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#include "xsnprintf.h"
#include <assert.h>
#include <limits.h>
#include <stdio.h>
size_t
xvsnprintf(char *buf, size_t n, const char *format, va_list ap)
{
assert(n <= INT_MAX);
int len = vsnprintf(buf, n, format, ap);
/*
* ISO C11 ยง7.21.6.5 states:
* "The snprintf function returns the number of characters that
* would have been written had n been sufficiently large, not
* counting the terminating null character, or a negative value
* if an encoding error occurred. Thus, the null-terminated output
* has been completely written if and only if the returned value
* is nonnegative and less than n."
*/
assert(len >= 0);
assert(len < (int)n);
return (size_t)len;
}
size_t
xsnprintf(char *buf, size_t n, const char *format, ...)
{
va_list ap;
va_start(ap, format);
size_t len = xvsnprintf(buf, n, format, ap);
va_end(ap);
return len;
}
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