/* * Copyright (c) 2001-2004 Swedish Institute of Computer Science. * All rights reserved. * * 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. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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. * * This file is part of the lwIP TCP/IP stack. * * Author: Adam Dunkels * */ #ifndef __LWIP_SYS_H__ #define __LWIP_SYS_H__ #include "lwip/opt.h" #ifdef __cplusplus extern "C" { #endif #if NO_SYS /* For a totally minimal and standalone system, we provide null definitions of the sys_ functions. */ typedef u8_t sys_sem_t; typedef u8_t sys_mbox_t; struct sys_timeo {u8_t dummy;}; #define sys_init() #define sys_timeout(m,h,a) #define sys_untimeout(m,a) #define sys_sem_new(c) c #define sys_sem_signal(s) #define sys_sem_wait(s) #define sys_sem_wait_timeout(s,t) #define sys_arch_sem_wait(s,t) #define sys_sem_free(s) #define sys_mbox_new(s) 0 #define sys_mbox_fetch(m,d) #define sys_mbox_tryfetch(m,d) #define sys_mbox_post(m,d) #define sys_mbox_trypost(m,d) #define sys_mbox_free(m) #define sys_thread_new(n,t,a,s,p) #else /* NO_SYS */ /** Return code for timeouts from sys_arch_mbox_fetch and sys_arch_sem_wait */ #define SYS_ARCH_TIMEOUT 0xffffffffUL /* sys_mbox_tryfetch returns SYS_MBOX_EMPTY if appropriate. * For now we use the same magic value, but we allow this to change in future. */ #define SYS_MBOX_EMPTY SYS_ARCH_TIMEOUT #include "lwip/err.h" #include "arch/sys_arch.h" typedef void (* sys_timeout_handler)(void *arg); struct sys_timeo { struct sys_timeo *next; u32_t time; sys_timeout_handler h; void *arg; }; struct sys_timeouts { struct sys_timeo *next; }; /* sys_init() must be called before anthing else. */ void sys_init(void); /* * sys_timeout(): * * Schedule a timeout a specified amount of milliseconds in the * future. When the timeout occurs, the specified timeout handler will * be called. The handler will be passed the "arg" argument when * called. * */ void sys_timeout(u32_t msecs, sys_timeout_handler h, void *arg); void sys_untimeout(sys_timeout_handler h, void *arg); struct sys_timeouts *sys_arch_timeouts(void); /* Semaphore functions. */ sys_sem_t sys_sem_new(u8_t count); void sys_sem_signal(sys_sem_t sem); u32_t sys_arch_sem_wait(sys_sem_t sem, u32_t timeout); void sys_sem_free(sys_sem_t sem); void sys_sem_wait(sys_sem_t sem); int sys_sem_wait_timeout(sys_sem_t sem, u32_t timeout); /* Time functions. */ #ifndef sys_msleep void sys_msleep(u32_t ms); /* only has a (close to) 1 jiffy resolution. */ #endif #ifndef sys_jiffies u32_t sys_jiffies(void); /* since power up. */ #endif /* Mailbox functions. */ sys_mbox_t sys_mbox_new(int size); void sys_mbox_post(sys_mbox_t mbox, void *msg); err_t sys_mbox_trypost(sys_mbox_t mbox, void *msg); u32_t sys_arch_mbox_fetch(sys_mbox_t mbox, void **msg, u32_t timeout); #ifndef sys_arch_mbox_tryfetch /* Allow port to override with a macro */ u32_t sys_arch_mbox_tryfetch(sys_mbox_t mbox, void **msg); #endif /* For now, we map straight to sys_arch implementation. */ #define sys_mbox_tryfetch(mbox, msg) sys_arch_mbox_tryfetch(mbox, msg) void sys_mbox_free(sys_mbox_t mbox); void sys_mbox_fetch(sys_mbox_t mbox, void **msg); /* Thread functions. */ sys_thread_t sys_thread_new(char *name, void (* thread)(void *arg), void *arg, int stacksize, int prio); #endif /* NO_SYS */ /** Returns the current time in milliseconds. */ u32_t sys_now(void); /* Critical Region Protection */ /* These functions must be implemented in the sys_arch.c file. In some implementations they can provide a more light-weight protection mechanism than using semaphores. Otherwise semaphores can be used for implementation */ #ifndef SYS_ARCH_PROTECT /** SYS_LIGHTWEIGHT_PROT * define SYS_LIGHTWEIGHT_PROT in lwipopts.h if you want inter-task protection * for certain critical regions during buffer allocation, deallocation and memory * allocation and deallocation. */ #if SYS_LIGHTWEIGHT_PROT /** SYS_ARCH_DECL_PROTECT * declare a protection variable. This macro will default to defining a variable of * type sys_prot_t. If a particular port needs a different implementation, then * this macro may be defined in sys_arch.h. */ #define SYS_ARCH_DECL_PROTECT(lev) sys_prot_t lev /** SYS_ARCH_PROTECT * Perform a "fast" protect. This could be implemented by * disabling interrupts for an embedded system or by using a semaphore or * mutex. The implementation should allow calling SYS_ARCH_PROTECT when * already protected. The old protection level is returned in the variable * "lev". This macro will default to calling the sys_arch_protect() function * which should be implemented in sys_arch.c. If a particular port needs a * different implementation, then this macro may be defined in sys_arch.h */ #define SYS_ARCH_PROTECT(lev) lev = sys_arch_protect() /** SYS_ARCH_UNPROTECT * Perform a "fast" set of the protection level to "lev". This could be * implemented by setting the interrupt level to "lev" within the MACRO or by * using a semaphore or mutex. This macro will default to calling the * sys_arch_unprotect() function which should be implemented in * sys_arch.c. If a particular port needs a different implementation, then * this macro may be defined in sys_arch.h */ #define SYS_ARCH_UNPROTECT(lev) sys_arch_unprotect(lev) sys_prot_t sys_arch_protect(void); void sys_arch_unprotect(sys_prot_t pval); #else #define SYS_ARCH_DECL_PROTECT(lev) #define SYS_ARCH_PROTECT(lev) #define SYS_ARCH_UNPROTECT(lev) #endif /* SYS_LIGHTWEIGHT_PROT */ #endif /* SYS_ARCH_PROTECT */ /* * Macros to set/get and increase/decrease variables in a thread-safe way. * Use these for accessing variable that are used from more than one thread. */ #ifndef SYS_ARCH_INC #define SYS_ARCH_INC(var, val) do { \ SYS_ARCH_DECL_PROTECT(old_level); \ SYS_ARCH_PROTECT(old_level); \ var += val; \ SYS_ARCH_UNPROTECT(old_level); \ } while(0) #endif /* SYS_ARCH_INC */ #ifndef SYS_ARCH_DEC #define SYS_ARCH_DEC(var, val) do { \ SYS_ARCH_DECL_PROTECT(old_level); \ SYS_ARCH_PROTECT(old_level); \ var -= val; \ SYS_ARCH_UNPROTECT(old_level); \ } while(0) #endif /* SYS_ARCH_DEC */ #ifndef SYS_ARCH_GET #define SYS_ARCH_GET(var, ret) do { \ SYS_ARCH_DECL_PROTECT(old_level); \ SYS_ARCH_PROTECT(old_level); \ ret = var; \ SYS_ARCH_UNPROTECT(old_level); \ } while(0) #endif /* SYS_ARCH_GET */ #ifndef SYS_ARCH_SET #define SYS_ARCH_SET(var, val) do { \ SYS_ARCH_DECL_PROTECT(old_level); \ SYS_ARCH_PROTECT(old_level); \ var = val; \ SYS_ARCH_UNPROTECT(old_level); \ } while(0) #endif /* SYS_ARCH_SET */ #ifdef __cplusplus } #endif #endif /* __LWIP_SYS_H__ */