llvm/clang/include/clang/Lex/DependencyDirectivesScanner.h

//===- clang/Lex/DependencyDirectivesScanner.h ---------------------*- C++ -*-//
//
// 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
//
//===----------------------------------------------------------------------===//
///
/// \file
/// This is the interface for scanning header and source files to get the
/// minimum necessary preprocessor directives for evaluating includes. It
/// reduces the source down to #define, #include, #import, @import, and any
/// conditional preprocessor logic that contains one of those.
///
//===----------------------------------------------------------------------===//

#ifndef LLVM_CLANG_LEX_DEPENDENCYDIRECTIVESSCANNER_H
#define LLVM_CLANG_LEX_DEPENDENCYDIRECTIVESSCANNER_H

#include "clang/Basic/SourceLocation.h"
#include "llvm/ADT/ArrayRef.h"

namespace clang {

namespace tok {
enum TokenKind : unsigned short;
}

class DiagnosticsEngine;

namespace dependency_directives_scan {

/// Token lexed as part of dependency directive scanning.
struct Token { … };

/// Represents the kind of preprocessor directive or a module declaration that
/// is tracked by the scanner in its token output.
enum DirectiveKind : uint8_t { … };

/// Represents a directive that's lexed as part of the dependency directives
/// scanning. It's used to track various preprocessor directives that could
/// potentially have an effect on the dependencies.
struct Directive { … };

} // end namespace dependency_directives_scan

/// Scan the input for the preprocessor directives that might have
/// an effect on the dependencies for a compilation unit.
///
/// This function ignores all non-preprocessor code and anything that
/// can't affect what gets included.
///
/// \returns false on success, true on error. If the diagnostic engine is not
/// null, an appropriate error is reported using the given input location
/// with the offset that corresponds to the \p Input buffer offset.
bool scanSourceForDependencyDirectives(
    StringRef Input, SmallVectorImpl<dependency_directives_scan::Token> &Tokens,
    SmallVectorImpl<dependency_directives_scan::Directive> &Directives,
    DiagnosticsEngine *Diags = nullptr,
    SourceLocation InputSourceLoc = SourceLocation());

/// Print the previously scanned dependency directives as minimized source text.
///
/// \param Source The original source text that the dependency directives were
/// scanned from.
/// \param Directives The previously scanned dependency
/// directives.
/// \param OS the stream to print the dependency directives on.
///
/// This is used primarily for testing purposes, during dependency scanning the
/// \p Lexer uses the tokens directly, not their printed version.
void printDependencyDirectivesAsSource(
    StringRef Source,
    ArrayRef<dependency_directives_scan::Directive> Directives,
    llvm::raw_ostream &OS);

} // end namespace clang

#endif // LLVM_CLANG_LEX_DEPENDENCYDIRECTIVESSCANNER_H