Files
android_development/tools/emulator/system/libqemu/libqemu.c
David 'Digit' Turner e1eea50214 emulator: Add libqemu static library to implement qemu pipes.
See hardware/libhardware/include/hardware/qemu_pipe.h for the API
implemented by the library. It enables very fast reads/writes between
the guest system and specific emulator services.

Define BUILD_LIBQEMU_TESTS=true in your environment to build the
test programs (a simple host ping-pong server, and a benchmark
guest program).

You can invoke them with:

1/ Testing TCP pipes:

   host:  test-libqemu-1 -tcp 8012
   guest: test-libqemu-2 -pipe tcp:8012

Alternatively

   guest: su
          test-libqemu-2 -tcp 8012

2/ Testing Unix pipes:

   host:  test-libqemu-1 -unix /tmp/libqemu-socket
   guest: test-libqemu-2 -pipe unix:/tmp/libqemu-socket

3/ Testing internal pingpong server (within the emulator)

   host:   /* nothing to do */
   guest:  test-libqemu-2

Change-Id: Ib50fc9cbee6b5f4581baca97412d6f69d4f84860
2011-04-28 16:48:15 +02:00

82 lines
2.2 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.
*/
/* Set to 1 to enable debugging */
#define DEBUG 0
#if DEBUG >= 1
# define D(...) fprintf(stderr,"libqemud:" __VA_ARGS__), fprintf(stderr, "\n")
#endif
#include <unistd.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <hardware/qemud.h>
#include <hardware/qemu_pipe.h>
#include <pthread.h> /* for pthread_once() */
#include <stdlib.h>
#include <stdio.h>
/* Used for debugging */
#ifndef D
# define D(...) do{}while(0)
#endif
/* Try to open a qemud pipe, 'pipeName' must be a generic pipe service
* name (e.g. "opengles" or "camera"). The emulator will be in charge of
* connecting the corresponding pipe/client to an internal service or an
* external socket, these details are hidden from the caller.
*
* Return a new QemuPipe pointer, or NULL in case of error
*/
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;
}