From 458e3bbc5d35a0c476859815f3b7cd8bb7f49b13 Mon Sep 17 00:00:00 2001 From: ngie Date: Sun, 13 Dec 2015 06:54:53 +0000 Subject: [PATCH] MFstable/10 r291602: MFC r285140: r285140 (by oshogbo): Add fdclose(3) function. This function is equivalent to fclose(3) function except that it does not close the underlying file descriptor. fdclose(3) is step forward to make FILE structure private. Reviewed by: wblock, jilles, jhb, pjd Approved by: pjd (mentor) Differential Revision: https://reviews.freebsd.org/D2697 git-svn-id: svn://svn.freebsd.org/base/stable/9@292154 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f --- include/stdio.h | 1 + lib/libc/stdio/Symbol.map | 4 ++ lib/libc/stdio/fclose.3 | 82 +++++++++++++++++++++++++++++++-------- lib/libc/stdio/fclose.c | 75 +++++++++++++++++++++++++++++------ 4 files changed, 135 insertions(+), 27 deletions(-) diff --git a/include/stdio.h b/include/stdio.h index 4a07990c6..39dacd061 100644 --- a/include/stdio.h +++ b/include/stdio.h @@ -396,6 +396,7 @@ int (dprintf)(int, const char * __restrict, ...); int asprintf(char **, const char *, ...) __printflike(2, 3); char *ctermid_r(char *); void fcloseall(void); +int fdclose(FILE *, int *); char *fgetln(FILE *, size_t *); const char *fmtcheck(const char *, const char *) __format_arg(2); int fpurge(FILE *); diff --git a/lib/libc/stdio/Symbol.map b/lib/libc/stdio/Symbol.map index 538b29aac..15db18e1d 100644 --- a/lib/libc/stdio/Symbol.map +++ b/lib/libc/stdio/Symbol.map @@ -160,6 +160,10 @@ FBSD_1.3 { open_wmemstream; }; +FBSD_1.4 { + fdclose; +}; + FBSDprivate_1.0 { _flockfile; _flockfile_debug_stub; diff --git a/lib/libc/stdio/fclose.3 b/lib/libc/stdio/fclose.3 index 883aa108e..596ee3db0 100644 --- a/lib/libc/stdio/fclose.3 +++ b/lib/libc/stdio/fclose.3 @@ -1,5 +1,6 @@ -.\" Copyright (c) 1990, 1991, 1993 -.\" The Regents of the University of California. All rights reserved. +.\" Copyright (c) 1990, 1991, 1993 The Regents of the University of California. +.\" Copyright (c) 2015 Mariusz Zaborski +.\" All rights reserved. .\" .\" This code is derived from software contributed to Berkeley by .\" Chris Torek and the American National Standards Committee X3, @@ -32,11 +33,12 @@ .\" @(#)fclose.3 8.1 (Berkeley) 6/4/93 .\" $FreeBSD$ .\" -.Dd April 22, 2006 +.Dd July 4, 2015 .Dt FCLOSE 3 .Os .Sh NAME .Nm fclose , +.Nm fdclose , .Nm fcloseall .Nd close a stream .Sh LIBRARY @@ -45,6 +47,8 @@ .In stdio.h .Ft int .Fn fclose "FILE *stream" +.Ft int +.Fn fdclose "FILE *stream" "int *fdp" .Ft void .Fn fcloseall void .Sh DESCRIPTION @@ -59,36 +63,77 @@ first, using .Xr fflush 3 . .Pp The +.Fn fdclose +function is equivalent to +.Fn fclose +except that it does not close the underlying file descriptor. +If +.Fa fdp +is not +.Dv NULL , +the file descriptor will be written to it. +If the +.Fa fdp +argument will be different then NULL the file descriptor will be returned in it, +If the stream does not have an associated file descriptor, +.Fa fdp +will be set to -1. +This type of stream is created with functions such as +.Xr fmemopen 3 , +.Xr funopen 3 , +or +.Xr open_memstream 3 . +.Pp +The .Fn fcloseall function calls .Fn fclose on all open streams. .Sh RETURN VALUES -Upon successful completion 0 is returned. +.Fn fcloseall +does not return a value. +.Pp +Upon successful completion the +.Fn fclose +and +.Fn fdclose +functions return 0. Otherwise, .Dv EOF is returned and the global variable .Va errno is set to indicate the error. -In either case no further access to the stream is possible. .Sh ERRORS +.Fn fdclose +fails if: +.Bl -tag -width Er +.It Bq Er EOPNOTSUPP +The stream does not have an associated file descriptor. +.El +.Pp The .Fn fclose -function -may also fail and set +and +.Fn fdclose +functions may also fail and set .Va errno -for any of the errors specified for the routines -.Xr close 2 -or +for any of the errors specified for .Xr fflush 3 . +.Pp +The +.Fn fclose +function may also fail and set errno for any of the errors specified for +.Xr close 2 . .Sh NOTES The .Fn fclose -function -does not handle NULL arguments; they will result in a segmentation -violation. -This is intentional - it makes it easier to make sure programs written -under +and +.Fn fdclose +functions do not handle NULL arguments in the +.Fa stream +variable; this will result in a segmentation violation. +This is intentional. +It makes it easier to make sure programs written under .Fx are bug free. This behaviour is an implementation detail, and programs should not @@ -104,8 +149,13 @@ The function conforms to .St -isoC . -.Pp +.Sh HISTORY The .Fn fcloseall function first appeared in .Fx 7.0 . +.Pp +The +.Fn fdclose +function first appeared in +.Fx 11.0 . diff --git a/lib/libc/stdio/fclose.c b/lib/libc/stdio/fclose.c index 3957b6a42..327b2960d 100644 --- a/lib/libc/stdio/fclose.c +++ b/lib/libc/stdio/fclose.c @@ -1,6 +1,7 @@ /*- - * Copyright (c) 1990, 1993 - * The Regents of the University of California. All rights reserved. + * Copyright (c) 1990, 1993 The Regents of the University of California. + * Copyright (c) 2013 Mariusz Zaborski + * All rights reserved. * * This code is derived from software contributed to Berkeley by * Chris Torek. @@ -38,6 +39,7 @@ __FBSDID("$FreeBSD$"); #include "namespace.h" #include +#include #include #include #include "un-namespace.h" @@ -45,19 +47,17 @@ __FBSDID("$FreeBSD$"); #include "libc_private.h" #include "local.h" -int -fclose(FILE *fp) +static int +cleanfile(FILE *fp, bool c) { int r; - if (fp->_flags == 0) { /* not open! */ - errno = EBADF; - return (EOF); - } - FLOCKFILE(fp); r = fp->_flags & __SWR ? __sflush(fp) : 0; - if (fp->_close != NULL && (*fp->_close)(fp->_cookie) < 0) - r = EOF; + if (c) { + if (fp->_close != NULL && (*fp->_close)(fp->_cookie) < 0) + r = EOF; + } + if (fp->_flags & __SMBF) free((char *)fp->_bf._base); if (HASUB(fp)) @@ -80,6 +80,59 @@ fclose(FILE *fp) STDIO_THREAD_LOCK(); fp->_flags = 0; /* Release this FILE for reuse. */ STDIO_THREAD_UNLOCK(); + + return (r); +} + +int +fdclose(FILE *fp, int *fdp) +{ + int r, err; + + if (fdp != NULL) + *fdp = -1; + + if (fp->_flags == 0) { /* not open! */ + errno = EBADF; + return (EOF); + } + + FLOCKFILE(fp); + r = 0; + if (fp->_close != __sclose) { + r = EOF; + errno = EOPNOTSUPP; + } else if (fp->_file < 0) { + r = EOF; + errno = EBADF; + } + if (r == EOF) { + err = errno; + (void)cleanfile(fp, true); + errno = err; + } else { + if (fdp != NULL) + *fdp = fp->_file; + r = cleanfile(fp, false); + } FUNLOCKFILE(fp); + + return (r); +} + +int +fclose(FILE *fp) +{ + int r; + + if (fp->_flags == 0) { /* not open! */ + errno = EBADF; + return (EOF); + } + + FLOCKFILE(fp); + r = cleanfile(fp, true); + FUNLOCKFILE(fp); + return (r); } -- 2.45.0