[compiler-rt] Move __sanitizer_mallinfo to separate header

[leonardchan]

Summary

mallinfo is platform-specific and not specified by either posix or the C standard, but the hwasan interface unconditionally exposes __sanitizer_mallinfo which returns a struct __sanitizer_struct_mallinfo which is defined in sanitizer_platform_limits_posix.h, so this should also be available for fuchsia to provide __sanitizer_mallinfo. Fuchsia doesn't need the rest of what's in sanitizer_platform_limits_posix.h so we can just move it to its own header.

Exposing this and not forcing it to hide behind SANITIZER_INTERCEPT_MALLOPT_AND_MALLINFO fixes the test failures found after landing D145718.

[phosek]

I'm not a big fan of this change since Fuchsia is not POSIX and most of this files isn't useful on Fuchsia. mallinfo is also not specified by neither POSIX nor C standard. Would it be possible to move the definition of __sanitizer_struct_mallinfo to a separate header file?

[leonardchan]

In D147092#4229150, @phosek wrote:

I'm not a big fan of this change since Fuchsia is not POSIX and most of this files isn't useful on Fuchsia. mallinfo is also not specified by neither POSIX nor C standard. Would it be possible to move the definition of __sanitizer_struct_mallinfo to a separate header file?

Something like this?

[mcgrathr]

I agree that isolating things away from an #if-ridden grab-bag is the cleanest approach here.

compiler-rt/lib/sanitizer_common/sanitizer_mallinfo.h

20

It's usually a good idea to put blank lines around the # directive lines.

compiler-rt/lib/sanitizer_common/sanitizer_mallinfo.h

+//===-- sanitizer_mallinfo.h ----------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of Sanitizer common code.
+//
+// Definition for mallinfo on different platforms.
+//===----------------------------------------------------------------------===//
+
+#ifndef SANITIZER_MALLINFO_H
+#define SANITIZER_MALLINFO_H
+
+#include "sanitizer_internal_defs.h"
+#include "sanitizer_platform.h"
+
+#if SANITIZER_ANDROID
+struct __sanitizer_struct_mallinfo {
+  uptr v[10];
+};
+#elif SANITIZER_LINUX || SANITIZER_APPLE || SANITIZER_FUCHSIA
+struct __sanitizer_struct_mallinfo {
+  int v[10];
+};
+#endif
+
+#endif  // SANITIZER_MALLINFO_H

compiler-rt/lib/sanitizer_common/sanitizer_platform_limits_posix.h

 
 #ifndef SANITIZER_PLATFORM_LIMITS_POSIX_H
 #define SANITIZER_PLATFORM_LIMITS_POSIX_H
 
 #if SANITIZER_LINUX || SANITIZER_APPLE
 
 #include "sanitizer_internal_defs.h"
 #include "sanitizer_platform.h"
+#include "sanitizer_mallinfo.h"
 
 #if SANITIZER_APPLE
 #include <sys/cdefs.h>
 #if !__DARWIN_ONLY_64_BIT_INO_T
 #define SANITIZER_HAS_STAT64 1
 #define SANITIZER_HAS_STATFS64 1
 #else
 #define SANITIZER_HAS_STAT64 0

 #elif SANITIZER_ANDROID && !defined(_LP64)
   int data;
 #elif SANITIZER_LINUX
   uptr data[4];
 #endif
 };
 #endif // SANITIZER_LINUX
 
-#if SANITIZER_ANDROID
-struct __sanitizer_struct_mallinfo {
-  uptr v[10];
-};
-#endif
-
 #if SANITIZER_LINUX && !SANITIZER_ANDROID
-struct __sanitizer_struct_mallinfo {
-  int v[10];
-};
-
 extern unsigned struct_ustat_sz;
 extern unsigned struct_rlimit64_sz;
 extern unsigned struct_statvfs64_sz;
 
 struct __sanitizer_ipc_perm {
   int __key;
   int uid;
   int gid;