Diff: print.c

Revision:

13:14f56b76aa23

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/print.c	Thu Nov 29 16:52:09 2018 +0000
@@ -0,0 +1,117 @@
+/*
+ * print.c
+ *
+ *  Created on: Jan 6, 2014
+ *      Author: mes
+ */
+
+#include <stdio.h>
+#include <stdint.h>
+#include <math.h>
+
+// from Arduino source
+size_t printNumber(FILE *f, unsigned long n)
+{
+    char buf[8 * sizeof(long) + 1]; // Assumes 8-bit chars plus zero byte.
+    char *str = &buf[sizeof(buf) - 1];
+
+    *str = '\0';
+
+    do {
+        unsigned long m = n;
+        n /= 10;
+        char c = m - 10 * n;
+        *--str = c + '0';
+    } while(n);
+
+    return fputs(str, f);
+}
+
+// from Arduino source
+size_t printInt(FILE *f, long n)
+{
+    int t = 0;
+    if (n < 0) {
+        t = fputc('-', f);
+        n = -n;
+    }
+    return printNumber(f, n) + t;
+}
+
+// from Arduino source
+size_t printFloat(FILE *f, double number, uint8_t digits)
+{
+    size_t n=0;
+
+    if (isnan(number)) return fputs("nan", f);
+    if (isinf(number)) return fputs("inf", f);
+    if (number > 4294967040.0) return fputs("ovf", f);  // constant determined empirically
+    if (number <-4294967040.0) return fputs("ovf", f);  // constant determined empirically
+
+    // Handle negative numbers
+    if (number < 0.0) {
+        n += fputc('-', f);
+        number = -number;
+    }
+
+    // Round correctly so that print(1.999, 2) prints as "2.00"
+    double rounding = 0.5;
+    for (uint8_t i=0; i < digits; ++i)
+        rounding /= 10.0;
+
+    number += rounding;
+
+    // Extract the integer part of the number and print it
+    unsigned long int_part = (unsigned long)number;
+    double remainder = number - (double)int_part;
+    n += printInt(f, int_part);
+
+    // Print the decimal point, but only if there are digits beyond
+    if (digits > 0) {
+        n += fputc('.', f);
+    }
+
+    // Extract digits from the remainder one at a time
+    while (digits-- > 0) {
+        remainder *= 10.0;
+        int toPrint = (int) remainder;
+        n += fputc(toPrint+'0', f);
+        remainder -= toPrint;
+    }
+
+    return n;
+}
+
+size_t printHex(FILE *f, long n, uint8_t digits) {
+    unsigned char c;
+    long mask = 0xf0000000;
+
+    while (mask) {
+        c = (n & mask);
+        // TODO 3: finish this
+        switch (c) {
+        case 0:
+        case 1:
+        case 2:
+        case 3:
+        case 4:
+        case 5:
+        case 6:
+        case 7:
+        case 8:
+        case 9:
+            fputc('0'-c, f);
+            break;
+        case 10:
+        case 11:
+        case 12:
+        case 13:
+        case 14:
+        case 15:
+            fputc('a'-c, f);
+            break;
+        }
+        mask >>= 4;
+    }
+    return 1;
+}