lighttransport / nanolibc

Nanoscale libc

nanolibc, Nanoscale libc implementation

nanolibc is a small subset of standard C library(libc) implementation.

nanolibc's primal usage is for embedded C programs, secure C/C++ programs, multithreaded C/C++ programs, and adding cross-platform JIT compilation of C/C++ application to your C/C++ application(MSVC, Linux, macOS)

Design direction

• May not implement legacy, unsecure functions(fopen, wordexp, ...)
• No global state as much as possible(e.g. no global error code)
• Functions withi interacts with system will be not implemented or no-op(e.g. system(), abort(), sbrk(), execve())

Requirements

• C11 compiler

Supported platform

• Windows(MSVCRT/uCRT) : Most of libc functions are deligated to the function in MSVCRT/uCRT.
• Linux : Use musl implementation, llvm libc.
• macOS : T.B.D.

Supported functions

C90

• nanoassert.h
  • assert
• nanoctype.h
  • isalnum
  • isalpha
  • isblank
  • iscntrl
  • isdigit
  • isgraph
  • islower
  • isprint
  • ispunct
  • isspace
  • isupper
  • isxdigit
• nanoerrono.h
  • errno
• nanofloat.h
• nanoiso646.h
• nanolimits.h
• nanolocale.h
• nanosetjmp.h
• nanosignal.h
• nanostdarg.h
• nanostddef.h
• nanostdio.h
  • remove
  • rename
  • tmpfile
  • tmpnam
  • fclose
  • fflush
  • fopen
  • freopen
  • setbuf
  • setvbuf
  • fprintf
  • fscanf
  • printf
  • scanf
  • snprintf
  • sprintf
  • sscanf
  • vfprintf
  • vfscanf
  • vprintf
  • vscanf
  • vsnprintf
  • vsprintf
  • vsscanf
  • fgetc
  • fgets
  • fputc
  • fputs
  • getc
  • getchar
  • gets
  • putc
  • putchar
  • puts
  • ungetc
  • fread
  • fwrite
  • fgetpos
  • fseek
  • fsetpos
  • ftell
  • rewind
  • clearerr
  • feof
  • ferror
  • perror
• nanostdlib.h
  • atof
  • atoi
  • atol
  • atoll(C++11)
  • strtod
  • strtof(C++11)
  • strtol
  • strtold(C++11)
  • strtoll(C++11)
  • strtoul
  • strtoull(C++11)
• nanostring.h
  • memcpy
  • memmove
  • strcpy
  • strncpy
  • strcat
  • strncat
  • memcmp
  • strcmp
  • strcoll
  • strncmp
  • strxfrm
  • memchr
  • strchr
  • strcspn
  • strpbrk
  • strchr
  • strspn
  • strstr
  • strtok
  • memset
  • sterror
  • strlen
  • NULL
• nanotime.h

C11

• fenv.h
• inttypes.h
• stdbool.h
• stdint.h
• tgmath.h
• uchar.h

Wide characters

• wchar.h
• wctype.h

libm

T.B.W.

Build samples/tests

nanolibc uses meson to build samples/tests. Please install meson(https://mesonbuild.com/) and ninjaa(https://ninja-build.org/)

Linux

Edit scripts/bootstrap-linux.sh, then

$ ./scripts/bootstrap-linux.sh
$ cd build
$ ninja

TODO

Support compilation on C89 compiler.

License

MIT license.

Third party licenses

musl : MIT license.