source: issm/trunk-jpl/src/c/shared/Exceptions/exprintf.cpp@ 12500

/*!\file:  exprintf
 * \brief this is a modification of the sprintf function. 
 * Instead of returning an int, it will return the char* itself.
 * The advantage is to be able to do things like: 
 * ErrorException(exprintf("%s%i\n","test failed for id:",id));
 */ 


#include <stdarg.h>
#include <stdio.h>
#include "../Alloc/xNewDelete.h"
#include "../Alloc/alloc.h"

char* exprintf(const char* format,...){

        /*returned string: */
        char *buffer = NULL;
        int   n,size = 100;
        int   string_size;

        //variable list of arguments
        va_list args;

        while(true){

                /*allocate buffer for given string size*/
                buffer=xNew<char>(size);

                /* Try to print in the allocated space. */
                va_start(args, format);
#ifndef WIN32
                n=vsnprintf(buffer,size,format,args);
#else
                n=vsnprintf(buffer,size,format,args);
#endif
                va_end(args);

                /* If that worked, return the string. */
                if(n>-1 && n<size) break;

                /* Else try again with more space. */
                if(n>-1)   /* glibc 2.1 */
                 size=n+1; /* precisely what is needed */
                else       /* glibc 2.0 */
                 size*=2;  /* twice the old size */

                xDelete<char>(buffer);
        }

        return buffer;
}