[libc++] Make LIBCXX_ENABLE_FILESYSTEM fully consistent
Previously, LIBCXX_ENABLE_FILESYSTEM controlled only whether the filesystem
support was compiled into libc++'s library. This commit promotes the
setting to a first-class option like LIBCXX_ENABLE_LOCALIZATION, where
the whole library is aware of the setting and features that depend on
<filesystem> won't be provided at all. The test suite is also properly
annotated such that tests that depend on <filesystem> are disabled when
the library doesn't support it.
This is an alternative to https://llvm.org/D94824, but also an improvement
along the lines of LIBCXX_ENABLE_LOCALIZATION that I had been wanting to
make for a while.
Differential Revision: https://reviews.llvm.org/D94921
GitOrigin-RevId: 933518fff82c8f39626bbcca81adc516483a9651
diff --git a/include/__config_site.in b/include/__config_site.in
index 6089fb7..ec4d410 100644
--- a/include/__config_site.in
+++ b/include/__config_site.in
@@ -30,6 +30,7 @@
#cmakedefine _LIBCPP_NO_VCRUNTIME
#cmakedefine _LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION @_LIBCPP_TYPEINFO_COMPARISON_IMPLEMENTATION@
#cmakedefine _LIBCPP_ABI_NAMESPACE @_LIBCPP_ABI_NAMESPACE@
+#cmakedefine _LIBCPP_HAS_NO_FILESYSTEM_LIBRARY
#cmakedefine _LIBCPP_HAS_PARALLEL_ALGORITHMS
#cmakedefine _LIBCPP_HAS_NO_RANDOM_DEVICE
#cmakedefine _LIBCPP_HAS_NO_LOCALIZATION
diff --git a/include/filesystem b/include/filesystem
index c60020a..92e37e1 100644
--- a/include/filesystem
+++ b/include/filesystem
@@ -251,6 +251,10 @@
#include <__debug>
+#if defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
+# error "The Filesystem library is not supported by this configuration of libc++"
+#endif
+
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
#endif
diff --git a/include/fstream b/include/fstream
index 701f65b..d7d6b46 100644
--- a/include/fstream
+++ b/include/fstream
@@ -186,7 +186,10 @@
#include <__locale>
#include <cstdio>
#include <cstdlib>
-#include <filesystem>
+
+#if !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
+# include <filesystem>
+#endif
#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
#pragma GCC system_header
@@ -235,7 +238,7 @@
_LIBCPP_INLINE_VISIBILITY
basic_filebuf* open(const string& __s, ios_base::openmode __mode);
-#if _LIBCPP_STD_VER >= 17
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
_LIBCPP_AVAILABILITY_FILESYSTEM _LIBCPP_INLINE_VISIBILITY
basic_filebuf* open(const _VSTD_FS::path& __p, ios_base::openmode __mode) {
return open(__p.c_str(), __mode);
@@ -1151,7 +1154,7 @@
#endif
_LIBCPP_INLINE_VISIBILITY
explicit basic_ifstream(const string& __s, ios_base::openmode __mode = ios_base::in);
-#if _LIBCPP_STD_VER >= 17
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
_LIBCPP_AVAILABILITY_FILESYSTEM _LIBCPP_INLINE_VISIBILITY
explicit basic_ifstream(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in)
: basic_ifstream(__p.c_str(), __mode) {}
@@ -1177,7 +1180,7 @@
void open(const wchar_t* __s, ios_base::openmode __mode = ios_base::in);
#endif
void open(const string& __s, ios_base::openmode __mode = ios_base::in);
-#if _LIBCPP_STD_VER >= 17
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
_LIBCPP_AVAILABILITY_FILESYSTEM _LIBCPP_INLINE_VISIBILITY
void open(const filesystem::path& __p,
ios_base::openmode __mode = ios_base::in) {
@@ -1365,7 +1368,7 @@
_LIBCPP_INLINE_VISIBILITY
explicit basic_ofstream(const string& __s, ios_base::openmode __mode = ios_base::out);
-#if _LIBCPP_STD_VER >= 17
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
_LIBCPP_AVAILABILITY_FILESYSTEM _LIBCPP_INLINE_VISIBILITY
explicit basic_ofstream(const filesystem::path& __p, ios_base::openmode __mode = ios_base::out)
: basic_ofstream(__p.c_str(), __mode) {}
@@ -1392,7 +1395,7 @@
#endif
void open(const string& __s, ios_base::openmode __mode = ios_base::out);
-#if _LIBCPP_STD_VER >= 17
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
_LIBCPP_AVAILABILITY_FILESYSTEM _LIBCPP_INLINE_VISIBILITY
void open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::out)
{ return open(__p.c_str(), __mode); }
@@ -1579,7 +1582,7 @@
_LIBCPP_INLINE_VISIBILITY
explicit basic_fstream(const string& __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
-#if _LIBCPP_STD_VER >= 17
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
_LIBCPP_AVAILABILITY_FILESYSTEM _LIBCPP_INLINE_VISIBILITY
explicit basic_fstream(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in | ios_base::out)
: basic_fstream(__p.c_str(), __mode) {}
@@ -1607,7 +1610,7 @@
#endif
void open(const string& __s, ios_base::openmode __mode = ios_base::in | ios_base::out);
-#if _LIBCPP_STD_VER >= 17
+#if _LIBCPP_STD_VER >= 17 && !defined(_LIBCPP_HAS_NO_FILESYSTEM_LIBRARY)
_LIBCPP_AVAILABILITY_FILESYSTEM _LIBCPP_INLINE_VISIBILITY
void open(const filesystem::path& __p, ios_base::openmode __mode = ios_base::in|ios_base::out)
{ return open(__p.c_str(), __mode); }