norlit-libc is a C library for x86 and x64.
norlit-libc is designed to conform to ISO C standard as well as those defined POSIX standard in the standard headers. norlit-libc do not intend to support other POSIX-specific headers, but may create stubs for them since they are not available in freestanding environment.
| Header | Status |
|---|---|
| <assert.h> | Implemented |
| <complex.h> | Not supported [1] |
| <ctype.h> | Implemented |
| <errno.h> | Implemented |
| <fenv.h> | Under consideration |
| <float.h> | Implemented [9] |
| <inttypes.h> | Implemented |
| <iso646.h> | Implemented |
| <limits.h> | Implemented (ISO C) |
| <locale.h> | Implemented |
| <math.h> | 28/69 (ISO C), 0/6 (POSIX) [4] |
| <setjmp.h> | Implemented (ISO C) 2/4 (POSIX) [8] |
| <signal.h> | Stub |
| <stdalign.h> | Implemented |
| <stdarg.h> | Implemented |
| <stdatomic.h> | Freestanding [2] |
| <stdbool.h> | Implemented |
| <stddef.h> | Implemented |
| <stdint.h> | Implemented |
| <stdio.h> | Implemented (ISO C) [5] 4/22 (POSIX) |
| <stdlib.h> | Implemented (ISO C) [3] 4/27 (POSIX) [7] |
| <stdnoreturn.h> | Implemented |
| <string.h> | Implemented |
| <tgmath.h> | Freestanding [2] |
| <threads.h> | Not supported [1] |
| <time.h> | Stub |
| <uchar.h> | Not supported [6] |
| <wchar.h> | Stub [6] |
| <wctype.h> | Not supported [6] |
| [1] | (1, 2) Conditional features are not in priority |
| [2] | (1, 2) In GCC it is available in freestanding environment, though C11 does not require it |
| [3] | system is a stub and will abort on call |
| [4] | Floating point numbers-related functions may have larger margin of error than expected |
| [5] | remove, rename, tmpfile and tmpnam not supported. POSIX extension to printf and scanf is not yet supported. |
| [6] | (1, 2, 3) Intended, but violate the standard |
| [7] | long double <-> string conversion is approximated with double <-> string conversion |
| [8] | Current there is only x86 support |
| [9] | FLT_ROUND and FLT_EVAL_METHOD are not implemented and will abort when used |
- Macros in errno.h and signal.h should be system dependent, extract them to include/sys in some way
- stdio.h
norlit-libc currently has no need for uchar and legacy wchar support. Related functions are defined but not implemented. Here is the list.
- <uchar.h>, <wchar.h> and <wctype.h>
- mblen, mbtowc, wctomb
- mbstowcs, wcstombs
- From <inttypes.h>: wcstoimax, wcstoumax
norlit-libc currently has no need for multi-threading, so thread-safe is not concerned. If future support for thread-safety is needed, convert all static variables to thread-local storage or add locks to them. Reentrancy support is also not considered currently.
norlit-libc currently has no need for locale, so only C/POSIX locale is supported. When implementing norlit-libc, functions use current locale will be redirected to *_l functions by first retrieving locale by uselocale((locale_t)0). *_l will do the job instead. To support multiple locale, simply reimplement all files under src/locale