libui/common/errors.c

// 12 may 2019
#include <stdarg.h>
#include <stdio.h>
#include "ui.h"
#include "uipriv.h"

#define internalErrorPrefix "libui internal error"
// TODO add debugging advice?
#define internalErrorSuffix "This likely means there is a bug in libui itself. Contact the libui authors."

void uiprivInternalError(const char *fmt, ...)
{
	va_list ap;
	char buf[256];
	int n;

	va_start(ap, fmt);
	n = vsnprintf(buf, 256, fmt, ap);
	va_end(ap);
	if (n < 0)
		uiprivReportError(internalErrorPrefix, "internal error string has encoding error", internalErrorSuffix, true);
	if (n >= 256)
		uiprivReportError(internalErrorPrefix, "internal error string too long", internalErrorSuffix, true);
	uiprivReportError(internalErrorPrefix, buf, internalErrorSuffix, true);
}

static const char *messages[] = {
	[uiprivProgrammerErrorWrongStructSize] = "wrong size %zu for %s",
	[uiprivProgrammerErrorIndexOutOfRange] = "index %d out of range in %s()",
	[uiprivProgrammerErrorNullPointer] = "invalid null pointer for %s passed into %s()",
	[uiprivProgrammerErrorIntIDNotFound] = "%s identifier %d not found in %s()",
};

static void prepareProgrammerError(char *buf, int size, unsigned int which, va_list ap)
{
	int n;

	if (which >= uiprivNumProgrammerErrors)
		uiprivInternalError("bad programmer error value %u", which);
	n = vsnprintf(buf, size, messages[which], ap);
	if (n < 0)
		uiprivInternalError("programmer error string for %u has encoding error", which);
	if (n >= size)
		uiprivInternalError("programmer error string for %u too long (%d)", which, n);
}

#define programmerErrorPrefix "libui programmer error"
// TODO add debugging advice?
#define programmerErrorSuffix "This likely means you are using libui incorrectly. Check your source code and try again. If you have received this warning in error, contact the libui authors."

void uiprivProgrammerError(unsigned int which, ...)
{
	va_list ap;
	char buf[256];

	va_start(ap, which);
	prepareProgrammerError(buf, 256, which, ap);
	va_end(ap);
	uiprivReportError(programmerErrorPrefix, buf, programmerErrorSuffix, false);
}