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SEGGER_RTT.c
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SEGGER_RTT.c
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/*********************************************************************
* SEGGER Microcontroller GmbH *
* The Embedded Experts *
**********************************************************************
* *
* (c) 2014 - 2019 SEGGER Microcontroller GmbH *
* *
* www.segger.com Support: support@segger.com *
* *
**********************************************************************
* *
* All rights reserved. *
* *
* Redistribution and use in source and binary forms, with or *
* without modification, are permitted provided that the following *
* conditions are met: *
* *
* - Redistributions of source code must retain the above copyright *
* notice, this list of conditions and the following disclaimer. *
* *
* - Neither the name of SEGGER Microcontroller GmbH *
* nor the names of its contributors may be used to endorse or *
* promote products derived from this software without specific *
* prior written permission. *
* *
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND *
* CONTRIBUTORS "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 SEGGER Microcontroller GmbH 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. *
* *
**********************************************************************
---------------------------END-OF-HEADER------------------------------
File : SEGGER_RTT.c
Purpose : Implementation of SEGGER real-time transfer (RTT) which
allows real-time communication on targets which support
debugger memory accesses while the CPU is running.
Revision: $Rev: 12804 $
Additional information:
Type "int" is assumed to be 32-bits in size
H->T Host to target communication
T->H Target to host communication
RTT channel 0 is always present and reserved for Terminal usage.
Name is fixed to "Terminal"
Effective buffer size: SizeOfBuffer - 1
WrOff == RdOff: Buffer is empty
WrOff == (RdOff - 1): Buffer is full
WrOff > RdOff: Free space includes wrap-around
WrOff < RdOff: Used space includes wrap-around
(WrOff == (SizeOfBuffer - 1)) && (RdOff == 0):
Buffer full and wrap-around after next byte
----------------------------------------------------------------------
*/
#include "SEGGER_RTT.h"
#include <string.h> // for memcpy
/*********************************************************************
*
* Configuration, default values
*
**********************************************************************
*/
#ifndef BUFFER_SIZE_UP
#define BUFFER_SIZE_UP 1024 // Size of the buffer for terminal output of target, up to host
#endif
#ifndef BUFFER_SIZE_DOWN
#define BUFFER_SIZE_DOWN 16 // Size of the buffer for terminal input to target from host (Usually keyboard input)
#endif
#ifndef SEGGER_RTT_MAX_NUM_UP_BUFFERS
#define SEGGER_RTT_MAX_NUM_UP_BUFFERS 2 // Number of up-buffers (T->H) available on this target
#endif
#ifndef SEGGER_RTT_MAX_NUM_DOWN_BUFFERS
#define SEGGER_RTT_MAX_NUM_DOWN_BUFFERS 2 // Number of down-buffers (H->T) available on this target
#endif
#ifndef SEGGER_RTT_BUFFER_SECTION
#if defined(SEGGER_RTT_SECTION)
#define SEGGER_RTT_BUFFER_SECTION SEGGER_RTT_SECTION
#endif
#endif
#ifndef SEGGER_RTT_ALIGNMENT
#define SEGGER_RTT_ALIGNMENT 0
#endif
#ifndef SEGGER_RTT_BUFFER_ALIGNMENT
#define SEGGER_RTT_BUFFER_ALIGNMENT 0
#endif
#ifndef SEGGER_RTT_MODE_DEFAULT
#define SEGGER_RTT_MODE_DEFAULT SEGGER_RTT_MODE_NO_BLOCK_SKIP
#endif
#ifndef SEGGER_RTT_LOCK
#define SEGGER_RTT_LOCK()
#endif
#ifndef SEGGER_RTT_UNLOCK
#define SEGGER_RTT_UNLOCK()
#endif
#ifndef STRLEN
#define STRLEN(a) strlen((a))
#endif
#ifndef SEGGER_RTT_MEMCPY_USE_BYTELOOP
#define SEGGER_RTT_MEMCPY_USE_BYTELOOP 0
#endif
#ifndef SEGGER_RTT_MEMCPY
#ifdef MEMCPY
#define SEGGER_RTT_MEMCPY(pDest, pSrc, NumBytes) MEMCPY((pDest), (pSrc), (NumBytes))
#else
#define SEGGER_RTT_MEMCPY(pDest, pSrc, NumBytes) memcpy((pDest), (pSrc), (NumBytes))
#endif
#endif
#ifndef MIN
#define MIN(a, b) (((a) < (b)) ? (a) : (b))
#endif
#ifndef MAX
#define MAX(a, b) (((a) > (b)) ? (a) : (b))
#endif
//
// For some environments, NULL may not be defined until certain headers are included
//
#ifndef NULL
#define NULL 0
#endif
/*********************************************************************
*
* Defines, fixed
*
**********************************************************************
*/
#if (defined __ICCARM__) || (defined __ICCRX__)
#define RTT_PRAGMA(P) _Pragma(#P)
#endif
#if SEGGER_RTT_ALIGNMENT || SEGGER_RTT_BUFFER_ALIGNMENT
#if (defined __GNUC__)
#define SEGGER_RTT_ALIGN(Var, Alignment) Var __attribute__ ((aligned (Alignment)))
#elif (defined __ICCARM__) || (defined __ICCRX__)
#define PRAGMA(A) _Pragma(#A)
#define SEGGER_RTT_ALIGN(Var, Alignment) RTT_PRAGMA(data_alignment=Alignment) \
Var
#elif (defined __CC_ARM)
#define SEGGER_RTT_ALIGN(Var, Alignment) Var __attribute__ ((aligned (Alignment)))
#else
#error "Alignment not supported for this compiler."
#endif
#else
#define SEGGER_RTT_ALIGN(Var, Alignment) Var
#endif
#if defined(SEGGER_RTT_SECTION) || defined (SEGGER_RTT_BUFFER_SECTION)
#if (defined __GNUC__)
#define SEGGER_RTT_PUT_SECTION(Var, Section) __attribute__ ((section (Section))) Var
#elif (defined __ICCARM__) || (defined __ICCRX__)
#define SEGGER_RTT_PUT_SECTION(Var, Section) RTT_PRAGMA(location=Section) \
Var
#elif (defined __CC_ARM)
#define SEGGER_RTT_PUT_SECTION(Var, Section) __attribute__ ((section (Section), zero_init)) Var
#else
#error "Section placement not supported for this compiler."
#endif
#else
#define SEGGER_RTT_PUT_SECTION(Var, Section) Var
#endif
#if SEGGER_RTT_ALIGNMENT
#define SEGGER_RTT_CB_ALIGN(Var) SEGGER_RTT_ALIGN(Var, SEGGER_RTT_ALIGNMENT)
#else
#define SEGGER_RTT_CB_ALIGN(Var) Var
#endif
#if SEGGER_RTT_BUFFER_ALIGNMENT
#define SEGGER_RTT_BUFFER_ALIGN(Var) SEGGER_RTT_ALIGN(Var, SEGGER_RTT_BUFFER_ALIGNMENT)
#else
#define SEGGER_RTT_BUFFER_ALIGN(Var) Var
#endif
#if defined(SEGGER_RTT_SECTION)
#define SEGGER_RTT_PUT_CB_SECTION(Var) SEGGER_RTT_PUT_SECTION(Var, SEGGER_RTT_SECTION)
#else
#define SEGGER_RTT_PUT_CB_SECTION(Var) Var
#endif
#if defined(SEGGER_RTT_BUFFER_SECTION)
#define SEGGER_RTT_PUT_BUFFER_SECTION(Var) SEGGER_RTT_PUT_SECTION(Var, SEGGER_RTT_BUFFER_SECTION)
#else
#define SEGGER_RTT_PUT_BUFFER_SECTION(Var) Var
#endif
/*********************************************************************
*
* Static const data
*
**********************************************************************
*/
static unsigned char _aTerminalId[16] = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
/*********************************************************************
*
* Static data
*
**********************************************************************
*/
//
// RTT Control Block and allocate buffers for channel 0
//
SEGGER_RTT_PUT_CB_SECTION(SEGGER_RTT_CB_ALIGN(SEGGER_RTT_CB _SEGGER_RTT));
SEGGER_RTT_PUT_BUFFER_SECTION(SEGGER_RTT_BUFFER_ALIGN(static char _acUpBuffer [BUFFER_SIZE_UP]));
SEGGER_RTT_PUT_BUFFER_SECTION(SEGGER_RTT_BUFFER_ALIGN(static char _acDownBuffer[BUFFER_SIZE_DOWN]));
static char _ActiveTerminal;
/*********************************************************************
*
* Static functions
*
**********************************************************************
*/
/*********************************************************************
*
* _DoInit()
*
* Function description
* Initializes the control block an buffers.
* May only be called via INIT() to avoid overriding settings.
*
*/
#define INIT() do { \
if (_SEGGER_RTT.acID[0] == '\0') { _DoInit(); } \
} while (0)
static void _DoInit(void) {
SEGGER_RTT_CB* p;
//
// Initialize control block
//
p = &_SEGGER_RTT;
p->MaxNumUpBuffers = SEGGER_RTT_MAX_NUM_UP_BUFFERS;
p->MaxNumDownBuffers = SEGGER_RTT_MAX_NUM_DOWN_BUFFERS;
//
// Initialize up buffer 0
//
p->aUp[0].sName = "Terminal";
p->aUp[0].pBuffer = _acUpBuffer;
p->aUp[0].SizeOfBuffer = sizeof(_acUpBuffer);
p->aUp[0].RdOff = 0u;
p->aUp[0].WrOff = 0u;
p->aUp[0].Flags = SEGGER_RTT_MODE_DEFAULT;
//
// Initialize down buffer 0
//
p->aDown[0].sName = "Terminal";
p->aDown[0].pBuffer = _acDownBuffer;
p->aDown[0].SizeOfBuffer = sizeof(_acDownBuffer);
p->aDown[0].RdOff = 0u;
p->aDown[0].WrOff = 0u;
p->aDown[0].Flags = SEGGER_RTT_MODE_DEFAULT;
//
// Finish initialization of the control block.
// Copy Id string in three steps to make sure "SEGGER RTT" is not found
// in initializer memory (usually flash) by J-Link
//
strcpy(&p->acID[7], "RTT");
strcpy(&p->acID[0], "SEGGER");
p->acID[6] = ' ';
}
/*********************************************************************
*
* _WriteBlocking()
*
* Function description
* Stores a specified number of characters in SEGGER RTT ring buffer
* and updates the associated write pointer which is periodically
* read by the host.
* The caller is responsible for managing the write chunk sizes as
* _WriteBlocking() will block until all data has been posted successfully.
*
* Parameters
* pRing Ring buffer to post to.
* pBuffer Pointer to character array. Does not need to point to a \0 terminated string.
* NumBytes Number of bytes to be stored in the SEGGER RTT control block.
*
* Return value
* >= 0 - Number of bytes written into buffer.
*/
static unsigned _WriteBlocking(SEGGER_RTT_BUFFER_UP* pRing, const char* pBuffer, unsigned NumBytes) {
unsigned NumBytesToWrite;
unsigned NumBytesWritten;
unsigned RdOff;
unsigned WrOff;
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
char* pDst;
#endif
//
// Write data to buffer and handle wrap-around if necessary
//
NumBytesWritten = 0u;
WrOff = pRing->WrOff;
do {
RdOff = pRing->RdOff; // May be changed by host (debug probe) in the meantime
if (RdOff > WrOff) {
NumBytesToWrite = RdOff - WrOff - 1u;
} else {
NumBytesToWrite = pRing->SizeOfBuffer - (WrOff - RdOff + 1u);
}
NumBytesToWrite = MIN(NumBytesToWrite, (pRing->SizeOfBuffer - WrOff)); // Number of bytes that can be written until buffer wrap-around
NumBytesToWrite = MIN(NumBytesToWrite, NumBytes);
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + WrOff;
NumBytesWritten += NumBytesToWrite;
NumBytes -= NumBytesToWrite;
WrOff += NumBytesToWrite;
while (NumBytesToWrite--) {
*pDst++ = *pBuffer++;
};
#else
SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pBuffer, NumBytesToWrite);
NumBytesWritten += NumBytesToWrite;
pBuffer += NumBytesToWrite;
NumBytes -= NumBytesToWrite;
WrOff += NumBytesToWrite;
#endif
if (WrOff == pRing->SizeOfBuffer) {
WrOff = 0u;
}
pRing->WrOff = WrOff;
} while (NumBytes);
//
return NumBytesWritten;
}
/*********************************************************************
*
* _WriteNoCheck()
*
* Function description
* Stores a specified number of characters in SEGGER RTT ring buffer
* and updates the associated write pointer which is periodically
* read by the host.
* It is callers responsibility to make sure data actually fits in buffer.
*
* Parameters
* pRing Ring buffer to post to.
* pBuffer Pointer to character array. Does not need to point to a \0 terminated string.
* NumBytes Number of bytes to be stored in the SEGGER RTT control block.
*
* Notes
* (1) If there might not be enough space in the "Up"-buffer, call _WriteBlocking
*/
static void _WriteNoCheck(SEGGER_RTT_BUFFER_UP* pRing, const char* pData, unsigned NumBytes) {
unsigned NumBytesAtOnce;
unsigned WrOff;
unsigned Rem;
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
char* pDst;
#endif
WrOff = pRing->WrOff;
Rem = pRing->SizeOfBuffer - WrOff;
if (Rem > NumBytes) {
//
// All data fits before wrap around
//
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + WrOff;
WrOff += NumBytes;
while (NumBytes--) {
*pDst++ = *pData++;
};
pRing->WrOff = WrOff;
#else
SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, NumBytes);
pRing->WrOff = WrOff + NumBytes;
#endif
} else {
//
// We reach the end of the buffer, so need to wrap around
//
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + WrOff;
NumBytesAtOnce = Rem;
while (NumBytesAtOnce--) {
*pDst++ = *pData++;
};
pDst = pRing->pBuffer;
NumBytesAtOnce = NumBytes - Rem;
while (NumBytesAtOnce--) {
*pDst++ = *pData++;
};
pRing->WrOff = NumBytes - Rem;
#else
NumBytesAtOnce = Rem;
SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, NumBytesAtOnce);
NumBytesAtOnce = NumBytes - Rem;
SEGGER_RTT_MEMCPY(pRing->pBuffer, pData + Rem, NumBytesAtOnce);
pRing->WrOff = NumBytesAtOnce;
#endif
}
}
/*********************************************************************
*
* _PostTerminalSwitch()
*
* Function description
* Switch terminal to the given terminal ID. It is the caller's
* responsibility to ensure the terminal ID is correct and there is
* enough space in the buffer for this to complete successfully.
*
* Parameters
* pRing Ring buffer to post to.
* TerminalId Terminal ID to switch to.
*/
static void _PostTerminalSwitch(SEGGER_RTT_BUFFER_UP* pRing, unsigned char TerminalId) {
unsigned char ac[2];
ac[0] = 0xFFu;
ac[1] = _aTerminalId[TerminalId]; // Caller made already sure that TerminalId does not exceed our terminal limit
_WriteBlocking(pRing, (const char*)ac, 2u);
}
/*********************************************************************
*
* _GetAvailWriteSpace()
*
* Function description
* Returns the number of bytes that can be written to the ring
* buffer without blocking.
*
* Parameters
* pRing Ring buffer to check.
*
* Return value
* Number of bytes that are free in the buffer.
*/
static unsigned _GetAvailWriteSpace(SEGGER_RTT_BUFFER_UP* pRing) {
unsigned RdOff;
unsigned WrOff;
unsigned r;
//
// Avoid warnings regarding volatile access order. It's not a problem
// in this case, but dampen compiler enthusiasm.
//
RdOff = pRing->RdOff;
WrOff = pRing->WrOff;
if (RdOff <= WrOff) {
r = pRing->SizeOfBuffer - 1u - WrOff + RdOff;
} else {
r = RdOff - WrOff - 1u;
}
return r;
}
/*********************************************************************
*
* Public code
*
**********************************************************************
*/
/*********************************************************************
*
* SEGGER_RTT_ReadNoLock()
*
* Function description
* Reads characters from SEGGER real-time-terminal control block
* which have been previously stored by the host.
* Do not lock against interrupts and multiple access.
*
* Parameters
* BufferIndex Index of Down-buffer to be used (e.g. 0 for "Terminal").
* pBuffer Pointer to buffer provided by target application, to copy characters from RTT-down-buffer to.
* BufferSize Size of the target application buffer.
*
* Return value
* Number of bytes that have been read.
*/
unsigned SEGGER_RTT_ReadNoLock(unsigned BufferIndex, void* pData, unsigned BufferSize) {
unsigned NumBytesRem;
unsigned NumBytesRead;
unsigned RdOff;
unsigned WrOff;
unsigned char* pBuffer;
SEGGER_RTT_BUFFER_DOWN* pRing;
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
const char* pSrc;
#endif
//
INIT();
pRing = &_SEGGER_RTT.aDown[BufferIndex];
pBuffer = (unsigned char*)pData;
RdOff = pRing->RdOff;
WrOff = pRing->WrOff;
NumBytesRead = 0u;
//
// Read from current read position to wrap-around of buffer, first
//
if (RdOff > WrOff) {
NumBytesRem = pRing->SizeOfBuffer - RdOff;
NumBytesRem = MIN(NumBytesRem, BufferSize);
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pSrc = pRing->pBuffer + RdOff;
NumBytesRead += NumBytesRem;
BufferSize -= NumBytesRem;
RdOff += NumBytesRem;
while (NumBytesRem--) {
*pBuffer++ = *pSrc++;
};
#else
SEGGER_RTT_MEMCPY(pBuffer, pRing->pBuffer + RdOff, NumBytesRem);
NumBytesRead += NumBytesRem;
pBuffer += NumBytesRem;
BufferSize -= NumBytesRem;
RdOff += NumBytesRem;
#endif
//
// Handle wrap-around of buffer
//
if (RdOff == pRing->SizeOfBuffer) {
RdOff = 0u;
}
}
//
// Read remaining items of buffer
//
NumBytesRem = WrOff - RdOff;
NumBytesRem = MIN(NumBytesRem, BufferSize);
if (NumBytesRem > 0u) {
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pSrc = pRing->pBuffer + RdOff;
NumBytesRead += NumBytesRem;
BufferSize -= NumBytesRem;
RdOff += NumBytesRem;
while (NumBytesRem--) {
*pBuffer++ = *pSrc++;
};
#else
SEGGER_RTT_MEMCPY(pBuffer, pRing->pBuffer + RdOff, NumBytesRem);
NumBytesRead += NumBytesRem;
pBuffer += NumBytesRem;
BufferSize -= NumBytesRem;
RdOff += NumBytesRem;
#endif
}
if (NumBytesRead) {
pRing->RdOff = RdOff;
}
//
return NumBytesRead;
}
/*********************************************************************
*
* SEGGER_RTT_Read
*
* Function description
* Reads characters from SEGGER real-time-terminal control block
* which have been previously stored by the host.
*
* Parameters
* BufferIndex Index of Down-buffer to be used (e.g. 0 for "Terminal").
* pBuffer Pointer to buffer provided by target application, to copy characters from RTT-down-buffer to.
* BufferSize Size of the target application buffer.
*
* Return value
* Number of bytes that have been read.
*/
unsigned SEGGER_RTT_Read(unsigned BufferIndex, void* pBuffer, unsigned BufferSize) {
unsigned NumBytesRead;
//
SEGGER_RTT_LOCK();
//
// Call the non-locking read function
//
NumBytesRead = SEGGER_RTT_ReadNoLock(BufferIndex, pBuffer, BufferSize);
//
// Finish up.
//
SEGGER_RTT_UNLOCK();
//
return NumBytesRead;
}
/*********************************************************************
*
* SEGGER_RTT_WriteWithOverwriteNoLock
*
* Function description
* Stores a specified number of characters in SEGGER RTT
* control block.
* SEGGER_RTT_WriteWithOverwriteNoLock does not lock the application
* and overwrites data if the data does not fit into the buffer.
*
* Parameters
* BufferIndex Index of "Up"-buffer to be used (e.g. 0 for "Terminal").
* pBuffer Pointer to character array. Does not need to point to a \0 terminated string.
* NumBytes Number of bytes to be stored in the SEGGER RTT control block.
*
* Notes
* (1) If there is not enough space in the "Up"-buffer, data is overwritten.
* (2) For performance reasons this function does not call Init()
* and may only be called after RTT has been initialized.
* Either by calling SEGGER_RTT_Init() or calling another RTT API function first.
* (3) Do not use SEGGER_RTT_WriteWithOverwriteNoLock if a J-Link
* connection reads RTT data.
*/
void SEGGER_RTT_WriteWithOverwriteNoLock(unsigned BufferIndex, const void* pBuffer, unsigned NumBytes) {
const char* pData;
SEGGER_RTT_BUFFER_UP* pRing;
unsigned Avail;
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
char* pDst;
#endif
pData = (const char *)pBuffer;
//
// Get "to-host" ring buffer and copy some elements into local variables.
//
pRing = &_SEGGER_RTT.aUp[BufferIndex];
//
// Check if we will overwrite data and need to adjust the RdOff.
//
if (pRing->WrOff == pRing->RdOff) {
Avail = pRing->SizeOfBuffer - 1u;
} else if ( pRing->WrOff < pRing->RdOff) {
Avail = pRing->RdOff - pRing->WrOff - 1u;
} else {
Avail = pRing->RdOff - pRing->WrOff - 1u + pRing->SizeOfBuffer;
}
if (NumBytes > Avail) {
pRing->RdOff += (NumBytes - Avail);
while (pRing->RdOff >= pRing->SizeOfBuffer) {
pRing->RdOff -= pRing->SizeOfBuffer;
}
}
//
// Write all data, no need to check the RdOff, but possibly handle multiple wrap-arounds
//
Avail = pRing->SizeOfBuffer - pRing->WrOff;
do {
if (Avail > NumBytes) {
//
// Last round
//
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + pRing->WrOff;
Avail = NumBytes;
while (NumBytes--) {
*pDst++ = *pData++;
};
pRing->WrOff += Avail;
#else
SEGGER_RTT_MEMCPY(pRing->pBuffer + pRing->WrOff, pData, NumBytes);
pRing->WrOff += NumBytes;
#endif
break;
} else {
//
// Wrap-around necessary, write until wrap-around and reset WrOff
//
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + pRing->WrOff;
NumBytes -= Avail;
while (Avail--) {
*pDst++ = *pData++;
};
pRing->WrOff = 0;
#else
SEGGER_RTT_MEMCPY(pRing->pBuffer + pRing->WrOff, pData, Avail);
pData += Avail;
pRing->WrOff = 0;
NumBytes -= Avail;
#endif
Avail = (pRing->SizeOfBuffer - 1);
}
} while (NumBytes);
}
/*********************************************************************
*
* SEGGER_RTT_WriteSkipNoLock
*
* Function description
* Stores a specified number of characters in SEGGER RTT
* control block which is then read by the host.
* SEGGER_RTT_WriteSkipNoLock does not lock the application and
* skips all data, if the data does not fit into the buffer.
*
* Parameters
* BufferIndex Index of "Up"-buffer to be used (e.g. 0 for "Terminal").
* pBuffer Pointer to character array. Does not need to point to a \0 terminated string.
* NumBytes Number of bytes to be stored in the SEGGER RTT control block.
*
* Return value
* Number of bytes which have been stored in the "Up"-buffer.
*
* Notes
* (1) If there is not enough space in the "Up"-buffer, all data is dropped.
* (2) For performance reasons this function does not call Init()
* and may only be called after RTT has been initialized.
* Either by calling SEGGER_RTT_Init() or calling another RTT API function first.
*/
unsigned SEGGER_RTT_WriteSkipNoLock(unsigned BufferIndex, const void* pBuffer, unsigned NumBytes) {
const char* pData;
SEGGER_RTT_BUFFER_UP* pRing;
unsigned Avail;
unsigned RdOff;
unsigned WrOff;
unsigned Rem;
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
char* pDst;
#endif
pData = (const char *)pBuffer;
//
// Get "to-host" ring buffer and copy some elements into local variables.
//
pRing = &_SEGGER_RTT.aUp[BufferIndex];
RdOff = pRing->RdOff;
WrOff = pRing->WrOff;
//
// Handle the most common cases fastest.
// Which is:
// RdOff <= WrOff -> Space until wrap around is free.
// AND
// WrOff + NumBytes < SizeOfBuffer -> No Wrap around necessary.
//
// OR
//
// RdOff > WrOff -> Space until RdOff - 1 is free.
// AND
// WrOff + NumBytes < RdOff -> Data fits into buffer
//
if (RdOff <= WrOff) {
//
// Get space until WrOff will be at wrap around.
//
Avail = pRing->SizeOfBuffer - 1u - WrOff ;
if (Avail >= NumBytes) {
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + WrOff;
WrOff += NumBytes;
while (NumBytes--) {
*pDst++ = *pData++;
};
pRing->WrOff = WrOff;
#else
SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, NumBytes);
pRing->WrOff = WrOff + NumBytes;
#endif
return 1;
}
//
// If data did not fit into space until wrap around calculate complete space in buffer.
//
Avail += RdOff;
//
// If there is still no space for the whole of this output, don't bother.
//
if (Avail >= NumBytes) {
//
// OK, we have enough space in buffer. Copy in one or 2 chunks
//
Rem = pRing->SizeOfBuffer - WrOff; // Space until end of buffer
if (Rem > NumBytes) {
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + WrOff;
WrOff += NumBytes;
while (NumBytes--) {
*pDst++ = *pData++;
};
pRing->WrOff = WrOff;
#else
SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, NumBytes);
pRing->WrOff = WrOff + NumBytes;
#endif
} else {
//
// We reach the end of the buffer, so need to wrap around
//
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + WrOff;
NumBytes -= Rem;
WrOff = NumBytes;
do {
*pDst++ = *pData++;
} while (--Rem);
pDst = pRing->pBuffer;
while (NumBytes--) {
*pDst++ = *pData++;
};
pRing->WrOff = WrOff;
#else
SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, Rem);
SEGGER_RTT_MEMCPY(pRing->pBuffer, pData + Rem, NumBytes - Rem);
pRing->WrOff = NumBytes - Rem;
#endif
}
return 1;
}
} else {
Avail = RdOff - WrOff - 1u;
if (Avail >= NumBytes) {
#if SEGGER_RTT_MEMCPY_USE_BYTELOOP
pDst = pRing->pBuffer + WrOff;
WrOff += NumBytes;
while (NumBytes--) {
*pDst++ = *pData++;
};
pRing->WrOff = WrOff;
#else
SEGGER_RTT_MEMCPY(pRing->pBuffer + WrOff, pData, NumBytes);
pRing->WrOff = WrOff + NumBytes;
#endif
return 1;
}
}
//
// If we reach this point no data has been written
//
return 0;
}
/*********************************************************************
*
* SEGGER_RTT_WriteNoLock
*
* Function description
* Stores a specified number of characters in SEGGER RTT
* control block which is then read by the host.
* SEGGER_RTT_WriteNoLock does not lock the application.
*
* Parameters
* BufferIndex Index of "Up"-buffer to be used (e.g. 0 for "Terminal").
* pBuffer Pointer to character array. Does not need to point to a \0 terminated string.
* NumBytes Number of bytes to be stored in the SEGGER RTT control block.
*
* Return value
* Number of bytes which have been stored in the "Up"-buffer.
*
* Notes
* (1) Data is stored according to buffer flags.
* (2) For performance reasons this function does not call Init()
* and may only be called after RTT has been initialized.
* Either by calling SEGGER_RTT_Init() or calling another RTT API function first.
*/
unsigned SEGGER_RTT_WriteNoLock(unsigned BufferIndex, const void* pBuffer, unsigned NumBytes) {
unsigned Status;
unsigned Avail;
const char* pData;
SEGGER_RTT_BUFFER_UP* pRing;
pData = (const char *)pBuffer;
//
// Get "to-host" ring buffer.
//
pRing = &_SEGGER_RTT.aUp[BufferIndex];
//
// How we output depends upon the mode...
//
switch (pRing->Flags) {
case SEGGER_RTT_MODE_NO_BLOCK_SKIP:
//
// If we are in skip mode and there is no space for the whole
// of this output, don't bother.
//
Avail = _GetAvailWriteSpace(pRing);
if (Avail < NumBytes) {
Status = 0u;
} else {
Status = NumBytes;
_WriteNoCheck(pRing, pData, NumBytes);
}
break;
case SEGGER_RTT_MODE_NO_BLOCK_TRIM:
//
// If we are in trim mode, trim to what we can output without blocking.
//
Avail = _GetAvailWriteSpace(pRing);
Status = Avail < NumBytes ? Avail : NumBytes;
_WriteNoCheck(pRing, pData, Status);
break;
case SEGGER_RTT_MODE_BLOCK_IF_FIFO_FULL:
//
// If we are in blocking mode, output everything.
//
Status = _WriteBlocking(pRing, pData, NumBytes);
break;
default:
Status = 0u;
break;
}
//
// Finish up.
//
return Status;
}
/*********************************************************************
*
* SEGGER_RTT_Write
*
* Function description
* Stores a specified number of characters in SEGGER RTT
* control block which is then read by the host.
*
* Parameters
* BufferIndex Index of "Up"-buffer to be used (e.g. 0 for "Terminal").
* pBuffer Pointer to character array. Does not need to point to a \0 terminated string.
* NumBytes Number of bytes to be stored in the SEGGER RTT control block.
*
* Return value
* Number of bytes which have been stored in the "Up"-buffer.
*
* Notes
* (1) Data is stored according to buffer flags.
*/
unsigned SEGGER_RTT_Write(unsigned BufferIndex, const void* pBuffer, unsigned NumBytes) {
unsigned Status;
//
INIT();
SEGGER_RTT_LOCK();
//
// Call the non-locking write function
//
Status = SEGGER_RTT_WriteNoLock(BufferIndex, pBuffer, NumBytes);
//
// Finish up.
//
SEGGER_RTT_UNLOCK();
//
return Status;
}
/*********************************************************************
*
* SEGGER_RTT_WriteString
*
* Function description
* Stores string in SEGGER RTT control block.
* This data is read by the host.
*
* Parameters
* BufferIndex Index of "Up"-buffer to be used (e.g. 0 for "Terminal").
* s Pointer to string.
*
* Return value
* Number of bytes which have been stored in the "Up"-buffer.
*
* Notes
* (1) Data is stored according to buffer flags.
* (2) String passed to this function has to be \0 terminated
* (3) \0 termination character is *not* stored in RTT buffer
*/
unsigned SEGGER_RTT_WriteString(unsigned BufferIndex, const char* s) {
unsigned Len;
Len = STRLEN(s);
return SEGGER_RTT_Write(BufferIndex, s, Len);
}
/*********************************************************************
*
* SEGGER_RTT_PutCharSkipNoLock
*
* Function description
* Stores a single character/byte in SEGGER RTT buffer.
* SEGGER_RTT_PutCharSkipNoLock does not lock the application and