toaruos/kernel/misc/kprintf.c
Kevin Lange 8ed06789ed New debug printing facilities.
- Can now register a userspace file descriptor as the output for kernel
  print statements through kprintf()
- Can set logging levels for debug print messages, which are separate
  from kernel log events and meant to be more readily visible. Log
  events are recorded in a buffer to be viewed later, though nothing
  actually using logging at the moment.
- Serial output is disabled by default now. You can enable it yourself
  by appending the logtoserial argument to the kernel on boot.
2012-09-03 22:35:11 -07:00

174 lines
3.2 KiB
C

/* vim: tabstop=4 shiftwidth=4 noexpandtab
*
* Kernel printf implementation
*
* Simple, painfully lacking, implementation of printf(),
* for the kernel of all things.
*/
#include <system.h>
#include <process.h>
#include <va_list.h>
#include <fs.h>
/*
* Integer to string
*/
static void
parse_num(
unsigned int value,
unsigned int base,
char * buf,
int * ptr
) {
unsigned int n = value / base;
int r = value % base;
if (r < 0) {
r += base;
--n;
}
if (value >= base) {
parse_num(n, base, buf, ptr);
}
buf[*ptr] = (r+'0');
*ptr = *ptr + 1;
}
/*
* Hexadecimal to string
*/
static void
parse_hex(
unsigned int value,
char * buf,
int * ptr
) {
int i = 8;
while (i-- > 0) {
buf[*ptr] = "0123456789abcdef"[(value>>(i*4))&0xF];
*ptr = *ptr + 1;
}
}
/*
* vasprintf()
*/
size_t
vasprintf(char * buf, const char *fmt, va_list args) {
int i = 0;
char *s;
int ptr = 0;
int len = strlen(fmt);
for ( ; i < len && fmt[i]; ++i) {
if (fmt[i] != '%') {
buf[ptr++] = fmt[i];
continue;
}
/* fmt[i] == '%' */
switch (fmt[++i]) {
case 's': /* String pointer -> String */
s = (char *)va_arg(args, char *);
while (*s) {
buf[ptr++] = *s++;
}
break;
case 'c': /* Single character */
buf[ptr++] = (char)va_arg(args, int);
break;
case 'x': /* Hexadecimal number */
parse_hex((unsigned long)va_arg(args, unsigned long), buf, &ptr);
break;
case 'd': /* Decimal number */
parse_num((unsigned long)va_arg(args, unsigned long), 10, buf, &ptr);
break;
case '%': /* Escape */
buf[ptr++] = '%';
break;
default: /* Nothing at all, just dump it */
buf[ptr++] = fmt[i];
break;
}
}
/* Ensure the buffer ends in a null */
buf[ptr] = '\0';
return ptr;
}
short kprint_to_serial = 0;
void * kprint_to_file = NULL;
/**
* (Kernel) Print a formatted string.
* %s, %c, %x, %d, %%
*
* @param fmt Formatted string to print
* @param ... Additional arguments to format
*/
#ifndef EXTREME_KPRINTF_DEBUGGING
int
kprintf(
const char *fmt,
...
) {
char buf[1024] = {-1};
va_list args;
va_start(args, fmt);
int out = vasprintf(buf, fmt, args);
/* We're done with our arguments */
va_end(args);
/* Print that sucker */
if (kprint_to_serial) {
serial_string(buf);
} else {
/* TODO "Registered Ouput Terminal", which is probably *not* the serial output */
/* XXX */
if (kprint_to_file) {
fs_node_t * node = (fs_node_t *)kprint_to_file;
uint32_t out = write_fs(node, node->offset, strlen(buf), (uint8_t *)buf);
node->offset += out;
}
}
return out;
}
#else
int
_kprintf(
char * file,
int line,
const char *fmt,
...
) {
char buf[1024] = {-1};
va_list args;
va_start(args, fmt);
int out = vasprintf(buf, fmt, args);
/* We're done with our arguments */
va_end(args);
/* Print that sucker */
if (buf[strlen(buf)-1] == '\n') {
buf[strlen(buf)-1] = '\0';
serial_string(buf);
char buf2[1024];
sprintf(buf2, " %s:%d\n", file, line);
serial_string(buf2);
} else {
serial_string(buf);
}
return out;
}
#endif
int
sprintf(
char * buf,
const char *fmt,
...
) {
va_list args;
va_start(args, fmt);
int out = vasprintf(buf, fmt, args);
va_end(args);
return out;
}