diff options
Diffstat (limited to 'libio/wstrops.c')
-rw-r--r-- | libio/wstrops.c | 89 |
1 files changed, 60 insertions, 29 deletions
diff --git a/libio/wstrops.c b/libio/wstrops.c index 09fa543f77..0b2bec350c 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; |