git

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#include "../git-compat-util.h"
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/*
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 * The size parameter specifies the available space, i.e. includes
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 * the trailing NUL byte; but Windows's vsnprintf uses the entire
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 * buffer and avoids the trailing NUL, should the buffer be exactly
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 * big enough for the result. Defining SNPRINTF_SIZE_CORR to 1 will
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 * therefore remove 1 byte from the reported buffer size, so we
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 * always have room for a trailing NUL byte.
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 */
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#ifndef SNPRINTF_SIZE_CORR
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#if defined(WIN32) && (!defined(__GNUC__) || __GNUC__ < 4) && (!defined(_MSC_VER) || _MSC_VER < 1900)
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#define SNPRINTF_SIZE_CORR 1
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#else
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#define SNPRINTF_SIZE_CORR 0
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#endif
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#endif
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#undef vsnprintf
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int git_vsnprintf(char *str, size_t maxsize, const char *format, va_list ap)
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{
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	va_list cp;
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	char *s;
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	int ret = -1;
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	if (maxsize > 0) {
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		va_copy(cp, ap);
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		ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, cp);
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		va_end(cp);
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		if (ret == maxsize-1)
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			ret = -1;
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		/* Windows does not NUL-terminate if result fills buffer */
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		str[maxsize-1] = 0;
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	}
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	if (ret != -1)
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		return ret;
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	s = NULL;
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	if (maxsize < 128)
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		maxsize = 128;
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	while (ret == -1) {
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		maxsize *= 4;
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		str = realloc(s, maxsize);
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		if (! str)
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			break;
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		s = str;
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		va_copy(cp, ap);
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		ret = vsnprintf(str, maxsize-SNPRINTF_SIZE_CORR, format, cp);
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		va_end(cp);
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		if (ret == maxsize-1)
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			ret = -1;
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	}
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	free(s);
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	return ret;
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}
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int git_snprintf(char *str, size_t maxsize, const char *format, ...)
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{
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	va_list ap;
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	int ret;
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	va_start(ap, format);
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	ret = git_vsnprintf(str, maxsize, format, ap);
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	va_end(ap);
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	return ret;
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}
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