libk  Check-in [8e0015144e]

libk's goals are far-reaching, and suggestions are welcome. note however that libk is *not* intended to be a kitchen-sink library like libiberty. it's meant to do one thing, and to it well: to provide an easy- and pleasant-to-use foundation for modern open source projects. below is a list of some of the project's major goals.

 1. **IO.** libc's basic input/output mechanisms are dreadful, built at entirely the wrong level of abstraction. libk is intended to make many more primitives available to the user, and offer a sliding scale of abstraction so libk is suitable for a wide range of needs.
 2. **file manipulation.** libc's file manipulation primitives are a relic of a bygone age and in dire need of upgrading.
 3. **terminal manipulation.** libc has no provision for simple output formatting, a task that requires a combination of ANSI codes and in some cases pty manipulation with POSIX APIs, both of which are somewhat dark wizardry. this situation forces many innocent coders to drag in the entire unholy bulk of the aptly named library `ncurses`, much of whose code has been utterly obsolete for the last twenty years and whose API is one of the most singularly hateful ones in existence. libk therefore should offer a simple, straightforward way to do gracefully-degrading terminal sorcery.
 0. **tooling.** libk is intended as more than just a library. it's also intended to work with some basic tooling to automate tasks that current binary tooling is inadequate for -- for instance, embedding binary data into a program binary. (see module [kgraft](kgraft))
 0. **modularity.** libk is not part of the C specification and it isn't always going to be practical for developers to expect the entire library to be present on the end-user's computer. so libk is designed to be usable in many different ways -- as a traditional lirbary, as a static library, in full form or with only components needed by the developer, to be distributed either on its own or as part of an binary.
 0. **compatibility.** code that links against libk should be able to compile and run on any operating system. in the ideal case (Linux or FreeBSD) it will be able to do so without touching any other system libraries; for less ideal environments like Windows, libk will when necessary abstract over system libraries or libc itself.

## naming conventions

one of the most frustrating things about libc is its complete and total *lack* of a naming convention. in C, every function and global is injected into a single global namespace, including macros. this means that every libc header you include scatters words all over that namespace, potentially clobbering your function with a macro!

libk is designed to fix this (in hindsight) glaring error.

however, a common problem with libraries is the proliferation of inordinately long and hard-to-type function names such as `SuperWidget_Widget_Label_Font_Set()`. this may be tolerable in IDEs with robust auto-complete or when referencing a highly-specific, sparsely-used library; it is however completely intolerable in the case of a core library with heavily used functionality.

therefore, libk uses two slightly different naming conventions: the **short** convention, for core functions the user will call frequently, and the **full** convention, for less-commonly used functions. the inconvenience of remembering which is which will hopefully be outweighed by the keystrokes (and bytes) saved.

in the **full** convention, a function's name is prefixed with its module name followed by an underscore. thus, `kfile/open.c` will be invoked as `kfile_open()`.

in the **short** convention, the function name is prefixed by the letter `k` followed by the module's "glyph" -- a one- or two-letter sequence that represents the module, usually the first one or two characters. therefore, `kio/write.c` is invoked as `kiowrite`.

................................................................................

#### arches

these atoms will be used to reference particular system architectures. these will mostly be used in the filenames of assembly code.

## macros

libk will not in any circumstance use macros to encode magic numbers, instead using typedef'd enums. all libk macros begin with the uppercase letter `K` -- e.g. `Kmacro`. macros that can be defined by the user to alter the behavior of the api should begin with `KF` if they are on/off flags, or `KV` otherwise. **macros should only be defined if the flag `KFclean` is *not* defined.**

## languages

libk uses only three languages: C (\*.c, \*.h), yasm (\*.s), and make (makefile).

other assemblers will probably be necessary for the more exotic targets, however.

## repository structure

libk uses a rigorously directory structure for code, and deviations from this structure will not be tolerated without extremely good reason.

all libk code is dispersed into modules: `kcore` for internals, `kio` for I/O, `kgraft` for binary packing, etc. each module has a folder in the root directory. (libk does not have submodules.) inside each module's directory should be a header with the same name as the module and a folder for each operating system (see **naming conventions** above).

each function should be kept in a separate file within its module's directory. when OS or architecture-specific code is needed, the file's name should be a list of one or more of the fields [arch, OS, bits, format] separated by a `.` -- for instance, the 32-bit x86 haiku version of a function called `write` defined in assembly would be named `write.haiku.x86.32.s`. however, if a function has an extraordinarily large number of versions, they may instead be stored in a folder with the same name as the function.

each module should have a header named the same thing as the module except without the `k` prefix. (e.g. the header for `kio` is `kio/io.h`) located in its folder. this is the header that the end-user will be importing, and should handle any user-defined flags to present the API the user has selected.

each module directory should contain a makefile that can build that module. see **makefiles** below. all makefiles should be named `makefile` (**not** `Makefile`).

each module should contain a markdown file. this file's name should be the name of the parent directory suffixed with `.md`; for instance, `kterm` should contain the file `kterm/kterm.md`. this file should document the module as thoroughly as possible 

libk's goals are far-reaching, and suggestions are welcome. note however that libk is *not* intended to be a kitchen-sink library like libiberty. it's meant to do one thing, and to it well: to provide an easy- and pleasant-to-use foundation for modern open source projects. below is a list of some of the project's major goals.

 1. **IO.** libc's basic input/output mechanisms are dreadful, built at entirely the wrong level of abstraction. libk is intended to make many more primitives available to the user, and offer a sliding scale of abstraction so libk is suitable for a wide range of needs.
 2. **file manipulation.** libc's file manipulation primitives are a relic of a bygone age and in dire need of upgrading.
 3. **terminal manipulation.** libc has no provision for simple output formatting, a task that requires a combination of ANSI codes and in some cases pty manipulation with POSIX APIs, both of which are somewhat dark wizardry. this situation forces many innocent coders to drag in the entire unholy bulk of the aptly named library `ncurses`, much of whose code has been utterly obsolete for the last twenty years and whose API is one of the most singularly hateful ones in existence. libk therefore should offer a simple, straightforward way to do gracefully-degrading terminal sorcery.
 0. **tooling.** libk is intended as more than just a library. it's also intended to work with some basic tooling to automate tasks that current binary tooling is inadequate for -- for instance, embedding binary data into a program binary. (see module [kgraft](kgraft))
 0. **modularity.** libk is not part of the C specification and it isn't always going to be practical for developers to expect the entire library to be present on the end-user's computer. so libk is designed to be usable in many different ways -- as a traditional library, as a static library, in full form or with only components needed by the developer, to be distributed either on its own or as part of a binary.
 0. **compatibility.** code that links against libk should be able to compile and run on any operating system. in the ideal case (Linux or FreeBSD) it will be able to do so without touching any other system libraries; for less ideal environments like Windows, libk will when necessary abstract over system libraries or libc itself.

## naming conventions

one of the most frustrating things about libc is its complete and total *lack* of a naming convention. in C, every function and global is injected into a single global namespace, including macros. this means that every libc header you include scatters words all over that namespace, potentially clobbering your function with a macro!

libk is designed to fix this (in hindsight) glaring error.

however, a common problem with libraries is the proliferation of inordinately long and hard-to-type function names such as `SuperWidget_Widget_Label_Font_Size_Set()`. this may be tolerable in IDEs with robust auto-complete or when referencing a highly-specific, sparsely-used library; it is however completely intolerable in the case of a core library with heavily used functionality.

therefore, libk uses two slightly different naming conventions: the **short** convention, for core functions the user will call frequently, and the **full** convention, for less-commonly used functions. the inconvenience of remembering which is which will hopefully be outweighed by the keystrokes (and bytes) saved.

in the **full** convention, a function's name is prefixed with its module name followed by an underscore. thus, `kfile/open.c` will be invoked as `kfile_open()`.

in the **short** convention, the function name is prefixed by the letter `k` followed by the module's "glyph" -- a one- or two-letter sequence that represents the module, usually the first one or two characters. therefore, `kio/write.c` is invoked as `kiowrite`.

................................................................................

#### arches

these atoms will be used to reference particular system architectures. these will mostly be used in the filenames of assembly code.

## macros

libk will not in any circumstance use macros to encode magic numbers, instead using typedef'd enums. all libk macros begin with the uppercase letter `K` -- e.g. `Kmacro`. macros that can be defined by the user to alter the behavior of the api should begin with `KF` if they are on/off flags, or `KV` otherwise. **macros should only be defined by the libk headers if the flag `KFclean` is *not* defined at the time of inclusion.**

## languages

libk uses only three languages: C (\*.c, \*.h), yasm (\*.s), and make (makefile).

other assemblers will probably be necessary for the more exotic targets, however.

## repository structure

libk uses a strict directory structure for code, and deviations from this structure will not be tolerated without extremely good reason.

all libk code is dispersed into modules: `kcore` for internals, `kio` for I/O, `kgraft` for binary packing, etc. each module has a folder in the root directory. (libk does not have submodules.) inside each module's directory should be a header with the same name as the module (see **naming conventions** above).

each function should be kept in a separate file within its module's directory. when OS or architecture-specific code is needed, the file's name should be a list of one or more of the fields [arch, OS, bits, format] separated by a `.` -- for instance, the 32-bit x86 haiku version of a function called `write` defined in assembly would be named `write.x86.haiku.32.s`. however, if a function has an extraordinarily large number of versions, they may instead be stored in a folder with the same name as the function.

each module should have a header named the same thing as the module except without the `k` prefix. (e.g. the header for `kio` is `kio/io.h`) located in its folder. this is the header that the end-user will be importing, and should handle any user-defined flags to present the API the user has selected.

each module directory should contain a makefile that can build that module. see **makefiles** below. all makefiles should be named `makefile` (**not** `Makefile`).

each module should contain a markdown file. this file's name should be the name of the parent directory suffixed with `.md`; for instance, `kterm` should contain the file `kterm/kterm.md`. this file should document the module as thoroughly as possible