1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
|
//===--- FS.cpp - File system related utils ----------------------*- C++-*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#include "FS.h"
#include "clang/Basic/LLVM.h"
#include "llvm/ADT/None.h"
#include "llvm/Support/Path.h"
namespace clang {
namespace clangd {
PreambleFileStatusCache::PreambleFileStatusCache(llvm::StringRef MainFilePath)
: MainFilePath(MainFilePath) {
assert(llvm::sys::path::is_absolute(MainFilePath));
}
void PreambleFileStatusCache::update(const llvm::vfs::FileSystem &FS,
llvm::vfs::Status S) {
llvm::SmallString<32> PathStore(S.getName());
if (FS.makeAbsolute(PathStore))
return;
// Do not cache status for the main file.
if (PathStore == MainFilePath)
return;
// Stores the latest status in cache as it can change in a preamble build.
StatCache.insert({PathStore, std::move(S)});
}
llvm::Optional<llvm::vfs::Status>
PreambleFileStatusCache::lookup(llvm::StringRef File) const {
auto I = StatCache.find(File);
if (I != StatCache.end())
return I->getValue();
return None;
}
llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>
PreambleFileStatusCache::getProducingFS(
llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS) {
// This invalidates old status in cache if files are re-`open()`ed or
// re-`stat()`ed in case file status has changed during preamble build.
class CollectFS : public llvm::vfs::ProxyFileSystem {
public:
CollectFS(llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS,
PreambleFileStatusCache &StatCache)
: ProxyFileSystem(std::move(FS)), StatCache(StatCache) {}
llvm::ErrorOr<std::unique_ptr<llvm::vfs::File>>
openFileForRead(const llvm::Twine &Path) override {
auto File = getUnderlyingFS().openFileForRead(Path);
if (!File || !*File)
return File;
// Eagerly stat opened file, as the followup `status` call on the file
// doesn't necessarily go through this FS. This puts some extra work on
// preamble build, but it should be worth it as preamble can be reused
// many times (e.g. code completion) and the repeated status call is
// likely to be cached in the underlying file system anyway.
if (auto S = File->get()->status())
StatCache.update(getUnderlyingFS(), std::move(*S));
return File;
}
llvm::ErrorOr<llvm::vfs::Status> status(const llvm::Twine &Path) override {
auto S = getUnderlyingFS().status(Path);
if (S)
StatCache.update(getUnderlyingFS(), *S);
return S;
}
private:
PreambleFileStatusCache &StatCache;
};
return llvm::IntrusiveRefCntPtr<CollectFS>(
new CollectFS(std::move(FS), *this));
}
llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem>
PreambleFileStatusCache::getConsumingFS(
llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS) const {
class CacheVFS : public llvm::vfs::ProxyFileSystem {
public:
CacheVFS(llvm::IntrusiveRefCntPtr<llvm::vfs::FileSystem> FS,
const PreambleFileStatusCache &StatCache)
: ProxyFileSystem(std::move(FS)), StatCache(StatCache) {}
llvm::ErrorOr<llvm::vfs::Status> status(const llvm::Twine &Path) override {
if (auto S = StatCache.lookup(Path.str()))
return *S;
return getUnderlyingFS().status(Path);
}
private:
const PreambleFileStatusCache &StatCache;
};
return llvm::IntrusiveRefCntPtr<CacheVFS>(new CacheVFS(std::move(FS), *this));
}
} // namespace clangd
} // namespace clang
|
