Chromium Code Reviews
chromiumcodereview-hr@appspot.gserviceaccount.com (chromiumcodereview-hr) | Please choose your nickname with Settings | Help | Chromium Project | Gerrit Changes | Sign out
(856)

Unified Diff: util/mac/mach_o_image_reader.h

Issue 666483002: Create snapshot/mac and move some files from snapshot and util to there (Closed) Base URL: https://chromium.googlesource.com/crashpad/crashpad/+/master
Patch Set: Move process_reader, process_types, and mach_o_image*_reader from util/mac to snapshot/mac Created 6 years, 2 months ago
Use n/p to move between diff chunks; N/P to move between comments. Draft comments are only viewable by you.
Jump to:
View side-by-side diff with in-line comments
Download patch
« no previous file with comments | « util/mac/checked_mach_address_range_test.cc ('k') | util/mac/mach_o_image_reader.cc » ('j') | no next file with comments »
Expand Comments ('e') | Collapse Comments ('c') | Show Comments Hide Comments ('s')
Index: util/mac/mach_o_image_reader.h
diff --git a/util/mac/mach_o_image_reader.h b/util/mac/mach_o_image_reader.h
deleted file mode 100644
index ad39611103b8a50ab26298df495136b7fdcaf0c9..0000000000000000000000000000000000000000
--- a/util/mac/mach_o_image_reader.h
+++ /dev/null
@@ -1,343 +0,0 @@
-// Copyright 2014 The Crashpad Authors. All rights reserved.
-//
-// Licensed under the Apache License, Version 2.0 (the "License");
-// you may not use this file except in compliance with the License.
-// You may obtain a copy of the License at
-//
-// http://www.apache.org/licenses/LICENSE-2.0
-//
-// Unless required by applicable law or agreed to in writing, software
-// distributed under the License is distributed on an "AS IS" BASIS,
-// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-// See the License for the specific language governing permissions and
-// limitations under the License.
-
-#ifndef CRASHPAD_UTIL_MAC_MACH_O_IMAGE_READER_H_
-#define CRASHPAD_UTIL_MAC_MACH_O_IMAGE_READER_H_
-
-#include <mach/mach.h>
-#include <stdint.h>
-
-#include <map>
-#include <string>
-
-#include "base/basictypes.h"
-#include "base/memory/scoped_ptr.h"
-#include "util/misc/initialization_state_dcheck.h"
-#include "util/misc/uuid.h"
-#include "util/stdlib/pointer_container.h"
-#include "util/mac/process_types.h"
-
-namespace crashpad {
-
-class MachOImageSegmentReader;
-class MachOImageSymbolTableReader;
-class ProcessReader;
-
-//! \brief A reader for Mach-O images mapped into another process.
-//!
-//! This class is capable of reading both 32-bit (`mach_header`/`MH_MAGIC`) and
-//! 64-bit (`mach_header_64`/`MH_MAGIC_64`) images based on the bitness of the
-//! remote process.
-class MachOImageReader {
- public:
- MachOImageReader();
- ~MachOImageReader();
-
- //! \brief Reads the Mach-O image file’s load commands from another process.
- //!
- //! This method must only be called once on an object. This method must be
- //! called successfully before any other method in this class may be called.
- //!
- //! \param[in] process_reader The reader for the remote process.
- //! \param[in] address The address, in the remote process’ address space,
- //! where the `mach_header` or `mach_header_64` at the beginning of the
- //! image to be read is located. This address can be determined by reading
- //! the remote process’ dyld information (see
- //! util/mac/process_types/dyld_images.proctype).
- //! \param[in] name The module’s name, a string to be used in logged messages.
- //! This string is for diagnostic purposes only, and may be empty.
- //!
- //! \return `true` if the image was read successfully, including all load
- //! commands. `false` otherwise, with an appropriate message logged.
- bool Initialize(ProcessReader* process_reader,
- mach_vm_address_t address,
- const std::string& name);
-
- //! \brief Returns the Mach-O file type.
- //!
- //! This value comes from the `filetype` field of the `mach_header` or
- //! `mach_header_64`. Common values include `MH_EXECUTE`, `MH_DYLIB`,
- //! `MH_DYLINKER`, and `MH_BUNDLE`.
- uint32_t FileType() const { return file_type_; }
-
- //! \brief Returns the Mach-O image’s load address.
- //!
- //! This is the value passed as \a address to Initialize().
- mach_vm_address_t Address() const { return address_; }
-
- //! \brief Returns the mapped size of the Mach-O image’s `__TEXT` segment.
- //!
- //! Note that this is returns only the size of the `__TEXT` segment, not of
- //! any other segment. This is because the interface only allows one load
- //! address and size to be reported, but Mach-O image files may consist of
- //! multiple discontiguous segments. By convention, the `__TEXT` segment is
- //! always mapped at the beginning of a Mach-O image file, and it is the most
- //! useful for the expected intended purpose of collecting data to obtain
- //! stack backtraces. The implementation insists during initialization that
- //! the `__TEXT` segment be mapped at the beginning of the file.
- //!
- //! In practice, discontiguous segments are only found for images that have
- //! loaded out of the dyld shared cache, but the `__TEXT` segment’s size is
- //! returned for modules that loaded with contiguous segments as well for
- //! consistency.
- mach_vm_size_t Size() const { return size_; }
-
- //! \brief Returns the Mach-O image’s “slide,” the difference between its
- //! actual load address and its preferred load address.
- //!
- //! “Slide” is computed by subtracting the `__TEXT` segment’s preferred load
- //! address from its actual load address. It will be reported as a positive
- //! offset when the actual load address is greater than the preferred load
- //! address. The preferred load address is taken to be the segment’s reported
- //! `vmaddr` value.
- mach_vm_size_t Slide() const { return slide_; }
-
- //! \brief Obtain segment information by segment name.
- //!
- //! \param[in] segment_name The name of the segment to search for, for
- //! example, `"__TEXT"`.
- //!
- //! \return A pointer to the segment information if it was found, or `nullptr`
- //! if it was not found. The caller does not take ownership; the lifetime
- //! of the returned object is scoped to the lifetime of this
- //! MachOImageReader object.
- const MachOImageSegmentReader* GetSegmentByName(
- const std::string& segment_name) const;
-
- //! \brief Obtain section information by segment and section name.
- //!
- //! \param[in] segment_name The name of the segment to search for, for
- //! example, `"__TEXT"`.
- //! \param[in] section_name The name of the section within the segment to
- //! search for, for example, `"__text"`.
- //! \param[out] address The actual address that the section was loaded at in
- //! memory, taking any “slide” into account if the section did not load at
- //! its preferred address as stored in the Mach-O image file. This
- //! parameter can be `nullptr`.
- //!
- //! \return A pointer to the section information if it was found, or `nullptr`
- //! if it was not found. The caller does not take ownership; the lifetime
- //! of the returned object is scoped to the lifetime of this
- //! MachOImageReader object.
- //!
- //! No parameter is provided for the section’s size, because it can be
- //! obtained from the returned process_types::section::size field.
- //!
- //! \note The process_types::section::addr field gives the section’s preferred
- //! load address as stored in the Mach-O image file, and is not adjusted
- //! for any “slide” that may have occurred when the image was loaded. Use
- //! \a address to obtain the section’s actual load address.
- const process_types::section* GetSectionByName(
- const std::string& segment_name,
- const std::string& section_name,
- mach_vm_address_t* address) const;
-
- //! \brief Obtain section information by section index.
- //!
- //! \param[in] index The index of the section to return, in the order that it
- //! appears in the segment load commands. This is a 1-based index,
- //! matching the section number values used for `nlist::n_sect`.
- //! \param[out] containing_segment The segment that contains the section.
- //! This parameter can be `nullptr`. The caller does not take ownership;
- //! the lifetime of the returned object is scoped to the lifetime of this
- //! MachOImageReader object.
- //! \param[out] address The actual address that the section was loaded at in
- //! memory, taking any “slide” into account if the section did not load at
- //! its preferred address as stored in the Mach-O image file. This
- //! parameter can be `nullptr`.
- //!
- //! \return A pointer to the section information. If \a index is out of range,
- //! logs a warning and returns `nullptr`. The caller does not take
- //! ownership; the lifetime of the returned object is scoped to the
- //! lifetime of this MachOImageReader object.
- //!
- //! No parameter is provided for the section’s size, because it can be
- //! obtained from the returned process_types::section::size field.
- //!
- //! \note The process_types::section::addr field gives the section’s preferred
- //! load address as stored in the Mach-O image file, and is not adjusted
- //! for any “slide” that may have occurred when the image was loaded. Use
- //! \a address to obtain the section’s actual load address.
- //! \note Unlike MachOImageSegmentReader::GetSectionAtIndex(), this method
- //! accepts out-of-range values for \a index, and returns `nullptr`
- //! instead of aborting execution upon encountering an out-of-range value.
- //! This is because a Mach-O image file’s symbol table refers to this
- //! per-module section index, and an out-of-range index in that case
- //! should be treated as a data error (where the data is beyond this
- //! code’s control) and handled non-fatally by reporting the error to the
- //! caller.
- const process_types::section* GetSectionAtIndex(
- size_t index,
- const MachOImageSegmentReader** containing_segment,
- mach_vm_address_t* address) const;
-
- //! \brief Looks up a symbol in the image’s symbol table.
- //!
- //! This method is capable of locating external defined symbols. Specifically,
- //! this method can look up symbols that have these charcteristics:
- //! - `N_STAB` (debugging) and `N_PEXT` (private external) must not be set.
- //! - `N_EXT` (external) must be set.
- //! - The type must be `N_ABS` (absolute) or `N_SECT` (defined in section).
- //!
- //! `N_INDR` (indirect), `N_UNDF` (undefined), and `N_PBUD` (prebound
- //! undefined) symbols cannot be located through this mechanism.
- //!
- //! \param[in] name The name of the symbol to look up, “mangled” or
- //! “decorated” appropriately. For example, use `"_main"` to look up the
- //! symbol for the C `main()` function, and use `"__Z4Funcv"` to look up
- //! the symbol for the C++ `Func()` function. Contrary to `dlsym()`, the
- //! leading underscore must not be stripped when using this interface.
- //! \param[out] value If the lookup was successful, this will be set to the
- //! value of the symbol, adjusted for any “slide” as needed. The value can
- //! be used as an address in the remote process’ address space where the
- //! pointee of the symbol exists in memory.
- //!
- //! \return `true` if the symbol lookup was successful and the symbol was
- //! found. `false` otherwise, including error conditions (for which a
- //! warning message will be logged), modules without symbol tables, and
- //! symbol names not found in the symbol table.
- //!
- //! \note Symbol values returned via this interface are adjusted for “slide”
- //! as appropriate, in contrast to the underlying implementation,
- //! MachOImageSymbolTableReader::LookUpExternalDefinedSymbol().
- //!
- //! \warning Symbols that are resolved by running symbol resolvers
- //! (`.symbol_resolver`) are not properly handled by this interface. The
- //! address of the symbol resolver is returned because that’s what shows
- //! up in the symbol table, rather than the effective address of the
- //! resolved symbol as used by dyld after running the resolver. The only
- //! way to detect this situation would be to read the `LC_DYLD_INFO` or
- //! `LC_DYLD_INFO_ONLY` load command if present and looking for the
- //! `EXPORT_SYMBOL_FLAGS_STUB_AND_RESOLVER` flag, but that would just be
- //! able to detect symbols with a resolver, it would not be able to
- //! resolve them from out-of-process, so it’s not currently done.
- bool LookUpExternalDefinedSymbol(const std::string& name,
- mach_vm_address_t* value) const;
-
- //! \brief Returns a Mach-O dylib image’s current version.
- //!
- //! This information comes from the `dylib_current_version` field of a dylib’s
- //! `LC_ID_DYLIB` load command. For dylibs without this load command, `0` will
- //! be returned.
- //!
- //! This method may only be called on Mach-O images for which FileType()
- //! returns `MH_DYLIB`.
- uint32_t DylibVersion() const;
-
- //! \brief Returns a Mach-O image’s source version.
- //!
- //! This information comes from a Mach-O image’s `LC_SOURCE_VERSION` load
- //! command. For Mach-O images without this load command, `0` will be
- //! returned.
- uint64_t SourceVersion() const { return source_version_; }
-
- //! \brief Returns a Mach-O image’s UUID.
- //!
- //! This information comes from a Mach-O image’s `LC_UUID` load command. For
- //! Mach-O images without this load command, a zeroed-out UUID value will be
- //! returned.
- //
- // UUID is a name in this scope (referring to this method), so the parameter’s
- // type needs to be qualified with |crashpad::|.
- void UUID(crashpad::UUID* uuid) const;
-
- //! \brief Returns the dynamic linker’s pathname.
- //!
- //! The dynamic linker is normally /usr/lib/dyld.
- //!
- //! For executable images (those with file type `MH_EXECUTE`), this is the
- //! name provided in the `LC_LOAD_DYLINKER` load command, if any. For dynamic
- //! linker images (those with file type `MH_DYLINKER`), this is the name
- //! provided in the `LC_ID_DYLINKER` load command. In other cases, this will
- //! be empty.
- std::string DylinkerName() const { return dylinker_name_; }
-
- private:
- // A generic helper routine for the other Read*Command() methods.
- template <typename T>
- bool ReadLoadCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info,
- uint32_t expected_load_command_id,
- T* load_command);
-
- // The Read*Command() methods are subroutines called by Initialize(). They are
- // responsible for reading a single load command. They may update the member
- // fields of their MachOImageReader object. If they can’t make sense of a load
- // command, they return false.
- bool ReadSegmentCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info);
- bool ReadSymTabCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info);
- bool ReadDySymTabCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info);
- bool ReadIdDylibCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info);
- bool ReadDylinkerCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info);
- bool ReadUUIDCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info);
- bool ReadSourceVersionCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info);
- bool ReadUnexpectedCommand(mach_vm_address_t load_command_address,
- const std::string& load_command_info);
-
- // Performs deferred initialization of the symbol table. Because a module’s
- // symbol table is often not needed, this is not handled in Initialize(), but
- // is done lazily, on-demand as needed.
- //
- // symbol_table_initialized_ will be transitioned to the appropriate state. If
- // initialization completes successfully, this will be the valid state.
- // Otherwise, it will be left in the invalid state and a warning message will
- // be logged.
- //
- // Note that if the object contains no symbol table, symbol_table_initialized_
- // will be set to the valid state, but symbol_table_ will be nullptr.
- void InitializeSymbolTable() const;
-
- PointerVector<MachOImageSegmentReader> segments_;
- std::map<std::string, size_t> segment_map_;
- std::string module_info_;
- std::string dylinker_name_;
- crashpad::UUID uuid_;
- mach_vm_address_t address_;
- mach_vm_size_t size_;
- mach_vm_size_t slide_;
- uint64_t source_version_;
- scoped_ptr<process_types::symtab_command> symtab_command_;
- scoped_ptr<process_types::dysymtab_command> dysymtab_command_;
-
- // symbol_table_ (and symbol_table_initialized_) are mutable in order to
- // maintain LookUpExternalDefinedSymbol() as a const interface while allowing
- // lazy initialization via InitializeSymbolTable(). This is logical
- // const-ness, not physical const-ness.
- mutable scoped_ptr<MachOImageSymbolTableReader> symbol_table_;
-
- scoped_ptr<process_types::dylib_command> id_dylib_command_;
- ProcessReader* process_reader_; // weak
- uint32_t file_type_;
- InitializationStateDcheck initialized_;
-
- // symbol_table_initialized_ protects symbol_table_: symbol_table_ can only
- // be used when symbol_table_initialized_ is valid, although
- // symbol_table_initialized_ being valid doesn’t imply that symbol_table_ is
- // set. symbol_table_initialized_ will be valid without symbol_table_ being
- // set in modules that have no symbol table.
- mutable InitializationState symbol_table_initialized_;
-
- DISALLOW_COPY_AND_ASSIGN(MachOImageReader);
-};
-
-} // namespace crashpad
-
-#endif // CRASHPAD_UTIL_MAC_MACH_O_IMAGE_READER_H_
« no previous file with comments | « util/mac/checked_mach_address_range_test.cc ('k') | util/mac/mach_o_image_reader.cc » ('j') | no next file with comments »

Powered by Google App Engine
This is Rietveld 408576698