Generate kernel matcher data

This application generates the matcher tables of the tracking
library in the linux kernel.

Signed-off-by: Henrik Rydberg <rydberg@euromail.se>

3 files changed, 163 insertions, 1 deletions

diff --git a/.gitignore b/.gitignore
index fbe141a..f39d5b3 100644
--- a/.gitignore
+++ b/.gitignore
@@ -78,4 +78,5 @@ core
 test/mtdev-test
 test/mtdev-mapgen
 test/mtdev-matching
+test/mtdev-kernel
 patches
diff --git a/test/Makefile.am b/test/Makefile.am
index 12df79a..0cdd859 100644
--- a/test/Makefile.am
+++ b/test/Makefile.am
@@ -1,4 +1,4 @@
-noinst_PROGRAMS = mtdev-mapgen mtdev-matching
+noinst_PROGRAMS = mtdev-mapgen mtdev-matching mtdev-kernel
 bin_PROGRAMS = mtdev-test
 
 INCLUDES=-I$(top_srcdir)/include/
@@ -10,3 +10,6 @@ mtdev_matching_LDFLAGS = -L$(top_builddir)/src/.libs/ -lmtdev
 
 mtdev_test_SOURCES = mtdev-test.c
 mtdev_test_LDFLAGS = -lmtdev -L$(top_builddir)/src/.libs/
+
+mtdev_kernel_SOURCES = mtdev-kernel.c
+mtdev_kernel_LDFLAGS = -L$(top_builddir)/src/.libs/ -lmtdev
diff --git a/test/mtdev-kernel.c b/test/mtdev-kernel.c
new file mode 100644
index 0000000..1f33c3e
--- /dev/null
+++ b/test/mtdev-kernel.c
@@ -0,0 +1,158 @@
+/*****************************************************************************
+ *
+ * mtdev - Multitouch Protocol Translation Library (MIT license)
+ *
+ * Copyright (C) 2010 Henrik Rydberg <rydberg@euromail.se>
+ * Copyright (C) 2010 Canonical Ltd.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ ****************************************************************************/
+
+#include <../src/common.h>
+#include <stdio.h>
+#include <time.h>
+
+/*
+ * Combinatorial formulation
+ *
+ * x_ij = 1 if slot i and contact j are connected, zero otherwise
+ *
+ * sum_i x_ij <= 1 for all j; each contact picks at most one slot
+ *
+ * sum_j x_ij <= 1 for all i; each slot is picked by at most one contact
+ *
+ * sum_ij x_ij == min(nslot, npos); assign every contact possible
+ *
+ * Arrange x_ij as a bitmask; x_00 x_01 x_02.. x_10 x_11 x_12...
+ *
+ * Up to five slots, this is readily enumerable.
+ */
+
+#define SLOT_MAX	5
+#define SLOT_CNT	(SLOT_MAX + 1)
+
+static int illegal(int nslot, int npos, unsigned x)
+{
+	int i, j, sum;
+
+	for (j = 0; j < npos; j++) {
+		sum = 0;
+		for (i = 0; i < nslot; i++)
+			sum += GETBIT(x, i * npos + j);
+		if (sum > 1)
+			return 1;
+	}
+	for (i = 0; i < nslot; i++) {
+		sum = 0;
+		for (j = 0; j < npos; j++)
+			sum += GETBIT(x, i * npos + j);
+		if (sum > 1)
+			return 1;
+	}
+
+	sum = bitcount(x);
+	return sum != minval(nslot, npos);
+}
+
+static void get_slots(int *slots, int nslot, int npos, unsigned x)
+{
+	int i;
+
+	memset(slots, -1, sizeof(slots[0]) * npos);
+	for (i = 0; i < nslot * npos; i++)
+		if (GETBIT(x, i))
+			slots[i % npos] = i / npos;
+	for (i = 0; i < npos; i++)
+		if (slots[i] < 0)
+			slots[i] = nslot++;
+}
+
+static int generate_assignments(int nslot, int npos)
+{
+	static int ncol;
+	unsigned x, nx = BITMASK(nslot * npos);
+	int slots[SLOT_MAX];
+	int i, n = 0;
+
+	for (x = 0; x < nx; x++) {
+		if (illegal(nslot, npos, x))
+			continue;
+		for (i = 0; i < nslot * npos; i++) {
+			if (GETBIT(x, i)) {
+				if (ncol++ % 16 == 0)
+					printf("\n\t%d,", i);
+				else
+					printf(" %d,", i);
+				n++;
+			}
+		}
+		get_slots(slots, nslot, npos, x);
+		for (i = 0; i < npos; i++) {
+			if (ncol++ % 16 == 0)
+				printf("\n\t%d,", slots[i]);
+			else
+				printf(" %d,", slots[i]);
+			n++;
+		}
+	}
+
+	return n;
+}
+
+int main(int argc, char *argv[])
+{
+	int ix[SLOT_CNT][SLOT_CNT], nix = 0;
+	int eslot, i, j;
+
+	if (argc < 2) {
+		fprintf(stderr, "usage: %s <num_slots>\n", argv[0]);
+		return 1;
+	}
+
+	eslot = atoi(argv[1]) + 1;
+	if (eslot > SLOT_CNT) {
+		fprintf(stderr, "allowed slot range: 2 - %d\n", SLOT_MAX);
+		return 1;
+	}
+
+	printf("\n/* generated by mtdev-kernel - do not edit */\n");
+	printf("static const u8 match_data[] = {");
+	for (i = 0; i < eslot; i++) {
+		for (j = 0; j < eslot; j++) {
+			ix[i][j] = nix;
+			nix += generate_assignments(i, j);
+		}
+	}
+	printf("\n};\n");
+
+	printf("\n/* generated by mtdev-kernel - do not edit */\n");
+	printf("static const int match_index[][%d] = {\n", eslot);
+	for (i = 0; i < eslot; i++) {
+		printf("\t{");
+		for (j = 0; j < eslot; j++)
+			printf(" %d%s", ix[i][j], j < eslot - 1 ? "," : "");
+		printf(" },\n");
+	}
+	printf("\t{ %d }\n", nix);
+	printf("};\n");
+
+	return 0;
+}