Libc-825.24.tar.gz

[apple/libc.git] / stdio / FreeBSD / makebuf.c

diff --git a/stdio/FreeBSD/makebuf.c b/stdio/FreeBSD/makebuf.c
index 7d90164cdf9a9108429a0c88ba34a7bdd3a57445..17e45e2c33f9750bf6db99b0385300314dc70b9f 100644 (file)
--- a/stdio/FreeBSD/makebuf.c
+++ b/stdio/FreeBSD/makebuf.c
@@ -47,6 +47,9 @@ __FBSDID("$FreeBSD: src/lib/libc/stdio/makebuf.c,v 1.6 2007/01/09 00:28:07 imp E
 #include "libc_private.h"
 #include "local.h"
 
+#define MAXBUFSIZE     (1 << 16)
+#define TTYBUFSIZE     4096
+
 /*
  * Allocate a file buffer, or switch to unbuffered I/O.
  * Per the ANSI C standard, ALL tty devices default to line buffered.
@@ -69,6 +72,12 @@ __smakebuf(fp)
                return;
        }
        flags = __swhatbuf(fp, &size, &couldbetty);
+       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;
@@ -79,8 +88,6 @@ __smakebuf(fp)
        flags |= __SMBF;
        fp->_bf._base = fp->_p = p;
        fp->_bf._size = size;
-       if (couldbetty && isatty(fp->_file))
-               flags |= __SLBF;
        fp->_flags |= flags;
 }
 
@@ -113,8 +120,7 @@ __swhatbuf(fp, bufsize, couldbetty)
         * __sseek is mainly paranoia.)  It is safe to set _blksize
         * unconditionally; it will only be used if __SOPT is also set.
         */
-       *bufsize = st.st_blksize;
-       fp->_blksize = st.st_blksize;
+       fp->_blksize = *bufsize = st.st_blksize > MAXBUFSIZE ? MAXBUFSIZE : st.st_blksize;
        return ((st.st_mode & S_IFMT) == S_IFREG && fp->_seek == __sseek ?
            __SOPT : __SNPT);
 }