David Prentice / GLUE_STUFF_kbv

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Dependents:   TFT_Touch_botao_v1 TFT_Touch_exemplo5_git_touch TESTE_1 TFT_Touch_exemplo6_git_touch_button_3_

avr/dtostrf.c@2:81364824d56a, 2021-05-11 (annotated)

Committer:
davidprentice
Date:
Tue May 11 16:24:13 2021 +0000
Revision:
2:81364824d56a
Parent:
0:5952bbaff1c6 
add includes, typedef byte

Who changed what in which revision?

UserRevisionLine numberNew contents of line
davidprentice 0:5952bbaff1c6 1 /*
davidprentice 0:5952bbaff1c6 2 dtostrf - Emulation for dtostrf function from avr-libc
davidprentice 0:5952bbaff1c6 3 Copyright (c) 2013 Arduino. All rights reserved.
davidprentice 0:5952bbaff1c6 4 Written by Cristian Maglie <c.maglie@arduino.cc>
davidprentice 0:5952bbaff1c6 5
davidprentice 0:5952bbaff1c6 6 This library is free software; you can redistribute it and/or
davidprentice 0:5952bbaff1c6 7 modify it under the terms of the GNU Lesser General Public
davidprentice 0:5952bbaff1c6 8 License as published by the Free Software Foundation; either
davidprentice 0:5952bbaff1c6 9 version 2.1 of the License, or (at your option) any later version.
davidprentice 0:5952bbaff1c6 10
davidprentice 0:5952bbaff1c6 11 This library is distributed in the hope that it will be useful,
davidprentice 0:5952bbaff1c6 12 but WITHOUT ANY WARRANTY; without even the implied warranty of
davidprentice 0:5952bbaff1c6 13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
davidprentice 0:5952bbaff1c6 14 Lesser General Public License for more details.
davidprentice 0:5952bbaff1c6 15
davidprentice 0:5952bbaff1c6 16 You should have received a copy of the GNU Lesser General Public
davidprentice 0:5952bbaff1c6 17 License along with this library; if not, write to the Free Software
davidprentice 0:5952bbaff1c6 18 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
davidprentice 0:5952bbaff1c6 19 */
davidprentice 0:5952bbaff1c6 20
davidprentice 0:5952bbaff1c6 21 #include <stdio.h>
davidprentice 0:5952bbaff1c6 22 #include <stdlib.h>
davidprentice 0:5952bbaff1c6 23 #include <string.h>
davidprentice 0:5952bbaff1c6 24 #include <stdint.h> //.kbv
davidprentice 0:5952bbaff1c6 25
davidprentice 0:5952bbaff1c6 26 char *dtostrf(double val, signed char width, unsigned char prec, char *sout)
davidprentice 0:5952bbaff1c6 27 {
davidprentice 0:5952bbaff1c6 28 //Commented code is the original version
davidprentice 0:5952bbaff1c6 29 /*char fmt[20];
davidprentice 0:5952bbaff1c6 30 sprintf(fmt, "%%%d.%df", width, prec);
davidprentice 0:5952bbaff1c6 31 sprintf(sout, fmt, val);
davidprentice 0:5952bbaff1c6 32 return sout;*/
davidprentice 0:5952bbaff1c6 33
davidprentice 0:5952bbaff1c6 34 // Handle negative numbers
davidprentice 0:5952bbaff1c6 35 uint8_t negative = 0;
davidprentice 0:5952bbaff1c6 36 if (val < 0.0) {
davidprentice 0:5952bbaff1c6 37 negative = 1;
davidprentice 0:5952bbaff1c6 38 val = -val;
davidprentice 0:5952bbaff1c6 39 }
davidprentice 0:5952bbaff1c6 40
davidprentice 0:5952bbaff1c6 41 // Round correctly so that print(1.999, 2) prints as "2.00"
davidprentice 0:5952bbaff1c6 42 double rounding = 0.5;
davidprentice 0:5952bbaff1c6 43 for (int i = 0; i < prec; ++i) {
davidprentice 0:5952bbaff1c6 44 rounding /= 10.0;
davidprentice 0:5952bbaff1c6 45 }
davidprentice 0:5952bbaff1c6 46
davidprentice 0:5952bbaff1c6 47 val += rounding;
davidprentice 0:5952bbaff1c6 48
davidprentice 0:5952bbaff1c6 49 // Extract the integer part of the number
davidprentice 0:5952bbaff1c6 50 unsigned long int_part = (unsigned long)val;
davidprentice 0:5952bbaff1c6 51 double remainder = val - (double)int_part;
davidprentice 0:5952bbaff1c6 52
davidprentice 0:5952bbaff1c6 53 // Extract digits from the remainder
davidprentice 0:5952bbaff1c6 54 unsigned long dec_part = 0;
davidprentice 0:5952bbaff1c6 55 double decade = 1.0;
davidprentice 0:5952bbaff1c6 56 for (int i = 0; i < prec; i++) {
davidprentice 0:5952bbaff1c6 57 decade *= 10.0;
davidprentice 0:5952bbaff1c6 58 }
davidprentice 0:5952bbaff1c6 59 remainder *= decade;
davidprentice 0:5952bbaff1c6 60 dec_part = (int)remainder;
davidprentice 0:5952bbaff1c6 61
davidprentice 0:5952bbaff1c6 62 if (negative) {
davidprentice 0:5952bbaff1c6 63 sprintf(sout, "-%ld.%0*ld", int_part, prec, dec_part);
davidprentice 0:5952bbaff1c6 64 } else {
davidprentice 0:5952bbaff1c6 65 sprintf(sout, "%ld.%0*ld", int_part, prec, dec_part);
davidprentice 0:5952bbaff1c6 66 }
davidprentice 0:5952bbaff1c6 67 // Handle minimum field width of the output string
davidprentice 0:5952bbaff1c6 68 // width is signed value, negative for left adjustment.
davidprentice 0:5952bbaff1c6 69 // Range -128,127
davidprentice 0:5952bbaff1c6 70 char fmt[129] = "";
davidprentice 0:5952bbaff1c6 71 unsigned int w = width;
davidprentice 0:5952bbaff1c6 72 if (width < 0) {
davidprentice 0:5952bbaff1c6 73 negative = 1;
davidprentice 0:5952bbaff1c6 74 w = -width;
davidprentice 0:5952bbaff1c6 75 } else {
davidprentice 0:5952bbaff1c6 76 negative = 0;
davidprentice 0:5952bbaff1c6 77 }
davidprentice 0:5952bbaff1c6 78
davidprentice 0:5952bbaff1c6 79 if (strlen(sout) < w) {
davidprentice 0:5952bbaff1c6 80 memset(fmt, ' ', 128);
davidprentice 0:5952bbaff1c6 81 fmt[w - strlen(sout)] = '\0';
davidprentice 0:5952bbaff1c6 82 if (negative == 0) {
davidprentice 0:5952bbaff1c6 83 char *tmp = malloc(strlen(sout) + 1);
davidprentice 0:5952bbaff1c6 84 strcpy(tmp, sout);
davidprentice 0:5952bbaff1c6 85 strcpy(sout, fmt);
davidprentice 0:5952bbaff1c6 86 strcat(sout, tmp);
davidprentice 0:5952bbaff1c6 87 free(tmp);
davidprentice 0:5952bbaff1c6 88 } else {
davidprentice 0:5952bbaff1c6 89 // left adjustment
davidprentice 0:5952bbaff1c6 90 strcat(sout, fmt);
davidprentice 0:5952bbaff1c6 91 }
davidprentice 0:5952bbaff1c6 92 }
davidprentice 0:5952bbaff1c6 93
davidprentice 0:5952bbaff1c6 94 return sout;
davidprentice 0:5952bbaff1c6 95 }
davidprentice 0:5952bbaff1c6 96