Merge pull request #69 from alexeikh/pr/fix-file-offset-bits-64

Fix compilation for Android and clean up _FILE_OFFSET_BITS #if-ery

src/operations.cpp

@@ -11,21 +11,45 @@
 //--------------------------------------------------------------------------------------// 
 
 //  define 64-bit offset macros BEFORE including boost/config.hpp (see ticket #5355) 
-#if !(defined(__HP_aCC) && defined(_ILP32) && !defined(_STATVFS_ACPP_PROBLEMS_FIXED))
-#define _FILE_OFFSET_BITS 64 // at worst, these defines may have no effect,
-#endif
-#if !defined(__PGI)
-#define __USE_FILE_OFFSET64 // but that is harmless on Windows and on POSIX
-      // 64-bit systems or on 32-bit systems which don't have files larger 
-      // than can be represented by a traditional POSIX/UNIX off_t type. 
-      // OTOH, defining them should kick in 64-bit off_t's (and thus 
-      // st_size)on 32-bit systems that provide the Large File
-      // Support (LFS)interface, such as Linux, Solaris, and IRIX.
-      // The defines are given before any headers are included to
-      // ensure that they are available to all included headers.
-      // That is required at least on Solaris, and possibly on other
-      // systems as well.
+#if defined(__ANDROID__) && defined(__ANDROID_API__) && __ANDROID_API__ < 24
+// Android fully supports 64-bit file offsets only for API 24 and above.
+//
+// Trying to define _FILE_OFFSET_BITS=64 for APIs below 24
+// leads to compilation failure for one or another reason,
+// depending on target Android API level, Android NDK version,
+// used STL, order of include paths and more.
+// For more information, please see:
+// - https://github.com/boostorg/filesystem/issues/65
+// - https://github.com/boostorg/filesystem/pull/69
+//
+// Android NDK developers consider it the expected behavior.
+// See their official position here:
+// - https://github.com/android-ndk/ndk/issues/501#issuecomment-326447479
+// - https://android.googlesource.com/platform/bionic/+/a34817457feee026e8702a1d2dffe9e92b51d7d1/docs/32-bit-abi.md#32_bit-abi-bugs
+//
+// Thus we do not define _FILE_OFFSET_BITS in such case.
 #else
+// Defining _FILE_OFFSET_BITS=64 should kick in 64-bit off_t's
+// (and thus st_size) on 32-bit systems that provide the Large File
+// Support (LFS) interface, such as Linux, Solaris, and IRIX.
+//
+// At the time of this comment writing (March 2018), on most systems
+// _FILE_OFFSET_BITS=64 definition is harmless:
+// either the definition is supported and enables 64-bit off_t,
+// or the definition is not supported and is ignored, in which case
+// off_t does not change its default size for the target system
+// (which may be 32-bit or 64-bit already).
+// Thus it makes sense to have _FILE_OFFSET_BITS=64 defined by default,
+// instead of listing every system that supports the definition.
+// Those few systems, on which _FILE_OFFSET_BITS=64 is harmful,
+// for example this definition causes compilation failure on those systems,
+// should be exempt from defining _FILE_OFFSET_BITS by adding
+// an appropriate #elif block above with the appropriate comment.
+//
+// _FILE_OFFSET_BITS must be defined before any headers are included
+// to ensure that the definition is available to all included headers.
+// That is required at least on Solaris, and possibly on other
+// systems as well.
 #define _FILE_OFFSET_BITS 64
 #endif
 
@@ -44,7 +68,8 @@
 #include <boost/filesystem/operations.hpp>
 #include <boost/scoped_array.hpp>
 #include <boost/detail/workaround.hpp>
-#include <vector> 
+#include <limits>
+#include <vector>
 #include <cstdlib>     // for malloc, free
 #include <cstring>
 #include <cstdio>      // for remove, rename
@@ -1615,6 +1640,12 @@ namespace detail
   BOOST_FILESYSTEM_DECL
   void resize_file(const path& p, uintmax_t size, system::error_code* ec)
   {
+#   if defined(BOOST_POSIX_API)
+    if (BOOST_UNLIKELY(size > static_cast< uintmax_t >((std::numeric_limits< off_t >::max)()))) {
+      error(system::errc::file_too_large, p, ec, "boost::filesystem::resize_file");
+      return;
+    }
+#   endif
     error(!BOOST_RESIZE_FILE(p.c_str(), size) ? BOOST_ERRNO : 0, p, ec,
       "boost::filesystem::resize_file");
   }