platform_hardware_libhardware/include/hardware/qemu_pipe.h
David 'Digit' Turner 33fddf0ca9 emulator: Add <hardware/qemu_pipe.h> header
This header is required by our GLES emulation guest code to be able
to access the emulator services provided through the /dev/qemu_pipe
special device.

Change-Id: Ia9782256048d7340237f3e1d18d7452dd815e561
2011-09-16 17:11:49 +02:00

91 lines
2.7 KiB
C

/*
* Copyright (C) 2011 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_QEMU_PIPE_H
#define ANDROID_INCLUDE_HARDWARE_QEMU_PIPE_H
#include <sys/cdefs.h>
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <pthread.h> /* for pthread_once() */
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#ifndef D
# define D(...) do{}while(0)
#endif
/* Try to open a new Qemu fast-pipe. This function returns a file descriptor
* that can be used to communicate with a named service managed by the
* emulator.
*
* This file descriptor can be used as a standard pipe/socket descriptor.
*
* 'pipeName' is the name of the emulator service you want to connect to.
* E.g. 'opengles' or 'camera'.
*
* On success, return a valid file descriptor
* Returns -1 on error, and errno gives the error code, e.g.:
*
* EINVAL -> unknown/unsupported pipeName
* ENOSYS -> fast pipes not available in this system.
*
* ENOSYS should never happen, except if you're trying to run within a
* misconfigured emulator.
*
* You should be able to open several pipes to the same pipe service,
* except for a few special cases (e.g. GSM modem), where EBUSY will be
* returned if more than one client tries to connect to it.
*/
static __inline__ int
qemu_pipe_open(const char* pipeName)
{
char buff[256];
int buffLen;
int fd, ret;
if (pipeName == NULL || pipeName[0] == '\0') {
errno = EINVAL;
return -1;
}
snprintf(buff, sizeof buff, "pipe:%s", pipeName);
fd = open("/dev/qemu_pipe", O_RDWR);
if (fd < 0) {
D("%s: Could not open /dev/qemu_pipe: %s", __FUNCTION__, strerror(errno));
//errno = ENOSYS;
return -1;
}
buffLen = strlen(buff);
ret = TEMP_FAILURE_RETRY(write(fd, buff, buffLen+1));
if (ret != buffLen+1) {
D("%s: Could not connect to %s pipe service: %s", __FUNCTION__, pipeName, strerror(errno));
if (ret == 0) {
errno = ECONNRESET;
} else if (ret > 0) {
errno = EINVAL;
}
return -1;
}
return fd;
}
#endif /* ANDROID_INCLUDE_HARDWARE_QEMUD_PIPE_H */