From fa046601a54ddf2137048f11594ed7d72ede995a Mon Sep 17 00:00:00 2001 From: Gareth McMullin Date: Sat, 28 Feb 2015 20:50:10 -0800 Subject: Add exception handling mechanism and raise exception on low-level comms failure. --- src/include/exception.h | 74 +++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 74 insertions(+) create mode 100644 src/include/exception.h (limited to 'src/include/exception.h') diff --git a/src/include/exception.h b/src/include/exception.h new file mode 100644 index 0000000..180398d --- /dev/null +++ b/src/include/exception.h @@ -0,0 +1,74 @@ +/* + * This file is part of the Black Magic Debug project. + * + * Copyright (C) 2015 Black Sphere Technologies Ltd. + * Written by Gareth McMullin + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +/* Exception handling to escape deep nesting. + * Used for the case of communicaiton failure and timeouts. + */ + +/* Example usage: + * + * volatile struct exception e; + * TRY_CATCH (e, EXCEPTION_TIMEOUT) { + * ... + * raise_exception(EXCEPTION_TIMEOUT, "Timeout occurred"); + * ... + * } + * if (e.type == EXCEPTION_TIMEOUT) { + * printf("timeout: %s\n", e.msg); + * } + */ + +/* Limitations: + * Can't use break, return, goto, etc from inside the TRY_CATCH block. + */ + +#ifndef __EXCEPTION_H +#define __EXCEPTION_H + +#include +#include + +#define EXCEPTION_ERROR 0x01 +#define EXCEPTION_TIMEOUT 0x02 +#define EXCEPTION_ALL -1 + +struct exception { + uint32_t type; + const char *msg; + /* private */ + uint32_t mask; + jmp_buf jmpbuf; + struct exception *outer; +}; + +extern struct exception *innermost_exception; + +#define TRY_CATCH(e, type_mask) \ + (e).type = 0; \ + (e).mask = (type_mask); \ + (e).outer = innermost_exception; \ + innermost_exception = (void*)&(e); \ + if (setjmp(innermost_exception->jmpbuf) == 0) \ + for (;innermost_exception == &(e); innermost_exception = (e).outer) + +void raise_exception(uint32_t type, const char *msg); + +#endif + -- cgit v1.2.3