/* APIs to write to sys.stdout or sys.stderr using a printf-like interface.
   Adapted from code submitted by Just van Rossum.

   PySys_WriteStdout(format, ...)
   PySys_WriteStderr(format, ...)

      The first function writes to sys.stdout; the second to sys.stderr.  When
      there is a problem, they write to the real (C level) stdout or stderr;
      no exceptions are raised.

      Both take a printf-style format string as their first argument followed
      by a variable length argument list determined by the format string.

      *** WARNING ***

      The format should limit the total size of the formatted output string to
      1000 bytes.  In particular, this means that no unrestricted "%s" formats
      should occur; these should be limited using "%.<N>s where <N> is a
      decimal number calculated so that <N> plus the maximum size of other
      formatted text does not exceed 1000 bytes.  Also watch out for "%f",
      which can print hundreds of digits for very large numbers.

 */

static void
mywrite(char *name, FILE *fp, const char *format, va_list va)
{
	PyObject *file;
	PyObject *error_type, *error_value, *error_traceback;

	PyErr_Fetch(&error_type, &error_value, &error_traceback);
	file = PySys_GetObject(name);
	if (file == NULL || PyFile_AsFile(file) == fp)
		vfprintf(fp, format, va);
	else {
		char buffer[1001];
		const int written = PyOS_vsnprintf(buffer, sizeof(buffer),
						   format, va);
		if (PyFile_WriteString(buffer, file) != 0) {
			PyErr_Clear();
			fputs(buffer, fp);
		}
		if (written < 0 || (size_t)written >= sizeof(buffer)) {
			const char *truncated = "... truncated";
			if (PyFile_WriteString(truncated, file) != 0) {
				PyErr_Clear();
				fputs(truncated, fp);
			}
		}
	}
	PyErr_Restore(error_type, error_value, error_traceback);
}

void
PySys_WriteStdout(const char *format, ...)
{
	va_list va;

	va_start(va, format);
	mywrite("stdout", stdout, format, va);
	va_end(va);
}

void
PySys_WriteStderr(const char *format, ...)
{
	va_list va;

	va_start(va, format);
	mywrite("stderr", stderr, format, va);
	va_end(va);
}