From 2b021e10664c3938249eb18b48eeac253cbb3e20 Mon Sep 17 00:00:00 2001
From: Elliott Hughes <enh@google.com>
Date: Tue, 19 Aug 2014 17:00:33 -0700
Subject: [PATCH] Add <stdio_ext.h> for elfutils.

Bug: 17139679
Change-Id: I1605ac382dbb6f23b2d874dbb9769f3cde4a6a99
---
 libc/Android.mk          |   1 +
 libc/include/stdio.h     |   5 ++
 libc/include/stdio_ext.h |  54 ++++++++++++++++
 libc/stdio/stdio_ext.cpp |  96 ++++++++++++++++++++++++++++
 tests/Android.mk         |   1 +
 tests/stdio_ext_test.cpp | 133 +++++++++++++++++++++++++++++++++++++++
 6 files changed, 290 insertions(+)
 create mode 100644 libc/include/stdio_ext.h
 create mode 100644 libc/stdio/stdio_ext.cpp
 create mode 100644 tests/stdio_ext_test.cpp

diff --git a/libc/Android.mk b/libc/Android.mk
index 937f741d5..c268a87b8 100644
--- a/libc/Android.mk
+++ b/libc/Android.mk
@@ -62,6 +62,7 @@ libc_common_src_files := \
     bionic/system_properties_compat.c \
     stdio/snprintf.c\
     stdio/sprintf.c \
+    stdio/stdio_ext.cpp \
 
 # Fortify implementations of libc functions.
 libc_common_src_files += \
diff --git a/libc/include/stdio.h b/libc/include/stdio.h
index 516f8cb10..8727a9fa2 100644
--- a/libc/include/stdio.h
+++ b/libc/include/stdio.h
@@ -343,6 +343,11 @@ int	 setlinebuf(FILE *);
 int	 vasprintf(char ** __restrict, const char * __restrict,
     __va_list)
 		__printflike(2, 0);
+
+void clearerr_unlocked(FILE*);
+int feof_unlocked(FILE*);
+int ferror_unlocked(FILE*);
+
 __END_DECLS
 
 /*
diff --git a/libc/include/stdio_ext.h b/libc/include/stdio_ext.h
new file mode 100644
index 000000000..f299e54e2
--- /dev/null
+++ b/libc/include/stdio_ext.h
@@ -0,0 +1,54 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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.
+ */
+
+#ifndef _STDIO_EXT_H
+#define _STDIO_EXT_H
+
+#include <sys/cdefs.h>
+#include <stdio.h>
+
+#define FSETLOCKING_QUERY 0
+#define FSETLOCKING_INTERNAL 1
+#define FSETLOCKING_BYCALLER 2
+
+__BEGIN_DECLS
+
+size_t __fbufsize(FILE*);
+int __freading(FILE*);
+int __fwriting(FILE*);
+int __freadable(FILE*);
+int __fwritable(FILE*);
+int __flbf(FILE*);
+void __fpurge(FILE*);
+size_t __fpending(FILE*);
+void _flushlbf(void);
+int __fsetlocking(FILE*, int);
+
+__END_DECLS
+
+#endif /* _STDIO_EXT_H */
diff --git a/libc/stdio/stdio_ext.cpp b/libc/stdio/stdio_ext.cpp
new file mode 100644
index 000000000..bfdecb81c
--- /dev/null
+++ b/libc/stdio/stdio_ext.cpp
@@ -0,0 +1,96 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *  * Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *  * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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
+ * COPYRIGHT OWNER 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.
+ */
+
+#include <stdio_ext.h>
+
+#include <stdio.h>
+#include "local.h"
+
+#define FSETLOCKING_QUERY 0
+#define FSETLOCKING_INTERNAL 1
+#define FSETLOCKING_BYCALLER 2
+
+size_t __fbufsize(FILE* fp) {
+  return fp->_bf._size;
+}
+
+/* For a _SRW stream, we don't know whether we last read or wrote.
+int __freading(FILE* fp) {
+  return (fp->_flags & _SRD) != 0 || ...;
+}
+*/
+
+/* For a _SRW stream, we don't know whether we last read or wrote.
+int __fwriting(FILE*) {
+  return (fp->_flags & _SWR) != 0 || ...;
+}
+*/
+
+int __freadable(FILE* fp) {
+  return (fp->_flags & (__SRD|__SRW)) != 0;
+}
+
+int __fwritable(FILE* fp) {
+  return (fp->_flags & (__SWR|__SRW)) != 0;
+}
+
+int __flbf(FILE* fp) {
+  return (fp->_flags & __SLBF) != 0;
+}
+
+void __fpurge(FILE* fp) {
+  fpurge(fp);
+}
+
+size_t __fpending(FILE* fp) {
+  return fp->_p - fp->_bf._base;
+}
+
+void _flushlbf() {
+  // If we flush all streams, we know we've flushed all the line-buffered streams.
+  fflush(NULL);
+}
+
+int __fsetlocking(FILE*, int) {
+  // We don't currently have an implementation that would obey this,
+  // so make setting the state a no-op and always return "we handle locking for you".
+  // http://b/17154740 suggests ways we could fix this.
+  return FSETLOCKING_INTERNAL;
+}
+
+void clearerr_unlocked(FILE* fp) {
+  return __sclearerr(fp);
+}
+
+int feof_unlocked(FILE* fp) {
+  return __sfeof(fp);
+}
+
+int ferror_unlocked(FILE* fp) {
+  return __sferror(fp);
+}
diff --git a/tests/Android.mk b/tests/Android.mk
index b370b92c1..ef33afcd8 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -92,6 +92,7 @@ libBionicStandardTests_src_files := \
     stdatomic_test.cpp \
     stdint_test.cpp \
     stdio_test.cpp \
+    stdio_ext_test.cpp \
     stdlib_test.cpp \
     string_test.cpp \
     strings_test.cpp \
diff --git a/tests/stdio_ext_test.cpp b/tests/stdio_ext_test.cpp
new file mode 100644
index 000000000..3dbc485a6
--- /dev/null
+++ b/tests/stdio_ext_test.cpp
@@ -0,0 +1,133 @@
+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio_ext.h>
+
+#include <gtest/gtest.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <math.h>
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <wchar.h>
+#include <locale.h>
+
+#include "TemporaryFile.h"
+
+TEST(stdio_ext, __fbufsize) {
+  FILE* fp = fopen("/proc/version", "r");
+
+  char buf[128];
+
+  ASSERT_EQ(0, setvbuf(fp, buf, _IOFBF, 1));
+  ASSERT_EQ(1U, __fbufsize(fp));
+
+  ASSERT_EQ(0, setvbuf(fp, buf, _IOFBF, 8));
+  ASSERT_EQ(8U, __fbufsize(fp));
+
+  fclose(fp);
+}
+
+TEST(stdio_ext, __flbf) {
+  FILE* fp = fopen("/proc/version", "r");
+
+  ASSERT_FALSE(__flbf(fp));
+
+  char buf[128];
+  ASSERT_EQ(0, setvbuf(fp, buf, _IOLBF, sizeof(buf)));
+
+  ASSERT_TRUE(__flbf(fp));
+
+  fclose(fp);
+}
+
+TEST(stdio_ext, __fpending) {
+  FILE* fp = fopen("/dev/null", "w");
+  ASSERT_EQ(0U, __fpending(fp));
+  ASSERT_EQ('x', fputc('x', fp));
+  ASSERT_EQ(1U, __fpending(fp));
+  ASSERT_EQ('y', fputc('y', fp));
+  ASSERT_EQ(2U, __fpending(fp));
+  fflush(fp);
+  ASSERT_EQ(0U, __fpending(fp));
+  fclose(fp);
+}
+
+TEST(stdio_ext, __fpurge) {
+  FILE* fp = tmpfile();
+
+  ASSERT_EQ('a', fputc('a', fp));
+  ASSERT_EQ(1U, __fpending(fp));
+  __fpurge(fp);
+  ASSERT_EQ(0U, __fpending(fp));
+
+  ASSERT_EQ('b', fputc('b', fp));
+  ASSERT_EQ('\n', fputc('\n', fp));
+  ASSERT_EQ(2U, __fpending(fp));
+
+  rewind(fp);
+
+  char buf[16];
+  char* s = fgets(buf, sizeof(buf), fp);
+  ASSERT_TRUE(s != NULL);
+  ASSERT_STREQ("b\n", s);
+
+  fclose(fp);
+}
+
+TEST(stdio_ext, _flushlbf) {
+  FILE* fp = fopen("/dev/null", "w");
+
+  char buf[128];
+  ASSERT_EQ(0, setvbuf(fp, buf, _IOLBF, sizeof(buf)));
+
+  ASSERT_EQ('a', fputc('a', fp));
+  ASSERT_EQ(1U, __fpending(fp));
+
+  _flushlbf();
+
+  ASSERT_EQ(0U, __fpending(fp));
+
+  fclose(fp);
+}
+
+TEST(stdio_ext, __freadable__fwritable) {
+  FILE* fp = fopen("/dev/null", "r");
+  ASSERT_TRUE(__freadable(fp));
+  ASSERT_FALSE(__fwritable(fp));
+  fclose(fp);
+
+  fp = fopen("/dev/null", "w");
+  ASSERT_FALSE(__freadable(fp));
+  ASSERT_TRUE(__fwritable(fp));
+  fclose(fp);
+
+  fp = fopen("/dev/null", "w+");
+  ASSERT_TRUE(__freadable(fp));
+  ASSERT_TRUE(__fwritable(fp));
+  fclose(fp);
+}
+
+TEST(stdio_ext, __fsetlocking) {
+  FILE* fp = fopen("/proc/version", "r");
+  // Android doesn't actually support the other modes.
+  ASSERT_EQ(FSETLOCKING_INTERNAL, __fsetlocking(fp, FSETLOCKING_QUERY));
+  fclose(fp);
+}