1 files changed, 197 insertions, 0 deletions

diff --git a/lib/libc/stdio/findfp.c b/lib/libc/stdio/findfp.c
new file mode 100644
index 000000000000..c3bc74bdbcf7
--- /dev/null
+++ b/lib/libc/stdio/findfp.c
@@ -0,0 +1,197 @@
+/*-
+ * 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. All advertising materials mentioning features or use of this software
+ *    must display the following acknowledgement:
+ *	This product includes software developed by the University of
+ *	California, Berkeley and its contributors.
+ * 4. 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)
+#if 0
+static char sccsid[] = "@(#)findfp.c	8.2 (Berkeley) 1/4/94";
+#endif
+static const char rcsid[] =
+  "$FreeBSD$";
+#endif /* LIBC_SCCS and not lint */
+
+#include <sys/param.h>
+#include <unistd.h>
+#include <stdio.h>
+#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include <libc_private.h>
+#include <spinlock.h>
+
+#include "local.h"
+#include "glue.h"
+
+int	__sdidinit;
+
+#define	NDYNAMIC 10		/* add ten more whenever necessary */
+
+#define	std(flags, file) \
+	{0,0,0,flags,file,{0},0,__sF+file,__sclose,__sread,__sseek,__swrite}
+/*	 p r w flags file _bf z  cookie      close    read    seek    write */
+
+				/* the usual - (stdin + stdout + stderr) */
+static FILE usual[FOPEN_MAX - 3];
+static struct glue uglue = { 0, FOPEN_MAX - 3, usual };
+
+FILE __sF[3] = {
+	std(__SRD, STDIN_FILENO),		/* stdin */
+	std(__SWR, STDOUT_FILENO),		/* stdout */
+	std(__SWR|__SNBF, STDERR_FILENO)	/* stderr */
+};
+struct glue __sglue = { &uglue, 3, __sF };
+
+/*
+ * The following kludge is done to ensure enough binary compatibility
+ * with future versions of libc.  Or rather it allows us to work with
+ * libraries that have been built with a newer libc that defines these
+ * symbols and expects libc to provide them.  We only have need to support
+ * i386 and alpha because they are the only "old" systems we have deployed.
+ */
+FILE *__stdinp = &__sF[0];
+FILE *__stdoutp = &__sF[1];
+FILE *__stderrp = &__sF[2];
+
+static struct glue *	moreglue __P((int));
+
+static spinlock_t thread_lock = _SPINLOCK_INITIALIZER;
+#define THREAD_LOCK()	if (__isthreaded) _SPINLOCK(&thread_lock)
+#define THREAD_UNLOCK()	if (__isthreaded) _SPINUNLOCK(&thread_lock)
+
+static struct glue *
+moreglue(n)
+	register int n;
+{
+	register struct glue *g;
+	register FILE *p;
+	static FILE empty;
+
+	g = (struct glue *)malloc(sizeof(*g) + ALIGNBYTES + n * sizeof(FILE));
+	if (g == NULL)
+		return (NULL);
+	p = (FILE *)ALIGN(g + 1);
+	g->next = NULL;
+	g->niobs = n;
+	g->iobs = p;
+	while (--n >= 0)
+		*p++ = empty;
+	return (g);
+}
+
+/*
+ * Find a free FILE for fopen et al.
+ */
+FILE *
+__sfp()
+{
+	register FILE *fp;
+	register int n;
+	register struct glue *g;
+
+	if (!__sdidinit)
+		__sinit();
+	THREAD_LOCK();
+	for (g = &__sglue;; g = g->next) {
+		for (fp = g->iobs, n = g->niobs; --n >= 0; fp++)
+			if (fp->_flags == 0)
+				goto found;
+		if (g->next == NULL && (g->next = moreglue(NDYNAMIC)) == NULL)
+			break;
+	}
+	THREAD_UNLOCK();
+	return (NULL);
+found:
+	fp->_flags = 1;		/* reserve this slot; caller sets real flags */
+	THREAD_UNLOCK();
+	fp->_p = NULL;		/* no current pointer */
+	fp->_w = 0;		/* nothing to read or write */
+	fp->_r = 0;
+	fp->_bf._base = NULL;	/* no buffer */
+	fp->_bf._size = 0;
+	fp->_lbfsize = 0;	/* not line buffered */
+	fp->_file = -1;		/* no file */
+/*	fp->_cookie = <any>; */	/* caller sets cookie, _read/_write etc */
+	fp->_ub._base = NULL;	/* no ungetc buffer */
+	fp->_ub._size = 0;
+	fp->_lb._base = NULL;	/* no line buffer */
+	fp->_lb._size = 0;
+	return (fp);
+}
+
+/*
+ * XXX.  Force immediate allocation of internal memory.  Not used by stdio,
+ * but documented historically for certain applications.  Bad applications.
+ */
+__warn_references(f_prealloc, 
+	"warning: this program uses f_prealloc(), which is not recommended.");
+
+void
+f_prealloc()
+{
+	register struct glue *g;
+	int n;
+
+	n = getdtablesize() - FOPEN_MAX + 20;		/* 20 for slop. */
+	for (g = &__sglue; (n -= g->niobs) > 0 && g->next; g = g->next)
+		/* void */;
+	if (n > 0)
+		g->next = moreglue(n);
+}
+
+/*
+ * exit() calls _cleanup() through *__cleanup, set whenever we
+ * open or buffer a file.  This chicanery is done so that programs
+ * that do not use stdio need not link it all in.
+ *
+ * The name `_cleanup' is, alas, fairly well known outside stdio.
+ */
+void
+_cleanup()
+{
+	/* (void) _fwalk(fclose); */
+	(void) _fwalk(__sflush);		/* `cheating' */
+}
+
+/*
+ * __sinit() is called whenever stdio's internal variables must be set up.
+ */
+void
+__sinit()
+{
+	/* make sure we clean up on exit */
+	__cleanup = _cleanup;		/* conservative */
+	__sdidinit = 1;
+}