diff options
Diffstat (limited to 'libio')
| -rw-r--r-- | libio/Makefile | 4 | ||||
| -rw-r--r-- | libio/fileops.c | 12 | ||||
| -rw-r--r-- | libio/tst-ftell-append.c | 169 | ||||
| -rw-r--r-- | libio/wfileops.c | 13 |
4 files changed, 193 insertions, 5 deletions
diff --git a/libio/Makefile b/libio/Makefile index cca03454fc..b324ccc519 100644 --- a/libio/Makefile +++ b/libio/Makefile @@ -60,7 +60,8 @@ tests = tst_swprintf tst_wprintf tst_swscanf tst_wscanf tst_getwc tst_putwc \ tst-wmemstream1 tst-wmemstream2 \ 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 + tst-fwrite-error tst-ftell-partial-wide tst-ftell-active-handler \ + tst-ftell-append ifeq (yes,$(build-shared)) # Add test-fopenloc only if shared library is enabled since it depends on # shared localedata objects. @@ -160,6 +161,7 @@ tst-fgetwc-ENV = LOCPATH=$(common-objpfx)localedata tst-fseek-ENV = LOCPATH=$(common-objpfx)localedata tst-ftell-partial-wide-ENV = LOCPATH=$(common-objpfx)localedata tst-ftell-active-handler-ENV = LOCPATH=$(common-objpfx)localedata +tst-ftell-append-ENV = LOCPATH=$(common-objpfx)localedata generated += tst-fopenloc.mtrace tst-fopenloc.check diff --git a/libio/fileops.c b/libio/fileops.c index cf68dbfe52..204cfeaa35 100644 --- a/libio/fileops.c +++ b/libio/fileops.c @@ -91,7 +91,9 @@ extern struct __gconv_trans_data __libio_translit attribute_hidden; The position in the buffer that corresponds to the position in external file system is normally _IO_read_end, except in putback - mode, when it is _IO_save_end. + mode, when it is _IO_save_end and also when the file is in append mode, + since switching from read to write mode automatically sends the position in + the external file system to the end of file. If the field _fb._offset is >= 0, it gives the offset in the file as a whole corresponding to eGptr(). (?) @@ -966,6 +968,14 @@ do_ftell (_IO_FILE *fp) /* Adjust for unflushed data. */ if (!was_writing) offset -= fp->_IO_read_end - fp->_IO_read_ptr; + /* We don't trust _IO_read_end to represent the current file offset when + writing in append mode because the value would have to be shifted to + the end of the file during a flush. Use the write base instead, along + with the new offset we got above when we did a seek to the end of the + file. */ + else if (append_mode) + offset += fp->_IO_write_ptr - fp->_IO_write_base; + /* For all other modes, _IO_read_end represents the file offset. */ else offset += fp->_IO_write_ptr - fp->_IO_read_end; } diff --git a/libio/tst-ftell-append.c b/libio/tst-ftell-append.c new file mode 100644 index 0000000000..604dc0342c --- /dev/null +++ b/libio/tst-ftell-append.c @@ -0,0 +1,169 @@ +/* Verify that ftell returns the correct value after a read and a write on a + file opened in a+ mode. + Copyright (C) 2014 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 + <http://www.gnu.org/licenses/>. */ + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <locale.h> +#include <wchar.h> + +/* data points to either char_data or wide_data, depending on whether we're + testing regular file mode or wide mode respectively. Similarly, + fputs_func points to either fputs or fputws. data_len keeps track of the + length of the current data and file_len maintains the current file + length. */ +#define BUF_LEN 4 +static void *buf; +static char char_buf[BUF_LEN]; +static wchar_t wide_buf[BUF_LEN]; +static const void *data; +static const char *char_data = "abcdefghijklmnopqrstuvwxyz"; +static const wchar_t *wide_data = L"abcdefghijklmnopqrstuvwxyz"; +static size_t data_len; +static size_t file_len; + +typedef int (*fputs_func_t) (const void *data, FILE *fp); +fputs_func_t fputs_func; + +typedef void *(*fgets_func_t) (void *s, int size, FILE *stream); +fgets_func_t fgets_func; + +static int do_test (void); + +#define TEST_FUNCTION do_test () +#include "../test-skeleton.c" + +static FILE * +init_file (const char *filename) +{ + FILE *fp = fopen (filename, "w"); + if (fp == NULL) + { + printf ("fopen: %m\n"); + return NULL; + } + + int written = fputs_func (data, fp); + + if (written == EOF) + { + printf ("fputs failed to write data\n"); + fclose (fp); + return NULL; + } + + file_len = data_len; + + fclose (fp); + + fp = fopen (filename, "a+"); + if (fp == NULL) + { + printf ("fopen(a+): %m\n"); + return NULL; + } + + return fp; +} + +static int +do_one_test (const char *filename) +{ + FILE *fp = init_file (filename); + + if (fp == NULL) + return 1; + + void *ret = fgets_func (buf, BUF_LEN, fp); + + if (ret == NULL) + { + printf ("read failed: %m\n"); + fclose (fp); + return 1; + } + + int written = fputs_func (data, fp); + + if (written == EOF) + { + printf ("fputs failed to write data\n"); + fclose (fp); + return 1; + } + + file_len += data_len; + + long off = ftell (fp); + + if (off != file_len) + { + printf ("Incorrect offset %ld, expected %zu\n", off, file_len); + fclose (fp); + return 1; + } + else + printf ("Correct offset %ld after write.\n", off); + + return 0; +} + +/* Run the tests for regular files and wide mode files. */ +static int +do_test (void) +{ + int ret = 0; + char *filename; + int fd = create_temp_file ("tst-ftell-append-tmp.", &filename); + + if (fd == -1) + { + printf ("create_temp_file: %m\n"); + return 1; + } + + close (fd); + + /* Tests for regular files. */ + puts ("Regular mode:"); + fputs_func = (fputs_func_t) fputs; + fgets_func = (fgets_func_t) fgets; + data = char_data; + buf = char_buf; + data_len = strlen (char_data); + ret |= do_one_test (filename); + + /* Tests for wide files. */ + puts ("Wide mode:"); + if (setlocale (LC_ALL, "en_US.UTF-8") == NULL) + { + printf ("Cannot set en_US.UTF-8 locale.\n"); + return 1; + } + fputs_func = (fputs_func_t) fputws; + fgets_func = (fgets_func_t) fgetws; + data = wide_data; + buf = wide_buf; + data_len = wcslen (wide_data); + ret |= do_one_test (filename); + + return ret; +} diff --git a/libio/wfileops.c b/libio/wfileops.c index 3199861b4d..f123add354 100644 --- a/libio/wfileops.c +++ b/libio/wfileops.c @@ -713,9 +713,16 @@ do_ftell_wide (_IO_FILE *fp) offset += outstop - out; } - /* _IO_read_end coincides with fp._offset, so the actual file - position is fp._offset - (_IO_read_end - new_write_ptr). */ - offset -= fp->_IO_read_end - fp->_IO_write_ptr; + /* We don't trust _IO_read_end to represent the current file offset + when writing in append mode because the value would have to be + shifted to the end of the file during a flush. Use the write base + instead, along with the new offset we got above when we did a seek + to the end of the file. */ + if (append_mode) + offset += fp->_IO_write_ptr - fp->_IO_write_base; + /* For all other modes, _IO_read_end represents the file offset. */ + else + offset += fp->_IO_write_ptr - fp->_IO_read_end; } } |