printf.c

#include "minicrt.h"

int fputc(int c, FILE* stream)
{

	if(fwrite(&c,1,1,stream) != 1)
	{
	   return EOF;	
	}else{
	   return c;
	} 
}

int fputs(const char* str, FILE * stream)
{

	int len = strlen(str);
	if(fwrite(str, 1, len, stream) != len)
	{
	   return EOF;
	}else{
	   return len;
	}
}

#ifndef WIN32
#define va_list char*
#define va_start(ap,arg) (ap=(va_list)&arg + sizeof(arg))
#define va_arg(ap,t)     (*(t*)((ap+=sizeof(t)) - sizeof(t)))
#define va_end(ap)       (ap=(va_list)0)
#else 
#endif

int vfprintf(FILE* stream, const char* format, va_list arglist)
{
	
	int translating = 0;
	int ret = 0;
	const char* p=0;
	for( p = format; *p!='\0'; ++p)
	{
	   switch(*p)
	   {
		case '%':
		if(!translating)
		{
		   translating=1;
		}
		else 
		   {
			if(fputc('%', stream) < 0)
			{
			   return EOF;	
			}	
			
			++ret;
			translating = 0;
		   }
		break;
		
		case 'd':
		if(translating)
		{
		   char buf[16];
		   translating = 0;
		   itoa(va_arg(arglist,int), buf, 10);
		   if(fputs(buf, stream) < 0)
		   {
			return EOF;
		   }
		
		   ret += strlen(buf);		
		}else if(fputc('d', stream) < 0)
                     {
                         return EOF;
                     }else 
			++ret;
		break;

		case 's':
		if(translating)
		{
		   const char* str = va_arg(arglist, const char*);
		   translating = 0;
		   if(fputs(str, stream) < 0)
			return EOF;
		   ret += strlen(str);	

		 }else if(fputc('s', stream) <0)
		    {
		      return EOF;	
	            }else 		
		       ++ret;
		 break;			
		
		default:
		if(translating)
		  translating = 0;
		
		if(fputc(*p, stream) < 0)
		{
		   return EOF;	
		}else 
		   ++ret;	 
		
		break;	 		
	   }	
	}
	
	return ret;	
}

int printf(const char *format, ...)
{

	va_list(arglist);
	va_start(arglist, format);
	return vfprintf(stdout, format, arglist);	
}


int fprintf(FILE* stream, const char* format, ...)
{
	va_list(arglist);
	va_start(arglist, format);
	return vfprintf(stream, format, arglist);
}