rt-thread-stm32f072/rt-thread/components/net/lwip/lwip-2.0.3/doc/doxygen/main_page.h

133 lines
4.7 KiB
C
Raw Blame History

This file contains invisible Unicode characters!

This file contains invisible Unicode characters that may be processed differently from what appears below. If your use case is intentional and legitimate, you can safely ignore this warning. Use the Escape button to reveal hidden characters.

/**
* @defgroup lwip lwIP
*
* @defgroup infrastructure Infrastructure
*
* @defgroup callbackstyle_api Callback-style APIs
* Non thread-safe APIs, callback style for maximum performance and minimum
* memory footprint.
*
* @defgroup sequential_api Sequential-style APIs
* Sequential-style APIs, blocking functions. More overhead, but can be called
* from any thread except TCPIP thread.
*
* @defgroup addons Addons
*
* @defgroup apps Applications
*/
/**
* @mainpage Overview
* @verbinclude "README"
*/
/**
* @page upgrading Upgrading
* @verbinclude "UPGRADING"
*/
/**
* @page changelog Changelog
* @verbinclude "CHANGELOG"
*/
/**
* @page contrib How to contribute to lwIP
* @verbinclude "contrib.txt"
*/
/**
* @page pitfalls Common pitfalls
*
* Multiple Execution Contexts in lwIP code
* ========================================
*
* The most common source of lwIP problems is to have multiple execution contexts
* inside the lwIP code.
*
* lwIP can be used in two basic modes: @ref lwip_nosys (no OS/RTOS
* running on target system) or @ref lwip_os (there is an OS running
* on the target system).
*
* Mainloop Mode
* -------------
* In mainloop mode, only @ref callbackstyle_api can be used.
* The user has two possibilities to ensure there is only one
* exection context at a time in lwIP:
*
* 1) Deliver RX ethernet packets directly in interrupt context to lwIP
* by calling netif->input directly in interrupt. This implies all lwIP
* callback functions are called in IRQ context, which may cause further
* problems in application code: IRQ is blocked for a long time, multiple
* execution contexts in application code etc. When the application wants
* to call lwIP, it only needs to disable interrupts during the call.
* If timers are involved, even more locking code is needed to lock out
* timer IRQ and ethernet IRQ from each other, assuming these may be nested.
*
* 2) Run lwIP in a mainloop. There is example code here: @ref lwip_nosys.
* lwIP is _ONLY_ called from mainloop callstacks here. The ethernet IRQ
* has to put received telegrams into a queue which is polled in the
* mainloop. Ensure lwIP is _NEVER_ called from an interrupt, e.g.
* some SPI IRQ wants to forward data to udp_send() or tcp_write()!
*
* OS Mode
* -------
* In OS mode, @ref callbackstyle_api AND @ref sequential_api can be used.
* @ref sequential_api are designed to be called from threads other than
* the TCPIP thread, so there is nothing to consider here.
* But @ref callbackstyle_api functions must _ONLY_ be called from
* TCPIP thread. It is a common error to call these from other threads
* or from IRQ contexts. Ethernet RX needs to deliver incoming packets
* in the correct way by sending a message to TCPIP thread, this is
* implemented in tcpip_input().
* Again, ensure lwIP is _NEVER_ called from an interrupt, e.g.
* some SPI IRQ wants to forward data to udp_send() or tcp_write()!
*
* 1) tcpip_callback() can be used get called back from TCPIP thread,
* it is safe to call any @ref callbackstyle_api from there.
*
* 2) Use @ref LWIP_TCPIP_CORE_LOCKING. All @ref callbackstyle_api
* functions can be called when lwIP core lock is aquired, see
* @ref LOCK_TCPIP_CORE() and @ref UNLOCK_TCPIP_CORE().
* These macros cannot be used in an interrupt context!
* Note the OS must correctly handle priority inversion for this.
*/
/**
* @page bugs Reporting bugs
* Please report bugs in the lwIP bug tracker at savannah.\n
* BEFORE submitting, please check if the bug has already been reported!\n
* https://savannah.nongnu.org/bugs/?group=lwip
*/
/**
* @defgroup lwip_nosys Mainloop mode ("NO_SYS")
* @ingroup lwip
* Use this mode if you do not run an OS on your system. \#define NO_SYS to 1.
* Feed incoming packets to netif->input(pbuf, netif) function from mainloop,
* *not* *from* *interrupt* *context*. You can allocate a @ref pbuf in interrupt
* context and put them into a queue which is processed from mainloop.\n
* Call sys_check_timeouts() periodically in the mainloop.\n
* Porting: implement all functions in @ref sys_time, @ref sys_prot and
* @ref compiler_abstraction.\n
* You can only use @ref callbackstyle_api in this mode.\n
* Sample code:\n
* @include NO_SYS_SampleCode.c
*/
/**
* @defgroup lwip_os OS mode (TCPIP thread)
* @ingroup lwip
* Use this mode if you run an OS on your system. It is recommended to
* use an RTOS that correctly handles priority inversion and
* to use @ref LWIP_TCPIP_CORE_LOCKING.\n
* Porting: implement all functions in @ref sys_layer.\n
* You can use @ref callbackstyle_api together with @ref tcpip_callback,
* and all @ref sequential_api.
*/
/**
* @page raw_api lwIP API
* @verbinclude "rawapi.txt"
*/