myprintf.c

S3C4510(ARM7)开发板bootloader实现及板载硬件测试代码

#include "myprintf.h"

#ifndef TARGET_PC

#include <stdarg.h>

int putchar(int ch)
{
	int res;
	static int uart_init_done = 0;

	if (!uart_init_done)
	{
			uart_init(UART0_BASE, BAUD_19200);
	 		uart_init_done = 1;
	}
	
	res = uart_putchar(ch);
	
	return res;
}

int puts(const char *str)
{
	int res;
	static int uart_init_done = 0;

	if (!uart_init_done)
	{
			uart_init(UART0_BASE, BAUD_19200);
	 		uart_init_done = 1;
	}
	
	res = uart_puts(str);
	
	return res;
}

static char *itoa(int num, int base)
{
     static char buf[20];
     char temp;
     int i=0, j=0, digit;

     if (base != 10
	 && base != 8
	 && base != 16) {
	  puts("unsupported conversion\n");
	  //exit(1);
	  return (char *)0;
     }
     
     while (num) {
	  digit = num % base;
	  num /= base;
	  if (digit > 9)
	       buf[i++] = digit - 10 + 'a';
	  else
	       buf[i++] = digit + '0';
     }
     buf[i] = 0;
     while (j < i/2) {
	  temp = buf[j];
	  buf[j] = buf[i-1-j];
	  buf[i-1-j] = temp;
	  j++;
     }

     return buf;
}

int printf(const char *format, ...)
{
     va_list ap;
     char c, ch, *p;
     int i;
     enum state_t {LITERAL, DIRECTIVE};
     enum state_t state = LITERAL;

		 static int uart_init_done = 0;

		 if (!uart_init_done)
		 {
		 		uart_init(UART0_BASE, BAUD_19200);
		 		uart_init_done = 1;
		 }		 
		 
     va_start(ap, format);
     while ((c = (*(format++))) != '\0') {
	  switch(c) {
	  case '%':
	       if (state == LITERAL) {
		    state = DIRECTIVE;
		    break;
	       }
	       /* state == DIRECTIVE */
	       putchar(c);
	       state = LITERAL;
	       break;
	  case 'c':
	       if (state == LITERAL) {
		    putchar(c);
		    break;
	       }
	       /* state == DIRECTIVE */
	       /* char is promoted to int when passed through ... */
	       ch = va_arg(ap, int);
	       putchar(ch);
	       state = LITERAL;
	       break;
	  case 's':
	       if (state == LITERAL) {
		    putchar(c);
		    break;
	       }
	       /* state == DIRECTIVE */
	       p = va_arg(ap, char *);
	       puts(p);
	       state = LITERAL;
	       break;
	  case 'd':
	       if (state == LITERAL) {
		    putchar(c);
		    break;
	       }
	       /* state == DIRECTIVE */
	       i = va_arg(ap, int);
	       puts(itoa(i, 10));
	       state = LITERAL;
	       break;
	  case 'o':
	       if (state == LITERAL) {
		    putchar(c);
		    break;
	       }
	       /* state == DIRECTIVE */
	       i = va_arg(ap, int);
	       puts(itoa(i, 8));
	       state = LITERAL;
	       break;
	  case 'x':
	       if (state == LITERAL) {
		    putchar(c);
		    break;
	       }
	       /* state == DIRECTIVE */
	       i = va_arg(ap, int);
	       puts(itoa(i, 16));
	       state = LITERAL;
	       break;
	  default:
	       if (state == LITERAL) {
		    putchar(c);
		    break;
	       }
	       /* state == DIRECTIVE */
	       puts("unsupported directive\n");
	       //exit(1);
	       return -1;
	  }
     }
     
     va_end(ap);     
     return 0;
}

#endif /* !define TARGET_PC */

static void delay(int count)
{
	int i;
	
	while (count--)
		for (i = 0; i < 65535; i++){;}
}

void printfdemo(void)
{		 
		 int i;
		
		 printf("demo for myprintf\r\n");
     for(i = 0; i < 5; i++)
     {
     		printf("%cc\t%%%s\n%d %o %x\r\n", 'A', "hello world", 15, 15, 15);    
     		delay(20);
     }
     printf("test ok\n");
     
     return;
}