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1 // Copyright (c) 2010 Google Inc.
2 // All rights reserved.
3 //
4 // Redistribution and use in source and binary forms, with or without
5 // modification, are permitted provided that the following conditions are
6 // met:
7 //
8 //     * Redistributions of source code must retain the above copyright
9 // notice, this list of conditions and the following disclaimer.
10 //     * Redistributions in binary form must reproduce the above
11 // copyright notice, this list of conditions and the following disclaimer
12 // in the documentation and/or other materials provided with the
13 // distribution.
14 //     * Neither the name of Google Inc. nor the names of its
15 // contributors may be used to endorse or promote products derived from
16 // this software without specific prior written permission.
17 //
18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 
30 // minidump.h: A minidump reader.
31 //
32 // The basic structure of this module tracks the structure of the minidump
33 // file itself.  At the top level, a minidump file is represented by a
34 // Minidump object.  Like most other classes in this module, Minidump
35 // provides a Read method that initializes the object with information from
36 // the file.  Most of the classes in this file are wrappers around the
37 // "raw" structures found in the minidump file itself, and defined in
38 // minidump_format.h.  For example, each thread is represented by a
39 // MinidumpThread object, whose parameters are specified in an MDRawThread
40 // structure.  A properly byte-swapped MDRawThread can be obtained from a
41 // MinidumpThread easily by calling its thread() method.
42 //
43 // Most of the module lazily reads only the portion of the minidump file
44 // necessary to fulfill the user's request.  Calling Minidump::Read
45 // only reads the minidump's directory.  The thread list is not read until
46 // it is needed, and even once it's read, the memory regions for each
47 // thread's stack aren't read until they're needed.  This strategy avoids
48 // unnecessary file input, and allocating memory for data in which the user
49 // has no interest.  Note that although memory allocations for a typical
50 // minidump file are not particularly large, it is possible for legitimate
51 // minidumps to be sizable.  A full-memory minidump, for example, contains
52 // a snapshot of the entire mapped memory space.  Even a normal minidump,
53 // with stack memory only, can be large if, for example, the dump was
54 // generated in response to a crash that occurred due to an infinite-
55 // recursion bug that caused the stack's limits to be exceeded.  Finally,
56 // some users of this library will unfortunately find themselves in the
57 // position of having to process potentially-hostile minidumps that might
58 // attempt to cause problems by forcing the minidump processor to over-
59 // allocate memory.
60 //
61 // Memory management in this module is based on a strict
62 // you-don't-own-anything policy.  The only object owned by the user is
63 // the top-level Minidump object, the creation and destruction of which
64 // must be the user's own responsibility.  All other objects obtained
65 // through interaction with this module are ultimately owned by the
66 // Minidump object, and will be freed upon the Minidump object's destruction.
67 // Because memory regions can potentially involve large allocations, a
68 // FreeMemory method is provided by MinidumpMemoryRegion, allowing the user
69 // to release data when it is no longer needed.  Use of this method is
70 // optional but recommended.  If freed data is later required, it will
71 // be read back in from the minidump file again.
72 //
73 // There is one exception to this memory management policy:
74 // Minidump::ReadString will return a string object to the user, and the user
75 // is responsible for its deletion.
76 //
77 // Author: Mark Mentovai
78 
79 #ifndef GOOGLE_BREAKPAD_PROCESSOR_MINIDUMP_H__
80 #define GOOGLE_BREAKPAD_PROCESSOR_MINIDUMP_H__
81 
82 #include <stdint.h>
83 
84 #ifndef _WIN32
85 #include <unistd.h>
86 #endif
87 
88 #include <iostream>
89 #include <map>
90 #include <string>
91 #include <vector>
92 
93 #include "common/basictypes.h"
94 #include "common/using_std_string.h"
95 #include "google_breakpad/processor/code_module.h"
96 #include "google_breakpad/processor/code_modules.h"
97 #include "google_breakpad/processor/dump_context.h"
98 #include "google_breakpad/processor/dump_object.h"
99 #include "google_breakpad/processor/memory_region.h"
100 #include "google_breakpad/processor/proc_maps_linux.h"
101 
102 
103 namespace google_breakpad {
104 
105 
106 using std::map;
107 using std::vector;
108 
109 
110 class Minidump;
111 template<typename AddressType, typename EntryType> class RangeMap;
112 
113 
114 // MinidumpObject is the base of all Minidump* objects except for Minidump
115 // itself.
116 class MinidumpObject : public DumpObject {
117  public:
~MinidumpObject()118   virtual ~MinidumpObject() {}
119 
120  protected:
121   explicit MinidumpObject(Minidump* minidump);
122 
123   // Refers to the Minidump object that is the ultimate parent of this
124   // Some MinidumpObjects are owned by other MinidumpObjects, but at the
125   // root of the ownership tree is always a Minidump.  The Minidump object
126   // is kept here for access to its seeking and reading facilities, and
127   // for access to data about the minidump file itself, such as whether
128   // it should be byte-swapped.
129   Minidump* minidump_;
130 };
131 
132 
133 // This class exists primarily to provide a virtual destructor in a base
134 // class common to all objects that might be stored in
135 // Minidump::mStreamObjects.  Some object types will never be stored in
136 // Minidump::mStreamObjects, but are represented as streams and adhere to the
137 // same interface, and may be derived from this class.
138 class MinidumpStream : public MinidumpObject {
139  public:
~MinidumpStream()140   virtual ~MinidumpStream() {}
141 
142  protected:
143   explicit MinidumpStream(Minidump* minidump);
144 
145  private:
146   // Populate (and validate) the MinidumpStream.  minidump_ is expected
147   // to be positioned at the beginning of the stream, so that the next
148   // read from the minidump will be at the beginning of the stream.
149   // expected_size should be set to the stream's length as contained in
150   // the MDRawDirectory record or other identifying record.  A class
151   // that implements MinidumpStream can compare expected_size to a
152   // known size as an integrity check.
153   virtual bool Read(uint32_t expected_size) = 0;
154 
155   DISALLOW_COPY_AND_ASSIGN(MinidumpStream);
156 };
157 
158 
159 // MinidumpContext carries a CPU-specific MDRawContext structure, which
160 // contains CPU context such as register states.  Each thread has its
161 // own context, and the exception record, if present, also has its own
162 // context.  Note that if the exception record is present, the context it
163 // refers to is probably what the user wants to use for the exception
164 // thread, instead of that thread's own context.  The exception thread's
165 // context (as opposed to the exception record's context) will contain
166 // context for the exception handler (which performs minidump generation),
167 // and not the context that caused the exception (which is probably what the
168 // user wants).
169 class MinidumpContext : public DumpContext {
170  public:
171   virtual ~MinidumpContext();
172 
173  protected:
174   explicit MinidumpContext(Minidump* minidump);
175 
176  private:
177   friend class MinidumpThread;
178   friend class MinidumpException;
179 
180   bool Read(uint32_t expected_size);
181 
182   // If the minidump contains a SYSTEM_INFO_STREAM, makes sure that the
183   // system info stream gives an appropriate CPU type matching the context
184   // CPU type in context_cpu_type.  Returns false if the CPU type does not
185   // match.  Returns true if the CPU type matches or if the minidump does
186   // not contain a system info stream.
187   bool CheckAgainstSystemInfo(uint32_t context_cpu_type);
188 
189   // Refers to the Minidump object that is the ultimate parent of this
190   // Some MinidumpObjects are owned by other MinidumpObjects, but at the
191   // root of the ownership tree is always a Minidump.  The Minidump object
192   // is kept here for access to its seeking and reading facilities, and
193   // for access to data about the minidump file itself, such as whether
194   // it should be byte-swapped.
195   Minidump* minidump_;
196 
197   DISALLOW_COPY_AND_ASSIGN(MinidumpContext);
198 };
199 
200 
201 // MinidumpMemoryRegion does not wrap any MDRaw structure, and only contains
202 // a reference to an MDMemoryDescriptor.  This object is intended to wrap
203 // portions of a minidump file that contain memory dumps.  In normal
204 // minidumps, each MinidumpThread owns a MinidumpMemoryRegion corresponding
205 // to the thread's stack memory.  MinidumpMemoryList also gives access to
206 // memory regions in its list as MinidumpMemoryRegions.  This class
207 // adheres to MemoryRegion so that it may be used as a data provider to
208 // the Stackwalker family of classes.
209 class MinidumpMemoryRegion : public MinidumpObject,
210                              public MemoryRegion {
211  public:
212   virtual ~MinidumpMemoryRegion();
213 
set_max_bytes(uint32_t max_bytes)214   static void set_max_bytes(uint32_t max_bytes) { max_bytes_ = max_bytes; }
max_bytes()215   static uint32_t max_bytes() { return max_bytes_; }
216 
217   // Returns a pointer to the base of the memory region.  Returns the
218   // cached value if available, otherwise, reads the minidump file and
219   // caches the memory region.
220   const uint8_t* GetMemory() const;
221 
222   // The address of the base of the memory region.
223   uint64_t GetBase() const;
224 
225   // The size, in bytes, of the memory region.
226   uint32_t GetSize() const;
227 
228   // Frees the cached memory region, if cached.
229   void FreeMemory();
230 
231   // Obtains the value of memory at the pointer specified by address.
232   bool GetMemoryAtAddress(uint64_t address, uint8_t*  value) const;
233   bool GetMemoryAtAddress(uint64_t address, uint16_t* value) const;
234   bool GetMemoryAtAddress(uint64_t address, uint32_t* value) const;
235   bool GetMemoryAtAddress(uint64_t address, uint64_t* value) const;
236 
237   // Print a human-readable representation of the object to stdout.
238   void Print() const;
239   void SetPrintMode(bool hexdump, unsigned int width);
240 
241  protected:
242   explicit MinidumpMemoryRegion(Minidump* minidump);
243 
244  private:
245   friend class MinidumpThread;
246   friend class MinidumpMemoryList;
247 
248   // Identify the base address and size of the memory region, and the
249   // location it may be found in the minidump file.
250   void SetDescriptor(MDMemoryDescriptor* descriptor);
251 
252   // Implementation for GetMemoryAtAddress
253   template<typename T> bool GetMemoryAtAddressInternal(uint64_t address,
254                                                        T*        value) const;
255 
256   // Knobs for controlling display of memory printing.
257   bool hexdump_;
258   unsigned int hexdump_width_;
259 
260   // The largest memory region that will be read from a minidump.
261   static uint32_t max_bytes_;
262 
263   // Base address and size of the memory region, and its position in the
264   // minidump file.
265   MDMemoryDescriptor* descriptor_;
266 
267   // Cached memory.
268   mutable vector<uint8_t>* memory_;
269 };
270 
271 
272 // MinidumpThread contains information about a thread of execution,
273 // including a snapshot of the thread's stack and CPU context.  For
274 // the thread that caused an exception, the context carried by
275 // MinidumpException is probably desired instead of the CPU context
276 // provided here.
277 // Note that a MinidumpThread may be valid() even if it does not
278 // contain a memory region or context.
279 class MinidumpThread : public MinidumpObject {
280  public:
281   virtual ~MinidumpThread();
282 
thread()283   const MDRawThread* thread() const { return valid_ ? &thread_ : NULL; }
284   // GetMemory may return NULL even if the MinidumpThread is valid,
285   // if the thread memory cannot be read.
286   virtual MinidumpMemoryRegion* GetMemory();
287   // GetContext may return NULL even if the MinidumpThread is valid.
288   virtual MinidumpContext* GetContext();
289 
290   // The thread ID is used to determine if a thread is the exception thread,
291   // so a special getter is provided to retrieve this data from the
292   // MDRawThread structure.  Returns false if the thread ID cannot be
293   // determined.
294   virtual bool GetThreadID(uint32_t *thread_id) const;
295 
296   // Print a human-readable representation of the object to stdout.
297   void Print();
298 
299   // Returns the start address of the thread stack memory region.  Returns 0 if
300   // MinidumpThread is invalid.  Note that this method can be called even when
301   // the thread memory cannot be read and GetMemory returns NULL.
302   virtual uint64_t GetStartOfStackMemoryRange() const;
303 
304  protected:
305   explicit MinidumpThread(Minidump* minidump);
306 
307  private:
308   // These objects are managed by MinidumpThreadList.
309   friend class MinidumpThreadList;
310 
311   // This works like MinidumpStream::Read, but is driven by
312   // MinidumpThreadList.  No size checking is done, because
313   // MinidumpThreadList handles that directly.
314   bool Read();
315 
316   MDRawThread           thread_;
317   MinidumpMemoryRegion* memory_;
318   MinidumpContext*      context_;
319 };
320 
321 
322 // MinidumpThreadList contains all of the threads (as MinidumpThreads) in
323 // a process.
324 class MinidumpThreadList : public MinidumpStream {
325  public:
326   virtual ~MinidumpThreadList();
327 
set_max_threads(uint32_t max_threads)328   static void set_max_threads(uint32_t max_threads) {
329     max_threads_ = max_threads;
330   }
max_threads()331   static uint32_t max_threads() { return max_threads_; }
332 
thread_count()333   virtual unsigned int thread_count() const {
334     return valid_ ? thread_count_ : 0;
335   }
336 
337   // Sequential access to threads.
338   virtual MinidumpThread* GetThreadAtIndex(unsigned int index) const;
339 
340   // Random access to threads.
341   MinidumpThread* GetThreadByID(uint32_t thread_id);
342 
343   // Print a human-readable representation of the object to stdout.
344   void Print();
345 
346  protected:
347   explicit MinidumpThreadList(Minidump* aMinidump);
348 
349  private:
350   friend class Minidump;
351 
352   typedef map<uint32_t, MinidumpThread*> IDToThreadMap;
353   typedef vector<MinidumpThread> MinidumpThreads;
354 
355   static const uint32_t kStreamType = MD_THREAD_LIST_STREAM;
356 
357   bool Read(uint32_t aExpectedSize) override;
358 
359   // The largest number of threads that will be read from a minidump.  The
360   // default is 256.
361   static uint32_t max_threads_;
362 
363   // Access to threads using the thread ID as the key.
364   IDToThreadMap    id_to_thread_map_;
365 
366   // The list of threads.
367   MinidumpThreads* threads_;
368   uint32_t        thread_count_;
369 
370   DISALLOW_COPY_AND_ASSIGN(MinidumpThreadList);
371 };
372 
373 
374 // MinidumpModule wraps MDRawModule, which contains information about loaded
375 // code modules.  Access is provided to various data referenced indirectly
376 // by MDRawModule, such as the module's name and a specification for where
377 // to locate debugging information for the module.
378 class MinidumpModule : public MinidumpObject,
379                        public CodeModule {
380  public:
381   virtual ~MinidumpModule();
382 
set_max_cv_bytes(uint32_t max_cv_bytes)383   static void set_max_cv_bytes(uint32_t max_cv_bytes) {
384     max_cv_bytes_ = max_cv_bytes;
385   }
max_cv_bytes()386   static uint32_t max_cv_bytes() { return max_cv_bytes_; }
387 
set_max_misc_bytes(uint32_t max_misc_bytes)388   static void set_max_misc_bytes(uint32_t max_misc_bytes) {
389     max_misc_bytes_ = max_misc_bytes;
390   }
max_misc_bytes()391   static uint32_t max_misc_bytes() { return max_misc_bytes_; }
392 
module()393   const MDRawModule* module() const { return valid_ ? &module_ : NULL; }
394 
395   // CodeModule implementation
base_address()396   virtual uint64_t base_address() const {
397     return valid_ ? module_.base_of_image : static_cast<uint64_t>(-1);
398   }
size()399   virtual uint64_t size() const { return valid_ ? module_.size_of_image : 0; }
400   virtual string code_file() const;
401   virtual string code_identifier() const;
402   virtual string debug_file() const;
403   virtual string debug_identifier() const;
404   virtual string version() const;
405   virtual CodeModule* Copy() const;
is_unloaded()406   virtual bool is_unloaded() const { return false; }
407 
408   // Getter and setter for shrink_down_delta.  This is used when the address
409   // range for a module is shrunk down due to address range conflicts with
410   // other modules.  The base_address and size fields are not updated and they
411   // should always reflect the original values (reported in the minidump).
412   virtual uint64_t shrink_down_delta() const;
413   virtual void SetShrinkDownDelta(uint64_t shrink_down_delta);
414 
415   // The CodeView record, which contains information to locate the module's
416   // debugging information (pdb).  This is returned as uint8_t* because
417   // the data can be of types MDCVInfoPDB20* or MDCVInfoPDB70*, or it may be
418   // of a type unknown to Breakpad, in which case the raw data will still be
419   // returned but no byte-swapping will have been performed.  Check the
420   // record's signature in the first four bytes to differentiate between
421   // the various types.  Current toolchains generate modules which carry
422   // MDCVInfoPDB70 by default.  Returns a pointer to the CodeView record on
423   // success, and NULL on failure.  On success, the optional |size| argument
424   // is set to the size of the CodeView record.
425   const uint8_t* GetCVRecord(uint32_t* size);
426 
427   // The miscellaneous debug record, which is obsolete.  Current toolchains
428   // do not generate this type of debugging information (dbg), and this
429   // field is not expected to be present.  Returns a pointer to the debugging
430   // record on success, and NULL on failure.  On success, the optional |size|
431   // argument is set to the size of the debugging record.
432   const MDImageDebugMisc* GetMiscRecord(uint32_t* size);
433 
434   // Print a human-readable representation of the object to stdout.
435   void Print();
436 
437  private:
438   // These objects are managed by MinidumpModuleList.
439   friend class MinidumpModuleList;
440 
441   explicit MinidumpModule(Minidump* minidump);
442 
443   // This works like MinidumpStream::Read, but is driven by
444   // MinidumpModuleList.  No size checking is done, because
445   // MinidumpModuleList handles that directly.
446   bool Read();
447 
448   // Reads indirectly-referenced data, including the module name, CodeView
449   // record, and miscellaneous debugging record.  This is necessary to allow
450   // MinidumpModuleList to fully construct MinidumpModule objects without
451   // requiring seeks to read a contiguous set of MinidumpModule objects.
452   // All auxiliary data should be available when Read is called, in order to
453   // allow the CodeModule getters to be const methods.
454   bool ReadAuxiliaryData();
455 
456   // The largest number of bytes that will be read from a minidump for a
457   // CodeView record or miscellaneous debugging record, respectively.  The
458   // default for each is 1024.
459   static uint32_t max_cv_bytes_;
460   static uint32_t max_misc_bytes_;
461 
462   // True after a successful Read.  This is different from valid_, which is
463   // not set true until ReadAuxiliaryData also completes successfully.
464   // module_valid_ is only used by ReadAuxiliaryData and the functions it
465   // calls to determine whether the object is ready for auxiliary data to
466   // be read.
467   bool              module_valid_;
468 
469   // True if debug info was read from the module.  Certain modules
470   // may contain debug records in formats we don't support,
471   // so we can just set this to false to ignore them.
472   bool              has_debug_info_;
473 
474   MDRawModule       module_;
475 
476   // Cached module name.
477   const string*     name_;
478 
479   // Cached CodeView record - this is MDCVInfoPDB20 or (likely)
480   // MDCVInfoPDB70, or possibly something else entirely.  Stored as a uint8_t
481   // because the structure contains a variable-sized string and its exact
482   // size cannot be known until it is processed.
483   vector<uint8_t>* cv_record_;
484 
485   // If cv_record_ is present, cv_record_signature_ contains a copy of the
486   // CodeView record's first four bytes, for ease of determinining the
487   // type of structure that cv_record_ contains.
488   uint32_t cv_record_signature_;
489 
490   // Cached MDImageDebugMisc (usually not present), stored as uint8_t
491   // because the structure contains a variable-sized string and its exact
492   // size cannot be known until it is processed.
493   vector<uint8_t>* misc_record_;
494 };
495 
496 
497 // MinidumpModuleList contains all of the loaded code modules for a process
498 // in the form of MinidumpModules.  It maintains a map of these modules
499 // so that it may easily provide a code module corresponding to a specific
500 // address.
501 class MinidumpModuleList : public MinidumpStream,
502                            public CodeModules {
503  public:
504   virtual ~MinidumpModuleList();
505 
set_max_modules(uint32_t max_modules)506   static void set_max_modules(uint32_t max_modules) {
507     max_modules_ = max_modules;
508   }
max_modules()509   static uint32_t max_modules() { return max_modules_; }
510 
511   // CodeModules implementation.
module_count()512   virtual unsigned int module_count() const {
513     return valid_ ? module_count_ : 0;
514   }
515   virtual const MinidumpModule* GetModuleForAddress(uint64_t address) const;
516   virtual const MinidumpModule* GetMainModule() const;
517   virtual const MinidumpModule* GetModuleAtSequence(
518       unsigned int sequence) const;
519   virtual const MinidumpModule* GetModuleAtIndex(unsigned int index) const;
520   virtual const CodeModules* Copy() const;
521 
522   // Returns a vector of all modules which address ranges needed to be shrunk
523   // down due to address range conflicts with other modules.
524   virtual vector<linked_ptr<const CodeModule> > GetShrunkRangeModules() const;
525 
526   // Print a human-readable representation of the object to stdout.
527   void Print();
528 
529  protected:
530   explicit MinidumpModuleList(Minidump* minidump);
531 
532  private:
533   friend class Minidump;
534 
535   typedef vector<MinidumpModule> MinidumpModules;
536 
537   static const uint32_t kStreamType = MD_MODULE_LIST_STREAM;
538 
539   bool Read(uint32_t expected_size);
540 
541   bool StoreRange(const MinidumpModule& module,
542                   uint64_t base_address,
543                   uint32_t module_index,
544                   uint32_t module_count,
545                   bool is_android);
546 
547   // The largest number of modules that will be read from a minidump.  The
548   // default is 1024.
549   static uint32_t max_modules_;
550 
551   // Access to modules using addresses as the key.
552   RangeMap<uint64_t, unsigned int> *range_map_;
553 
554   MinidumpModules *modules_;
555   uint32_t module_count_;
556 
557   DISALLOW_COPY_AND_ASSIGN(MinidumpModuleList);
558 };
559 
560 
561 // MinidumpMemoryList corresponds to a minidump's MEMORY_LIST_STREAM stream,
562 // which references the snapshots of all of the memory regions contained
563 // within the minidump.  For a normal minidump, this includes stack memory
564 // (also referenced by each MinidumpThread, in fact, the MDMemoryDescriptors
565 // here and in MDRawThread both point to exactly the same data in a
566 // minidump file, conserving space), as well as a 256-byte snapshot of memory
567 // surrounding the instruction pointer in the case of an exception.  Other
568 // types of minidumps may contain significantly more memory regions.  Full-
569 // memory minidumps contain all of a process' mapped memory.
570 class MinidumpMemoryList : public MinidumpStream {
571  public:
572   virtual ~MinidumpMemoryList();
573 
set_max_regions(uint32_t max_regions)574   static void set_max_regions(uint32_t max_regions) {
575     max_regions_ = max_regions;
576   }
max_regions()577   static uint32_t max_regions() { return max_regions_; }
578 
region_count()579   unsigned int region_count() const { return valid_ ? region_count_ : 0; }
580 
581   // Sequential access to memory regions.
582   MinidumpMemoryRegion* GetMemoryRegionAtIndex(unsigned int index);
583 
584   // Random access to memory regions.  Returns the region encompassing
585   // the address identified by address.
586   virtual MinidumpMemoryRegion* GetMemoryRegionForAddress(uint64_t address);
587 
588   // Print a human-readable representation of the object to stdout.
589   void Print();
590 
591  private:
592   friend class Minidump;
593   friend class MockMinidumpMemoryList;
594 
595   typedef vector<MDMemoryDescriptor>   MemoryDescriptors;
596   typedef vector<MinidumpMemoryRegion> MemoryRegions;
597 
598   static const uint32_t kStreamType = MD_MEMORY_LIST_STREAM;
599 
600   explicit MinidumpMemoryList(Minidump* minidump);
601 
602   bool Read(uint32_t expected_size) override;
603 
604   // The largest number of memory regions that will be read from a minidump.
605   // The default is 256.
606   static uint32_t max_regions_;
607 
608   // Access to memory regions using addresses as the key.
609   RangeMap<uint64_t, unsigned int> *range_map_;
610 
611   // The list of descriptors.  This is maintained separately from the list
612   // of regions, because MemoryRegion doesn't own its MemoryDescriptor, it
613   // maintains a pointer to it.  descriptors_ provides the storage for this
614   // purpose.
615   MemoryDescriptors *descriptors_;
616 
617   // The list of regions.
618   MemoryRegions *regions_;
619   uint32_t region_count_;
620 
621   DISALLOW_COPY_AND_ASSIGN(MinidumpMemoryList);
622 };
623 
624 
625 // MinidumpException wraps MDRawExceptionStream, which contains information
626 // about the exception that caused the minidump to be generated, if the
627 // minidump was generated in an exception handler called as a result of an
628 // exception.  It also provides access to a MinidumpContext object, which
629 // contains the CPU context for the exception thread at the time the exception
630 // occurred.
631 class MinidumpException : public MinidumpStream {
632  public:
633   virtual ~MinidumpException();
634 
exception()635   const MDRawExceptionStream* exception() const {
636     return valid_ ? &exception_ : NULL;
637   }
638 
639   // The thread ID is used to determine if a thread is the exception thread,
640   // so a special getter is provided to retrieve this data from the
641   // MDRawExceptionStream structure.  Returns false if the thread ID cannot
642   // be determined.
643   bool GetThreadID(uint32_t *thread_id) const;
644 
645   MinidumpContext* GetContext();
646 
647   // Print a human-readable representation of the object to stdout.
648   void Print();
649 
650  private:
651   friend class Minidump;
652 
653   static const uint32_t kStreamType = MD_EXCEPTION_STREAM;
654 
655   explicit MinidumpException(Minidump* minidump);
656 
657   bool Read(uint32_t expected_size) override;
658 
659   MDRawExceptionStream exception_;
660   MinidumpContext*     context_;
661 
662   DISALLOW_COPY_AND_ASSIGN(MinidumpException);
663 };
664 
665 // MinidumpAssertion wraps MDRawAssertionInfo, which contains information
666 // about an assertion that caused the minidump to be generated.
667 class MinidumpAssertion : public MinidumpStream {
668  public:
669   virtual ~MinidumpAssertion();
670 
assertion()671   const MDRawAssertionInfo* assertion() const {
672     return valid_ ? &assertion_ : NULL;
673   }
674 
expression()675   string expression() const {
676     return valid_ ? expression_ : "";
677   }
678 
function()679   string function() const {
680     return valid_ ? function_ : "";
681   }
682 
file()683   string file() const {
684     return valid_ ? file_ : "";
685   }
686 
687   // Print a human-readable representation of the object to stdout.
688   void Print();
689 
690  private:
691   friend class Minidump;
692 
693   static const uint32_t kStreamType = MD_ASSERTION_INFO_STREAM;
694 
695   explicit MinidumpAssertion(Minidump* minidump);
696 
697   bool Read(uint32_t expected_size) override;
698 
699   MDRawAssertionInfo assertion_;
700   string expression_;
701   string function_;
702   string file_;
703 
704   DISALLOW_COPY_AND_ASSIGN(MinidumpAssertion);
705 };
706 
707 
708 // MinidumpSystemInfo wraps MDRawSystemInfo and provides information about
709 // the system on which the minidump was generated.  See also MinidumpMiscInfo.
710 class MinidumpSystemInfo : public MinidumpStream {
711  public:
712   virtual ~MinidumpSystemInfo();
713 
system_info()714   const MDRawSystemInfo* system_info() const {
715     return valid_ ? &system_info_ : NULL;
716   }
717 
718   // GetOS and GetCPU return textual representations of the operating system
719   // and CPU that produced the minidump.  Unlike most other Minidump* methods,
720   // they return string objects, not weak pointers.  Defined values for
721   // GetOS() are "mac", "windows", and "linux".  Defined values for GetCPU
722   // are "x86" and "ppc".  These methods return an empty string when their
723   // values are unknown.
724   string GetOS();
725   string GetCPU();
726 
727   // I don't know what CSD stands for, but this field is documented as
728   // returning a textual representation of the OS service pack.  On other
729   // platforms, this provides additional information about an OS version
730   // level beyond major.minor.micro.  Returns NULL if unknown.
731   const string* GetCSDVersion();
732 
733   // If a CPU vendor string can be determined, returns a pointer to it,
734   // otherwise, returns NULL.  CPU vendor strings can be determined from
735   // x86 CPUs with CPUID 0.
736   const string* GetCPUVendor();
737 
738   // Print a human-readable representation of the object to stdout.
739   void Print();
740 
741  protected:
742   explicit MinidumpSystemInfo(Minidump* minidump);
743   MDRawSystemInfo system_info_;
744 
745   // Textual representation of the OS service pack, for minidumps produced
746   // by MiniDumpWriteDump on Windows.
747   const string* csd_version_;
748 
749  private:
750   friend class Minidump;
751 
752   static const uint32_t kStreamType = MD_SYSTEM_INFO_STREAM;
753 
754   bool Read(uint32_t expected_size) override;
755 
756   // A string identifying the CPU vendor, if known.
757   const string* cpu_vendor_;
758 
759   DISALLOW_COPY_AND_ASSIGN(MinidumpSystemInfo);
760 };
761 
762 
763 // MinidumpUnloadedModule wraps MDRawUnloadedModule
764 class MinidumpUnloadedModule : public MinidumpObject,
765                                public CodeModule {
766  public:
767   ~MinidumpUnloadedModule() override;
768 
module()769   const MDRawUnloadedModule* module() const {
770     return valid_ ? &unloaded_module_ : NULL;
771   }
772 
773   // CodeModule implementation
base_address()774   uint64_t base_address() const override {
775     return valid_ ? unloaded_module_.base_of_image : 0;
776   }
size()777   uint64_t size() const override {
778     return valid_ ? unloaded_module_.size_of_image : 0;
779   }
780   string code_file() const override;
781   string code_identifier() const override;
782   string debug_file() const override;
783   string debug_identifier() const override;
784   string version() const override;
785   CodeModule* Copy() const override;
is_unloaded()786   bool is_unloaded() const override { return true; }
787   uint64_t shrink_down_delta() const override;
788   void SetShrinkDownDelta(uint64_t shrink_down_delta) override;
789 
790  protected:
791   explicit MinidumpUnloadedModule(Minidump* minidump);
792 
793  private:
794   // These objects are managed by MinidumpUnloadedModuleList
795   friend class MinidumpUnloadedModuleList;
796 
797   // This works like MinidumpStream::Read, but is driven by
798   // MinidumpUnloadedModuleList.
799   bool Read(uint32_t expected_size);
800 
801   // Reads the module name. This is done separately from Read to
802   // allow contiguous reading of code modules by MinidumpUnloadedModuleList.
803   bool ReadAuxiliaryData();
804 
805   // True after a successful Read. This is different from valid_, which
806   // is not set true until ReadAuxiliaryData also completes successfully.
807   // module_valid_ is only used by ReadAuxiliaryData and the functions it
808   // calls to determine whether the object is ready for auxiliary data to
809   // be read.
810   bool module_valid_;
811 
812   MDRawUnloadedModule unloaded_module_;
813 
814   // Cached module name
815   const string* name_;
816 };
817 
818 
819 // MinidumpUnloadedModuleList contains all the unloaded code modules for a
820 // process in the form of MinidumpUnloadedModules. It maintains a map of
821 // these modules so that it may easily provide a code module corresponding
822 // to a specific address. If multiple modules in the list have identical
823 // ranges, only the first module encountered is recorded in the range map.
824 class MinidumpUnloadedModuleList : public MinidumpStream,
825                                    public CodeModules {
826  public:
827   ~MinidumpUnloadedModuleList() override;
828 
set_max_modules(uint32_t max_modules)829   static void set_max_modules(uint32_t max_modules) {
830     max_modules_ = max_modules;
831   }
max_modules()832   static uint32_t max_modules() { return max_modules_; }
833 
834   // CodeModules implementation.
module_count()835   unsigned int module_count() const override {
836     return valid_ ? module_count_ : 0;
837   }
838   const MinidumpUnloadedModule*
839       GetModuleForAddress(uint64_t address) const override;
840   const MinidumpUnloadedModule* GetMainModule() const override;
841   const MinidumpUnloadedModule*
842       GetModuleAtSequence(unsigned int sequence) const override;
843   const MinidumpUnloadedModule*
844       GetModuleAtIndex(unsigned int index) const override;
845   const CodeModules* Copy() const override;
846   vector<linked_ptr<const CodeModule>> GetShrunkRangeModules() const override;
847 
848  protected:
849   explicit MinidumpUnloadedModuleList(Minidump* minidump_);
850 
851  private:
852   friend class Minidump;
853 
854   typedef vector<MinidumpUnloadedModule> MinidumpUnloadedModules;
855 
856   static const uint32_t kStreamType = MD_UNLOADED_MODULE_LIST_STREAM;
857 
858   bool Read(uint32_t expected_size_) override;
859 
860   // The largest number of modules that will be read from a minidump.  The
861   // default is 1024.
862   static uint32_t max_modules_;
863 
864   // Access to module indices using addresses as the key.
865   RangeMap<uint64_t, unsigned int> *range_map_;
866 
867   MinidumpUnloadedModules *unloaded_modules_;
868   uint32_t module_count_;
869 
870   DISALLOW_COPY_AND_ASSIGN(MinidumpUnloadedModuleList);
871 };
872 
873 
874 // MinidumpMiscInfo wraps MDRawMiscInfo and provides information about
875 // the process that generated the minidump, and optionally additional system
876 // information.  See also MinidumpSystemInfo.
877 class MinidumpMiscInfo : public MinidumpStream {
878  public:
misc_info()879   const MDRawMiscInfo* misc_info() const {
880     return valid_ ? &misc_info_ : NULL;
881   }
882 
883   // Print a human-readable representation of the object to stdout.
884   void Print();
885 
886  private:
887   friend class Minidump;
888   friend class TestMinidumpMiscInfo;
889 
890   static const uint32_t kStreamType = MD_MISC_INFO_STREAM;
891 
892   explicit MinidumpMiscInfo(Minidump* minidump_);
893 
894   bool Read(uint32_t expected_size_) override;
895 
896   MDRawMiscInfo misc_info_;
897 
898   // Populated by Read.  Contains the converted strings from the corresponding
899   // UTF-16 fields in misc_info_
900   string standard_name_;
901   string daylight_name_;
902   string build_string_;
903   string dbg_bld_str_;
904 
905   DISALLOW_COPY_AND_ASSIGN(MinidumpMiscInfo);
906 };
907 
908 
909 // MinidumpBreakpadInfo wraps MDRawBreakpadInfo, which is an optional stream in
910 // a minidump that provides additional information about the process state
911 // at the time the minidump was generated.
912 class MinidumpBreakpadInfo : public MinidumpStream {
913  public:
breakpad_info()914   const MDRawBreakpadInfo* breakpad_info() const {
915     return valid_ ? &breakpad_info_ : NULL;
916   }
917 
918   // These thread IDs are used to determine if threads deserve special
919   // treatment, so special getters are provided to retrieve this data from
920   // the MDRawBreakpadInfo structure.  The getters return false if the thread
921   // IDs cannot be determined.
922   bool GetDumpThreadID(uint32_t *thread_id) const;
923   bool GetRequestingThreadID(uint32_t *thread_id) const;
924 
925   // Print a human-readable representation of the object to stdout.
926   void Print();
927 
928  private:
929   friend class Minidump;
930 
931   static const uint32_t kStreamType = MD_BREAKPAD_INFO_STREAM;
932 
933   explicit MinidumpBreakpadInfo(Minidump* minidump_);
934 
935   bool Read(uint32_t expected_size_) override;
936 
937   MDRawBreakpadInfo breakpad_info_;
938 
939   DISALLOW_COPY_AND_ASSIGN(MinidumpBreakpadInfo);
940 };
941 
942 // MinidumpMemoryInfo wraps MDRawMemoryInfo, which provides information
943 // about mapped memory regions in a process, including their ranges
944 // and protection.
945 class MinidumpMemoryInfo : public MinidumpObject {
946  public:
info()947   const MDRawMemoryInfo* info() const { return valid_ ? &memory_info_ : NULL; }
948 
949   // The address of the base of the memory region.
GetBase()950   uint64_t GetBase() const { return valid_ ? memory_info_.base_address : 0; }
951 
952   // The size, in bytes, of the memory region.
GetSize()953   uint64_t GetSize() const { return valid_ ? memory_info_.region_size : 0; }
954 
955   // Return true if the memory protection allows execution.
956   bool IsExecutable() const;
957 
958   // Return true if the memory protection allows writing.
959   bool IsWritable() const;
960 
961   // Print a human-readable representation of the object to stdout.
962   void Print();
963 
964  private:
965   // These objects are managed by MinidumpMemoryInfoList.
966   friend class MinidumpMemoryInfoList;
967 
968   explicit MinidumpMemoryInfo(Minidump* minidump_);
969 
970   // This works like MinidumpStream::Read, but is driven by
971   // MinidumpMemoryInfoList.  No size checking is done, because
972   // MinidumpMemoryInfoList handles that directly.
973   bool Read();
974 
975   MDRawMemoryInfo memory_info_;
976 };
977 
978 // MinidumpMemoryInfoList contains a list of information about
979 // mapped memory regions for a process in the form of MDRawMemoryInfo.
980 // It maintains a map of these structures so that it may easily provide
981 // info corresponding to a specific address.
982 class MinidumpMemoryInfoList : public MinidumpStream {
983  public:
984   virtual ~MinidumpMemoryInfoList();
985 
info_count()986   unsigned int info_count() const { return valid_ ? info_count_ : 0; }
987 
988   const MinidumpMemoryInfo* GetMemoryInfoForAddress(uint64_t address) const;
989   const MinidumpMemoryInfo* GetMemoryInfoAtIndex(unsigned int index) const;
990 
991   // Print a human-readable representation of the object to stdout.
992   void Print();
993 
994  private:
995   friend class Minidump;
996 
997   typedef vector<MinidumpMemoryInfo> MinidumpMemoryInfos;
998 
999   static const uint32_t kStreamType = MD_MEMORY_INFO_LIST_STREAM;
1000 
1001   explicit MinidumpMemoryInfoList(Minidump* minidump_);
1002 
1003   bool Read(uint32_t expected_size) override;
1004 
1005   // Access to memory info using addresses as the key.
1006   RangeMap<uint64_t, unsigned int> *range_map_;
1007 
1008   MinidumpMemoryInfos* infos_;
1009   uint32_t info_count_;
1010 
1011   DISALLOW_COPY_AND_ASSIGN(MinidumpMemoryInfoList);
1012 };
1013 
1014 // MinidumpLinuxMaps wraps information about a single mapped memory region
1015 // from /proc/self/maps.
1016 class MinidumpLinuxMaps : public MinidumpObject {
1017  public:
1018   // The memory address of the base of the mapped region.
GetBase()1019   uint64_t GetBase() const { return valid_ ? region_.start : 0; }
1020   // The size of the mapped region.
GetSize()1021   uint64_t GetSize() const { return valid_ ? region_.end - region_.start : 0; }
1022 
1023   // The permissions of the mapped region.
IsReadable()1024   bool IsReadable() const {
1025     return valid_ ? region_.permissions & MappedMemoryRegion::READ : false;
1026   }
IsWriteable()1027   bool IsWriteable() const {
1028     return valid_ ? region_.permissions & MappedMemoryRegion::WRITE : false;
1029   }
IsExecutable()1030   bool IsExecutable() const {
1031     return valid_ ? region_.permissions & MappedMemoryRegion::EXECUTE : false;
1032   }
IsPrivate()1033   bool IsPrivate() const {
1034     return valid_ ? region_.permissions & MappedMemoryRegion::PRIVATE : false;
1035   }
1036 
1037   // The offset of the mapped region.
GetOffset()1038   uint64_t GetOffset() const { return valid_ ? region_.offset : 0; }
1039 
1040   // The major device number.
GetMajorDevice()1041   uint8_t GetMajorDevice() const { return valid_ ? region_.major_device : 0; }
1042   // The minor device number.
GetMinorDevice()1043   uint8_t GetMinorDevice() const { return valid_ ? region_.minor_device : 0; }
1044 
1045   // The inode of the mapped region.
GetInode()1046   uint64_t GetInode() const { return valid_ ? region_.inode : 0; }
1047 
1048   // The pathname of the mapped region.
GetPathname()1049   const string GetPathname() const { return valid_ ? region_.path : ""; }
1050 
1051   // Print the contents of this mapping.
1052   void Print() const;
1053 
1054  private:
1055   // These objects are managed by MinidumpLinuxMapsList.
1056   friend class MinidumpLinuxMapsList;
1057 
1058   // This caller owns the pointer.
1059   explicit MinidumpLinuxMaps(Minidump *minidump);
1060 
1061   // The memory region struct that this class wraps.
1062   MappedMemoryRegion region_;
1063 
1064   DISALLOW_COPY_AND_ASSIGN(MinidumpLinuxMaps);
1065 };
1066 
1067 // MinidumpLinuxMapsList corresponds to the Linux-exclusive MD_LINUX_MAPS
1068 // stream, which contains the contents of /prod/self/maps, which contains
1069 // the mapped memory regions and their access permissions.
1070 class MinidumpLinuxMapsList : public MinidumpStream {
1071  public:
1072   virtual ~MinidumpLinuxMapsList();
1073 
1074   // Get number of mappings.
get_maps_count()1075   unsigned int get_maps_count() const { return valid_ ? maps_count_ : 0; }
1076 
1077   // Get mapping at the given memory address. The caller owns the pointer.
1078   const MinidumpLinuxMaps *GetLinuxMapsForAddress(uint64_t address) const;
1079   // Get mapping at the given index. The caller owns the pointer.
1080   const MinidumpLinuxMaps *GetLinuxMapsAtIndex(unsigned int index) const;
1081 
1082   // Print the contents of /proc/self/maps to stdout.
1083   void Print() const;
1084 
1085  private:
1086   friend class Minidump;
1087 
1088   typedef vector<MinidumpLinuxMaps *> MinidumpLinuxMappings;
1089 
1090   static const uint32_t kStreamType = MD_LINUX_MAPS;
1091 
1092   // The caller owns the pointer.
1093   explicit MinidumpLinuxMapsList(Minidump *minidump);
1094 
1095   // Read and load the contents of the process mapping data.
1096   // The stream should have data in the form of /proc/self/maps.
1097   // This method returns whether the stream was read successfully.
1098   bool Read(uint32_t expected_size) override;
1099 
1100   // The list of individual mappings.
1101   MinidumpLinuxMappings *maps_;
1102   // The number of mappings.
1103   uint32_t maps_count_;
1104 
1105   DISALLOW_COPY_AND_ASSIGN(MinidumpLinuxMapsList);
1106 };
1107 
1108 // MinidumpCrashpadInfo wraps MDRawCrashpadInfo, which is an optional stream in
1109 // a minidump that provides additional information about the process state
1110 // at the time the minidump was generated.
1111 class MinidumpCrashpadInfo : public MinidumpStream {
1112  public:
crashpad_info()1113   const MDRawCrashpadInfo* crashpad_info() const {
1114     return valid_ ? &crashpad_info_ : NULL;
1115   }
1116 
1117   // Print a human-readable representation of the object to stdout.
1118   void Print();
1119 
1120  private:
1121   friend class Minidump;
1122 
1123   static const uint32_t kStreamType = MD_CRASHPAD_INFO_STREAM;
1124 
1125   explicit MinidumpCrashpadInfo(Minidump* minidump_);
1126 
1127   bool Read(uint32_t expected_size);
1128 
1129   MDRawCrashpadInfo crashpad_info_;
1130   std::vector<uint32_t> module_crashpad_info_links_;
1131   std::vector<MDRawModuleCrashpadInfo> module_crashpad_info_;
1132   std::vector<std::vector<std::string>> module_crashpad_info_list_annotations_;
1133   std::vector<std::map<std::string, std::string>>
1134       module_crashpad_info_simple_annotations_;
1135   std::map<std::string, std::string> simple_annotations_;
1136 };
1137 
1138 
1139 // Minidump is the user's interface to a minidump file.  It wraps MDRawHeader
1140 // and provides access to the minidump's top-level stream directory.
1141 class Minidump {
1142  public:
1143   // path is the pathname of a file containing the minidump.
1144   explicit Minidump(const string& path,
1145                     bool hexdump=false,
1146                     unsigned int hexdump_width=16);
1147   // input is an istream wrapping minidump data. Minidump holds a
1148   // weak pointer to input, and the caller must ensure that the stream
1149   // is valid as long as the Minidump object is.
1150   explicit Minidump(std::istream& input);
1151 
1152   virtual ~Minidump();
1153 
1154   // path may be empty if the minidump was not opened from a file
path()1155   virtual string path() const {
1156     return path_;
1157   }
set_max_streams(uint32_t max_streams)1158   static void set_max_streams(uint32_t max_streams) {
1159     max_streams_ = max_streams;
1160   }
max_streams()1161   static uint32_t max_streams() { return max_streams_; }
1162 
set_max_string_length(uint32_t max_string_length)1163   static void set_max_string_length(uint32_t max_string_length) {
1164     max_string_length_ = max_string_length;
1165   }
max_string_length()1166   static uint32_t max_string_length() { return max_string_length_; }
1167 
header()1168   virtual const MDRawHeader* header() const { return valid_ ? &header_ : NULL; }
1169 
1170   // Reads the CPU information from the system info stream and generates the
1171   // appropriate CPU flags.  The returned context_cpu_flags are the same as
1172   // if the CPU type bits were set in the context_flags of a context record.
1173   // On success, context_cpu_flags will have the flags that identify the CPU.
1174   // If a system info stream is missing, context_cpu_flags will be 0.
1175   // Returns true if the current position in the stream was not changed.
1176   // Returns false when the current location in the stream was changed and the
1177   // attempt to restore the original position failed.
1178   bool GetContextCPUFlagsFromSystemInfo(uint32_t* context_cpu_flags);
1179 
1180   // Reads the minidump file's header and top-level stream directory.
1181   // The minidump is expected to be positioned at the beginning of the
1182   // header.  Read() sets up the stream list and map, and validates the
1183   // Minidump object.
1184   virtual bool Read();
1185 
1186   // The next set of methods are stubs that call GetStream.  They exist to
1187   // force code generation of the templatized API within the module, and
1188   // to avoid exposing an ugly API (GetStream needs to accept a garbage
1189   // parameter).
1190   virtual MinidumpThreadList* GetThreadList();
1191   virtual MinidumpModuleList* GetModuleList();
1192   virtual MinidumpMemoryList* GetMemoryList();
1193   virtual MinidumpException* GetException();
1194   virtual MinidumpAssertion* GetAssertion();
1195   virtual MinidumpSystemInfo* GetSystemInfo();
1196   virtual MinidumpUnloadedModuleList* GetUnloadedModuleList();
1197   virtual MinidumpMiscInfo* GetMiscInfo();
1198   virtual MinidumpBreakpadInfo* GetBreakpadInfo();
1199   virtual MinidumpMemoryInfoList* GetMemoryInfoList();
1200   MinidumpCrashpadInfo* GetCrashpadInfo();
1201 
1202   // The next method also calls GetStream, but is exclusive for Linux dumps.
1203   virtual MinidumpLinuxMapsList *GetLinuxMapsList();
1204 
1205   // The next set of methods are provided for users who wish to access
1206   // data in minidump files directly, while leveraging the rest of
1207   // this class and related classes to handle the basic minidump
1208   // structure and known stream types.
1209 
GetDirectoryEntryCount()1210   unsigned int GetDirectoryEntryCount() const {
1211     return valid_ ? header_.stream_count : 0;
1212   }
1213   const MDRawDirectory* GetDirectoryEntryAtIndex(unsigned int index) const;
1214 
1215   // The next 2 methods are lower-level I/O routines.  They use fd_.
1216 
1217   // Reads count bytes from the minidump at the current position into
1218   // the storage area pointed to by bytes.  bytes must be of sufficient
1219   // size.  After the read, the file position is advanced by count.
1220   bool ReadBytes(void* bytes, size_t count);
1221 
1222   // Sets the position of the minidump file to offset.
1223   bool SeekSet(off_t offset);
1224 
1225   // Returns the current position of the minidump file.
1226   off_t Tell();
1227 
1228   // Medium-level I/O routines.
1229 
1230   // ReadString returns a string which is owned by the caller!  offset
1231   // specifies the offset that a length-encoded string is stored at in the
1232   // minidump file.
1233   string* ReadString(off_t offset);
1234 
1235   bool ReadUTF8String(off_t offset, string* string_utf8);
1236 
1237   bool ReadStringList(off_t offset, std::vector<std::string>* string_list);
1238 
1239   bool ReadSimpleStringDictionary(
1240       off_t offset,
1241       std::map<std::string, std::string>* simple_string_dictionary);
1242 
1243   // SeekToStreamType positions the file at the beginning of a stream
1244   // identified by stream_type, and informs the caller of the stream's
1245   // length by setting *stream_length.  Because stream_map maps each stream
1246   // type to only one stream in the file, this might mislead the user into
1247   // thinking that the stream that this seeks to is the only stream with
1248   // type stream_type.  That can't happen for streams that these classes
1249   // deal with directly, because they're only supposed to be present in the
1250   // file singly, and that's verified when stream_map_ is built.  Users who
1251   // are looking for other stream types should be aware of this
1252   // possibility, and consider using GetDirectoryEntryAtIndex (possibly
1253   // with GetDirectoryEntryCount) if expecting multiple streams of the same
1254   // type in a single minidump file.
1255   bool SeekToStreamType(uint32_t stream_type, uint32_t* stream_length);
1256 
swap()1257   bool swap() const { return valid_ ? swap_ : false; }
1258 
is_big_endian()1259   bool is_big_endian() const { return valid_ ? is_big_endian_ : false; }
1260 
1261   // Print a human-readable representation of the object to stdout.
1262   void Print();
1263 
1264   // Is the OS Android.
1265   bool IsAndroid();
1266 
1267   // Determines the platform where the minidump was produced. |platform| is
1268   // valid iff this method returns true.
1269   bool GetPlatform(MDOSPlatform* platform);
1270 
1271   // Get current hexdump display settings.
HexdumpMode()1272   unsigned int HexdumpMode() const { return hexdump_ ? hexdump_width_ : 0; }
1273 
1274  private:
1275   // MinidumpStreamInfo is used in the MinidumpStreamMap.  It lets
1276   // the Minidump object locate interesting streams quickly, and
1277   // provides a convenient place to stash MinidumpStream objects.
1278   struct MinidumpStreamInfo {
MinidumpStreamInfoMinidumpStreamInfo1279     MinidumpStreamInfo() : stream_index(0), stream(NULL) {}
~MinidumpStreamInfoMinidumpStreamInfo1280     ~MinidumpStreamInfo() { delete stream; }
1281 
1282     // Index into the MinidumpDirectoryEntries vector
1283     unsigned int    stream_index;
1284 
1285     // Pointer to the stream if cached, or NULL if not yet populated
1286     MinidumpStream* stream;
1287   };
1288 
1289   typedef vector<MDRawDirectory> MinidumpDirectoryEntries;
1290   typedef map<uint32_t, MinidumpStreamInfo> MinidumpStreamMap;
1291 
1292   template<typename T> T* GetStream(T** stream);
1293 
1294   // Opens the minidump file, or if already open, seeks to the beginning.
1295   bool Open();
1296 
1297   // The largest number of top-level streams that will be read from a minidump.
1298   // Note that streams are only read (and only consume memory) as needed,
1299   // when directed by the caller.  The default is 128.
1300   static uint32_t max_streams_;
1301 
1302   // The maximum length of a UTF-16 string that will be read from a minidump
1303   // in 16-bit words.  The default is 1024.  UTF-16 strings are converted
1304   // to UTF-8 when stored in memory, and each UTF-16 word will be represented
1305   // by as many as 3 bytes in UTF-8.
1306   static unsigned int max_string_length_;
1307 
1308   MDRawHeader               header_;
1309 
1310   // The list of streams.
1311   MinidumpDirectoryEntries* directory_;
1312 
1313   // Access to streams using the stream type as the key.
1314   MinidumpStreamMap*        stream_map_;
1315 
1316   // The pathname of the minidump file to process, set in the constructor.
1317   // This may be empty if the minidump was opened directly from a stream.
1318   const string              path_;
1319 
1320   // The stream for all file I/O.  Used by ReadBytes and SeekSet.
1321   // Set based on the path in Open, or directly in the constructor.
1322   std::istream*             stream_;
1323 
1324   // swap_ is true if the minidump file should be byte-swapped.  If the
1325   // minidump was produced by a CPU that is other-endian than the CPU
1326   // processing the minidump, this will be true.  If the two CPUs are
1327   // same-endian, this will be false.
1328   bool                      swap_;
1329 
1330   // true if the minidump was produced by a big-endian cpu.
1331   bool                      is_big_endian_;
1332 
1333   // Validity of the Minidump structure, false immediately after
1334   // construction or after a failed Read(); true following a successful
1335   // Read().
1336   bool                      valid_;
1337 
1338   // Knobs for controlling display of memory printing.
1339   bool                      hexdump_;
1340   unsigned int              hexdump_width_;
1341 
1342   DISALLOW_COPY_AND_ASSIGN(Minidump);
1343 };
1344 
1345 
1346 }  // namespace google_breakpad
1347 
1348 
1349 #endif  // GOOGLE_BREAKPAD_PROCESSOR_MINIDUMP_H__
1350