tools/profiler/shared-libraries-macos.cc

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include <AvailabilityMacros.h>
   7 #include <mach-o/loader.h>
   8 #include <mach-o/dyld_images.h>
   9 #include <mach/task_info.h>
  10 #include <mach/task.h>
  11 #include <mach/mach_init.h>
  12 #include <mach/mach_traps.h>
  13 #include <string.h>
  14 #include <stdlib.h>
  15 #include <vector>
  16 #include <sstream>
  17
  18 #include "shared-libraries.h"
  19
  20 #ifndef MAC_OS_X_VERSION_10_6
  21 #define MAC_OS_X_VERSION_10_6 1060
  22 #endif
  23
  24 #if MAC_OS_X_VERSION_MAX_ALLOWED < MAC_OS_X_VERSION_10_6
  25 // borrowed from Breakpad
  26 // Fallback declarations for TASK_DYLD_INFO and friends, introduced in
  27 // <mach/task_info.h> in the Mac OS X 10.6 SDK.
  28 #define TASK_DYLD_INFO 17
  29 struct task_dyld_info {
  30     mach_vm_address_t all_image_info_addr;
  31     mach_vm_size_t all_image_info_size;
  32   };
  33 typedef struct task_dyld_info task_dyld_info_data_t;
  34 typedef struct task_dyld_info *task_dyld_info_t;
  35 #define TASK_DYLD_INFO_COUNT (sizeof(task_dyld_info_data_t) / sizeof(natural_t))
  36
  37 #endif
  38
  39 // Architecture specific abstraction.
  40 #ifdef __i386__
  41 typedef mach_header platform_mach_header;
  42 typedef segment_command mach_segment_command_type;
  43 #define MACHO_MAGIC_NUMBER MH_MAGIC
  44 #define CMD_SEGMENT LC_SEGMENT
  45 #define seg_size uint32_t
  46 #else
  47 typedef mach_header_64 platform_mach_header;
  48 typedef segment_command_64 mach_segment_command_type;
  49 #define MACHO_MAGIC_NUMBER MH_MAGIC_64
  50 #define CMD_SEGMENT LC_SEGMENT_64
  51 #define seg_size uint64_t
  52 #endif
  53
  54 static
  55 void addSharedLibrary(const platform_mach_header* header, char *name, SharedLibraryInfo &info) {
  56   const struct load_command *cmd =
  57     reinterpret_cast<const struct load_command *>(header + 1);
  58
  59   seg_size size = 0;
  60   unsigned long long start = reinterpret_cast<unsigned long long>(header);
  61   // Find the cmd segment in the macho image. It will contain the offset we care about.
  62   const uint8_t *uuid_bytes = nullptr;
  63   for (unsigned int i = 0;
  64        cmd && (i < header->ncmds) && (uuid_bytes == nullptr || size == 0);
  65        ++i) {
  66     if (cmd->cmd == CMD_SEGMENT) {
  67       const mach_segment_command_type *seg =
  68         reinterpret_cast<const mach_segment_command_type *>(cmd);
  69
  70       if (!strcmp(seg->segname, "__TEXT")) {
  71         size = seg->vmsize;
  72       }
  73     } else if (cmd->cmd == LC_UUID) {
  74       const uuid_command *ucmd = reinterpret_cast<const uuid_command *>(cmd);
  75       uuid_bytes = ucmd->uuid;
  76     }
  77
  78     cmd = reinterpret_cast<const struct load_command *>
  79       (reinterpret_cast<const char *>(cmd) + cmd->cmdsize);
  80   }
  81
  82   std::stringstream uuid;
  83   uuid << std::hex << std::uppercase;
  84   if (uuid_bytes != nullptr) {
  85     for (int i = 0; i < 16; ++i) {
  86       uuid << ((uuid_bytes[i] & 0xf0) >> 4);
  87       uuid << (uuid_bytes[i] & 0xf);
  88     }
  89     uuid << '0';
  90   }
  91
  92   info.AddSharedLibrary(SharedLibrary(start, start + size, 0, uuid.str(),
  93                                       name));
  94 }
  95
  96 // Use dyld to inspect the macho image information. We can build the SharedLibraryEntry structure
  97 // giving us roughtly the same info as /proc/PID/maps in Linux.
  98 SharedLibraryInfo SharedLibraryInfo::GetInfoForSelf()
  99 {
 100   SharedLibraryInfo sharedLibraryInfo;
 101
 102   task_dyld_info_data_t task_dyld_info;
 103   mach_msg_type_number_t count = TASK_DYLD_INFO_COUNT;
 104   if (task_info(mach_task_self (), TASK_DYLD_INFO, (task_info_t)&task_dyld_info,
 105                 &count) != KERN_SUCCESS) {
 106     return sharedLibraryInfo;
 107   }
 108
 109   struct dyld_all_image_infos* aii = (struct dyld_all_image_infos*)task_dyld_info.all_image_info_addr;
 110   size_t infoCount = aii->infoArrayCount;
 111
 112   // Iterate through all dyld images (loaded libraries) to get their names
 113   // and offests.
 114   for (size_t i = 0; i < infoCount; ++i) {
 115     const dyld_image_info *info = &aii->infoArray[i];
 116
 117     // If the magic number doesn't match then go no further
 118     // since we're not pointing to where we think we are.
 119     if (info->imageLoadAddress->magic != MACHO_MAGIC_NUMBER) {
 120       continue;
 121     }
 122
 123     const platform_mach_header* header =
 124       reinterpret_cast<const platform_mach_header*>(info->imageLoadAddress);
 125
 126     // Add the entry for this image.
 127     addSharedLibrary(header, (char*)info->imageFilePath, sharedLibraryInfo);
 128
 129   }
 130   return sharedLibraryInfo;
 131 }
 132