/* Copyright (C) 1993-2024 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 . As a special exception, if you link the code in this file with files compiled with a GNU compiler to produce an executable, that does not cause the resulting executable to be covered by the GNU Lesser General Public License. This exception does not however invalidate any other reasons why the executable file might be covered by the GNU Lesser General Public License. This exception applies to code released by its copyright holders in files containing the exception. */ /* This is a compatibility file. If we don't build the libc with versioning don't compile this file. */ #include #if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1) #define _IO_USE_OLD_IO_FILE #include "libioP.h" #include #include #include #include #include #include #include /* An fstream can be in at most one of put mode, get mode, or putback mode. Putback mode is a variant of get mode. In a filebuf, there is only one current position, instead of two separate get and put pointers. In get mode, the current position is that of gptr(); in put mode that of pptr(). 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. If the field _fb._offset is >= 0, it gives the offset in the file as a whole corresponding to eGptr(). (?) PUT MODE: If a filebuf is in put mode, then all of _IO_read_ptr, _IO_read_end, and _IO_read_base are equal to each other. These are usually equal to _IO_buf_base, though not necessarily if we have switched from get mode to put mode. (The reason is to maintain the invariant that _IO_read_end corresponds to the external file position.) _IO_write_base is non-NULL and usually equal to _IO_buf_base. We also have _IO_write_end == _IO_buf_end, but only in fully buffered mode. The un-flushed character are those between _IO_write_base and _IO_write_ptr. GET MODE: If a filebuf is in get or putback mode, eback() != egptr(). In get mode, the unread characters are between gptr() and egptr(). The OS file position corresponds to that of egptr(). PUTBACK MODE: Putback mode is used to remember "excess" characters that have been sputbackc'd in a separate putback buffer. In putback mode, the get buffer points to the special putback buffer. The unread characters are the characters between gptr() and egptr() in the putback buffer, as well as the area between save_gptr() and save_egptr(), which point into the original reserve buffer. (The pointers save_gptr() and save_egptr() are the values of gptr() and egptr() at the time putback mode was entered.) The OS position corresponds to that of save_egptr(). LINE BUFFERED OUTPUT: During line buffered output, _IO_write_base==base() && epptr()==base(). However, ptr() may be anywhere between base() and ebuf(). This forces a call to filebuf::overflow(int C) on every put. If there is more space in the buffer, and C is not a '\n', then C is inserted, and pptr() incremented. UNBUFFERED STREAMS: If a filebuf is unbuffered(), the _shortbuf[1] is used as the buffer. */ #define CLOSED_FILEBUF_FLAGS \ (_IO_IS_FILEBUF+_IO_NO_READS+_IO_NO_WRITES+_IO_TIED_PUT_GET) void attribute_compat_text_section _IO_old_file_init_internal (struct _IO_FILE_plus *fp) { /* POSIX.1 allows another file handle to be used to change the position of our file descriptor. Hence we actually don't know the actual position before we do the first fseek (and until a following fflush). */ fp->file._old_offset = _IO_pos_BAD; fp->file._flags |= CLOSED_FILEBUF_FLAGS; _IO_link_in (fp); fp->file._vtable_offset = ((int) sizeof (struct _IO_FILE) - (int) sizeof (struct _IO_FILE_complete)); fp->file._fileno = -1; if (&_IO_stdin_used != NULL || !_IO_legacy_file ((FILE *) fp)) /* The object is dynamically allocated and large enough. Initialize the _mode element as well. */ ((struct _IO_FILE_complete *) fp)->_mode = -1; } void attribute_compat_text_section _IO_old_file_init (struct _IO_FILE_plus *fp) { IO_set_accept_foreign_vtables (&_IO_vtable_check); _IO_old_file_init_internal (fp); } int attribute_compat_text_section _IO_old_file_close_it (FILE *fp) { int write_status, close_status; if (!_IO_file_is_open (fp)) return EOF; write_status = _IO_old_do_flush (fp); _IO_unsave_markers (fp); close_status = ((fp->_flags2 & _IO_FLAGS2_NOCLOSE) == 0 ? _IO_SYSCLOSE (fp) : 0); /* Free buffer. */ _IO_setb (fp, NULL, NULL, 0); _IO_setg (fp, NULL, NULL, NULL); _IO_setp (fp, NULL, NULL); _IO_un_link ((struct _IO_FILE_plus *) fp); fp->_flags = _IO_MAGIC|CLOSED_FILEBUF_FLAGS; fp->_fileno = -1; fp->_old_offset = _IO_pos_BAD; return close_status ? close_status : write_status; } void attribute_compat_text_section _IO_old_file_finish (FILE *fp, int dummy) { if (_IO_file_is_open (fp)) { _IO_old_do_flush (fp); if (!(fp->_flags & _IO_DELETE_DONT_CLOSE)) _IO_SYSCLOSE (fp); } _IO_default_finish (fp, 0); } FILE * attribute_compat_text_section _IO_old_file_fopen (FILE *fp, const char *filename, const char *mode) { int oflags = 0, omode; int read_write, fdesc; int oprot = 0666; if (_IO_file_is_open (fp)) return 0; switch (*mode++) { case 'r': omode = O_RDONLY; read_write = _IO_NO_WRITES; break; case 'w': omode = O_WRONLY; oflags = O_CREAT|O_TRUNC; read_write = _IO_NO_READS; break; case 'a': omode = O_WRONLY; oflags = O_CREAT|O_APPEND; read_write = _IO_NO_READS|_IO_IS_APPENDING; break; default: __set_errno (EINVAL); return NULL; } if (mode[0] == '+' || (mode[0] == 'b' && mode[1] == '+')) { omode = O_RDWR; read_write &= _IO_IS_APPENDING; } fdesc = __open (filename, omode|oflags, oprot); if (fdesc < 0) return NULL; fp->_fileno = fdesc; _IO_mask_flags (fp, read_write,_IO_NO_READS+_IO_NO_WRITES+_IO_IS_APPENDING); if (read_write & _IO_IS_APPENDING) if (_IO_SEEKOFF (fp, (off_t)0, _IO_seek_end, _IOS_INPUT|_IOS_OUTPUT) == _IO_pos_BAD && errno != ESPIPE) return NULL; _IO_link_in ((struct _IO_FILE_plus *) fp); return fp; } FILE * attribute_compat_text_section _IO_old_file_attach (FILE *fp, int fd) { if (_IO_file_is_open (fp)) return NULL; fp->_fileno = fd; fp->_flags &= ~(_IO_NO_READS+_IO_NO_WRITES); fp->_flags |= _IO_DELETE_DONT_CLOSE; /* Get the current position of the file. */ /* We have to do that since that may be junk. */ fp->_old_offset = _IO_pos_BAD; if (_IO_SEEKOFF (fp, (off_t)0, _IO_seek_cur, _IOS_INPUT|_IOS_OUTPUT) == _IO_pos_BAD && errno != ESPIPE) return NULL; return fp; } FILE * attribute_compat_text_section _IO_old_file_setbuf (FILE *fp, char *p, ssize_t len) { if (_IO_default_setbuf (fp, p, len) == NULL) return NULL; fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end = fp->_IO_buf_base; _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base); return fp; } static int old_do_write (FILE *, const char *, size_t); /* Write TO_DO bytes from DATA to FP. Then mark FP as having empty buffers. */ int attribute_compat_text_section _IO_old_do_write (FILE *fp, const char *data, size_t to_do) { return (to_do == 0 || (size_t) old_do_write (fp, data, to_do) == to_do) ? 0 : EOF; } static int attribute_compat_text_section old_do_write (FILE *fp, const char *data, size_t to_do) { size_t count; if (fp->_flags & _IO_IS_APPENDING) /* On a system without a proper O_APPEND implementation, you would need to sys_seek(0, SEEK_END) here, but is not needed nor desirable for Unix- or Posix-like systems. Instead, just indicate that offset (before and after) is unpredictable. */ fp->_old_offset = _IO_pos_BAD; else if (fp->_IO_read_end != fp->_IO_write_base) { off_t new_pos = _IO_SYSSEEK (fp, fp->_IO_write_base - fp->_IO_read_end, 1); if (new_pos == _IO_pos_BAD) return 0; fp->_old_offset = new_pos; } count = _IO_SYSWRITE (fp, data, to_do); if (fp->_cur_column && count) fp->_cur_column = _IO_adjust_column (fp->_cur_column - 1, data, count) + 1; _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base); fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_buf_base; fp->_IO_write_end = ((fp->_flags & (_IO_LINE_BUF | _IO_UNBUFFERED)) ? fp->_IO_buf_base : fp->_IO_buf_end); return count; } int attribute_compat_text_section _IO_old_file_underflow (FILE *fp) { ssize_t count; /* C99 requires EOF to be "sticky". */ if (fp->_flags & _IO_EOF_SEEN) return EOF; if (fp->_flags & _IO_NO_READS) { fp->_flags |= _IO_ERR_SEEN; __set_errno (EBADF); return EOF; } if (fp->_IO_read_ptr < fp->_IO_read_end) return *(unsigned char *) fp->_IO_read_ptr; if (fp->_IO_buf_base == NULL) { /* Maybe we already have a push back pointer. */ if (fp->_IO_save_base != NULL) { free (fp->_IO_save_base); fp->_flags &= ~_IO_IN_BACKUP; } _IO_doallocbuf (fp); } /* Flush all line buffered files before reading. */ /* FIXME This can/should be moved to genops ?? */ if (fp->_flags & (_IO_LINE_BUF|_IO_UNBUFFERED)) _IO_flush_all_linebuffered (); _IO_switch_to_get_mode (fp); /* This is very tricky. We have to adjust those pointers before we call _IO_SYSREAD () since we may longjump () out while waiting for input. Those pointers may be screwed up. H.J. */ fp->_IO_read_base = fp->_IO_read_ptr = fp->_IO_buf_base; fp->_IO_read_end = fp->_IO_buf_base; fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end = fp->_IO_buf_base; count = _IO_SYSREAD (fp, fp->_IO_buf_base, fp->_IO_buf_end - fp->_IO_buf_base); if (count <= 0) { if (count == 0) fp->_flags |= _IO_EOF_SEEN; else fp->_flags |= _IO_ERR_SEEN, count = 0; } fp->_IO_read_end += count; if (count == 0) return EOF; if (fp->_old_offset != _IO_pos_BAD) _IO_pos_adjust (fp->_old_offset, count); return *(unsigned char *) fp->_IO_read_ptr; } int attribute_compat_text_section _IO_old_file_overflow (FILE *f, int ch) { if (f->_flags & _IO_NO_WRITES) /* SET ERROR */ { f->_flags |= _IO_ERR_SEEN; __set_errno (EBADF); return EOF; } /* If currently reading or no buffer allocated. */ if ((f->_flags & _IO_CURRENTLY_PUTTING) == 0) { /* Allocate a buffer if needed. */ if (f->_IO_write_base == 0) { _IO_doallocbuf (f); _IO_setg (f, f->_IO_buf_base, f->_IO_buf_base, f->_IO_buf_base); } /* Otherwise must be currently reading. If _IO_read_ptr (and hence also _IO_read_end) is at the buffer end, logically slide the buffer forwards one block (by setting the read pointers to all point at the beginning of the block). This makes room for subsequent output. Otherwise, set the read pointers to _IO_read_end (leaving that alone, so it can continue to correspond to the external position). */ if (f->_IO_read_ptr == f->_IO_buf_end) f->_IO_read_end = f->_IO_read_ptr = f->_IO_buf_base; f->_IO_write_ptr = f->_IO_read_ptr; f->_IO_write_base = f->_IO_write_ptr; f->_IO_write_end = f->_IO_buf_end; f->_IO_read_base = f->_IO_read_ptr = f->_IO_read_end; if (f->_flags & (_IO_LINE_BUF | _IO_UNBUFFERED)) f->_IO_write_end = f->_IO_write_ptr; f->_flags |= _IO_CURRENTLY_PUTTING; } if (ch == EOF) return _IO_old_do_flush (f); if (f->_IO_write_ptr == f->_IO_buf_end ) /* Buffer is really full */ if (_IO_old_do_flush (f) == EOF) return EOF; *f->_IO_write_ptr++ = ch; if ((f->_flags & _IO_UNBUFFERED) || ((f->_flags & _IO_LINE_BUF) && ch == '\n')) if (_IO_old_do_flush (f) == EOF) return EOF; return (unsigned char) ch; } int attribute_compat_text_section _IO_old_file_sync (FILE *fp) { ssize_t delta; int retval = 0; /* char* ptr = cur_ptr(); */ if (fp->_IO_write_ptr > fp->_IO_write_base) if (_IO_old_do_flush(fp)) return EOF; delta = fp->_IO_read_ptr - fp->_IO_read_end; if (delta != 0) { #ifdef TODO if (_IO_in_backup (fp)) delta -= eGptr () - Gbase (); #endif off_t new_pos = _IO_SYSSEEK (fp, delta, 1); if (new_pos != (off_t) EOF) fp->_IO_read_end = fp->_IO_read_ptr; else if (errno == ESPIPE) ; /* Ignore error from unseekable devices. */ else retval = EOF; } if (retval != EOF) fp->_old_offset = _IO_pos_BAD; /* FIXME: Cleanup - can this be shared? */ /* setg(base(), ptr, ptr); */ return retval; } off64_t attribute_compat_text_section _IO_old_file_seekoff (FILE *fp, off64_t offset, int dir, int mode) { off_t result; off64_t delta, new_offset; long count; /* POSIX.1 8.2.3.7 says that after a call the fflush() the file offset of the underlying file must be exact. */ int must_be_exact = (fp->_IO_read_base == fp->_IO_read_end && fp->_IO_write_base == fp->_IO_write_ptr); if (mode == 0) dir = _IO_seek_cur, offset = 0; /* Don't move any pointers. */ /* Flush unwritten characters. (This may do an unneeded write if we seek within the buffer. But to be able to switch to reading, we would need to set egptr to pptr. That can't be done in the current design, which assumes file_ptr() is eGptr. Anyway, since we probably end up flushing when we close(), it doesn't make much difference.) FIXME: simulate mem-mapped files. */ if (fp->_IO_write_ptr > fp->_IO_write_base || _IO_in_put_mode (fp)) if (_IO_switch_to_get_mode (fp)) return EOF; if (fp->_IO_buf_base == NULL) { /* It could be that we already have a pushback buffer. */ if (fp->_IO_read_base != NULL) { free (fp->_IO_read_base); fp->_flags &= ~_IO_IN_BACKUP; } _IO_doallocbuf (fp); _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base); } switch (dir) { case _IO_seek_cur: /* Adjust for read-ahead (bytes is buffer). */ offset -= fp->_IO_read_end - fp->_IO_read_ptr; if (fp->_old_offset == _IO_pos_BAD) goto dumb; /* Make offset absolute, assuming current pointer is file_ptr(). */ offset += fp->_old_offset; dir = _IO_seek_set; break; case _IO_seek_set: break; case _IO_seek_end: { struct __stat64_t64 st; if (_IO_SYSSTAT (fp, &st) == 0 && S_ISREG (st.st_mode)) { offset += st.st_size; dir = _IO_seek_set; } else goto dumb; } } /* At this point, dir==_IO_seek_set. */ /* If we are only interested in the current position we've found it now. */ if (mode == 0) return offset; /* If destination is within current buffer, optimize: */ if (fp->_old_offset != _IO_pos_BAD && fp->_IO_read_base != NULL && !_IO_in_backup (fp)) { /* Offset relative to start of main get area. */ off_t rel_offset = (offset - fp->_old_offset + (fp->_IO_read_end - fp->_IO_read_base)); if (rel_offset >= 0) { if (rel_offset <= fp->_IO_read_end - fp->_IO_read_base) { _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + rel_offset, fp->_IO_read_end); _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); { _IO_mask_flags (fp, 0, _IO_EOF_SEEN); goto resync; } } #ifdef TODO /* If we have streammarkers, seek forward by reading ahead. */ if (_IO_have_markers (fp)) { int to_skip = rel_offset - (fp->_IO_read_ptr - fp->_IO_read_base); if (ignore (to_skip) != to_skip) goto dumb; _IO_mask_flags (fp, 0, _IO_EOF_SEEN); goto resync; } #endif } #ifdef TODO if (rel_offset < 0 && rel_offset >= Bbase () - Bptr ()) { if (!_IO_in_backup (fp)) _IO_switch_to_backup_area (fp); gbump (fp->_IO_read_end + rel_offset - fp->_IO_read_ptr); _IO_mask_flags (fp, 0, _IO_EOF_SEEN); goto resync; } #endif } #ifdef TODO _IO_unsave_markers (fp); #endif if (fp->_flags & _IO_NO_READS) goto dumb; /* Try to seek to a block boundary, to improve kernel page management. */ new_offset = offset & ~(fp->_IO_buf_end - fp->_IO_buf_base - 1); delta = offset - new_offset; if (delta > fp->_IO_buf_end - fp->_IO_buf_base) { new_offset = offset; delta = 0; } result = _IO_SYSSEEK (fp, new_offset, 0); if (result < 0) return EOF; if (delta == 0) count = 0; else { count = _IO_SYSREAD (fp, fp->_IO_buf_base, (must_be_exact ? delta : fp->_IO_buf_end - fp->_IO_buf_base)); if (count < delta) { /* We weren't allowed to read, but try to seek the remainder. */ offset = count == EOF ? delta : delta-count; dir = _IO_seek_cur; goto dumb; } } _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base + delta, fp->_IO_buf_base + count); _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); fp->_old_offset = result + count; _IO_mask_flags (fp, 0, _IO_EOF_SEEN); return offset; dumb: _IO_unsave_markers (fp); result = _IO_SYSSEEK (fp, offset, dir); if (result != EOF) { _IO_mask_flags (fp, 0, _IO_EOF_SEEN); fp->_old_offset = result; _IO_setg (fp, fp->_IO_buf_base, fp->_IO_buf_base, fp->_IO_buf_base); _IO_setp (fp, fp->_IO_buf_base, fp->_IO_buf_base); } return result; resync: /* We need to do it since it is possible that the file offset in the kernel may be changed behind our back. It may happen when we fopen a file and then do a fork. One process may access the file and the kernel file offset will be changed. */ if (fp->_old_offset >= 0) _IO_SYSSEEK (fp, fp->_old_offset, 0); return offset; } ssize_t attribute_compat_text_section _IO_old_file_write (FILE *f, const void *data, ssize_t n) { ssize_t to_do = n; while (to_do > 0) { ssize_t count = __write (f->_fileno, data, to_do); if (count == EOF) { f->_flags |= _IO_ERR_SEEN; break; } to_do -= count; data = (void *) ((char *) data + count); } n -= to_do; if (f->_old_offset >= 0) f->_old_offset += n; return n; } size_t attribute_compat_text_section _IO_old_file_xsputn (FILE *f, const void *data, size_t n) { const char *s = (char *) data; size_t to_do = n; int must_flush = 0; size_t count = 0; if (n <= 0) return 0; /* This is an optimized implementation. If the amount to be written straddles a block boundary (or the filebuf is unbuffered), use sys_write directly. */ /* First figure out how much space is available in the buffer. */ if ((f->_flags & _IO_LINE_BUF) && (f->_flags & _IO_CURRENTLY_PUTTING)) { count = f->_IO_buf_end - f->_IO_write_ptr; if (count >= n) { const char *p; for (p = s + n; p > s; ) { if (*--p == '\n') { count = p - s + 1; must_flush = 1; break; } } } } else if (f->_IO_write_end > f->_IO_write_ptr) count = f->_IO_write_end - f->_IO_write_ptr; /* Space available. */ /* Then fill the buffer. */ if (count > 0) { if (count > to_do) count = to_do; if (count > 20) { f->_IO_write_ptr = __mempcpy (f->_IO_write_ptr, s, count); s += count; } else { char *p = f->_IO_write_ptr; int i = (int) count; while (--i >= 0) *p++ = *s++; f->_IO_write_ptr = p; } to_do -= count; } if (to_do + must_flush > 0) { size_t block_size, do_write; /* Next flush the (full) buffer. */ if (__overflow (f, EOF) == EOF) return to_do == 0 ? EOF : n - to_do; /* Try to maintain alignment: write a whole number of blocks. dont_write is what gets left over. */ block_size = f->_IO_buf_end - f->_IO_buf_base; do_write = to_do - (block_size >= 128 ? to_do % block_size : 0); if (do_write) { count = old_do_write (f, s, do_write); to_do -= count; if (count < do_write) return n - to_do; } /* Now write out the remainder. Normally, this will fit in the buffer, but it's somewhat messier for line-buffered files, so we let _IO_default_xsputn handle the general case. */ if (to_do) to_do -= _IO_default_xsputn (f, s+do_write, to_do); } return n - to_do; } compat_symbol (libc, _IO_old_do_write, _IO_do_write, GLIBC_2_0); compat_symbol (libc, _IO_old_file_attach, _IO_file_attach, GLIBC_2_0); compat_symbol (libc, _IO_old_file_close_it, _IO_file_close_it, GLIBC_2_0); compat_symbol (libc, _IO_old_file_finish, _IO_file_finish, GLIBC_2_0); compat_symbol (libc, _IO_old_file_fopen, _IO_file_fopen, GLIBC_2_0); compat_symbol (libc, _IO_old_file_init, _IO_file_init, GLIBC_2_0); compat_symbol (libc, _IO_old_file_setbuf, _IO_file_setbuf, GLIBC_2_0); compat_symbol (libc, _IO_old_file_sync, _IO_file_sync, GLIBC_2_0); compat_symbol (libc, _IO_old_file_overflow, _IO_file_overflow, GLIBC_2_0); compat_symbol (libc, _IO_old_file_seekoff, _IO_file_seekoff, GLIBC_2_0); compat_symbol (libc, _IO_old_file_underflow, _IO_file_underflow, GLIBC_2_0); compat_symbol (libc, _IO_old_file_write, _IO_file_write, GLIBC_2_0); compat_symbol (libc, _IO_old_file_xsputn, _IO_file_xsputn, GLIBC_2_0); #endif