--- /dev/null
+++ Libc/Libc-1534.40.2/stdio/FreeBSD/makebuf.c
@@ -0,0 +1,241 @@
+/*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
+ * Copyright (c) 1990, 1993
+ *	The Regents of the University of California.  All rights reserved.
+ *
+ * This code is derived from software contributed to Berkeley by
+ * Chris Torek.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#if defined(LIBC_SCCS) && !defined(lint)
+static char sccsid[] = "@(#)makebuf.c	8.1 (Berkeley) 6/4/93";
+#endif /* LIBC_SCCS and not lint */
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include "namespace.h"
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "un-namespace.h"
+
+#include "libc_private.h"
+#include "local.h"
+#include <xlocale/_stdio.h>
+#include <xlocale/_stdlib.h>
+#include <os/once_private.h>
+
+#ifdef FEATURE_SMALL_STDIOBUF
+# define MAXBUFSIZE	(1 << 12)
+#else
+# define MAXBUFSIZE	(1 << 16)
+#endif
+
+#define TTYBUFSIZE	4096
+#define MAXEVPSIZE 16
+
+static char __fallback_evp[MAXEVPSIZE];
+static char __stdout_evp[MAXEVPSIZE];
+
+static void
+__loadevp(const char* key, char destination[MAXEVPSIZE])
+{
+	char* evp = getenv(key);
+	if (evp != NULL) {
+		strlcpy(destination, evp, MAXEVPSIZE);
+	} else {
+		destination[0] = '\0';
+	}
+}
+
+static void
+__evpinit(void* __unused unused)
+{
+	__loadevp("STDBUF", __fallback_evp);
+	__loadevp("STDBUF1", __stdout_evp);
+}
+
+static char*
+__getevp(int fd)
+{
+	static os_once_t predicate;
+	os_once(&predicate, NULL, __evpinit);
+
+	if (fd == STDOUT_FILENO && __stdout_evp[0] != '\0') {
+		return __stdout_evp;
+	} else if (__fallback_evp[0] != '\0') {
+		return __fallback_evp;
+	} else {
+		return NULL;
+	}
+
+}
+
+/*
+ * Internal routine to determine environment override buffering for a file.
+ *
+ * Sections of the below taken from NetBSD's version of this file under the same license.
+ */
+static int
+__senvbuf(FILE *fp, size_t *bufsize, int *couldbetty)
+{
+	char* evp;
+	char* end;
+	int flags;
+	long size;
+
+	flags = 0; // Default to fully buffered
+
+	if ((evp = __getevp(fp->_file)) == NULL) {
+		return flags;
+	}
+
+	// Look at the first character only to determine buffering mode
+	switch (*evp) {
+		case 'u':
+		case 'U':
+			flags |= __SNBF;
+			break;
+		case 'l':
+		case 'L':
+			flags |= __SLBF;
+			break;
+		case 'f':
+		case 'F':
+			// Default flags is fully buffered
+			break;
+		default:
+			// Unexpected buffering mode, use default fully buffered
+			return flags;
+	}
+	// User specified envrionment defaults have higher priority than tty defaults
+	*couldbetty = 0;
+
+	// Advance the envrionment variable pointer, so we can attempt to parse the number
+	evp++;
+	if (!isdigit(*evp)) {
+		return flags; // No number found, this protects us from negative size values
+	}
+
+	size = strtol_l(evp, &end, 10, LC_C_LOCALE);
+	if (*end != '\0') {
+		return flags;
+	}
+
+	if (size <= 0) {
+		return __SNBF; // Override with unbuffered if the buffer size is 0
+	}
+
+	// We had a non zero buffer, cap it and return the flags;
+	*bufsize = size > MAXBUFSIZE ? MAXBUFSIZE : size;
+	return flags;
+}
+
+/*
+ * Allocate a file buffer, or switch to unbuffered I/O.
+ * Per the ANSI C standard, ALL tty devices default to line buffered.
+ *
+ * As a side effect, we set __SOPT or __SNPT (en/dis-able fseek
+ * optimisation) right after the _fstat() that finds the buffer size.
+ */
+void
+__smakebuf(FILE *fp)
+{
+	void *p;
+	int flags;
+	size_t size;
+	int couldbetty;
+
+	if (fp->_flags & __SNBF) {
+		fp->_bf._base = fp->_p = fp->_nbuf;
+		fp->_bf._size = 1;
+		return;
+	}
+	flags = __swhatbuf(fp, &size, &couldbetty);
+	if (fp->_file >= 0) {
+		flags |= __senvbuf(fp, &size, &couldbetty);
+
+		if (flags & __SNBF) {
+			fp->_flags |= __SNBF;
+			fp->_bf._base = fp->_p = fp->_nbuf;
+			fp->_bf._size = 1;
+			return;
+		}
+	}
+
+	if (couldbetty && isatty(fp->_file)) {
+		flags |= __SLBF;
+		/* st_blksize for ttys is 128K, so make it more reasonable */
+		if (size > TTYBUFSIZE)
+			fp->_blksize = size = TTYBUFSIZE;
+	}
+	if ((p = malloc(size)) == NULL) {
+		fp->_flags |= __SNBF;
+		fp->_bf._base = fp->_p = fp->_nbuf;
+		fp->_bf._size = 1;
+		return;
+	}
+	__cleanup = _cleanup;
+	flags |= __SMBF;
+	fp->_bf._base = fp->_p = p;
+	fp->_bf._size = size;
+	fp->_flags |= flags;
+}
+
+/*
+ * Internal routine to determine `proper' buffering for a file.
+ */
+int
+__swhatbuf(FILE *fp, size_t *bufsize, int *couldbetty)
+{
+	struct stat st;
+
+	if (fp->_file < 0 || _fstat(fp->_file, &st) < 0) {
+		*couldbetty = 0;
+		*bufsize = BUFSIZ;
+		return (__SNPT);
+	}
+
+	/* could be a tty iff it is a character device */
+	*couldbetty = (st.st_mode & S_IFMT) == S_IFCHR;
+	if (st.st_blksize <= 0) {
+		*bufsize = BUFSIZ;
+		return (__SNPT);
+	}
+
+	/*
+	 * Optimise fseek() only if it is a regular file.  (The test for
+	 * __sseek is mainly paranoia.)  It is safe to set _blksize
+	 * unconditionally; it will only be used if __SOPT is also set.
+	 */
+	fp->_blksize = *bufsize = st.st_blksize > MAXBUFSIZE ? MAXBUFSIZE : st.st_blksize;
+	return ((st.st_mode & S_IFMT) == S_IFREG && fp->_seek == __sseek ?
+	    __SOPT : __SNPT);
+}