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Gurigraphics
Gurigraphics

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Embedding Files in an Executable - Linux/WSL2 - Part 1

#c #cpp #wsl2 #linux

1) Create data.txt

echo "Hello World" > data.txt
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2) Convert data.txt to data.o

objcopy -I binary -O elf64-x86-64 -B i386 data.txt data.o
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3) Get Symbols

hexdump -C data.o
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000000b0 00 5f 62 69 6e 61 72 79 5f 64 61 74 61 5f 74 78 |._binary_data_tx| 000000c0 74 5f 73 74 61 72 74 00 5f 62 69 6e 61 72 79 5f |t_start._binary_| 000000d0 64 61 74 61 5f 74 78 74 5f 65 6e 64 00 5f 62 69 |data_txt_end._bi| 000000e0 6e 61 72 79 5f 64 61 74 61 5f 74 78 74 5f 73 69 |nary_data_txt_si| 000000f0 7a 65 00 00 2e 73 79 6d 74 61 62 00 2e 73 74 72 |ze...symtab..str| 00000100 74 61 62 00 2e 73 68 73 74 72 74 61 62 00 2e 64 |tab..shstrtab..d| 00000110 61 74 61 00 00 00 00 00 00 00 00 00 00 00 00 00 |ata.............| 00000120 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
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_binary_data_txt_start _binary_data_txt_end _binary_data_txt_size
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4) Create main.c

#include <stdio.h>  extern char _binary_data_txt_start; extern char _binary_data_txt_end; int main(){ char* p = &_binary_data_txt_start; while ( p != &_binary_data_txt_end ) putchar(*p++); return 0; }
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5) Compile

gcc main.c data.o -o myprogram
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6) Run

./myprogram
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Compile windows exe

1) Install

sudo apt install gcc-mingw-w64-i686-win32 sudo apt install g++-mingw-w64-i686-win32
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2) Test

i686-w64-mingw32-gcc --version i686-w64-mingw32-g++ --version
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3) Convert data.txt to data.o

i686-w64-mingw32-objcopy -I binary -O pe-i386 -B i386 data.txt data.o
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4) Get Symbols

hexdump -C data.o
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00000070 30 00 00 00 0c 00 00 00 ff ff 00 00 02 00 46 00 |0.............F.| 00000080 00 00 5f 62 69 6e 61 72 79 5f 64 61 74 61 5f 74 |.._binary_data_t| 00000090 78 74 5f 73 74 61 72 74 00 5f 62 69 6e 61 72 79 |xt_start._binary| 000000a0 5f 64 61 74 61 5f 74 78 74 5f 65 6e 64 00 5f 62 |_data_txt_end._b| 000000b0 69 6e 61 72 79 5f 64 61 74 61 5f 74 78 74 5f 73 |inary_data_txt_s| 000000c0 69 7a 65 00
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5) Remove initial underscores

binary_data_txt_start binary_data_txt_end binary_data_txt_size
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6) Create main.c or main.cpp

#include <stdio.h>  extern char binary_data_txt_start; extern char binary_data_txt_end; int main(){ char* p = &binary_data_txt_start; while ( p != &binary_data_txt_end ) putchar(*p++); return 0; }
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#include <iostream>  extern char binary_data_txt_start; extern char binary_data_txt_end; int main(){ char* p = &binary_data_txt_start; while (p != &binary_data_txt_end) std::cout << *p++; return 0; }
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7) Compile

i686-w64-mingw32-gcc main.c data.o -o main.exe or i686-w64-mingw32-g++ main.cpp data.o -o main.exe
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Part 2

https://dev.to/gurigraphics/embedding-files-in-an-executable-windows-part-2-3gja

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