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"
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"
17 #include "lldb/Utility/Stream.h"
18 #include "lldb/Utility/VMRange.h"
19 
20 #include <inttypes.h>
21 #include <limits>
22 #include <utility>
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 eSectionTypeDWARFDebugLocLists:
81     return "dwarf-loclists";
82   case eSectionTypeDWARFDebugMacInfo:
83     return "dwarf-macinfo";
84   case eSectionTypeDWARFDebugMacro:
85     return "dwarf-macro";
86   case eSectionTypeDWARFDebugPubNames:
87     return "dwarf-pubnames";
88   case eSectionTypeDWARFDebugPubTypes:
89     return "dwarf-pubtypes";
90   case eSectionTypeDWARFDebugRanges:
91     return "dwarf-ranges";
92   case eSectionTypeDWARFDebugRngLists:
93     return "dwarf-rnglists";
94   case eSectionTypeDWARFDebugStr:
95     return "dwarf-str";
96   case eSectionTypeDWARFDebugStrOffsets:
97     return "dwarf-str-offsets";
98   case eSectionTypeDWARFDebugTypes:
99     return "dwarf-types";
100   case eSectionTypeDWARFDebugNames:
101     return "dwarf-names";
102   case eSectionTypeELFSymbolTable:
103     return "elf-symbol-table";
104   case eSectionTypeELFDynamicSymbols:
105     return "elf-dynamic-symbols";
106   case eSectionTypeELFRelocationEntries:
107     return "elf-relocation-entries";
108   case eSectionTypeELFDynamicLinkInfo:
109     return "elf-dynamic-link-info";
110   case eSectionTypeDWARFAppleNames:
111     return "apple-names";
112   case eSectionTypeDWARFAppleTypes:
113     return "apple-types";
114   case eSectionTypeDWARFAppleNamespaces:
115     return "apple-namespaces";
116   case eSectionTypeDWARFAppleObjC:
117     return "apple-objc";
118   case eSectionTypeEHFrame:
119     return "eh-frame";
120   case eSectionTypeARMexidx:
121     return "ARM.exidx";
122   case eSectionTypeARMextab:
123     return "ARM.extab";
124   case eSectionTypeCompactUnwind:
125     return "compact-unwind";
126   case eSectionTypeGoSymtab:
127     return "go-symtab";
128   case eSectionTypeAbsoluteAddress:
129     return "absolute";
130   case eSectionTypeDWARFGNUDebugAltLink:
131     return "dwarf-gnu-debugaltlink";
132   case eSectionTypeOther:
133     return "regular";
134   }
135   return "unknown";
136 }
137 
138 Section::Section(const ModuleSP &module_sp, ObjectFile *obj_file,
139                  user_id_t sect_id, const ConstString &name,
140                  SectionType sect_type, addr_t file_addr, addr_t byte_size,
141                  lldb::offset_t file_offset, lldb::offset_t file_size,
142                  uint32_t log2align, uint32_t flags,
143                  uint32_t target_byte_size /*=1*/)
144     : ModuleChild(module_sp), UserID(sect_id), Flags(flags),
145       m_obj_file(obj_file), m_type(sect_type), m_parent_wp(), m_name(name),
146       m_file_addr(file_addr), m_byte_size(byte_size),
147       m_file_offset(file_offset), m_file_size(file_size),
148       m_log2align(log2align), m_children(), m_fake(false), m_encrypted(false),
149       m_thread_specific(false), m_readable(false), m_writable(false),
150       m_executable(false), m_relocated(false), m_target_byte_size(target_byte_size) {
151   //    printf ("Section::Section(%p): module=%p, sect_id = 0x%16.16" PRIx64 ",
152   //    addr=[0x%16.16" PRIx64 " - 0x%16.16" PRIx64 "), file [0x%16.16" PRIx64 "
153   //    - 0x%16.16" PRIx64 "), flags = 0x%8.8x, name = %s\n",
154   //            this, module_sp.get(), sect_id, file_addr, file_addr +
155   //            byte_size, file_offset, file_offset + file_size, flags,
156   //            name.GetCString());
157 }
158 
159 Section::Section(const lldb::SectionSP &parent_section_sp,
160                  const ModuleSP &module_sp, ObjectFile *obj_file,
161                  user_id_t sect_id, const ConstString &name,
162                  SectionType sect_type, addr_t file_addr, addr_t byte_size,
163                  lldb::offset_t file_offset, lldb::offset_t file_size,
164                  uint32_t log2align, uint32_t flags,
165                  uint32_t target_byte_size /*=1*/)
166     : ModuleChild(module_sp), UserID(sect_id), Flags(flags),
167       m_obj_file(obj_file), m_type(sect_type), m_parent_wp(), m_name(name),
168       m_file_addr(file_addr), m_byte_size(byte_size),
169       m_file_offset(file_offset), m_file_size(file_size),
170       m_log2align(log2align), m_children(), m_fake(false), m_encrypted(false),
171       m_thread_specific(false), m_readable(false), m_writable(false),
172       m_executable(false), m_relocated(false), m_target_byte_size(target_byte_size) {
173   //    printf ("Section::Section(%p): module=%p, sect_id = 0x%16.16" PRIx64 ",
174   //    addr=[0x%16.16" PRIx64 " - 0x%16.16" PRIx64 "), file [0x%16.16" PRIx64 "
175   //    - 0x%16.16" PRIx64 "), flags = 0x%8.8x, name = %s.%s\n",
176   //            this, module_sp.get(), sect_id, file_addr, file_addr +
177   //            byte_size, file_offset, file_offset + file_size, flags,
178   //            parent_section_sp->GetName().GetCString(), name.GetCString());
179   if (parent_section_sp)
180     m_parent_wp = parent_section_sp;
181 }
182 
183 Section::~Section() {
184   //    printf ("Section::~Section(%p)\n", this);
185 }
186 
187 addr_t Section::GetFileAddress() const {
188   SectionSP parent_sp(GetParent());
189   if (parent_sp) {
190     // This section has a parent which means m_file_addr is an offset into the
191     // parent section, so the file address for this section is the file address
192     // of the parent plus the offset
193     return parent_sp->GetFileAddress() + m_file_addr;
194   }
195   // This section has no parent, so m_file_addr is the file base address
196   return m_file_addr;
197 }
198 
199 bool Section::SetFileAddress(lldb::addr_t file_addr) {
200   SectionSP parent_sp(GetParent());
201   if (parent_sp) {
202     if (m_file_addr >= file_addr)
203       return parent_sp->SetFileAddress(m_file_addr - file_addr);
204     return false;
205   } else {
206     // This section has no parent, so m_file_addr is the file base address
207     m_file_addr = file_addr;
208     return true;
209   }
210 }
211 
212 lldb::addr_t Section::GetOffset() const {
213   // This section has a parent which means m_file_addr is an offset.
214   SectionSP parent_sp(GetParent());
215   if (parent_sp)
216     return m_file_addr;
217 
218   // This section has no parent, so there is no offset to be had
219   return 0;
220 }
221 
222 addr_t Section::GetLoadBaseAddress(Target *target) const {
223   addr_t load_base_addr = LLDB_INVALID_ADDRESS;
224   SectionSP parent_sp(GetParent());
225   if (parent_sp) {
226     load_base_addr = parent_sp->GetLoadBaseAddress(target);
227     if (load_base_addr != LLDB_INVALID_ADDRESS)
228       load_base_addr += GetOffset();
229   }
230   if (load_base_addr == LLDB_INVALID_ADDRESS) {
231     load_base_addr = target->GetSectionLoadList().GetSectionLoadAddress(
232         const_cast<Section *>(this)->shared_from_this());
233   }
234   return load_base_addr;
235 }
236 
237 bool Section::ResolveContainedAddress(addr_t offset, Address &so_addr,
238                                       bool allow_section_end) const {
239   const size_t num_children = m_children.GetSize();
240   for (size_t i = 0; i < num_children; i++) {
241     Section *child_section = m_children.GetSectionAtIndex(i).get();
242 
243     addr_t child_offset = child_section->GetOffset();
244     if (child_offset <= offset &&
245         offset - child_offset <
246             child_section->GetByteSize() + (allow_section_end ? 1 : 0))
247       return child_section->ResolveContainedAddress(offset - child_offset,
248                                                     so_addr, allow_section_end);
249   }
250   so_addr.SetOffset(offset);
251   so_addr.SetSection(const_cast<Section *>(this)->shared_from_this());
252 
253 #ifdef LLDB_CONFIGURATION_DEBUG
254   // For debug builds, ensure that there are no orphaned (i.e., moduleless)
255   // sections.
256   assert(GetModule().get());
257 #endif
258   return true;
259 }
260 
261 bool Section::ContainsFileAddress(addr_t vm_addr) const {
262   const addr_t file_addr = GetFileAddress();
263   if (file_addr != LLDB_INVALID_ADDRESS) {
264     if (file_addr <= vm_addr) {
265       const addr_t offset = (vm_addr - file_addr) * m_target_byte_size;
266       return offset < GetByteSize();
267     }
268   }
269   return false;
270 }
271 
272 int Section::Compare(const Section &a, const Section &b) {
273   if (&a == &b)
274     return 0;
275 
276   const ModuleSP a_module_sp = a.GetModule();
277   const ModuleSP b_module_sp = b.GetModule();
278   if (a_module_sp == b_module_sp) {
279     user_id_t a_sect_uid = a.GetID();
280     user_id_t b_sect_uid = b.GetID();
281     if (a_sect_uid < b_sect_uid)
282       return -1;
283     if (a_sect_uid > b_sect_uid)
284       return 1;
285     return 0;
286   } else {
287     // The modules are different, just compare the module pointers
288     if (a_module_sp.get() < b_module_sp.get())
289       return -1;
290     else
291       return 1; // We already know the modules aren't equal
292   }
293 }
294 
295 void Section::Dump(Stream *s, Target *target, uint32_t depth) const {
296   //    s->Printf("%.*p: ", (int)sizeof(void*) * 2, this);
297   s->Indent();
298   s->Printf("0x%8.8" PRIx64 " %-16s ", GetID(), GetTypeAsCString());
299   bool resolved = true;
300   addr_t addr = LLDB_INVALID_ADDRESS;
301 
302   if (GetByteSize() == 0)
303     s->Printf("%39s", "");
304   else {
305     if (target)
306       addr = GetLoadBaseAddress(target);
307 
308     if (addr == LLDB_INVALID_ADDRESS) {
309       if (target)
310         resolved = false;
311       addr = GetFileAddress();
312     }
313 
314     VMRange range(addr, addr + m_byte_size);
315     range.Dump(s, 0);
316   }
317 
318   s->Printf("%c %c%c%c  0x%8.8" PRIx64 " 0x%8.8" PRIx64 " 0x%8.8x ",
319             resolved ? ' ' : '*', m_readable ? 'r' : '-',
320             m_writable ? 'w' : '-', m_executable ? 'x' : '-', m_file_offset,
321             m_file_size, Get());
322 
323   DumpName(s);
324 
325   s->EOL();
326 
327   if (depth > 0)
328     m_children.Dump(s, target, false, depth - 1);
329 }
330 
331 void Section::DumpName(Stream *s) const {
332   SectionSP parent_sp(GetParent());
333   if (parent_sp) {
334     parent_sp->DumpName(s);
335     s->PutChar('.');
336   } else {
337     // The top most section prints the module basename
338     const char *name = NULL;
339     ModuleSP module_sp(GetModule());
340 
341     if (m_obj_file) {
342       const FileSpec &file_spec = m_obj_file->GetFileSpec();
343       name = file_spec.GetFilename().AsCString();
344     }
345     if ((!name || !name[0]) && module_sp)
346       name = module_sp->GetFileSpec().GetFilename().AsCString();
347     if (name && name[0])
348       s->Printf("%s.", name);
349   }
350   m_name.Dump(s);
351 }
352 
353 bool Section::IsDescendant(const Section *section) {
354   if (this == section)
355     return true;
356   SectionSP parent_sp(GetParent());
357   if (parent_sp)
358     return parent_sp->IsDescendant(section);
359   return false;
360 }
361 
362 bool Section::Slide(addr_t slide_amount, bool slide_children) {
363   if (m_file_addr != LLDB_INVALID_ADDRESS) {
364     if (slide_amount == 0)
365       return true;
366 
367     m_file_addr += slide_amount;
368 
369     if (slide_children)
370       m_children.Slide(slide_amount, slide_children);
371 
372     return true;
373   }
374   return false;
375 }
376 
377 //------------------------------------------------------------------
378 /// Get the permissions as OR'ed bits from lldb::Permissions
379 //------------------------------------------------------------------
380 uint32_t Section::GetPermissions() const {
381   uint32_t permissions = 0;
382   if (m_readable)
383     permissions |= ePermissionsReadable;
384   if (m_writable)
385     permissions |= ePermissionsWritable;
386   if (m_executable)
387     permissions |= ePermissionsExecutable;
388   return permissions;
389 }
390 
391 //------------------------------------------------------------------
392 /// Set the permissions using bits OR'ed from lldb::Permissions
393 //------------------------------------------------------------------
394 void Section::SetPermissions(uint32_t permissions) {
395   m_readable = (permissions & ePermissionsReadable) != 0;
396   m_writable = (permissions & ePermissionsWritable) != 0;
397   m_executable = (permissions & ePermissionsExecutable) != 0;
398 }
399 
400 lldb::offset_t Section::GetSectionData(void *dst, lldb::offset_t dst_len,
401                                        lldb::offset_t offset) {
402   if (m_obj_file)
403     return m_obj_file->ReadSectionData(this, offset, dst, dst_len);
404   return 0;
405 }
406 
407 lldb::offset_t Section::GetSectionData(DataExtractor &section_data) {
408   if (m_obj_file)
409     return m_obj_file->ReadSectionData(this, section_data);
410   return 0;
411 }
412 
413 #pragma mark SectionList
414 
415 SectionList::SectionList() : m_sections() {}
416 
417 SectionList::~SectionList() {}
418 
419 SectionList &SectionList::operator=(const SectionList &rhs) {
420   if (this != &rhs)
421     m_sections = rhs.m_sections;
422   return *this;
423 }
424 
425 size_t SectionList::AddSection(const lldb::SectionSP &section_sp) {
426   if (section_sp) {
427     size_t section_index = m_sections.size();
428     m_sections.push_back(section_sp);
429     return section_index;
430   }
431 
432   return std::numeric_limits<size_t>::max();
433 }
434 
435 // Warning, this can be slow as it's removing items from a std::vector.
436 bool SectionList::DeleteSection(size_t idx) {
437   if (idx < m_sections.size()) {
438     m_sections.erase(m_sections.begin() + idx);
439     return true;
440   }
441   return false;
442 }
443 
444 size_t SectionList::FindSectionIndex(const Section *sect) {
445   iterator sect_iter;
446   iterator begin = m_sections.begin();
447   iterator end = m_sections.end();
448   for (sect_iter = begin; sect_iter != end; ++sect_iter) {
449     if (sect_iter->get() == sect) {
450       // The secton was already in this section list
451       return std::distance(begin, sect_iter);
452     }
453   }
454   return UINT32_MAX;
455 }
456 
457 size_t SectionList::AddUniqueSection(const lldb::SectionSP &sect_sp) {
458   size_t sect_idx = FindSectionIndex(sect_sp.get());
459   if (sect_idx == UINT32_MAX) {
460     sect_idx = AddSection(sect_sp);
461   }
462   return sect_idx;
463 }
464 
465 bool SectionList::ReplaceSection(user_id_t sect_id,
466                                  const lldb::SectionSP &sect_sp,
467                                  uint32_t depth) {
468   iterator sect_iter, end = m_sections.end();
469   for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
470     if ((*sect_iter)->GetID() == sect_id) {
471       *sect_iter = sect_sp;
472       return true;
473     } else if (depth > 0) {
474       if ((*sect_iter)
475               ->GetChildren()
476               .ReplaceSection(sect_id, sect_sp, depth - 1))
477         return true;
478     }
479   }
480   return false;
481 }
482 
483 size_t SectionList::GetNumSections(uint32_t depth) const {
484   size_t count = m_sections.size();
485   if (depth > 0) {
486     const_iterator sect_iter, end = m_sections.end();
487     for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
488       count += (*sect_iter)->GetChildren().GetNumSections(depth - 1);
489     }
490   }
491   return count;
492 }
493 
494 SectionSP SectionList::GetSectionAtIndex(size_t idx) const {
495   SectionSP sect_sp;
496   if (idx < m_sections.size())
497     sect_sp = m_sections[idx];
498   return sect_sp;
499 }
500 
501 SectionSP
502 SectionList::FindSectionByName(const ConstString &section_dstr) const {
503   SectionSP sect_sp;
504   // Check if we have a valid section string
505   if (section_dstr && !m_sections.empty()) {
506     const_iterator sect_iter;
507     const_iterator end = m_sections.end();
508     for (sect_iter = m_sections.begin();
509          sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
510       Section *child_section = sect_iter->get();
511       if (child_section) {
512         if (child_section->GetName() == section_dstr) {
513           sect_sp = *sect_iter;
514         } else {
515           sect_sp =
516               child_section->GetChildren().FindSectionByName(section_dstr);
517         }
518       }
519     }
520   }
521   return sect_sp;
522 }
523 
524 SectionSP SectionList::FindSectionByID(user_id_t sect_id) const {
525   SectionSP sect_sp;
526   if (sect_id) {
527     const_iterator sect_iter;
528     const_iterator end = m_sections.end();
529     for (sect_iter = m_sections.begin();
530          sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
531       if ((*sect_iter)->GetID() == sect_id) {
532         sect_sp = *sect_iter;
533         break;
534       } else {
535         sect_sp = (*sect_iter)->GetChildren().FindSectionByID(sect_id);
536       }
537     }
538   }
539   return sect_sp;
540 }
541 
542 SectionSP SectionList::FindSectionByType(SectionType sect_type,
543                                          bool check_children,
544                                          size_t start_idx) const {
545   SectionSP sect_sp;
546   size_t num_sections = m_sections.size();
547   for (size_t idx = start_idx; idx < num_sections; ++idx) {
548     if (m_sections[idx]->GetType() == sect_type) {
549       sect_sp = m_sections[idx];
550       break;
551     } else if (check_children) {
552       sect_sp = m_sections[idx]->GetChildren().FindSectionByType(
553           sect_type, check_children, 0);
554       if (sect_sp)
555         break;
556     }
557   }
558   return sect_sp;
559 }
560 
561 SectionSP SectionList::FindSectionContainingFileAddress(addr_t vm_addr,
562                                                         uint32_t depth) const {
563   SectionSP sect_sp;
564   const_iterator sect_iter;
565   const_iterator end = m_sections.end();
566   for (sect_iter = m_sections.begin();
567        sect_iter != end && sect_sp.get() == NULL; ++sect_iter) {
568     Section *sect = sect_iter->get();
569     if (sect->ContainsFileAddress(vm_addr)) {
570       // The file address is in this section. We need to make sure one of our
571       // child sections doesn't contain this address as well as obeying the
572       // depth limit that was passed in.
573       if (depth > 0)
574         sect_sp = sect->GetChildren().FindSectionContainingFileAddress(
575             vm_addr, depth - 1);
576 
577       if (sect_sp.get() == NULL && !sect->IsFake())
578         sect_sp = *sect_iter;
579     }
580   }
581   return sect_sp;
582 }
583 
584 bool SectionList::ContainsSection(user_id_t sect_id) const {
585   return FindSectionByID(sect_id).get() != NULL;
586 }
587 
588 void SectionList::Dump(Stream *s, Target *target, bool show_header,
589                        uint32_t depth) const {
590   bool target_has_loaded_sections =
591       target && !target->GetSectionLoadList().IsEmpty();
592   if (show_header && !m_sections.empty()) {
593     s->Indent();
594     s->Printf("SectID     Type             %s Address                          "
595               "   Perm File Off.  File Size  Flags "
596               "     Section Name\n",
597               target_has_loaded_sections ? "Load" : "File");
598     s->Indent();
599     s->PutCString("---------- ---------------- "
600                   "---------------------------------------  ---- ---------- "
601                   "---------- "
602                   "---------- ----------------------------\n");
603   }
604 
605   const_iterator sect_iter;
606   const_iterator end = m_sections.end();
607   for (sect_iter = m_sections.begin(); sect_iter != end; ++sect_iter) {
608     (*sect_iter)->Dump(s, target_has_loaded_sections ? target : NULL, depth);
609   }
610 
611   if (show_header && !m_sections.empty())
612     s->IndentLess();
613 }
614 
615 size_t SectionList::Slide(addr_t slide_amount, bool slide_children) {
616   size_t count = 0;
617   const_iterator pos, end = m_sections.end();
618   for (pos = m_sections.begin(); pos != end; ++pos) {
619     if ((*pos)->Slide(slide_amount, slide_children))
620       ++count;
621   }
622   return count;
623 }
624