (a != b) {
69 buffer[b] = '\0';
70 LOG(LOG_INFO, tag, &buffer[a]);
71 }
72 status = 0xAAAA;
73 if (wait(&status) != -1) { // Wait for child
74 if (WIFEXITED(status)) {
75 LOG(LOG_INFO, "logwrapper", "%s terminated by exit(%d)", tag,
76 WEXITSTATUS(status));
77 return WEXITSTATUS(status);
78 } else if (WIFSIGNALED(status))
79 LOG(LOG_INFO, "logwrapper", "%s terminated by signal %d", tag,
80 WTERMSIG(status));
81 else if (WIFSTOPPED(status))
82 LOG(LOG_INFO, "logwrapper", "%s stopped by signal %d", tag,
83 WSTOPSIG(status));
84 } else
85 LOG(LOG_INFO, "logwrapper", "%s wait() failed: %s (%d)", tag,
86 strerror(errno), errno);
87 return -EAGAIN;
88}
89
90void child(int argc, const char**argv) {
91 // create null terminated argv_child array
92 char* argv_child[argc + 1];
93 memcpy(argv_child, argv, argc * sizeof(char *));
94 argv_child[argc] = NULL;
95
96 // XXX: PROTECT FROM VIKING KILLER
97 if (execv(argv_child[0], argv_child)) {
98 LOG(LOG_ERROR, "logwrapper",
99 "executing %s failed: %s", argv_child[0], strerror(errno));
100 exit(-1);
101 }
102}
103
104int logwrap(int argc, const char* argv[], int background)
105{
106 pid_t pid;
107
108 int parent_ptty;
109 int child_ptty;
110 char *child_devname = NULL;
111
112 /* Use ptty instead of socketpair so that STDOUT is not buffered */
113 parent_ptty = open("/dev/ptmx", O_RDWR);
114 if (parent_ptty < 0) {
115 LOG(LOG_ERROR, "logwrapper", "Cannot create parent ptty");
116 return -errno;
117 }
118
119 if (grantpt(parent_ptty) || unlockpt(parent_ptty) ||
120 ((child_devname = (char*)ptsname(parent_ptty)) == 0)) {
121 LOG(LOG_ERROR, "logwrapper", "Problem with /dev/ptmx");
122 return -1;
123 }
124
125 pid = fork();
126 if (pid < 0) {
127 LOG(LOG_ERROR, "logwrapper", "Failed to fork");
128 return -errno;
129 } else if (pid == 0) {
130 child_ptty = open(child_devname, O_RDWR);
131 if (child_ptty < 0) {
132 LOG(LOG_ERROR, "logwrapper", "Problem with child ptty");
133 return -errno;
134 }
135
136 // redirect stdout and stderr
137 close(parent_ptty);
138 dup2(child_ptty, 1);
139 dup2(child_ptty, 2);
140 close(child_ptty);
141
142 if (background) {
143 int fd = open("/dev/cpuctl/bg_non_interactive/tasks", O_WRONLY);
144
145 if (fd >=0 ) {
146 char text[64];
147
148 sprintf(text, "%d", getpid());
149 if (write(fd, text, strlen(text)) < 0) {
150 LOG(LOG_WARN, "logwrapper",
151 "Unable to background process (%s)", strerror(errno));
152 close(fd);
153 }
154 close(fd);
155 } else {
156 LOG(LOG_WARN, "logwrapper",
157 "Unable to background process (%s)", strerror(errno));
158 }
159 }
160
161 child(argc, argv);
162 } else {
163 return parent(argv[0], parent_ptty);
164 }
165
166 return 0;
167}