net_rw.h

Lightweight low-level binary read/write helpers for C.

net_rw.h provides endian-safe primitive serialization functions for working with binary protocols, packet formats, file formats, embedded systems, SDR/radio protocols, and raw byte buffers.

The library is header-only, allocation-free, alignment-safe, and designed for explicit manual buffer management.

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Features

• Header-only implementation
• Little-endian serialization format
• Alignment-safe memory access using memcpy
• Portable fixed-width integer encoding
• IEEE754 float/double serialization
• No hidden state or allocations
• Minimal and low-overhead API
• Suitable for embedded and systems programming

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Supported Types

Unsigned Integers

• u8
• u16
• u32
• u64

Signed Integers

• i8
• i16
• i32
• i64

Floating Point

• f32
• f64

Raw Data

• byte arrays
• binary blobs

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Design Philosophy

net_rw.h is intentionally low-level.

The library only performs primitive binary serialization/deserialization operations.

It does NOT provide:

• automatic buffer management
• bounds checking
• stream abstractions
• offset tracking
• dynamic allocations
• protocol definitions

The caller is responsible for managing offsets, buffer sizes, and protocol structures.

Example:

uint8_t buffer[256];
size_t offset = 0;

write_u32(buffer + offset, 0x12345678);
offset += 4;

write_f32(buffer + offset, 3.14f);
offset += 4;

This explicit design keeps the library:

• lightweight
• deterministic
• flexible
• easy to integrate into low-level systems

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Endianness

All serialized values are encoded in little-endian format.

This ensures deterministic and portable binary encoding across architectures.

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Why Not Write Raw Structs?

Writing raw C structs directly to files or networks is often unsafe because of:

• compiler padding
• alignment differences
• endianness issues
• compiler/platform ABI differences

net_rw.h avoids these issues by explicitly encoding primitive values into raw byte buffers.

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Usage

Include

#include "net_rw.h"

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Writing Example

#include <stdio.h>
#include <stdint.h>
#include <string.h>

#include "net_rw.h"

int main(void)
{
    uint8_t buffer[256];
    size_t offset = 0;

    write_u32(buffer + offset, 0xABCD1234);
    offset += 4;

    write_u16(buffer + offset, 1337);
    offset += 2;

    write_f32(buffer + offset, 3.14f);
    offset += 4;

    write_bytes(buffer + offset, "hello", 5);
    offset += 5;

    return 0;
}

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Reading Example

#include <stdio.h>
#include <stdint.h>

#include "net_rw.h"

int main(void)
{
    uint8_t buffer[256];
    size_t offset = 0;

    uint32_t magic = read_u32(buffer + offset);
    offset += 4;

    uint16_t port = read_u16(buffer + offset);
    offset += 2;

    float value = read_f32(buffer + offset);
    offset += 4;

    return 0;
}

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Supported Functions

Write Functions

write_u8()
write_u16()
write_u32()
write_u64()

write_i8()
write_i16()
write_i32()
write_i64()

write_f32()
write_f64()

write_bytes()

Read Functions

read_u8()
read_u16()
read_u32()
read_u64()

read_i8()
read_i16()
read_i32()
read_i64()

read_f32()
read_f64()

read_bytes()

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Example Use Cases

net_rw.h is suitable for:

• TCP/UDP protocols
• SDR/radio packet formats
• custom binary protocols
• binary file formats
• game networking
• embedded firmware protocols
• IPC/shared memory
• serialization systems
• packet framing systems
• custom archive/container formats

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Safety Notes

The library assumes:

• valid pointers
• sufficient buffer size
• proper offset management by caller

No bounds checking is performed internally.

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Requirements

• C11 compatible compiler
• Compiler support for:
  • __builtin_memcpy
  • __builtin_bswap16
  • __builtin_bswap32
  • __builtin_bswap64

Tested with:

• GCC
• Clang

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License

MIT License