X-Git-Url: http://git.linex4red.de/pub/USBasp.git/blobdiff_plain/c326fe96050cf80992ded7726e9222ac5305a908..cae0fa73d70f82820bd8d71c4d60b6aff8ccf3cb:/LUFA/Common/Common.h diff --git a/LUFA/Common/Common.h b/LUFA/Common/Common.h index 76144f94b..c1aa27a5f 100644 --- a/LUFA/Common/Common.h +++ b/LUFA/Common/Common.h @@ -1,21 +1,21 @@ /* LUFA Library - Copyright (C) Dean Camera, 2010. - + Copyright (C) Dean Camera, 2011. + dean [at] fourwalledcubicle [dot] com - www.fourwalledcubicle.com + www.lufa-lib.org */ /* - Copyright 2010 Dean Camera (dean [at] fourwalledcubicle [dot] com) + Copyright 2011 Dean Camera (dean [at] fourwalledcubicle [dot] com) - Permission to use, copy, modify, distribute, and sell this + Permission to use, copy, modify, distribute, and sell this software and its documentation for any purpose is hereby granted - without fee, provided that the above copyright notice appear in + without fee, provided that the above copyright notice appear in all copies and that both that the copyright notice and this - permission notice and warranty disclaimer appear in supporting - documentation, and that the name of the author not be used in - advertising or publicity pertaining to distribution of the + permission notice and warranty disclaimer appear in supporting + documentation, and that the name of the author not be used in + advertising or publicity pertaining to distribution of the software without specific, written prior permission. The author disclaim all warranties with regard to this @@ -32,9 +32,9 @@ * \brief Common library convenience macros and functions. * * This file contains macros which are common to all library elements, and which may be useful in user code. It - * also includes other common headers, such as Atomic.h, Attributes.h and BoardTypes.h. + * also includes other common code headers. */ - + /** @defgroup Group_Common Common Utility Headers - LUFA/Drivers/Common/Common.h * * Common utility headers containing macros, functions, enums and types which are common to all @@ -47,7 +47,7 @@ * * Macros for debugging use. */ - + /** @defgroup Group_BitManip Endian and Bit Macros * * Functions for swapping endianness and reversing bit orders. @@ -57,63 +57,102 @@ #define __COMMON_H__ /* Includes: */ - #include - + #include + #include + #include "Attributes.h" #include "BoardTypes.h" /* Public Interface - May be used in end-application: */ - /* Macros: */ + /* Macros: */ /** Macro for encasing other multi-statement macros. This should be used along with an opening brace * before the start of any multi-statement macro, so that the macros contents as a whole are treated * as a discrete block and not as a list of separate statements which may cause problems when used as - * a block (such as inline IF statements). + * a block (such as inline \c if statements). */ #define MACROS do /** Macro for encasing other multi-statement macros. This should be used along with a preceding closing * brace at the end of any multi-statement macro, so that the macros contents as a whole are treated * as a discrete block and not as a list of separate statements which may cause problems when used as - * a block (such as inline IF statements). + * a block (such as inline \c if statements). */ #define MACROE while (0) - - /** Defines a volatile NOP statement which cannot be optimized out by the compiler, and thus can always - * be set as a breakpoint in the resulting code. Useful for debugging purposes, where the optimizer + + /** Convenience macro to determine the larger of two values. + * + * \note This macro should only be used with operands that do not have side effects from being evaluated + * multiple times. + * + * \param[in] x First value to compare + * \param[in] y First value to compare + * + * \return The larger of the two input parameters + */ + #define MAX(x, y) ((x > y) ? x : y) + + /** Convenience macro to determine the smaller of two values. + * + * \note This macro should only be used with operands that do not have side effects from being evaluated + * multiple times. + * + * \param[in] x First value to compare + * \param[in] y First value to compare + * + * \return The smaller of the two input parameters + */ + #define MIN(x, y) ((x < y) ? x : y) + + /** Defines a volatile \c NOP statement which cannot be optimized out by the compiler, and thus can always + * be set as a breakpoint in the resulting code. Useful for debugging purposes, where the optimiser * removes/reorders code to the point where break points cannot reliably be set. * * \ingroup Group_Debugging */ - #define JTAG_DEBUG_POINT() asm volatile ("NOP" ::) + #define JTAG_DEBUG_POINT() __asm__ __volatile__ ("NOP" ::) - /** Defines an explicit JTAG break point in the resulting binary via the ASM BREAK statement. When + /** Defines an explicit JTAG break point in the resulting binary via the assembly \c BREAK statement. When * a JTAG is used, this causes the program execution to halt when reached until manually resumed. * * \ingroup Group_Debugging */ - #define JTAG_DEBUG_BREAK() asm volatile ("BREAK" ::) - - /** Macro for testing condition "x" and breaking via JTAG_DEBUG_BREAK() if the condition is false. + #define JTAG_DEBUG_BREAK() __asm__ __volatile__ ("BREAK" ::) + + /** Macro for testing condition "x" and breaking via \ref JTAG_DEBUG_BREAK() if the condition is false. + * + * \param[in] Condition Condition that will be evaluated, * * \ingroup Group_Debugging */ - #define JTAG_DEBUG_ASSERT(x) MACROS{ if (!(x)) { JTAG_DEBUG_BREAK(); } }MACROE + #define JTAG_DEBUG_ASSERT(Condition) MACROS{ if (!(Condition)) { JTAG_DEBUG_BREAK(); } }MACROE - /** Macro for testing condition "x" and writing debug data to the stdout stream if false. The stdout stream + /** Macro for testing condition "x" and writing debug data to the stdout stream if \c false. The stdout stream * must be pre-initialized before this macro is run and linked to an output device, such as the AVR's USART * peripheral. * - * The output takes the form "{FILENAME}: Function {FUNCTION NAME}, Line {LINE NUMBER}: Assertion {x} failed." + * The output takes the form "{FILENAME}: Function {FUNCTION NAME}, Line {LINE NUMBER}: Assertion {Condition} failed." + * + * \param[in] Condition Condition that will be evaluated, * * \ingroup Group_Debugging */ - #define STDOUT_ASSERT(x) MACROS{ if (!(x)) { printf_P(PSTR("%s: Function \"%s\", Line %d: " \ - "Assertion \"%s\" failed.\r\n"), \ - __FILE__, __func__, __LINE__, #x); } }MACROE + #define STDOUT_ASSERT(Condition) MACROS{ if (!(x)) { printf_P(PSTR("%s: Function \"%s\", Line %d: " \ + "Assertion \"%s\" failed.\r\n"), \ + __FILE__, __func__, __LINE__, #Condition); } }MACROE + + /** Forces GCC to use pointer indirection (via the AVR's pointer register pairs) when accessing the given + * struct pointer. In some cases GCC will emit non-optimal assembly code when accessing a structure through + * a pointer, resulting in a larger binary. When this macro is used on a (non \c const) structure pointer before + * use, it will force GCC to use pointer indirection on the elements rather than direct store and load + * instructions. + * + * \param[in, out] StructPtr Pointer to a structure which is to be forced into indirect access mode. + */ + #define GCC_FORCE_POINTER_ACCESS(StructPtr) __asm__ __volatile__("" : "=b" (StructPtr) : "0" (StructPtr)) #if !defined(pgm_read_ptr) || defined(__DOXYGEN__) - /** Reads a pointer out of PROGMEM space. This is currently a wrapper for the avr-libc pgm_read_ptr() - * macro with a void* cast, so that its value can be assigned diretly to a pointer variable or used + /** Reads a pointer out of PROGMEM space. This is currently a wrapper for the avr-libc \c pgm_read_ptr() + * macro with a \c void* cast, so that its value can be assigned directly to a pointer variable or used * in pointer arithmetic without further casting in C. In a future avr-libc distribution this will be * part of the standard API and will be implemented in a more formal manner. * @@ -164,15 +203,15 @@ return Byte; } - + /** Function to reverse the byte ordering of the individual bytes in a 16 bit number. * * \ingroup Group_BitManip * * \param[in] Word Word of data whose bytes are to be swapped. */ - static inline uint16_t SwapEndian_16(uint16_t Word) ATTR_WARN_UNUSED_RESULT ATTR_CONST; - static inline uint16_t SwapEndian_16(uint16_t Word) + static inline uint16_t SwapEndian_16(const uint16_t Word) ATTR_WARN_UNUSED_RESULT ATTR_CONST; + static inline uint16_t SwapEndian_16(const uint16_t Word) { uint8_t Temp; @@ -181,13 +220,13 @@ uint16_t Word; uint8_t Bytes[2]; } Data; - + Data.Word = Word; - + Temp = Data.Bytes[0]; Data.Bytes[0] = Data.Bytes[1]; Data.Bytes[1] = Temp; - + return Data.Word; } @@ -197,8 +236,8 @@ * * \param[in] DWord Double word of data whose bytes are to be swapped. */ - static inline uint32_t SwapEndian_32(uint32_t DWord) ATTR_WARN_UNUSED_RESULT ATTR_CONST; - static inline uint32_t SwapEndian_32(uint32_t DWord) + static inline uint32_t SwapEndian_32(const uint32_t DWord) ATTR_WARN_UNUSED_RESULT ATTR_CONST; + static inline uint32_t SwapEndian_32(const uint32_t DWord) { uint8_t Temp; @@ -207,17 +246,17 @@ uint32_t DWord; uint8_t Bytes[4]; } Data; - + Data.DWord = DWord; - + Temp = Data.Bytes[0]; Data.Bytes[0] = Data.Bytes[3]; Data.Bytes[3] = Temp; - + Temp = Data.Bytes[1]; Data.Bytes[1] = Data.Bytes[2]; Data.Bytes[2] = Temp; - + return Data.DWord; } @@ -228,11 +267,13 @@ * \param[in,out] Data Pointer to a number containing an even number of bytes to be reversed. * \param[in] Bytes Length of the data in bytes. */ - static inline void SwapEndian_n(void* Data, uint8_t Bytes); - static inline void SwapEndian_n(void* Data, uint8_t Bytes) + static inline void SwapEndian_n(void* Data, + uint8_t Bytes) ATTR_NON_NULL_PTR_ARG(1); + static inline void SwapEndian_n(void* Data, + uint8_t Bytes) { uint8_t* CurrDataPos = (uint8_t*)Data; - + while (Bytes > 1) { uint8_t Temp = *CurrDataPos; @@ -247,3 +288,4 @@ #endif /** @} */ +