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/* See LICENSE file for copyright and license details. */
#include "stream.h"
#include "util.h"
#include <alloca.h>
#include <string.h>
USAGE("[-L] (file (end-point | 'end')) ...")
int
main(int argc, char *argv[])
{
struct stream stream;
size_t *ends, i, parts, ptr, end, n;
char *to_end;
FILE *fp;
int fd, unknown_length = 0;
ARGBEGIN {
case 'L':
unknown_length = 1;
break;
default:
usage();
} ARGEND;
if (argc % 2 || !argc)
usage();
eopen_stream(&stream, NULL);
echeck_dimensions(&stream, WIDTH | HEIGHT | LENGTH, NULL);
parts = (size_t)argc / 2;
ends = alloca(parts * sizeof(*ends));
to_end = alloca(parts);
for (i = 0; i < parts; i++) {
to_end[i] = 0;
if (!strcmp(argv[i * 2 + 1], "end")) {
ends[i] = unknown_length ? SIZE_MAX : stream.frames;
to_end[i] = 1;
} else if (tozu(argv[i * 2 + 1], 0, SIZE_MAX, ends + i)) {
eprintf("the end point must be an integer in [0, %zu]\n", SIZE_MAX);
}
if (i && ends[i] <= ends[i - 1])
eprintf("the end points must be in strictly ascending order\n");
if (!unknown_length && ends[i] > stream.frames)
eprintf("frame %zu is beyond the end of the video\n", ends[i]);
}
ptr = 0;
for (i = 0; i < parts; i++) {
fd = eopen(argv[i * 2], O_WRONLY | O_CREAT | O_TRUNC, 0666);
fp = fdopen(fd, "wb");
if (!fp)
eprintf("fdopen %s:", argv[i * 2]);
stream.frames = ends[i] - (i ? ends[i - 1] : 0);
fprint_stream_head(fp, &stream);
efflush(fp, argv[i * 2]);
for (end = to_end[i] ? SIZE_MAX : ends[i] * stream.frame_size; ptr < end; ptr += n) {
n = end - ptr;
if (stream.ptr) {
n = MIN(stream.ptr, n);
ewriteall(fd, stream.buf, n, argv[i * 2]);
memmove(stream.buf, stream.buf + n, stream.ptr -= n);
} else if ((n = eread_stream(&stream, n))) {
ewriteall(fd, stream.buf, n, argv[i * 2]);
stream.ptr = 0;
} else if (ptr % stream.frame_size) {
eprintf("%s: incomplete frame\n", stream.file);
} else if (!unknown_length || !to_end[i]) {
eprintf("%s: file is shorter than expected\n", stream.file);
} else {
break;
}
}
if (fclose(fp))
eprintf("%s:", argv[i * 2]);
close(fd);
}
return 0;
}
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