From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 95095 invoked by alias); 30 Sep 2016 00:06:47 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Received: (qmail 95069 invoked by uid 89); 30 Sep 2016 00:06:46 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-1.9 required=5.0 tests=AWL,BAYES_00,RCVD_IN_DNSWL_NONE,SPF_PASS autolearn=ham version=3.3.2 spammy=1128, CHAR_T, char_t, H*M:6682 X-HELO: mail-pf0-f182.google.com X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:subject:to:references:from:message-id:date :user-agent:mime-version:in-reply-to:content-transfer-encoding; bh=e64rDalpr/E3oWEmbNVcqYyJMNenSco5xNfjQfyDxTQ=; b=Wul3yTWs72yc5Ogw7sj0af5Y9cutwJtXmgbN0biZEKw1DmGsLkV7/+70bGDUzsVbti 1fwQf6AGgtaknBEBaYjXFgAKyYJtNmGkpbBQPzVPxwsq9tDVUF3iHdBPPWnY3qgRQVYJ k5pHMw0b8p/nBuuPpIBjSeXkVn9R2CYQCX1GHX+arooX8E5EIlg9yk2utt4A5r479dS2 BK0Rp+tRwq20Q+E4/xYBbJrnjlTB0eH5Rjh4FTo0fdv1D9O629fO0c9JJsYSeVmnUCgi HROPcQ8jUIgOq2xu91RNpCBgnX+lrFFtVuR75iwJC/ZP4Tm3WaTZ+Pk3EHm50a7RkG7x b9eg== X-Gm-Message-State: AA6/9Rkpx9qtpD4AJm9DWQAU6JiRdAZSUkgXVNPV+sNxoOLG0Ncn07dqCQP7vDt4f487PwUP X-Received: by 10.98.223.218 with SMTP id d87mr7108861pfl.48.1475193993848; Thu, 29 Sep 2016 17:06:33 -0700 (PDT) Subject: Re: [PATCH v2 1/2] libio: Multiple fixes for open_{w}memstram (BZ#18241 and BZ#20181) To: libc-alpha@sourceware.org References: <1470418850-22175-1-git-send-email-adhemerval.zanella@linaro.org> <1470688986-8798-1-git-send-email-adhemerval.zanella@linaro.org> <5c79672d-83e2-2869-190b-4de195d0252d@linaro.org> From: Adhemerval Zanella Message-ID: <45f62b93-6682-ea3d-fc47-39d10738eddd@linaro.org> Date: Fri, 30 Sep 2016 00:06:00 -0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.3.0 MIME-Version: 1.0 In-Reply-To: <5c79672d-83e2-2869-190b-4de195d0252d@linaro.org> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit X-SW-Source: 2016-09/txt/msg00598.txt.bz2 Ping. On 25/08/2016 12:53, Adhemerval Zanella wrote: > Ping. > > On 08/08/2016 17:43, Adhemerval Zanella wrote: >> Changes from previous version: >> >> * Set EINVAL on _IO_{w}str_seekoff and remove INVALPOS >> * Rewrite how to print error messages in tests to avoid put __FILE__ in >> format string. >> * Indentation and style fixes. >> >> -- >> >> This patches fixes multiples issues on open_{w}memstream reported on both >> BZ#18241 and BZ#20181: >> >> - failed fseek does not set errno. >> - negative offset in fseek fails even when resulting position is >> a valid one. >> - a flush after write if the current write position is not at the >> end of the stream currupt data. >> >> The main fix is on seek operation for memstream (_IO_{w}str_seekoff), where >> both _IO_read_ptr and _IO_read_end pointer are updated if a write operation >> has occured (similar to default file operations). Also, to calculate the >> offset on both read and write pointers, a temporary value is instead of >> updating the argument supplied value. Negative offset are valid if resulting >> internal pointer is within the range of _IO_{read,write}_base and >> _IO_{read,write}_end. >> >> Also POSIX states that a null or wide null shall be appended to the current >> buffer iff a write moves the position to a value larger than the current >> lenght. Current implementation appends a null or wide null regardless >> of this condition. This patch fixes it by removing the 'else' condition >> on _IO_{w}mem_sync. >> >> Checked on x86_64. >> >> [BZ #18241] >> [BZ #20181] >> * libio/Makefile (test): Add tst-memstream3 and tst-wmemstream3. >> * libio/memstream.c (_IO_mem_sync): Only append a null byte if >> write position is at the end the buffer. >> * libio/wmemstream.c (_IO_wmem_sync): Likewise. >> * libio/strops.c (_IO_str_switch_to_get_mode): New function. >> (_IO_str_seekoff): Set correct offset from negative displacement and >> set EINVAL for invalid ones. >> * libio/wstrops.c (enlarge_userbuf): Use correct function to calculate >> buffer length. >> (_IO_wstr_switch_to_get_mode): New function. >> (_IO_wstr_seekoff): Set correct offset from negative displacement and >> set EINVAL for invalid ones. >> * libio/tst-memstream3.c: New file. >> * libio/tst-wmemstream3.c: Likewise. >> * manual/examples/memstrm.c: Remove warning when priting size_t. >> --- >> ChangeLog | 20 ++++++ >> libio/Makefile | 4 +- >> libio/memstream.c | 2 - >> libio/strops.c | 81 +++++++++++++++-------- >> libio/tst-memstream3.c | 165 ++++++++++++++++++++++++++++++++++++++++++++++ >> libio/tst-wmemstream3.c | 44 +++++++++++++ >> libio/wmemstream.c | 2 - >> libio/wstrops.c | 89 +++++++++++++++++-------- >> manual/examples/memstrm.c | 4 +- >> 9 files changed, 348 insertions(+), 63 deletions(-) >> create mode 100644 libio/tst-memstream3.c >> create mode 100644 libio/tst-wmemstream3.c >> >> diff --git a/ChangeLog b/ChangeLog >> index 205da06..28d9012 100644 >> --- a/ChangeLog >> +++ b/ChangeLog >> @@ -1,3 +1,23 @@ >> +2016-08-05 Adhemerval Zanella >> + >> + [BZ #18241] >> + [BZ #20181] >> + * libio/Makefile (test): Add tst-memstream3 and tst-wmemstream3. >> + * libio/memstream.c (_IO_mem_sync): Only append a null byte if >> + write position is at the end the buffer. >> + * libio/wmemstream.c (_IO_wmem_sync): Likewise. >> + * libio/strops.c (_IO_str_switch_to_get_mode): New function. >> + (_IO_str_seekoff): Set correct offset from negative displacement and >> + set EINVAL for invalid ones. >> + * libio/wstrops.c (enlarge_userbuf): Use correct function to calculate >> + buffer length. >> + (_IO_wstr_switch_to_get_mode): New function. >> + (_IO_wstr_seekoff): Set correct offset from negative displacement and >> + set EINVAL for invalid ones. >> + * libio/tst-memstream3.c: New file. >> + * libio/tst-wmemstream3.c: Likewise. >> + * manual/examples/memstrm.c: Remove warning when priting size_t. >> + >> 2016-08-05 Torvald Riegel >> >> * include/atomic.h (atomic_exchange_relaxed): New. >> diff --git a/libio/Makefile b/libio/Makefile >> index 12589f2..0c7751c 100644 >> --- a/libio/Makefile >> +++ b/libio/Makefile >> @@ -56,8 +56,8 @@ tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc \ >> tst-mmap-eofsync tst-mmap-fflushsync bug-mmap-fflush \ >> tst-mmap2-eofsync tst-mmap-offend bug-fopena+ bug-wfflush \ >> bug-ungetc2 bug-ftell bug-ungetc3 bug-ungetc4 tst-fopenloc2 \ >> - tst-memstream1 tst-memstream2 \ >> - tst-wmemstream1 tst-wmemstream2 \ >> + tst-memstream1 tst-memstream2 tst-memstream3 \ >> + tst-wmemstream1 tst-wmemstream2 tst-wmemstream3 \ >> bug-memstream1 bug-wmemstream1 \ >> tst-setvbuf1 tst-popen1 tst-fgetwc bug-wsetpos tst-fseek \ >> tst-fwrite-error tst-ftell-partial-wide tst-ftell-active-handler \ >> diff --git a/libio/memstream.c b/libio/memstream.c >> index e20b9c2..f1e8d58 100644 >> --- a/libio/memstream.c >> +++ b/libio/memstream.c >> @@ -112,8 +112,6 @@ _IO_mem_sync (_IO_FILE *fp) >> _IO_str_overflow (fp, '\0'); >> --fp->_IO_write_ptr; >> } >> - else >> - *fp->_IO_write_ptr = '\0'; >> >> *mp->bufloc = fp->_IO_write_base; >> *mp->sizeloc = fp->_IO_write_ptr - fp->_IO_write_base; >> diff --git a/libio/strops.c b/libio/strops.c >> index 2ba3704..1bb8a77 100644 >> --- a/libio/strops.c >> +++ b/libio/strops.c >> @@ -230,6 +230,21 @@ enlarge_userbuf (_IO_FILE *fp, _IO_off64_t offset, int reading) >> return 0; >> } >> >> +static void >> +_IO_str_switch_to_get_mode (_IO_FILE *fp) >> +{ >> + if (_IO_in_backup (fp)) >> + fp->_IO_read_base = fp->_IO_backup_base; >> + else >> + { >> + fp->_IO_read_base = fp->_IO_buf_base; >> + if (fp->_IO_write_ptr > fp->_IO_read_end) >> + fp->_IO_read_end = fp->_IO_write_ptr; >> + } >> + fp->_IO_read_ptr = fp->_IO_read_end = fp->_IO_write_ptr; >> + >> + fp->_flags &= ~_IO_CURRENTLY_PUTTING; >> +} >> >> _IO_off64_t >> _IO_str_seekoff (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) >> @@ -239,14 +254,14 @@ _IO_str_seekoff (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) >> if (mode == 0 && (fp->_flags & _IO_TIED_PUT_GET)) >> mode = (fp->_flags & _IO_CURRENTLY_PUTTING ? _IOS_OUTPUT : _IOS_INPUT); >> >> + bool was_writing = (fp->_IO_write_ptr > fp->_IO_write_base >> + || _IO_in_put_mode (fp)); >> + if (was_writing) >> + _IO_str_switch_to_get_mode (fp); >> + >> if (mode == 0) >> { >> - /* Don't move any pointers. But there is no clear indication what >> - mode FP is in. Let's guess. */ >> - if (fp->_IO_file_flags & _IO_NO_WRITES) >> - new_pos = fp->_IO_read_ptr - fp->_IO_read_base; >> - else >> - new_pos = fp->_IO_write_ptr - fp->_IO_write_base; >> + new_pos = fp->_IO_read_ptr - fp->_IO_read_base; >> } >> else >> { >> @@ -256,48 +271,62 @@ _IO_str_seekoff (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) >> /* Move the get pointer, if requested. */ >> if (mode & _IOS_INPUT) >> { >> + _IO_ssize_t base; >> switch (dir) >> { >> - case _IO_seek_end: >> - offset += cur_size; >> + case _IO_seek_set: >> + base = 0; >> break; >> case _IO_seek_cur: >> - offset += fp->_IO_read_ptr - fp->_IO_read_base; >> + base = fp->_IO_read_ptr - fp->_IO_read_base; >> break; >> - default: /* case _IO_seek_set: */ >> + default: /* case _IO_seek_end: */ >> + base = cur_size; >> break; >> } >> - if (offset < 0) >> - return EOF; >> - if ((_IO_ssize_t) offset > cur_size >> - && enlarge_userbuf (fp, offset, 1) != 0) >> + _IO_ssize_t maxval = SSIZE_MAX - base; >> + if (offset < -base || offset > maxval) >> + { >> + __set_errno (EINVAL); >> + return EOF; >> + } >> + base += offset; >> + if (base > cur_size >> + && enlarge_userbuf (fp, base, 1) != 0) >> return EOF; >> - fp->_IO_read_ptr = fp->_IO_read_base + offset; >> + fp->_IO_read_ptr = fp->_IO_read_base + base; >> fp->_IO_read_end = fp->_IO_read_base + cur_size; >> - new_pos = offset; >> + new_pos = base; >> } >> >> /* Move the put pointer, if requested. */ >> if (mode & _IOS_OUTPUT) >> { >> + _IO_ssize_t base; >> switch (dir) >> { >> - case _IO_seek_end: >> - offset += cur_size; >> + case _IO_seek_set: >> + base = 0; >> break; >> case _IO_seek_cur: >> - offset += fp->_IO_write_ptr - fp->_IO_write_base; >> + base = fp->_IO_write_ptr - fp->_IO_write_base; >> break; >> - default: /* case _IO_seek_set: */ >> + default: /* case _IO_seek_end: */ >> + base = cur_size; >> break; >> } >> - if (offset < 0) >> - return EOF; >> - if ((_IO_ssize_t) offset > cur_size >> - && enlarge_userbuf (fp, offset, 0) != 0) >> + _IO_ssize_t maxval = SSIZE_MAX - base; >> + if (offset < -base || offset > maxval) >> + { >> + __set_errno (EINVAL); >> + return EOF; >> + } >> + base += offset; >> + if (base > cur_size >> + && enlarge_userbuf (fp, base, 0) != 0) >> return EOF; >> - fp->_IO_write_ptr = fp->_IO_write_base + offset; >> - new_pos = offset; >> + fp->_IO_write_ptr = fp->_IO_write_base + base; >> + new_pos = base; >> } >> } >> return new_pos; >> diff --git a/libio/tst-memstream3.c b/libio/tst-memstream3.c >> new file mode 100644 >> index 0000000..34b04e5 >> --- /dev/null >> +++ b/libio/tst-memstream3.c >> @@ -0,0 +1,165 @@ >> +/* Test for open_memstream implementation. >> + Copyright (C) 2016 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 >> + >> + >> +#ifndef CHAR_T >> +# define CHAR_T char >> +# define W(o) o >> +# define OPEN_MEMSTREAM open_memstream >> +# define PRINTF printf >> +# define FWRITE fwrite >> +# define FPUTC fputc >> +# define STRCMP strcmp >> +#endif >> + >> +#define S(s) S1 (s) >> +#define S1(s) #s >> + >> +static void >> +mcheck_abort (enum mcheck_status ev) >> +{ >> + printf ("mecheck failed with status %d\n", (int) ev); >> + exit (1); >> +} >> + >> +static void >> +error_printf (int line, const char *fmt, ...) >> +{ >> + va_list ap; >> + >> + printf ("error: %s:%i: ", __FILE__, line); >> + va_start (ap, fmt); >> + vprintf (fmt, ap); >> + va_end (ap); >> +} >> + >> +#define ERROR_RET1(...) \ >> + { error_printf(__LINE__, __VA_ARGS__); return 1; } >> + >> +static int >> +do_test_bz18241 (void) >> +{ >> + CHAR_T *buf; >> + size_t size; >> + >> + FILE *fp = OPEN_MEMSTREAM (&buf, &size); >> + if (fp == NULL) >> + ERROR_RET1 ("%s failed\n", S(OPEN_MEMSTREAM)); >> + >> + if (FPUTC (W('a'), fp) != W('a')) >> + ERROR_RET1 ("%s failed (errno = %d)\n", S(FPUTC), errno); >> + if (fflush (fp) != 0) >> + ERROR_RET1 ("fflush failed (errno = %d)\n", errno); >> + if (fseek (fp, -2, SEEK_SET) != -1) >> + ERROR_RET1 ("fseek failed (errno = %d)\n", errno); >> + if (errno != EINVAL) >> + ERROR_RET1 ("errno != EINVAL\n"); >> + if (ftell (fp) != 1) >> + ERROR_RET1 ("ftell failed (errno = %d)\n", errno); >> + if (ferror (fp) != 0) >> + ERROR_RET1 ("ferror != 0\n"); >> + >> + if (fseek (fp, -1, SEEK_CUR) == -1) >> + ERROR_RET1 ("fseek failed (errno = %d)\n", errno); >> + if (ftell (fp) != 0) >> + ERROR_RET1 ("ftell failed (errno = %d)\n", errno); >> + if (ferror (fp) != 0) >> + ERROR_RET1 ("ferror != 0\n"); >> + if (FPUTC (W('b'), fp) != W('b')) >> + ERROR_RET1 ("%s failed (errno = %d)\n", S(FPUTC), errno); >> + if (fflush (fp) != 0) >> + ERROR_RET1 ("fflush failed (errno = %d)\n", errno); >> + >> + if (fclose (fp) != 0) >> + ERROR_RET1 ("fclose failed (errno = %d\n", errno); >> + >> + if (STRCMP (buf, W("b")) != 0) >> + ERROR_RET1 ("%s failed\n", S(STRCMP)); >> + >> + free (buf); >> + >> + return 0; >> +} >> + >> +static int >> +do_test_bz20181 (void) >> +{ >> + CHAR_T *buf; >> + size_t size; >> + size_t ret; >> + >> + FILE *fp = OPEN_MEMSTREAM (&buf, &size); >> + if (fp == NULL) >> + ERROR_RET1 ("%s failed\n", S(OPEN_MEMSTREAM)); >> + >> + if ((ret = FWRITE (W("abc"), 1, 3, fp)) != 3) >> + ERROR_RET1 ("%s failed (errno = %d)\n", S(FWRITE), errno); >> + >> + if (fseek (fp, 0, SEEK_SET) != 0) >> + ERROR_RET1 ("fseek failed (errno = %d)\n", errno); >> + >> + if (FWRITE (W("z"), 1, 1, fp) != 1) >> + ERROR_RET1 ("%s failed (errno = %d)\n", S(FWRITE), errno); >> + >> + if (fflush (fp) != 0) >> + ERROR_RET1 ("fflush failed (errno = %d)\n", errno); >> + >> + /* Avoid truncating the buffer on close. */ >> + if (fseek (fp, 3, SEEK_SET) != 0) >> + ERROR_RET1 ("fseek failed (errno = %d)\n", errno); >> + >> + if (fclose (fp) != 0) >> + ERROR_RET1 ("fclose failed (errno = %d\n", errno); >> + >> + if (size != 3) >> + ERROR_RET1 ("size != 3\n"); >> + >> + if (buf[0] != W('z') >> + || buf[1] != W('b') >> + || buf[2] != W('c')) >> + { >> + PRINTF (W("error: buf {%c,%c,%c} != {z,b,c}\n"), >> + buf[0], buf[1], buf[2]); >> + return 1; >> + } >> + >> + free (buf); >> + >> + return 0; >> +} >> + >> +static int >> +do_test (void) >> +{ >> + int ret = 0; >> + >> + mcheck_pedantic (mcheck_abort); >> + >> + ret += do_test_bz18241 (); >> + ret += do_test_bz20181 (); >> + >> + return ret; >> +} >> + >> +#define TEST_FUNCTION do_test () >> +#include "../test-skeleton.c" >> diff --git a/libio/tst-wmemstream3.c b/libio/tst-wmemstream3.c >> new file mode 100644 >> index 0000000..190283a >> --- /dev/null >> +++ b/libio/tst-wmemstream3.c >> @@ -0,0 +1,44 @@ >> +/* Test for open_memstream implementation. >> + Copyright (C) 2016 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 >> + >> +/* Straighforward implementation so tst-memstream3 could use check >> + fwrite on open_memstream. */ >> +static size_t >> +fwwrite (const void *ptr, size_t size, size_t nmemb, FILE *arq) >> +{ >> + const wchar_t *wcs = (const wchar_t*) (ptr); >> + for (size_t s = 0; s < size; s++) >> + { >> + for (size_t n = 0; n < nmemb; n++) >> + if (fputwc (wcs[n], arq) == WEOF) >> + return n; >> + } >> + return size * nmemb; >> +} >> + >> +#define CHAR_T wchar_t >> +#define W(o) L##o >> +#define OPEN_MEMSTREAM open_wmemstream >> +#define PRINTF wprintf >> +#define FWRITE fwwrite >> +#define FPUTC fputwc >> +#define STRCMP wcscmp >> + >> +#include "tst-memstream3.c" >> diff --git a/libio/wmemstream.c b/libio/wmemstream.c >> index bf2a50b..fd01be0 100644 >> --- a/libio/wmemstream.c >> +++ b/libio/wmemstream.c >> @@ -112,8 +112,6 @@ _IO_wmem_sync (_IO_FILE *fp) >> _IO_wstr_overflow (fp, '\0'); >> --fp->_wide_data->_IO_write_ptr; >> } >> - else >> - *fp->_wide_data->_IO_write_ptr = '\0'; >> >> *mp->bufloc = fp->_wide_data->_IO_write_base; >> *mp->sizeloc = (fp->_wide_data->_IO_write_ptr >> diff --git a/libio/wstrops.c b/libio/wstrops.c >> index 09fa543..0b2bec3 100644 >> --- a/libio/wstrops.c >> +++ b/libio/wstrops.c >> @@ -169,7 +169,7 @@ _IO_wstr_count (_IO_FILE *fp) >> static int >> enlarge_userbuf (_IO_FILE *fp, _IO_off64_t offset, int reading) >> { >> - if ((_IO_ssize_t) offset <= _IO_blen (fp)) >> + if ((_IO_ssize_t) offset <= _IO_wblen (fp)) >> return 0; >> >> struct _IO_wide_data *wd = fp->_wide_data; >> @@ -235,6 +235,22 @@ enlarge_userbuf (_IO_FILE *fp, _IO_off64_t offset, int reading) >> return 0; >> } >> >> +static void >> +_IO_wstr_switch_to_get_mode (_IO_FILE *fp) >> +{ >> + if (_IO_in_backup (fp)) >> + fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_backup_base; >> + else >> + { >> + fp->_wide_data->_IO_read_base = fp->_wide_data->_IO_buf_base; >> + if (fp->_wide_data->_IO_write_ptr > fp->_wide_data->_IO_read_end) >> + fp->_wide_data->_IO_read_end = fp->_wide_data->_IO_write_ptr; >> + } >> + fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_write_ptr; >> + fp->_wide_data->_IO_read_end = fp->_wide_data->_IO_write_ptr; >> + >> + fp->_flags &= ~_IO_CURRENTLY_PUTTING; >> +} >> >> _IO_off64_t >> _IO_wstr_seekoff (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) >> @@ -244,15 +260,16 @@ _IO_wstr_seekoff (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) >> if (mode == 0 && (fp->_flags & _IO_TIED_PUT_GET)) >> mode = (fp->_flags & _IO_CURRENTLY_PUTTING ? _IOS_OUTPUT : _IOS_INPUT); >> >> + bool was_writing = (fp->_wide_data->_IO_write_ptr > >> + fp->_wide_data->_IO_write_base >> + || _IO_in_put_mode (fp)); >> + if (was_writing) >> + _IO_wstr_switch_to_get_mode (fp); >> + >> if (mode == 0) >> { >> - /* Don't move any pointers. But there is no clear indication what >> - mode FP is in. Let's guess. */ >> - if (fp->_IO_file_flags & _IO_NO_WRITES) >> - new_pos = fp->_wide_data->_IO_read_ptr - fp->_wide_data->_IO_read_base; >> - else >> - new_pos = (fp->_wide_data->_IO_write_ptr >> - - fp->_wide_data->_IO_write_base); >> + new_pos = (fp->_wide_data->_IO_write_ptr >> + - fp->_wide_data->_IO_write_base); >> } >> else >> { >> @@ -262,25 +279,32 @@ _IO_wstr_seekoff (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) >> /* Move the get pointer, if requested. */ >> if (mode & _IOS_INPUT) >> { >> + _IO_ssize_t base; >> switch (dir) >> { >> - case _IO_seek_end: >> - offset += cur_size; >> + case _IO_seek_set: >> + base = 0; >> break; >> case _IO_seek_cur: >> - offset += (fp->_wide_data->_IO_read_ptr >> - - fp->_wide_data->_IO_read_base); >> + base = (fp->_wide_data->_IO_read_ptr >> + - fp->_wide_data->_IO_read_base); >> break; >> - default: /* case _IO_seek_set: */ >> + default: /* case _IO_seek_end: */ >> + base = cur_size; >> break; >> } >> - if (offset < 0) >> - return EOF; >> - if ((_IO_ssize_t) offset > cur_size >> - && enlarge_userbuf (fp, offset, 1) != 0) >> + _IO_ssize_t maxval = SSIZE_MAX/sizeof (wchar_t) - base; >> + if (offset < -base || offset > maxval) >> + { >> + __set_errno (EINVAL); >> + return EOF; >> + } >> + base += offset; >> + if (base > cur_size >> + && enlarge_userbuf (fp, base, 1) != 0) >> return EOF; >> fp->_wide_data->_IO_read_ptr = (fp->_wide_data->_IO_read_base >> - + offset); >> + + base); >> fp->_wide_data->_IO_read_end = (fp->_wide_data->_IO_read_base >> + cur_size); >> new_pos = offset; >> @@ -289,26 +313,33 @@ _IO_wstr_seekoff (_IO_FILE *fp, _IO_off64_t offset, int dir, int mode) >> /* Move the put pointer, if requested. */ >> if (mode & _IOS_OUTPUT) >> { >> + _IO_ssize_t base; >> switch (dir) >> { >> - case _IO_seek_end: >> - offset += cur_size; >> + case _IO_seek_set: >> + base = 0; >> break; >> case _IO_seek_cur: >> - offset += (fp->_wide_data->_IO_write_ptr >> - - fp->_wide_data->_IO_write_base); >> + base = (fp->_wide_data->_IO_write_ptr >> + - fp->_wide_data->_IO_write_base); >> break; >> - default: /* case _IO_seek_set: */ >> + default: /* case _IO_seek_end: */ >> + base = cur_size; >> break; >> } >> - if (offset < 0) >> - return EOF; >> - if ((_IO_ssize_t) offset > cur_size >> - && enlarge_userbuf (fp, offset, 0) != 0) >> + _IO_ssize_t maxval = SSIZE_MAX/sizeof (wchar_t) - base; >> + if (offset < -base || offset > maxval) >> + { >> + __set_errno (EINVAL); >> + return EOF; >> + } >> + base += offset; >> + if (base > cur_size >> + && enlarge_userbuf (fp, base, 0) != 0) >> return EOF; >> fp->_wide_data->_IO_write_ptr = (fp->_wide_data->_IO_write_base >> - + offset); >> - new_pos = offset; >> + + base); >> + new_pos = base; >> } >> } >> return new_pos; >> diff --git a/manual/examples/memstrm.c b/manual/examples/memstrm.c >> index 0d443b1..5701ba1 100644 >> --- a/manual/examples/memstrm.c >> +++ b/manual/examples/memstrm.c >> @@ -27,10 +27,10 @@ main (void) >> stream = open_memstream (&bp, &size); >> fprintf (stream, "hello"); >> fflush (stream); >> - printf ("buf = `%s', size = %d\n", bp, size); >> + printf ("buf = `%s', size = %zu\n", bp, size); >> fprintf (stream, ", world"); >> fclose (stream); >> - printf ("buf = `%s', size = %d\n", bp, size); >> + printf ("buf = `%s', size = %zu\n", bp, size); >> >> return 0; >> } >>