platform_system_core/adb/framebuffer_service.c

70 lines
1.7 KiB
C

/*
* Copyright (C) 2007 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 <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <string.h>
#include <fcntl.h>
#include "fdevent.h"
#include "adb.h"
#include <linux/fb.h>
#include <sys/ioctl.h>
#include <sys/mman.h>
/* TODO:
** - grab the current buffer, not the first buffer
** - sync with vsync to avoid tearing
*/
void framebuffer_service(int fd, void *cookie)
{
struct fb_var_screeninfo vinfo;
int fb;
void *ptr = MAP_FAILED;
char x;
unsigned fbinfo[4];
fb = open("/dev/graphics/fb0", O_RDONLY);
if(fb < 0) goto done;
if(ioctl(fb, FBIOGET_VSCREENINFO, &vinfo) < 0) goto done;
fcntl(fb, F_SETFD, FD_CLOEXEC);
fbinfo[0] = 16;
fbinfo[1] = vinfo.xres * vinfo.yres * 2;
fbinfo[2] = vinfo.xres;
fbinfo[3] = vinfo.yres;
ptr = mmap(0, fbinfo[1], PROT_READ, MAP_SHARED, fb, 0);
if(ptr == MAP_FAILED) goto done;
if(writex(fd, fbinfo, sizeof(unsigned) * 4)) goto done;
for(;;) {
if(readx(fd, &x, 1)) goto done;
if(writex(fd, ptr, fbinfo[1])) goto done;
}
done:
if(ptr != MAP_FAILED) munmap(ptr, fbinfo[1]);
if(fb >= 0) close(fb);
close(fd);
}