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