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/* See LICENSE file for copyright and license details. */
#include "arg.h"
#include "stream.h"
#include "util.h"
#include <fcntl.h>
#include <limits.h>
#include <stdint.h>
#include <unistd.h>
static void
usage(void)
{
eprintf("usage: %s file\n", argv0);
}
int
main(int argc, char *argv[])
{
struct stream stream;
size_t frame_size, ptr, end, n, ptw;
ssize_t r;
char buf[BUFSIZ];
ARGBEGIN {
default:
usage();
} ARGEND;
if (argc != 1)
usage();
stream.file = argv[1];
stream.fd = open(stream.file, O_RDONLY);
if (stream.fd < 0)
eprintf("open %s:", stream.file);
einit_stream(&stream);
fprint_stream_head(stdout, &stream);
fflush(stdout);
if (ferror(stdout))
eprintf("<stdout>:");
if (stream.width > SIZE_MAX / stream.height)
eprintf("%s: video is too large\n", stream.file);
frame_size = stream.width * stream.height;
if (stream.frames > SSIZE_MAX / frame_size)
eprintf("%s: video is too large\n", stream.file);
posix_fadvise(stream.fd, 0, 0, POSIX_FADV_RANDOM);
while (stream.frames--) {
ptr = stream.frames * frame_size;
end = ptr + frame_size;
while (ptr < end) {
r = pread(stream.fd, buf, sizeof(buf), ptr);
if (r < 0)
eprintf("pread %s:", stream.file);
else if (r == 0)
eprintf("%s: file is shorter than expected", stream.file);
ptr += n = (size_t)r;
for (ptw = 0; ptw < n;) {
r = write(STDOUT_FILENO, buf + ptw, n - ptw);
if (r < 0)
eprintf("write <stdout>:");
ptw += (size_t)r;
}
}
}
close(stream.fd);
return 0;
}
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