edp

A C89 standard compliant, single header, nostdlib (no C Standard Library) Executable Data Packager (EDP).

For more information please look at the "edp.h" file or take a look at the "examples" or "tests" folder.

Warning

THIS PROJECT IS A WORK IN PROGRESS! ANYTHING CAN CHANGE AT ANY MOMENT WITHOUT ANY NOTICE! USE THIS PROJECT AT YOUR OWN RISK!

EDP lets you append arbitrary data to an executable and access it at runtime, all without relying on the C Standard Library.

Features

• C89 compliant — portable and legacy-friendly
• Single-header API — just include edp.h
• nostdlib — no dependency on the C Standard Library
• Minimal binary size — optimized for small executables
• Cross-platform — Windows, Linux, and more (WIP)
• Strict compilation — built with aggressive warnings & safety checks

1. Get EDP

Clone the repository or download the standalone files:

git clone https://github.com/nickscha/edp.git

The project consists of two main components:

File	Purpose
edp.c	Standalone nostdlib appender — append arbitrary data to an executable
edp.h	Loader API — read the appended data directly at runtime

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2. Building the Appender (edp.c)

The appender is freestanding and nostdlib. Compile using Clang or GCC with strict flags:

set DEF_COMPILER_FLAGS=-mconsole -march=native -mtune=native -std=c89 -pedantic -nodefaultlibs -nostdlib -mno-stack-arg-probe -Xlinker /STACK:0x100000,0x100000 ^
-fno-builtin -ffreestanding -fno-asynchronous-unwind-tables -fuse-ld=lld ^
-Wall -Wextra -Werror -Wvla -Wconversion -Wdouble-promotion -Wsign-conversion -Wuninitialized -Winit-self ^
-Wunused -Wunused-function -Wunused-macros -Wunused-parameter -Wunused-value -Wunused-variable -Wunused-local-typedefs

set DEF_FLAGS_LINKER=-lkernel32
cc -s -Os %DEF_COMPILER_FLAGS% edp.c -o edp.exe %DEF_FLAGS_LINKER%

Or download prebuilt binaries from
GitHub Actions → Latest Artifacts.

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3. Appending Data to an Executable

Once compiled, append arbitrary data:

edp.exe my_program.exe my_payload.bin

This appends my_payload.bin to the end of my_program.exe.
The data can then be accessed at runtime using edp.h.

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4. Loading Appended Data (edp.h)

Here’s how you load the embedded payload:

#include "edp.h"  /* Executable Data Packager */

int main(void) {
    void *payload = 0;
    unsigned int payload_size = 0;

    if (!edp_data_load(&payload, &payload_size)) {
        /* No data was appended */
        return 1;
    }

    /* Use payload & payload_size here */

    /* Free memory after use */
    edp_data_free(payload);

    return 0;
}

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Motivation

EDP exists to give developers a minimalistic, reliable, and portable solution for:

• Embedding configuration, assets, or metadata inside executables
• Accessing that data without external files
• Operating without the C Standard Library

This approach is especially useful for:

• Self-contained tools
• Licensing & authentication systems
• Bootloaders & embedded systems
• Portable cross-platform executables
• Assets

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"nostdlib" Motivation & Purpose

nostdlib is a lightweight, minimalistic approach to C development that removes dependencies on the standard library. The motivation behind this project is to provide developers with greater control over their code by eliminating unnecessary overhead, reducing binary size, and enabling deployment in resource-constrained environments.

Many modern development environments rely heavily on the standard library, which, while convenient, introduces unnecessary bloat, security risks, and unpredictable dependencies. nostdlib aims to give developers fine-grained control over memory management, execution flow, and system calls by working directly with the underlying platform.

Benefits

Minimal overhead

By removing the standard library, nostdlib significantly reduces runtime overhead, allowing for faster execution and smaller binary sizes.

Increased security

Standard libraries often include unnecessary functions that increase the attack surface of an application. nostdlib mitigates security risks by removing unused and potentially vulnerable components.

Reduced binary size

Without linking to the standard library, binaries are smaller, making them ideal for embedded systems, bootloaders, and operating systems where storage is limited.

Enhanced performance

Direct control over system calls and memory management leads to performance gains by eliminating abstraction layers imposed by standard libraries.

Better portability

By relying only on fundamental system interfaces, nostdlib allows for easier porting across different platforms without worrying about standard library availability.