blob: f68c105c47a6613a9faab2751bb0ad81e788051b [file] [log] [blame]
/*********************************************************************
* SEGGER MICROCONTROLLER GmbH & Co. KG *
* Solutions for real time microcontroller applications *
**********************************************************************
* *
* (c) 2014-2014 SEGGER Microcontroller GmbH & Co. KG *
* *
* Internet: www.segger.com Support: support@segger.com *
* *
**********************************************************************
----------------------------------------------------------------------
File : SEGGER_RTT_printf.c
Date : 17 Dec 2014
Purpose : Replacement for printf to write formatted data via RTT
---------------------------END-OF-HEADER------------------------------
*/
#include "SEGGER_RTT.h"
#include "SEGGER_RTT_Conf.h"
/*********************************************************************
*
* Defines, configurable
*
**********************************************************************
*/
#ifndef SEGGER_RTT_PRINTF_BUFFER_SIZE
#define SEGGER_RTT_PRINTF_BUFFER_SIZE (64)
#endif
#include <stdlib.h>
#include <stdarg.h>
#define FORMAT_FLAG_LEFT_JUSTIFY (1 << 0)
#define FORMAT_FLAG_PAD_ZERO (1 << 1)
#define FORMAT_FLAG_PRINT_SIGN (1 << 2)
#define FORMAT_FLAG_ALTERNATE (1 << 3)
/*********************************************************************
*
* Types
*
**********************************************************************
*/
typedef struct {
char* pBuffer;
int BufferSize;
int Cnt;
int ReturnValue;
unsigned RTTBufferIndex;
} SEGGER_RTT_PRINTF_DESC;
/*********************************************************************
*
* Function prototypes
*
**********************************************************************
*/
int SEGGER_RTT_vprintf(unsigned BufferIndex, const char * sFormat, va_list * pParamList);
/*********************************************************************
*
* Static code
*
**********************************************************************
*/
/*********************************************************************
*
* _StoreChar
*/
static void _StoreChar(SEGGER_RTT_PRINTF_DESC * p, char c) {
int Cnt;
Cnt = p->Cnt;
if ((Cnt + 1) <= p->BufferSize) {
*(p->pBuffer + Cnt) = c;
p->Cnt = Cnt + 1;
p->ReturnValue++;
}
//
// Write part of string, when the buffer is full
//
if (p->Cnt == p->BufferSize) {
if (SEGGER_RTT_Write(p->RTTBufferIndex, p->pBuffer, p->Cnt) != p->Cnt) {
p->ReturnValue = -1;
} else {
p->Cnt = 0;
}
}
}
/*********************************************************************
*
* _PrintUnsigned
*/
static void _PrintUnsigned(SEGGER_RTT_PRINTF_DESC * pBufferDesc, unsigned v, unsigned Base, int NumDigits, unsigned FieldWidth, unsigned FormatFlags) {
static const char _aV2C[16] = {'0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };
unsigned Div;
unsigned Digit = 1;
unsigned Number;
unsigned Width;
char c;
Number = v;
//
// Get actual field width
//
Width = 1;
while (Number >= Base) {
Number = (Number / Base);
Width++;
}
if ((unsigned)NumDigits > Width) {
Width = NumDigits;
}
//
// Print leading chars if necessary
//
if ((FormatFlags & FORMAT_FLAG_LEFT_JUSTIFY) == 0) {
if (FieldWidth != 0) {
if (((FormatFlags & FORMAT_FLAG_PAD_ZERO) == FORMAT_FLAG_PAD_ZERO) && (NumDigits == 0)) {
c = '0';
} else {
c = ' ';
}
while ((FieldWidth != 0) && (Width < FieldWidth--)) {
_StoreChar(pBufferDesc, c);
if (pBufferDesc->ReturnValue < 0) {
return;
}
}
}
}
//
// Count how many digits are required by precision
//
while (((v / Digit) >= Base) | (NumDigits-- > 1)) {
Digit *= Base;
}
//
// Output digits
//
do {
Div = v / Digit;
v -= Div * Digit;
_StoreChar(pBufferDesc, _aV2C[Div]);
if (pBufferDesc->ReturnValue < 0) {
break;
}
Digit /= Base;
} while (Digit);
//
// Print trailing spaces if necessary
//
if ((FormatFlags & FORMAT_FLAG_LEFT_JUSTIFY) == FORMAT_FLAG_LEFT_JUSTIFY) {
if (FieldWidth != 0) {
while ((FieldWidth != 0) && (Width < FieldWidth--)) {
_StoreChar(pBufferDesc, ' ');
if (pBufferDesc->ReturnValue < 0) {
return;
}
}
}
}
}
/*********************************************************************
*
* _PrintInt
*/
static void _PrintInt(SEGGER_RTT_PRINTF_DESC * pBufferDesc, int v, unsigned Base, unsigned NumDigits, unsigned FieldWidth, unsigned FormatFlags) {
unsigned Width;
unsigned Number;
Number = (v < 0) ? -v : v;
//
// Get actual field width
//
Width = 1;
while (Number >= Base) {
Number = (Number / Base);
Width++;
}
if (NumDigits > Width) {
Width = NumDigits;
}
if ((FieldWidth > 0) && ((v < 0) || ((FormatFlags & FORMAT_FLAG_PRINT_SIGN) == FORMAT_FLAG_PRINT_SIGN))) {
FieldWidth--;
}
//
// Print leading spaces if necessary
//
if ((((FormatFlags & FORMAT_FLAG_PAD_ZERO) == 0) || (NumDigits != 0)) && ((FormatFlags & FORMAT_FLAG_LEFT_JUSTIFY) == 0)) {
if (FieldWidth != 0) {
while ((FieldWidth != 0) && (Width < FieldWidth--)) {
_StoreChar(pBufferDesc, ' ');
if (pBufferDesc->ReturnValue < 0) {
return;
}
}
}
}
//
// Print sign if necessary
//
if (v < 0) {
v = -v;
_StoreChar(pBufferDesc, '-');
if (pBufferDesc->ReturnValue < 0) {
return;
}
} else if ((FormatFlags & FORMAT_FLAG_PRINT_SIGN) == FORMAT_FLAG_PRINT_SIGN) {
_StoreChar(pBufferDesc, '+');
if (pBufferDesc->ReturnValue < 0) {
return;
}
}
//
// Print leading zeros if necessary
//
if (((FormatFlags & FORMAT_FLAG_PAD_ZERO) == FORMAT_FLAG_PAD_ZERO) && ((FormatFlags & FORMAT_FLAG_LEFT_JUSTIFY) == 0) && (NumDigits == 0)) {
if (FieldWidth != 0) {
while ((FieldWidth != 0) && (Width < FieldWidth--)) {
_StoreChar(pBufferDesc, '0');
if (pBufferDesc->ReturnValue < 0) {
return;
}
}
}
}
//
// Print number without sign
//
_PrintUnsigned(pBufferDesc, v, Base, NumDigits, FieldWidth, FormatFlags);
}
/*********************************************************************
*
* Public code
*
**********************************************************************
*/
/*********************************************************************
*
* SEGGER_RTT_vprintf
*
* Function description
* Stores a formatted 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")
* sFormat Pointer to format string
* pParamList Pointer to the list of arguments for the format string
*
* Return values
* >= 0: Number of bytes which have been stored in the "Up"-buffer.
* < 0: Error
*/
int SEGGER_RTT_vprintf(unsigned BufferIndex, const char * sFormat, va_list * pParamList) {
char c;
SEGGER_RTT_PRINTF_DESC BufferDesc;
int v;
unsigned NumDigits;
unsigned FormatFlags;
unsigned FieldWidth;
char acBuffer[SEGGER_RTT_PRINTF_BUFFER_SIZE];
BufferDesc.pBuffer = acBuffer;
BufferDesc.BufferSize = SEGGER_RTT_PRINTF_BUFFER_SIZE;
BufferDesc.Cnt = 0;
BufferDesc.RTTBufferIndex = BufferIndex;
BufferDesc.ReturnValue = 0;
do {
c = *sFormat++;
if (c == 0) {
break;
}
if (c == '%') {
//
// Filter out flags
//
FormatFlags = 0;
do {
c = *sFormat;
switch (c) {
case '-': FormatFlags |= FORMAT_FLAG_LEFT_JUSTIFY; sFormat++; break;
case '0': FormatFlags |= FORMAT_FLAG_PAD_ZERO; sFormat++; break;
case '+': FormatFlags |= FORMAT_FLAG_PRINT_SIGN; sFormat++; break;
case '#': FormatFlags |= FORMAT_FLAG_ALTERNATE; sFormat++; break;
default: goto FilterFieldWidth; break;
}
} while (1);
//
// filter out field with
//
FilterFieldWidth:
FieldWidth = 0;
do {
c = *sFormat;
if (c < '0' || c > '9') {
break;
}
sFormat++;
FieldWidth = FieldWidth * 10 + (c - '0');
} while (1);
//
// Filter out precision (number of digits to display)
//
NumDigits = 0;
c = *sFormat;
if (c == '.') {
sFormat++;
do {
c = *sFormat;
if (c < '0' || c > '9') {
break;
}
sFormat++;
NumDigits = NumDigits * 10 + (c - '0');
} while (1);
}
//
// Filter out length modifier
//
c = *sFormat;
do {
if (c == 'l' || c == 'h') {
c = *sFormat++;
continue;
}
break;
} while (1);
//
// Handle specifiers
//
switch (c) {
case 'c': {
char c0;
v = va_arg(*pParamList, int);
c0 = (char)v;
_StoreChar(&BufferDesc, c0);
break;
}
case 'd':
v = va_arg(*pParamList, int);
_PrintInt(&BufferDesc, v, 10, NumDigits, FieldWidth, FormatFlags);
break;
case 'u':
v = va_arg(*pParamList, int);
_PrintUnsigned(&BufferDesc, v, 10, NumDigits, FieldWidth, FormatFlags);
break;
case 'x':
case 'X':
v = va_arg(*pParamList, int);
_PrintUnsigned(&BufferDesc, v, 16, NumDigits, FieldWidth, FormatFlags);
break;
case 's':
{
const char * s = va_arg(*pParamList, const char *);
do {
c = *s++;
if (c == 0) {
break;
}
_StoreChar(&BufferDesc, c);
} while (BufferDesc.ReturnValue >= 0);
}
break;
case 'p':
v = va_arg(*pParamList, int);
_PrintUnsigned(&BufferDesc, v, 16, 8, 8, 0);
break;
case '%':
_StoreChar(&BufferDesc, '%');
break;
}
sFormat++;
} else {
_StoreChar(&BufferDesc, c);
}
} while (BufferDesc.ReturnValue >= 0);
if (BufferDesc.ReturnValue > 0) {
//
// Write remaining data, if any
//
if (BufferDesc.Cnt != 0) {
SEGGER_RTT_Write(BufferIndex, acBuffer, BufferDesc.Cnt);
}
BufferDesc.ReturnValue += BufferDesc.Cnt;
}
return BufferDesc.ReturnValue;
}
/*********************************************************************
*
* SEGGER_RTT_printf
*
* Function description
* Stores a formatted 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")
* sFormat Pointer to format string, followed by the arguments for conversion
*
* Return values
* >= 0: Number of bytes which have been stored in the "Up"-buffer.
* < 0: Error
*
* Notes
* (1) Conversion specifications have following syntax:
* %[flags][FieldWidth][.Precision]ConversionSpecifier
* (2) Supported flags:
* -: Left justify within the field width
* +: Always print sign extension for signed conversions
* 0: Pad with 0 instead of spaces. Ignored when using '-'-flag or precision
* Supported conversion specifiers:
* c: Print the argument as one char
* d: Print the argument as a signed integer
* u: Print the argument as an unsigned integer
* x: Print the argument as an hexadecimal integer
* s: Print the string pointed to by the argument
* p: Print the argument as an 8-digit hexadecimal integer. (Argument shall be a pointer to void.)
*/
int SEGGER_RTT_printf(unsigned BufferIndex, const char * sFormat, ...) {
va_list ParamList;
va_start(ParamList, sFormat);
return SEGGER_RTT_vprintf(BufferIndex, sFormat, &ParamList);
}
/*************************** End of file ****************************/