求sprintf的开源代码

求sprintf的开源代码

是c。主要是va_list。用来支持可变参数的。这个是关键。在百度上查查可变参数怎么弄吧，别的都很常规

#include
#include
#include
#include
#include
#include
#include
#define MAXSTR INT_MAX

#ifndef _COUNT_
int __cdecl sprintf (
char *string,
const char *format,
...
)
#else
int __cdecl _snprintf (
char *string,
size_t count,
const char *format,
...
)
#endif
{
FILE str;
REG1 FILE *outfile = &str;
va_list arglist;
REG2 int retval;
va_start(arglist, format);
_ASSERTE(string != NULL);
_ASSERTE(format != NULL);
outfile-> _flag = _IOWRT|_IOSTRG;
outfile-> _ptr = outfile-> _base = string;
#ifndef _COUNT_
outfile-> _cnt = MAXSTR;
#else
outfile-> _cnt = count;
#endif
retval = _output(outfile,format,arglist);
_putc_lk( '\0 ',outfile);
return(retval);
}