This file describes the implementation status and some notes; information is
taken from the C99 standard (ISO/IEC 9899:1999), section 7 ("Library").
# Notes for implementers
7.1.2§6:
Use (extern) in all function prototypes
7.1.3§1:
Only expose standard identifiers; anything else might be defined as a macro.
Make sure every argument name, internal function name, etc. starts with
either "__" or "_X" (where X is any uppercase letter)
7.1.4§1:
Always give a function even if there is a macro definition, so that the
address of the function can be taken; don't rely on the macro being defined,
as the user can remove it except in some special cases
String functions (mainly in <string.h>) can use 4-byte accesses, and in doing
so read up to 3 bytes after the end of the string if it is not padded (which
malloc'd strings and literal strings both are, leaving only stack-allocated and
statically-allocated ones). This allows important speed optimizations. The
extra access cannot trigger memory protection because there is no valid memory
less than 4 bytes before the end of any protection region. The extra access
might trigger the UBC in very specific scenarios, but we don't really care.
# Status
In this file, every definition is classified in one of several implementation
statuses. There are 5 stages that every definition should go through.
TODO: Function/symbol/macro is not implemented/defined
BDEPS(...): Function/symbol/macro needs ... to build
LDEPS(...): Function/symbol/macro needs ... to link
TEST: Function/symbol/macro needs to be tested
-: Function/symbol/macro is defined, builds, links, and is tested
7.2 <assert.h>
7.2.1 assert LDEPS(fprintf,stderr)
7.3 <complex.h> => OpenLibm
7.4 <ctype.h>
7.4.1 is* -
7.4.2 to* -
7.5 <errno.h>
7.5.2 EDOM, EILSEQ, ERANGE -
7.6 <fenv.h> => OpenLibm
7.7 <float.h> => GCC
7.8 <inttypes.h>
7.8.1 PRI* macros -
7.8.1 SCN* macros -
7.8.2.1 imaxabs -
7.8.2.2 imaxdiv -
7.8.2.3 strtoimax, strtoumax -
7.8.2.4 wcstoimax, wcstoumax TODO
7.9 <iso646.h> => GCC
7.10 <limits.h> => GCC
7.11 <locale.h>
7.11.1 setlocale TEST
7.11.2 localeconv TEST
7.12 <math.h> => OpenLibm
7.13 <setjmp.h>
7.13.1 setjmp -
7.13.2 longjmp -
7.14 <signal.h>
7.14.1.1 signal -
7.14.1.2 raise -
7.15 <stdarg.h> => GCC
7.16 <stdbool.h> => GCC
7.17 <stddef.h> => GCC
7.18 <stdint.h> => GCC
7.19 <stdio.h>
7.19.1 Introduction - (no wide-oriented streams *)
7.19.1 stdin, stdout, stderr -
7.19.4.1 remove TEST
7.19.4.2 rename TODO
7.19.4.3 tmpfile TODO
7.19.4.4 tmpnam TODO
7.19.5.1 fclose -
7.19.5.2 fflush - (fflush(NULL) not supported yet)
7.19.5.3 fopen -
(EXT) fdopen -
7.19.5.4 freopen -
7.19.5.5 setbuf -
7.19.5.6 setvbuf -
7.19.6.1 fprintf -
7.19.6.2 fscanf TODO
7.19.6.3 printf -
7.19.6.4 scanf TODO
7.19.6.5 snprintf -
7.19.6.6 sprintf -
7.19.6.7 sscanf TODO
7.19.6.8 vfprintf -
7.19.6.9 vfscanf TODO
7.19.6.10 vprintf -
7.19.6.11 vscanf TODO
7.19.6.12 vsnprintf -
7.19.6.13 vsprintf -
7.19.6.14 vsscanf TODO
(EXT) asprintf -
(EXT) vasprintf -
(EXT) dprintf -
(EXT) vdprintf -
7.19.7.1 fgetc -
7.19.7.2 fgets -
7.19.7.3 fputc -
7.19.7.4 fputs -
7.19.7.5 getc -
7.19.7.6 getchar -
7.19.7.7 gets -
7.19.7.8 putc -
7.19.7.9 putchar -
7.19.7.10 puts -
7.19.7.11 ungetc -
(EXT) getline -
(EXT) getdelim -
7.19.8.1 fread -
7.19.8.2 fwrite -
7.19.9.1 fgetpos -
7.19.9.2 fseek -
7.19.9.3 fsetpos -
7.19.9.4 ftell -
7.19.9.5 rewind -
7.19.10.1 clearerr -
7.19.10.2 feof -
7.19.10.3 ferror -
7.19.10.4 perror -
7.20 <stdlib.h>
7.20 MB_CUR_MAX TODO
7.20.1.1 atof -
7.20.1.2 atoi, atol, atoll -
7.20.1.3 strtod, strtof, strtold -
7.20.1.4 strtol, strtoul -
7.20.1.4 strtoll, strtoull -
7.20.2.1 rand -
7.20.2.2 srand -
7.20.3.1 calloc -
7.20.3.2 free - (gint)
7.20.3.3 malloc - (gint)
7.20.3.4 realloc - (gint)
7.20.4.1 abort - (stream flushing/closing/etc?)
7.20.4.2 atexit TODO
7.20.4.3 exit - (stream flushing/closing/etc?)
7.20.4.4 _Exit - (gint)
7.20.4.5 getenv TODO
7.20.4.6 system TODO
7.20.5.1 bsearch TODO
7.20.5.2 qsort TEST
7.20.6.1 abs, labs, llabs -
7.20.6.2 div, ldiv, lldiv -
7.20.7 Multibyte/wide char conv TODO
7.20.8 Multibyte/wide string conv TODO
7.21 <string.h>
7.21.2.1 memcpy -
7.21.2.2 memmove - (Unoptimized: byte-by-byte)
7.21.2.3 strcpy -
7.21.2.4 strncpy -
7.21.3.1 strcat -
7.21.3.2 strncat -
7.21.4.1 memcmp -
7.21.4.2 strcmp -
7.21.4.3 strcoll -
7.21.4.4 strncmp -
7.21.4.5 strxfrm -
7.21.5.1 memchr -
7.21.5.2 strchr -
7.21.5.3 strcspn -
7.21.5.4 strpbrk -
7.21.5.5 strrchr -
7.21.5.6 strspn -
7.21.5.7 strstr -
7.21.5.8 strtok -
7.21.6.1 memset -
7.21.6.2 strerror -
7.21.6.3 strlen -
(EXT) strnlen -
(EXT) strchrnul -
(EXT) strcasestr -
(EXT) strcasecmp -
(EXT) strncasecmp -
(EXT) strdup -
(EXT) strndup -
(EXT) memrchr - (Unoptimized: byte-by-byte)
7.22 <tgmath.h> => GCC
7.23 <time.h>
7.23.2.1 clock -
7.23.2.2 difftime -
7.23.2.3 mktime - (DST flag ignored)
7.23.2.4 time -
7.23.3.1 asctime -
7.23.3.2 ctime -
7.23.3.3 gmtime -
7.23.3.4 localtime - (No timezones; same as gmtime)
7.23.3.5 strftime - (No %g, %G, %U, %V, %W, %z, %Z)
7.24 <wchar.h> TODO (not a priority)
7.25 <wctype.h> TODO (not a priority)
# Supporting locales
What if we wanted to support more locales?
-> Need to a mechanism to supply the raw information, similar to the text files
in /usr/share/i18n/locales
-> Implement setlocale() and localeconv() properly (not hard)
-> Probably support nl_langinfo(), which is much better than localeconv()
-> Fix the "TODO: locale: ..." messages wherever assumptions on the locale are
made in the code
-> Properly implement strcoll() and strxfrm()
-> Add support in strftime()
# Supporting text and binary files (newline translation)
Because of 7.19.2§1.223 we don't need to support newline translation.
# Support wide-oriented streams
This requires all the wide-char functions but also updating fpos_t to be a
structure with at least some mbstate_t member (7.19.2§6).
I really don't want to do that. Use multi-byte functions with UTF-8.
# Supporting timezones
-> Update localtime()
-> Add some timezone API