/* Returns bytes written, negative on error */
int vfprintf(rd_t rd, char *fmt, va_list ap, int (*puts_fn)(rd_t,char*), int (*putc_fn)(rd_t,char)) {
int total = 0;
/* We buffer data here as long as possible, because the actual puts/putc functions tend to be slow
* and the fewer calls we can make, the better. */
char holding[32];
int hold_count = 0;
const int hold_len = sizeof(holding)/sizeof(holding[0]);
holding[0] = '\0';
int ret;
while (*fmt) {
if (*fmt == '%') {
switch (*(++fmt)) {
case 'x': {
/* Hex */
uint32_t hex = va_arg(ap, uint32_t);
char buf[12];
uitoa(hex, buf, 9, 16);
ret = holding_flush(holding, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
ret = puts_fn(rd, buf);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
break;
}
case 'i': case 'd': {
int num = va_arg(ap, int);
char buf[9]; /* 7 digits in INT_MAX + '-' and '\0' */
itoa(num, buf, 12, 10);
ret = holding_flush(holding, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
ret = puts_fn(rd, buf);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
break;
}
case 'u': {
uint32_t num = va_arg(ap, uint32_t);
char buf[9]; /* 7 digits in INT_MAX + '-' and '\0' */
uitoa(num, buf, 12, 10);
ret = holding_flush(holding, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
ret = puts_fn(rd, buf);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
break;
}
case 'f': {
float num = (float) va_arg(ap, double);
char buf[20];
ftoa(num, 0.0001f, buf, 20);
ret = holding_flush(holding, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
ret = puts_fn(rd, buf);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
break;
}
case 'c': {
char letter = (char) va_arg(ap, uint32_t);
ret = holding_push(letter, holding, hold_len, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
break;
}
case 's': {
char *s = va_arg(ap, char*);
ret = holding_flush(holding, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
ret = puts_fn(rd, s);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
break;
}
case '%': { /* Just print a % */
ret = holding_push('%', holding, hold_len, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
break;
}
default: {
ret = holding_push('%', holding, hold_len, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
ret = holding_push(*fmt, holding, hold_len, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
}
}
fmt++;
}
else {
ret = holding_push(*fmt++, holding, hold_len, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
}
}
}
else {
return ret;
}
}
}
fmt++;
}
else {
ret = holding_push(*fmt++, holding, hold_len, &hold_count, dev);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
}
}
ret = holding_flush(holding, &hold_count, dev);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
return total;
}
}
else {
return ret;
}
}
}
fmt++;
}
else {
ret = holding_push(*fmt++, holding, hold_len, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
}
}
ret = holding_flush(holding, &hold_count, rd, puts_fn);
if (ret >= 0) {
total += ret;
}
else {
return ret;
}
return total;
}
