SourceMgr.cpp revision 2f510aed9cbd24dca1fdc5aabe27325e5ade9e1a 
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"
19using namespace llvm;
20
21SourceMgr::~SourceMgr() {
22  while (!Buffers.empty()) {
23    delete Buffers.back().Buffer;
24    Buffers.pop_back();
25  }
26}
27
28/// AddIncludeFile - Search for a file with the specified name in the current
29/// directory or in one of the IncludeDirs.  If no file is found, this returns
30/// ~0, otherwise it returns the buffer ID of the stacked file.
31unsigned SourceMgr::AddIncludeFile(const std::string &Filename,
32                                   SMLoc IncludeLoc) {
33
34  MemoryBuffer *NewBuf = MemoryBuffer::getFile(Filename.c_str());
35
36  // If the file didn't exist directly, see if it's in an include path.
37  for (unsigned i = 0, e = IncludeDirectories.size(); i != e && !NewBuf; ++i) {
38    std::string IncFile = IncludeDirectories[i] + "/" + Filename;
39    NewBuf = MemoryBuffer::getFile(IncFile.c_str());
40  }
41
42  if (NewBuf == 0) return ~0U;
43
44  return AddNewSourceBuffer(NewBuf, IncludeLoc);
45}
46
47
48/// FindBufferContainingLoc - Return the ID of the buffer containing the
49/// specified location, returning -1 if not found.
50int SourceMgr::FindBufferContainingLoc(SMLoc Loc) const {
51  for (unsigned i = 0, e = Buffers.size(); i != e; ++i)
52    if (Loc.getPointer() >= Buffers[i].Buffer->getBufferStart() &&
53        // Use <= here so that a pointer to the null at the end of the buffer
54        // is included as part of the buffer.
55        Loc.getPointer() <= Buffers[i].Buffer->getBufferEnd())
56      return i;
57  return -1;
58}
59
60/// FindLineNumber - Find the line number for the specified location in the
61/// specified file.  This is not a fast method.
62unsigned SourceMgr::FindLineNumber(SMLoc Loc, int BufferID) const {
63  if (BufferID == -1) BufferID = FindBufferContainingLoc(Loc);
64  assert(BufferID != -1 && "Invalid Location!");
65
66  MemoryBuffer *Buff = getBufferInfo(BufferID).Buffer;
67
68  // Count the number of \n's between the start of the file and the specified
69  // location.
70  unsigned LineNo = 1;
71
72  const char *Ptr = Buff->getBufferStart();
73
74  for (; SMLoc::getFromPointer(Ptr) != Loc; ++Ptr)
75    if (*Ptr == '\n') ++LineNo;
76  return LineNo;
77}
78
79void SourceMgr::PrintIncludeStack(SMLoc IncludeLoc, raw_ostream &OS) const {
80  if (IncludeLoc == SMLoc()) return;  // Top of stack.
81
82  int CurBuf = FindBufferContainingLoc(IncludeLoc);
83  assert(CurBuf != -1 && "Invalid or unspecified location!");
84
85  PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc, OS);
86
87  OS << "Included from "
88     << getBufferInfo(CurBuf).Buffer->getBufferIdentifier()
89     << ":" << FindLineNumber(IncludeLoc, CurBuf) << ":\n";
90}
91
92
93void SourceMgr::PrintMessage(SMLoc Loc, const std::string &Msg,
94                             const char *Type) const {
95  raw_ostream &OS = errs();
96
97  // First thing to do: find the current buffer containing the specified
98  // location.
99  int CurBuf = FindBufferContainingLoc(Loc);
100  assert(CurBuf != -1 && "Invalid or unspecified location!");
101
102  PrintIncludeStack(getBufferInfo(CurBuf).IncludeLoc, OS);
103
104  MemoryBuffer *CurMB = getBufferInfo(CurBuf).Buffer;
105
106
107  // Scan backward to find the start of the line.
108  const char *LineStart = Loc.getPointer();
109  while (LineStart != CurMB->getBufferStart() &&
110         LineStart[-1] != '\n' && LineStart[-1] != '\r')
111    --LineStart;
112  // Get the end of the line.
113  const char *LineEnd = Loc.getPointer();
114  while (LineEnd != CurMB->getBufferEnd() &&
115         LineEnd[0] != '\n' && LineEnd[0] != '\r')
116    ++LineEnd;
117
118  std::string PrintedMsg;
119  if (Type) {
120    PrintedMsg = Type;
121    PrintedMsg += ": ";
122  }
123  PrintedMsg += Msg;
124
125
126  // Print out the line.
127  SMDiagnostic(CurMB->getBufferIdentifier(), FindLineNumber(Loc, CurBuf),
128               Loc.getPointer()-LineStart, PrintedMsg,
129               std::string(LineStart, LineEnd)).Print(0, OS);
130
131}
132
133//===----------------------------------------------------------------------===//
134// SMDiagnostic Implementation
135//===----------------------------------------------------------------------===//
136
137void SMDiagnostic::Print(const char *ProgName, raw_ostream &S) {
138  if (ProgName && ProgName[0])
139    S << ProgName << ": ";
140
141  if (Filename == "-")
142    S << "<stdin>";
143  else
144    S << Filename;
145
146  if (LineNo != -1) {
147    S << ':' << LineNo;
148    if (ColumnNo != -1)
149      S << ':' << (ColumnNo+1);
150  }
151
152  S << ": " << Message << '\n';
153
154  if (LineNo != -1 && ColumnNo != -1) {
155    S << LineContents << '\n';
156
157    // Print out spaces/tabs before the caret.
158    for (unsigned i = 0; i != unsigned(ColumnNo); ++i)
159      S << (LineContents[i] == '\t' ? '\t' : ' ');
160    S << "^\n";
161  }
162}
163
164
165