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 const char *Section::GetTypeAsCString() const {
31   switch (m_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 eSectionTypeDWARFDebugCuIndex:
69     return "dwarf-cu-index";
70   case eSectionTypeDWARFDebugFrame:
71     return "dwarf-frame";
72   case eSectionTypeDWARFDebugInfo:
73     return "dwarf-info";
74   case eSectionTypeDWARFDebugLine:
75     return "dwarf-line";
76   case eSectionTypeDWARFDebugLineStr:
77     return "dwarf-line-str";
78   case eSectionTypeDWARFDebugLoc:
79     return "dwarf-loc";
80   case eSectionTypeDWARFDebugMacInfo:
81     return "dwarf-macinfo";
82   case eSectionTypeDWARFDebugMacro:
83     return "dwarf-macro";
84   case eSectionTypeDWARFDebugPubNames:
85     return "dwarf-pubnames";
86   case eSectionTypeDWARFDebugPubTypes:
87     return "dwarf-pubtypes";
88   case eSectionTypeDWARFDebugRanges:
89     return "dwarf-ranges";
90   case eSectionTypeDWARFDebugStr:
91     return "dwarf-str";
92   case eSectionTypeDWARFDebugStrOffsets:
93     return "dwarf-str-offsets";
94   case eSectionTypeDWARFDebugTypes:
95     return "dwarf-types";
96   case eSectionTypeDWARFDebugNames:
97     return "dwarf-names";
98   case eSectionTypeELFSymbolTable:
99     return "elf-symbol-table";
100   case eSectionTypeELFDynamicSymbols:
101     return "elf-dynamic-symbols";
102   case eSectionTypeELFRelocationEntries:
103     return "elf-relocation-entries";
104   case eSectionTypeELFDynamicLinkInfo:
105     return "elf-dynamic-link-info";
106   case eSectionTypeDWARFAppleNames:
107     return "apple-names";
108   case eSectionTypeDWARFAppleTypes:
109     return "apple-types";
110   case eSectionTypeDWARFAppleNamespaces:
111     return "apple-namespaces";
112   case eSectionTypeDWARFAppleObjC:
113     return "apple-objc";
114   case eSectionTypeEHFrame:
115     return "eh-frame";
116   case eSectionTypeARMexidx:
117     return "ARM.exidx";
118   case eSectionTypeARMextab:
119     return "ARM.extab";
120   case eSectionTypeCompactUnwind:
121     return "compact-unwind";
122   case eSectionTypeGoSymtab:
123     return "go-symtab";
124   case eSectionTypeAbsoluteAddress:
125     return "absolute";
126   case eSectionTypeDWARFGNUDebugAltLink:
127     return "dwarf-gnu-debugaltlink";
128   case eSectionTypeOther:
129     return "regular";
130   }
131   return "unknown";
132 }
133 
134 Section::Section(const ModuleSP &module_sp, ObjectFile *obj_file,
135                  user_id_t sect_id, const ConstString &name,
136                  SectionType sect_type, addr_t file_addr, addr_t byte_size,
137                  lldb::offset_t file_offset, lldb::offset_t file_size,
138                  uint32_t log2align, uint32_t flags,
139                  uint32_t target_byte_size /*=1*/)
140     : ModuleChild(module_sp), UserID(sect_id), Flags(flags),
141       m_obj_file(obj_file), m_type(sect_type), m_parent_wp(), m_name(name),
142       m_file_addr(file_addr), m_byte_size(byte_size),
143       m_file_offset(file_offset), m_file_size(file_size),
144       m_log2align(log2align), m_children(), m_fake(false), m_encrypted(false),
145       m_thread_specific(false), m_readable(false), m_writable(false),
146       m_executable(false), m_relocated(false), m_target_byte_size(target_byte_size) {
147   //    printf ("Section::Section(%p): module=%p, sect_id = 0x%16.16" PRIx64 ",
148   //    addr=[0x%16.16" PRIx64 " - 0x%16.16" PRIx64 "), file [0x%16.16" PRIx64 "
149   //    - 0x%16.16" PRIx64 "), flags = 0x%8.8x, name = %s\n",
150   //            this, module_sp.get(), sect_id, file_addr, file_addr +
151   //            byte_size, file_offset, file_offset + file_size, flags,
152   //            name.GetCString());
153 }
154 
155 Section::Section(const lldb::SectionSP &parent_section_sp,
156                  const ModuleSP &module_sp, ObjectFile *obj_file,
157                  user_id_t sect_id, const ConstString &name,
158                  SectionType sect_type, addr_t file_addr, addr_t byte_size,
159                  lldb::offset_t file_offset, lldb::offset_t file_size,
160                  uint32_t log2align, uint32_t flags,
161                  uint32_t target_byte_size /*=1*/)
162     : ModuleChild(module_sp), UserID(sect_id), Flags(flags),
163       m_obj_file(obj_file), m_type(sect_type), m_parent_wp(), m_name(name),
164       m_file_addr(file_addr), m_byte_size(byte_size),
165       m_file_offset(file_offset), m_file_size(file_size),
166       m_log2align(log2align), m_children(), m_fake(false), m_encrypted(false),
167       m_thread_specific(false), m_readable(false), m_writable(false),
168       m_executable(false), m_relocated(false), m_target_byte_size(target_byte_size) {
169   //    printf ("Section::Section(%p): module=%p, sect_id = 0x%16.16" PRIx64 ",
170   //    addr=[0x%16.16" PRIx64 " - 0x%16.16" PRIx64 "), file [0x%16.16" PRIx64 "
171   //    - 0x%16.16" PRIx64 "), flags = 0x%8.8x, name = %s.%s\n",
172   //            this, module_sp.get(), sect_id, file_addr, file_addr +
173   //            byte_size, file_offset, file_offset + file_size, flags,
174   //            parent_section_sp->GetName().GetCString(), name.GetCString());
175   if (parent_section_sp)
176     m_parent_wp = parent_section_sp;
177 }
178 
179 Section::~Section() {
180   //    printf ("Section::~Section(%p)\n", this);
181 }
182 
183 addr_t Section::GetFileAddress() const {
184   SectionSP parent_sp(GetParent());
185   if (parent_sp) {
186     // This section has a parent which means m_file_addr is an offset into the
187     // parent section, so the file address for this section is the file address
188     // of the parent plus the offset
189     return parent_sp->GetFileAddress() + m_file_addr;
190   }
191   // This section has no parent, so m_file_addr is the file base address
192   return m_file_addr;
193 }
194 
195 bool Section::SetFileAddress(lldb::addr_t file_addr) {
196   SectionSP parent_sp(GetParent());
197   if (parent_sp) {
198     if (m_file_addr >= file_addr)
199       return parent_sp->SetFileAddress(m_file_addr - file_addr);
200     return false;
201   } else {
202     // This section has no parent, so m_file_addr is the file base address
203     m_file_addr = file_addr;
204     return true;
205   }
206 }
207 
208 lldb::addr_t Section::GetOffset() const {
209   // This section has a parent which means m_file_addr is an offset.
210   SectionSP parent_sp(GetParent());
211   if (parent_sp)
212     return m_file_addr;
213 
214   // This section has no parent, so there is no offset to be had
215   return 0;
216 }
217 
218 addr_t Section::GetLoadBaseAddress(Target *target) const {
219   addr_t load_base_addr = LLDB_INVALID_ADDRESS;
220   SectionSP parent_sp(GetParent());
221   if (parent_sp) {
222     load_base_addr = parent_sp->GetLoadBaseAddress(target);
223     if (load_base_addr != LLDB_INVALID_ADDRESS)
224       load_base_addr += GetOffset();
225   }
226   if (load_base_addr == LLDB_INVALID_ADDRESS) {
227     load_base_addr = target->GetSectionLoadList().GetSectionLoadAddress(
228         const_cast<Section *>(this)->shared_from_this());
229   }
230   return load_base_addr;
231 }
232 
233 bool Section::ResolveContainedAddress(addr_t offset, Address &so_addr,
234                                       bool allow_section_end) const {
235   const size_t num_children = m_children.GetSize();
236   for (size_t i = 0; i < num_children; i++) {
237     Section *child_section = m_children.GetSectionAtIndex(i).get();
238 
239     addr_t child_offset = child_section->GetOffset();
240     if (child_offset <= offset &&
241         offset - child_offset <
242             child_section->GetByteSize() + (allow_section_end ? 1 : 0))
243       return child_section->ResolveContainedAddress(offset - child_offset,
244                                                     so_addr, allow_section_end);
245   }
246   so_addr.SetOffset(offset);
247   so_addr.SetSection(const_cast<Section *>(this)->shared_from_this());
248 
249 #ifdef LLDB_CONFIGURATION_DEBUG
250   // For debug builds, ensure that there are no orphaned (i.e., moduleless)
251   // sections.
252   assert(GetModule().get());
253 #endif
254   return true;
255 }
256 
257 bool Section::ContainsFileAddress(addr_t vm_addr) const {
258   const addr_t file_addr = GetFileAddress();
259   if (file_addr != LLDB_INVALID_ADDRESS) {
260     if (file_addr <= vm_addr) {
261       const addr_t offset = (vm_addr - file_addr) * m_target_byte_size;
262       return offset < GetByteSize();
263     }
264   }
265   return false;
266 }
267 
268 int Section::Compare(const Section &a, const Section &b) {
269   if (&a == &b)
270     return 0;
271 
272   const ModuleSP a_module_sp = a.GetModule();
273   const ModuleSP b_module_sp = b.GetModule();
274   if (a_module_sp == b_module_sp) {
275     user_id_t a_sect_uid = a.GetID();
276     user_id_t b_sect_uid = b.GetID();
277     if (a_sect_uid < b_sect_uid)
278       return -1;
279     if (a_sect_uid > b_sect_uid)
280       return 1;
281     return 0;
282   } else {
283     // The modules are different, just compare the module pointers
284     if (a_module_sp.get() < b_module_sp.get())
285       return -1;
286     else
287       return 1; // We already know the modules aren't equal
288   }
289 }
290 
291 void Section::Dump(Stream *s, Target *target, uint32_t depth) const {
292   //    s->Printf("%.*p: ", (int)sizeof(void*) * 2, this);
293   s->Indent();
294   s->Printf("0x%8.8" PRIx64 " %-16s ", GetID(), GetTypeAsCString());
295   bool resolved = true;
296   addr_t addr = LLDB_INVALID_ADDRESS;
297 
298   if (GetByteSize() == 0)
299     s->Printf("%39s", "");
300   else {
301     if (target)
302       addr = GetLoadBaseAddress(target);
303 
304     if (addr == LLDB_INVALID_ADDRESS) {
305       if (target)
306         resolved = false;
307       addr = GetFileAddress();
308     }
309 
310     VMRange range(addr, addr + m_byte_size);
311     range.Dump(s, 0);
312   }
313 
314   s->Printf("%c %c%c%c  0x%8.8" PRIx64 " 0x%8.8" PRIx64 " 0x%8.8x ",
315             resolved ? ' ' : '*', m_readable ? 'r' : '-',
316             m_writable ? 'w' : '-', m_executable ? 'x' : '-', m_file_offset,
317             m_file_size, Get());
318 
319   DumpName(s);
320 
321   s->EOL();
322 
323   if (depth > 0)
324     m_children.Dump(s, target, false, depth - 1);
325 }
326 
327 void Section::DumpName(Stream *s) const {
328   SectionSP parent_sp(GetParent());
329   if (parent_sp) {
330     parent_sp->DumpName(s);
331     s->PutChar('.');
332   } else {
333     // The top most section prints the module basename
334     const char *name = NULL;
335     ModuleSP module_sp(GetModule());
336 
337     if (m_obj_file) {
338       const FileSpec &file_spec = m_obj_file->GetFileSpec();
339       name = file_spec.GetFilename().AsCString();
340     }
341     if ((!name || !name[0]) && module_sp)
342       name = module_sp->GetFileSpec().GetFilename().AsCString();
343     if (name && name[0])
344       s->Printf("%s.", name);
345   }
346   m_name.Dump(s);
347 }
348 
349 bool Section::IsDescendant(const Section *section) {
350   if (this == section)
351     return true;
352   SectionSP parent_sp(GetParent());
353   if (parent_sp)
354     return parent_sp->IsDescendant(section);
355   return false;
356 }
357 
358 bool Section::Slide(addr_t slide_amount, bool slide_children) {
359   if (m_file_addr != LLDB_INVALID_ADDRESS) {
360     if (slide_amount == 0)
361       return true;
362 
363     m_file_addr += slide_amount;
364 
365     if (slide_children)
366       m_children.Slide(slide_amount, slide_children);
367 
368     return true;
369   }
370   return false;
371 }
372 
373 //------------------------------------------------------------------
374 /// Get the permissions as OR'ed bits from lldb::Permissions
375 //------------------------------------------------------------------
376 uint32_t Section::GetPermissions() const {
377   uint32_t permissions = 0;
378   if (m_readable)
379     permissions |= ePermissionsReadable;
380   if (m_writable)
381     permissions |= ePermissionsWritable;
382   if (m_executable)
383     permissions |= ePermissionsExecutable;
384   return permissions;
385 }
386 
387 //------------------------------------------------------------------
388 /// Set the permissions using bits OR'ed from lldb::Permissions
389 //------------------------------------------------------------------
390 void Section::SetPermissions(uint32_t permissions) {
391   m_readable = (permissions & ePermissionsReadable) != 0;
392   m_writable = (permissions & ePermissionsWritable) != 0;
393   m_executable = (permissions & ePermissionsExecutable) != 0;
394 }
395 
396 lldb::offset_t Section::GetSectionData(void *dst, lldb::offset_t dst_len,
397                                        lldb::offset_t offset) {
398   if (m_obj_file)
399     return m_obj_file->ReadSectionData(this, offset, dst, dst_len);
400   return 0;
401 }
402 
403 lldb::offset_t Section::GetSectionData(DataExtractor &section_data) {
404   if (m_obj_file)
405     return m_obj_file->ReadSectionData(this, section_data);
406   return 0;
407 }
408 
409 #pragma mark SectionList
410 
411 SectionList::SectionList() : m_sections() {}
412 
413 SectionList::~SectionList() {}
414 
415 SectionList &SectionList::operator=(const SectionList &rhs) {
416   if (this != &rhs)
417     m_sections = rhs.m_sections;
418   return *this;
419 }
420 
421 size_t SectionList::AddSection(const lldb::SectionSP &section_sp) {
422   if (section_sp) {
423     size_t section_index = m_sections.size();
424     m_sections.push_back(section_sp);
425     return section_index;
426   }
427 
428   return std::numeric_limits<size_t>::max();
429 }
430 
431 // Warning, this can be slow as it's removing items from a std::vector.
432 bool SectionList::DeleteSection(size_t idx) {
433   if (idx < m_sections.size()) {
434     m_sections.erase(m_sections.begin() + idx);
435     return true;
436   }
437   return false;
438 }
439 
440 size_t SectionList::FindSectionIndex(const Section *sect) {
441   iterator sect_iter;
442   iterator begin = m_sections.begin();
443   iterator end = m_sections.end();
444   for (sect_iter = begin; sect_iter != end; ++sect_iter) {
445     if (sect_iter->get() == sect) {
446       // The secton was already in this section list
447       return std::distance(begin, sect_iter);
448     }
449   }
450   return UINT32_MAX;
451 }
452 
453 size_t SectionList::AddUniqueSection(const lldb::SectionSP &sect_sp) {
454   size_t sect_idx = FindSectionIndex(sect_sp.get());
455   if (sect_idx == UINT32_MAX) {
456     sect_idx = AddSection(sect_sp);
457   }
458   return sect_idx;
459 }
460 
461 bool SectionList::ReplaceSection(user_id_t sect_id,
462                                  const lldb::SectionSP &sect_sp,
463                                  uint32_t depth) {
464   iterator sect_iter, end = m_sections.end();
465   for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
466     if ((*sect_iter)->GetID() == sect_id) {
467       *sect_iter = sect_sp;
468       return true;
469     } else if (depth > 0) {
470       if ((*sect_iter)
471               ->GetChildren()
472               .ReplaceSection(sect_id, sect_sp, depth - 1))
473         return true;
474     }
475   }
476   return false;
477 }
478 
479 size_t SectionList::GetNumSections(uint32_t depth) const {
480   size_t count = m_sections.size();
481   if (depth > 0) {
482     const_iterator sect_iter, end = m_sections.end();
483     for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
484       count += (*sect_iter)->GetChildren().GetNumSections(depth - 1);
485     }
486   }
487   return count;
488 }
489 
490 SectionSP SectionList::GetSectionAtIndex(size_t idx) const {
491   SectionSP sect_sp;
492   if (idx < m_sections.size())
493     sect_sp = m_sections[idx];
494   return sect_sp;
495 }
496 
497 SectionSP
498 SectionList::FindSectionByName(const ConstString &section_dstr) const {
499   SectionSP sect_sp;
500   // Check if we have a valid section string
501   if (section_dstr && !m_sections.empty()) {
502     const_iterator sect_iter;
503     const_iterator end = m_sections.end();
504     for (sect_iter = m_sections.begin();
505          sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
506       Section *child_section = sect_iter->get();
507       if (child_section) {
508         if (child_section->GetName() == section_dstr) {
509           sect_sp = *sect_iter;
510         } else {
511           sect_sp =
512               child_section->GetChildren().FindSectionByName(section_dstr);
513         }
514       }
515     }
516   }
517   return sect_sp;
518 }
519 
520 SectionSP SectionList::FindSectionByID(user_id_t sect_id) const {
521   SectionSP sect_sp;
522   if (sect_id) {
523     const_iterator sect_iter;
524     const_iterator end = m_sections.end();
525     for (sect_iter = m_sections.begin();
526          sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
527       if ((*sect_iter)->GetID() == sect_id) {
528         sect_sp = *sect_iter;
529         break;
530       } else {
531         sect_sp = (*sect_iter)->GetChildren().FindSectionByID(sect_id);
532       }
533     }
534   }
535   return sect_sp;
536 }
537 
538 SectionSP SectionList::FindSectionByType(SectionType sect_type,
539                                          bool check_children,
540                                          size_t start_idx) const {
541   SectionSP sect_sp;
542   size_t num_sections = m_sections.size();
543   for (size_t idx = start_idx; idx < num_sections; ++idx) {
544     if (m_sections[idx]->GetType() == sect_type) {
545       sect_sp = m_sections[idx];
546       break;
547     } else if (check_children) {
548       sect_sp = m_sections[idx]->GetChildren().FindSectionByType(
549           sect_type, check_children, 0);
550       if (sect_sp)
551         break;
552     }
553   }
554   return sect_sp;
555 }
556 
557 SectionSP SectionList::FindSectionContainingFileAddress(addr_t vm_addr,
558                                                         uint32_t depth) const {
559   SectionSP sect_sp;
560   const_iterator sect_iter;
561   const_iterator end = m_sections.end();
562   for (sect_iter = m_sections.begin();
563        sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
564     Section *sect = sect_iter->get();
565     if (sect->ContainsFileAddress(vm_addr)) {
566       // The file address is in this section. We need to make sure one of our
567       // child sections doesn't contain this address as well as obeying the
568       // depth limit that was passed in.
569       if (depth > 0)
570         sect_sp = sect->GetChildren().FindSectionContainingFileAddress(
571             vm_addr, depth - 1);
572 
573       if (sect_sp.get() == NULL && !sect->IsFake())
574         sect_sp = *sect_iter;
575     }
576   }
577   return sect_sp;
578 }
579 
580 bool SectionList::ContainsSection(user_id_t sect_id) const {
581   return FindSectionByID(sect_id).get() != NULL;
582 }
583 
584 void SectionList::Dump(Stream *s, Target *target, bool show_header,
585                        uint32_t depth) const {
586   bool target_has_loaded_sections =
587       target && !target->GetSectionLoadList().IsEmpty();
588   if (show_header && !m_sections.empty()) {
589     s->Indent();
590     s->Printf("SectID     Type             %s Address                          "
591               "   Perm File Off.  File Size  Flags "
592               "     Section Name\n",
593               target_has_loaded_sections ? "Load" : "File");
594     s->Indent();
595     s->PutCString("---------- ---------------- "
596                   "---------------------------------------  ---- ---------- "
597                   "---------- "
598                   "---------- ----------------------------\n");
599   }
600 
601   const_iterator sect_iter;
602   const_iterator end = m_sections.end();
603   for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
604     (*sect_iter)->Dump(s, target_has_loaded_sections ? target : NULL, depth);
605   }
606 
607   if (show_header && !m_sections.empty())
608     s->IndentLess();
609 }
610 
611 size_t SectionList::Slide(addr_t slide_amount, bool slide_children) {
612   size_t count = 0;
613   const_iterator pos, end = m_sections.end();
614   for (pos = m_sections.begin(); pos != end; ++pos) {
615     if ((*pos)->Slide(slide_amount, slide_children))
616       ++count;
617   }
618   return count;
619 }
620