u-boot/lib/tiny-printf.c
Simon Glass 74b1320ae5 tiny-printf: Always print zeroes
At present this does not print zero values in numeric format (hex and
decimal). Add a special case for this.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
Reviewed-by: Tom Rini <trini@konsulko.com>
2016-01-20 19:06:22 -07:00

141 lines
2.0 KiB
C

/*
* Tiny printf version for SPL
*
* Copied from:
* http://www.sparetimelabs.com/printfrevisited/printfrevisited.php
*
* Copyright (C) 2004,2008 Kustaa Nyholm
*
* SPDX-License-Identifier: LGPL-2.1+
*/
#include <common.h>
#include <stdarg.h>
#include <serial.h>
static char *bf;
static char zs;
static void out(char c)
{
*bf++ = c;
}
static void out_dgt(char dgt)
{
out(dgt + (dgt < 10 ? '0' : 'a' - 10));
zs = 1;
}
static void div_out(unsigned int *num, unsigned int div)
{
unsigned char dgt = 0;
while (*num >= div) {
*num -= div;
dgt++;
}
if (zs || dgt > 0)
out_dgt(dgt);
}
int vprintf(const char *fmt, va_list va)
{
char ch;
char *p;
unsigned int num;
char buf[12];
unsigned int div;
while ((ch = *(fmt++))) {
if (ch != '%') {
putc(ch);
} else {
char lz = 0;
char w = 0;
ch = *(fmt++);
if (ch == '0') {
ch = *(fmt++);
lz = 1;
}
if (ch >= '0' && ch <= '9') {
w = 0;
while (ch >= '0' && ch <= '9') {
w = (w * 10) + ch - '0';
ch = *fmt++;
}
}
bf = buf;
p = bf;
zs = 0;
switch (ch) {
case 0:
goto abort;
case 'u':
case 'd':
num = va_arg(va, unsigned int);
if (ch == 'd' && (int)num < 0) {
num = -(int)num;
out('-');
}
if (!num) {
out_dgt(0);
} else {
for (div = 1000000000; div; div /= 10)
div_out(&num, div);
}
break;
case 'x':
num = va_arg(va, unsigned int);
if (!num) {
out_dgt(0);
} else {
for (div = 0x10000000; div; div /= 0x10)
div_out(&num, div);
}
break;
case 'c':
out((char)(va_arg(va, int)));
break;
case 's':
p = va_arg(va, char*);
break;
case '%':
out('%');
default:
break;
}
*bf = 0;
bf = p;
while (*bf++ && w > 0)
w--;
while (w-- > 0)
putc(lz ? '0' : ' ');
if (p) {
while ((ch = *p++))
putc(ch);
}
}
}
abort:
return 0;
}
int printf(const char *fmt, ...)
{
va_list va;
int ret;
va_start(va, fmt);
ret = vprintf(fmt, va);
va_end(va);
return ret;
}