llvm-project/clang/lib/AST/CommentParser.cpp
Chandler Carruth 2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00

775 lines
23 KiB
C++

//===--- CommentParser.cpp - Doxygen comment parser -----------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//
#include "clang/AST/CommentParser.h"
#include "clang/AST/CommentCommandTraits.h"
#include "clang/AST/CommentDiagnostic.h"
#include "clang/AST/CommentSema.h"
#include "clang/Basic/CharInfo.h"
#include "clang/Basic/SourceManager.h"
#include "llvm/Support/ErrorHandling.h"
namespace clang {
static inline bool isWhitespace(llvm::StringRef S) {
for (StringRef::const_iterator I = S.begin(), E = S.end(); I != E; ++I) {
if (!isWhitespace(*I))
return false;
}
return true;
}
namespace comments {
/// Re-lexes a sequence of tok::text tokens.
class TextTokenRetokenizer {
llvm::BumpPtrAllocator &Allocator;
Parser &P;
/// This flag is set when there are no more tokens we can fetch from lexer.
bool NoMoreInterestingTokens;
/// Token buffer: tokens we have processed and lookahead.
SmallVector<Token, 16> Toks;
/// A position in \c Toks.
struct Position {
const char *BufferStart;
const char *BufferEnd;
const char *BufferPtr;
SourceLocation BufferStartLoc;
unsigned CurToken;
};
/// Current position in Toks.
Position Pos;
bool isEnd() const {
return Pos.CurToken >= Toks.size();
}
/// Sets up the buffer pointers to point to current token.
void setupBuffer() {
assert(!isEnd());
const Token &Tok = Toks[Pos.CurToken];
Pos.BufferStart = Tok.getText().begin();
Pos.BufferEnd = Tok.getText().end();
Pos.BufferPtr = Pos.BufferStart;
Pos.BufferStartLoc = Tok.getLocation();
}
SourceLocation getSourceLocation() const {
const unsigned CharNo = Pos.BufferPtr - Pos.BufferStart;
return Pos.BufferStartLoc.getLocWithOffset(CharNo);
}
char peek() const {
assert(!isEnd());
assert(Pos.BufferPtr != Pos.BufferEnd);
return *Pos.BufferPtr;
}
void consumeChar() {
assert(!isEnd());
assert(Pos.BufferPtr != Pos.BufferEnd);
Pos.BufferPtr++;
if (Pos.BufferPtr == Pos.BufferEnd) {
Pos.CurToken++;
if (isEnd() && !addToken())
return;
assert(!isEnd());
setupBuffer();
}
}
/// Add a token.
/// Returns true on success, false if there are no interesting tokens to
/// fetch from lexer.
bool addToken() {
if (NoMoreInterestingTokens)
return false;
if (P.Tok.is(tok::newline)) {
// If we see a single newline token between text tokens, skip it.
Token Newline = P.Tok;
P.consumeToken();
if (P.Tok.isNot(tok::text)) {
P.putBack(Newline);
NoMoreInterestingTokens = true;
return false;
}
}
if (P.Tok.isNot(tok::text)) {
NoMoreInterestingTokens = true;
return false;
}
Toks.push_back(P.Tok);
P.consumeToken();
if (Toks.size() == 1)
setupBuffer();
return true;
}
void consumeWhitespace() {
while (!isEnd()) {
if (isWhitespace(peek()))
consumeChar();
else
break;
}
}
void formTokenWithChars(Token &Result,
SourceLocation Loc,
const char *TokBegin,
unsigned TokLength,
StringRef Text) {
Result.setLocation(Loc);
Result.setKind(tok::text);
Result.setLength(TokLength);
#ifndef NDEBUG
Result.TextPtr = "<UNSET>";
Result.IntVal = 7;
#endif
Result.setText(Text);
}
public:
TextTokenRetokenizer(llvm::BumpPtrAllocator &Allocator, Parser &P):
Allocator(Allocator), P(P), NoMoreInterestingTokens(false) {
Pos.CurToken = 0;
addToken();
}
/// Extract a word -- sequence of non-whitespace characters.
bool lexWord(Token &Tok) {
if (isEnd())
return false;
Position SavedPos = Pos;
consumeWhitespace();
SmallString<32> WordText;
const char *WordBegin = Pos.BufferPtr;
SourceLocation Loc = getSourceLocation();
while (!isEnd()) {
const char C = peek();
if (!isWhitespace(C)) {
WordText.push_back(C);
consumeChar();
} else
break;
}
const unsigned Length = WordText.size();
if (Length == 0) {
Pos = SavedPos;
return false;
}
char *TextPtr = Allocator.Allocate<char>(Length + 1);
memcpy(TextPtr, WordText.c_str(), Length + 1);
StringRef Text = StringRef(TextPtr, Length);
formTokenWithChars(Tok, Loc, WordBegin, Length, Text);
return true;
}
bool lexDelimitedSeq(Token &Tok, char OpenDelim, char CloseDelim) {
if (isEnd())
return false;
Position SavedPos = Pos;
consumeWhitespace();
SmallString<32> WordText;
const char *WordBegin = Pos.BufferPtr;
SourceLocation Loc = getSourceLocation();
bool Error = false;
if (!isEnd()) {
const char C = peek();
if (C == OpenDelim) {
WordText.push_back(C);
consumeChar();
} else
Error = true;
}
char C = '\0';
while (!Error && !isEnd()) {
C = peek();
WordText.push_back(C);
consumeChar();
if (C == CloseDelim)
break;
}
if (!Error && C != CloseDelim)
Error = true;
if (Error) {
Pos = SavedPos;
return false;
}
const unsigned Length = WordText.size();
char *TextPtr = Allocator.Allocate<char>(Length + 1);
memcpy(TextPtr, WordText.c_str(), Length + 1);
StringRef Text = StringRef(TextPtr, Length);
formTokenWithChars(Tok, Loc, WordBegin,
Pos.BufferPtr - WordBegin, Text);
return true;
}
/// Put back tokens that we didn't consume.
void putBackLeftoverTokens() {
if (isEnd())
return;
bool HavePartialTok = false;
Token PartialTok;
if (Pos.BufferPtr != Pos.BufferStart) {
formTokenWithChars(PartialTok, getSourceLocation(),
Pos.BufferPtr, Pos.BufferEnd - Pos.BufferPtr,
StringRef(Pos.BufferPtr,
Pos.BufferEnd - Pos.BufferPtr));
HavePartialTok = true;
Pos.CurToken++;
}
P.putBack(llvm::makeArrayRef(Toks.begin() + Pos.CurToken, Toks.end()));
Pos.CurToken = Toks.size();
if (HavePartialTok)
P.putBack(PartialTok);
}
};
Parser::Parser(Lexer &L, Sema &S, llvm::BumpPtrAllocator &Allocator,
const SourceManager &SourceMgr, DiagnosticsEngine &Diags,
const CommandTraits &Traits):
L(L), S(S), Allocator(Allocator), SourceMgr(SourceMgr), Diags(Diags),
Traits(Traits) {
consumeToken();
}
void Parser::parseParamCommandArgs(ParamCommandComment *PC,
TextTokenRetokenizer &Retokenizer) {
Token Arg;
// Check if argument looks like direction specification: [dir]
// e.g., [in], [out], [in,out]
if (Retokenizer.lexDelimitedSeq(Arg, '[', ']'))
S.actOnParamCommandDirectionArg(PC,
Arg.getLocation(),
Arg.getEndLocation(),
Arg.getText());
if (Retokenizer.lexWord(Arg))
S.actOnParamCommandParamNameArg(PC,
Arg.getLocation(),
Arg.getEndLocation(),
Arg.getText());
}
void Parser::parseTParamCommandArgs(TParamCommandComment *TPC,
TextTokenRetokenizer &Retokenizer) {
Token Arg;
if (Retokenizer.lexWord(Arg))
S.actOnTParamCommandParamNameArg(TPC,
Arg.getLocation(),
Arg.getEndLocation(),
Arg.getText());
}
void Parser::parseBlockCommandArgs(BlockCommandComment *BC,
TextTokenRetokenizer &Retokenizer,
unsigned NumArgs) {
typedef BlockCommandComment::Argument Argument;
Argument *Args =
new (Allocator.Allocate<Argument>(NumArgs)) Argument[NumArgs];
unsigned ParsedArgs = 0;
Token Arg;
while (ParsedArgs < NumArgs && Retokenizer.lexWord(Arg)) {
Args[ParsedArgs] = Argument(SourceRange(Arg.getLocation(),
Arg.getEndLocation()),
Arg.getText());
ParsedArgs++;
}
S.actOnBlockCommandArgs(BC, llvm::makeArrayRef(Args, ParsedArgs));
}
BlockCommandComment *Parser::parseBlockCommand() {
assert(Tok.is(tok::backslash_command) || Tok.is(tok::at_command));
ParamCommandComment *PC = nullptr;
TParamCommandComment *TPC = nullptr;
BlockCommandComment *BC = nullptr;
const CommandInfo *Info = Traits.getCommandInfo(Tok.getCommandID());
CommandMarkerKind CommandMarker =
Tok.is(tok::backslash_command) ? CMK_Backslash : CMK_At;
if (Info->IsParamCommand) {
PC = S.actOnParamCommandStart(Tok.getLocation(),
Tok.getEndLocation(),
Tok.getCommandID(),
CommandMarker);
} else if (Info->IsTParamCommand) {
TPC = S.actOnTParamCommandStart(Tok.getLocation(),
Tok.getEndLocation(),
Tok.getCommandID(),
CommandMarker);
} else {
BC = S.actOnBlockCommandStart(Tok.getLocation(),
Tok.getEndLocation(),
Tok.getCommandID(),
CommandMarker);
}
consumeToken();
if (isTokBlockCommand()) {
// Block command ahead. We can't nest block commands, so pretend that this
// command has an empty argument.
ParagraphComment *Paragraph = S.actOnParagraphComment(None);
if (PC) {
S.actOnParamCommandFinish(PC, Paragraph);
return PC;
} else if (TPC) {
S.actOnTParamCommandFinish(TPC, Paragraph);
return TPC;
} else {
S.actOnBlockCommandFinish(BC, Paragraph);
return BC;
}
}
if (PC || TPC || Info->NumArgs > 0) {
// In order to parse command arguments we need to retokenize a few
// following text tokens.
TextTokenRetokenizer Retokenizer(Allocator, *this);
if (PC)
parseParamCommandArgs(PC, Retokenizer);
else if (TPC)
parseTParamCommandArgs(TPC, Retokenizer);
else
parseBlockCommandArgs(BC, Retokenizer, Info->NumArgs);
Retokenizer.putBackLeftoverTokens();
}
// If there's a block command ahead, we will attach an empty paragraph to
// this command.
bool EmptyParagraph = false;
if (isTokBlockCommand())
EmptyParagraph = true;
else if (Tok.is(tok::newline)) {
Token PrevTok = Tok;
consumeToken();
EmptyParagraph = isTokBlockCommand();
putBack(PrevTok);
}
ParagraphComment *Paragraph;
if (EmptyParagraph)
Paragraph = S.actOnParagraphComment(None);
else {
BlockContentComment *Block = parseParagraphOrBlockCommand();
// Since we have checked for a block command, we should have parsed a
// paragraph.
Paragraph = cast<ParagraphComment>(Block);
}
if (PC) {
S.actOnParamCommandFinish(PC, Paragraph);
return PC;
} else if (TPC) {
S.actOnTParamCommandFinish(TPC, Paragraph);
return TPC;
} else {
S.actOnBlockCommandFinish(BC, Paragraph);
return BC;
}
}
InlineCommandComment *Parser::parseInlineCommand() {
assert(Tok.is(tok::backslash_command) || Tok.is(tok::at_command));
const Token CommandTok = Tok;
consumeToken();
TextTokenRetokenizer Retokenizer(Allocator, *this);
Token ArgTok;
bool ArgTokValid = Retokenizer.lexWord(ArgTok);
InlineCommandComment *IC;
if (ArgTokValid) {
IC = S.actOnInlineCommand(CommandTok.getLocation(),
CommandTok.getEndLocation(),
CommandTok.getCommandID(),
ArgTok.getLocation(),
ArgTok.getEndLocation(),
ArgTok.getText());
} else {
IC = S.actOnInlineCommand(CommandTok.getLocation(),
CommandTok.getEndLocation(),
CommandTok.getCommandID());
}
Retokenizer.putBackLeftoverTokens();
return IC;
}
HTMLStartTagComment *Parser::parseHTMLStartTag() {
assert(Tok.is(tok::html_start_tag));
HTMLStartTagComment *HST =
S.actOnHTMLStartTagStart(Tok.getLocation(),
Tok.getHTMLTagStartName());
consumeToken();
SmallVector<HTMLStartTagComment::Attribute, 2> Attrs;
while (true) {
switch (Tok.getKind()) {
case tok::html_ident: {
Token Ident = Tok;
consumeToken();
if (Tok.isNot(tok::html_equals)) {
Attrs.push_back(HTMLStartTagComment::Attribute(Ident.getLocation(),
Ident.getHTMLIdent()));
continue;
}
Token Equals = Tok;
consumeToken();
if (Tok.isNot(tok::html_quoted_string)) {
Diag(Tok.getLocation(),
diag::warn_doc_html_start_tag_expected_quoted_string)
<< SourceRange(Equals.getLocation());
Attrs.push_back(HTMLStartTagComment::Attribute(Ident.getLocation(),
Ident.getHTMLIdent()));
while (Tok.is(tok::html_equals) ||
Tok.is(tok::html_quoted_string))
consumeToken();
continue;
}
Attrs.push_back(HTMLStartTagComment::Attribute(
Ident.getLocation(),
Ident.getHTMLIdent(),
Equals.getLocation(),
SourceRange(Tok.getLocation(),
Tok.getEndLocation()),
Tok.getHTMLQuotedString()));
consumeToken();
continue;
}
case tok::html_greater:
S.actOnHTMLStartTagFinish(HST,
S.copyArray(llvm::makeArrayRef(Attrs)),
Tok.getLocation(),
/* IsSelfClosing = */ false);
consumeToken();
return HST;
case tok::html_slash_greater:
S.actOnHTMLStartTagFinish(HST,
S.copyArray(llvm::makeArrayRef(Attrs)),
Tok.getLocation(),
/* IsSelfClosing = */ true);
consumeToken();
return HST;
case tok::html_equals:
case tok::html_quoted_string:
Diag(Tok.getLocation(),
diag::warn_doc_html_start_tag_expected_ident_or_greater);
while (Tok.is(tok::html_equals) ||
Tok.is(tok::html_quoted_string))
consumeToken();
if (Tok.is(tok::html_ident) ||
Tok.is(tok::html_greater) ||
Tok.is(tok::html_slash_greater))
continue;
S.actOnHTMLStartTagFinish(HST,
S.copyArray(llvm::makeArrayRef(Attrs)),
SourceLocation(),
/* IsSelfClosing = */ false);
return HST;
default:
// Not a token from an HTML start tag. Thus HTML tag prematurely ended.
S.actOnHTMLStartTagFinish(HST,
S.copyArray(llvm::makeArrayRef(Attrs)),
SourceLocation(),
/* IsSelfClosing = */ false);
bool StartLineInvalid;
const unsigned StartLine = SourceMgr.getPresumedLineNumber(
HST->getLocation(),
&StartLineInvalid);
bool EndLineInvalid;
const unsigned EndLine = SourceMgr.getPresumedLineNumber(
Tok.getLocation(),
&EndLineInvalid);
if (StartLineInvalid || EndLineInvalid || StartLine == EndLine)
Diag(Tok.getLocation(),
diag::warn_doc_html_start_tag_expected_ident_or_greater)
<< HST->getSourceRange();
else {
Diag(Tok.getLocation(),
diag::warn_doc_html_start_tag_expected_ident_or_greater);
Diag(HST->getLocation(), diag::note_doc_html_tag_started_here)
<< HST->getSourceRange();
}
return HST;
}
}
}
HTMLEndTagComment *Parser::parseHTMLEndTag() {
assert(Tok.is(tok::html_end_tag));
Token TokEndTag = Tok;
consumeToken();
SourceLocation Loc;
if (Tok.is(tok::html_greater)) {
Loc = Tok.getLocation();
consumeToken();
}
return S.actOnHTMLEndTag(TokEndTag.getLocation(),
Loc,
TokEndTag.getHTMLTagEndName());
}
BlockContentComment *Parser::parseParagraphOrBlockCommand() {
SmallVector<InlineContentComment *, 8> Content;
while (true) {
switch (Tok.getKind()) {
case tok::verbatim_block_begin:
case tok::verbatim_line_name:
case tok::eof:
break; // Block content or EOF ahead, finish this parapgaph.
case tok::unknown_command:
Content.push_back(S.actOnUnknownCommand(Tok.getLocation(),
Tok.getEndLocation(),
Tok.getUnknownCommandName()));
consumeToken();
continue;
case tok::backslash_command:
case tok::at_command: {
const CommandInfo *Info = Traits.getCommandInfo(Tok.getCommandID());
if (Info->IsBlockCommand) {
if (Content.size() == 0)
return parseBlockCommand();
break; // Block command ahead, finish this parapgaph.
}
if (Info->IsVerbatimBlockEndCommand) {
Diag(Tok.getLocation(),
diag::warn_verbatim_block_end_without_start)
<< Tok.is(tok::at_command)
<< Info->Name
<< SourceRange(Tok.getLocation(), Tok.getEndLocation());
consumeToken();
continue;
}
if (Info->IsUnknownCommand) {
Content.push_back(S.actOnUnknownCommand(Tok.getLocation(),
Tok.getEndLocation(),
Info->getID()));
consumeToken();
continue;
}
assert(Info->IsInlineCommand);
Content.push_back(parseInlineCommand());
continue;
}
case tok::newline: {
consumeToken();
if (Tok.is(tok::newline) || Tok.is(tok::eof)) {
consumeToken();
break; // Two newlines -- end of paragraph.
}
// Also allow [tok::newline, tok::text, tok::newline] if the middle
// tok::text is just whitespace.
if (Tok.is(tok::text) && isWhitespace(Tok.getText())) {
Token WhitespaceTok = Tok;
consumeToken();
if (Tok.is(tok::newline) || Tok.is(tok::eof)) {
consumeToken();
break;
}
// We have [tok::newline, tok::text, non-newline]. Put back tok::text.
putBack(WhitespaceTok);
}
if (Content.size() > 0)
Content.back()->addTrailingNewline();
continue;
}
// Don't deal with HTML tag soup now.
case tok::html_start_tag:
Content.push_back(parseHTMLStartTag());
continue;
case tok::html_end_tag:
Content.push_back(parseHTMLEndTag());
continue;
case tok::text:
Content.push_back(S.actOnText(Tok.getLocation(),
Tok.getEndLocation(),
Tok.getText()));
consumeToken();
continue;
case tok::verbatim_block_line:
case tok::verbatim_block_end:
case tok::verbatim_line_text:
case tok::html_ident:
case tok::html_equals:
case tok::html_quoted_string:
case tok::html_greater:
case tok::html_slash_greater:
llvm_unreachable("should not see this token");
}
break;
}
return S.actOnParagraphComment(S.copyArray(llvm::makeArrayRef(Content)));
}
VerbatimBlockComment *Parser::parseVerbatimBlock() {
assert(Tok.is(tok::verbatim_block_begin));
VerbatimBlockComment *VB =
S.actOnVerbatimBlockStart(Tok.getLocation(),
Tok.getVerbatimBlockID());
consumeToken();
// Don't create an empty line if verbatim opening command is followed
// by a newline.
if (Tok.is(tok::newline))
consumeToken();
SmallVector<VerbatimBlockLineComment *, 8> Lines;
while (Tok.is(tok::verbatim_block_line) ||
Tok.is(tok::newline)) {
VerbatimBlockLineComment *Line;
if (Tok.is(tok::verbatim_block_line)) {
Line = S.actOnVerbatimBlockLine(Tok.getLocation(),
Tok.getVerbatimBlockText());
consumeToken();
if (Tok.is(tok::newline)) {
consumeToken();
}
} else {
// Empty line, just a tok::newline.
Line = S.actOnVerbatimBlockLine(Tok.getLocation(), "");
consumeToken();
}
Lines.push_back(Line);
}
if (Tok.is(tok::verbatim_block_end)) {
const CommandInfo *Info = Traits.getCommandInfo(Tok.getVerbatimBlockID());
S.actOnVerbatimBlockFinish(VB, Tok.getLocation(),
Info->Name,
S.copyArray(llvm::makeArrayRef(Lines)));
consumeToken();
} else {
// Unterminated \\verbatim block
S.actOnVerbatimBlockFinish(VB, SourceLocation(), "",
S.copyArray(llvm::makeArrayRef(Lines)));
}
return VB;
}
VerbatimLineComment *Parser::parseVerbatimLine() {
assert(Tok.is(tok::verbatim_line_name));
Token NameTok = Tok;
consumeToken();
SourceLocation TextBegin;
StringRef Text;
// Next token might not be a tok::verbatim_line_text if verbatim line
// starting command comes just before a newline or comment end.
if (Tok.is(tok::verbatim_line_text)) {
TextBegin = Tok.getLocation();
Text = Tok.getVerbatimLineText();
} else {
TextBegin = NameTok.getEndLocation();
Text = "";
}
VerbatimLineComment *VL = S.actOnVerbatimLine(NameTok.getLocation(),
NameTok.getVerbatimLineID(),
TextBegin,
Text);
consumeToken();
return VL;
}
BlockContentComment *Parser::parseBlockContent() {
switch (Tok.getKind()) {
case tok::text:
case tok::unknown_command:
case tok::backslash_command:
case tok::at_command:
case tok::html_start_tag:
case tok::html_end_tag:
return parseParagraphOrBlockCommand();
case tok::verbatim_block_begin:
return parseVerbatimBlock();
case tok::verbatim_line_name:
return parseVerbatimLine();
case tok::eof:
case tok::newline:
case tok::verbatim_block_line:
case tok::verbatim_block_end:
case tok::verbatim_line_text:
case tok::html_ident:
case tok::html_equals:
case tok::html_quoted_string:
case tok::html_greater:
case tok::html_slash_greater:
llvm_unreachable("should not see this token");
}
llvm_unreachable("bogus token kind");
}
FullComment *Parser::parseFullComment() {
// Skip newlines at the beginning of the comment.
while (Tok.is(tok::newline))
consumeToken();
SmallVector<BlockContentComment *, 8> Blocks;
while (Tok.isNot(tok::eof)) {
Blocks.push_back(parseBlockContent());
// Skip extra newlines after paragraph end.
while (Tok.is(tok::newline))
consumeToken();
}
return S.actOnFullComment(S.copyArray(llvm::makeArrayRef(Blocks)));
}
} // end namespace comments
} // end namespace clang