diff --git a/Makefile b/Makefile
index 17b14ce04..0a118e6b8 100644
--- a/Makefile
+++ b/Makefile
@@ -52,7 +52,7 @@ SUBDIRS = examples graphics interpreters modbus builtin nshlib netutils
SUBDIRS += platform system
# The list of configured directories is derived from NuttX configuration
-# file: The selected applications are enabled settings in the confuration
+# file: The selected applications are enabled settings in the configuration
# file. For example,
#
# CONFIG_EXAMPLES_HELLO=y
diff --git a/system/Kconfig b/system/Kconfig
index ed16af860..d2434afab 100644
--- a/system/Kconfig
+++ b/system/Kconfig
@@ -63,6 +63,10 @@ menu "SD Card"
source "$APPSDIR/system/sdcard/Kconfig"
endmenu
+menu "Sudoku"
+source "$APPSDIR/system/sudoku/Kconfig"
+endmenu
+
menu "Sysinfo"
source "$APPSDIR/system/sysinfo/Kconfig"
endmenu
diff --git a/system/Make.defs b/system/Make.defs
index bdfde4503..125a2ffec 100644
--- a/system/Make.defs
+++ b/system/Make.defs
@@ -98,6 +98,10 @@ ifeq ($(CONFIG_SYSTEM_SDCARD),y)
CONFIGURED_APPS += system/sdcard
endif
+ifeq ($(CONFIG_SYSTEM_SUDOKU),y)
+CONFIGURED_APPS += system/sudoku
+endif
+
ifeq ($(CONFIG_SYSTEM_SYSINFO),y)
CONFIGURED_APPS += system/sysinfo
endif
diff --git a/system/Makefile b/system/Makefile
index ed7b64dff..f5d35bfc6 100644
--- a/system/Makefile
+++ b/system/Makefile
@@ -38,9 +38,8 @@
# Sub-directories containing system task
SUBDIRS = cdcacm cle composite flash_eraseall free i2c hex2bin inifile
-SUBDIRS += install nxplayer poweroff ramtest ramtron readline sdcard
-SUBDIRS += stackmonitor sysinfo usbmonitor usbmsc vi zmodem
-SUBDIRS += mdio
+SUBDIRS += install mdio nxplayer poweroff ramtest ramtron readline sdcard
+SUBDIRS += stackmonitor sudoku sysinfo usbmonitor usbmsc vi zmodem
# Create the list of installed runtime modules (INSTALLED_DIRS)
diff --git a/system/sudoku/Kconfig b/system/sudoku/Kconfig
new file mode 100644
index 000000000..cdb28f4f3
--- /dev/null
+++ b/system/sudoku/Kconfig
@@ -0,0 +1,27 @@
+#
+# For a description of the syntax of this configuration file,
+# see misc/tools/kconfig-language.txt.
+#
+
+config SYSTEM_SUDOKU
+ bool "Sudoku"
+ default n
+ select SYSTEM_READLINE
+ ---help---
+ Enable the sudoku game.
+
+if SYSTEM_SUDOKU
+
+config SYSTEM_SUDOKU_STACKSIZE
+ int "Sudoku stack size"
+ default 1536
+ ---help---
+ The size of stack allocated for the Sudoku task.
+
+config SYSTEM_SUDOKU_PRIORITY
+ int "Sudoku priority"
+ default 100
+ ---help---
+ The priority of the Sudoku task.
+
+endif
diff --git a/system/sudoku/Makefile b/system/sudoku/Makefile
new file mode 100644
index 000000000..c0500f371
--- /dev/null
+++ b/system/sudoku/Makefile
@@ -0,0 +1,117 @@
+############################################################################
+# apps/system/sudoku/Makefile
+#
+# Copyright (C) 2014 Gregory Nutt. All rights reserved.
+# Author: Gregory Nutt <gnutt@nuttx.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+#
+# 1. Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+# notice, this list of conditions and the following disclaimer in
+# the documentation and/or other materials provided with the
+# distribution.
+# 3. Neither the name NuttX nor the names of its contributors may be
+# used to endorse or promote products derived from this software
+# without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+# FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+# COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+# INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+# BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+# OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+# AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+# ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+# POSSIBILITY OF SUCH DAMAGE.
+#
+############################################################################
+
+-include $(TOPDIR)/.config
+-include $(TOPDIR)/Make.defs
+include $(APPDIR)/Make.defs
+
+ifeq ($(WINTOOL),y)
+INCDIROPT = -w
+endif
+
+# Sudoku Application
+
+CONFIG_SYSTEM_SUDOKU_STACKSIZE ?= 1536
+CONFIG_SYSTEM_SUDOKU_PRIORITY ?= 100
+
+STACKSIZE = $(CONFIG_SYSTEM_SUDOKU_STACKSIZE)
+PRIORITY = $(CONFIG_SYSTEM_SUDOKU_PRIORITY)
+
+ASRCS =
+CSRCS = sudoku.c
+
+AOBJS = $(ASRCS:.S=$(OBJEXT))
+COBJS = $(CSRCS:.c=$(OBJEXT))
+
+SRCS = $(ASRCS) $(CSRCS)
+OBJS = $(AOBJS) $(COBJS)
+
+ifeq ($(CONFIG_WINDOWS_NATIVE),y)
+ BIN = ..\..\libapps$(LIBEXT)
+else
+ifeq ($(WINTOOL),y)
+ BIN = ..\\..\\libapps$(LIBEXT)
+else
+ BIN = ../../libapps$(LIBEXT)
+endif
+endif
+
+ROOTDEPPATH = --dep-path .
+
+# Common build
+
+VPATH =
+
+all: .built
+.PHONY: context depend clean distclean
+
+$(AOBJS): %$(OBJEXT): %.S
+ $(call ASSEMBLE, $<, $@)
+
+$(COBJS): %$(OBJEXT): %.c
+ $(call COMPILE, $<, $@)
+
+.built: $(OBJS)
+ $(call ARCHIVE, $(BIN), $(OBJS))
+ $(Q) touch .built
+
+# Register application
+
+ifeq ($(CONFIG_NSH_BUILTIN_APPS),y)
+$(BUILTIN_REGISTRY)$(DELIM)sudoku.bdat: $(DEPCONFIG) Makefile
+ $(call REGISTER,"sudoku",$(PRIORITY),$(STACKSIZE),sudoku_main)
+
+context: $(BUILTIN_REGISTRY)$(DELIM)sudoku.bdat
+else
+context:
+endif
+
+# Create dependencies
+
+.depend: Makefile $(SRCS)
+ $(Q) $(MKDEP) $(ROOTDEPPATH) "$(CC)" -- $(CFLAGS) -- $(SRCS) >Make.dep
+ $(Q) touch $@
+
+depend: .depend
+
+clean:
+ $(call DELFILE, .built)
+ $(call CLEAN)
+
+distclean: clean
+ $(call DELFILE, Make.dep)
+ $(call DELFILE, .depend)
+
+-include Make.dep
diff --git a/system/sudoku/sudoku.c b/system/sudoku/sudoku.c
new file mode 100755
index 000000000..80fbfbc82
--- /dev/null
+++ b/system/sudoku/sudoku.c
@@ -0,0 +1,573 @@
+/****************************************************************************
+ * apps/system/sudoku/sudoku.c
+ *
+ * Copyright (C) 2014 Gregory Nutt. All rights reserved.
+ * Author: Gregory Nutt <gnutt@nuttx.org>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in
+ * the documentation and/or other materials provided with the
+ * distribution.
+ * 3. Neither the name NuttX nor the names of its contributors may be
+ * used to endorse or promote products derived from this software
+ * without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ****************************************************************************/
+
+/****************************************************************************
+ * Included Files
+ ****************************************************************************/
+
+#include <stdint.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <apps/readline.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#define NHISTORY 16
+
+/****************************************************************************
+ * Private Types
+ ****************************************************************************/
+
+struct sudoku_s
+{
+ uint16_t canbe;
+ uint16_t is;
+};
+typedef struct sudoku_s sudoku_t[81];
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static sudoku_t history[NHISTORY];
+static sudoku_t working;
+static int first;
+static int last;
+static int current;
+
+static const char *r1[8] =
+ {" ", "1 ", " 2 ", "12 ", " 3", "1 3", " 23", "123" };
+static const char *r2[8] =
+ {" ", "4 ", " 5 ", "45 ", " 6", "4 6", " 56", "456" };
+static const char *r3[8] =
+ {" ", "7 ", " 8 ", "78 ", " 9", "7 9", " 89", "789" };
+static char line[256];
+static int nis = 0;
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+static inline void init_array(void)
+{
+ int i;
+
+ first = 0;
+ last = 0;
+ current = 0;
+
+ for (i = 0; i < 81; i++)
+ {
+ working[i].canbe = 0x1ff;
+ working[i].is = 0x000;
+ }
+}
+
+static inline void push(void)
+{
+ int next = current + 1;
+ if (next >= NHISTORY) next = 0;
+
+ if (current == last)
+ {
+ last = next;
+ }
+
+ if (first == next)
+ {
+ if (++first >= NHISTORY) first = 0;
+ }
+
+ memcpy (history[current], working, sizeof(sudoku_t));
+ current = next;
+}
+
+static inline void undo(void)
+{
+ if (current == first)
+ {
+ printf("Cannot undo\n");
+ }
+ else
+ {
+ if (--current < 0) current = NHISTORY-1;
+ memcpy (working, history[current], sizeof(sudoku_t));
+ }
+}
+
+static inline void redo(void)
+{
+ if (current == last)
+ {
+ printf("Cannot redo\n");
+ }
+ else
+ {
+ if (++current >= NHISTORY) current = 0;
+ memcpy(working, history[current], sizeof(sudoku_t));
+ }
+}
+
+static inline void show_row(int row)
+{
+ printf(" |%3s|%3s|%3s| |%3s|%3s|%3s| |%3s|%3s|%3s|\n",
+ r1[working[9*row + 0].canbe & 0x007],
+ r1[working[9*row + 1].canbe & 0x007],
+ r1[working[9*row + 2].canbe & 0x007],
+ r1[working[9*row + 3].canbe & 0x007],
+ r1[working[9*row + 4].canbe & 0x007],
+ r1[working[9*row + 5].canbe & 0x007],
+ r1[working[9*row + 6].canbe & 0x007],
+ r1[working[9*row + 7].canbe & 0x007],
+ r1[working[9*row + 8].canbe & 0x007]);
+ printf(" %2d |%3s|%3s|%3s| |%3s|%3s|%3s| |%3s|%3s|%3s|\n", row + 1,
+ r2[(working[9*row + 0].canbe >> 3) & 0x007],
+ r2[(working[9*row + 1].canbe >> 3) & 0x007],
+ r2[(working[9*row + 2].canbe >> 3) & 0x007],
+ r2[(working[9*row + 3].canbe >> 3) & 0x007],
+ r2[(working[9*row + 4].canbe >> 3) & 0x007],
+ r2[(working[9*row + 5].canbe >> 3) & 0x007],
+ r2[(working[9*row + 6].canbe >> 3) & 0x007],
+ r2[(working[9*row + 7].canbe >> 3) & 0x007],
+ r2[(working[9*row + 8].canbe >> 3) & 0x007]);
+ printf(" |%3s|%3s|%3s| |%3s|%3s|%3s| |%3s|%3s|%3s|\n",
+ r3[(working[9*row + 0].canbe >> 6) & 0x007],
+ r3[(working[9*row + 1].canbe >> 6) & 0x007],
+ r3[(working[9*row + 2].canbe >> 6) & 0x007],
+ r3[(working[9*row + 3].canbe >> 6) & 0x007],
+ r3[(working[9*row + 4].canbe >> 6) & 0x007],
+ r3[(working[9*row + 5].canbe >> 6) & 0x007],
+ r3[(working[9*row + 6].canbe >> 6) & 0x007],
+ r3[(working[9*row + 7].canbe >> 6) & 0x007],
+ r3[(working[9*row + 8].canbe >> 6) & 0x007]);
+}
+
+static inline void show_array(void)
+{
+ int row;
+ int i;
+
+ printf(" +===+===+===+ +===+===+===+ +===+===+===+\n");
+ printf(" | 1 | 2 | 3 | | 4 | 5 | 6 | | 7 | 8 | 9 |\n");
+ printf(" +===+===+===+ +===+===+===+ +===+===+===+\n");
+
+ row = 0;
+ for (i = 0; i < 3; i++)
+ {
+ show_row(row++);
+ printf(" +---+---+---+ +---+---+---+ +---+---+---+\n");
+ show_row(row++);
+ printf(" +---+---+---+ +---+---+---+ +---+---+---+\n");
+ show_row(row++);
+ printf(" +===+===+===+ +===+===+===+ +===+===+===+\n");
+ }
+}
+
+static inline int is_unique(unsigned int val)
+{
+ switch (val)
+ {
+ case 0x001:
+ case 0x002:
+ case 0x004:
+ case 0x008:
+ case 0x010:
+ case 0x020:
+ case 0x040:
+ case 0x080:
+ case 0x100:
+ return 1;
+ default:
+ return 0;
+ }
+}
+
+static inline int impossible(void)
+{
+ int nchanges = 0;
+ unsigned int val;
+ int row1, col1;
+ int row2, col2;
+ int i, j;
+ int ndx1, ndx2;
+
+ for (row1 = 0; row1 < 9; row1++)
+ {
+ row2 = row1 / 3;
+ for (col1 = 0; col1 < 9; col1++)
+ {
+ col2 = col1 / 3;
+ ndx1 = row1*9 + col1;
+ val = working[ndx1].canbe;
+
+ for (i = 0; i < 9; i++)
+ {
+ ndx2 = i*9 + col1;
+ if (ndx1 != ndx2)
+ {
+ val &= ~working[ndx2].is;
+ }
+ }
+
+ for (j = 0; j < 9; j++)
+ {
+ ndx2 = row1*9 + j;
+ if (ndx1 != ndx2)
+ {
+ val &= ~working[ndx2].is;
+ }
+ }
+
+ for (i = 0; i < 3; i++)
+ {
+ for (j = 0; j < 3; j++)
+ {
+ ndx2 = (row2*3 + i)*9 + (col2*3 + j);
+ if (ndx1 != ndx2)
+ {
+ val &= ~working[ndx2].is;
+ }
+ }
+ }
+
+ if (val == 0)
+ {
+ return -1;
+ }
+
+ if (val != working[ndx1].canbe)
+ {
+ nchanges++;
+ working[ndx1].canbe = val;
+
+ if (is_unique(val))
+ {
+ working[ndx1].is = val;
+ }
+ }
+ }
+ }
+
+ return nchanges;
+}
+
+static inline int unique(void)
+{
+ int noccurences[9];
+ int lastndx[9];
+ int nchanges = 0;
+ unsigned int mask;
+ unsigned int val;
+ int row1, col1;
+ int row2, col2;
+ int ndx;
+ int i;
+
+ for (row1 = 0; row1 < 9; row1++)
+ {
+ for (i = 0; i < 9; i++)
+ {
+ noccurences[i] = 0;
+ lastndx[i] = -1;
+ }
+
+ for (i = 0; i < 9; i++)
+ {
+ mask = 1 << i;
+ for (col1 = 0; col1 < 9; col1++)
+ {
+ ndx = row1 * 9 + col1;
+ if (working[ndx].canbe & mask)
+ {
+ noccurences[i]++;
+ lastndx[i] = ndx;
+ }
+ }
+
+ for (i = 0; i < 9; i++)
+ {
+ if (noccurences[i] == 1)
+ {
+ val = 1 << i;
+ ndx = lastndx[i];
+ if (working[ndx].is != val)
+ {
+ working[ndx].is = val;
+ working[ndx].canbe = val;
+ nchanges++;
+ }
+ }
+ }
+ }
+ }
+
+ for (col1 = 0; col1 < 9; col1++)
+ {
+ for (i = 0; i < 9; i++)
+ {
+ noccurences[i] = 0;
+ lastndx[i] = -1;
+ }
+
+ for (i = 0; i < 9; i++)
+ {
+ mask = 1 << i;
+ for (row1 = 0; row1 < 9; row1++)
+ {
+ ndx = row1 * 9 + col1;
+ if (working[ndx].canbe & mask)
+ {
+ noccurences[i]++;
+ lastndx[i] = ndx;
+ }
+ }
+
+ for (i = 0; i < 9; i++)
+ {
+ if (noccurences[i] == 1)
+ {
+ val = 1 << i;
+ ndx = lastndx[i];
+ if (working[ndx].is != val)
+ {
+ working[ndx].is = val;
+ working[ndx].canbe = val;
+ nchanges++;
+ }
+ }
+ }
+ }
+ }
+
+ for (row2 = 0; row2 < 3; row2++)
+ {
+ for (col2 = 0; col2 < 3; col2++)
+ {
+ for (i = 0; i < 9; i++)
+ {
+ noccurences[i] = 0;
+ lastndx[i] = -1;
+ }
+
+ for (i = 0; i < 9; i++)
+ {
+ mask = 1 << i;
+ for ( row1 = 0; row1 < 3; row1++)
+ {
+ for ( col1 = 0; col1 < 3; col1++)
+ {
+ ndx = (row2*3 + row1)*9 + (col2*3 + col1);
+ if (working[ndx].canbe & mask)
+ {
+ noccurences[i]++;
+ lastndx[i] = ndx;
+ }
+ }
+ }
+ }
+
+ for (i = 0; i < 9; i++)
+ {
+ if (noccurences[i] == 1)
+ {
+ val = 1 << i;
+ ndx = lastndx[i];
+ if (working[ndx].is != val)
+ {
+ working[ndx].is = val;
+ working[ndx].canbe = val;
+ nchanges++;
+ }
+ }
+ }
+ }
+ }
+
+ return nchanges;
+}
+
+static inline int getcell(int *pndx, int *pval)
+{
+ int row, col, ndx;
+ unsigned int val;
+ int i = 0;
+
+ while ((line[i] == ' ' || line[i] == '\t') && (line[i] != '\0') && (line[i] != '\n')) i++;
+
+ if (line[i] < '1' || line[i] > '9')
+ {
+ printf("Bad row: %c\n", line[i]);
+ return -1;
+ }
+ row = line[i++] -'0' - 1;
+
+ while ((line[i] == ' ' || line[i] == '\t') && (line[i] != '\0') && (line[i] != '\n')) i++;
+
+ if (line[i] < '1' || line[i] > '9')
+ {
+ printf("Bad col: %c\n", line[i]);
+ return -1;
+ }
+ col = line[i++] -'0' - 1;
+ ndx = row*9 + col;
+
+ while ((line[i] == ' ' || line[i] == '\t') && (line[i] != '\0') && (line[i] != '\n')) i++;
+
+ if (line[i] < '1' || line[i] > '9')
+ {
+ printf("Bad value: %c\n", line[i]);
+ return -1;
+ }
+
+ val = 1 << ((line[i] - '0') - 1);
+ if (( val & working[ndx].canbe) == 0)
+ {
+ printf("Impossible value: %c\n", line[i]);
+ return -1;
+ }
+
+ *pndx = ndx;
+ *pval = val;
+ return 0;
+}
+
+static inline int get_command(void)
+{
+ printf("%d of 81> ", nis);
+ fflush(stdout);
+ (void)readline(line, 256, stdin, stdout);
+
+ int i = 0;
+
+ while ((line[i] == ' ' || line[i] == '\t') && (line[i] != '\0') && (line[i] != '\n')) i++;
+
+ return line[i];
+}
+
+static inline void show_usage(void)
+{
+ printf("ABC - Set cell[A,B] to C where A,B, and C are in {1..9}\n");
+ printf("U - Undo last cell assignment\n");
+ printf("R - Redo last cell assignment\n");
+ printf("H|? - Show this message\n");
+ printf("Q - Quit\n");
+}
+
+static inline void count_cells(void)
+{
+ int i;
+
+ nis = 0;
+ for (i = 0; i < 81; i++) if (working[i].is > 0) nis++;
+}
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+int sudoku_main(int argc, char **argv, char **envp)
+{
+ int cmd;
+ int nchanged;
+ int val;
+ int ndx;
+
+ init_array();
+ for (;;)
+ {
+ count_cells();
+ show_array();
+ if (nis == 81)
+ {
+ printf("GAME OVER: 81 of 81 assigned\n");
+ return 0;
+ }
+ else
+ {
+ cmd = get_command();
+ switch (cmd)
+ {
+ case 'U':
+ case 'u':
+ undo();
+ break;
+
+ case 'R':
+ case 'r':
+ redo();
+ break;
+
+ case 'H':
+ case 'h':
+ case '?':
+ show_usage();
+ break;
+
+ case 'Q':
+ case 'q':
+ return 0;
+
+ default:
+ if (getcell(&ndx, &val) == 0)
+ {
+ push();
+ working[ndx].is = val;
+ working[ndx].canbe = val;
+ for (;;)
+ {
+ nchanged = impossible();
+ if (nchanged < 0)
+ {
+ printf("This move is not possible\n");
+ undo();
+ break;
+ }
+ else if (nchanged == 0)
+ {
+ nchanged = unique();
+ if (nchanged == 0)
+ {
+ break;
+ }
+ }
+ }
+ }
+ }
+ }
+ }
+}