Add blind-translate and fix errors

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 184 insertions, 0 deletions

diff --git a/src/blind-translate.c b/src/blind-translate.c
new file mode 100644
index 0000000..95b8dab
--- /dev/null
+++ b/src/blind-translate.c
@@ -0,0 +1,184 @@
+/* See LICENSE file for copyright and license details. */
+#include "stream.h"
+#include "util.h"
+
+#include <fcntl.h>
+#include <inttypes.h>
+#include <math.h>
+#include <string.h>
+#include <unistd.h>
+
+USAGE("[-wp] translation-stream")
+
+static int invtrans = 0;
+static char zeroes[BUFSIZ];
+
+static void*
+next_pixel(struct stream *stream, size_t *ptr)
+{
+	void *ret;
+	if (*ptr + stream->pixel_size >= stream->ptr) {
+		memmove(stream->buf, stream->buf + *ptr, stream->ptr -= *ptr);
+		*ptr = 0;
+		while (stream->ptr < stream->pixel_size)
+			if (!eread_stream(stream, SIZE_MAX))
+				return NULL;
+	}
+	ret = stream->buf + *ptr;
+	*ptr += stream->pixel_size;
+	return ret;
+}
+
+static int
+process_frame(struct stream *stream, char *buf, size_t n,
+	      size_t above, size_t below, size_t left, size_t right)
+{
+#define ZEROES(N) ewritezeroes(STDOUT_FILENO, zeroes, sizeof(zeroes), N, "<stdout>")
+
+	size_t i, w = n - left - right;
+	int first = 1;
+
+	if (!eread_row(stream, buf, n))
+		return 0;
+
+	for (i = 0; i < above; i++)
+		ZEROES(n);
+	for (i = 0; i < below; i++, first = 0)
+		if (!first && !eread_row(stream, buf, n))
+			goto eof;
+
+	for (i = above + below; i < stream->height; i++, first = 0) {
+		if (!first && !eread_row(stream, buf, n))
+			goto eof;
+		ZEROES((size_t)left);
+		ewriteall(STDOUT_FILENO, buf + right, w, "<stdout>");
+		ZEROES((size_t)right);
+	}
+
+	for (i = 0; i < below; i++)
+		ZEROES(n);
+	for (i = 0; i < above; i++, first = 0)
+		if (!first && !eread_row(stream, buf, n))
+			goto eof;
+
+	return 1;
+eof:
+	eprintf("%s: file is shorter than expected\n", stream->file);
+	return 0;
+
+#undef ZEROES
+}
+
+static void
+process(struct stream *stream, struct stream *trstream)
+{
+	char *buf;
+	size_t n, p = 0;
+	double *trans;
+	ssize_t trx = 0, try = 0;
+	size_t above = 0, below = 0, left = 0, right = 0;
+
+	memset(zeroes, 0, sizeof(zeroes));
+
+	if (!check_frame_size(stream->width, 1, stream->pixel_size))
+		eprintf("%s: video frame is too wide\n", stream->file);
+	n = stream->width * stream->pixel_size;
+	buf = emalloc(n);
+
+	do {
+		if ((trans = next_pixel(trstream, &p))) {
+			trx = (ssize_t)round(invtrans ? -trans[0] : trans[0]);
+			try = (ssize_t)round(invtrans ? -trans[1] : trans[1]);
+
+			above =  try > 0 ? (size_t)try  : 0;
+			below =  try < 0 ? (size_t)-try : 0;
+			left  = (trx > 0 ? (size_t)trx  : 0) * stream->pixel_size;
+			right = (trx < 0 ? (size_t)-trx : 0) * stream->pixel_size;
+
+			above = above < stream->height ? above : stream->height;
+			below = below < stream->height ? below : stream->height;
+			left  = left  < n ? left  : n;
+			right = right < n ? right : n;
+		}
+	} while (process_frame(stream, buf, n, above, below, left, right));
+
+	free(buf);
+}
+
+static void
+process_wrap(struct stream *stream, struct stream *trstream)
+{
+	char *buf, *row;
+	size_t n, rown, p = 0;
+	double *trans;
+	ssize_t trx = 0, try = 0, py;
+	size_t off = 0, y;
+
+	echeck_frame_size(stream->width, stream->height, stream->pixel_size, 0, "<stdin>");
+	n = stream->height * (rown = stream->width * stream->pixel_size);
+	buf = emalloc(n);
+
+	while (eread_frame(stream, buf, n)) {
+		if ((trans = next_pixel(trstream, &p))) {
+			trx = (ssize_t)round(invtrans ? -trans[0] : trans[0]);
+			try = (ssize_t)round(invtrans ? -trans[1] : trans[1]);
+			trx %= (ssize_t)stream->width;
+			if (trx < 0)
+				trx += (ssize_t)stream->width;
+			off = (stream->width - (size_t)trx) % stream->width;
+			off = off * stream->pixel_size;
+		}
+
+		for (y = 0; y < stream->height; y++) {
+			py = ((ssize_t)y - try) % (ssize_t)stream->height;
+			if (py < 0)
+				py += (ssize_t)stream->height;
+			row = buf + (size_t)py * rown;
+			ewriteall(STDOUT_FILENO, row + off, rown - off, "<stdout>");
+			ewriteall(STDOUT_FILENO, row, off, "<stdout>");
+		}
+	}
+
+	free(buf);
+}
+
+int
+main(int argc, char *argv[])
+{
+	struct stream stream;
+	struct stream trstream;
+	int wrap = 0;
+
+	ARGBEGIN {
+	case 'w':
+		wrap = 1;
+		break;
+	case 'p':
+		invtrans = 1;
+		break;
+	} ARGEND;
+
+	if (argc != 1)
+		usage();
+
+	stream.file = "<stdin>";
+	stream.fd = STDIN_FILENO;
+	einit_stream(&stream);
+	fprint_stream_head(stdout, &stream);
+	efflush(stdout, "<stdout>");
+
+	trstream.file = argv[0];
+	trstream.fd = eopen(trstream.file, O_RDONLY);
+	einit_stream(&trstream);
+
+	if (trstream.width != 1 || trstream.height != 1)
+		eprintf("translation-stream does not have 1x1 geometry\n");
+
+	if (strcmp(trstream.pixfmt, "xyza"))
+		eprintf("pixel format of translation-stream %s "
+			"is not supported, try xyza\n", trstream.pixfmt);
+
+	(wrap ? process_wrap : process)(&stream, &trstream);
+	close(trstream.fd);
+	return 0;
+}