platform_hardware_libhardware/include/hardware/qemud.h
2009-03-18 17:39:47 -07:00

144 lines
3.7 KiB
C

/*
* 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.
*/
#ifndef ANDROID_INCLUDE_HARDWARE_QEMUD_H
#define ANDROID_INCLUDE_HARDWARE_QEMUD_H
#include <cutils/sockets.h>
/* the following is helper code that is used by the QEMU-specific
* hardware HAL modules to communicate with the emulator program
* through the 'qemud' multiplexing daemon.
*
* see the documentation comments for details in
* development/emulator/qemud/qemud.c
*
* all definitions here are built into the HAL module to avoid
* having to write a tiny shared library for this.
*/
/* we expect the D macro to be defined to a function macro
* that sends its formatted string argument(s) to the log.
* If not, ignore the traces.
*/
#ifndef D
# define D(...) ((void)0)
#endif
static __inline__ int
qemud_fd_write(int fd, const void* buff, int len)
{
int len2;
do {
len2 = write(fd, buff, len);
} while (len2 < 0 && errno == EINTR);
return len2;
}
static __inline__ int
qemud_fd_read(int fd, void* buff, int len)
{
int len2;
do {
len2 = read(fd, buff, len);
} while (len2 < 0 && errno == EINTR);
return len2;
}
static __inline__ int
qemud_channel_open(const char* name)
{
int fd;
int namelen = strlen(name);
char answer[2];
/* connect to qemud control socket */
fd = socket_local_client( "qemud",
ANDROID_SOCKET_NAMESPACE_RESERVED,
SOCK_STREAM );
if (fd < 0) {
D("no qemud control socket: %s", strerror(errno));
return -1;
}
/* send service name to connect */
if (qemud_fd_write(fd, name, namelen) != namelen) {
D("can't send service name to qemud: %s",
strerror(errno));
close(fd);
return -1;
}
/* read answer from daemon */
if (qemud_fd_read(fd, answer, 2) != 2 ||
answer[0] != 'O' || answer[1] != 'K') {
D("cant' connect to %s service through qemud", name);
close(fd);
return -1;
}
return fd;
}
static __inline__ int
qemud_channel_send(int fd, const void* msg, int msglen)
{
char header[5];
if (msglen < 0)
msglen = strlen((const char*)msg);
if (msglen == 0)
return 0;
snprintf(header, sizeof header, "%04x", msglen);
if (qemud_fd_write(fd, header, 4) != 4) {
D("can't write qemud frame header: %s", strerror(errno));
return -1;
}
if (qemud_fd_write(fd, msg, msglen) != msglen) {
D("can4t write qemud frame payload: %s", strerror(errno));
return -1;
}
return 0;
}
static __inline__ int
qemud_channel_recv(int fd, void* msg, int msgsize)
{
char header[5];
int size, avail;
if (qemud_fd_read(fd, header, 4) != 4) {
D("can't read qemud frame header: %s", strerror(errno));
return -1;
}
header[4] = 0;
if (sscanf(header, "%04x", &size) != 1) {
D("malformed qemud frame header: '%.*s'", 4, header);
return -1;
}
if (size > msgsize)
return -1;
if (qemud_fd_read(fd, msg, size) != size) {
D("can't read qemud frame payload: %s", strerror(errno));
return -1;
}
return size;
}
#endif /* ANDROID_INCLUDE_HARDWARE_QEMUD_H */