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#include "output.h"
#include "printf.h" 
 
#include <util/generic/scope.h> 
#include <util/memory/tempbuf.h> 
#include <util/generic/yexception.h> 
 
size_t Printf(IOutputStream& out, const char* fmt, ...) {
    va_list lst; 
    va_start(lst, fmt); 
 
    Y_DEFER { 
        va_end(lst); 
    }; 
 
    return Printf(out, fmt, lst); 
} 
 
static inline size_t TryPrintf(void* ptr, size_t len, IOutputStream& out, const char* fmt, va_list params) {
    va_list lst; 
    va_copy(lst, params); 
    const int ret = vsnprintf((char*)ptr, len, fmt, lst); 
    va_end(lst); 
 
    if (ret < 0) { 
        return len; 
    } 
 
    if ((size_t)ret < len) { 
        out.Write(ptr, (size_t)ret); 
    } 
 
    return (size_t)ret; 
} 
 
size_t Printf(IOutputStream& out, const char* fmt, va_list params) {
    size_t guess = 0; 
 
    while (true) { 
        TTempBuf tmp(guess); 
        const size_t ret = TryPrintf(tmp.Data(), tmp.Size(), out, fmt, params); 
 
        if (ret < tmp.Size()) { 
            return ret; 
        } 
 
        guess = Max(tmp.Size() * 2, ret + 1); 
    } 
 
    return 0; 
}