xref: /freebsd/contrib/llvm-project/lldb/source/Core/SourceManager.cpp (revision aa1a8ff2d6dbc51ef058f46f3db5a8bb77967145)
1 //===-- SourceManager.cpp -------------------------------------------------===//
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 #include "lldb/Core/SourceManager.h"
10 
11 #include "lldb/Core/Address.h"
12 #include "lldb/Core/AddressRange.h"
13 #include "lldb/Core/Debugger.h"
14 #include "lldb/Core/FormatEntity.h"
15 #include "lldb/Core/Highlighter.h"
16 #include "lldb/Core/Module.h"
17 #include "lldb/Core/ModuleList.h"
18 #include "lldb/Host/FileSystem.h"
19 #include "lldb/Symbol/CompileUnit.h"
20 #include "lldb/Symbol/Function.h"
21 #include "lldb/Symbol/LineEntry.h"
22 #include "lldb/Symbol/SymbolContext.h"
23 #include "lldb/Target/PathMappingList.h"
24 #include "lldb/Target/Process.h"
25 #include "lldb/Target/Target.h"
26 #include "lldb/Utility/AnsiTerminal.h"
27 #include "lldb/Utility/ConstString.h"
28 #include "lldb/Utility/DataBuffer.h"
29 #include "lldb/Utility/LLDBLog.h"
30 #include "lldb/Utility/Log.h"
31 #include "lldb/Utility/RegularExpression.h"
32 #include "lldb/Utility/Stream.h"
33 #include "lldb/lldb-enumerations.h"
34 
35 #include "llvm/ADT/Twine.h"
36 
37 #include <memory>
38 #include <optional>
39 #include <utility>
40 
41 #include <cassert>
42 #include <cstdio>
43 
44 namespace lldb_private {
45 class ExecutionContext;
46 }
47 namespace lldb_private {
48 class ValueObject;
49 }
50 
51 using namespace lldb;
52 using namespace lldb_private;
53 
54 static inline bool is_newline_char(char ch) { return ch == '\n' || ch == '\r'; }
55 
56 static void resolve_tilde(FileSpec &file_spec) {
57   if (!FileSystem::Instance().Exists(file_spec) &&
58       file_spec.GetDirectory() &&
59       file_spec.GetDirectory().GetCString()[0] == '~') {
60     FileSystem::Instance().Resolve(file_spec);
61   }
62 }
63 
64 // SourceManager constructor
65 SourceManager::SourceManager(const TargetSP &target_sp)
66     : m_last_line(0), m_last_count(0), m_default_set(false),
67       m_target_wp(target_sp),
68       m_debugger_wp(target_sp->GetDebugger().shared_from_this()) {}
69 
70 SourceManager::SourceManager(const DebuggerSP &debugger_sp)
71     : m_last_line(0), m_last_count(0), m_default_set(false), m_target_wp(),
72       m_debugger_wp(debugger_sp) {}
73 
74 // Destructor
75 SourceManager::~SourceManager() = default;
76 
77 SourceManager::FileSP SourceManager::GetFile(const FileSpec &file_spec) {
78   if (!file_spec)
79     return {};
80 
81   Log *log = GetLog(LLDBLog::Source);
82 
83   DebuggerSP debugger_sp(m_debugger_wp.lock());
84   TargetSP target_sp(m_target_wp.lock());
85 
86   if (!debugger_sp || !debugger_sp->GetUseSourceCache()) {
87     LLDB_LOG(log, "Source file caching disabled: creating new source file: {0}",
88              file_spec);
89     if (target_sp)
90       return std::make_shared<File>(file_spec, target_sp);
91     return std::make_shared<File>(file_spec, debugger_sp);
92   }
93 
94   ProcessSP process_sp = target_sp ? target_sp->GetProcessSP() : ProcessSP();
95 
96   // Check the process source cache first. This is the fast path which avoids
97   // touching the file system unless the path remapping has changed.
98   if (process_sp) {
99     if (FileSP file_sp =
100             process_sp->GetSourceFileCache().FindSourceFile(file_spec)) {
101       LLDB_LOG(log, "Found source file in the process cache: {0}", file_spec);
102       if (file_sp->PathRemappingIsStale()) {
103         LLDB_LOG(log, "Path remapping is stale: removing file from caches: {0}",
104                  file_spec);
105 
106         // Remove the file from the debugger and process cache. Otherwise we'll
107         // hit the same issue again below when querying the debugger cache.
108         debugger_sp->GetSourceFileCache().RemoveSourceFile(file_sp);
109         process_sp->GetSourceFileCache().RemoveSourceFile(file_sp);
110 
111         file_sp.reset();
112       } else {
113         return file_sp;
114       }
115     }
116   }
117 
118   // Cache miss in the process cache. Check the debugger source cache.
119   FileSP file_sp = debugger_sp->GetSourceFileCache().FindSourceFile(file_spec);
120 
121   // We found the file in the debugger cache. Check if anything invalidated our
122   // cache result.
123   if (file_sp)
124     LLDB_LOG(log, "Found source file in the debugger cache: {0}", file_spec);
125 
126   // Check if the path remapping has changed.
127   if (file_sp && file_sp->PathRemappingIsStale()) {
128     LLDB_LOG(log, "Path remapping is stale: {0}", file_spec);
129     file_sp.reset();
130   }
131 
132   // Check if the modification time has changed.
133   if (file_sp && file_sp->ModificationTimeIsStale()) {
134     LLDB_LOG(log, "Modification time is stale: {0}", file_spec);
135     file_sp.reset();
136   }
137 
138   // Check if the file exists on disk.
139   if (file_sp && !FileSystem::Instance().Exists(file_sp->GetFileSpec())) {
140     LLDB_LOG(log, "File doesn't exist on disk: {0}", file_spec);
141     file_sp.reset();
142   }
143 
144   // If at this point we don't have a valid file, it means we either didn't find
145   // it in the debugger cache or something caused it to be invalidated.
146   if (!file_sp) {
147     LLDB_LOG(log, "Creating and caching new source file: {0}", file_spec);
148 
149     // (Re)create the file.
150     if (target_sp)
151       file_sp = std::make_shared<File>(file_spec, target_sp);
152     else
153       file_sp = std::make_shared<File>(file_spec, debugger_sp);
154 
155     // Add the file to the debugger and process cache. If the file was
156     // invalidated, this will overwrite it.
157     debugger_sp->GetSourceFileCache().AddSourceFile(file_spec, file_sp);
158     if (process_sp)
159       process_sp->GetSourceFileCache().AddSourceFile(file_spec, file_sp);
160   }
161 
162   return file_sp;
163 }
164 
165 static bool should_highlight_source(DebuggerSP debugger_sp) {
166   if (!debugger_sp)
167     return false;
168 
169   // We don't use ANSI stop column formatting if the debugger doesn't think it
170   // should be using color.
171   if (!debugger_sp->GetUseColor())
172     return false;
173 
174   return debugger_sp->GetHighlightSource();
175 }
176 
177 static bool should_show_stop_column_with_ansi(DebuggerSP debugger_sp) {
178   // We don't use ANSI stop column formatting if we can't lookup values from
179   // the debugger.
180   if (!debugger_sp)
181     return false;
182 
183   // We don't use ANSI stop column formatting if the debugger doesn't think it
184   // should be using color.
185   if (!debugger_sp->GetUseColor())
186     return false;
187 
188   // We only use ANSI stop column formatting if we're either supposed to show
189   // ANSI where available (which we know we have when we get to this point), or
190   // if we're only supposed to use ANSI.
191   const auto value = debugger_sp->GetStopShowColumn();
192   return ((value == eStopShowColumnAnsiOrCaret) ||
193           (value == eStopShowColumnAnsi));
194 }
195 
196 static bool should_show_stop_column_with_caret(DebuggerSP debugger_sp) {
197   // We don't use text-based stop column formatting if we can't lookup values
198   // from the debugger.
199   if (!debugger_sp)
200     return false;
201 
202   // If we're asked to show the first available of ANSI or caret, then we do
203   // show the caret when ANSI is not available.
204   const auto value = debugger_sp->GetStopShowColumn();
205   if ((value == eStopShowColumnAnsiOrCaret) && !debugger_sp->GetUseColor())
206     return true;
207 
208   // The only other time we use caret is if we're explicitly asked to show
209   // caret.
210   return value == eStopShowColumnCaret;
211 }
212 
213 static bool should_show_stop_line_with_ansi(DebuggerSP debugger_sp) {
214   return debugger_sp && debugger_sp->GetUseColor();
215 }
216 
217 size_t SourceManager::DisplaySourceLinesWithLineNumbersUsingLastFile(
218     uint32_t start_line, uint32_t count, uint32_t curr_line, uint32_t column,
219     const char *current_line_cstr, Stream *s,
220     const SymbolContextList *bp_locs) {
221   if (count == 0)
222     return 0;
223 
224   Stream::ByteDelta delta(*s);
225 
226   if (start_line == 0) {
227     if (m_last_line != 0 && m_last_line != UINT32_MAX)
228       start_line = m_last_line + m_last_count;
229     else
230       start_line = 1;
231   }
232 
233   if (!m_default_set) {
234     FileSpec tmp_spec;
235     uint32_t tmp_line;
236     GetDefaultFileAndLine(tmp_spec, tmp_line);
237   }
238 
239   m_last_line = start_line;
240   m_last_count = count;
241 
242   if (FileSP last_file_sp = GetLastFile()) {
243     const uint32_t end_line = start_line + count - 1;
244     for (uint32_t line = start_line; line <= end_line; ++line) {
245       if (!last_file_sp->LineIsValid(line)) {
246         m_last_line = UINT32_MAX;
247         break;
248       }
249 
250       std::string prefix;
251       if (bp_locs) {
252         uint32_t bp_count = bp_locs->NumLineEntriesWithLine(line);
253 
254         if (bp_count > 0)
255           prefix = llvm::formatv("[{0}]", bp_count);
256         else
257           prefix = "    ";
258       }
259 
260       char buffer[3];
261       snprintf(buffer, sizeof(buffer), "%2.2s",
262                (line == curr_line) ? current_line_cstr : "");
263       std::string current_line_highlight(buffer);
264 
265       auto debugger_sp = m_debugger_wp.lock();
266       if (should_show_stop_line_with_ansi(debugger_sp)) {
267         current_line_highlight = ansi::FormatAnsiTerminalCodes(
268             (debugger_sp->GetStopShowLineMarkerAnsiPrefix() +
269              current_line_highlight +
270              debugger_sp->GetStopShowLineMarkerAnsiSuffix())
271                 .str());
272       }
273 
274       s->Printf("%s%s %-4u\t", prefix.c_str(), current_line_highlight.c_str(),
275                 line);
276 
277       // So far we treated column 0 as a special 'no column value', but
278       // DisplaySourceLines starts counting columns from 0 (and no column is
279       // expressed by passing an empty optional).
280       std::optional<size_t> columnToHighlight;
281       if (line == curr_line && column)
282         columnToHighlight = column - 1;
283 
284       size_t this_line_size =
285           last_file_sp->DisplaySourceLines(line, columnToHighlight, 0, 0, s);
286       if (column != 0 && line == curr_line &&
287           should_show_stop_column_with_caret(debugger_sp)) {
288         // Display caret cursor.
289         std::string src_line;
290         last_file_sp->GetLine(line, src_line);
291         s->Printf("    \t");
292         // Insert a space for every non-tab character in the source line.
293         for (size_t i = 0; i + 1 < column && i < src_line.length(); ++i)
294           s->PutChar(src_line[i] == '\t' ? '\t' : ' ');
295         // Now add the caret.
296         s->Printf("^\n");
297       }
298       if (this_line_size == 0) {
299         m_last_line = UINT32_MAX;
300         break;
301       }
302     }
303   }
304   return *delta;
305 }
306 
307 size_t SourceManager::DisplaySourceLinesWithLineNumbers(
308     const FileSpec &file_spec, uint32_t line, uint32_t column,
309     uint32_t context_before, uint32_t context_after,
310     const char *current_line_cstr, Stream *s,
311     const SymbolContextList *bp_locs) {
312   FileSP file_sp(GetFile(file_spec));
313 
314   uint32_t start_line;
315   uint32_t count = context_before + context_after + 1;
316   if (line > context_before)
317     start_line = line - context_before;
318   else
319     start_line = 1;
320 
321   FileSP last_file_sp(GetLastFile());
322   if (last_file_sp.get() != file_sp.get()) {
323     if (line == 0)
324       m_last_line = 0;
325     m_last_file_spec = file_spec;
326   }
327   return DisplaySourceLinesWithLineNumbersUsingLastFile(
328       start_line, count, line, column, current_line_cstr, s, bp_locs);
329 }
330 
331 size_t SourceManager::DisplayMoreWithLineNumbers(
332     Stream *s, uint32_t count, bool reverse, const SymbolContextList *bp_locs) {
333   // If we get called before anybody has set a default file and line, then try
334   // to figure it out here.
335   FileSP last_file_sp(GetLastFile());
336   const bool have_default_file_line = last_file_sp && m_last_line > 0;
337   if (!m_default_set) {
338     FileSpec tmp_spec;
339     uint32_t tmp_line;
340     GetDefaultFileAndLine(tmp_spec, tmp_line);
341   }
342 
343   if (last_file_sp) {
344     if (m_last_line == UINT32_MAX)
345       return 0;
346 
347     if (reverse && m_last_line == 1)
348       return 0;
349 
350     if (count > 0)
351       m_last_count = count;
352     else if (m_last_count == 0)
353       m_last_count = 10;
354 
355     if (m_last_line > 0) {
356       if (reverse) {
357         // If this is the first time we've done a reverse, then back up one
358         // more time so we end up showing the chunk before the last one we've
359         // shown:
360         if (m_last_line > m_last_count)
361           m_last_line -= m_last_count;
362         else
363           m_last_line = 1;
364       } else if (have_default_file_line)
365         m_last_line += m_last_count;
366     } else
367       m_last_line = 1;
368 
369     const uint32_t column = 0;
370     return DisplaySourceLinesWithLineNumbersUsingLastFile(
371         m_last_line, m_last_count, UINT32_MAX, column, "", s, bp_locs);
372   }
373   return 0;
374 }
375 
376 bool SourceManager::SetDefaultFileAndLine(const FileSpec &file_spec,
377                                           uint32_t line) {
378   m_default_set = true;
379   FileSP file_sp(GetFile(file_spec));
380 
381   if (file_sp) {
382     m_last_line = line;
383     m_last_file_spec = file_spec;
384     return true;
385   } else {
386     return false;
387   }
388 }
389 
390 bool SourceManager::GetDefaultFileAndLine(FileSpec &file_spec, uint32_t &line) {
391   if (FileSP last_file_sp = GetLastFile()) {
392     file_spec = m_last_file_spec;
393     line = m_last_line;
394     return true;
395   } else if (!m_default_set) {
396     TargetSP target_sp(m_target_wp.lock());
397 
398     if (target_sp) {
399       // If nobody has set the default file and line then try here.  If there's
400       // no executable, then we will try again later when there is one.
401       // Otherwise, if we can't find it we won't look again, somebody will have
402       // to set it (for instance when we stop somewhere...)
403       Module *executable_ptr = target_sp->GetExecutableModulePointer();
404       if (executable_ptr) {
405         SymbolContextList sc_list;
406         ConstString main_name("main");
407 
408         ModuleFunctionSearchOptions function_options;
409         function_options.include_symbols =
410             false; // Force it to be a debug symbol.
411         function_options.include_inlines = true;
412         executable_ptr->FindFunctions(main_name, CompilerDeclContext(),
413                                       lldb::eFunctionNameTypeBase,
414                                       function_options, sc_list);
415         for (const SymbolContext &sc : sc_list) {
416           if (sc.function) {
417             lldb_private::LineEntry line_entry;
418             if (sc.function->GetAddressRange()
419                     .GetBaseAddress()
420                     .CalculateSymbolContextLineEntry(line_entry)) {
421               SetDefaultFileAndLine(line_entry.file, line_entry.line);
422               file_spec = m_last_file_spec;
423               line = m_last_line;
424               return true;
425             }
426           }
427         }
428       }
429     }
430   }
431   return false;
432 }
433 
434 void SourceManager::FindLinesMatchingRegex(FileSpec &file_spec,
435                                            RegularExpression &regex,
436                                            uint32_t start_line,
437                                            uint32_t end_line,
438                                            std::vector<uint32_t> &match_lines) {
439   match_lines.clear();
440   FileSP file_sp = GetFile(file_spec);
441   if (!file_sp)
442     return;
443   return file_sp->FindLinesMatchingRegex(regex, start_line, end_line,
444                                          match_lines);
445 }
446 
447 SourceManager::File::File(const FileSpec &file_spec,
448                           lldb::DebuggerSP debugger_sp)
449     : m_file_spec_orig(file_spec), m_file_spec(), m_mod_time(),
450       m_debugger_wp(debugger_sp), m_target_wp(TargetSP()) {
451   CommonInitializer(file_spec, {});
452 }
453 
454 SourceManager::File::File(const FileSpec &file_spec, TargetSP target_sp)
455     : m_file_spec_orig(file_spec), m_file_spec(), m_mod_time(),
456       m_debugger_wp(target_sp ? target_sp->GetDebugger().shared_from_this()
457                               : DebuggerSP()),
458       m_target_wp(target_sp) {
459   CommonInitializer(file_spec, target_sp);
460 }
461 
462 void SourceManager::File::CommonInitializer(const FileSpec &file_spec,
463                                             TargetSP target_sp) {
464   // Set the file and update the modification time.
465   SetFileSpec(file_spec);
466 
467   // Always update the source map modification ID if we have a target.
468   if (target_sp)
469     m_source_map_mod_id = target_sp->GetSourcePathMap().GetModificationID();
470 
471   // File doesn't exist.
472   if (m_mod_time == llvm::sys::TimePoint<>()) {
473     if (target_sp) {
474       // If this is just a file name, try finding it in the target.
475       if (!file_spec.GetDirectory() && file_spec.GetFilename()) {
476         bool check_inlines = false;
477         SymbolContextList sc_list;
478         size_t num_matches =
479             target_sp->GetImages().ResolveSymbolContextForFilePath(
480                 file_spec.GetFilename().AsCString(), 0, check_inlines,
481                 SymbolContextItem(eSymbolContextModule |
482                                   eSymbolContextCompUnit),
483                 sc_list);
484         bool got_multiple = false;
485         if (num_matches != 0) {
486           if (num_matches > 1) {
487             CompileUnit *test_cu = nullptr;
488             for (const SymbolContext &sc : sc_list) {
489               if (sc.comp_unit) {
490                 if (test_cu) {
491                   if (test_cu != sc.comp_unit)
492                     got_multiple = true;
493                   break;
494                 } else
495                   test_cu = sc.comp_unit;
496               }
497             }
498           }
499           if (!got_multiple) {
500             SymbolContext sc;
501             sc_list.GetContextAtIndex(0, sc);
502             if (sc.comp_unit)
503               SetFileSpec(sc.comp_unit->GetPrimaryFile());
504           }
505         }
506       }
507 
508       // Try remapping the file if it doesn't exist.
509       if (!FileSystem::Instance().Exists(m_file_spec)) {
510         // Check target specific source remappings (i.e., the
511         // target.source-map setting), then fall back to the module
512         // specific remapping (i.e., the .dSYM remapping dictionary).
513         auto remapped = target_sp->GetSourcePathMap().FindFile(m_file_spec);
514         if (!remapped) {
515           FileSpec new_spec;
516           if (target_sp->GetImages().FindSourceFile(m_file_spec, new_spec))
517             remapped = new_spec;
518         }
519         if (remapped)
520           SetFileSpec(*remapped);
521       }
522     }
523   }
524 
525   // If the file exists, read in the data.
526   if (m_mod_time != llvm::sys::TimePoint<>())
527     m_data_sp = FileSystem::Instance().CreateDataBuffer(m_file_spec);
528 }
529 
530 void SourceManager::File::SetFileSpec(FileSpec file_spec) {
531   resolve_tilde(file_spec);
532   m_file_spec = std::move(file_spec);
533   m_mod_time = FileSystem::Instance().GetModificationTime(m_file_spec);
534 }
535 
536 uint32_t SourceManager::File::GetLineOffset(uint32_t line) {
537   if (line == 0)
538     return UINT32_MAX;
539 
540   if (line == 1)
541     return 0;
542 
543   if (CalculateLineOffsets(line)) {
544     if (line < m_offsets.size())
545       return m_offsets[line - 1]; // yes we want "line - 1" in the index
546   }
547   return UINT32_MAX;
548 }
549 
550 uint32_t SourceManager::File::GetNumLines() {
551   CalculateLineOffsets();
552   return m_offsets.size();
553 }
554 
555 const char *SourceManager::File::PeekLineData(uint32_t line) {
556   if (!LineIsValid(line))
557     return nullptr;
558 
559   size_t line_offset = GetLineOffset(line);
560   if (line_offset < m_data_sp->GetByteSize())
561     return (const char *)m_data_sp->GetBytes() + line_offset;
562   return nullptr;
563 }
564 
565 uint32_t SourceManager::File::GetLineLength(uint32_t line,
566                                             bool include_newline_chars) {
567   if (!LineIsValid(line))
568     return false;
569 
570   size_t start_offset = GetLineOffset(line);
571   size_t end_offset = GetLineOffset(line + 1);
572   if (end_offset == UINT32_MAX)
573     end_offset = m_data_sp->GetByteSize();
574 
575   if (end_offset > start_offset) {
576     uint32_t length = end_offset - start_offset;
577     if (!include_newline_chars) {
578       const char *line_start =
579           (const char *)m_data_sp->GetBytes() + start_offset;
580       while (length > 0) {
581         const char last_char = line_start[length - 1];
582         if ((last_char == '\r') || (last_char == '\n'))
583           --length;
584         else
585           break;
586       }
587     }
588     return length;
589   }
590   return 0;
591 }
592 
593 bool SourceManager::File::LineIsValid(uint32_t line) {
594   if (line == 0)
595     return false;
596 
597   if (CalculateLineOffsets(line))
598     return line < m_offsets.size();
599   return false;
600 }
601 
602 bool SourceManager::File::ModificationTimeIsStale() const {
603   // TODO: use host API to sign up for file modifications to anything in our
604   // source cache and only update when we determine a file has been updated.
605   // For now we check each time we want to display info for the file.
606   auto curr_mod_time = FileSystem::Instance().GetModificationTime(m_file_spec);
607   return curr_mod_time != llvm::sys::TimePoint<>() &&
608          m_mod_time != curr_mod_time;
609 }
610 
611 bool SourceManager::File::PathRemappingIsStale() const {
612   if (TargetSP target_sp = m_target_wp.lock())
613     return GetSourceMapModificationID() !=
614            target_sp->GetSourcePathMap().GetModificationID();
615   return false;
616 }
617 
618 size_t SourceManager::File::DisplaySourceLines(uint32_t line,
619                                                std::optional<size_t> column,
620                                                uint32_t context_before,
621                                                uint32_t context_after,
622                                                Stream *s) {
623   // Nothing to write if there's no stream.
624   if (!s)
625     return 0;
626 
627   // Sanity check m_data_sp before proceeding.
628   if (!m_data_sp)
629     return 0;
630 
631   size_t bytes_written = s->GetWrittenBytes();
632 
633   auto debugger_sp = m_debugger_wp.lock();
634 
635   HighlightStyle style;
636   // Use the default Vim style if source highlighting is enabled.
637   if (should_highlight_source(debugger_sp))
638     style = HighlightStyle::MakeVimStyle();
639 
640   // If we should mark the stop column with color codes, then copy the prefix
641   // and suffix to our color style.
642   if (should_show_stop_column_with_ansi(debugger_sp))
643     style.selected.Set(debugger_sp->GetStopShowColumnAnsiPrefix(),
644                        debugger_sp->GetStopShowColumnAnsiSuffix());
645 
646   HighlighterManager mgr;
647   std::string path = GetFileSpec().GetPath(/*denormalize*/ false);
648   // FIXME: Find a way to get the definitive language this file was written in
649   // and pass it to the highlighter.
650   const auto &h = mgr.getHighlighterFor(lldb::eLanguageTypeUnknown, path);
651 
652   const uint32_t start_line =
653       line <= context_before ? 1 : line - context_before;
654   const uint32_t start_line_offset = GetLineOffset(start_line);
655   if (start_line_offset != UINT32_MAX) {
656     const uint32_t end_line = line + context_after;
657     uint32_t end_line_offset = GetLineOffset(end_line + 1);
658     if (end_line_offset == UINT32_MAX)
659       end_line_offset = m_data_sp->GetByteSize();
660 
661     assert(start_line_offset <= end_line_offset);
662     if (start_line_offset < end_line_offset) {
663       size_t count = end_line_offset - start_line_offset;
664       const uint8_t *cstr = m_data_sp->GetBytes() + start_line_offset;
665 
666       auto ref = llvm::StringRef(reinterpret_cast<const char *>(cstr), count);
667 
668       h.Highlight(style, ref, column, "", *s);
669 
670       // Ensure we get an end of line character one way or another.
671       if (!is_newline_char(ref.back()))
672         s->EOL();
673     }
674   }
675   return s->GetWrittenBytes() - bytes_written;
676 }
677 
678 void SourceManager::File::FindLinesMatchingRegex(
679     RegularExpression &regex, uint32_t start_line, uint32_t end_line,
680     std::vector<uint32_t> &match_lines) {
681   match_lines.clear();
682 
683   if (!LineIsValid(start_line) ||
684       (end_line != UINT32_MAX && !LineIsValid(end_line)))
685     return;
686   if (start_line > end_line)
687     return;
688 
689   for (uint32_t line_no = start_line; line_no < end_line; line_no++) {
690     std::string buffer;
691     if (!GetLine(line_no, buffer))
692       break;
693     if (regex.Execute(buffer)) {
694       match_lines.push_back(line_no);
695     }
696   }
697 }
698 
699 bool lldb_private::operator==(const SourceManager::File &lhs,
700                               const SourceManager::File &rhs) {
701   if (lhs.m_file_spec != rhs.m_file_spec)
702     return false;
703   return lhs.m_mod_time == rhs.m_mod_time;
704 }
705 
706 bool SourceManager::File::CalculateLineOffsets(uint32_t line) {
707   line =
708       UINT32_MAX; // TODO: take this line out when we support partial indexing
709   if (line == UINT32_MAX) {
710     // Already done?
711     if (!m_offsets.empty() && m_offsets[0] == UINT32_MAX)
712       return true;
713 
714     if (m_offsets.empty()) {
715       if (m_data_sp.get() == nullptr)
716         return false;
717 
718       const char *start = (const char *)m_data_sp->GetBytes();
719       if (start) {
720         const char *end = start + m_data_sp->GetByteSize();
721 
722         // Calculate all line offsets from scratch
723 
724         // Push a 1 at index zero to indicate the file has been completely
725         // indexed.
726         m_offsets.push_back(UINT32_MAX);
727         const char *s;
728         for (s = start; s < end; ++s) {
729           char curr_ch = *s;
730           if (is_newline_char(curr_ch)) {
731             if (s + 1 < end) {
732               char next_ch = s[1];
733               if (is_newline_char(next_ch)) {
734                 if (curr_ch != next_ch)
735                   ++s;
736               }
737             }
738             m_offsets.push_back(s + 1 - start);
739           }
740         }
741         if (!m_offsets.empty()) {
742           if (m_offsets.back() < size_t(end - start))
743             m_offsets.push_back(end - start);
744         }
745         return true;
746       }
747     } else {
748       // Some lines have been populated, start where we last left off
749       assert("Not implemented yet" && false);
750     }
751 
752   } else {
753     // Calculate all line offsets up to "line"
754     assert("Not implemented yet" && false);
755   }
756   return false;
757 }
758 
759 bool SourceManager::File::GetLine(uint32_t line_no, std::string &buffer) {
760   if (!LineIsValid(line_no))
761     return false;
762 
763   size_t start_offset = GetLineOffset(line_no);
764   size_t end_offset = GetLineOffset(line_no + 1);
765   if (end_offset == UINT32_MAX) {
766     end_offset = m_data_sp->GetByteSize();
767   }
768   buffer.assign((const char *)m_data_sp->GetBytes() + start_offset,
769                 end_offset - start_offset);
770 
771   return true;
772 }
773 
774 void SourceManager::SourceFileCache::AddSourceFile(const FileSpec &file_spec,
775                                                    FileSP file_sp) {
776   llvm::sys::ScopedWriter guard(m_mutex);
777 
778   assert(file_sp && "invalid FileSP");
779 
780   AddSourceFileImpl(file_spec, file_sp);
781   const FileSpec &resolved_file_spec = file_sp->GetFileSpec();
782   if (file_spec != resolved_file_spec)
783     AddSourceFileImpl(file_sp->GetFileSpec(), file_sp);
784 }
785 
786 void SourceManager::SourceFileCache::RemoveSourceFile(const FileSP &file_sp) {
787   llvm::sys::ScopedWriter guard(m_mutex);
788 
789   assert(file_sp && "invalid FileSP");
790 
791   // Iterate over all the elements in the cache.
792   // This is expensive but a relatively uncommon operation.
793   auto it = m_file_cache.begin();
794   while (it != m_file_cache.end()) {
795     if (it->second == file_sp)
796       it = m_file_cache.erase(it);
797     else
798       it++;
799   }
800 }
801 
802 void SourceManager::SourceFileCache::AddSourceFileImpl(
803     const FileSpec &file_spec, FileSP file_sp) {
804   FileCache::iterator pos = m_file_cache.find(file_spec);
805   if (pos == m_file_cache.end()) {
806     m_file_cache[file_spec] = file_sp;
807   } else {
808     if (file_sp != pos->second)
809       m_file_cache[file_spec] = file_sp;
810   }
811 }
812 
813 SourceManager::FileSP SourceManager::SourceFileCache::FindSourceFile(
814     const FileSpec &file_spec) const {
815   llvm::sys::ScopedReader guard(m_mutex);
816 
817   FileCache::const_iterator pos = m_file_cache.find(file_spec);
818   if (pos != m_file_cache.end())
819     return pos->second;
820   return {};
821 }
822 
823 void SourceManager::SourceFileCache::Dump(Stream &stream) const {
824   stream << "Modification time   Lines    Path\n";
825   stream << "------------------- -------- --------------------------------\n";
826   for (auto &entry : m_file_cache) {
827     if (!entry.second)
828       continue;
829     FileSP file = entry.second;
830     stream.Format("{0:%Y-%m-%d %H:%M:%S} {1,8:d} {2}\n", file->GetTimestamp(),
831                   file->GetNumLines(), entry.first.GetPath());
832   }
833 }
834