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-rw-r--r--newlib/libc/stdio/makebuf.c96
1 files changed, 96 insertions, 0 deletions
diff --git a/newlib/libc/stdio/makebuf.c b/newlib/libc/stdio/makebuf.c
new file mode 100644
index 00000000000..4a09c4d502a
--- /dev/null
+++ b/newlib/libc/stdio/makebuf.c
@@ -0,0 +1,96 @@
+/* No user fns here. Pesch 15apr92. */
+
+/*
+ * 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.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/unistd.h>
+
+#include "local.h"
+
+/*
+ * 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
+ * optimization) right after the _fstat() that finds the buffer size.
+ */
+
+void
+__smakebuf (fp)
+ register FILE *fp;
+{
+ register size_t size, couldbetty;
+ register _PTR p;
+ struct stat st;
+
+ if (fp->_flags & __SNBF)
+ {
+ fp->_bf._base = fp->_p = fp->_nbuf;
+ fp->_bf._size = 1;
+ return;
+ }
+ if (fp->_file < 0 || _fstat_r (fp->_data, fp->_file, &st) < 0)
+ {
+ couldbetty = 0;
+ size = BUFSIZ;
+ /* do not try to optimise fseek() */
+ fp->_flags |= __SNPT;
+ }
+ else
+ {
+ couldbetty = (st.st_mode & S_IFMT) == S_IFCHR;
+#ifdef HAVE_BLKSIZE
+ size = st.st_blksize <= 0 ? BUFSIZ : st.st_blksize;
+#else
+ size = BUFSIZ;
+#endif
+ /*
+ * Optimize fseek() only if it is a regular file.
+ * (The test for __sseek is mainly paranoia.)
+ */
+ if ((st.st_mode & S_IFMT) == S_IFREG && fp->_seek == __sseek)
+ {
+ fp->_flags |= __SOPT;
+#ifdef HAVE_BLKSIZE
+ fp->_blksize = st.st_blksize;
+#else
+ fp->_blksize = 1024;
+#endif
+ }
+ else
+ fp->_flags |= __SNPT;
+ }
+ if ((p = _malloc_r (fp->_data, size)) == NULL)
+ {
+ fp->_flags |= __SNBF;
+ fp->_bf._base = fp->_p = fp->_nbuf;
+ fp->_bf._size = 1;
+ }
+ else
+ {
+ fp->_data->__cleanup = _cleanup_r;
+ fp->_flags |= __SMBF;
+ fp->_bf._base = fp->_p = (unsigned char *) p;
+ fp->_bf._size = size;
+ if (couldbetty && isatty (fp->_file))
+ fp->_flags |= __SLBF;
+ }
+}