1 //===- GraphWriter.cpp - Implements GraphWriter support routines ----------===//
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 file implements misc. GraphWriter support routines.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/Support/GraphWriter.h"
14 
15 #include "DebugOptions.h"
16 
17 #include "llvm/ADT/SmallString.h"
18 #include "llvm/ADT/SmallVector.h"
19 #include "llvm/ADT/StringRef.h"
20 #include "llvm/Config/config.h"
21 #include "llvm/Support/Compiler.h"
22 #include "llvm/Support/ErrorHandling.h"
23 #include "llvm/Support/ErrorOr.h"
24 #include "llvm/Support/FileSystem.h"
25 #include "llvm/Support/Path.h"
26 #include "llvm/Support/Program.h"
27 #include "llvm/Support/raw_ostream.h"
28 
29 #ifdef __APPLE__
30 #include "llvm/Support/CommandLine.h"
31 #endif
32 
33 #include <string>
34 #include <system_error>
35 #include <vector>
36 
37 using namespace llvm;
38 
39 #ifdef __APPLE__
40 namespace {
41 struct CreateViewBackground {
42   static void *call() {
43     return new cl::opt<bool>("view-background", cl::Hidden,
44                              cl::desc("Execute graph viewer in the background. "
45                                       "Creates tmp file litter."));
46   }
47 };
48 } // namespace
49 static ManagedStatic<cl::opt<bool>, CreateViewBackground> ViewBackground;
50 void llvm::initGraphWriterOptions() { *ViewBackground; }
51 #else
52 void llvm::initGraphWriterOptions() {}
53 #endif
54 
55 std::string llvm::DOT::EscapeString(const std::string &Label) {
56   std::string Str(Label);
57   for (unsigned i = 0; i != Str.length(); ++i)
58   switch (Str[i]) {
59     case '\n':
60       Str.insert(Str.begin()+i, '\\');  // Escape character...
61       ++i;
62       Str[i] = 'n';
63       break;
64     case '\t':
65       Str.insert(Str.begin()+i, ' ');  // Convert to two spaces
66       ++i;
67       Str[i] = ' ';
68       break;
69     case '\\':
70       if (i+1 != Str.length())
71         switch (Str[i+1]) {
72           case 'l': continue; // don't disturb \l
73           case '|': case '{': case '}':
74             Str.erase(Str.begin()+i); continue;
75           default: break;
76         }
77       [[fallthrough]];
78     case '{': case '}':
79     case '<': case '>':
80     case '|': case '"':
81       Str.insert(Str.begin()+i, '\\');  // Escape character...
82       ++i;  // don't infinite loop
83       break;
84   }
85   return Str;
86 }
87 
88 /// Get a color string for this node number. Simply round-robin selects
89 /// from a reasonable number of colors.
90 StringRef llvm::DOT::getColorString(unsigned ColorNumber) {
91   static const int NumColors = 20;
92   static const char* Colors[NumColors] = {
93     "aaaaaa", "aa0000", "00aa00", "aa5500", "0055ff", "aa00aa", "00aaaa",
94     "555555", "ff5555", "55ff55", "ffff55", "5555ff", "ff55ff", "55ffff",
95     "ffaaaa", "aaffaa", "ffffaa", "aaaaff", "ffaaff", "aaffff"};
96   return Colors[ColorNumber % NumColors];
97 }
98 
99 static std::string replaceIllegalFilenameChars(std::string Filename,
100                                                const char ReplacementChar) {
101   std::string IllegalChars =
102       is_style_windows(sys::path::Style::native) ? "\\/:?\"<>|" : "/";
103 
104   for (char IllegalChar : IllegalChars) {
105     std::replace(Filename.begin(), Filename.end(), IllegalChar,
106                  ReplacementChar);
107   }
108 
109   return Filename;
110 }
111 
112 std::string llvm::createGraphFilename(const Twine &Name, int &FD) {
113   FD = -1;
114   SmallString<128> Filename;
115 
116   // Windows can't always handle long paths, so limit the length of the name.
117   std::string N = Name.str();
118   N = N.substr(0, std::min<std::size_t>(N.size(), 140));
119 
120   // Replace illegal characters in graph Filename with '_' if needed
121   std::string CleansedName = replaceIllegalFilenameChars(N, '_');
122 
123   std::error_code EC =
124       sys::fs::createTemporaryFile(CleansedName, "dot", FD, Filename);
125   if (EC) {
126     errs() << "Error: " << EC.message() << "\n";
127     return "";
128   }
129 
130   errs() << "Writing '" << Filename << "'... ";
131   return std::string(Filename.str());
132 }
133 
134 // Execute the graph viewer. Return true if there were errors.
135 static bool ExecGraphViewer(StringRef ExecPath, std::vector<StringRef> &args,
136                             StringRef Filename, bool wait,
137                             std::string &ErrMsg) {
138   if (wait) {
139     if (sys::ExecuteAndWait(ExecPath, args, std::nullopt, {}, 0, 0, &ErrMsg)) {
140       errs() << "Error: " << ErrMsg << "\n";
141       return true;
142     }
143     sys::fs::remove(Filename);
144     errs() << " done. \n";
145   } else {
146     sys::ExecuteNoWait(ExecPath, args, std::nullopt, {}, 0, &ErrMsg);
147     errs() << "Remember to erase graph file: " << Filename << "\n";
148   }
149   return false;
150 }
151 
152 namespace {
153 
154 struct GraphSession {
155   std::string LogBuffer;
156 
157   bool TryFindProgram(StringRef Names, std::string &ProgramPath) {
158     raw_string_ostream Log(LogBuffer);
159     SmallVector<StringRef, 8> parts;
160     Names.split(parts, '|');
161     for (auto Name : parts) {
162       if (ErrorOr<std::string> P = sys::findProgramByName(Name)) {
163         ProgramPath = *P;
164         return true;
165       }
166       Log << "  Tried '" << Name << "'\n";
167     }
168     return false;
169   }
170 };
171 
172 } // end anonymous namespace
173 
174 static const char *getProgramName(GraphProgram::Name program) {
175   switch (program) {
176   case GraphProgram::DOT:
177     return "dot";
178   case GraphProgram::FDP:
179     return "fdp";
180   case GraphProgram::NEATO:
181     return "neato";
182   case GraphProgram::TWOPI:
183     return "twopi";
184   case GraphProgram::CIRCO:
185     return "circo";
186   }
187   llvm_unreachable("bad kind");
188 }
189 
190 bool llvm::DisplayGraph(StringRef FilenameRef, bool wait,
191                         GraphProgram::Name program) {
192   std::string Filename = std::string(FilenameRef);
193   std::string ErrMsg;
194   std::string ViewerPath;
195   GraphSession S;
196 
197 #ifdef __APPLE__
198   wait &= !*ViewBackground;
199   if (S.TryFindProgram("open", ViewerPath)) {
200     std::vector<StringRef> args;
201     args.push_back(ViewerPath);
202     if (wait)
203       args.push_back("-W");
204     args.push_back(Filename);
205     errs() << "Trying 'open' program... ";
206     if (!ExecGraphViewer(ViewerPath, args, Filename, wait, ErrMsg))
207       return false;
208   }
209 #endif
210   if (S.TryFindProgram("xdg-open", ViewerPath)) {
211     std::vector<StringRef> args;
212     args.push_back(ViewerPath);
213     args.push_back(Filename);
214     errs() << "Trying 'xdg-open' program... ";
215     if (!ExecGraphViewer(ViewerPath, args, Filename, wait, ErrMsg))
216       return false;
217   }
218 
219   // Graphviz
220   if (S.TryFindProgram("Graphviz", ViewerPath)) {
221     std::vector<StringRef> args;
222     args.push_back(ViewerPath);
223     args.push_back(Filename);
224 
225     errs() << "Running 'Graphviz' program... ";
226     return ExecGraphViewer(ViewerPath, args, Filename, wait, ErrMsg);
227   }
228 
229   // xdot
230   if (S.TryFindProgram("xdot|xdot.py", ViewerPath)) {
231     std::vector<StringRef> args;
232     args.push_back(ViewerPath);
233     args.push_back(Filename);
234 
235     args.push_back("-f");
236     args.push_back(getProgramName(program));
237 
238     errs() << "Running 'xdot.py' program... ";
239     return ExecGraphViewer(ViewerPath, args, Filename, wait, ErrMsg);
240   }
241 
242   enum ViewerKind {
243     VK_None,
244     VK_OSXOpen,
245     VK_XDGOpen,
246     VK_Ghostview,
247     VK_CmdStart
248   };
249   ViewerKind Viewer = VK_None;
250 #ifdef __APPLE__
251   if (!Viewer && S.TryFindProgram("open", ViewerPath))
252     Viewer = VK_OSXOpen;
253 #endif
254   if (!Viewer && S.TryFindProgram("gv", ViewerPath))
255     Viewer = VK_Ghostview;
256   if (!Viewer && S.TryFindProgram("xdg-open", ViewerPath))
257     Viewer = VK_XDGOpen;
258 #ifdef _WIN32
259   if (!Viewer && S.TryFindProgram("cmd", ViewerPath)) {
260     Viewer = VK_CmdStart;
261   }
262 #endif
263 
264   // PostScript or PDF graph generator + PostScript/PDF viewer
265   std::string GeneratorPath;
266   if (Viewer &&
267       (S.TryFindProgram(getProgramName(program), GeneratorPath) ||
268        S.TryFindProgram("dot|fdp|neato|twopi|circo", GeneratorPath))) {
269     std::string OutputFilename =
270         Filename + (Viewer == VK_CmdStart ? ".pdf" : ".ps");
271 
272     std::vector<StringRef> args;
273     args.push_back(GeneratorPath);
274     if (Viewer == VK_CmdStart)
275       args.push_back("-Tpdf");
276     else
277       args.push_back("-Tps");
278     args.push_back("-Nfontname=Courier");
279     args.push_back("-Gsize=7.5,10");
280     args.push_back(Filename);
281     args.push_back("-o");
282     args.push_back(OutputFilename);
283 
284     errs() << "Running '" << GeneratorPath << "' program... ";
285 
286     if (ExecGraphViewer(GeneratorPath, args, Filename, true, ErrMsg))
287       return true;
288 
289     // The lifetime of StartArg must include the call of ExecGraphViewer
290     // because the args are passed as vector of char*.
291     std::string StartArg;
292 
293     args.clear();
294     args.push_back(ViewerPath);
295     switch (Viewer) {
296     case VK_OSXOpen:
297       args.push_back("-W");
298       args.push_back(OutputFilename);
299       break;
300     case VK_XDGOpen:
301       wait = false;
302       args.push_back(OutputFilename);
303       break;
304     case VK_Ghostview:
305       args.push_back("--spartan");
306       args.push_back(OutputFilename);
307       break;
308     case VK_CmdStart:
309       args.push_back("/S");
310       args.push_back("/C");
311       StartArg =
312           (StringRef("start ") + (wait ? "/WAIT " : "") + OutputFilename).str();
313       args.push_back(StartArg);
314       break;
315     case VK_None:
316       llvm_unreachable("Invalid viewer");
317     }
318 
319     ErrMsg.clear();
320     return ExecGraphViewer(ViewerPath, args, OutputFilename, wait, ErrMsg);
321   }
322 
323   // dotty
324   if (S.TryFindProgram("dotty", ViewerPath)) {
325     std::vector<StringRef> args;
326     args.push_back(ViewerPath);
327     args.push_back(Filename);
328 
329 // Dotty spawns another app and doesn't wait until it returns
330 #ifdef _WIN32
331     wait = false;
332 #endif
333     errs() << "Running 'dotty' program... ";
334     return ExecGraphViewer(ViewerPath, args, Filename, wait, ErrMsg);
335   }
336 
337   errs() << "Error: Couldn't find a usable graph viewer program:\n";
338   errs() << S.LogBuffer << "\n";
339   return true;
340 }
341