46 lines
696 B
C++
46 lines
696 B
C++
#include <fcntl.h>
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#include <string.h>
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#include <sys/framebuffer.h>
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#include <sys/mman.h>
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int main()
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{
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int fd = open("/dev/fb0", O_RDWR);
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if (fd == -1)
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{
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perror("open");
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return 1;
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}
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framebuffer_info_t fb_info;
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if (pread(fd, &fb_info, sizeof(fb_info), -1) == -1)
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{
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perror("read");
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return 1;
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}
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size_t fb_size = fb_info.width * fb_info.height * fb_info.bpp / 8;
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void* addr = mmap(nullptr, fb_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
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if (addr == MAP_FAILED)
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{
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perror("mmap");
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return 1;
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}
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memset(addr, 0xFF, fb_size);
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if (msync(addr, fb_size, MS_SYNC) == -1)
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{
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perror("msync");
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return 1;
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}
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sleep(4);
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munmap(addr, fb_size);
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close(fd);
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return 0;
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}
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