apps/examples/module: Add a test harness for testing NuttX kernel modules

ChangeLog.txt

@@ -1498,4 +1498,6 @@
 	  at /dev/telnetN (2015-12-07).
 	* netutils/ping: Unfinished implementation of ping/ping6 using raw
 	  sockets (2015-12-11).
+	* examples/module:  Add a test harness for verifying NuttX kernel
+	  modules (2015-12-12).
 

examples/Kconfig

@@ -33,6 +33,7 @@ source "$APPSDIR/examples/ltdc/Kconfig"
 source "$APPSDIR/examples/media/Kconfig"
 source "$APPSDIR/examples/mm/Kconfig"
 source "$APPSDIR/examples/modbus/Kconfig"
+source "$APPSDIR/examples/module/Kconfig"
 source "$APPSDIR/examples/mount/Kconfig"
 source "$APPSDIR/examples/mtdpart/Kconfig"
 source "$APPSDIR/examples/mtdrwb/Kconfig"

examples/README.txt

@@ -738,6 +738,68 @@ examples/mm
 
   This is a simple test of the memory manager.
 
+examples/module
+^^^^^^^^^^^^^^
+
+  This example builds a small loadable module test case.  This includes on
+  character driver under examples/module/drivers.  This driver is  built using
+  the relocatable ELF format and installed in a ROMFS file system.  At run time,
+  the driver module is loaded and exercises.  Requires CONFIG_MODULE.
+  Other configuration options:
+
+    CONFIG_EXAMPLES_ELF_DEVMINOR - The minor device number of the ROMFS block
+      driver. For example, the N in /dev/ramN. Used for registering the RAM
+      block driver that will hold the ROMFS file system containing the ELF
+      executables to be tested.  Default: 0
+
+    CONFIG_EXAMPLES_ELF_DEVPATH - The path to the ROMFS block driver device.  This
+      must match EXAMPLES_ELF_DEVMINOR. Used for registering the RAM block driver
+      that will hold the ROMFS file system containing the ELF executables to be
+      tested.  Default: "/dev/ram0"
+
+  NOTES:
+
+  1. CFLAGS should be provided in CELFFLAGS.  RAM and FLASH memory regions
+     may require long allcs.  For ARM, this might be:
+
+       CELFFLAGS = $(CFLAGS) -mlong-calls
+
+     Similarly for C++ flags which must be provided in CXXELFFLAGS.
+
+  2. Your top-level nuttx/Make.defs file must also include an approproate definition,
+     LDELFFLAGS, to generate a relocatable ELF object.  With GNU LD, this should
+     include '-r' and '-e <entry point>'.
+
+       LDELFFLAGS = -r -e module_initialize
+
+     If you use GCC to link, you make also need to include '-nostdlib' or
+     '-nostartfiles' and '-nodefaultlibs'.
+
+  3. This example also requires genromfs.  genromfs can be build as part of the
+     nuttx toolchain.  Or can built from the genromfs sources that can be found
+     in the NuttX tools repository (genromfs-0.5.2.tar.gz).  In any event, the
+     PATH variable must include the path to the genromfs executable.
+
+  4. ELF size:  The ELF files in this example are, be default, quite large
+     because they include a lot of "build garbage".  You can greatly reduce the
+     size of the ELF binaries are using the 'objcopy --strip-unneeded' command to
+     remove un-necessary information from the ELF files.
+
+  5. Simulator.  You cannot use this example with the the NuttX simulator on
+     Cygwin.  That is because the Cygwin GCC does not generate ELF file but
+     rather some Windows-native binary format.
+
+     If you really want to do this, you can create a NuttX x86 buildroot toolchain
+     and use that be build the ELF executables for the ROMFS file system.
+
+  6. Linker scripts.  You might also want to use a linker scripts to combine
+     sections better.  An example linker script is at nuttx/sched/module/gnu-elf.ld.
+     That example might have to be tuned for your particular linker output to
+     position additional sections correctly.  The GNU LD LDELFFLAGS then might
+     be:
+
+       LDELFFLAGS = -r -e module_initialize -T$(TOPDIR)/sched/module/gnu-elf.ld
+
 examples/modbus
 ^^^^^^^^^^^^^^^
 

examples/module/.gitignore

@@ -0,0 +1,3 @@
+/Make.dep
+/.depend
+/.built

examples/module/Kconfig

@@ -0,0 +1,45 @@
+#
+# For a description of the syntax of this configuration file,
+# see the file kconfig-language.txt in the NuttX tools repository.
+#
+
+config EXAMPLES_MODULE
+	bool "Module Example"
+	default n
+	---help---
+		Enable the module example
+
+if EXAMPLES_MODULE
+
+config EXAMPLES_MODULE_LIBC
+	bool "Link with LIBC"
+	default n
+	depends on !BUILD_KERNEL
+	---help---
+		Link with the C library (and also math library if it was built).
+		By default, all undefined symbols must be provided via a symbol
+		table.  But if this option is selected, then each MODULE test program
+		will link with the SYSCALL library and will interface with the OS
+		system calls.  You probably will NOT want this option, however,
+		because it will substantially increase the size of code.  For
+		example, a separate copy of printf() would be linked with every
+		program greatly increasing the total code size.  This option is
+		primarily intended only for testing.
+
+config EXAMPLES_MODULE_DEVMINOR
+	int "ROMFS Minor Device Number"
+	default 0
+	---help---
+		The minor device number of the ROMFS block. For example, the N in /dev/ramN.
+		Used for registering the RAM block driver that will hold the ROMFS file system
+		containing the MODULE executables to be tested.  Default: 0
+
+config EXAMPLES_MODULE_DEVPATH
+	string "ROMFS Device Path"
+	default "/dev/ram0"
+	---help---
+		The path to the ROMFS block driver device.  This must match EXAMPLES_MODULE_DEVMINOR.
+		Used for registering the RAM block driver that will hold the ROMFS file system
+		containing the MODULE executables to be tested.  Default: "/dev/ram0"
+
+endif

examples/module/Make.defs

@@ -0,0 +1,38 @@
+############################################################################
+# apps/examples/module/Make.defs
+#
+#   Copyright (C) 2015 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.
+#
+############################################################################
+
+ifeq ($(CONFIG_EXAMPLES_MODULE),y)
+CONFIGURED_APPS += examples/module
+endif

examples/module/Makefile

@@ -0,0 +1,151 @@
+############################################################################
+# apps/examples/module/Makefile
+#
+#   Copyright (C) 2015 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
+
+# Module example built-in application info
+
+APPNAME = module
+PRIORITY = SCHED_PRIORITY_DEFAULT
+STACKSIZE = 2048
+
+# Module Example
+
+ASRCS =
+CSRCS = symtab.c
+MAINSRC = module_main.c
+
+AOBJS = $(ASRCS:.S=$(OBJEXT))
+COBJS = $(CSRCS:.c=$(OBJEXT))
+MAINOBJ = $(MAINSRC:.c=$(OBJEXT))
+
+SRCS = $(ASRCS) $(CSRCS) $(MAINSRC)
+OBJS = $(AOBJS) $(COBJS)
+
+ifneq ($(CONFIG_BUILD_KERNEL),y)
+  OBJS += $(MAINOBJ)
+endif
+
+ifeq ($(CONFIG_WINDOWS_NATIVE),y)
+  BIN = ..\..\libapps$(LIBEXT)
+else
+ifeq ($(WINTOOL),y)
+  BIN = ..\\..\\libapps$(LIBEXT)
+else
+  BIN = ../../libapps$(LIBEXT)
+endif
+endif
+
+ifeq ($(WINTOOL),y)
+  INSTALL_DIR = "${shell cygpath -w $(BIN_DIR)}"
+else
+  INSTALL_DIR = $(BIN_DIR)
+endif
+
+CONFIG_XYZ_PROGNAME ?= discover$(EXEEXT)
+PROGNAME = $(CONFIG_XYZ_PROGNAME)
+
+ROOTDEPPATH = --dep-path . --dep-path drivers
+
+# Build targets
+
+VPATH = drivers
+
+all: .built
+.PHONY: really_build clean_drivers clean depend distclean
+
+$(AOBJS): %$(OBJEXT): %.S
+	$(call ASSEMBLE, $<, $@)
+
+$(COBJS) $(MAINOBJ): %$(OBJEXT): %.c
+	$(call COMPILE, $<, $@)
+
+# This is a little messy.  The build is broken into two pieces:  (1) the
+# drivers/ subdir build that auto-generates several files, and (2) the real
+# build.  This is done because we need a fresh build context after auto-
+# generating the source files.
+
+really_build: $(OBJS)
+	$(call ARCHIVE, $(BIN), $(OBJS))
+	@touch .built
+
+.built:
+	@$(MAKE) -C drivers TOPDIR="$(TOPDIR)" APPDIR="$(APPDIR)" CROSSDEV=$(CROSSDEV)
+	@$(MAKE) TOPDIR="$(TOPDIR)" APPDIR="$(APPDIR)" really_build
+
+ifeq ($(CONFIG_BUILD_KERNEL),y)
+$(BIN_DIR)$(DELIM)$(PROGNAME): $(OBJS) $(MAINOBJ)
+	@echo "LD: $(PROGNAME)"
+	$(Q) $(LD) $(LDELFFLAGS) $(LDLIBPATH) -o $(INSTALL_DIR)$(DELIM)$(PROGNAME) $(ARCHCRT0OBJ) $(MAINOBJ) $(LDLIBS)
+	$(Q) $(NM) -u  $(INSTALL_DIR)$(DELIM)$(PROGNAME)
+
+install: $(BIN_DIR)$(DELIM)$(PROGNAME)
+
+else
+install:
+
+endif
+
+ifeq ($(CONFIG_NSH_BUILTIN_APPS),y)
+$(BUILTIN_REGISTRY)$(DELIM)$(APPNAME)_main.bdat: $(DEPCONFIG) Makefile
+	$(call REGISTER,$(APPNAME),$(PRIORITY),$(STACKSIZE),$(APPNAME)_main)
+
+context: $(BUILTIN_REGISTRY)$(DELIM)$(APPNAME)_main.bdat
+else
+context:
+endif
+
+# We can't make dependencies in this directory because the required
+# header files may not yet exist.
+
+.depend:
+	@touch $@
+
+depend: .depend
+
+clean_drivers:
+	@$(MAKE) -C drivers TOPDIR="$(TOPDIR)" APPDIR="$(APPDIR)" CROSSDEV=$(CROSSDEV) clean
+
+clean: clean_drivers
+	$(call DELFILE, .built)
+	$(call CLEAN)
+
+distclean: clean
+	$(call DELFILE, Make.dep)
+	$(call DELFILE, .depend)
+
+-include Make.dep

examples/module/drivers/.gitignore

@@ -0,0 +1,6 @@
+/romfs
+/romfs.h
+/romfs.img
+/symtab.c
+/varlist.tmp
+

examples/module/drivers/Makefile

@@ -0,0 +1,98 @@
+############################################################################
+# apps/examples/module/drivers/Makefile
+#
+#   Copyright (C) 2015 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
+
+ALL_SUBDIRS = chardev 
+BUILD_SUBDIRS = chardev 
+
+MODULE_DIR = $(APPDIR)/examples/module
+DRIVER_DIR = $(MODULE_DIR)/drivers
+ROMFS_DIR = $(DRIVER_DIR)/romfs
+ROMFS_IMG = $(DRIVER_DIR)/romfs.img
+ROMFS_HDR = $(DRIVER_DIR)/romfs.h
+SYMTAB_SRC = $(DRIVER_DIR)/symtab.c
+
+define DIR_template
+$(1)_$(2):
+	$(Q) $(MAKE) -C $(1) $(3) TOPDIR="$(TOPDIR)" APPDIR="$(APPDIR)" ROMFS_DIR="$(ROMFS_DIR)" CROSSDEV=$(CROSSDEV)
+endef
+
+all: $(ROMFS_HDR) $(DIRLIST_HDR) $(SYMTAB_SRC)
+.PHONY: all build clean install populate
+
+$(foreach DIR, $(BUILD_SUBDIRS), $(eval $(call DIR_template,$(DIR),build, all)))
+$(foreach DIR, $(ALL_SUBDIRS), $(eval $(call DIR_template,$(DIR),clean,clean)))
+$(foreach DIR, $(BUILD_SUBDIRS), $(eval $(call DIR_template,$(DIR),install,install)))
+
+# Build program(s) in each sud-directory
+
+build: $(foreach DIR, $(BUILD_SUBDIRS), $(DIR)_build)
+
+# Install each program in the romfs directory
+
+install: $(foreach DIR, $(BUILD_SUBDIRS), $(DIR)_install)
+
+# Create the romfs directory
+
+$(ROMFS_DIR):
+	$(Q) mkdir $(ROMFS_DIR)
+
+# Populate the romfs directory
+
+populate:  $(ROMFS_DIR) build install
+
+# Create the romfs.img file from the populated romfs directory
+
+$(ROMFS_IMG): populate
+	$(Q) genromfs -f $@ -d $(ROMFS_DIR) -V "MODULETEST"
+
+# Create the romfs.h header file from the romfs.img file
+
+$(ROMFS_HDR) : $(ROMFS_IMG)
+	$(Q) (cd $(DRIVER_DIR); xxd -i romfs.img | sed -e "s/^unsigned/static const unsigned/g" >$@)
+
+# Create the exported symbol table
+
+$(SYMTAB_SRC): build
+	$(Q) $(DRIVER_DIR)/mksymtab.sh $(ROMFS_DIR) >$@
+
+# Clean each subdirectory
+
+clean: $(foreach DIR, $(ALL_SUBDIRS), $(DIR)_clean)
+	$(Q) rm -f $(ROMFS_HDR) $(DIRLIST_HDR) $(ROMFS_IMG) $(SYMTAB_SRC)
+	$(Q) rm -rf $(ROMFS_DIR)

examples/module/drivers/chardev/.gitignore

@@ -0,0 +1,2 @@
+hello
+

examples/module/drivers/chardev/Makefile

@@ -0,0 +1,81 @@
+############################################################################
+# examples/module/drivers/chardev/Makefile
+#
+#   Copyright (C) 2015 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 $(TOPDIR)/Make.defs
+
+ifeq ($(WINTOOL),y)
+NUTTXLIB = "${shell cygpath -w $(TOPDIR)$(DELIM)lib}"
+else
+NUTTXLIB = "$(TOPDIR)$(DELIM)lib"
+endif
+
+KDEFINE = ${shell $(TOPDIR)/tools/define.sh "$(CC)" __KERNEL__}
+CFLAGS += $(KDEFINE)
+
+ifeq ($(CONFIG_EXAMPLES_MODULE_LIBC),y)
+LDMODULEFLAGS += -Bstatic
+LDLIBPATH +=  -L $(NUTTXLIB)
+endif
+
+ifeq ($(CONFIG_EXAMPLES_MODULE_LIBC),y)
+ifeq ($(CONFIG_BUILD_PROTECTED),y)
+LDLIBS += -luc
+else
+LDLIBS += -lc
+endif
+endif
+
+BIN = chardev
+
+SRCS = $(BIN).c
+OBJS = $(SRCS:.c=$(OBJEXT))
+
+all: $(BIN)
+
+$(OBJS): %$(OBJEXT): %.c
+	@echo "CC: $<"
+	$(Q) $(CC) -c $(CMODULEFLAGS) $< -o $@
+
+$(BIN): $(OBJS)
+	@echo "LD: $<"
+	$(Q) $(LD) $(LDMODULEFLAGS) $(LDLIBPATH) -o $@ $(ARCHCRT0OBJ) $^ $(LDLIBS)
+
+clean:
+	$(call DMODULEILE, $(BIN))
+	$(call CLEAN)
+
+install:
+	$(Q) mkdir -p $(ROMFS_DIR)
+	$(Q) install $(BIN) $(ROMFS_DIR)/$(BIN)

examples/module/drivers/chardev/chardev.c

@@ -0,0 +1,142 @@
+/****************************************************************************
+ * apps/examples/module/drivers/chardev/chardev.c
+ *
+ *   Copyright (C) 2015 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 <nuttx/config.h>
+
+#include <sys/types.h>
+#include <stdbool.h>
+#include <string.h>
+#include <errno.h>
+#include <syslog.h>
+#include <debug.h>
+
+#include <nuttx/fs/fs.h>
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+#ifndef MIN
+#  define MIN(a,b) ((a) < (b) ? (a) : (b))
+#endif
+
+/****************************************************************************
+ * Private data
+ ****************************************************************************/
+
+static const char g_read_string[] = "Hi there, apps/examples/module test\n";
+
+/****************************************************************************
+ * Private Function Prototypes
+ ****************************************************************************/
+
+static ssize_t chardev_read(FAR struct file *filep, FAR char *buffer,
+                 size_t buflen);
+static ssize_t chardev_write(FAR struct file *filep, FAR const char *buffer,
+                 size_t buflen);
+
+/****************************************************************************
+ * Private Data
+ ****************************************************************************/
+
+static const struct file_operations chardev_fops =
+{
+  0,             /* open */
+  0,             /* close */
+  chardev_read,  /* read */
+  chardev_write, /* write */
+  0,             /* seek */
+  0              /* ioctl */
+#ifndef CONFIG_DISABLE_POLL
+  , 0            /* poll */
+#endif
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+  , 0            /* unlink */
+#endif
+};
+
+/****************************************************************************
+ * Private Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: chardev_read
+ ****************************************************************************/
+
+static ssize_t chardev_read(FAR struct file *filep, FAR char *buffer,
+                            size_t len)
+{
+  size_t rdlen = strlen(g_read_string);
+  ssize_t ret = MIN(len, rdlen);
+
+  memcpy(buffer, g_read_string, ret);
+
+  syslog(LOG_INFO, "chardev_read: Returning %d bytes\n", (int)ret);
+  lib_dumpbuffer("chardev_read: Returning", (FAR const uint8_t *)buffer, ret);
+  return ret;
+}
+
+/****************************************************************************
+ * Name: chardev_write
+ ****************************************************************************/
+
+static ssize_t chardev_write(FAR struct file *filep, FAR const char *buffer,
+                             size_t len)
+{
+  syslog(LOG_INFO, "chardev_write: Writing %d bytes\n", (int)len);
+  lib_dumpbuffer("chardev_write: Writing", (FAR const uint8_t *)buffer, len);
+  return len;
+}
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: module_initialize
+ *
+ * Description:
+ *   Register /dev/zero
+ *
+ ****************************************************************************/
+
+void module_initialize(void)
+{
+  (void)register_driver("/dev/chardev", &chardev_fops, 0666, NULL);
+}

examples/module/drivers/mksymtab.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+
+usage="Usage: $0 <test-dir-path>"
+
+# Check for the required ROMFS directory path
+
+dir=$1
+if [ -z "$dir" ]; then
+	echo "ERROR: Missing <test-dir-path>"
+	echo ""
+	echo $usage
+	exit 1
+fi
+
+if [ ! -d "$dir" ]; then
+	echo "ERROR: Directory $dir does not exist"
+	echo ""
+	echo $usage
+	exit 1
+fi
+
+# Extract all of the undefined symbols from the MODULE files and create a
+# list of sorted, unique undefined variable names.
+
+varlist=`find ${dir} -executable -type f | xargs nm | fgrep ' U ' | sed -e "s/^[ ]*//g" | cut -d' ' -f2 | sort | uniq`
+
+# Now output the symbol table as a structure in a C source file.  All
+# undefined symbols are declared as void* types.  If the toolchain does
+# any kind of checking for function vs. data objects, then this could
+# faile
+
+echo "#include <nuttx/compiler.h>"
+echo "#include <nuttx/binfmt/symtab.h>"
+echo ""
+
+for var in $varlist; do
+	echo "extern void *${var};"
+done
+
+echo ""
+echo "const struct symtab_s exports[] = "
+echo "{"
+
+for var in $varlist; do
+	echo "  {\"${var}\", &${var}},"
+done
+
+echo "};"
+echo ""
+echo "const int nexports = sizeof(exports) / sizeof(struct symtab_s);"
+

examples/module/module_main.c

@@ -0,0 +1,209 @@
+/****************************************************************************
+ * examples/module/module_main.c
+ *
+ *   Copyright (C) 2015 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 <nuttx/config.h>
+#include <nuttx/compiler.h>
+
+#include <sys/mount.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <fcntl.h>
+#include <string.h>
+#include <syslog.h>
+#include <errno.h>
+#include <debug.h>
+
+#include <nuttx/fs/ramdisk.h>
+#include <nuttx/module.h>
+#include <nuttx/binfmt/symtab.h>
+
+#include "drivers/romfs.h"
+
+/****************************************************************************
+ * Pre-processor Definitions
+ ****************************************************************************/
+
+/* Check configuration.  This is not all of the configuration settings that
+ * are required -- only the more obvious.
+ */
+
+#if CONFIG_NFILE_DESCRIPTORS < 1
+#  error "You must provide file descriptors via CONFIG_NFILE_DESCRIPTORS in your configuration file"
+#endif
+
+#ifndef CONFIG_MODULE
+#  error "You must select CONFIG_MODULE in your configuration file"
+#endif
+
+#ifndef CONFIG_FS_ROMFS
+#  error "You must select CONFIG_FS_ROMFS in your configuration file"
+#endif
+
+#ifdef CONFIG_DISABLE_MOUNTPOINT
+#  error "You must not disable mountpoints via CONFIG_DISABLE_MOUNTPOINT in your configuration file"
+#endif
+
+/* Describe the ROMFS file system */
+
+#define SECTORSIZE   64
+#define NSECTORS(b)  (((b)+SECTORSIZE-1)/SECTORSIZE)
+#define MOUNTPT      "/mnt/romfs"
+
+#ifndef CONFIG_EXAMPLES_MODULE_DEVMINOR
+#  define CONFIG_EXAMPLES_MODULE_DEVMINOR 0
+#endif
+
+#ifndef CONFIG_EXAMPLES_MODULE_DEVPATH
+#  define CONFIG_EXAMPLES_MODULE_DEVPATH "/dev/ram0"
+#endif
+
+/****************************************************************************
+ * Private data
+ ****************************************************************************/
+
+static const char g_write_string[] = "Hi there, installed driver\n";
+
+/****************************************************************************
+ * Symbols from Auto-Generated Code
+ ****************************************************************************/
+
+extern const struct symtab_s exports[];
+extern const int nexports;
+
+/****************************************************************************
+ * Public Functions
+ ****************************************************************************/
+
+/****************************************************************************
+ * Name: module_main
+ ****************************************************************************/
+
+#ifdef CONFIG_BUILD_KERNEL
+int main(int argc, FAR char *argv[])
+#else
+int module_main(int argc, char *argv[])
+#endif
+{
+  struct module_s module;
+  char buffer[128];
+  ssize_t nbytes;
+  int ret;
+  int fd;
+
+  /* Create a ROM disk for the ROMFS filesystem */
+
+  printf("Registering romdisk at /dev/ram%d\n", CONFIG_EXAMPLES_MODULE_DEVMINOR);
+  ret = romdisk_register(CONFIG_EXAMPLES_MODULE_DEVMINOR, (FAR uint8_t *)romfs_img,
+                         NSECTORS(romfs_img_len), SECTORSIZE);
+  if (ret < 0)
+    {
+      fprintf(stderr, "ERROR: romdisk_register failed: %d\n", ret);
+      exit(EXIT_FAILURE);
+    }
+
+  /* Mount the file system */
+
+  printf("Mounting ROMFS filesystem at target=%s with source=%s\n",
+         MOUNTPT, CONFIG_EXAMPLES_MODULE_DEVPATH);
+
+  ret = mount(CONFIG_EXAMPLES_MODULE_DEVPATH, MOUNTPT, "romfs", MS_RDONLY, NULL);
+  if (ret < 0)
+    {
+      fprintf(stderr, "ERROR: mount(%s,%s,romfs) failed: %s\n",
+              CONFIG_EXAMPLES_MODULE_DEVPATH, MOUNTPT, errno);
+      exit(EXIT_FAILURE);
+    }
+
+  /* Install the character driver  */
+
+  memset(&module, 0, sizeof(struct module_s));
+  module.filename = MOUNTPT "/chardev";
+  module.exports  = exports;
+  module.nexports = nexports;
+
+  ret = insmod(&module);
+  if (ret < 0)
+    {
+      fprintf(stderr, "ERROR: insmod failed: %d\n", ret);
+      exit(EXIT_FAILURE);
+    }
+
+  /* Open the installed character driver */
+
+  fd = open("/dev/chardev", O_RDWR);
+  if (fd < 0)
+    {
+      int errcode = errno;
+      fprintf(stderr, "ERROR: Failed to open /dev/chardev: %d\n", errcode);
+      exit(EXIT_FAILURE);
+    }
+
+  /* Read from the character driver */
+
+  nbytes = read(fd, buffer, 128);
+  if (nbytes < 0)
+    {
+      int errcode = errno;
+      fprintf(stderr, "ERROR: Read from /dev/chardev failed: %d\n", errcode);
+      close(fd);
+      exit(EXIT_FAILURE);
+    }
+
+  printf("Read %d bytes: %d\n", (int)nbytes);
+  lib_dumpbuffer("Bytes read", (FAR const uint8_t *)buffer, nbytes);
+
+  /* Write to the character driver */
+
+  nbytes = write(fd, g_write_string, strlen(g_write_string));
+  if (nbytes < 0)
+    {
+      int errcode = errno;
+      fprintf(stderr, "ERROR: Write to /dev/chardev failed: %d\n", errcode);
+      close(fd);
+      exit(EXIT_FAILURE);
+    }
+
+  printf("Wrote %d bytes: %d\n", (int)nbytes);
+  lib_dumpbuffer("Bytes read", (FAR const uint8_t *)g_write_string, nbytes);
+
+  close(fd);
+  return EXIT_SUCCESS;
+}