llvm-capstone/clang-tools-extra/clangd/ConfigCompile.cpp
Kadir Cetinkaya c9776c8d4e
[clangd] Introduce config compilation for External blocks
Compilation logic for External blocks. A few of the high level points:
- Requires exactly one-of File/Server at a time:
  - Server is ignored in case of both, with a warning.
  - Having none is an error, would render ExternalBlock void.
- Ensures mountpoint is an absolute path:
  - Interprets it as relative to FragmentDirectory.
  - Defaults to FragmentDirectory when empty.
- Marks Background as Skip.

Depends on D90748.

Differential Revision: https://reviews.llvm.org/D90749
2020-11-22 20:59:37 +01:00

432 lines
16 KiB
C++

//===--- ConfigCompile.cpp - Translating Fragments into Config ------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
//
// Fragments are applied to Configs in two steps:
//
// 1. (When the fragment is first loaded)
// FragmentCompiler::compile() traverses the Fragment and creates
// function objects that know how to apply the configuration.
// 2. (Every time a config is required)
// CompiledFragment() executes these functions to populate the Config.
//
// Work could be split between these steps in different ways. We try to
// do as much work as possible in the first step. For example, regexes are
// compiled in stage 1 and captured by the apply function. This is because:
//
// - it's more efficient, as the work done in stage 1 must only be done once
// - problems can be reported in stage 1, in stage 2 we must silently recover
//
//===----------------------------------------------------------------------===//
#include "CompileCommands.h"
#include "Config.h"
#include "ConfigFragment.h"
#include "ConfigProvider.h"
#include "Features.inc"
#include "support/Logger.h"
#include "support/Trace.h"
#include "llvm/ADT/None.h"
#include "llvm/ADT/Optional.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/StringRef.h"
#include "llvm/ADT/StringSwitch.h"
#include "llvm/Support/Error.h"
#include "llvm/Support/FileSystem.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/FormatVariadic.h"
#include "llvm/Support/Path.h"
#include "llvm/Support/Regex.h"
#include "llvm/Support/SMLoc.h"
#include "llvm/Support/SourceMgr.h"
#include <string>
namespace clang {
namespace clangd {
namespace config {
namespace {
// Returns an empty stringref if Path is not under FragmentDir. Returns Path
// as-is when FragmentDir is empty.
llvm::StringRef configRelative(llvm::StringRef Path,
llvm::StringRef FragmentDir) {
if (FragmentDir.empty())
return Path;
if (!Path.consume_front(FragmentDir))
return llvm::StringRef();
return Path.empty() ? "." : Path;
}
struct CompiledFragmentImpl {
// The independent conditions to check before using settings from this config.
// The following fragment has *two* conditions:
// If: { Platform: [mac, linux], PathMatch: foo/.* }
// All of them must be satisfied: the platform and path conditions are ANDed.
// The OR logic for the platform condition is implemented inside the function.
std::vector<llvm::unique_function<bool(const Params &) const>> Conditions;
// Mutations that this fragment will apply to the configuration.
// These are invoked only if the conditions are satisfied.
std::vector<llvm::unique_function<void(const Params &, Config &) const>>
Apply;
bool operator()(const Params &P, Config &C) const {
for (const auto &C : Conditions) {
if (!C(P)) {
dlog("Config fragment {0}: condition not met", this);
return false;
}
}
dlog("Config fragment {0}: applying {1} rules", this, Apply.size());
for (const auto &A : Apply)
A(P, C);
return true;
}
};
// Wrapper around condition compile() functions to reduce arg-passing.
struct FragmentCompiler {
FragmentCompiler(CompiledFragmentImpl &Out, DiagnosticCallback D,
llvm::SourceMgr *SM)
: Out(Out), Diagnostic(D), SourceMgr(SM) {}
CompiledFragmentImpl &Out;
DiagnosticCallback Diagnostic;
llvm::SourceMgr *SourceMgr;
// Normalized Fragment::SourceInfo::Directory.
std::string FragmentDirectory;
llvm::Optional<llvm::Regex> compileRegex(const Located<std::string> &Text) {
std::string Anchored = "^(" + *Text + ")$";
llvm::Regex Result(Anchored);
std::string RegexError;
if (!Result.isValid(RegexError)) {
diag(Error, "Invalid regex " + Anchored + ": " + RegexError, Text.Range);
return llvm::None;
}
return Result;
}
llvm::Optional<std::string> makeAbsolute(Located<std::string> Path,
llvm::StringLiteral Description,
llvm::sys::path::Style Style) {
if (llvm::sys::path::is_absolute(*Path))
return *Path;
if (FragmentDirectory.empty()) {
diag(Error,
llvm::formatv(
"{0} must be an absolute path, because this fragment is not "
"associated with any directory.",
Description)
.str(),
Path.Range);
return llvm::None;
}
llvm::SmallString<256> AbsPath = llvm::StringRef(*Path);
llvm::sys::fs::make_absolute(FragmentDirectory, AbsPath);
llvm::sys::path::native(AbsPath, Style);
return AbsPath.str().str();
}
// Helper with similar API to StringSwitch, for parsing enum values.
template <typename T> class EnumSwitch {
FragmentCompiler &Outer;
llvm::StringRef EnumName;
const Located<std::string> &Input;
llvm::Optional<T> Result;
llvm::SmallVector<llvm::StringLiteral, 8> ValidValues;
public:
EnumSwitch(llvm::StringRef EnumName, const Located<std::string> &In,
FragmentCompiler &Outer)
: Outer(Outer), EnumName(EnumName), Input(In) {}
EnumSwitch &map(llvm::StringLiteral Name, T Value) {
assert(!llvm::is_contained(ValidValues, Name) && "Duplicate value!");
ValidValues.push_back(Name);
if (!Result && *Input == Name)
Result = Value;
return *this;
}
llvm::Optional<T> value() {
if (!Result)
Outer.diag(
Warning,
llvm::formatv("Invalid {0} value '{1}'. Valid values are {2}.",
EnumName, *Input, llvm::join(ValidValues, ", "))
.str(),
Input.Range);
return Result;
};
};
// Attempt to parse a specified string into an enum.
// Yields llvm::None and produces a diagnostic on failure.
//
// Optional<T> Value = compileEnum<En>("Foo", Frag.Foo)
// .map("Foo", Enum::Foo)
// .map("Bar", Enum::Bar)
// .value();
template <typename T>
EnumSwitch<T> compileEnum(llvm::StringRef EnumName,
const Located<std::string> &In) {
return EnumSwitch<T>(EnumName, In, *this);
}
void compile(Fragment &&F) {
if (!F.Source.Directory.empty()) {
FragmentDirectory = llvm::sys::path::convert_to_slash(F.Source.Directory);
if (FragmentDirectory.back() != '/')
FragmentDirectory += '/';
}
compile(std::move(F.If));
compile(std::move(F.CompileFlags));
compile(std::move(F.Index));
compile(std::move(F.ClangTidy));
}
void compile(Fragment::IfBlock &&F) {
if (F.HasUnrecognizedCondition)
Out.Conditions.push_back([&](const Params &) { return false; });
auto PathMatch = std::make_unique<std::vector<llvm::Regex>>();
for (auto &Entry : F.PathMatch) {
if (auto RE = compileRegex(Entry))
PathMatch->push_back(std::move(*RE));
}
if (!PathMatch->empty()) {
Out.Conditions.push_back(
[PathMatch(std::move(PathMatch)),
FragmentDir(FragmentDirectory)](const Params &P) {
if (P.Path.empty())
return false;
llvm::StringRef Path = configRelative(P.Path, FragmentDir);
// Ignore the file if it is not nested under Fragment.
if (Path.empty())
return false;
return llvm::any_of(*PathMatch, [&](const llvm::Regex &RE) {
return RE.match(Path);
});
});
}
auto PathExclude = std::make_unique<std::vector<llvm::Regex>>();
for (auto &Entry : F.PathExclude) {
if (auto RE = compileRegex(Entry))
PathExclude->push_back(std::move(*RE));
}
if (!PathExclude->empty()) {
Out.Conditions.push_back(
[PathExclude(std::move(PathExclude)),
FragmentDir(FragmentDirectory)](const Params &P) {
if (P.Path.empty())
return false;
llvm::StringRef Path = configRelative(P.Path, FragmentDir);
// Ignore the file if it is not nested under Fragment.
if (Path.empty())
return true;
return llvm::none_of(*PathExclude, [&](const llvm::Regex &RE) {
return RE.match(Path);
});
});
}
}
void compile(Fragment::CompileFlagsBlock &&F) {
if (!F.Remove.empty()) {
auto Remove = std::make_shared<ArgStripper>();
for (auto &A : F.Remove)
Remove->strip(*A);
Out.Apply.push_back([Remove(std::shared_ptr<const ArgStripper>(
std::move(Remove)))](const Params &, Config &C) {
C.CompileFlags.Edits.push_back(
[Remove](std::vector<std::string> &Args) {
Remove->process(Args);
});
});
}
if (!F.Add.empty()) {
std::vector<std::string> Add;
for (auto &A : F.Add)
Add.push_back(std::move(*A));
Out.Apply.push_back([Add(std::move(Add))](const Params &, Config &C) {
C.CompileFlags.Edits.push_back([Add](std::vector<std::string> &Args) {
Args.insert(Args.end(), Add.begin(), Add.end());
});
});
}
}
void compile(Fragment::IndexBlock &&F) {
if (F.Background) {
if (auto Val = compileEnum<Config::BackgroundPolicy>("Background",
**F.Background)
.map("Build", Config::BackgroundPolicy::Build)
.map("Skip", Config::BackgroundPolicy::Skip)
.value())
Out.Apply.push_back(
[Val](const Params &, Config &C) { C.Index.Background = *Val; });
}
if (F.External)
compile(std::move(**F.External), F.External->Range);
}
void compile(Fragment::IndexBlock::ExternalBlock &&External,
llvm::SMRange BlockRange) {
#ifndef CLANGD_ENABLE_REMOTE
if (External.Server) {
diag(Error, "Clangd isn't compiled with remote index support, ignoring "
"Server." External.Server->Range);
External.Server.reset();
}
#endif
// Make sure exactly one of the Sources is set.
unsigned SourceCount =
External.File.hasValue() + External.Server.hasValue();
if (SourceCount != 1) {
diag(Error, "Exactly one of File or Server must be set.", BlockRange);
return;
}
Config::ExternalIndexSpec Spec;
if (External.Server) {
Spec.Kind = Config::ExternalIndexSpec::Server;
Spec.Location = std::move(**External.Server);
} else if (External.File) {
Spec.Kind = Config::ExternalIndexSpec::File;
auto AbsPath = makeAbsolute(std::move(*External.File), "File",
llvm::sys::path::Style::native);
if (!AbsPath)
return;
Spec.Location = std::move(*AbsPath);
}
// Make sure MountPoint is an absolute path with forward slashes.
if (!External.MountPoint)
External.MountPoint.emplace(FragmentDirectory);
if ((**External.MountPoint).empty()) {
diag(Error, "A mountpoint is required.", BlockRange);
return;
}
auto AbsPath = makeAbsolute(std::move(*External.MountPoint), "MountPoint",
llvm::sys::path::Style::posix);
if (!AbsPath)
return;
Spec.MountPoint = std::move(*AbsPath);
Out.Apply.push_back([Spec(std::move(Spec))](const Params &P, Config &C) {
if (!P.Path.startswith(Spec.MountPoint))
return;
C.Index.External = Spec;
// Disable background indexing for the files under the mountpoint.
// Note that this will overwrite statements in any previous fragments
// (including the current one).
C.Index.Background = Config::BackgroundPolicy::Skip;
});
}
void compile(Fragment::StyleBlock &&F) {
if (!F.FullyQualifiedNamespaces.empty()) {
std::vector<std::string> FullyQualifiedNamespaces;
for (auto &N : F.FullyQualifiedNamespaces) {
// Normalize the data by dropping both leading and trailing ::
StringRef Namespace(*N);
Namespace.consume_front("::");
Namespace.consume_back("::");
FullyQualifiedNamespaces.push_back(Namespace.str());
}
Out.Apply.push_back([FullyQualifiedNamespaces(
std::move(FullyQualifiedNamespaces))](
const Params &, Config &C) {
C.Style.FullyQualifiedNamespaces.insert(
C.Style.FullyQualifiedNamespaces.begin(),
FullyQualifiedNamespaces.begin(), FullyQualifiedNamespaces.end());
});
}
}
void appendTidyCheckSpec(std::string &CurSpec,
const Located<std::string> &Arg, bool IsPositive) {
StringRef Str = *Arg;
// Don't support negating here, its handled if the item is in the Add or
// Remove list.
if (Str.startswith("-") || Str.contains(',')) {
diag(Error, "Invalid clang-tidy check name", Arg.Range);
return;
}
CurSpec += ',';
if (!IsPositive)
CurSpec += '-';
CurSpec += Str;
}
void compile(Fragment::ClangTidyBlock &&F) {
std::string Checks;
for (auto &CheckGlob : F.Add)
appendTidyCheckSpec(Checks, CheckGlob, true);
for (auto &CheckGlob : F.Remove)
appendTidyCheckSpec(Checks, CheckGlob, false);
if (!Checks.empty())
Out.Apply.push_back(
[Checks = std::move(Checks)](const Params &, Config &C) {
C.ClangTidy.Checks.append(
Checks, C.ClangTidy.Checks.empty() ? /*skip comma*/ 1 : 0,
std::string::npos);
});
if (!F.CheckOptions.empty()) {
std::vector<std::pair<std::string, std::string>> CheckOptions;
for (auto &Opt : F.CheckOptions)
CheckOptions.emplace_back(std::move(*Opt.first),
std::move(*Opt.second));
Out.Apply.push_back(
[CheckOptions = std::move(CheckOptions)](const Params &, Config &C) {
for (auto &StringPair : CheckOptions)
C.ClangTidy.CheckOptions.insert_or_assign(StringPair.first,
StringPair.second);
});
}
}
constexpr static llvm::SourceMgr::DiagKind Error = llvm::SourceMgr::DK_Error;
constexpr static llvm::SourceMgr::DiagKind Warning =
llvm::SourceMgr::DK_Warning;
void diag(llvm::SourceMgr::DiagKind Kind, llvm::StringRef Message,
llvm::SMRange Range) {
if (Range.isValid() && SourceMgr != nullptr)
Diagnostic(SourceMgr->GetMessage(Range.Start, Kind, Message, Range));
else
Diagnostic(llvm::SMDiagnostic("", Kind, Message));
}
};
} // namespace
CompiledFragment Fragment::compile(DiagnosticCallback D) && {
llvm::StringRef ConfigFile = "<unknown>";
std::pair<unsigned, unsigned> LineCol = {0, 0};
if (auto *SM = Source.Manager.get()) {
unsigned BufID = SM->getMainFileID();
LineCol = SM->getLineAndColumn(Source.Location, BufID);
ConfigFile = SM->getBufferInfo(BufID).Buffer->getBufferIdentifier();
}
trace::Span Tracer("ConfigCompile");
SPAN_ATTACH(Tracer, "ConfigFile", ConfigFile);
auto Result = std::make_shared<CompiledFragmentImpl>();
vlog("Config fragment: compiling {0}:{1} -> {2}", ConfigFile, LineCol.first,
Result.get());
FragmentCompiler{*Result, D, Source.Manager.get()}.compile(std::move(*this));
// Return as cheaply-copyable wrapper.
return [Result(std::move(Result))](const Params &P, Config &C) {
return (*Result)(P, C);
};
}
} // namespace config
} // namespace clangd
} // namespace clang