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diff --git a/vendor/gimli-0.26.2/fixtures/self/README.md b/vendor/gimli-0.26.2/fixtures/self/README.md new file mode 100644 index 000000000..91053d9b4 --- /dev/null +++ b/vendor/gimli-0.26.2/fixtures/self/README.md @@ -0,0 +1,147 @@ +# What are these files? + +These files are the DWARF data generated for (an early version of) this +library. Each file corresponds is a section from the built library's object +file. By splitting the sections out to their own files, we don't need to worry +about cross platform and cross object file format issues when running examples. + +# Updating and adding new sections + +## macOS + +Use `otool` to list the sections of a binary: + +``` +$ otool -l path/to/binary +``` + +You should see output similar to this: + +``` +Load command 0 + cmd LC_SEGMENT_64 + cmdsize 72 + segname __PAGEZERO + vmaddr 0x0000000000000000 + vmsize 0x0000000100000000 + fileoff 0 + filesize 0 + maxprot 0x00000000 + initprot 0x00000000 + nsects 0 + flags 0x0 +Load command 1 + cmd LC_SEGMENT_64 + cmdsize 712 + segname __TEXT + vmaddr 0x0000000100000000 + vmsize 0x00000000001b7000 + fileoff 0 + filesize 1798144 + maxprot 0x00000007 + initprot 0x00000005 + nsects 8 + flags 0x0 +Section + sectname __text + segname __TEXT + addr 0x0000000100000a50 + size 0x0000000000170716 + offset 2640 + align 2^4 (16) + reloff 0 + nreloc 0 + flags 0x80000400 + reserved1 0 + reserved2 0 +``` + +Etc. + +Find the `Section` entry of the section you'd like to isolate. For example, if +you're looking for `eh_frame`, find an entry like this: + +``` +Section + sectname __eh_frame + segname __TEXT + addr 0x0000000100192f38 + size 0x00000000000240c8 + offset 1650488 + align 2^3 (8) + reloff 0 + nreloc 0 + flags 0x00000000 + reserved1 0 + reserved2 0 +``` + +Then use `dd` to copy `size` bytes starting from `offset`: + +``` +$ dd bs=1 skip=1650488 count=$(printf "%d" 0x00000000000240c8) if=path/to/binary of=fixtures/self/eh_frame +``` + +Finally, use `otool` and `hexdump` to verify that the isolated section has the +same data as the section within the binary: + +``` +$ otool -s __TEXT __eh_frame path/to/binary | head +path/to/binary: +Contents of (__TEXT,__eh_frame) section +0000000100192f38 14 00 00 00 00 00 00 00 01 7a 52 00 01 78 10 01 +0000000100192f48 10 0c 07 08 90 01 00 00 24 00 00 00 1c 00 00 00 +0000000100192f58 f8 da e6 ff ff ff ff ff 66 00 00 00 00 00 00 00 +0000000100192f68 00 41 0e 10 86 02 43 0d 06 00 00 00 00 00 00 00 +0000000100192f78 1c 00 00 00 00 00 00 00 01 7a 50 4c 52 00 01 78 +0000000100192f88 10 07 9b 9d 40 02 00 10 10 0c 07 08 90 01 00 00 +0000000100192f98 2c 00 00 00 24 00 00 00 20 db e6 ff ff ff ff ff +0000000100192fa8 8d 00 00 00 00 00 00 00 08 37 e7 fd ff ff ff ff + +$ otool -s __TEXT __eh_frame path/to/binary | tail +00000001001b6f68 9a 0a 00 00 00 00 00 00 00 41 0e 10 86 02 43 0d +00000001001b6f78 06 50 83 07 8c 06 8d 05 8e 04 8f 03 00 00 00 00 +00000001001b6f88 24 00 00 00 7c 0e 00 00 30 a0 fb ff ff ff ff ff +00000001001b6f98 15 00 00 00 00 00 00 00 00 41 0e 10 86 02 43 0d +00000001001b6fa8 06 00 00 00 00 00 00 00 24 00 00 00 a4 0e 00 00 +00000001001b6fb8 28 a0 fb ff ff ff ff ff 1c 00 00 00 00 00 00 00 +00000001001b6fc8 00 41 0e 10 86 02 43 0d 06 00 00 00 00 00 00 00 +00000001001b6fd8 24 00 00 00 cc 0e 00 00 20 a0 fb ff ff ff ff ff +00000001001b6fe8 66 01 00 00 00 00 00 00 00 41 0e 10 86 02 43 0d +00000001001b6ff8 06 00 00 00 00 00 00 00 +``` + +This should be the same, ignoring the leading offsets: + +``` +$ hexdump fixtures/self/eh_frame | head +0000000 14 00 00 00 00 00 00 00 01 7a 52 00 01 78 10 01 +0000010 10 0c 07 08 90 01 00 00 24 00 00 00 1c 00 00 00 +0000020 f8 da e6 ff ff ff ff ff 66 00 00 00 00 00 00 00 +0000030 00 41 0e 10 86 02 43 0d 06 00 00 00 00 00 00 00 +0000040 1c 00 00 00 00 00 00 00 01 7a 50 4c 52 00 01 78 +0000050 10 07 9b 9d 40 02 00 10 10 0c 07 08 90 01 00 00 +0000060 2c 00 00 00 24 00 00 00 20 db e6 ff ff ff ff ff +0000070 8d 00 00 00 00 00 00 00 08 37 e7 fd ff ff ff ff +0000080 ff 41 0e 10 86 02 43 0d 06 00 00 00 00 00 00 00 +0000090 24 00 00 00 94 00 00 00 80 db e6 ff ff ff ff ff + +$ hexdump fixtures/self/eh_frame | tail +0024040 06 50 83 07 8c 06 8d 05 8e 04 8f 03 00 00 00 00 +0024050 24 00 00 00 7c 0e 00 00 30 a0 fb ff ff ff ff ff +0024060 15 00 00 00 00 00 00 00 00 41 0e 10 86 02 43 0d +0024070 06 00 00 00 00 00 00 00 24 00 00 00 a4 0e 00 00 +0024080 28 a0 fb ff ff ff ff ff 1c 00 00 00 00 00 00 00 +0024090 00 41 0e 10 86 02 43 0d 06 00 00 00 00 00 00 00 +00240a0 24 00 00 00 cc 0e 00 00 20 a0 fb ff ff ff ff ff +00240b0 66 01 00 00 00 00 00 00 00 41 0e 10 86 02 43 0d +00240c0 06 00 00 00 00 00 00 00 +``` + +## Linux + +Something like this: + +``` +objcopy --dump-section .eh_frame=fixtures/self/eh_frame path/to/binary +``` |