1 //===-- Section.cpp ---------------------------------------------*- C++ -*-===//
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 #include "lldb/Core/Section.h"
11 #include "lldb/Core/Address.h" // for Address
12 #include "lldb/Core/Module.h"
13 #include "lldb/Symbol/ObjectFile.h"
14 #include "lldb/Target/SectionLoadList.h"
15 #include "lldb/Target/Target.h"
16 #include "lldb/Utility/FileSpec.h" // for FileSpec
17 #include "lldb/Utility/Stream.h"   // for Stream
18 #include "lldb/Utility/VMRange.h"  // for VMRange
19 
20 #include <inttypes.h> // for PRIx64
21 #include <limits>     // for numeric_limits
22 #include <utility>    // for distance
23 
24 namespace lldb_private {
25 class DataExtractor;
26 }
27 using namespace lldb;
28 using namespace lldb_private;
29 
30 static const char *GetSectionTypeAsCString(lldb::SectionType sect_type) {
31   switch (sect_type) {
32   case eSectionTypeInvalid:
33     return "invalid";
34   case eSectionTypeCode:
35     return "code";
36   case eSectionTypeContainer:
37     return "container";
38   case eSectionTypeData:
39     return "data";
40   case eSectionTypeDataCString:
41     return "data-cstr";
42   case eSectionTypeDataCStringPointers:
43     return "data-cstr-ptr";
44   case eSectionTypeDataSymbolAddress:
45     return "data-symbol-addr";
46   case eSectionTypeData4:
47     return "data-4-byte";
48   case eSectionTypeData8:
49     return "data-8-byte";
50   case eSectionTypeData16:
51     return "data-16-byte";
52   case eSectionTypeDataPointers:
53     return "data-ptrs";
54   case eSectionTypeDebug:
55     return "debug";
56   case eSectionTypeZeroFill:
57     return "zero-fill";
58   case eSectionTypeDataObjCMessageRefs:
59     return "objc-message-refs";
60   case eSectionTypeDataObjCCFStrings:
61     return "objc-cfstrings";
62   case eSectionTypeDWARFDebugAbbrev:
63     return "dwarf-abbrev";
64   case eSectionTypeDWARFDebugAddr:
65     return "dwarf-addr";
66   case eSectionTypeDWARFDebugAranges:
67     return "dwarf-aranges";
68   case eSectionTypeDWARFDebugFrame:
69     return "dwarf-frame";
70   case eSectionTypeDWARFDebugInfo:
71     return "dwarf-info";
72   case eSectionTypeDWARFDebugLine:
73     return "dwarf-line";
74   case eSectionTypeDWARFDebugLoc:
75     return "dwarf-loc";
76   case eSectionTypeDWARFDebugMacInfo:
77     return "dwarf-macinfo";
78   case eSectionTypeDWARFDebugMacro:
79     return "dwarf-macro";
80   case eSectionTypeDWARFDebugPubNames:
81     return "dwarf-pubnames";
82   case eSectionTypeDWARFDebugPubTypes:
83     return "dwarf-pubtypes";
84   case eSectionTypeDWARFDebugRanges:
85     return "dwarf-ranges";
86   case eSectionTypeDWARFDebugStr:
87     return "dwarf-str";
88   case eSectionTypeDWARFDebugStrOffsets:
89     return "dwarf-str-offsets";
90   case eSectionTypeELFSymbolTable:
91     return "elf-symbol-table";
92   case eSectionTypeELFDynamicSymbols:
93     return "elf-dynamic-symbols";
94   case eSectionTypeELFRelocationEntries:
95     return "elf-relocation-entries";
96   case eSectionTypeELFDynamicLinkInfo:
97     return "elf-dynamic-link-info";
98   case eSectionTypeDWARFAppleNames:
99     return "apple-names";
100   case eSectionTypeDWARFAppleTypes:
101     return "apple-types";
102   case eSectionTypeDWARFAppleNamespaces:
103     return "apple-namespaces";
104   case eSectionTypeDWARFAppleObjC:
105     return "apple-objc";
106   case eSectionTypeEHFrame:
107     return "eh-frame";
108   case eSectionTypeARMexidx:
109     return "ARM.exidx";
110   case eSectionTypeARMextab:
111     return "ARM.extab";
112   case eSectionTypeCompactUnwind:
113     return "compact-unwind";
114   case eSectionTypeGoSymtab:
115     return "go-symtab";
116   case eSectionTypeAbsoluteAddress:
117     return "absolute";
118   case eSectionTypeOther:
119     return "regular";
120   }
121   return "unknown";
122 }
123 
124 Section::Section(const ModuleSP &module_sp, ObjectFile *obj_file,
125                  user_id_t sect_id, const ConstString &name,
126                  SectionType sect_type, addr_t file_addr, addr_t byte_size,
127                  lldb::offset_t file_offset, lldb::offset_t file_size,
128                  uint32_t log2align, uint32_t flags,
129                  uint32_t target_byte_size /*=1*/)
130     : ModuleChild(module_sp), UserID(sect_id), Flags(flags),
131       m_obj_file(obj_file), m_type(sect_type), m_parent_wp(), m_name(name),
132       m_file_addr(file_addr), m_byte_size(byte_size),
133       m_file_offset(file_offset), m_file_size(file_size),
134       m_log2align(log2align), m_children(), m_fake(false), m_encrypted(false),
135       m_thread_specific(false), m_readable(false), m_writable(false),
136       m_executable(false), m_target_byte_size(target_byte_size) {
137   //    printf ("Section::Section(%p): module=%p, sect_id = 0x%16.16" PRIx64 ",
138   //    addr=[0x%16.16" PRIx64 " - 0x%16.16" PRIx64 "), file [0x%16.16" PRIx64 "
139   //    - 0x%16.16" PRIx64 "), flags = 0x%8.8x, name = %s\n",
140   //            this, module_sp.get(), sect_id, file_addr, file_addr +
141   //            byte_size, file_offset, file_offset + file_size, flags,
142   //            name.GetCString());
143 }
144 
145 Section::Section(const lldb::SectionSP &parent_section_sp,
146                  const ModuleSP &module_sp, ObjectFile *obj_file,
147                  user_id_t sect_id, const ConstString &name,
148                  SectionType sect_type, addr_t file_addr, addr_t byte_size,
149                  lldb::offset_t file_offset, lldb::offset_t file_size,
150                  uint32_t log2align, uint32_t flags,
151                  uint32_t target_byte_size /*=1*/)
152     : ModuleChild(module_sp), UserID(sect_id), Flags(flags),
153       m_obj_file(obj_file), m_type(sect_type), m_parent_wp(), m_name(name),
154       m_file_addr(file_addr), m_byte_size(byte_size),
155       m_file_offset(file_offset), m_file_size(file_size),
156       m_log2align(log2align), m_children(), m_fake(false), m_encrypted(false),
157       m_thread_specific(false), m_readable(false), m_writable(false),
158       m_executable(false), m_target_byte_size(target_byte_size) {
159   //    printf ("Section::Section(%p): module=%p, sect_id = 0x%16.16" PRIx64 ",
160   //    addr=[0x%16.16" PRIx64 " - 0x%16.16" PRIx64 "), file [0x%16.16" PRIx64 "
161   //    - 0x%16.16" PRIx64 "), flags = 0x%8.8x, name = %s.%s\n",
162   //            this, module_sp.get(), sect_id, file_addr, file_addr +
163   //            byte_size, file_offset, file_offset + file_size, flags,
164   //            parent_section_sp->GetName().GetCString(), name.GetCString());
165   if (parent_section_sp)
166     m_parent_wp = parent_section_sp;
167 }
168 
169 Section::~Section() {
170   //    printf ("Section::~Section(%p)\n", this);
171 }
172 
173 addr_t Section::GetFileAddress() const {
174   SectionSP parent_sp(GetParent());
175   if (parent_sp) {
176     // This section has a parent which means m_file_addr is an offset into
177     // the parent section, so the file address for this section is the file
178     // address of the parent plus the offset
179     return parent_sp->GetFileAddress() + m_file_addr;
180   }
181   // This section has no parent, so m_file_addr is the file base address
182   return m_file_addr;
183 }
184 
185 bool Section::SetFileAddress(lldb::addr_t file_addr) {
186   SectionSP parent_sp(GetParent());
187   if (parent_sp) {
188     if (m_file_addr >= file_addr)
189       return parent_sp->SetFileAddress(m_file_addr - file_addr);
190     return false;
191   } else {
192     // This section has no parent, so m_file_addr is the file base address
193     m_file_addr = file_addr;
194     return true;
195   }
196 }
197 
198 lldb::addr_t Section::GetOffset() const {
199   // This section has a parent which means m_file_addr is an offset.
200   SectionSP parent_sp(GetParent());
201   if (parent_sp)
202     return m_file_addr;
203 
204   // This section has no parent, so there is no offset to be had
205   return 0;
206 }
207 
208 addr_t Section::GetLoadBaseAddress(Target *target) const {
209   addr_t load_base_addr = LLDB_INVALID_ADDRESS;
210   SectionSP parent_sp(GetParent());
211   if (parent_sp) {
212     load_base_addr = parent_sp->GetLoadBaseAddress(target);
213     if (load_base_addr != LLDB_INVALID_ADDRESS)
214       load_base_addr += GetOffset();
215   }
216   if (load_base_addr == LLDB_INVALID_ADDRESS) {
217     load_base_addr = target->GetSectionLoadList().GetSectionLoadAddress(
218         const_cast<Section *>(this)->shared_from_this());
219   }
220   return load_base_addr;
221 }
222 
223 bool Section::ResolveContainedAddress(addr_t offset, Address &so_addr) const {
224   const size_t num_children = m_children.GetSize();
225   if (num_children > 0) {
226     for (size_t i = 0; i < num_children; i++) {
227       Section *child_section = m_children.GetSectionAtIndex(i).get();
228 
229       addr_t child_offset = child_section->GetOffset();
230       if (child_offset <= offset &&
231           offset - child_offset < child_section->GetByteSize())
232         return child_section->ResolveContainedAddress(offset - child_offset,
233                                                       so_addr);
234     }
235   }
236   so_addr.SetOffset(offset);
237   so_addr.SetSection(const_cast<Section *>(this)->shared_from_this());
238 
239 #ifdef LLDB_CONFIGURATION_DEBUG
240   // For debug builds, ensure that there are no orphaned (i.e., moduleless)
241   // sections.
242   assert(GetModule().get());
243 #endif
244   return true;
245 }
246 
247 bool Section::ContainsFileAddress(addr_t vm_addr) const {
248   const addr_t file_addr = GetFileAddress();
249   if (file_addr != LLDB_INVALID_ADDRESS) {
250     if (file_addr <= vm_addr) {
251       const addr_t offset = (vm_addr - file_addr) * m_target_byte_size;
252       return offset < GetByteSize();
253     }
254   }
255   return false;
256 }
257 
258 int Section::Compare(const Section &a, const Section &b) {
259   if (&a == &b)
260     return 0;
261 
262   const ModuleSP a_module_sp = a.GetModule();
263   const ModuleSP b_module_sp = b.GetModule();
264   if (a_module_sp == b_module_sp) {
265     user_id_t a_sect_uid = a.GetID();
266     user_id_t b_sect_uid = b.GetID();
267     if (a_sect_uid < b_sect_uid)
268       return -1;
269     if (a_sect_uid > b_sect_uid)
270       return 1;
271     return 0;
272   } else {
273     // The modules are different, just compare the module pointers
274     if (a_module_sp.get() < b_module_sp.get())
275       return -1;
276     else
277       return 1; // We already know the modules aren't equal
278   }
279 }
280 
281 void Section::Dump(Stream *s, Target *target, uint32_t depth) const {
282   //    s->Printf("%.*p: ", (int)sizeof(void*) * 2, this);
283   s->Indent();
284   s->Printf("0x%8.8" PRIx64 " %-16s ", GetID(),
285             GetSectionTypeAsCString(m_type));
286   bool resolved = true;
287   addr_t addr = LLDB_INVALID_ADDRESS;
288 
289   if (GetByteSize() == 0)
290     s->Printf("%39s", "");
291   else {
292     if (target)
293       addr = GetLoadBaseAddress(target);
294 
295     if (addr == LLDB_INVALID_ADDRESS) {
296       if (target)
297         resolved = false;
298       addr = GetFileAddress();
299     }
300 
301     VMRange range(addr, addr + m_byte_size);
302     range.Dump(s, 0);
303   }
304 
305   s->Printf("%c %c%c%c  0x%8.8" PRIx64 " 0x%8.8" PRIx64 " 0x%8.8x ",
306             resolved ? ' ' : '*', m_readable ? 'r' : '-',
307             m_writable ? 'w' : '-', m_executable ? 'x' : '-', m_file_offset,
308             m_file_size, Get());
309 
310   DumpName(s);
311 
312   s->EOL();
313 
314   if (depth > 0)
315     m_children.Dump(s, target, false, depth - 1);
316 }
317 
318 void Section::DumpName(Stream *s) const {
319   SectionSP parent_sp(GetParent());
320   if (parent_sp) {
321     parent_sp->DumpName(s);
322     s->PutChar('.');
323   } else {
324     // The top most section prints the module basename
325     const char *name = NULL;
326     ModuleSP module_sp(GetModule());
327     const FileSpec &file_spec = m_obj_file->GetFileSpec();
328 
329     if (m_obj_file)
330       name = file_spec.GetFilename().AsCString();
331     if ((!name || !name[0]) && module_sp)
332       name = module_sp->GetFileSpec().GetFilename().AsCString();
333     if (name && name[0])
334       s->Printf("%s.", name);
335   }
336   m_name.Dump(s);
337 }
338 
339 bool Section::IsDescendant(const Section *section) {
340   if (this == section)
341     return true;
342   SectionSP parent_sp(GetParent());
343   if (parent_sp)
344     return parent_sp->IsDescendant(section);
345   return false;
346 }
347 
348 bool Section::Slide(addr_t slide_amount, bool slide_children) {
349   if (m_file_addr != LLDB_INVALID_ADDRESS) {
350     if (slide_amount == 0)
351       return true;
352 
353     m_file_addr += slide_amount;
354 
355     if (slide_children)
356       m_children.Slide(slide_amount, slide_children);
357 
358     return true;
359   }
360   return false;
361 }
362 
363 //------------------------------------------------------------------
364 /// Get the permissions as OR'ed bits from lldb::Permissions
365 //------------------------------------------------------------------
366 uint32_t Section::GetPermissions() const {
367   uint32_t permissions = 0;
368   if (m_readable)
369     permissions |= ePermissionsReadable;
370   if (m_writable)
371     permissions |= ePermissionsWritable;
372   if (m_executable)
373     permissions |= ePermissionsExecutable;
374   return permissions;
375 }
376 
377 //------------------------------------------------------------------
378 /// Set the permissions using bits OR'ed from lldb::Permissions
379 //------------------------------------------------------------------
380 void Section::SetPermissions(uint32_t permissions) {
381   m_readable = (permissions & ePermissionsReadable) != 0;
382   m_writable = (permissions & ePermissionsWritable) != 0;
383   m_executable = (permissions & ePermissionsExecutable) != 0;
384 }
385 
386 lldb::offset_t Section::GetSectionData(void *dst, lldb::offset_t dst_len,
387                                        lldb::offset_t offset) {
388   if (m_obj_file)
389     return m_obj_file->ReadSectionData(this, offset, dst, dst_len);
390   return 0;
391 }
392 
393 lldb::offset_t Section::GetSectionData(DataExtractor &section_data) const {
394   if (m_obj_file)
395     return m_obj_file->ReadSectionData(this, section_data);
396   return 0;
397 }
398 
399 #pragma mark SectionList
400 
401 SectionList::SectionList() : m_sections() {}
402 
403 SectionList::~SectionList() {}
404 
405 SectionList &SectionList::operator=(const SectionList &rhs) {
406   if (this != &rhs)
407     m_sections = rhs.m_sections;
408   return *this;
409 }
410 
411 size_t SectionList::AddSection(const lldb::SectionSP &section_sp) {
412   if (section_sp) {
413     size_t section_index = m_sections.size();
414     m_sections.push_back(section_sp);
415     return section_index;
416   }
417 
418   return std::numeric_limits<size_t>::max();
419 }
420 
421 // Warning, this can be slow as it's removing items from a std::vector.
422 bool SectionList::DeleteSection(size_t idx) {
423   if (idx < m_sections.size()) {
424     m_sections.erase(m_sections.begin() + idx);
425     return true;
426   }
427   return false;
428 }
429 
430 size_t SectionList::FindSectionIndex(const Section *sect) {
431   iterator sect_iter;
432   iterator begin = m_sections.begin();
433   iterator end = m_sections.end();
434   for (sect_iter = begin; sect_iter != end; ++sect_iter) {
435     if (sect_iter->get() == sect) {
436       // The secton was already in this section list
437       return std::distance(begin, sect_iter);
438     }
439   }
440   return UINT32_MAX;
441 }
442 
443 size_t SectionList::AddUniqueSection(const lldb::SectionSP &sect_sp) {
444   size_t sect_idx = FindSectionIndex(sect_sp.get());
445   if (sect_idx == UINT32_MAX) {
446     sect_idx = AddSection(sect_sp);
447   }
448   return sect_idx;
449 }
450 
451 bool SectionList::ReplaceSection(user_id_t sect_id,
452                                  const lldb::SectionSP &sect_sp,
453                                  uint32_t depth) {
454   iterator sect_iter, end = m_sections.end();
455   for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
456     if ((*sect_iter)->GetID() == sect_id) {
457       *sect_iter = sect_sp;
458       return true;
459     } else if (depth > 0) {
460       if ((*sect_iter)
461               ->GetChildren()
462               .ReplaceSection(sect_id, sect_sp, depth - 1))
463         return true;
464     }
465   }
466   return false;
467 }
468 
469 size_t SectionList::GetNumSections(uint32_t depth) const {
470   size_t count = m_sections.size();
471   if (depth > 0) {
472     const_iterator sect_iter, end = m_sections.end();
473     for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
474       count += (*sect_iter)->GetChildren().GetNumSections(depth - 1);
475     }
476   }
477   return count;
478 }
479 
480 SectionSP SectionList::GetSectionAtIndex(size_t idx) const {
481   SectionSP sect_sp;
482   if (idx < m_sections.size())
483     sect_sp = m_sections[idx];
484   return sect_sp;
485 }
486 
487 SectionSP
488 SectionList::FindSectionByName(const ConstString &section_dstr) const {
489   SectionSP sect_sp;
490   // Check if we have a valid section string
491   if (section_dstr && !m_sections.empty()) {
492     const_iterator sect_iter;
493     const_iterator end = m_sections.end();
494     for (sect_iter = m_sections.begin();
495          sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
496       Section *child_section = sect_iter->get();
497       if (child_section) {
498         if (child_section->GetName() == section_dstr) {
499           sect_sp = *sect_iter;
500         } else {
501           sect_sp =
502               child_section->GetChildren().FindSectionByName(section_dstr);
503         }
504       }
505     }
506   }
507   return sect_sp;
508 }
509 
510 SectionSP SectionList::FindSectionByID(user_id_t sect_id) const {
511   SectionSP sect_sp;
512   if (sect_id) {
513     const_iterator sect_iter;
514     const_iterator end = m_sections.end();
515     for (sect_iter = m_sections.begin();
516          sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
517       if ((*sect_iter)->GetID() == sect_id) {
518         sect_sp = *sect_iter;
519         break;
520       } else {
521         sect_sp = (*sect_iter)->GetChildren().FindSectionByID(sect_id);
522       }
523     }
524   }
525   return sect_sp;
526 }
527 
528 SectionSP SectionList::FindSectionByType(SectionType sect_type,
529                                          bool check_children,
530                                          size_t start_idx) const {
531   SectionSP sect_sp;
532   size_t num_sections = m_sections.size();
533   for (size_t idx = start_idx; idx < num_sections; ++idx) {
534     if (m_sections[idx]->GetType() == sect_type) {
535       sect_sp = m_sections[idx];
536       break;
537     } else if (check_children) {
538       sect_sp = m_sections[idx]->GetChildren().FindSectionByType(
539           sect_type, check_children, 0);
540       if (sect_sp)
541         break;
542     }
543   }
544   return sect_sp;
545 }
546 
547 SectionSP SectionList::FindSectionContainingFileAddress(addr_t vm_addr,
548                                                         uint32_t depth) const {
549   SectionSP sect_sp;
550   const_iterator sect_iter;
551   const_iterator end = m_sections.end();
552   for (sect_iter = m_sections.begin();
553        sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
554     Section *sect = sect_iter->get();
555     if (sect->ContainsFileAddress(vm_addr)) {
556       // The file address is in this section. We need to make sure one of our
557       // child
558       // sections doesn't contain this address as well as obeying the depth
559       // limit
560       // that was passed in.
561       if (depth > 0)
562         sect_sp = sect->GetChildren().FindSectionContainingFileAddress(
563             vm_addr, depth - 1);
564 
565       if (sect_sp.get() == NULL && !sect->IsFake())
566         sect_sp = *sect_iter;
567     }
568   }
569   return sect_sp;
570 }
571 
572 bool SectionList::ContainsSection(user_id_t sect_id) const {
573   return FindSectionByID(sect_id).get() != NULL;
574 }
575 
576 void SectionList::Dump(Stream *s, Target *target, bool show_header,
577                        uint32_t depth) const {
578   bool target_has_loaded_sections =
579       target && !target->GetSectionLoadList().IsEmpty();
580   if (show_header && !m_sections.empty()) {
581     s->Indent();
582     s->Printf("SectID     Type             %s Address                          "
583               "   Perm File Off.  File Size  Flags "
584               "     Section Name\n",
585               target_has_loaded_sections ? "Load" : "File");
586     s->Indent();
587     s->PutCString("---------- ---------------- "
588                   "---------------------------------------  ---- ---------- "
589                   "---------- "
590                   "---------- ----------------------------\n");
591   }
592 
593   const_iterator sect_iter;
594   const_iterator end = m_sections.end();
595   for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
596     (*sect_iter)->Dump(s, target_has_loaded_sections ? target : NULL, depth);
597   }
598 
599   if (show_header && !m_sections.empty())
600     s->IndentLess();
601 }
602 
603 size_t SectionList::Slide(addr_t slide_amount, bool slide_children) {
604   size_t count = 0;
605   const_iterator pos, end = m_sections.end();
606   for (pos = m_sections.begin(); pos != end; ++pos) {
607     if ((*pos)->Slide(slide_amount, slide_children))
608       ++count;
609   }
610   return count;
611 }
612