Breakpad Mac symbol dumper: Add new Mach-O reader class.

This patch adds files defining new classes in the google_breakpad::Mach_O
namespace for parsing fat binaries and Mach-O files. These are used in the
new dumper to handle STABS debugging information, DWARF call frame
information, and .eh_frame exception handling stack walking information.

These new classes are independent of endianness and word size, and
therefore can be used on binaries of all the relevant architectures: x86,
x86_64, ppc, and ARM.

The patch adds a complete set of unit tests for the new classes.
A=jimb R=mark (http://breakpad.appspot.com/93001/show, http://breakpad.appspot.com/115001/show)

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@610 4c0a9323-5329-0410-9bdc-e9ce6186880e

2 files changed, 399 insertions, 6 deletions

diff --git a/src/tools/mac/dump_syms/dump_syms.xcodeproj/project.pbxproj b/src/tools/mac/dump_syms/dump_syms.xcodeproj/project.pbxproj
index d6b6d7e0..0c345928 100644
--- a/src/tools/mac/dump_syms/dump_syms.xcodeproj/project.pbxproj
+++ b/src/tools/mac/dump_syms/dump_syms.xcodeproj/project.pbxproj
@@ -7,7 +7,15 @@
 	objects = {
 
 /* Begin PBXBuildFile section */
+		B88FAE0B11665B5700407530 /* test_assembler.cc in Sources */ = {isa = PBXBuildFile; fileRef = B88FAE0911665B5700407530 /* test_assembler.cc */; };
 		B89E0E601166556C00DD08C9 /* libcrypto.dylib in Frameworks */ = {isa = PBXBuildFile; fileRef = B89E0E5F1166556C00DD08C9 /* libcrypto.dylib */; };
+		B89E0E781166576C00DD08C9 /* macho_reader.cc in Sources */ = {isa = PBXBuildFile; fileRef = B89E0E6E1166571D00DD08C9 /* macho_reader.cc */; };
+		B89E0E7A1166576C00DD08C9 /* macho_dump.cc in Sources */ = {isa = PBXBuildFile; fileRef = B89E0E701166573700DD08C9 /* macho_dump.cc */; };
+		B89E0E9911665A7200DD08C9 /* macho_reader_unittest.cc in Sources */ = {isa = PBXBuildFile; fileRef = B89E0E6D1166571D00DD08C9 /* macho_reader_unittest.cc */; };
+		B89E0E9A11665A7200DD08C9 /* macho_reader.cc in Sources */ = {isa = PBXBuildFile; fileRef = B89E0E6E1166571D00DD08C9 /* macho_reader.cc */; };
+		B89E0EA111665AC300DD08C9 /* gtest_main.cc in Sources */ = {isa = PBXBuildFile; fileRef = B89E0E9F11665AC300DD08C9 /* gtest_main.cc */; };
+		B89E0EA211665AC300DD08C9 /* gtest-all.cc in Sources */ = {isa = PBXBuildFile; fileRef = B89E0EA011665AC300DD08C9 /* gtest-all.cc */; };
+		B89E0EA411665AEA00DD08C9 /* gmock-all.cc in Sources */ = {isa = PBXBuildFile; fileRef = B89E0EA311665AEA00DD08C9 /* gmock-all.cc */; };
 		B8C5B5161166534700D34F4E /* functioninfo.cc in Sources */ = {isa = PBXBuildFile; fileRef = F9C7ED420E8AD93000E953AD /* functioninfo.cc */; };
 		B8C5B5171166534700D34F4E /* dwarf2reader.cc in Sources */ = {isa = PBXBuildFile; fileRef = F95B422F0E0E22D100DBDE83 /* dwarf2reader.cc */; };
 		B8C5B5181166534700D34F4E /* bytereader.cc in Sources */ = {isa = PBXBuildFile; fileRef = F95B422C0E0E22D100DBDE83 /* bytereader.cc */; };
@@ -33,7 +41,18 @@
 		9BE650440B52F6D800611104 /* macho_id.h */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.c.h; name = macho_id.h; path = ../../../common/mac/macho_id.h; sourceTree = SOURCE_ROOT; };
 		9BE650450B52F6D800611104 /* macho_walker.cc */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.cpp.cpp; name = macho_walker.cc; path = ../../../common/mac/macho_walker.cc; sourceTree = SOURCE_ROOT; };
 		9BE650460B52F6D800611104 /* macho_walker.h */ = {isa = PBXFileReference; fileEncoding = 30; lastKnownFileType = sourcecode.c.h; name = macho_walker.h; path = ../../../common/mac/macho_walker.h; sourceTree = SOURCE_ROOT; };
+		B88FAE0911665B5700407530 /* test_assembler.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = test_assembler.cc; path = ../../../common/test_assembler.cc; sourceTree = SOURCE_ROOT; };
+		B88FAE0A11665B5700407530 /* test_assembler.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = test_assembler.h; path = ../../../common/test_assembler.h; sourceTree = SOURCE_ROOT; };
 		B89E0E5F1166556C00DD08C9 /* libcrypto.dylib */ = {isa = PBXFileReference; lastKnownFileType = "compiled.mach-o.dylib"; name = libcrypto.dylib; path = /usr/lib/libcrypto.dylib; sourceTree = "<absolute>"; };
+		B89E0E6D1166571D00DD08C9 /* macho_reader_unittest.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = macho_reader_unittest.cc; path = ../../../common/mac/macho_reader_unittest.cc; sourceTree = SOURCE_ROOT; };
+		B89E0E6E1166571D00DD08C9 /* macho_reader.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = macho_reader.cc; path = ../../../common/mac/macho_reader.cc; sourceTree = SOURCE_ROOT; };
+		B89E0E6F1166571D00DD08C9 /* macho_reader.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = macho_reader.h; path = ../../../common/mac/macho_reader.h; sourceTree = SOURCE_ROOT; };
+		B89E0E701166573700DD08C9 /* macho_dump.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; path = macho_dump.cc; sourceTree = "<group>"; };
+		B89E0E741166575200DD08C9 /* macho_dump */ = {isa = PBXFileReference; explicitFileType = "compiled.mach-o.executable"; includeInIndex = 0; path = macho_dump; sourceTree = BUILT_PRODUCTS_DIR; };
+		B89E0E9511665A6400DD08C9 /* macho_reader_unittest */ = {isa = PBXFileReference; explicitFileType = "compiled.mach-o.executable"; includeInIndex = 0; path = macho_reader_unittest; sourceTree = BUILT_PRODUCTS_DIR; };
+		B89E0E9F11665AC300DD08C9 /* gtest_main.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = gtest_main.cc; path = ../../../testing/gtest/src/gtest_main.cc; sourceTree = SOURCE_ROOT; };
+		B89E0EA011665AC300DD08C9 /* gtest-all.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = "gtest-all.cc"; path = "../../../testing/gtest/src/gtest-all.cc"; sourceTree = SOURCE_ROOT; };
+		B89E0EA311665AEA00DD08C9 /* gmock-all.cc */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = "gmock-all.cc"; path = "../../../testing/src/gmock-all.cc"; sourceTree = SOURCE_ROOT; };
 		B8C5B5111166531A00D34F4E /* dump_syms */ = {isa = PBXFileReference; explicitFileType = "compiled.mach-o.executable"; includeInIndex = 0; path = dump_syms; sourceTree = BUILT_PRODUCTS_DIR; };
 		B8E8CA0C1156C854009E61B2 /* byteswap.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = byteswap.h; path = ../../../common/mac/byteswap.h; sourceTree = SOURCE_ROOT; };
 		F95B422B0E0E22D100DBDE83 /* bytereader-inl.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = "bytereader-inl.h"; path = "../../../common/dwarf/bytereader-inl.h"; sourceTree = SOURCE_ROOT; };
@@ -48,6 +67,20 @@
 /* End PBXFileReference section */
 
 /* Begin PBXFrameworksBuildPhase section */
+		B89E0E721166575200DD08C9 /* Frameworks */ = {
+			isa = PBXFrameworksBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+		B89E0E9311665A6400DD08C9 /* Frameworks */ = {
+			isa = PBXFrameworksBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 		B8C5B50F1166531A00D34F4E /* Frameworks */ = {
 			isa = PBXFrameworksBuildPhase;
 			buildActionMask = 2147483647;
@@ -63,19 +96,16 @@
 		08FB7794FE84155DC02AAC07 /* dump_syms */ = {
 			isa = PBXGroup;
 			children = (
+				B89E0E9D11665A9500DD08C9 /* TESTING */,
 				F9F5344B0E7C8FFC0012363F /* DWARF */,
+				B89E0E6C1166569700DD08C9 /* MACHO */,
 				B8E8CA0C1156C854009E61B2 /* byteswap.h */,
-				557800890BE1F3AB00EC23E0 /* macho_utilities.cc */,
-				5578008A0BE1F3AB00EC23E0 /* macho_utilities.h */,
 				9BE650410B52F6D800611104 /* file_id.cc */,
 				9BE650420B52F6D800611104 /* file_id.h */,
-				9BE650430B52F6D800611104 /* macho_id.cc */,
-				9BE650440B52F6D800611104 /* macho_id.h */,
-				9BE650450B52F6D800611104 /* macho_walker.cc */,
-				9BE650460B52F6D800611104 /* macho_walker.h */,
 				9BDF186D0B1BB43700F8391B /* dump_syms.h */,
 				08FB7796FE84155DC02AAC07 /* dump_syms.mm */,
 				9BDF186E0B1BB43700F8391B /* dump_syms_tool.mm */,
+				B89E0E701166573700DD08C9 /* macho_dump.cc */,
 				08FB779DFE84155DC02AAC07 /* External Frameworks and Libraries */,
 				1AB674ADFE9D54B511CA2CBB /* Products */,
 			);
@@ -95,10 +125,40 @@
 			isa = PBXGroup;
 			children = (
 				B8C5B5111166531A00D34F4E /* dump_syms */,
+				B89E0E741166575200DD08C9 /* macho_dump */,
+				B89E0E9511665A6400DD08C9 /* macho_reader_unittest */,
 			);
 			name = Products;
 			sourceTree = "<group>";
 		};
+		B89E0E6C1166569700DD08C9 /* MACHO */ = {
+			isa = PBXGroup;
+			children = (
+				B89E0E6D1166571D00DD08C9 /* macho_reader_unittest.cc */,
+				B89E0E6E1166571D00DD08C9 /* macho_reader.cc */,
+				B89E0E6F1166571D00DD08C9 /* macho_reader.h */,
+				557800890BE1F3AB00EC23E0 /* macho_utilities.cc */,
+				5578008A0BE1F3AB00EC23E0 /* macho_utilities.h */,
+				9BE650430B52F6D800611104 /* macho_id.cc */,
+				9BE650440B52F6D800611104 /* macho_id.h */,
+				9BE650450B52F6D800611104 /* macho_walker.cc */,
+				9BE650460B52F6D800611104 /* macho_walker.h */,
+			);
+			name = MACHO;
+			sourceTree = "<group>";
+		};
+		B89E0E9D11665A9500DD08C9 /* TESTING */ = {
+			isa = PBXGroup;
+			children = (
+				B88FAE0911665B5700407530 /* test_assembler.cc */,
+				B88FAE0A11665B5700407530 /* test_assembler.h */,
+				B89E0EA311665AEA00DD08C9 /* gmock-all.cc */,
+				B89E0E9F11665AC300DD08C9 /* gtest_main.cc */,
+				B89E0EA011665AC300DD08C9 /* gtest-all.cc */,
+			);
+			name = TESTING;
+			sourceTree = "<group>";
+		};
 		F9F5344B0E7C8FFC0012363F /* DWARF */ = {
 			isa = PBXGroup;
 			children = (
@@ -118,6 +178,38 @@
 /* End PBXGroup section */
 
 /* Begin PBXNativeTarget section */
+		B89E0E731166575200DD08C9 /* macho_dump */ = {
+			isa = PBXNativeTarget;
+			buildConfigurationList = B89E0E7F116657A100DD08C9 /* Build configuration list for PBXNativeTarget "macho_dump" */;
+			buildPhases = (
+				B89E0E711166575200DD08C9 /* Sources */,
+				B89E0E721166575200DD08C9 /* Frameworks */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+			);
+			name = macho_dump;
+			productName = macho_dump;
+			productReference = B89E0E741166575200DD08C9 /* macho_dump */;
+			productType = "com.apple.product-type.tool";
+		};
+		B89E0E9411665A6400DD08C9 /* macho_reader_unittest */ = {
+			isa = PBXNativeTarget;
+			buildConfigurationList = B89E0E9E11665A9600DD08C9 /* Build configuration list for PBXNativeTarget "macho_reader_unittest" */;
+			buildPhases = (
+				B89E0E9211665A6400DD08C9 /* Sources */,
+				B89E0E9311665A6400DD08C9 /* Frameworks */,
+			);
+			buildRules = (
+			);
+			dependencies = (
+			);
+			name = macho_reader_unittest;
+			productName = macho_reader_unittest;
+			productReference = B89E0E9511665A6400DD08C9 /* macho_reader_unittest */;
+			productType = "com.apple.product-type.tool";
+		};
 		B8C5B5101166531A00D34F4E /* dump_syms */ = {
 			isa = PBXNativeTarget;
 			buildConfigurationList = B8C5B5151166533900D34F4E /* Build configuration list for PBXNativeTarget "dump_syms" */;
@@ -139,6 +231,9 @@
 /* Begin PBXProject section */
 		08FB7793FE84155DC02AAC07 /* Project object */ = {
 			isa = PBXProject;
+			attributes = {
+				BuildIndependentTargetsInParallel = NO;
+			};
 			buildConfigurationList = 1DEB927808733DD40010E9CD /* Build configuration list for PBXProject "dump_syms" */;
 			compatibilityVersion = "Xcode 2.4";
 			hasScannedForEncodings = 1;
@@ -147,11 +242,35 @@
 			projectRoot = "";
 			targets = (
 				B8C5B5101166531A00D34F4E /* dump_syms */,
+				B89E0E731166575200DD08C9 /* macho_dump */,
+				B89E0E9411665A6400DD08C9 /* macho_reader_unittest */,
 			);
 		};
 /* End PBXProject section */
 
 /* Begin PBXSourcesBuildPhase section */
+		B89E0E711166575200DD08C9 /* Sources */ = {
+			isa = PBXSourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				B89E0E781166576C00DD08C9 /* macho_reader.cc in Sources */,
+				B89E0E7A1166576C00DD08C9 /* macho_dump.cc in Sources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
+		B89E0E9211665A6400DD08C9 /* Sources */ = {
+			isa = PBXSourcesBuildPhase;
+			buildActionMask = 2147483647;
+			files = (
+				B89E0E9911665A7200DD08C9 /* macho_reader_unittest.cc in Sources */,
+				B89E0E9A11665A7200DD08C9 /* macho_reader.cc in Sources */,
+				B89E0EA111665AC300DD08C9 /* gtest_main.cc in Sources */,
+				B89E0EA211665AC300DD08C9 /* gtest-all.cc in Sources */,
+				B89E0EA411665AEA00DD08C9 /* gmock-all.cc in Sources */,
+				B88FAE0B11665B5700407530 /* test_assembler.cc in Sources */,
+			);
+			runOnlyForDeploymentPostprocessing = 0;
+		};
 		B8C5B50E1166531A00D34F4E /* Sources */ = {
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
@@ -192,6 +311,66 @@
 			};
 			name = Release;
 		};
+		B89E0E761166575300DD08C9 /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				COPY_PHASE_STRIP = NO;
+				GCC_DYNAMIC_NO_PIC = NO;
+				GCC_ENABLE_FIX_AND_CONTINUE = YES;
+				GCC_MODEL_TUNING = G5;
+				GCC_OPTIMIZATION_LEVEL = 0;
+				INSTALL_PATH = /usr/local/bin;
+				PREBINDING = NO;
+				PRODUCT_NAME = macho_dump;
+			};
+			name = Debug;
+		};
+		B89E0E771166575300DD08C9 /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				COPY_PHASE_STRIP = YES;
+				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
+				GCC_ENABLE_FIX_AND_CONTINUE = NO;
+				GCC_MODEL_TUNING = G5;
+				INSTALL_PATH = /usr/local/bin;
+				PREBINDING = NO;
+				PRODUCT_NAME = macho_dump;
+				ZERO_LINK = NO;
+			};
+			name = Release;
+		};
+		B89E0E9711665A6400DD08C9 /* Debug */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				COPY_PHASE_STRIP = NO;
+				GCC_DYNAMIC_NO_PIC = NO;
+				GCC_ENABLE_FIX_AND_CONTINUE = YES;
+				GCC_MODEL_TUNING = G5;
+				GCC_OPTIMIZATION_LEVEL = 0;
+				INSTALL_PATH = /usr/local/bin;
+				PREBINDING = NO;
+				PRODUCT_NAME = macho_reader_unittest;
+			};
+			name = Debug;
+		};
+		B89E0E9811665A6400DD08C9 /* Release */ = {
+			isa = XCBuildConfiguration;
+			buildSettings = {
+				ALWAYS_SEARCH_USER_PATHS = NO;
+				COPY_PHASE_STRIP = YES;
+				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
+				GCC_ENABLE_FIX_AND_CONTINUE = NO;
+				GCC_MODEL_TUNING = G5;
+				INSTALL_PATH = /usr/local/bin;
+				PREBINDING = NO;
+				PRODUCT_NAME = macho_reader_unittest;
+				ZERO_LINK = NO;
+			};
+			name = Release;
+		};
 		B8C5B5131166531B00D34F4E /* Debug */ = {
 			isa = XCBuildConfiguration;
 			buildSettings = {
@@ -235,6 +414,24 @@
 			defaultConfigurationIsVisible = 0;
 			defaultConfigurationName = Release;
 		};
+		B89E0E7F116657A100DD08C9 /* Build configuration list for PBXNativeTarget "macho_dump" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				B89E0E761166575300DD08C9 /* Debug */,
+				B89E0E771166575300DD08C9 /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
+		B89E0E9E11665A9600DD08C9 /* Build configuration list for PBXNativeTarget "macho_reader_unittest" */ = {
+			isa = XCConfigurationList;
+			buildConfigurations = (
+				B89E0E9711665A6400DD08C9 /* Debug */,
+				B89E0E9811665A6400DD08C9 /* Release */,
+			);
+			defaultConfigurationIsVisible = 0;
+			defaultConfigurationName = Release;
+		};
 		B8C5B5151166533900D34F4E /* Build configuration list for PBXNativeTarget "dump_syms" */ = {
 			isa = XCConfigurationList;
 			buildConfigurations = (
diff --git a/src/tools/mac/dump_syms/macho_dump.cc b/src/tools/mac/dump_syms/macho_dump.cc
new file mode 100644
index 00000000..fcef37c5
--- /dev/null
+++ b/src/tools/mac/dump_syms/macho_dump.cc
@@ -0,0 +1,196 @@
+// Copyright (c) 2010, Google Inc.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+// Original author: Jim Blandy <jimb@mozilla.com> <jimb@red-bean.com>
+
+// macho_dump.cc: Dump the contents of a Mach-O file. This is mostly
+// a test program for the Mach_O::FatReader and Mach_O::Reader classes.
+
+#include <errno.h>
+#include <fcntl.h>
+#include <libgen.h>
+#include <mach-o/arch.h>
+#include <sys/mman.h>
+#include <stdint.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include <sstream>
+#include <string>
+#include <vector>
+
+#include "common/byte_cursor.h"
+#include "common/mac/macho_reader.h"
+
+using google_breakpad::ByteBuffer;
+using std::ostringstream;
+using std::string;
+using std::vector;
+
+namespace {
+namespace mach_o = google_breakpad::mach_o;
+
+string program_name;
+
+int check_syscall(int result, const char *operation, const char *filename) {
+  if (result < 0) {
+    fprintf(stderr, "%s: %s '%s': %s\n",
+            program_name.c_str(), operation,
+            filename, strerror(errno));
+    exit(1);
+  }
+  return result;
+}
+
+class DumpSection: public mach_o::Reader::SectionHandler {
+ public:
+  DumpSection() : index_(0) { }
+  bool HandleSection(const mach_o::Section &section) {
+    printf("        section %d '%s' in segment '%s'\n"
+           "          address: 0x%llx\n"
+           "          alignment: 1 << %d B\n"
+           "          flags: %d\n"
+           "          size: %ld\n",
+           index_++, section.section_name.c_str(), section.segment_name.c_str(),
+           section.address, section.align,
+           mach_o::SectionFlags(section.flags),
+           section.contents.Size());
+    return true;
+  }
+         
+ private:
+  int index_;
+};
+
+class DumpCommand: public mach_o::Reader::LoadCommandHandler {
+ public:
+  DumpCommand(mach_o::Reader *reader) : reader_(reader), index_(0) { }
+  bool UnknownCommand(mach_o::LoadCommandType type,
+                      const ByteBuffer &contents) {
+    printf("      load command %d: %d", index_++, type);
+    return true;
+  }
+  bool SegmentCommand(const mach_o::Segment &segment) {
+    printf("      load command %d: %s-bit segment '%s'\n"
+           "        address: 0x%llx\n"
+           "        memory size: 0x%llx\n"
+           "        maximum protection: 0x%x\n"
+           "        initial protection: 0x%x\n"
+           "        flags: %d\n"
+           "        section_list size: %ld B\n",
+           index_++, (segment.bits_64 ? "64" : "32"), segment.name.c_str(),
+           segment.vmaddr, segment.vmsize, segment.maxprot,
+           segment.initprot, mach_o::SegmentFlags(segment.flags),
+           segment.section_list.Size());
+           
+    DumpSection dump_section;
+    return reader_->WalkSegmentSections(segment, &dump_section);
+  }
+ private:
+  mach_o::Reader *reader_;
+  int index_;
+};
+
+void DumpFile(const char *filename) {
+  int fd = check_syscall(open(filename, O_RDONLY), "opening", filename);
+  struct stat attributes;
+  check_syscall(fstat(fd, &attributes),
+                "getting file attributes for", filename);
+  void *mapping = mmap(NULL, attributes.st_size, PROT_READ,
+                       MAP_PRIVATE, fd, 0);
+  close(fd);
+  check_syscall(mapping == (void *)-1 ? -1 : 0,
+                "mapping contents of", filename);
+
+  mach_o::FatReader::Reporter fat_reporter(filename);
+  mach_o::FatReader fat_reader(&fat_reporter);
+  if (!fat_reader.Read(reinterpret_cast<uint8_t *>(mapping),
+                       attributes.st_size)) {
+    exit(1);
+  }
+  printf("filename: %s\n", filename);
+  size_t object_files_size;
+  struct fat_arch *object_files = fat_reader.object_files(&object_files_size);
+  printf("  object file count: %ld\n", object_files_size);
+  for (size_t i = 0; i < object_files_size; i++) {
+    const struct fat_arch &file = object_files[i];
+    const NXArchInfo *fat_arch_info
+      = NXGetArchInfoFromCpuType(file.cputype, file.cpusubtype);
+    printf("\n  object file %ld:\n"
+           "    fat header:\n:"
+           "      CPU type: %s (%s)\n"
+           "      size: %d B\n"
+           "      alignment: 1<<%d B\n",
+           i, fat_arch_info->name, fat_arch_info->description,
+           file.size, file.align);
+
+    ostringstream name;
+    name << filename;
+    if (object_files_size > 1)
+      name << ", object file #" << i;
+    ByteBuffer file_contents(reinterpret_cast<uint8_t *>(mapping)
+                             + file.offset, file.size);
+    mach_o::Reader::Reporter reporter(name.str());
+    mach_o::Reader reader(&reporter);
+    if (!reader.Read(file_contents, file.cputype, file.cpusubtype)) {
+      exit(1);
+    }
+
+    const NXArchInfo *macho_arch_info =
+      NXGetArchInfoFromCpuType(reader.cpu_type(),
+                               reader.cpu_subtype());
+    printf("    Mach-O header:\n"
+           "      word size: %s\n" 
+           "      CPU type: %s (%s)\n"
+           "      File type: %d\n"
+           "      flags: %x\n",
+           (reader.bits_64() ? "64 bits" : "32 bits"),
+           macho_arch_info->name, macho_arch_info->description,
+           reader.file_type(), reader.flags());
+
+    DumpCommand dump_command(&reader);
+    reader.WalkLoadCommands(&dump_command);
+  }
+  munmap(mapping, attributes.st_size);
+}
+
+}  // namespace
+
+int main(int argc, char **argv) {
+  program_name = basename(argv[0]);
+  if (argc == 1) {
+    fprintf(stderr, "Usage: %s FILE ...\n"
+            "Dump the contents of the Mach-O or fat binary files "
+            "'FILE ...'.\n", program_name.c_str());
+  }
+  for (int i = 1; i < argc; i++) {
+    DumpFile(argv[i]);
+  }
+}