From 968738f9b133c8bda7d5ced178fd92f4445d791c Mon Sep 17 00:00:00 2001 From: Yaakov Selkowitz Date: Thu, 18 Dec 2014 14:55:21 +0000 Subject: Implement BSD/GNU unlocked stdio extensions. * libc/include/stdio.h (clearerr_unlocked, feof_unlocked, ferror_unlocked, fflush_unlocked, fgetc_unlocked, fgets_unlocked, fileno_unlocked, fputc_unlocked, fputs_unlocked, fread_unlocked, fwrite_unlocked): Declare. * libc/include/wchar.h (fgetwc_unlocked, fgetws_unlocked, fputwc_unlocked, fputws_unlocked, getwc_unlocked, getwchar_unlocked, putwc_unlocked, putwchar_unlocked): Declare. * libc/stdio/Makefile.am (ELIX_4_SOURCES): Add clearerr_u.c, feof_u.c, ferror_u.c, fflush_u.c, fgetc_u.c, fgets_u.c, fgetwc_u.c, fgetws_u.c, fileno_u.c, fputc_u.c, fputs_u.c, fputwc_u.c, fputws_u.c, fread_u.c, fwrite_u.c, getwc_u.c, getwchar_u.c, putwc_u.c, putwchar_u.c. Add necessary dependencies. * libc/stdio/Makefile.in: Regenerate. * libc/stdio/clearerr.c: Document unlocked variant. * libc/stdio/clearerr_u.c: New file. * libc/stdio/feof.c: Document unlocked variant. * libc/stdio/feof_u.c: New file. * libc/stdio/ferror.c: Document unlocked variant. * libc/stdio/ferror_u.c: New file. * libc/stdio/fflush.c: Add __IMPL_UNLOCKED__ overrides. Document unlocked variants. * libc/stdio/fflush_u.c: New file. * libc/stdio/fgetc.c: Document unlocked variants. * libc/stdio/fgetc_u.c: New file. * libc/stdio/fgets.c: Add __IMPL_UNLOCKED__ overrides. Document unlocked variants. * libc/stdio/fgets_u.c: New file. * libc/stdio/fgetwc.c: Document unlocked variants. (__fgetwc): Make non-static. * libc/stdio/fgetwc_u.c: New file. * libc/stdio/fgetws.c: Add __IMPL_UNLOCKED__ overrides. Document unlocked variants. * libc/stdio/fgetws_u.c: New file. * libc/stdio/fileno.c: Document unlocked variant. * libc/stdio/fileno_u.c: New file. * libc/stdio/fputc.c: Document unlocked variants. * libc/stdio/fputc_u.c: New file. * libc/stdio/fputs.c: Add __IMPL_UNLOCKED__ overrides. Document unlocked variants. * libc/stdio/fputs_u.c: New file. * libc/stdio/fputwc.c: Document unlocked variants. (__fputwc): Make non-static. * libc/stdio/fputwc_u.c: New file. * libc/stdio/fputws.c: Add __IMPL_UNLOCKED__ overrides. Document unlocked variants. * libc/stdio/fputws_u.c: New file. * libc/stdio/fread.c: Add __IMPL_UNLOCKED__ overrides. Document unlocked variants. * libc/stdio/fread_u.c: New file. * libc/stdio/fwrite.c: Add __IMPL_UNLOCKED__ overrides. Document unlocked variants. * libc/stdio/fwrite_u.c: New file. * libc/stdio/getwc_u.c: New file. * libc/stdio/getwchar.c: Document unlocked variants. * libc/stdio/getwchar_u.c: New file. * libc/stdio/local.h: Define locking macros as empty ifdef __IMPL_UNLOCKED__. (__fgetwc, __fputwc): Declare. * libc/stdio/putwc_u.c: New file. * libc/stdio/putwchar.c: Document unlocked variants. * libc/stdio/putwchar_u.c: New file. --- newlib/libc/stdio/fflush.c | 40 ++++++++++++++++++++++++++++++++++++---- 1 file changed, 36 insertions(+), 4 deletions(-) (limited to 'newlib/libc/stdio/fflush.c') diff --git a/newlib/libc/stdio/fflush.c b/newlib/libc/stdio/fflush.c index 2286e38..a4e639e 100644 --- a/newlib/libc/stdio/fflush.c +++ b/newlib/libc/stdio/fflush.c @@ -17,19 +17,32 @@ /* FUNCTION -<>---flush buffered file output +<>, <>---flush buffered file output INDEX fflush INDEX + fflush_unlocked +INDEX _fflush_r +INDEX + _fflush_unlocked_r ANSI_SYNOPSIS #include int fflush(FILE *<[fp]>); + #define _BSD_SOURCE + #include + int fflush_unlocked(FILE *<[fp]>); + + #include int _fflush_r(struct _reent *<[reent]>, FILE *<[fp]>); + #define _BSD_SOURCE + #include + int _fflush_unlocked_r(struct _reent *<[reent]>, FILE *<[fp]>); + DESCRIPTION The <> output functions can buffer output before delivering it to the host system, in order to minimize the overhead of system calls. @@ -45,9 +58,18 @@ descriptor, set the position of the file descriptor to match next unread byte, useful for obeying POSIX semantics when ending a process without consuming all input from the stream. -The alternate function <<_fflush_r>> is a reentrant version, where the -extra argument <[reent]> is a pointer to a reentrancy structure, and -<[fp]> must not be NULL. +<> is a non-thread-safe version of <>. +<> may only safely be used within a scope +protected by flockfile() (or ftrylockfile()) and funlockfile(). This +function may safely be used in a multi-threaded program if and only +if they are called while the invoking thread owns the (FILE *) +object, as is the case after a successful call to the flockfile() or +ftrylockfile() functions. If threads are disabled, then +<> is equivalent to <>. + +The alternate functions <<_fflush_r>> and <<_fflush_unlocked_r>> are +reentrant versions, where the extra argument <[reent]> is a pointer to +a reentrancy structure, and <[fp]> must not be NULL. RETURNS <> returns <<0>> unless it encounters a write error; in that @@ -57,6 +79,8 @@ PORTABILITY ANSI C requires <>. The behavior on input streams is only specified by POSIX, and not all implementations follow POSIX rules. +<> is a BSD extension also provided by GNU libc. + No supporting OS subroutines are required. */ @@ -65,6 +89,12 @@ No supporting OS subroutines are required. #include #include "local.h" +#ifdef __IMPL_UNLOCKED__ +#define _fflush_r _fflush_unlocked_r +#define fflush fflush_unlocked +#endif + +#ifndef __IMPL_UNLOCKED__ /* Flush a single file, or (if fp is NULL) all files. */ /* Core function which does not lock file pointer. This gets called @@ -217,6 +247,8 @@ _DEFUN(__sflushw_r, (ptr, fp), } #endif +#endif /* __IMPL_UNLOCKED__ */ + int _DEFUN(_fflush_r, (ptr, fp), struct _reent *ptr _AND -- cgit v1.1