Previously, send() was somewhat soft - it only ever made one send
call to the underlying stack, so it would typically take as much data
as would fit in the buffer, and only block if it was unable to write
anything.
This is not the intent of a POSIX socket/filehandle write. It should try
to send everything if blocking, and only send less if interrupted by a
signal:
- If the O_NONBLOCK flag is clear, write() shall block the calling
thread until the data can be accepted.
- If the O_NONBLOCK flag is set, write() shall not block the thread.
If some data can be written without blocking the thread, write()
shall write what it can and return the number of bytes written.
Otherwise, it shall return -1 and set errno to [EAGAIN].
This "send all" behaviour is of slightly limited usefulness in POSIX, as
you still usually have to worry about the interruption possibility:
- If write() is interrupted by a signal before it writes any data, it
shall return -1 with errno set to [EINTR].
- If write() is interrupted by a signal after it successfully writes
some data, it shall return the number of bytes written.
But as mbed OS does not have the possibility of signal interruption, if we
strengthen send to write everything, we can make applications' lives
easier - they can just do "send(large amount)" confident that it will
all go in one call (if no errors).
So, rework to make multiple sends to the underlying stack, blocking as
necessary, until all data is written.
This change does not apply to recv(), which is correct in only blocking until
some data is available:
- If O_NONBLOCK is set, read() shall return -1 and set errno to [EAGAIN].
- If O_NONBLOCK is clear, read() shall block the calling thread until some
data becomes available.
- The use of the O_NONBLOCK flag has no effect if there is some data
available.
From C++11 and beyond string literals must be seperated by space
so that they are recongizable as seperate tokens.
Context macro in PPPCellularInterface (CTX) has been causing issues
as it was not augmented with a space from a nearby string literal.
Cellular example had build issues with IAR8, combination of define and string
as argument to send function resulted in above error. Typecasting to const char *
didn't help, hence replacing the define explicitly.
Basic TCP/UDP tests for PPP based onboard cellular modems.
Tests basic public APIs defined in CellularBase.h
A customer port must pass this test set, hence verifying their
particular implementation.
For keep supporting external APIs with the same name (supposedly there are a larger
number of users of those APIs), BufferedSerial and ATParser are being renamed.
BufferedSerial becomes UARTSerial, will complement a future USBSerial etc.
ATParser becomes ATCmdParser.
* UARTSerial moves to /drivers
* APN_db.h is moved from platform to cellular/util/.
* Original CellularInterface is restored for backward compatability (again, supposedly there
are users of that).
* A new file, CellularBase is added which will now servce as the base class for all
upcoming drivers.
* Special restructuring for the driver has been undertaken. This makes a clear cut distinction
between an on-board or an off-board implementation.
- PPPCellularInterface is a generic network interface that works with a generic FileHandle
and PPP. A derived class is needed to pass that FileHandle.
- PPPCellularInterface provides some base functionality like network registration, AT setup,
PPP connection etc. Lower level job is delegated to the derived classes and various modem
specific APIs are provided which are supposed to be overridden.
- UARTCellularInterface is derived from PPPCellularInterface. It constructs a FileHandle and
passes it back to PPPCellularInterface as well as provides modem hangupf functionality.
In future we could proive a USBInterface that would derive from PPPCellularInterface and could
pass the FileHandle back.
- OnboardCellularInterface is derived from UARTCellularInterfae and provides hooks to
the target provided implementation of onbard_modem_api.h. An off-board modem, i.e, a modem on
a shield has to override the modem_init(), modem_power_up() etc as it cannot use
onboard_modem_api.h.
GCC have not been capable enough to catch some linker errors which arose when
ethernet support for LWIP was disabled. Checks have been added to make sure that
unrefrenced code is not linked in.
nsapi_ppp glue layer is made more transparent to public cellular API. Storage of IP
addresses is removed. PPP layer already stores the addresses, so we pass the pointer back
to the upper layers.
If PPP is not used, we provide dummy functions.
* state machine corrections
* adding various standard API methods
* Addition/revision/enhancement of the nsapi_ppp glue layer
* Turning off debug by default
Mainly reutilizing code from ublox C027 support lib.
As we are using external PDP context, i.e., an external IP stack,
we will pass username and password to underlying stack running PPP.
We only support CHAP as the authentication protocol.
In case of carrier lost, we would like to inform PPP data pump.
That involved setting up link status flag down semaphores.
mbed_lwip_bringup() and mbed_lwip_bringdown() had been Ethernet specific only.
We extend these routines to support PPP as well. Currently we support only one interface
at a time. However, future enhancement to multi interface support should be trivial.
Observed during investigation of
https://github.com/ARMmbed/mbed-os/issues/4246 - DNS queries sent
the entire buffer, not just the bit filled in.
Inefficient, especially for 6LoWPAN, and a security hole - the trailing
data could be previously-used heap.
Note, the registered callback is still disabled by a call to
socket_attach. This will avoid being called after the socket is closed
unless close is called from the attached callback, which is in irq
context.
As pointed out by kjbracey-arm, the previous behaviour was broken
for sockets that started out listening.
To allow a network stack to support both NSAPI and its own options, try to make
sure the NSAPI levels don't collide with level numbers likely to be used by
network stacks.
Distinguish between socket and stack options, and tighten up documentation. Add
IP MRU stack options as an example (implementation not immediately planned for
any stack, but could be useful).
A few new error codes are added to nsapi_error_t and
support for non-blocking socket connect is added.
Nanostack's connect call will be non-blocking.
Whereas LWIP connect call is currently blocking, and it could be changed now
to be non-blocking.
During open, the socket checked the internal stack variable,
assuming it would alway be null on a socket not connected to
the network. However, when a socket is closed, the stack variable
was not updated, causing the socket to incorrectly return a
parameter error if reopened.
The simple fix was to set the stack to null on close. A non-null
stack is a predicate for a non-null socket variable, so no additional
checks are needed in socket functions.
It's currently possible to generate a socket event when a non-blocking socket is closed:
1. _pending is set to 0 in https://github.com/ARMmbed/mbed-os/blob/master/features/netsocket/TCPSocket.cpp#L22
when the socket is created.
2. close() calls event() in https://github.com/ARMmbed/mbed-os/blob/master/features/netsocket/Socket.cpp#L66
3. event() increments _pending, and since _pending is 1 it will call _callback() in https://github.com/ARMmbed/mbed-os/blob/master/features/netsocket/TCPSocket.cpp#L167
However, if send() (for example) is called, this can happen:
- send() is called and sets _pending to 0.
- when the data is sent, event() is called, which sets _pending to 1 and calls _callback().
- if close() is called at this point, there won't be an event generated for close() anymore,
since _pending will be set to 2.
Same thing for recv. Also, same thing for TCPServer and UDPSocket.
This PR changes the initial value of _pending to 1 instead of 0, so that
events are never generated for close().
Initially these assertions were added to protected simultaneous
send/recv from the same socket when similarly purposed mutexes were
removed.
However, simultaneous send/recv can still be useful for UDP if the
payload is guaranteed to be less than the MTU across the entire
connection.
set_ip_bytes() does a 16-byte memcpy from the input buffer to
the local nsapi_addr_t despite the address version.
If the address version is ipv4, the input buffer may only be
4-byte in size. This causes a out-of-bound access on the input buffer.
Signed-off-by: Tony Wu <tonywu@realtek.com>
nsapi_error_t - enum of errors or 0 for NSAPI_ERROR_OK
nsapi_size_t - unsigned size of data that could be sent
nsapi_size_or_error_t - either a non-negative size or negative error
Kevin Bracey
Kevin Gilbert
Jimmy Brisson
Hasnain Virk
adbridge
Deepika
Rob Meades
Martin Kojtal
Mika Leppänen
Russ Butler
Sam Grove
Bartek Szatkowski
Christopher Haster
Bogdan Marinescu
andreas.larsson
Tony Wu