From 4573c6b09884a93fffa3a754678ef881cadebfb3 Mon Sep 17 00:00:00 2001 From: Siddhesh Poyarekar Date: Fri, 28 Sep 2012 18:20:40 +0530 Subject: Adjust wide data buffer pointers during fseek and ftell [BZ #14543] Set the internal buffer state correctly whenever the external buffer state is modified by fseek by either computing the current _IO_read_ptr/end for the internal buffer based on the new _IO_read_ptr in the external buffer or converting the content read into the external buffer, up to the extent of the requested fseek offset. --- libio/Makefile | 3 +- libio/tst-fseek.c | 173 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ libio/wfileops.c | 59 +++++++++++++++++++ 3 files changed, 234 insertions(+), 1 deletion(-) create mode 100644 libio/tst-fseek.c (limited to 'libio') diff --git a/libio/Makefile b/libio/Makefile index e2a7efdc1c..0d28cea59c 100644 --- a/libio/Makefile +++ b/libio/Makefile @@ -59,7 +59,7 @@ tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc \ tst-memstream1 tst-memstream2 \ tst-wmemstream1 tst-wmemstream2 \ bug-memstream1 bug-wmemstream1 \ - tst-setvbuf1 tst-popen1 tst-fgetwc bug-wsetpos bug-fclose1 + tst-setvbuf1 tst-popen1 tst-fgetwc bug-wsetpos bug-fclose1 tst-fseek ifeq (yes,$(build-shared)) # Add test-fopenloc only if shared library is enabled since it depends on # shared localedata objects. @@ -158,6 +158,7 @@ bug-ungetwc2-ENV = LOCPATH=$(common-objpfx)localedata tst-swscanf-ENV = LOCPATH=$(common-objpfx)localedata bug-ftell-ENV = LOCPATH=$(common-objpfx)localedata tst-fgetwc-ENV = LOCPATH=$(common-objpfx)localedata +tst-fseek-ENV = LOCPATH=$(common-objpfx)localedata generated = tst-fopenloc.mtrace tst-fopenloc.check diff --git a/libio/tst-fseek.c b/libio/tst-fseek.c new file mode 100644 index 0000000000..457a087785 --- /dev/null +++ b/libio/tst-fseek.c @@ -0,0 +1,173 @@ +/* Verify that fseek/ftell combination works for wide chars. + Copyright (C) 2012 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 +#include +#include +#include + +/* Defined in test-skeleton.c. */ +static int create_temp_file (const char *base, char **filename); + + +static int +do_seek_end (FILE *fp) +{ + long save; + + if (fputws (L"abc\n", fp) == -1) + { + printf ("do_seek_end: fputws: %s\n", strerror (errno)); + return 1; + } + + save = ftell (fp); + rewind (fp); + + if (fseek (fp, 0, SEEK_END) == -1) + { + printf ("do_seek_end: fseek: %s\n", strerror (errno)); + return 1; + } + + if (save != ftell (fp)) + { + printf ("save = %ld, ftell = %ld\n", save, ftell (fp)); + return 1; + } + + return 0; +} + +int +do_seek_set (FILE *fp) +{ + long save1, save2; + + if (fputws (L"ゅう\n", fp) == -1) + { + printf ("seek_set: fputws(1): %s\n", strerror (errno)); + return 1; + } + + save1 = ftell (fp); + + if (fputws (L"ゅう\n", fp) == -1) + { + printf ("seek_set: fputws(2): %s\n", strerror (errno)); + return 1; + } + + save2 = ftell (fp); + + if (fputws (L"ゅう\n", fp) == -1) + { + printf ("seek_set: fputws(3): %s\n", strerror (errno)); + return 1; + } + + if (fseek (fp, save1, SEEK_SET) == -1) + { + printf ("seek_set: fseek(1): %s\n", strerror (errno)); + return 1; + } + + if (save1 != ftell (fp)) + { + printf ("save1 = %ld, ftell = %ld\n", save1, ftell (fp)); + return 1; + } + + if (fseek (fp, save2, SEEK_SET) == -1) + { + printf ("seek_set: fseek(2): %s\n", strerror (errno)); + return 1; + } + + if (save2 != ftell (fp)) + { + printf ("save2 = %ld, ftell = %ld\n", save2, ftell (fp)); + return 1; + } + + return 0; +} + +static int +do_test (void) +{ + if (setlocale (LC_ALL, "ja_JP.UTF-8") == NULL) + { + printf ("Cannot set ja_JP.UTF-8 locale.\n"); + exit (1); + } + + /* Retain messages in English. */ + if (setlocale (LC_MESSAGES, "en_US.ISO-8859-1") == NULL) + { + printf ("Cannot set LC_MESSAGES to en_US.ISO-8859-1 locale.\n"); + exit (1); + } + + int ret = 0; + char *filename; + int fd = create_temp_file ("tst-fseek.out", &filename); + + if (fd == -1) + return 1; + + FILE *fp = fdopen (fd, "w+"); + if (fp == NULL) + { + printf ("seek_set: fopen: %s\n", strerror (errno)); + close (fd); + return 1; + } + + if (do_seek_set (fp)) + { + printf ("SEEK_SET test failed\n"); + ret = 1; + } + + /* Reopen the file. */ + fclose (fp); + fp = fopen (filename, "w+"); + if (fp == NULL) + { + printf ("seek_end: fopen: %s\n", strerror (errno)); + return 1; + } + + if (do_seek_end (fp)) + { + printf ("SEEK_END test failed\n"); + ret = 1; + } + + fclose (fp); + + return ret; +} + + +#define TEST_FUNCTION do_test () +#include "../test-skeleton.c" diff --git a/libio/wfileops.c b/libio/wfileops.c index b790029ffc..d3f46b2ed1 100644 --- a/libio/wfileops.c +++ b/libio/wfileops.c @@ -545,6 +545,57 @@ _IO_wfile_sync (fp) } libc_hidden_def (_IO_wfile_sync) +/* Adjust the internal buffer pointers to reflect the state in the external + buffer. The content between fp->_IO_read_base and fp->_IO_read_ptr is + assumed to be converted and available in the range + fp->_wide_data->_IO_read_base and fp->_wide_data->_IO_read_end. + + Returns 0 on success and -1 on error with the _IO_ERR_SEEN flag set. */ +static inline int +adjust_wide_data (_IO_FILE *fp, bool do_convert) +{ + struct _IO_codecvt *cv = fp->_codecvt; + + int clen = (*cv->__codecvt_do_encoding) (cv); + + /* Take the easy way out for constant length encodings if we don't need to + convert. */ + if (!do_convert && clen > 0) + { + fp->_wide_data->_IO_read_end += ((fp->_IO_read_ptr - fp->_IO_read_base) + / clen); + goto done; + } + + enum __codecvt_result status; + const char *read_stop = (const char *) fp->_IO_read_base; + do + { + + fp->_wide_data->_IO_last_state = fp->_wide_data->_IO_state; + status = (*cv->__codecvt_do_in) (cv, &fp->_wide_data->_IO_state, + fp->_IO_read_base, fp->_IO_read_ptr, + &read_stop, + fp->_wide_data->_IO_read_base, + fp->_wide_data->_IO_buf_end, + &fp->_wide_data->_IO_read_end); + + /* Should we return EILSEQ? */ + if (__builtin_expect (status == __codecvt_error, 0)) + { + fp->_flags |= _IO_ERR_SEEN; + return -1; + } + } + while (__builtin_expect (status == __codecvt_partial, 0)); + +done: + /* Now seek to _IO_read_end to behave as if we have read it all in. */ + fp->_wide_data->_IO_read_ptr = fp->_wide_data->_IO_read_end; + + return 0; +} + _IO_off64_t _IO_wfile_seekoff (fp, offset, dir, mode) _IO_FILE *fp; @@ -693,6 +744,10 @@ _IO_wfile_seekoff (fp, offset, dir, mode) fp->_wide_data->_IO_buf_base); _IO_wsetp (fp, fp->_wide_data->_IO_buf_base, fp->_wide_data->_IO_buf_base); + + if (adjust_wide_data (fp, false)) + goto dumb; + _IO_mask_flags (fp, 0, _IO_EOF_SEEN); goto resync; } @@ -733,6 +788,10 @@ _IO_wfile_seekoff (fp, offset, dir, mode) _IO_wsetg (fp, fp->_wide_data->_IO_buf_base, fp->_wide_data->_IO_buf_base, fp->_wide_data->_IO_buf_base); _IO_wsetp (fp, fp->_wide_data->_IO_buf_base, fp->_wide_data->_IO_buf_base); + + if (adjust_wide_data (fp, true)) + goto dumb; + fp->_offset = result + count; _IO_mask_flags (fp, 0, _IO_EOF_SEEN); return offset; -- cgit 1.4.1