Dirty Little Helper (DLH)

Set of tools including the most important syscall wrappers, library functions, and containers for creating a static standalone (freestanding) application - without libc / libstdc++ dependencies.

Usage

Simply run

make

to create the static library libdlh.a.

This library allows building a simple hello world example in file foo.cpp with the content

#include <dlh/stream/output.hpp>

int main() {
    cout << "Hallo Welt!" << endl;
    return 0;
}

by running

g++ -nodefaultlibs -nostdlib -nostdinc -I include -L. -ldlh -lgcc -o foo foo.cpp

Disabling additional language features with -fno-exceptions, -fno-stack-protector, and -mno-red-zone is recommended. In addition, libgcc should be included by adding -lgcc.

Legacy interface

By default, the legacy interface is omitted, e.g. due to the hiccup caused by the thread local errno variable, flat namespace for functions, etc... But in case you prefer a more similar interface to basic functions of libc/STL, compile DLH in LEGACY mode:

make LEGACY=1

and include the legacy folder in your project.

For example, a file bar.cpp with the contents

#include <iostream>

int main() {
    std::cout << "Hallo Welt!" << std::endl;
    return 0;
}

can be compiled using

g++ -nodefaultlibs -nostdlib -nostdinc -I include -I legacy -L. -ldlh -o bar bar.cpp

However, this still does not necessarily provide the same interface or all the functionality of their namesakes.

Compatibility

This project has a strong dependency on the compiler. Only certain features and platforms are supported. It is not intended for general-purpose use.

Author & License

Dirty Little Helper (DLH) is part of the Luci-project, which is being developed by Bernhard Heinloth of the Department of Computer Science 4 at Friedrich-Alexander-Universität Erlangen-Nürnberg and is available under the GNU Affero General Public License, Version 3 (AGPL v3).

Some files are borrowed from other projects:

• buddy allocator by Evan Wallace (MIT license)
• qsort by Valentin Ochs and Rich Felker from musl libc (MIT license)

Furthermore, the libc interface (especially system calls and their types) was strongly influenced by the GNU C library (glibc) and musl libc, hence certain methods might be very similar or identical.