1 //===- SourceMgr.cpp - Manager for Simple Source Buffers & Diagnostics ----===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file implements the SourceMgr class. This class is used as a simple
11 // substrate for diagnostics, #include handling, and other low level things for
12 // simple parsers.
13 //
14 //===----------------------------------------------------------------------===//
15
16 #include "llvm/Support/SourceMgr.h"
17 #include "llvm/Support/MemoryBuffer.h"
18 #include "llvm/Support/raw_ostream.h"
19 using namespace llvm;
20
21 namespace {
22 struct LineNoCacheTy {
23 int LastQueryBufferID;
24 const char *LastQuery;
25 unsigned LineNoOfQuery;
26 };
27 }
28
getCache(void * Ptr)29 static LineNoCacheTy *getCache(void *Ptr) {
30 return (LineNoCacheTy*)Ptr;
31 }
32
33
~SourceMgr()34 SourceMgr::~SourceMgr() {
35 // Delete the line # cache if allocated.
36 if (LineNoCacheTy *Cache = getCache(LineNoCache))
37 delete Cache;
38
39 while (!Buffers.empty()) {
40 delete Buffers.back().Buffer;
41 Buffers.pop_back();
42 }
43 }
44
45 /// AddIncludeFile - Search for a file with the specified name in the current
46 /// directory or in one of the IncludeDirs. If no file is found, this returns
47 /// ~0, otherwise it returns the buffer ID of the stacked file.
AddIncludeFile(const std::string & Filename,SMLoc IncludeLoc)48 unsigned SourceMgr::AddIncludeFile(const std::string &Filename,
49 SMLoc IncludeLoc) {
50
51 MemoryBuffer *NewBuf = MemoryBuffer::getFile(Filename.c_str());
52
53 // If the file didn't exist directly, see if it's in an include path.
54 for (unsigned i = 0, e = IncludeDirectories.size(); i != e && !NewBuf; ++i) {
55 std::string IncFile = IncludeDirectories[i] + "/" + Filename;
56 NewBuf = MemoryBuffer::getFile(IncFile.c_str());
57 }
58
59 if (NewBuf == 0) return ~0U;
60
61 return AddNewSourceBuffer(NewBuf, IncludeLoc);
62 }
63
64
65 /// FindBufferContainingLoc - Return the ID of the buffer containing the
66 /// specified location, returning -1 if not found.
FindBufferContainingLoc(SMLoc Loc) const67 int SourceMgr::FindBufferContainingLoc(SMLoc Loc) const {
68 for (unsigned i = 0, e = Buffers.size(); i != e; ++i)
69 if (Loc.getPointer() >= Buffers[i].Buffer->getBufferStart() &&
70 // Use <= here so that a pointer to the null at the end of the buffer
71 // is included as part of the buffer.
72 Loc.getPointer() <= Buffers[i].Buffer->getBufferEnd())
73 return i;
74 return -1;
75 }
76
77 /// FindLineNumber - Find the line number for the specified location in the
78 /// specified file. This is not a fast method.
FindLineNumber(SMLoc Loc,int BufferID) const79 unsigned SourceMgr::FindLineNumber(SMLoc Loc, int BufferID) const {
80 if (BufferID == -1) BufferID = FindBufferContainingLoc(Loc);
81 assert(BufferID != -1 && "Invalid Location!");
82
83 MemoryBuffer *Buff = getBufferInfo(BufferID).Buffer;
84
85 // Count the number of \n's between the start of the file and the specified
86 // location.
87 unsigned LineNo = 1;
88
89 const char *Ptr = Buff->getBufferStart();
90
91 // If we have a line number cache, and if the query is to a later point in the
92 // same file, start searching from the last query location. This optimizes
93 // for the case when multiple diagnostics come out of one file in order.
94 if (LineNoCacheTy *Cache = getCache(LineNoCache))
95 if (Cache->LastQueryBufferID == BufferID &&
96 Cache->LastQuery <= Loc.getPointer()) {
97 Ptr = Cache->LastQuery;
98 LineNo = Cache->LineNoOfQuery;
99 }
100
101 // Scan for the location being queried, keeping track of the number of lines
102 // we see.
103 for (; SMLoc::getFromPointer(Ptr) != Loc; ++Ptr)
104 if (*Ptr == '\n') ++LineNo;
105
106
107 // Allocate the line number cache if it doesn't exist.
108 if (LineNoCache == 0)
109 LineNoCache = new LineNoCacheTy();
110
111 // Update the line # cache.
112 LineNoCacheTy &Cache = *getCache(LineNoCache);
113 Cache.LastQueryBufferID = BufferID;
114 Cache.LastQuery = Ptr;
115 Cache.LineNoOfQuery = LineNo;
116 return LineNo;
117 }
118
PrintIncludeStack(SMLoc IncludeLoc,raw_ostream & OS) const119 void SourceMgr::PrintIncludeStack(SMLoc IncludeLoc, raw_ostream &OS) const {
120 if (IncludeLoc == SMLoc()) return; // Top of stack.
121
122 int CurBuf = FindBufferContainingLoc(IncludeLoc);
123 assert(CurBuf != -1 && "Invalid or unspecified location!");
124
125 PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc, OS);
126
127 OS << "Included from "
128 << getBufferInfo(CurBuf).Buffer->getBufferIdentifier()
129 << ":" << FindLineNumber(IncludeLoc, CurBuf) << ":\n";
130 }
131
132
133 /// GetMessage - Return an SMDiagnostic at the specified location with the
134 /// specified string.
135 ///
136 /// @param Type - If non-null, the kind of message (e.g., "error") which is
137 /// prefixed to the message.
GetMessage(SMLoc Loc,const std::string & Msg,const char * Type,bool ShowLine) const138 SMDiagnostic SourceMgr::GetMessage(SMLoc Loc, const std::string &Msg,
139 const char *Type, bool ShowLine) const {
140
141 // First thing to do: find the current buffer containing the specified
142 // location.
143 int CurBuf = FindBufferContainingLoc(Loc);
144 assert(CurBuf != -1 && "Invalid or unspecified location!");
145
146 MemoryBuffer *CurMB = getBufferInfo(CurBuf).Buffer;
147
148 // Scan backward to find the start of the line.
149 const char *LineStart = Loc.getPointer();
150 while (LineStart != CurMB->getBufferStart() &&
151 LineStart[-1] != '\n' && LineStart[-1] != '\r')
152 --LineStart;
153
154 std::string LineStr;
155 if (ShowLine) {
156 // Get the end of the line.
157 const char *LineEnd = Loc.getPointer();
158 while (LineEnd != CurMB->getBufferEnd() &&
159 LineEnd[0] != '\n' && LineEnd[0] != '\r')
160 ++LineEnd;
161 LineStr = std::string(LineStart, LineEnd);
162 }
163
164 std::string PrintedMsg;
165 if (Type) {
166 PrintedMsg = Type;
167 PrintedMsg += ": ";
168 }
169 PrintedMsg += Msg;
170
171 return SMDiagnostic(*this, Loc,
172 CurMB->getBufferIdentifier(), FindLineNumber(Loc, CurBuf),
173 Loc.getPointer()-LineStart, PrintedMsg,
174 LineStr, ShowLine);
175 }
176
PrintMessage(SMLoc Loc,const std::string & Msg,const char * Type,bool ShowLine) const177 void SourceMgr::PrintMessage(SMLoc Loc, const std::string &Msg,
178 const char *Type, bool ShowLine) const {
179 // Report the message with the diagnostic handler if present.
180 if (DiagHandler) {
181 DiagHandler(GetMessage(Loc, Msg, Type, ShowLine),
182 DiagContext, DiagLocCookie);
183 return;
184 }
185
186 raw_ostream &OS = errs();
187
188 int CurBuf = FindBufferContainingLoc(Loc);
189 assert(CurBuf != -1 && "Invalid or unspecified location!");
190 PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc, OS);
191
192 GetMessage(Loc, Msg, Type, ShowLine).Print(0, OS);
193 }
194
195 //===----------------------------------------------------------------------===//
196 // SMDiagnostic Implementation
197 //===----------------------------------------------------------------------===//
198
Print(const char * ProgName,raw_ostream & S) const199 void SMDiagnostic::Print(const char *ProgName, raw_ostream &S) const {
200 if (ProgName && ProgName[0])
201 S << ProgName << ": ";
202
203 if (!Filename.empty()) {
204 if (Filename == "-")
205 S << "<stdin>";
206 else
207 S << Filename;
208
209 if (LineNo != -1) {
210 S << ':' << LineNo;
211 if (ColumnNo != -1)
212 S << ':' << (ColumnNo+1);
213 }
214 S << ": ";
215 }
216
217 S << Message << '\n';
218
219 if (LineNo != -1 && ColumnNo != -1 && ShowLine) {
220 S << LineContents << '\n';
221
222 // Print out spaces/tabs before the caret.
223 for (unsigned i = 0; i != unsigned(ColumnNo); ++i)
224 S << (LineContents[i] == '\t' ? '\t' : ' ');
225 S << "^\n";
226 }
227 }
228
229
230