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[209.132.180.131]) by mx.google.com with ESMTPS id o10si1536340pap.31.2015.06.16.06.56.14 for (version=TLSv1.2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Tue, 16 Jun 2015 06:56:15 -0700 (PDT) Received-SPF: pass (google.com: domain of libc-alpha-return-60067-patch=linaro.org@sourceware.org designates 209.132.180.131 as permitted sender) client-ip=209.132.180.131; Received: (qmail 44578 invoked by alias); 16 Jun 2015 13:56:04 -0000 Mailing-List: list patchwork-forward@linaro.org; contact patchwork-forward+owners@linaro.org Precedence: list List-Id: List-Unsubscribe: , List-Subscribe: List-Archive: List-Post: , List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 44567 invoked by uid 89); 16 Jun 2015 13:56:03 -0000 X-Virus-Found: No X-Spam-SWARE-Status: No, score=0.1 required=5.0 tests=AWL, BAYES_50, RCVD_IN_DNSWL_LOW, SPF_PASS, UNSUBSCRIBE_BODY autolearn=no version=3.3.2 X-HELO: mail-yk0-f181.google.com X-Received: by 10.129.86.139 with SMTP id k133mr575552ywb.53.1434462956898; Tue, 16 Jun 2015 06:55:56 -0700 (PDT) Message-ID: <55802AE9.2080602@linaro.org> Date: Tue, 16 Jun 2015 10:55:53 -0300 From: Adhemerval Zanella User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.7.0 MIME-Version: 1.0 To: GNU C Library Subject: [PATCH 1/2] libio: fmemopen rewrite to POSIX compliance X-Original-Sender: adhemerval.zanella@linaro.org X-Original-Authentication-Results: mx.google.com; spf=pass (google.com: domain of patch+caf_=patchwork-forward=linaro.org@linaro.org designates 2a00:1450:4010:c03::22e as permitted sender) smtp.mail=patch+caf_=patchwork-forward=linaro.org@linaro.org; dkim=pass header.i=@sourceware.org X-Google-Group-Id: 836684582541 Reposting this again with a clarification about bz#11216 and also to see if I can land it for 2.22. --- This patch added a new fmemopen version, for glibc 2.22, that aims to be POSIX complaint. It fixes some long-stading glibc fmemopen issues, such as: * it changes the way fseek with SEEK_END works on fmemopen to seek relative to buffer size instead of first '\0'. This is default mode and 'b' opening mode does not change internal behavior (bz#6544). * fix apending opening mode to use as start position either first null byte of len specified in function call (bz#13152 and #13151). * remove binary option 'b' and internal different handling (bz#12836) * fix seek/SEE_END with negative values (bz#14292). It does not change bz#11216 behavior for zero length buffer, however due POSIX clarification states an implementation may fail for such scenario. A compatibility symbol is provided to with old behavior for older symbols version (2.2.5). Tested on x86_64, i386, aarch64, and arm-linux-gnueabihf. * include/stdio.h (fmemopen): Remove hidden prototype. (__fmemopen): Add new hidden prototype. * libio/Makefile: Add oldfmemopen object. * libio/Versions [GLIBC_2.22]: Add new fmemopen symbol. * libio/fmemopen.c (__fmemopen): Function rewrite to be POSIX compliance. * libio/oldfmemopen.c: New file: old fmemopen implementation for symbol compatibility. * stdio-common/Makefile [tests]: Add new tst-fmemopen3. * stdio-common/psiginfo.c [psiginfo]: Call __fmemopen instead of fmemopen. * stdio-common/tst-fmemopen3.c: New file: more fmemopen tests, focus on append and read mode. * sysdeps/unix/sysv/linux/aarch64/libc.abilist [GLIBC_2.22]: Add fmemopen. * sysdeps/unix/sysv/linux/alpha/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/arm/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/i386/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/ia64/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/m68k/coldfire/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/m68k/m680x0/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/microblaze/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/fpu/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/mips/mips32/nofpu/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n32/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/mips/mips64/n64/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/powerpc/powerpc64/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/s390/s390-32/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/s390/s390-64/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/sh/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc32/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/sparc/sparc64/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/tile/tilegx/tilegx32/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/tile/tilegx/tilegx64/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/tile/tilepro/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/x86_64/64/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/x86_64/x32/libc.abilist [GLIBC_2.22]: Likewise. * sysdeps/unix/sysv/linux/hppa/libc.abilist [GLIBC_2.22]: Likewise. -- diff --git a/NEWS b/NEWS index 33cba7b..ab380c2 100644 --- a/NEWS +++ b/NEWS @@ -9,19 +9,20 @@ Version 2.22 * The following bugs are resolved with this release: - 438, 4719, 6792, 13028, 13064, 14094, 14841, 14906, 14958, 15319, 15467, - 15790, 15969, 16159, 16339, 16351, 16352, 16512, 16560, 16704, 16783, - 16850, 17053, 17090, 17195, 17269, 17293, 17322, 17523, 17542, 17569, - 17581, 17588, 17596, 17620, 17621, 17628, 17631, 17692, 17711, 17715, - 17776, 17779, 17792, 17836, 17912, 17916, 17930, 17932, 17944, 17949, - 17964, 17965, 17967, 17969, 17978, 17987, 17991, 17996, 17998, 17999, - 18007, 18019, 18020, 18029, 18030, 18032, 18036, 18038, 18039, 18042, - 18043, 18046, 18047, 18049, 18068, 18080, 18093, 18100, 18104, 18110, - 18111, 18116, 18125, 18128, 18138, 18185, 18196, 18197, 18206, 18210, - 18211, 18217, 18220, 18221, 18234, 18244, 18247, 18287, 18319, 18324, - 18333, 18346, 18397, 18409, 18410, 18412, 18418, 18422, 18434, 18444, - 18468, 18469, 18470, 18479, 18483, 18495, 18496, 18497, 18498, 18507, - 18512, 18519, 18520, 18522, 18527, 18528, 18529, 18530. + 438, 4719, 6544, 6792, 11216, 12836, 13028, 13064, 13151, 13152, + 14094, 14292, 14841, 14906, 14958, 15319, 15467, 15790, 15969, 16159, + 16339, 16351, 16352, 16512, 16560, 16704, 16783, 16850, 17053, 17090, + 17195, 17269, 17293, 17322, 17523, 17542, 17569, 17581, 17588, 17596, + 17620, 17621, 17628, 17631, 17692, 17711, 17715, 17776, 17779, 17792, + 17836, 17912, 17916, 17930, 17932, 17944, 17949, 17964, 17965, 17967, + 17969, 17978, 17987, 17991, 17996, 17998, 17999, 18007, 18019, 18020, + 18029, 18030, 18032, 18036, 18038, 18039, 18042, 18043, 18046, 18047, + 18049, 18068, 18080, 18093, 18100, 18104, 18110, 18111, 18116, 18125, + 18128, 18138, 18185, 18196, 18197, 18206, 18210, 18211, 18217, 18220, + 18221, 18234, 18244, 18247, 18287, 18319, 18324, 18333, 18346, 18397, + 18409, 18410, 18412, 18418, 18422, 18434, 18444, 18468, 18469, 18470, + 18479, 18483, 18495, 18496, 18497, 18498, 18507, 18512, 18519, 18520, + 18522, 18527, 18528, 18529, 18530. * Cache information can be queried via sysconf() function on s390 e.g. with _SC_LEVEL1_ICACHE_SIZE as argument. diff --git a/include/stdio.h b/include/stdio.h index 6ae70a3..d235aa8 100644 --- a/include/stdio.h +++ b/include/stdio.h @@ -192,6 +192,9 @@ gets (char *__str) } # endif +extern FILE * __fmemopen (void *buf, size_t len, const char *mode); +libc_hidden_proto (__fmemopen) + __END_DECLS # endif diff --git a/libio/Makefile b/libio/Makefile index 097cfae..7b3bcf9 100644 --- a/libio/Makefile +++ b/libio/Makefile @@ -46,7 +46,7 @@ routines := \ __fbufsize __freading __fwriting __freadable __fwritable __flbf \ __fpurge __fpending __fsetlocking \ \ - libc_fatal fmemopen + libc_fatal fmemopen oldfmemopen tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc \ tst_wprintf2 tst-widetext test-fmemopen tst-ext tst-ext2 \ diff --git a/libio/Versions b/libio/Versions index 8df89d2..2a1d6e6 100644 --- a/libio/Versions +++ b/libio/Versions @@ -148,6 +148,10 @@ libc { GLIBC_2.4 { open_wmemstream; } + GLIBC_2.22 { + # f* + fmemopen; + } GLIBC_PRIVATE { # Used by NPTL and librt __libc_fatal; diff --git a/libio/fmemopen.c b/libio/fmemopen.c index 6c50fba..1f0d661 100644 --- a/libio/fmemopen.c +++ b/libio/fmemopen.c @@ -1,7 +1,6 @@ -/* Fmemopen implementation. - Copyright (C) 2000-2015 Free Software Foundation, Inc. +/* fmemopen implementation. + Copyright (C) 2015 Free Software Foundation, Inc. This file is part of the GNU C Library. - Contributed by Hanno Mueller, kontakt@hanno.de, 2000. The GNU C Library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public @@ -17,54 +16,10 @@ License along with the GNU C Library; if not, see . */ -/* - * fmemopen() - "my" version of a string stream - * Hanno Mueller, kontakt@hanno.de - * - * - * I needed fmemopen() for an application that I currently work on, - * but couldn't find it in libio. The following snippet of code is an - * attempt to implement what glibc's documentation describes. - * - * - * - * I already see some potential problems: - * - * - I never used the "original" fmemopen(). I am sure that "my" - * fmemopen() behaves differently than the original version. - * - * - The documentation doesn't say wether a string stream allows - * seeks. I checked the old fmemopen implementation in glibc's stdio - * directory, wasn't quite able to see what is going on in that - * source, but as far as I understand there was no seek there. For - * my application, I needed fseek() and ftell(), so it's here. - * - * - "append" mode and fseek(p, SEEK_END) have two different ideas - * about the "end" of the stream. - * - * As described in the documentation, when opening the file in - * "append" mode, the position pointer will be set to the first null - * character of the string buffer (yet the buffer may already - * contain more data). For fseek(), the last byte of the buffer is - * used as the end of the stream. - * - * - It is unclear to me what the documentation tries to say when it - * explains what happens when you use fmemopen with a NULL - * buffer. - * - * Quote: "fmemopen [then] allocates an array SIZE bytes long. This - * is really only useful if you are going to write things to the - * buffer and then read them back in again." - * - * What does that mean if the original fmemopen() did not allow - * seeking? How do you read what you just wrote without seeking back - * to the beginning of the stream? - * - * - I think there should be a second version of fmemopen() that does - * not add null characters for each write. (At least in my - * application, I am not actually using strings but binary data and - * so I don't need the stream to add null characters on its own.) - */ +/* fmemopen() from 2.22 and forward works as defined by POSIX. It also + provides an older symbol, version 2.2.5, that behaves different regarding + SEEK_END (libio/oldfmemopen.c). */ + #include #include @@ -79,25 +34,23 @@ typedef struct fmemopen_cookie_struct fmemopen_cookie_t; struct fmemopen_cookie_struct { - char *buffer; - int mybuffer; - int binmode; - size_t size; - _IO_off64_t pos; - size_t maxpos; + char *buffer; /* memory buffer. */ + int mybuffer; /* own allocated buffer? */ + int append; /* buffer openened for append? */ + size_t size; /* buffer length in bytes. */ + _IO_off64_t pos; /* current position at the buffer. */ + size_t maxpos; /* max position in buffer. */ }; static ssize_t fmemopen_read (void *cookie, char *b, size_t s) { - fmemopen_cookie_t *c; - - c = (fmemopen_cookie_t *) cookie; + fmemopen_cookie_t *c = (fmemopen_cookie_t *) cookie; - if (c->pos + s > c->size) + if (c->pos + s > c->maxpos) { - if ((size_t) c->pos == c->size) + if ((size_t) c->pos == c->maxpos) return 0; s = c->size - c->pos; } @@ -115,29 +68,28 @@ fmemopen_read (void *cookie, char *b, size_t s) static ssize_t fmemopen_write (void *cookie, const char *b, size_t s) { - fmemopen_cookie_t *c; + fmemopen_cookie_t *c = (fmemopen_cookie_t *) cookie;; + _IO_off64_t pos = c->append ? c->maxpos : c->pos; int addnullc; - c = (fmemopen_cookie_t *) cookie; - - addnullc = c->binmode == 0 && (s == 0 || b[s - 1] != '\0'); + addnullc = (s == 0 || b[s - 1] != '\0'); - if (c->pos + s + addnullc > c->size) + if (pos + s + addnullc > c->size) { - if ((size_t) (c->pos + addnullc) == c->size) + if ((size_t) (pos + addnullc) >= c->size) { __set_errno (ENOSPC); return 0; } - s = c->size - c->pos - addnullc; + s = c->size - pos - addnullc; } - memcpy (&(c->buffer[c->pos]), b, s); + memcpy (&(c->buffer[pos]), b, s); - c->pos += s; - if ((size_t) c->pos > c->maxpos) + pos += s; + if ((size_t) pos > c->maxpos) { - c->maxpos = c->pos; + c->maxpos = pos; if (addnullc) c->buffer[c->maxpos] = '\0'; } @@ -150,9 +102,7 @@ static int fmemopen_seek (void *cookie, _IO_off64_t *p, int w) { _IO_off64_t np; - fmemopen_cookie_t *c; - - c = (fmemopen_cookie_t *) cookie; + fmemopen_cookie_t *c = (fmemopen_cookie_t *) cookie; switch (w) { @@ -165,7 +115,7 @@ fmemopen_seek (void *cookie, _IO_off64_t *p, int w) break; case SEEK_END: - np = (c->binmode ? c->size : c->maxpos) - *p; + np = c->maxpos + *p; break; default: @@ -184,9 +134,7 @@ fmemopen_seek (void *cookie, _IO_off64_t *p, int w) static int fmemopen_close (void *cookie) { - fmemopen_cookie_t *c; - - c = (fmemopen_cookie_t *) cookie; + fmemopen_cookie_t *c = (fmemopen_cookie_t *) cookie; if (c->mybuffer) free (c->buffer); @@ -197,18 +145,11 @@ fmemopen_close (void *cookie) FILE * -fmemopen (void *buf, size_t len, const char *mode) +__fmemopen (void *buf, size_t len, const char *mode) { cookie_io_functions_t iof; fmemopen_cookie_t *c; - if (__glibc_unlikely (len == 0)) - { - einval: - __set_errno (EINVAL); - return NULL; - } - c = (fmemopen_cookie_t *) malloc (sizeof (fmemopen_cookie_t)); if (c == NULL) return NULL; @@ -231,26 +172,38 @@ fmemopen (void *buf, size_t len, const char *mode) if (__glibc_unlikely ((uintptr_t) len > -(uintptr_t) buf)) { free (c); - goto einval; + __set_errno (EINVAL); + return NULL; } c->buffer = buf; - if (mode[0] == 'w') + /* POSIX states that w+ mode should truncate the buffer. */ + if (mode[0] == 'w' && mode[1] == '+') c->buffer[0] = '\0'; c->maxpos = strnlen (c->buffer, len); } + + /* Mode | starting position (cookie::pos) | size (cookie::size) + * ------ |----------------------------------|----------------------------- + * read | beginning of the buffer | size argument + * write | beginning of the buffer | zero + * append | first null or size buffer + 1 | first null or size argument + */ + c->size = len; - if (mode[0] == 'a') + if (mode[0] == 'r') + c->maxpos = len; + + c->append = mode[0] == 'a'; + if (c->append) c->pos = c->maxpos; else c->pos = 0; - c->binmode = mode[0] != '\0' && mode[1] == 'b'; - iof.read = fmemopen_read; iof.write = fmemopen_write; iof.seek = fmemopen_seek; @@ -258,4 +211,5 @@ fmemopen (void *buf, size_t len, const char *mode) return _IO_fopencookie (c, mode, iof); } -libc_hidden_def (fmemopen) +libc_hidden_def (__fmemopen) +versioned_symbol (libc, __fmemopen, fmemopen, GLIBC_2_22); diff --git a/libio/oldfmemopen.c b/libio/oldfmemopen.c new file mode 100644 index 0000000..6e84acf --- /dev/null +++ b/libio/oldfmemopen.c @@ -0,0 +1,265 @@ +/* Fmemopen implementation. + Copyright (C) 2000-2015 Free Software Foundation, Inc. + This file is part of the GNU C Library. + Contributed by Hanno Mueller, kontakt@hanno.de, 2000. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +/* + * fmemopen() - "my" version of a string stream + * Hanno Mueller, kontakt@hanno.de + * + * + * I needed fmemopen() for an application that I currently work on, + * but couldn't find it in libio. The following snippet of code is an + * attempt to implement what glibc's documentation describes. + * + * + * + * I already see some potential problems: + * + * - I never used the "original" fmemopen(). I am sure that "my" + * fmemopen() behaves differently than the original version. + * + * - The documentation doesn't say wether a string stream allows + * seeks. I checked the old fmemopen implementation in glibc's stdio + * directory, wasn't quite able to see what is going on in that + * source, but as far as I understand there was no seek there. For + * my application, I needed fseek() and ftell(), so it's here. + * + * - "append" mode and fseek(p, SEEK_END) have two different ideas + * about the "end" of the stream. + * + * As described in the documentation, when opening the file in + * "append" mode, the position pointer will be set to the first null + * character of the string buffer (yet the buffer may already + * contain more data). For fseek(), the last byte of the buffer is + * used as the end of the stream. + * + * - It is unclear to me what the documentation tries to say when it + * explains what happens when you use fmemopen with a NULL + * buffer. + * + * Quote: "fmemopen [then] allocates an array SIZE bytes long. This + * is really only useful if you are going to write things to the + * buffer and then read them back in again." + * + * What does that mean if the original fmemopen() did not allow + * seeking? How do you read what you just wrote without seeking back + * to the beginning of the stream? + * + * - I think there should be a second version of fmemopen() that does + * not add null characters for each write. (At least in my + * application, I am not actually using strings but binary data and + * so I don't need the stream to add null characters on its own.) + */ + +#include "libioP.h" + +#if SHLIB_COMPAT (libc, GLIBC_2_2, GLIBC_2_22) + +#include +#include +#include +#include +#include +#include +#include + + +typedef struct fmemopen_cookie_struct fmemopen_cookie_t; +struct fmemopen_cookie_struct +{ + char *buffer; + int mybuffer; + int binmode; + size_t size; + _IO_off64_t pos; + size_t maxpos; +}; + + +static ssize_t +fmemopen_read (void *cookie, char *b, size_t s) +{ + fmemopen_cookie_t *c; + + c = (fmemopen_cookie_t *) cookie; + + if (c->pos + s > c->size) + { + if ((size_t) c->pos == c->size) + return 0; + s = c->size - c->pos; + } + + memcpy (b, &(c->buffer[c->pos]), s); + + c->pos += s; + if ((size_t) c->pos > c->maxpos) + c->maxpos = c->pos; + + return s; +} + + +static ssize_t +fmemopen_write (void *cookie, const char *b, size_t s) +{ + fmemopen_cookie_t *c; + int addnullc; + + c = (fmemopen_cookie_t *) cookie; + + addnullc = c->binmode == 0 && (s == 0 || b[s - 1] != '\0'); + + if (c->pos + s + addnullc > c->size) + { + if ((size_t) (c->pos + addnullc) == c->size) + { + __set_errno (ENOSPC); + return 0; + } + s = c->size - c->pos - addnullc; + } + + memcpy (&(c->buffer[c->pos]), b, s); + + c->pos += s; + if ((size_t) c->pos > c->maxpos) + { + c->maxpos = c->pos; + if (addnullc) + c->buffer[c->maxpos] = '\0'; + } + + return s; +} + + +static int +fmemopen_seek (void *cookie, _IO_off64_t *p, int w) +{ + _IO_off64_t np; + fmemopen_cookie_t *c; + + c = (fmemopen_cookie_t *) cookie; + + switch (w) + { + case SEEK_SET: + np = *p; + break; + + case SEEK_CUR: + np = c->pos + *p; + break; + + case SEEK_END: + np = (c->binmode ? c->size : c->maxpos) - *p; + break; + + default: + return -1; + } + + if (np < 0 || (size_t) np > c->size) + return -1; + + *p = c->pos = np; + + return 0; +} + + +static int +fmemopen_close (void *cookie) +{ + fmemopen_cookie_t *c; + + c = (fmemopen_cookie_t *) cookie; + + if (c->mybuffer) + free (c->buffer); + free (c); + + return 0; +} + + +FILE * +__old_fmemopen (void *buf, size_t len, const char *mode) +{ + cookie_io_functions_t iof; + fmemopen_cookie_t *c; + + if (__glibc_unlikely (len == 0)) + { + einval: + __set_errno (EINVAL); + return NULL; + } + + c = (fmemopen_cookie_t *) malloc (sizeof (fmemopen_cookie_t)); + if (c == NULL) + return NULL; + + c->mybuffer = (buf == NULL); + + if (c->mybuffer) + { + c->buffer = (char *) malloc (len); + if (c->buffer == NULL) + { + free (c); + return NULL; + } + c->buffer[0] = '\0'; + c->maxpos = 0; + } + else + { + if (__glibc_unlikely ((uintptr_t) len > -(uintptr_t) buf)) + { + free (c); + goto einval; + } + + c->buffer = buf; + + if (mode[0] == 'w') + c->buffer[0] = '\0'; + + c->maxpos = strnlen (c->buffer, len); + } + + c->size = len; + + if (mode[0] == 'a') + c->pos = c->maxpos; + else + c->pos = 0; + + c->binmode = mode[0] != '\0' && mode[1] == 'b'; + + iof.read = fmemopen_read; + iof.write = fmemopen_write; + iof.seek = fmemopen_seek; + iof.close = fmemopen_close; + + return _IO_fopencookie (c, mode, iof); +} +compat_symbol (libc, __old_fmemopen, fmemopen, GLIBC_2_2); +#endif diff --git a/stdio-common/Makefile b/stdio-common/Makefile index 8567056..d0bf0e1 100644 --- a/stdio-common/Makefile +++ b/stdio-common/Makefile @@ -57,7 +57,7 @@ tests := tstscanf test_rdwr test-popen tstgetln test-fseek \ bug19 bug19a tst-popen2 scanf13 scanf14 scanf15 bug20 bug21 bug22 \ scanf16 scanf17 tst-setvbuf1 tst-grouping bug23 bug24 \ bug-vfprintf-nargs tst-long-dbl-fphex tst-fphex-wide tst-sprintf3 \ - bug25 tst-printf-round bug23-2 bug23-3 bug23-4 bug26 + bug25 tst-printf-round bug23-2 bug23-3 bug23-4 bug26 tst-fmemopen3 test-srcs = tst-unbputc tst-printf diff --git a/stdio-common/psiginfo.c b/stdio-common/psiginfo.c index 3aff501..30847ea 100644 --- a/stdio-common/psiginfo.c +++ b/stdio-common/psiginfo.c @@ -60,7 +60,7 @@ void psiginfo (const siginfo_t *pinfo, const char *s) { char buf[512]; - FILE *fp = fmemopen (buf, sizeof (buf), "w"); + FILE *fp = __fmemopen (buf, sizeof (buf), "w"); if (fp == NULL) { const char *colon; diff --git a/stdio-common/tst-fmemopen3.c b/stdio-common/tst-fmemopen3.c new file mode 100644 index 0000000..be48153 --- /dev/null +++ b/stdio-common/tst-fmemopen3.c @@ -0,0 +1,206 @@ +/* fmemopen tests for append and read mode. + Copyright (C) 2015 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include + +static void +print_buffer (const char *s, size_t n) +{ + size_t i; + for (i=0; i