newlib-2.4.0

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

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

@@ -0,0 +1,113 @@
+/*
+ * 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
+<<gets>>---get character string (obsolete, use <<fgets>> instead)
+
+INDEX
+	gets
+INDEX
+	_gets_r
+
+ANSI_SYNOPSIS
+        #include <stdio.h>
+
+	char *gets(char *<[buf]>);
+
+	char *_gets_r(struct _reent *<[reent]>, char *<[buf]>);
+
+TRAD_SYNOPSIS
+	#include <stdio.h>
+
+	char *gets(<[buf]>)
+	char *<[buf]>;
+
+	char *_gets_r(<[reent]>, <[buf]>)
+	struct _reent *<[reent]>;
+	char *<[buf]>;
+
+DESCRIPTION
+	Reads characters from standard input until a newline is found.
+	The characters up to the newline are stored in <[buf]>. The
+	newline is discarded, and the buffer is terminated with a 0.
+
+	This is a @emph{dangerous} function, as it has no way of checking
+	the amount of space available in <[buf]>. One of the attacks
+	used by the Internet Worm of 1988 used this to overrun a
+	buffer allocated on the stack of the finger daemon and
+	overwrite the return address, causing the daemon to execute
+	code downloaded into it over the connection.
+
+	The alternate function <<_gets_r>> is a reentrant version.  The extra
+	argument <[reent]> is a pointer to a reentrancy structure.
+
+
+RETURNS
+	<<gets>> returns the buffer passed to it, with the data filled
+	in. If end of file occurs with some data already accumulated,
+	the data is returned with no other indication. If end of file
+	occurs with no data in the buffer, NULL is returned.
+
+Supporting OS subroutines required: <<close>>, <<fstat>>, <<isatty>>,
+<<lseek>>, <<read>>, <<sbrk>>, <<write>>.
+*/
+
+#include <_ansi.h>
+#include <reent.h>
+#include <stdio.h>
+#include "local.h"
+
+char *
+_DEFUN(_gets_r, (ptr, buf),
+       struct _reent *ptr _AND
+       char *buf)
+{
+  register int c;
+  register char *s = buf;
+  FILE *fp;
+
+  _REENT_SMALL_CHECK_INIT (ptr);
+  fp = _stdin_r (ptr);
+  CHECK_INIT (ptr, fp);
+  _newlib_flockfile_start (fp);
+  while ((c = __sgetc_r (ptr, fp)) != '\n')
+    if (c == EOF)
+      if (s == buf)
+	{
+	  _newlib_flockfile_exit (fp);
+	  return NULL;
+	}
+      else
+	break;
+    else
+      *s++ = c;
+  *s = 0;
+  _newlib_flockfile_end (fp);
+  return buf;
+}
+
+#ifndef _REENT_ONLY
+
+char *
+_DEFUN(gets, (buf),
+       char *buf)
+{
+  return _gets_r (_REENT, buf);
+}
+
+#endif