- const load_command* startCmds = NULL;
- if ( mh->magic == MH_MAGIC_64 )
- startCmds = (load_command*)((char *)mh + sizeof(mach_header_64));
- else if ( mh->magic == MH_MAGIC )
- startCmds = (load_command*)((char *)mh + sizeof(mach_header));
- else
- return 0; // not a mach-o file, or wrong endianness
-
- const load_command* const cmdsEnd = (load_command*)((char*)startCmds + mh->sizeofcmds);
- const dylib_command* dylibCmd;
- const load_command* cmd = startCmds;
- const char* dylibName;
- #if __IPHONE_OS_VERSION_MIN_REQUIRED
- uint32_t foundationVers = 0;
- #else
- uint32_t libSystemVers = 0;
- #endif
- for(uint32_t i = 0; i < mh->ncmds; ++i) {
- const load_command* nextCmd = (load_command*)((char *)cmd + cmd->cmdsize);
- // <rdar://problem/14381579&16050962> sanity check size of command
- if ( (cmd->cmdsize < 8) || (nextCmd > cmdsEnd) || (nextCmd < startCmds)) {
- return 0;
- }
- switch ( cmd->cmd ) {
- case LC_LOAD_DYLIB:
- case LC_LOAD_WEAK_DYLIB:
- case LC_LOAD_UPWARD_DYLIB:
- dylibCmd = (dylib_command*)cmd;
- // sanity check dylib command layout
- if ( dylibCmd->dylib.name.offset > cmd->cmdsize )
- return 0;
- dylibName = (char*)dylibCmd + dylibCmd->dylib.name.offset;
- #if __IPHONE_OS_VERSION_MIN_REQUIRED
- if ( strcmp(dylibName, "/System/Library/Frameworks/Foundation.framework/Foundation") == 0 )
- foundationVers = dylibCmd->dylib.current_version;
- #else
- if ( strcmp(dylibName, "/usr/lib/libSystem.B.dylib") == 0 )
- libSystemVers = dylibCmd->dylib.current_version;
- #endif
- break;
- }
- cmd = nextCmd;
- }
-
- struct DylibToOSMapping {
- uint32_t dylibVersion;
- uint32_t osVersion;
- };
-
- #if __IPHONE_OS_VERSION_MIN_REQUIRED
- static const DylibToOSMapping foundationMapping[] = {
- { PACKED_VERSION(678,24,0), DYLD_IOS_VERSION_2_0 },
- { PACKED_VERSION(678,26,0), DYLD_IOS_VERSION_2_1 },
- { PACKED_VERSION(678,29,0), DYLD_IOS_VERSION_2_2 },
- { PACKED_VERSION(678,47,0), DYLD_IOS_VERSION_3_0 },
- { PACKED_VERSION(678,51,0), DYLD_IOS_VERSION_3_1 },
- { PACKED_VERSION(678,60,0), DYLD_IOS_VERSION_3_2 },
- { PACKED_VERSION(751,32,0), DYLD_IOS_VERSION_4_0 },
- { PACKED_VERSION(751,37,0), DYLD_IOS_VERSION_4_1 },
- { PACKED_VERSION(751,49,0), DYLD_IOS_VERSION_4_2 },
- { PACKED_VERSION(751,58,0), DYLD_IOS_VERSION_4_3 },
- { PACKED_VERSION(881,0,0), DYLD_IOS_VERSION_5_0 },
- { PACKED_VERSION(890,1,0), DYLD_IOS_VERSION_5_1 },
- { PACKED_VERSION(992,0,0), DYLD_IOS_VERSION_6_0 },
- { PACKED_VERSION(993,0,0), DYLD_IOS_VERSION_6_1 },
- { PACKED_VERSION(1038,14,0),DYLD_IOS_VERSION_7_0 },
- { PACKED_VERSION(0,0,0), DYLD_IOS_VERSION_7_0 }
- // We don't need to expand this table because all recent
- // binaries have LC_VERSION_MIN_ load command.
- };