gbdk-releases/gbdk-lib/libc/printf.c
2015-01-10 16:25:09 +01:00

106 lines
2.1 KiB
C

/** Simple printf implementation
Again a stub - will use the std one later...
*/
#include <gbdk-lib.h>
#include <stdio.h>
#include <stdarg.h>
#pragma bank=BASE
static void _printn(unsigned u, unsigned base, char issigned,
volatile void (*emitter)(char, void *), void *pData)
{
const char *_hex = "0123456789ABCDEF";
if (issigned && ((int)u < 0)) {
(*emitter)('-', pData);
u = (unsigned)-((int)u);
}
if (u >= base)
_printn(u/base, base, 0, emitter, pData);
(*emitter)(_hex[u%base], pData);
}
/* PENDING: HACK: A bug in 2.96a pulls emitter into registers and then
destroys them. Marking it as volatile stops this.
*/
static void _printf(const char *format, volatile void (*emitter)(char, void *), void *pData, va_list va)
{
while (*format) {
if (*format == '%') {
switch (*++format) {
case 'c': {
char c = va_arg(va, char);
(*emitter)(c, pData);
break;
}
case 'u':
{
unsigned u = va_arg(va, unsigned);
_printn(u, 10, 0, emitter, pData);
break;
}
case 'd':
{
unsigned u = va_arg(va, unsigned);
_printn(u, 10, 1, emitter, pData);
break;
}
case 'x':
{
unsigned u = va_arg(va, unsigned);
_printn(u, 16, 0, emitter, pData);
break;
}
case 's':
{
char *s = va_arg(va, char *);
while (*s) {
(*emitter)(*s, pData);
s++;
}
break;
}
}
}
else {
(*emitter)(*format, pData);
}
format++;
}
}
static void _char_emitter(char c, void *pData)
{
putchar(c);
}
void printf(const char *format, ...) NONBANKED
{
va_list va;
va_start(va, format);
_printf(format, _char_emitter, NULL, va);
}
typedef struct {
char *at;
} _SPRINTF_INFO;
static void _sprintf_emitter(char c, void *pData)
{
/* This way to avoid bugs in sdcc */
*(((_SPRINTF_INFO *)pData)->at) = c;
((_SPRINTF_INFO *)pData)->at++;
}
void sprintf(char *into, const char *format, ...) NONBANKED
{
_SPRINTF_INFO si;
va_list va;
si.at = into;
va_start(va, format);
_printf(format, _sprintf_emitter, &si, va);
_sprintf_emitter('\0', &si);
}