Author: cem Date: Wed May 11 14:38:27 2016 New Revision: 299456 URL: https://svnweb.freebsd.org/changeset/base/299456
Log: libc: Add fopencookie(3) wrapper around funopen(3) Reviewed by: jhb, oshogbo Sponsored by: EMC / Isilon Storage Division Differential Revision: https://reviews.freebsd.org/D6282 Added: head/lib/libc/stdio/fopencookie.3 (contents, props changed) head/lib/libc/stdio/fopencookie.c (contents, props changed) Modified: head/include/stdio.h head/lib/libc/stdio/Makefile.inc head/lib/libc/stdio/funopen.3 Modified: head/include/stdio.h ============================================================================== --- head/include/stdio.h Wed May 11 14:37:33 2016 (r299455) +++ head/include/stdio.h Wed May 11 14:38:27 2016 (r299456) @@ -58,6 +58,11 @@ typedef __ssize_t ssize_t; #endif #endif +#ifndef _OFF64_T_DECLARED +#define _OFF64_T_DECLARED +typedef __off_t off64_t; +#endif + #if __POSIX_VISIBLE >= 200112 || __XSI_VISIBLE #ifndef _VA_LIST_DECLARED typedef __va_list va_list; @@ -427,6 +432,18 @@ FILE *funopen(const void *, #define fropen(cookie, fn) funopen(cookie, fn, 0, 0, 0) #define fwopen(cookie, fn) funopen(cookie, 0, fn, 0, 0) +typedef ssize_t (cookie_read_function_t)(void *, char *, size_t); +typedef ssize_t (cookie_write_function_t)(void *, const char *, size_t); +typedef int (cookie_seek_function_t)(void *, off64_t *, int); +typedef int (cookie_close_function_t)(void *); +typedef struct { + cookie_read_function_t *read; + cookie_write_function_t *write; + cookie_seek_function_t *seek; + cookie_close_function_t *close; +} cookie_io_functions_t; +FILE *fopencookie(void *, const char *, cookie_io_functions_t); + /* * Portability hacks. See <sys/types.h>. */ Modified: head/lib/libc/stdio/Makefile.inc ============================================================================== --- head/lib/libc/stdio/Makefile.inc Wed May 11 14:37:33 2016 (r299455) +++ head/lib/libc/stdio/Makefile.inc Wed May 11 14:38:27 2016 (r299456) @@ -8,7 +8,8 @@ SRCS+= _flock_stub.c asprintf.c clrerr.c fclose.c fcloseall.c fdopen.c \ feof.c ferror.c fflush.c fgetc.c fgetln.c fgetpos.c fgets.c fgetwc.c \ fgetwln.c fgetws.c \ - fileno.c findfp.c flags.c fmemopen.c fopen.c fprintf.c fpurge.c \ + fileno.c findfp.c flags.c fmemopen.c fopen.c \ + fopencookie.c fprintf.c fpurge.c \ fputc.c fputs.c \ fputwc.c fputws.c fread.c freopen.c fscanf.c fseek.c fsetpos.c \ ftell.c funopen.c fvwrite.c fwalk.c fwide.c fwprintf.c fwscanf.c \ @@ -35,7 +36,7 @@ SYM_MAPS+= ${LIBC_SRCTOP}/stdio/Symbol.m MAN+= fclose.3 ferror.3 fflush.3 fgetln.3 fgets.3 fgetwln.3 fgetws.3 \ flockfile.3 \ - fopen.3 fputs.3 \ + fopen.3 fopencookie.3 fputs.3 \ fputws.3 fread.3 fseek.3 funopen.3 fwide.3 getc.3 \ getline.3 getwc.3 mktemp.3 open_memstream.3 \ printf.3 printf_l.3 putc.3 putwc.3 remove.3 scanf.3 scanf_l.3 setbuf.3 \ Added: head/lib/libc/stdio/fopencookie.3 ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ head/lib/libc/stdio/fopencookie.3 Wed May 11 14:38:27 2016 (r299456) @@ -0,0 +1,156 @@ +.\" Copyright (c) 2016, EMC / Isilon Storage Division +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS +.\" IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, +.\" THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR +.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR +.\" CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, +.\" EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, +.\" PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; +.\" OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, +.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR +.\" OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF +.\" ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. +.\" +.\" $FreeBSD$ +.\" +.Dd May 9, 2016 +.Dt FOPENCOOKIE 3 +.Os +.Sh NAME +.Nm fopencookie +.Nd open a stream +.Sh LIBRARY +.Lb libc +.Sh SYNOPSIS +.In stdio.h +.Ft typedef ssize_t +.Fn (cookie_read_function_t) "void *cookie" "char *buf" "size_t size" +.Ft typedef ssize_t +.Fn (cookie_write_function_t) "void *cookie" "const char *buf" "size_t size" +.Ft typedef int +.Fn (cookie_seek_function_t) "void *cookie" "off64_t *offset" "int whence" +.Ft typedef int +.Fn (cookie_close_function_t) "void *cookie" +.Bd -literal +typedef struct { + cookie_read_function_t *read; + cookie_write_function_t *write; + cookie_seek_function_t *seek; + cookie_close_function_t *close; +} cookie_io_functions_t; +.Ed +.Ft FILE * +.Fn fopencookie "void *cookie" "const char *mode" "cookie_io_functions_t io_funcs" +.Sh DESCRIPTION +The +.Nm +function +associates a stream with up to four +.Dq Tn I/O No functions . +These +.Tn I/O +functions will be used to read, write, seek and +close the new stream. +.Pp +In general, omitting a function means that any attempt to perform the +associated operation on the resulting stream will fail. +If the write function is omitted, data written to the stream is discarded. +If the close function is omitted, closing the stream will flush +any buffered output and then succeed. +.Pp +The calling conventions of +.Fa read , +.Fa write , +and +.Fa close +must match those, respectively, of +.Xr read 2 , +.Xr write 2 , +and +.Xr close 2 +with the single exception that they are passed the +.Fa cookie +argument specified to +.Nm +in place of the traditional file descriptor argument. +The +.Fa seek +function updates the current stream offset using +.Fa *offset +and +.Fa whence . +If +.Fa *offset +is non-NULL, it updates +.Fa *offset +with the current stream offset. +.Pp +.Nm +is implemented as a thin shim around the +.Xr funopen 3 +interface. +Limitations, possibilities, and requirements of that interface apply to +.Nm . +.Sh RETURN VALUES +Upon successful completion, +.Nm +returns a +.Dv FILE +pointer. +Otherwise, +.Dv NULL +is returned and the global variable +.Va errno +is set to indicate the error. +.Sh ERRORS +.Bl -tag -width Er +.It Bq Er EINVAL +A bogus +.Fa mode +was provided to +.Nm . +.It Bq Er ENOMEM +The +.Nm +function +may fail and set +.Va errno +for any of the errors +specified for the +.Xr malloc 3 +routine. +.El +.Sh SEE ALSO +.Xr fcntl 2 , +.Xr open 2 , +.Xr fclose 3 , +.Xr fopen 3 , +.Xr fseek 3 , +.Xr funopen 3 +.Sh HISTORY +The +.Fn funopen +functions first appeared in +.Bx 4.4 . +The +.Nm +function first appeared in +.Fx 11 . +.Sh BUGS +The +.Nm +function is a nonstandard glibc extension and may not be portable to systems +other than +.Fx +and Linux. Added: head/lib/libc/stdio/fopencookie.c ============================================================================== --- /dev/null 00:00:00 1970 (empty, because file is newly added) +++ head/lib/libc/stdio/fopencookie.c Wed May 11 14:38:27 2016 (r299456) @@ -0,0 +1,168 @@ +/* + * Copyright (c) 2016, EMC / Isilon Storage Division + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS + * IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, + * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, + * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, + * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; + * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, + * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR + * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include <sys/cdefs.h> +__FBSDID("$FreeBSD$"); + +#include <sys/fcntl.h> + +#include <errno.h> +#include <stdio.h> +#include <stdlib.h> + +#include "local.h" + +struct fopencookie_thunk { + void *foc_cookie; + cookie_io_functions_t foc_io; +}; + +static int _fopencookie_read(void *, char *, int); +static int _fopencookie_write(void *, const char *, int); +static fpos_t _fopencookie_seek(void *, fpos_t, int); +static int _fopencookie_close(void *); + +FILE * +fopencookie(void *cookie, const char *mode, cookie_io_functions_t io_funcs) +{ + int (*readfn)(void *, char *, int); + int (*writefn)(void *, const char *, int); + struct fopencookie_thunk *thunk; + FILE *fp; + int flags, oflags; + + if ((flags = __sflags(mode, &oflags)) == 0) + return (NULL); + + thunk = malloc(sizeof(*thunk)); + if (thunk == NULL) + return (NULL); + + thunk->foc_cookie = cookie; + thunk->foc_io = io_funcs; + + readfn = _fopencookie_read; + writefn = _fopencookie_write; + if (flags == __SWR) + readfn = NULL; + else if (flags == __SRD) + writefn = NULL; + + fp = funopen(thunk, readfn, writefn, _fopencookie_seek, + _fopencookie_close); + if (fp == NULL) { + free(thunk); + return (NULL); + } + + if ((oflags & O_APPEND) != 0) + fp->_flags |= __SAPP; + + return (fp); +} + +static int +_fopencookie_read(void *cookie, char *buf, int size) +{ + struct fopencookie_thunk *thunk; + + thunk = cookie; + + /* Reads from a stream with NULL read return EOF. */ + if (thunk->foc_io.read == NULL) + return (0); + + return ((int)thunk->foc_io.read(thunk->foc_cookie, buf, (size_t)size)); +} + +static int +_fopencookie_write(void *cookie, const char *buf, int size) +{ + struct fopencookie_thunk *thunk; + + thunk = cookie; + + /* Writes to a stream with NULL write discard data. */ + if (thunk->foc_io.write == NULL) + return (size); + + return ((int)thunk->foc_io.write(thunk->foc_cookie, buf, + (size_t)size)); +} + +static fpos_t +_fopencookie_seek(void *cookie, fpos_t offset, int whence) +{ + struct fopencookie_thunk *thunk; + off64_t off64; + int res; + + switch (whence) { + case SEEK_SET: + case SEEK_CUR: + case SEEK_END: + break; + default: + /* fopencookie(3) only allows these three seek modes. */ + errno = EINVAL; + return (-1); + } + + thunk = cookie; + + /* + * If seek is NULL, it is not possible to perform seek operations on + * the stream. + */ + if (thunk->foc_io.seek == NULL) { + errno = ENOTSUP; + return (-1); + } + + off64 = (off64_t)offset; + res = thunk->foc_io.seek(thunk->foc_cookie, &off64, whence); + if (res < 0) + return (res); + + return ((fpos_t)off64); +} + +static int +_fopencookie_close(void *cookie) +{ + struct fopencookie_thunk *thunk; + int ret, serrno; + + ret = 0; + thunk = cookie; + if (thunk->foc_io.close != NULL) + ret = thunk->foc_io.close(thunk->foc_cookie); + + serrno = errno; + free(thunk); + errno = serrno; + return (ret); +} Modified: head/lib/libc/stdio/funopen.3 ============================================================================== --- head/lib/libc/stdio/funopen.3 Wed May 11 14:37:33 2016 (r299455) +++ head/lib/libc/stdio/funopen.3 Wed May 11 14:38:27 2016 (r299456) @@ -30,7 +30,7 @@ .\" @(#)funopen.3 8.1 (Berkeley) 6/9/93 .\" $FreeBSD$ .\" -.Dd March 19, 2004 +.Dd May 9, 2016 .Dt FUNOPEN 3 .Os .Sh NAME @@ -153,6 +153,7 @@ specified for the routine .Xr open 2 , .Xr fclose 3 , .Xr fopen 3 , +.Xr fopencookie 3 , .Xr fseek 3 , .Xr setbuf 3 .Sh HISTORY _______________________________________________ svn-src-all@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"
