Kode debug seperti berburu. Perburuan serangga.
- Amit Kalantri
Apa itu GDB
GNU Debugger adalah debugger portabel untuk proyek GNU yang berjalan pada banyak sistem mirip UNIX dan dapat men-debug banyak bahasa pemrograman, termasuk C, C ++, Free Pascal, FreeBASIC, Ada, Fortran, dan Rust. GDB adalah perangkat lunak gratis yang dirilis di bawah lisensi GPL.
Sumber: GNU Debugger - Wikipedia
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| Caesar::shift | Caesar |
| Caesar::ChangeShift | Caesar |
| Caesar::Crypt | Caesar |
(TUI)
TUI, GDB, , , . TUI GDB tui enable
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breakpoint
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b Method if variable == value
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(gdb) b Crypt if Caesar::shift == 1 Note: breakpoint 2 also set at pc 0x4026e3. Breakpoint 4 at 0x4026e3: file Caesar.h, line 55.
Crypt()
, Caesar
shift
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(gdb) display Caesar::shift 1: Caesar::shift = <error: Cannot reference non-static field "shift"> (gdb) n Breakpoint 2, Caesar::Crypt (this=0x7fffffffdc30, text="Crypt this text! Btw, xyz") at Caesar.h:55 1: Caesar::shift = 1 (gdb) n 1: Caesar::shift = 1 (gdb)
:
(gdb) display *stringArrayForOutput@lengthOfArray 1: *stringArrayForOutput@lengthOfArray = {"Etarv vjku vgzv! Dvy, zab", "Fubsw wklv whaw! Ewz, abc", "Gvctx xlmw xibx! Fxa, bcd"} (gdb)
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explore
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explore
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(gdb) explore Caesar::shift 'Caesar::shift' is a scalar value of type 'int'. Caesar::shift = 6 (gdb) explore Caesar 'Caesar' is a struct/class with the following fields: letters = <Enter 0 to explore this field of type 'std::string'> shift = <Enter 1 to explore this field of type 'int'>
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(gdb) target record-full (gdb) p Caesar::shift $1 = 6 (gdb) n (gdb) p Caesar::shift $2 = 7 (gdb) reverse-next No more reverse-execution history. (gdb) p Caesar::shift $3 = 6
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info local
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(gdb) info local mainObj = {letters = "abcdefghijklmnopqrstuvwxyz", shift = 1} textForC = "Crypt this text! Btw, xyz" cryptedText = "Dszqu uijt ufyu! Cux, yza" outputVariants = 0x402280 <_start>
, info variables
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(gdb) info variables All defined variables: File /usr/include/c++/10/bits/basic_string.h: 101: const std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::size_type std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >::npos; File /usr/include/c++/10/bits/stl_pair.h: 83: static const std::piecewise_construct_t std::piecewise_construct; File /usr/include/c++/10/iostream: 74: static std::ios_base::Init std::__ioinit; Non-debugging symbols: 0x00000000004002e8 __abi_tag 0x0000000000403000 _IO_stdin_used 0x00000000004031b8 typeinfo for std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > 0x00000000004031e0 typeinfo name for std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > --Type <RET> for more, q to quit, c to continue without paging--
info b
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(gdb) info b Num Type Disp Enb Address What 1 breakpoint keep y 0x0000000000402633 in Caesar::ChangeShift() at Caesar.h:31 breakpoint already hit 1 time 2 breakpoint keep y 0x00000000004026e3 in Caesar::Crypt(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) at Caesar.h:55 breakpoint already hit 1 time
whatis
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(gdb) whatis Caesar::shift type = int (gdb) whatis Caesar type = Caesar
, info address
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(gdb) info address Caesar::Crypt Symbol "Caesar::Crypt(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >)" is a function at address 0x4026be.
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Artikel ini tidak menyertakan beberapa perintah yang mudah dimengerti , misalnya: run, stop, exit, dll. Saya tidak sengaja menyebutkannya, karena artikel tersebut mencoba menyampaikan informasi yang mungkin tidak diketahui oleh pengguna GDB. Jika Anda memiliki saran bagaimana cara melengkapi artikel, saya dengan senang hati akan membaca komentarnya.