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      - apps/platform:  Create gnu/ subdirectory that contains the one and
        only GNU C++ initialization function.  Remove all other C++
        initialization functions.

Bugfixes.  Only the most critical bugfixes are listed here (see the
ChangeLog for the complete list of bugfixes and for additional, more
detailed bugfix information):

    * Core OS:

      - Priority inheritance:  When CONFIG_SEM_PREALLOCHOLDERS==0, there is
        only a single, hard-allocated holder structure.  This is problem
        because in sem_wait() the holder is released, but needs to remain in
        the holder container until sem_restorebaseprio() is called.  The call
        to sem_restorebaseprio() must be one of the last things the
        sem_wait() does because it can cause the task to be suspended. If in
        sem_wait(), a new task gets the semaphore count then it will fail to
        allocate the holder and will not participate in priority
        inheritance.  This fix is to add two hard-allocated holders in the
        sem_t structure:  One of the old holder and one for the new holder.
      - Priority inheritance:  sem_holder sem_findholder missing
        inintalization of pholder.  sem_findholder would fail and code
        optimization covered this up.  From David Sidrane.
      - Partial Fix priority inheritance CONFIG_SEM_PREALLOCHOLDERS=0.  From
        David Sidrane.
      - Priority inheritance:  sem_boostholderprio prevent overrun of
        pend_reprios.  The second case rtcb->sched_priority <=
        htcb->sched_priority did not check if there is sufficient space in
        the pend_reprios array.  From David Sidrane.
      - lp_worker:  Guard from pend_reprios overlow.  From David Sidrane.
      - Priority inheritance: Fixes improper restoration of base_priority in
        the case of CONFIG_SEM_PREALLOCHOLDERS=0.  The call to
        sem_restorebaseprio_task context switches in the
        sem_foreachholder(sem, sem_restoreholderprioB, stcb); call prior to
        releasing the holder. So the running task is left as a holder as is
        the started task. Leaving both slots filled thus failing to perform
        the boost/or restoration on the correct tcb.  This PR fixes this by
        releasing the running task slot prior to reprioritization that can
        lead to the context switch.  To faclitate this, the interface to
        sem_restorebaseprio needed to take the tcb from the holder prior to
        the holder being freed. In the failure case where sched_verifytcb
        fails it added the overhead of looking up the holder.  There is also
        the additional thunking on the foreach to get from holer to
        holder->tcb.  An alternate approach could be to leve the interface
        the same and allocate a holder on the stack of sem_restoreholderprioB
        copy the sem's holder to it, free it as is done in this pr and and
        then pass that address sem_restoreholderprio as the holder. It could
        then get the holder's tcb but we would keep the same sem_findholder
        in sched_verifytcb.  From David Sidrane.
      - Priority inheritance:  Fixes improper restoration of base_priority.
        From David Sidrane.
      - sem_holder:  Indexing error.  From David Sidrane.

          if (sem->holder[0].htcb != NULL || sem->holder[**1**].htcb != NULL)
      - realloc():  When realloc() has to fall back to calling malloc(), size
        including overhead was being provided to malloc(), causing a slightly
        larger allocation than needed.  Noted by initialkjc@yahoo.com.
      - scheduler:  Fix tg_flags check with GROUP_FLAG_NOCLDWAIT.  From Masayuki
        Ishikawa.
      - scheduler:  Fix CHILD_FLAG_EXITED in include/nuttx/sched.h.  From
        Masayuki Ishikawa.
      - binfmt/elf:  Fix offset value when calling elf_read() in
        elf_symname().  From Masayuki Ishikawa.
      - binfmt/elf:  Fix offset value when calling elf_read() in
        elf_sectname().  From Masayuki Ishikawa.
      - There can be a failure in IOB allocation to some asynchronous
        behavior caused by the use of sem_post().  Consider this scenario:
        (1) Task A holds an IOB.  There are no further IOBs.  The value of
        semcount is zero. Task B calls iob_alloc().  Since there are not
        IOBs, it calls sem_wait().  The value of semcount is now -1.  (2)
        Task A frees the IOB.  iob_free() adds the IOB to the free list and
        calls sem_post() this makes Task B ready to run and sets semcount to
        zero NOT 1.  There is one IOB in the free list and semcount is zero.
        When Task B wakes up it would increment the sem_count back to the
        correct value.  (3) But an interrupt or another task runs occurs
        before Task B executes.  The interrupt or other tak takes the IOB off
        of the free list and decrements the semcount.  But since semcount is
        then < 0, this causes the assertion because that is an invalid state
        in the interrupt handler. So I think that the root cause is that
        there the asynchrony between incrementing the semcount.  This change
        separates the list of IOBs:  Currently there is only a free list of
        IOBs.  The problem, I believe, is because of asynchronies due
        sem_post() post cause the semcount and the list content to become out
        of sync.  This change adds a new 'committed' list:  When there is a
        task waiting for an IOB, it will go into the committed list rather
        than the free list before the semaphore is posted.  On the waiting
        side, when awakened from the semaphore wait, it will expect to find
        its IOB in the committed list, rather than free list.  In this way,
        the content of the free list and the value of the semaphore count
        always remain in sync.
      - binfmt:  Fix .dtor memory allocation.  From Masayuki Ishikawa.

    * File System/Block and MTD Drivers:

      - SmartFS:  If whence is SEEK_END, the file offset shall be set to the
        size of the file plus offset. Noted by eunb.song@samsung.com.
      - mtd/progmem:  Fix incorrect target address calculation.
        progmem_read/write() is incorrectly calculating the target address,
        expecting the offset argument is given in a block number. This is
        completely wrong and as a result invalid flash region is accessed.
        Byte-oriented read/write interfaces of mtd device accept the target
        address in a byte offset, not a block number.  From Heesub Shin.
      - procfs:  Fix wrong member IDs are displayed when 'cat
        /proc/<pid>/group/status'.  From Nobutaka Toyoshima.
      - procfs:  Fix incorrect uptime with CONFIG_SYSTEM_TIME64.  From
        Masayuki Ishikawa.
      - vfs/poll: round timeout up to next full tick.  Calling poll() with
        timeout less than half tick (thus MSEC2TICK(timeout) => 0) caused
        returning error with EAGAIN. Instead of rounding timeout down, value
        should be rounded up. Open Group spec for poll says:
        "Implementations may place limitations on the granularity of timeout
        intervals. If the requested timeout interval requires a finer
        granularity than the implementation supports, the actual timeout
        interval will be rounded up to the next supported value."  From Jussi
        Kivilinna.
      - mtd/config:  erase block between block read and write.  From Juha
        Niskanen.
      - mtd:  Build RAMTRON and AT45DB drivers only if selected.  From Juha
        Niskanen.
      - mtd/config:  Fix byte read interface test.  From Juha Niskanen.
      - mtd:  Fix some unallocated and NULL pointer issues.  rwb->wrflush and
        rwb->wrmaxblocks in rwbuffer could get unallocated values from
        ftl_initialize() in some configurations.  Also fixes related assert:

          up_assert: Assertion failed at file:rwbuffer.c line: 643

        that can happen with the following configuration:

          CONFIG_FTL_WRITEBUFFER=y
          CONFIG_DRVR_WRITEBUFFER=y
          # CONFIG_FS_WRITABLE is not set

        These problems are caused by CONFIG variable differences between the
        buffer layers. TODO: This is not a perfect solution. readahead
        support has similar issues.  From Juha Niskanen.
      - net procfs:  Fix buffer corruption and refactor netdev_statistics.c.
        From Masayuki Ishikawa.
      - FAT:  Fix 'Missing unlock' in fs_fat32.c.  From Masayuki Ishikawa.
      - VFS fdopen:  Add missing file stream flags clearing.  Clear file
        stream structure regardless of config options. Structure clearing is
        needed as previous use of stream list entry might leave fs_flags
        set.  From Harri Luhtala.
      - mtd/smart: Fix use of uninitialized variable.  From Jussi Kivilinna.
      - mtd/w25.c:  Enable short delay after sector/chip erase.  From Jussi
        Kivilinna.
      - mtd/config:  Add some error checks for I/O errors.  From Juha
        Niskanen.

    * Graphics/Graphic Drivers:

      - net procfs:  Some long lines were being generated that cause buffer-
        related problems and corrupted output.

    * Networking/Network Drivers:

      - Fixed wrong assert on udp dgram send.  From Pascal Speck.
      - TCP/IPv6: Fix a compile issue when IPv6, but not IPv4 is enabled.
      - net/socket/accept:  Fix building with CONFIG_NET_LOCAL_STREAM.  From
        Jussi Kivilinna.
      - Argument of network device IOCTL should be unsigned long, just as
        will all other IOCTL methods.
      - net/socket:  Fix cloning of local and raw sockets.  From Jussi
        Kivilinna.
      - TCP:  Wait for 3-Way Handshare before accept() returns.  From Simon
        Piriou.
      - TCP:  Send RST if applicaiton 'unlistens()' before we complete the
        connection sequence.
      - TCP:  An RST received during the 3-way handshake requires a little
        more clean-up.
      - IPv6:  Fix net_ipv6_pref2mask().  From Masayuki Ishikawa.
      - network IOCTL commands:  The only place in net/netdev/netdev_ioctl.c
        where the interface state should change is for SIOCSIFFLAGS.  The
        other ones .. SIOCSIFADDR, SIOSLIFADDR, SIODIFADDR ..  should not
        change the link state.  From Sebastien Lorquet.
      - TCP:  Fix tcp_findlistner() in dual stack mode.  From Masayuki
        Ishikawa.

    * Common Drivers:

      - Fix as5048b by adding missing frequency parameter.  From Andreas
        Bihlmaier.
      - multiple fixes in nrf24l01 driver:  (1) signal POLLIN if there is
        already data in the FIFO, (2) send ETIMEDOUT to userspace after 2
        seconds if TX IRQ was not received, (3) handle FIFO overflow, (4)
        handle invalid pipes/empty FIFO, and (5) multiple cosmetics (missing
        static, duplicate define, missing \n).  From Leif Jakob.
      - input/mxt:  Prevent overriding i2c transfer return value.
        put_reg/get_reg function was overriding i2c transfer error code with
        i2creset return value, that lead to OK status although actual
        transfer failed.  From Juha Niskanen.
      - drivers/audio/wm8904:  WM8904 has same problem as that fixed by Juha
        Niskanen in the MaxTouch driver.
      - UART 16550:  Missing left parenthesis in function prototype.  This is
        Bitbucket Issue #41.
      - USBMSC:  Fix a wrong lun number issue.  From Masayuki Ishikawa.
      - drivers/i2c:  Fix compile issues if CONFIG_DISABLE_PSEUDOFS_OPERATIONS
        is enabled.
      - drivers/serial: I discovered a problem in the file
        drivers/serial/serial.c concerning the function uart_close(…). In the
        case that a serial device is opened with the flag O_NONBLOCK the
        function uart_close(…) blocks until all data in the buffer is
        transmitted. The function close(…) called on an handle opened with
        O_NONBLOCK should not block. The problem occurred with a CDC/ACM
        device.  From Stefan Kolb.
      - drivers:  Fix some bad NULL checks.  From Juha Niskanen.
      - drivers:  Rename newly introduced up_i2creset to I2C_RESET.  From
        Juha Niskanen.
      - drivers/bch:  BCH character driver bch_ioctl() always returns -ENOTTY
        for DIOC_GETPRIV command.  It should returns OK if DIOC_GETPRIV
        command succeeds.  From  EunBong Song.
      - Replace sprintf() with snprintf() in pipe.c.  From Nobutaka Toyoshima.
      - drivers/bch:  Fix 'Missing Unlock' in bchdev_driver.c.  From Masayuki
        Ishikawa.
      - button_upper:  Fix interrupt enabling for poll-events.  From Jussi
        Kivilinna.
      - drivers/{sensors,usbmisc}:  Fix uninitialized I2C frequency.  From
        Juha Niskanen.

    * ARM:

      - Set EABI stack alignment for all ARM architectures (remove OABI
        code).  From David Cabecinhas.
      - Remove redundant interrupt stack coloring and OABI code.  From David
        Cabecinhas.
      - Fix off-by-one interrupt stack allocation in 8-byte aligned
        architectures.  From David Cabecinhas.

    * ARMv6-M:

      - CONFIG_DEBUG_HARDFAULT should be available for Cortex-M0 too.

    * Microchip/Atmel SAM3/4 Drivers:

      - SAM3/4:  Fixed configurations for TWI master.  Obviously an
        incomplete port from SAMA5.

    * Microchip/Atmel SAMv7 Drivers:

      - SAMV7: Watchdog:  Fix Forbidden Window Value.  According the Datasheet
        the WDD Value is the lower bound of a so called Forbidden Window and
        to disable this we have to set the WDD Value greater than or equal to
        the WDV Value.  This seems to be a bug in the datasheet. It looks
        like we have to set it to a greater value than the WDV to really
        disable this Thing.  When triggering the Watchdog faster than the
        (very slow) clock source of the Watchdog fires, this Forbidden Window
        Feature resets the System if WDD equals to WDV.  This Changeset
        disables the Forbidden Window by setting the WDD Value to the Maximum
        (0xfff) Value possible.  From Frank Benkert.
      - SAMV7 EMAC:  Add conditional logic to account the fact that the
        SAMV71 has 6 rather than 3 queues after version 1.  From Ian McAfee.

    * NXP/Freescale Kinetis Drivers:

      - Kinetis:  Fixed GPIO _PIN_OUTPUT_LOWDRIVE swapped with
        _PIN_OUTPUT_OPENDRAIN.  From David Sidrane.
      - Ensure interrupts are back on BEFORE running code dependant on
        clock_systimer.  From David Sidrane.
      - Kinetis k66, k64, k60, k40, k20: Pin mux configure all I2C signals as
        Open Drain.  The output structure of the GPIO for I2C needs to be
        open drain.  When left at the default, one can observe on a scope the
        slave contending with the push-pull during the ACK.  From David
        Sidrane.
      - Kinetis K66:  Fixed TMP2_CH1 definition.  From David Sidrane.
      - Kinetis K66:  Define ALT1 to match ref manual.  From David Sidrane.
      - Kinetis K66:  GPIO and pin mux cleanup.  From David Sidrane.
      - Kinetis ADC:  Various corrections and updates.  From David Sidrane.

    * NXP/Freescale LPC43xx:

      - Add missing PINCONF_INBUFFER in several places of
        lpc4310203050_pinconfig.h.  From Andreas Bihlmaier.
      - Fix logic in preprocessor checks and correct arguments to
        lpc43_pin_config initialization.  From Andreas Bihlmaier.

    * NXP/Freescale LPC43xx Drivers:

      - Fix logic error in lpc43_adc.  From Andreas Bihlmaier.
      - Use correct macro for irqid (fortunately both point to
        LPC43_IRQ_EXTINT+18).  From Andreas Bihlmaier.
      - Actually write modified value to register.  From Andreas Bihlmaier.
      - Increase number of supported PWM channels from 4 to 6.  From Andreas
        Bihlmaier.

    * Silicon Labs EFM32 Drivers:

      - EFM32 I2C: Fix timeout calculation.  From Masayuki Ishikawa.

    * STMicro STM32:

      - As discovered by dcabecinhas.  This fix assume the 8 byte alignment
        options for size stack size or this will overwrite the first word
        after TOS.  See
        https://github.com/PX4/Firmware/issues/6613#issuecomment-285869778.
        From David Sidrane.
      - STM32 F7:  In stm32_allocateheap.c There are 5 not 4 configurations.
        From David Sidrane.

    * STMicro STM32 Drivers:

      - STM32, STM32 F7, STM32 L4:  OTG host drivers: Do not do data toggle
        if interrupt transfer is NAKed.  Sugested by webbbn@gmail.com.
      - Save elapsed time before handling I2C in stm32_i2c_sem_waitstop().
        This change follows the same logic as in previous fix to
        stm32_i2c_sem_waitdone().  It is possible that a context switch
        occurs after I2C registers are read but before elapsed time is saved
        in stm32_i2c_sem_waitstop(). It is then possible that the registers
        were read only once with "elapsed time" equal 0. When scheduler
        resumes this thread it is quite possible that now "elapsed time" will
        be well above timeout threshold. In that case the function returns
        and reports a timeout, even though the registers were not read
        "recently". Fix this by inverting the order of operations in the loop
        - save elapsed time before reading registers. This way a context
        switch anywhere in the loop will not cause an erroneous "timeout"
        error.  From Freddie Chopin.
      - STM32, STM32 F7, and STM32 L4:  Clone Freddie Chopin's I2C change to
        similar STM32 I2C drivers.  From David Sidrane.
      - STM32:  OTG host implementations of stm32_in_transfer() must obey the
        polling interval for the case of isochronous and interrupt endpoints.
      - STM32:  Fix erase sector number for microcontrolers with more than 11
        sectors.  Erase a sector from the second bank cause the bit 4 of SNB
        being set but never unsed, so trying to erase a sector from the first
        bank was acually eraseing a sector from the second bank.  From José
        Roberto de Souza.
      - STM32:  Make up_progmem thread safe.  Writing to a flash sector while
        starting the erase of other sector have a undefined behavior so lets
        add a semaphore and syncronize access to Flash registers.  But for
        the semaphore to work it needs to be initialized so each board needs
        call stm32_flash_initialize() on initialization, so to avoid runtime
        problems it is only using semaphore and making it thread safe if
        initialized, after all boards starts to call stm32_flash_initialize()
        we can remove the boolean and the check.  From José Roberto de Souza.
      - STM32:  Add workaround for flash data cache corruption on
        read-while-write.  This is a known hardware issue on some STM32 see
        the errata of your model and if you make use of both memory banks you
        should enable it.  From José Roberto de Souza.
      - STM32 Flash fixes.  From José Roberto de Souza.
      - STM32 Flash:  Missing unlock on F1 HSI off path.  From David Sidrane.
      - STM32 F4 I2C: I needed to use DS3231, I remember that in past it
        worked ok, but now for stm32f4xx is used another driver (chip
        specific, stm32f40xxx_i2c.c) and DS3231 driver doesn't work.  After
        investigating a problem I found that I2C driver (isr routine) has a
        few places there it sends stop bit even if not all messages are
        managed. So, e.g., removing stm32_i2c_sendstop (#1744) and adding
        stm32_i2c_sendstart after data reading helps to make DS3231 working.
        From  Alexander Oryshchenko; verified by David Sidrane.
      - STM32 F7 Serial:  Serial fix for dropped data:  (1) Revert the
        inherited dma bug from the stm32.  see
        https://bitbucket.org/nuttx/nuttx/commits/df9ae3c13fc2fff2c21ebdb098c520b11f43280d
        for details.  And (2) Most all CR1-CR3 settings can not be configured
        while UE is true. Threfore we make all operation atomic and disable
        UE and restore it's originalstate on exit.  From David Sidrane.
      - STM32 L1:  Fix IWDG and WWDG debug mode stop for STM32L15XX.  From
        Juha Niskanen.
      - STM32 F7:  Fix UART7 and UART8 IFLOWCONTROL options.  From Jussi
        Kivilinna.
      - STM32 F7:  Add warning for RXDMA + IFLOWCONTROL combination.
        Combination of RXDMA + IFLOWCONTROL does not work as one might
        expect.  Since RXDMA uses circular DMA-buffer, DMA will always keep
        reading new data from USART peripheral even if DMA buffer underruns.
        Thus this combination only does following: RTS is asserted on USART
        setup and deasserted on shutdown and does not perform actual RTS
        flow-control.  Data loss can be demonstrated by doing long up_mdelay
        inside irq critical section and feeding data to RXDMA+IFLOWCONTROL
        UART.  From Jussi Kivilinna.
      - STM32 F7 Serial:  Do not stop processing input in SW flow-control
        mode.  From Jussi Kivilinna.
      - STM32 L4 DMA: Correct bad channel definition.  From Sebastien Lorquet.
      - STM32 F7:  Warn if no DMA2 configured when using ADC with DMA.  Also
        correct ADC channel numbers that DMA callback passes to upper half
        driver.  From Juha Niskanen.
      - STM32 F7 ADC:  Do not override ADCPRE_DIV when measuring
        internal voltage.  From Juha Niskanen.
      - STM32 L4:  Don't think these chips have DPFPU, DTCM or ITCM.  From
        Juha Niskanen.
      - STM32 F7 Flash:  macro naming errors, there is no FLASH_CONFIG_F for
        F7.  From Juha Niskanen.
      - STM32 L4: stm32l4x6xx_pinmap:  Update I2C4 and DCMI pins.  From Juha
        Niskanen.
      - STM32 L4: stm32l4_i2c: change wrong macro to CONFIG_I2C_POLLED.  From
        Juha Niskanen.
      - Fix STM32F7 I2C interrupt handler.  From Jussi Kivilinna.
      - STM32:  Serial Allow configuring Rx DMA buffer size.  From David
        Sidrane.
      - STM32 CAN: I had the problem that the transmit FIFO size (= actual
        elements in FIFO) was slowly increasing over time, and was full after
        a few hours.  The reason was that the code hit the line
        "canerr("ERROR: No available mailbox\n");" in stm32_cansend, so
        can_xmit thinks it has sent the packet to the hardware, but actually
        has not. Therefore the transmit interrupt never happens which would
        call can_txdone, and so the size of the FIFO size does not decrease.
        The reason why the code actually hit the mentioned line above, is
        because stm32can_txready uses a different (incomplete) condition than
        stm32can_send to determine if the mailbox can be used for sending,
        and thus can_xmit forwards the packet to stm32can_send.
        stm32can_txready considered mailboxes OK for sending if the mailbox
        was empty, but did not consider that mailboxes may not yet be used if
        the request completed bit is set - stm32can_txinterrupt has to
        process these mailboxes first.  Note that I have also modified
        stm32can_txinterrupt - I removed the if condition, because the CAN
        controller retries to send the packet until it succeeds. Also if the
        condition would not evaluate to true, can_txdone would not be called
        and the FIFO size would not decrease also.  From Lederhilger Martin.
      - STM32 Serial:  Fix freezing serial port.  Serial interrupt
        enable/disable functions do not disable interrupts and can freeze
        device when serial interrupt is received while execution is at those
        functions. Trivially triggered with two or more threads write to
        regular syslog stream and to emergency stream. In this case, freeze
        happens because of mismatch of priv->ie (TXEIE == 0) and actually
        enabled interrupts in USART registers (TXEIE == 1), which leads to
        unhandled TXE interrupt and causes interrupt storm for USART.  From
        Jussi Kivilinna.
      - STM32 I2C:  Make private symbols static.  From Juha Niskanen.
      - STM32 L4 GPIO:  Put back EXTI line source selection.  From Juha
        Niskanen.
      - STM32 L4 RTC:  Store RTC MAGIC to backup reg, not to address zero.
        From Juha Niskanen.

    * STMicro STM32 Boards:

      - Disable serial console on stm32f103-minimum usbnsh example project
        config. Devices enumerate after this change.  From Bob Ryan.
      - Nucleo-144:  Default for choice in Kconfig was not one of the
        possible choices.
      - Nucleo-F4X1RE User LEDS: Issue #51 reports compilation problems with
        stm32_userled.c.  Reported by Gappi92.

    * TI Tiva Drivers:

      - Tiva I2C:  Correct an error in conditional compilation.
      - Tiva SSI:  Resolves issue 52 'Copy-Paste error in
        tiva_ssibus_initialize()' submitted by Aleksandr Kazantsev.

    * C Library/Header Files:

      - C Library vsnprintf():  Fix precision for string formatting.  Fixes
        use of format precision to truncate input string.  From Jussi
        Kivilinna.
      - C Library vsnprintf():  If size is zero, then vsnprintf() should
        return the size of the required buffer without writing anything.
        From Jussi Kivilinna.
      - C Library netdb: in dns_query_callback, ret != -EADDRNOTAVAIL
        condition consumes error returns including EAGAIN in this case,
        dns query retransmission doesn't work.  From Ritajina.
      - C Library netdb:  Fix time info in lib_dnscache.c.  From Masayuki
        Ishikawa.
      - C Library netdb: Fix bugs in lib_gethostbynamer.c. This fix sets
        h_name in struct hostent returned by gethostbyname().  From Masayuki
        Ishikawa.
      - C Library Defect Workaround: replace '%6.6u' format with an
        equivalent '%06u'.  From Tomasz Wozniak.

    * Tools

      - Fix mksyscall host binary name.  From Alan Carvalho de Assis.

    * Applications (apps/)

      - Fix some calls to task_create():  argv[0] is the first parameter, not
        the name of the task.
      - Bitbucket Issue 5:  I found an unexpected behavior in apps/
        configuration generation. Adding external symbolic link in apps/
        directory and using Make.defs for Kconfig generation, Kconfig file
        has a wrong path in the source argument. It contains original dir
        path outside of the source tree instead path to sub-directory in
        apps/.  The problem is connected with make/system symbolic link path
        resolution.  Corrected by a patch submitted by Artur Madrzak with
        Issue 5.
      - apps/: Make more globals static to avoid name clashes.  From Juha
        Niskanen.

    * NSH: apps/nshlib:

      - NSH library:  In nsh_argexand(), if CONFIG_NSH_ARGCAT is defined but
        CONFIG_NSH_CMDPARMS defined and/or CONFIG_DISABLE_ENVIRON not
        defined, then there is a situation that causes an infinite loop in
        the parser.  Noted by Freddie Chopin.
      - NSH library:  Fix building when CONFIG_NET_USRSOCK enabled with other
        link-layers.  From Jussi Kivilinna.
      - NSH library:  Fix some warnings about integer/pointer casts of
        different sizes (probably only effects 64-bit simulation).
      - NSH library:  Fix open flags in nsh_codeccmd.c.  From Masayuki
        Ishikawa.
      - I need to look at the registers that are at or around 0xe000ef90.
        Using mw and xd, I see that nsh does not support pointers greater
        than 0x7fffffff.  A quick look at the source shows that the pointers
        for those two commands are set with calls to strtol() rather than
        strtoul().  Changing the two pointer-setting instances to strtoul()
        fixes the problem, at least for my architecture/config.  From Ian
        McAfee.
      - NSH library: Fix a resource leak in cmd_hexdump().  From Nobutaka
        Toyoshima.

    * Examples/Tests: apps/examples:

      - apps/examples/hidkbd:  Remove call to arch_usbhost_initialize().
        That is violation of the OS interfacing rules and will no longer be
        supported.  USB host should be initialized as part of the normal
        board bring-up logic as with any other devices and should not involve
        illegal calls from applications into the OS.
      - apps/examples/usbterm:  Removed because it is not very useful and
        because it can be configured to use an illegal call into the OS.
      - examples/mm: Fix Makefile.  Built-in was not being registered.
      - examples/hidkbd:  Add some missing configuration settings.
      - examples/random:  Avoid stack overflows.  From Juha Niskanen.
      - examples/nettest:  Fix an error in pre-processor expression.
      - examples/mtdpart:  Prevent part array overflow.  mtdpart examples
        create partions and allocate from 1 index not a 0 index to part[]
        array. This cause buffer overflow for part array.  This change fixes
        this problem.  From  EunBong Song.
      - examples/can:  Fix can example app to print data when
        CONFIG_EXAMPLES_CAN_READ is defined.  From Alan Carvalho de Assis.
    * Network Utilies: apps/netutils:

      - Not a clean fix, but at least makes DHCP working with
        CONFIG_NETDEV_MULTINIC.  From Andreas Bihlmaier.
      - Ensure netlib will not be broken when setip will not bring the
        network up anymore.  From Sebastien Lorquet.

    * CAN Utilies: apps/canutils:

      - Fix libcanard github download link to get it compiling correctly.
        From Alan Carvalho de Assis.
      - Fix to use the new canardInit() function.  From Alan Carvalho de
        Assis.

    * System Unitilities (apps/system)

      - system/dhcpc:  Add missing argument of fprintf.

    * Tools (apps/tools):

      - The dedicated windows tool at tools/mkkconfig.bat uses $APPSDIR,
        which is not a windows shell variable, and is left uninitialized, but
        in fact should be the current directory.  From Sebastien Lorquet.

NuttX-7.22 Release Notes
------------------------

The 122nd release of NuttX, Version 7.22, was made on September 9, 2017,
and is available for download from the Bitbucket.org website.  Note
that release consists of two tarballs:  nuttx-7.22.tar.gz and
apps-7.22.tar.gz.  These are available from:

    https://bitbucket.org/nuttx/nuttx/downloads
    https://bitbucket.org/nuttx/apps/downloads

Both may be needed (see the top-level nuttx/README.txt file for build
information).

Additional new features and extended functionality:

    * Core OS:

      - pthreads:  Move functions from sched/pthreads to libc/pthreads.  These
        functions just coordinate other OS interface calls but are not a
        fundamental OS interfaces and, hence, do not belong within the OS:
        pthread_yield(), pthread_once(), pthread_cond_init(),
        pthread_cond_destroy(), pthread_barrier_init(),
        pthread_barrier_destroy(), and pthread_barrier_wait().
      - Add power-related debug output.

    * File Systems/Block and MTD Drivers

      - RAMTRON:  Add support for splitting block writes in chunks.  Some
        Re-RAMs like MB85AS4MT have a write buffer size limitation.  From
        Boris Astardzhiev.
      - MTD: Add driver for Macronix QuadSPI flash memory.  From Simon Piriou.

    * Graphics/Display Drivers:

      - SSD1306 LCD Driver:  (1) Separate lcd_dev_s setup to separate object.
        g_oleddev takes 1 KiB because framebuffer and was allocated to .data
        section because of lcd_dev_s function pointer setup. Move lcd_dev_s
        setup out, so that g_oleddev goes to .bss and avoid wasting ROM. (2)
        Fix memory corruption caused by ssd1306_getrun(). ssd1306_getrun was
        writing one extra byte (with value 0) past target buffer when pixlen
        is multiple of 8. When pixlen was not multiple of 8, last byte of
        buffer was fully cleared, instead of modifying only the (pixlen % 8)
        bits of last byte.  (3) Add support for board power control.
        ThingseeOne has regulator for controlling display power on/off.  Patch
        adds support for board based power control to SSD1306 driver. (4) Add
        DD-12864WO-4A/SSD1309 support to SSD1306 driver. From Jussi Kivilinna.

    * Networking/Network Drivers:

      - Sockets: Support listening sockets in the getsockname() function.
        From Roland Takacs.
      - IP Forwading:  At the IP level, network may be configured to forward
        IP packets that are not destined for the target through a different
        network device, decrementing the packet TTL.
      - IP forwarding:  Add optional support to forward broadcast and
        multicast packets.  Add missing ICMP support.
      - ICMPv6:  Add 6LoWPAN and IP forwarding support.
      - ICMPv6:  Support source link-layer address option in RA.  From
        Masayuki Ishikawa.
      - TUN Driver: Add definitions that will permit TUN-only networking.
      - Socket I/F:  Created a socket interface used to provide socket support.
        Each address family has an interface that describes how to perform
        socket operations on that address family.  Currently only a couple of
        methods are defined in the socket interface call table
      - Remove CONFIG_NET_MULTILINK.  This increases code size by a little,
        but greatly reduces the complexity of the network code.
      - Network procfs:  Add support for routing tables at proc/net/route.
      - Network procfs:  Add support for network procfs statistics for the
        PF_IEEE802154 address family.
      - Network Driver Backlog:  Remove driver based backlog support.  This
        affects the entire network, but is used by only one driver.  The only
        supported RX backlog is now via common read-ahead buffering.

    * Wireless Networking/Wireless Drivers:

      - IEEE 802.15.4 MAC / MRF24J60 Driver:  Extensive updates for
        association/beacon-enabled networks.  From Anthony Merlino.
      - IEEE 802.15.4 MAC / MRF24J60 Driver:  Hook in setdevmode from newly
        added radio attribute setting.  From Anthony Merlino.
      - IEEE 802.15.4 MAC: Supports get request for coordinator address.  From
        Anthony Merlino.
      - IEEE 802.15.4 MAC: Notify radio layer of changes in devmode.  From
        Anthony Merlino.
      - IEEE 802.15.4:  Add special attribute that can be used to perform a
        regdump of the radio.  From Anthony Merlino.
      - IEEE 802.15.4 loopback driver:  Better simulation addressing: short
        and extended addresses, panid, and IP address conversion.
      - IEEE 802.15.4 Network Driver:  Add logic to setup the network mask,
        update the MAC-based IPv6 addressing when the network is brought up.
        The idea is that addressing changes are supposed to occur only while
        the network is down but won't take effect until the network is up
        again.
      - PktRadio:  Add an infrastructure to support networking on generic
        (non-IEEE 802.15.4) packet radios.
      - PktRadio Loopback Driver:  Add a PktRadio loopback network driver to
        testing testing with 6LoWPAN and PktRadios on the simulator.
      - Spirit Network Driver:  The Spirit1 radio (SPSGRF-915) is the first
        generic PktRadio Network driver.  Based on STMicros STack packets
        with 8-bit addressing.  We need to use the STack packets in order to
        provide the source address and automatic ACKing.
      - Network procfs:  Fix so that PktRadio address are shown correctly.
      - Networking:  Add support for some packet radio IOCTL commands.
      - 6LoWPAN:  Added handling for TCP and ICMPv6 packets.
      - 6LoWPAN:  Add configurable support for 6LoWPAN star topology.  With
        this change, the endpoints which are the 'points' of the star will
        forward all traffic to the coordinator.  The coordinator is assumed to
        be the 'hub' of the star.  This function also used IPv6 forwarding.
      - 6LoWPAN:  The original, Contiki-based design used only a single buffer
        for reassemblying larger packets.  This could be a problem issue for
        hub configurations which really need the capability concurrently
        reassemble multiple incoming streams concurrently. These was also a
        design issue in that the reassembly buffer could be corrupted by
        outgoing packets.  The design was extended to support multiple
        reassembly buffers, each associated with the reassembly tag and source
        address.  This assures that there can be be no corruption of the
        reassembly once it has started.
      - 6LoWPAN PktRadio:  Now radio agnostic.  All IEEE 802.15.4 dependencies
        have been removed or isolated so that 6LoWPAN can be used with any
        kind of packet radio.  This involved things like:  (1) generalizing
        the representation of radio MAC meta-data,  (2) changes to handle
        variable-length radio addresses,  (3) removal of all explicit IEEE
        802.15.4 types, references, and interfaces, (4) a new radio driver
        interface to return 'capabilities' of the drvier.
      - ICMPv6:  Update so that ICMPv6 can be used with 6LoWPAN.
      - IPv6 Neighbor:  Update table format to support IEEE 802.15.4 MAC
        addresses.
      - PF_IEEE802154 Address Family:  Add support for the PF_IEEE802154
        address family socket type. This socket is similar to the PF_PACKET,
        "raw" packet address family except that:  (1) it supports only
        SOCK_DRAM, not SOCK_RAW, and (2) works only with IEEE 802.15.4
        MAC-based radios.  This address family permits simple access to IEEE
        802.15.4 IOCTLs and frame-level network transfers.

    * Other Common Device Drivers:

      - Dynamically configurable USB composite devices:  We developed a huge
        Changeset over a year ago to make USB Composite configuration
        dynamical and be able to instantiate the CDC/ACM multiple times inside
        this device.  We use this feature to switch between one in typical USB MSC + CDC/ACM configuration and up to three CDCACMs dynamically.
        I've changed the interface for some USB-Functions to receive also the
        dynamic configuration.  From Frank Benkert.
      - Franks' change remained on a branch until all issues were resolved.
        the current version in Master is complete and ready for use.
      - power:  battery_charger: add ioctl for charging input current.  From
        Juha Niskanen.
      - SMPS driver:  Add generic upper-half driver for SMPS.  From Mateusz
        Szafoni.
      - LED Driver:  Add support for inverted LEDS.  From Jeff.
      - LED Driver:  Add lightness correction for RGB LED driver.  From Jeff.
      - LTC4151 Driver:  Add driver for LTC4151 current and voltage monitor.
        From Giorgio Groß.
      - Serial TERMIOS:  tcdrain() implementation based on a new term ioctl.
        From Sebastien Lorquet.
      - Serial TERMIOS:  Add support for TCFLUSH.  From Sebastien Lorquet.
      - syslog:  Add option to use the CLOCK_MONOTONIC for time stamping. From
        Jussi Kivilinna.
      - HC-SR04 Driver:  Add support to HC-SR04 distance sensor.  From Alan
        Carvalho de Assis.
      - COMP Driver:  Add poll support.  From Pekka Ervasti.
      - BQ2429X Driver: add driver for TI BQ2429X battery charger.  From Juha
        Niskanen.
      - ADC Driver:  Add poll support.  From Juha Niskanen.
      - BCH Driver:  Add poll support.  From Jussi Kivilinna.
      - RTC Driver:  Extend the RTC framework with an alarm read ioctl
        (RTC_RD_ALARM).  Through it consumer could get configuration settings
        about previously scheduled hardware alarms (active status, hours,
        minutes, seconds).  From Boris Astardzhiev.

    * Simulation

      - sim/ipforward:  Add an IP forwarding configuration using TUN devices
        and apps/examples/tun.
      - Console:  Add non blocking read to devconsole driver.  From Simon
        Piriou.
      - Networking:  Poll for TX frames to speed up driver.  From Simon Piriou.
      - pf_ieee802154:  Add configuration for testing PF_IEEE802154 address
        family sockets.
      - ARM Simulator:  Adds necessary functionality to build Simulator under
        ARM Linux. Tested only on Raspberry3. Currently setjmp/longjmp do not
        save/restore floating point registers.  From Nickolay Semyonov.

    * MicroChip/Atmel SAML21 Drivers:

      - SAML21 I2C driver.  Developed for and contributed with permissin from
        Filament company.  From Alan Carvalho de Assis.
      - SAMD/L21 USB Driver:  Add a USB driver.  Developed for Filament Inc.
        by Offcode, LTD.  From Janne Rosberg.

    * MicroChip/Atmel SAMv7 Boards:

      - SAMV71-XULT:  Add support for the MRF24J40 radio and create a
        mrf24j40-starhub configuration.
      - SAME70-Xplained:  Add MRF24J40 support.

    * NXP Freescale Kinetis Drivers:

      - Kinetis USB Improvements:  usbdev clean up ensuring proper use of HW.
        Rework suspend and resume logic so they perform properly.  Made attach
        and detach functions optional. As they do not make sense for a bus
        powered device.  From David Sidrane.
      - Kinetis SPI driver:  From David Sidrane.
      - Kinetis:  I2C driver added I2C3, reference counting and reset.
        Refactored the driver to support reference counting and reset added
        I2C3. From David Sidrane.
      - Kinetis RTC:  Implementation of the alarm read function.

    * NXP Freescale Kinetis Boards:

      - configs/teensy-3.x USB:  Define USBOTG-FS Read from FLASH access in
        board config.  Allow the board config to define the USBOTG-FS to have
        Read access to FLASH.  From David Sidrane.
      - configs/teensy-3.x:  Removed call to khci_usbattach.  The call is not
        need by the driver if CONFIG_USBDEV_BUSPOWERED=y.  On a USB powered device if we are running we are attached.  From David Sidrane.
      - freedom-k66f:  Use SPI driver.  Initalize SPI1 on connector J6. No
        real use, as of yet.  From David Sidrane.

    * NXP Freescale LPC43xx:

      - LPC43xx:  Modify up_allocate_(k)heap() to support PROTECTED mode. From
        Alan Carvalho de Assis.

    * NXP Freescale LPC4xx Boards:

      - configs/Bambino:  Add protected mode configuration to Bambino board.
        From Alan Carvalho de Assis.

    * On Semiconductor LC823450

      - LC823450: Initial support for ON Semiconductor LC823450. From Masayuki
        Ishikawa.
      - LC823450: eMMC/SD and USB support for LC823450.  From Masayuki Ishikawa.

    * On Semiconductor LC823450 Boards

      - LC823450-XGEVK:  LC823450-XGEVK board support.  From Masayuki
        Ishikawa.
      - LC823450-XGEVK:  Add eMMC/SD and USB support.  From Masayuki Ishikawa.

      * STMicro STM32:

      - STM32 L4:  Add support for the STM32L475 family.
      - STM32 L4 RCC:  Enable ADC clock source.  From Juha Niskanen.
      - STM32:  Allow clock frequencies > 168 Mhz on stm32f427/429.  We need
        to enable the power overdrive for this case.  This change allows the
        required bits to be set in proper sequence.  It also modifies the
        local register access operations to allow more than 16-bit registers.
        From Sebastien Lorquet .
      - STM32 F4:  Add support for STM32F433RC.  From Alan Carvalho de Assis.
      - STM32 F7:  Add new configuration option for enabling flash ART
        Accelerator and flash prefetcher.  From Jussi Kivilinna.

    * STMicro STM32 Drivers:

      - STM32 TIM:  Add the set counter function for stm32 timers.  From
        Sergey Ustinov.
      - STM32 HRTIM:  Update HRTIM definitions. Add HRTIM driver.  From
        Mateusz Szafoni.
      - STM32 HRTIM:  Add HRTIM character driver.  From Mateusz Szafoni.
      - STM32 HRTIM:  Fix DAC triggers configuration, Add missing master timer
        logic, enable DAC triggering.  From Mateusz Szafoni.
      - STM32 HRTIM:  Add DMA configuration. From Mateusz Szafoni.
      - STM32 HRTIM:  Add burst mode configuration.  From Mateusz Szafoni.
      - STM32 RTC:  Port Boris Astardzhiev's RTC change for STM32L4 to STM32.
      - STM32 DAC:  Add support for HRTIM triggering.  Separate dma buffer
        configuration for channels.  From Mateusz Szafoni.
      - STM32 DAC:  Conditional logic for timer triggering, fix TSEL
        configuration when HRTIM, DMA request remapping, Add DMA buffers
        initialization logic.  From Mateusz Szafoni.
      - STM32 DAC:  Support external triggering for DMA transfer.  From Mateusz
        Szafoni.
      - STM32 L1 TIM:  Add base address for TIM11.  From Juha Niskanen.
      - STM32 F4 FLASH:  Enable/disable the flash write protection on any
        sector.  I have verified it to work on the STM32 F427.  From Sebastien
        Lorquet.
      - STM32 F4 Clocking:  To use an external oscillator module (not just a
        crystal) with the STM32F4, one needs to enable the HSEBYP bit in the
        RCC_CR register. This change allows an integrator to define
        STM32_RCC_CR_HSEBYP in their board.h file if they want this
        configuration.  From Jeff.
      - STM32 F4 USB:  I'm working on bringing up USB full-speed support on
        STM32F405.  My board does not include a USB power switch, VBus
        sensing, over current detection, or ID pin.  This commit add a
        config STM32_OTGFS_VBUS_ CONTROL which lets us selectively disable
        VBus sensing and control.  I also sneaked in a change to disable the
        configgpio call for the ID pin, which is only used in OTG mode which
        isn't supported yet.  The only pins that need to be initialized should
        be OTGFS_DP and OTGFS_DM.  From Jeff.
      - STM32 FLASH:  Add CONFIG_STM32_STM32F469 support. From David Sidrane.
      - STM32 COMP:  Add default INM configuration and some missing COMP
        1,3,5,7 code.  From Mateusz Szafoni.
      - STM32 F33:  Add missing SYSCFG CFGR3 definitions.  From Mateusz Szafoni.
      - STM32 L4 Serial: Allow configuring Rx DMA buffer size.  From Juha
        Niskanen.
      - STM32 L4 COMP:  Input minus pin extended selection.  From Juha Niskanen.
      - STM32 L4 COMP:  Bind to upper half comp driver.  From Pekka Ervasti.
      - STM32 L4 DAC:  Port from STM32.  Add ADC register definitions.  From
        Juha Niskanen.
      - STM32 L4 DAC:  Add option for routing DAC output to ADC.  Actually
        write something to the DAC DMA buffer.  From Juha Niskanen.
      - STM32 L4 DAC:  Separate DMA buffer configuration for channels. From
        Juha Niskanen.
      - STM32 L4 ADC:  Implement peripheral.  From Juha Niskanen.
      - STM32 F7:  Definitions for I2C4, SDMMC2.  Adapted RAM start / size to
        internal SRAM.  From Titus von Boxberg.
      - STM32 F7 I2C4:  I2C4_SDA can also be on GPIO PB7.  From Titus von
        Boxberg.
      - STM32 F7 LTDC:  Option for DSI output, inconsistency: the stm32f746
        does not feature a DSI interface.  compilable with LTDC_INTERFACE and
        LTDC_USE_DSI.  From Titus von Boxberg.
      - STM32 F7 Clocking:  Added functions for DSI clock source selection.
        From Titus von Boxberg.
      - STM32 F7 Clocking:  Enable APB2 DSI clock.  From Titus von Boxberg.
      - STM32 F7 LTDC:  No board specific dithering values used; corrected
        dithering init.  Corrected LIPOS/LIPCR calculation.  Change only
        polarity bits in LTDC_GCR.  From Titus von Boxberg.
      - STM32 F7 Reset:  Added function for reset.  From Titus von Boxberg.
      - STM32 F7 DMA:  DMA add dcache alignment check in stm32_dmacapable.  In
        the case dcache write-buffed mode is used (not write-through) buffer
        alignment is required for DMA transfers because  a)
        arch_invalidate_dcache could lose buffered writes data and b)
        arch_flush_dcache could corrupt adjacent memory if the maddr and the
        mend+1, the next next address are not on ARMV7M_DCACHE_LINESIZE
        boundaries.  From David Sidrane.
      - STM32 F7 SDMMC: SDMMC remove widebus limitation on DMA.  There is no
        documantation for the STM32F7 that limits DMA on 1 bit vrs 4 bit
        mode.  From David Sidrane.
      - STM32 F7 SDMMC: SDMMC add dcache alignment check in
        dma{recv|send}setup. In the case where CONFIG_SDIO_PREFLIGHT is not
        used.
      - STM32 F7 RTC: Port Boris Astardzhiev's RTC change for STM32L4 to
        STM32F7.

    * STMicro STM32 Boards:

      - STM32F103-Minimum:  Add GPIO device driver example.  From Alan
        Carvalho de Assis.
      - STM32F103-Minimum: Add small hello example for  STM32F103-Minimum
        board.  From Alan Carvalho de Assis.
      - STM32F103-Minimum: Add support for SmartFS on Winbond W25 SPI NOR
        Flash.  From Alan Carvalho de Assis.
      - STM32F103-Minimum: (1) Enable CONFIG_MTD_PARTITION in Kconfig if flash
        partition is enabled and (2) Update the README.txt file with info
        needed to get SmartFS working.  From Alan Carvalho de Assis.
      - Nucleo-F334R8:  Add HRTIM initialization.  From Mateusz Szafoni.
      - Nucleo-F334R8:  UART2 is default serial port (STLINK Virtual Port).
        From Mateusz Szafoni.
      - Clicker2-STM32:  Add a configuration that was used with the MRF24J60
        for 6loWPAN testing.
      - Clicker2-STM32:  Allow both IEEE 802.15.4 MAC character and network
        devices to be registered.
      - Clicker2-STM32:  Add configurations to support the endpoint and hub
        roles in a star topology.
      - Clicker2-STM32:  Add support for per-function-call stack checking.
        From Anthony Merlino.
      - Clicker2-STM32:  Configure EDBG SPI CS just to make that it is
        disabled.
      - STM32F4 Discovery: Add logic to register the button driver and the
        user led driver if so configured.  From Jan Pobrislo.
      - STM32F4-Discovery:  Add a configuration for testing libc++.  From Alan
        Carvalho de Assis.
      - B-L475E-IOT01A:  Add support for the STMicro B-L475E-IOT01A board.
        From Simon Piriou.
      - B-L475E-IOT01A: Add support for the SPSRGF/Spirit1 radio module.  Add
        a configuration for testing sprit radio.
      - B-L475E-IOT01A:  Add configurations to support a star topology.
      - B-L475E-IOT01A: add basic support for external Macronix QuadSPI flash
        memory.  From Simon Piriou.
      - B-L475E-IOT01A:  Enable UDP broadcast test in the spirit-starhub
        configuration.
      - STM32F334-DISCO:  Add STM32F334-DISCO basic support.  From Mateusz
        Szafoni.
      - STM32F746-Disco:  Add ADC3 support.  From Ivan Ucherdzhiev.
      - STM32L476-Disco:  Add a knsh configuration that may be used to test
        the PROTECTED build mode.
      - STM32F769I-DISCO:  Initial port to STM32F769I-DISCO.  From Titus von
        Boxberg.

    * C Library/Header Files:

      - Move TUN ioctl command to include/nuttx/net/ioctl.h so that it will
        always be unique.
      - Math Library:  Port gamma() and lgamma() from FreeBSD to NuttX.  From
        Alan Carvalho de Assis.
      - C++: Compilation with recent C++ compiler needs an overloaded delete
        operator that includes a size_t size argument.  New sized delete
        operators are only for C++14 and above.

    * Build/Configuration System:

      - Initial clang compile.  From Goran Mekic.
      - Add CLANG definitions in Kconfig and Toolchain.defs.
      - drivers/wireless/ieee802154:  Moved radios to individual
        sub-directories.  From Anthony Merlino.
      - Makefile.unix: Add savedefconfig target.  From Gwenhael Goavec-Merou.
      - Add Gwenhael's change to Makefile.win and update README.txt to
        described the new make target.
      - All defconfig files are now in the compressed format created with
        'make savedefconfig.'  The original .config file can be reconstituted
        using 'make olddefconfig.'
      - Build System:  It is no longer necessary to have a unique Make.defs
        file for each configuration.  A board may share a common Make.defs
        file in the scripts directory.  Duplicate Make.defs files removed;
        common Make.defs file moved to the scripts/ sub-directory for each
        board.
      - Networking: Move INET socket interface out of net/sockets to its own
        directory net/inet.

    * Tools:

      - testbuild.sh:  Added -x to fail build on errors for continous
        integration (CI).  On CI we want to know ASAP of a failure.  From
        David Sidrane.
      - Improve configure.sh behavior:  (1) enable to call from top directory.
        (2) enable to designate direct path for config.  (3) install .gdbinit
        if the target has.  From Hidetaka Takano.
      - Update tools/configure.c to same functionality as configure.sh.  Add
        an array of optional file names.  Currently, .gdbinit is the only
        optional file but other things like IDE-specific project files might
        need to be copied as well.
      - tools/configure.sh will now copy Eclipse project files if they are
        present in the board directory file.
      - Update configure.sh, configure.bat, configure.c:  With compressed
        format, part of the installation requires that we run 'make
        olddefconfig' to restore the uncompressed defconfig format.  Also,
        while I was at it, I also added options to select host platform on
        configure command line.
      - tools/refresh.sh:  Now runs make savedefconfig before copying the new
        defconfig file in place;  Also, added a new option --defaults.  Since
        the number of defaults that you now have to answer is so large, the
        option lets you just accept the default values.  So it works just like
        --silent but still prompts you for the decision to save or discard the
        new defconfig file.
      - tools/refresh.sh:  Update so that it can find the Make.defs file in
        the new location.

    * NSH: apps/nshlib:

      - NSH Library:  Add a Telnetd command.  This is needed when network
        initialization is deferred.  In that case, telnet daemon cannot be
        started until the network is finally initialized.  The telnetd command
        was added just for that case:  So that the telnet daemon can be
        started from the NSH command line after the network is configured.
      - NSH Library:  Misc changes needed for PktRadio support.
      - NSH Library:  Extend ifconfig command so that it can set variable
        length packet radio addresss.
      - NSH Library:  Update addroute and delroute command.  The would support either
        IPv4 or IPv6, but not both.  Allow expression of the netmask in IPv4 CIDR or
        IPv6 slash notation.  This really reduces the pain of using the commands,
        especially for IPv6.
      - NSH Library: Add a route command that will dump the content of routing table.

    * Examples/Tests: apps/examples:

      - examples/udp: Add configurable network device name; Add option to
        suppress network initialization which is not needed if started by NSH
        or for 6LoWPAN.
      - examples/udp:  Fix registration as a built-in program; Change some
        naming to make room for a second target.  Current one endpoint is the
        target and one is the host.  This will (eventually) allow two targets
        to be both endpoints of the test.  Change build so that both server
        and client can be on a target, rather than one on the target one on
        the host PC.  Server IP address may not be provided on the command line.