1//===--- TextDiagnosticPrinter.cpp - Diagnostic Printer -------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This diagnostic client prints out their diagnostic messages.
10//
11//===----------------------------------------------------------------------===//
12
13#include "clang/Frontend/TextDiagnosticPrinter.h"
14#include "clang/Basic/DiagnosticOptions.h"
15#include "clang/Basic/SourceManager.h"
16#include "clang/Frontend/TextDiagnostic.h"
17#include "clang/Lex/Lexer.h"
18#include "llvm/Support/ErrorHandling.h"
19#include "llvm/Support/raw_ostream.h"
20using namespace clang;
21
22TextDiagnosticPrinter::TextDiagnosticPrinter(raw_ostream &os,
23 DiagnosticOptions &DiagOpts,
24 bool _OwnsOutputStream)
25 : OS(os), DiagOpts(DiagOpts), OwnsOutputStream(_OwnsOutputStream) {}
26
27TextDiagnosticPrinter::~TextDiagnosticPrinter() {
28 if (OwnsOutputStream)
29 delete &OS;
30}
31
32void TextDiagnosticPrinter::BeginSourceFile(const LangOptions &LO,
33 const Preprocessor *PP) {
34 // Build the TextDiagnostic utility.
35 TextDiag.reset(p: new TextDiagnostic(OS, LO, DiagOpts, PP));
36}
37
38void TextDiagnosticPrinter::EndSourceFile() {
39 TextDiag.reset();
40}
41
42/// Print any diagnostic option information to a raw_ostream.
43///
44/// This implements all of the logic for adding diagnostic options to a message
45/// (via OS). Each relevant option is comma separated and all are enclosed in
46/// the standard bracketing: " [...]".
47static void printDiagnosticOptions(raw_ostream &OS,
48 DiagnosticsEngine::Level Level,
49 const Diagnostic &Info,
50 const DiagnosticOptions &DiagOpts) {
51 bool Started = false;
52 if (DiagOpts.ShowOptionNames) {
53 // Handle special cases for non-warnings early.
54 if (Info.getID() == diag::fatal_too_many_errors) {
55 OS << " [-ferror-limit=]";
56 return;
57 }
58
59 // The code below is somewhat fragile because we are essentially trying to
60 // report to the user what happened by inferring what the diagnostic engine
61 // did. Eventually it might make more sense to have the diagnostic engine
62 // include some "why" information in the diagnostic.
63
64 // If this is a warning which has been mapped to an error by the user (as
65 // inferred by checking whether the default mapping is to an error) then
66 // flag it as such. Note that diagnostics could also have been mapped by a
67 // pragma, but we don't currently have a way to distinguish this.
68 if (Level == DiagnosticsEngine::Error &&
69 Info.getDiags()->getDiagnosticIDs()->isWarningOrExtension(
70 DiagID: Info.getID()) &&
71 !Info.getDiags()->getDiagnosticIDs()->isDefaultMappingAsError(
72 DiagID: Info.getID())) {
73 OS << " [-Werror";
74 Started = true;
75 }
76
77 StringRef Opt =
78 Info.getDiags()->getDiagnosticIDs()->getWarningOptionForDiag(
79 DiagID: Info.getID());
80 if (!Opt.empty()) {
81 OS << (Started ? "," : " [")
82 << (Level == DiagnosticsEngine::Remark ? "-R" : "-W") << Opt;
83 StringRef OptValue = Info.getFlagValue();
84 if (!OptValue.empty())
85 OS << "=" << OptValue;
86 Started = true;
87 }
88 }
89
90 // If the user wants to see category information, include it too.
91 if (DiagOpts.ShowCategories) {
92 unsigned DiagCategory =
93 DiagnosticIDs::getCategoryNumberForDiag(DiagID: Info.getID());
94 if (DiagCategory) {
95 OS << (Started ? "," : " [");
96 Started = true;
97 if (DiagOpts.ShowCategories == 1)
98 OS << DiagCategory;
99 else {
100 assert(DiagOpts.ShowCategories == 2 && "Invalid ShowCategories value");
101 OS << DiagnosticIDs::getCategoryNameFromID(CategoryID: DiagCategory);
102 }
103 }
104 }
105 if (Started)
106 OS << ']';
107}
108
109void TextDiagnosticPrinter::HandleDiagnostic(DiagnosticsEngine::Level Level,
110 const Diagnostic &Info) {
111 // Default implementation (Warnings/errors count).
112 DiagnosticConsumer::HandleDiagnostic(DiagLevel: Level, Info);
113
114 // Render the diagnostic message into a temporary buffer eagerly. We'll use
115 // this later as we print out the diagnostic to the terminal.
116 SmallString<100> OutStr;
117 Info.FormatDiagnostic(OutStr);
118
119 llvm::raw_svector_ostream DiagMessageStream(OutStr);
120 printDiagnosticOptions(OS&: DiagMessageStream, Level, Info, DiagOpts);
121
122 // Keeps track of the starting position of the location
123 // information (e.g., "foo.c:10:4:") that precedes the error
124 // message. We use this information to determine how long the
125 // file+line+column number prefix is.
126 uint64_t StartOfLocationInfo = OS.tell();
127
128 if (!Prefix.empty())
129 OS << Prefix << ": ";
130
131 // Use a dedicated, simpler path for diagnostics without a valid location.
132 // This is important as if the location is missing, we may be emitting
133 // diagnostics in a context that lacks language options, a source manager, or
134 // other infrastructure necessary when emitting more rich diagnostics.
135 if (!Info.getLocation().isValid()) {
136 TextDiagnostic::printDiagnosticLevel(OS, Level, ShowColors: DiagOpts.ShowColors);
137 TextDiagnostic::printDiagnosticMessage(
138 OS, /*IsSupplemental=*/Level == DiagnosticsEngine::Note,
139 Message: DiagMessageStream.str(), CurrentColumn: OS.tell() - StartOfLocationInfo,
140 Columns: DiagOpts.MessageLength, ShowColors: DiagOpts.ShowColors);
141 OS.flush();
142 return;
143 }
144
145 // Assert that the rest of our infrastructure is setup properly.
146 assert(Info.hasSourceManager() &&
147 "Unexpected diagnostic with no source manager");
148 assert(TextDiag && "Unexpected diagnostic outside source file processing");
149
150 TextDiag->emitDiagnostic(
151 Loc: FullSourceLoc(Info.getLocation(), Info.getSourceManager()), Level,
152 Message: DiagMessageStream.str(), Ranges: Info.getRanges(), FixItHints: Info.getFixItHints());
153
154 OS.flush();
155}
156