newlib-2.4.0

git-svn-id: svn://kolibrios.org@6536 a494cfbc-eb01-0410-851d-a64ba20cac60

contrib/sdk/sources/newlib/libc/stdio/getc_u.c

@@ -0,0 +1,90 @@
+/*
+ * Copyright (c) 1990 The Regents of the University of California.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms are permitted
+ * provided that the above copyright notice and this paragraph are
+ * duplicated in all such forms and that any documentation,
+ * advertising materials, and other materials related to such
+ * distribution and use acknowledge that the software was developed
+ * by the University of California, Berkeley.  The name of the
+ * University may not be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
+ * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ */
+
+/*
+FUNCTION
+<<getc_unlocked>>---non-thread-safe version of getc (macro)
+
+INDEX
+	getc_unlocked
+INDEX
+	_getc_unlocked_r
+
+SYNOPSIS
+	#include <stdio.h>
+	int getc_unlocked(FILE *<[fp]>);
+
+	#include <stdio.h>
+	int _getc_unlocked_r(FILE *<[fp]>);
+
+DESCRIPTION
+<<getc_unlocked>> is a non-thread-safe version of <<getc>> declared in
+<<stdio.h>>.  <<getc_unlocked>> may only safely be used within a scope
+protected by flockfile() (or ftrylockfile()) and funlockfile().  These
+functions may safely be used in a multi-threaded program if and only
+if they are called while the invoking thread owns the ( FILE *)
+object, as is the case after a successful call to the flockfile() or
+ftrylockfile() functions.  If threads are disabled, then
+<<getc_unlocked>> is equivalent to <<getc>>.
+
+The <<_getc_unlocked_r>> function is simply the reentrant version of
+<<get_unlocked>> which passes an additional reentrancy structure pointer
+argument: <[ptr]>.
+
+RETURNS
+See <<getc>>.
+
+PORTABILITY
+POSIX 1003.1 requires <<getc_unlocked>>.  <<getc_unlocked>> may be
+implemented as a macro, so arguments should not have side-effects.
+
+Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
+<<lseek>>, <<read>>, <<sbrk>>, <<write>>.  */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "%W% (Berkeley) %G%";
+#endif /* LIBC_SCCS and not lint */
+
+#include <_ansi.h>
+#include <stdio.h>
+
+/*
+ * A subroutine version of the macro getc_unlocked.
+ */
+
+#undef getc_unlocked
+
+int
+_DEFUN(_getc_unlocked_r, (ptr, fp),
+       struct _reent *ptr _AND
+       register FILE *fp)
+{
+  /* CHECK_INIT is called (eventually) by __srefill_r.  */
+
+  return __sgetc_r (ptr, fp);
+}
+
+#ifndef _REENT_ONLY
+
+int
+_DEFUN(getc_unlocked, (fp),
+       register FILE *fp)
+{
+  return __sgetc_r (_REENT, fp);
+}
+
+#endif /* !_REENT_ONLY */