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-rw-r--r--libio/fileops.c738
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diff --git a/libio/fileops.c b/libio/fileops.c
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--- /dev/null
+++ b/libio/fileops.c
@@ -0,0 +1,738 @@
+/*
+Copyright (C) 1993, 1995 Free Software Foundation
+
+This file is part of the GNU IO Library. This library is free
+software; you can redistribute it and/or modify it under the
+terms of the GNU General Public License as published by the
+Free Software Foundation; either version 2, or (at your option)
+any later version.
+
+This 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 General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this library; see the file COPYING. If not, write to the Free
+Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+
+As a special exception, if you link this library with files
+compiled with a GNU compiler to produce an executable, this does not cause
+the resulting executable to be covered by the GNU General Public License.
+This exception does not however invalidate any other reasons why
+the executable file might be covered by the GNU General Public License. */
+
+/* written by Per Bothner (bothner@cygnus.com) */
+
+#define _POSIX_SOURCE
+#include "libioP.h"
+#include <fcntl.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <string.h>
+#include <errno.h>
+#ifndef errno
+extern int errno;
+#endif
+
+/* 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 posistion
+ 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 file_ptr().
+ This 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, pbase() is non-NULL and equal to base().
+ Also, epptr() == ebuf().
+ Also, eback() == gptr() && gptr() == egptr().
+ The un-flushed character are those between pbase() and pptr().
+ 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, pbase()==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
+DEFUN(_IO_file_init, (fp),
+ register _IO_FILE *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->_offset = _IO_pos_BAD;
+ fp->_IO_file_flags |= CLOSED_FILEBUF_FLAGS;
+
+ _IO_link_in(fp);
+ fp->_fileno = -1;
+}
+
+int
+DEFUN(_IO_file_close_it, (fp),
+ register _IO_FILE* fp)
+{
+ int sync_status, close_status;
+ if (!_IO_file_is_open(fp))
+ return EOF;
+
+ sync_status = _IO_file_sync (fp);
+
+ _IO_unsave_markers(fp);
+
+ close_status = _IO_SYSCLOSE (fp);
+
+ /* Free buffer. */
+ _IO_setb(fp, NULL, NULL, 0);
+ _IO_setg(fp, NULL, NULL, NULL);
+ _IO_setp(fp, NULL, NULL);
+
+ _IO_un_link(fp);
+ fp->_flags = _IO_MAGIC|CLOSED_FILEBUF_FLAGS;
+ fp->_fileno = EOF;
+ fp->_offset = _IO_pos_BAD;
+
+ return close_status ? close_status : sync_status;
+}
+
+void
+DEFUN(_IO_file_finish, (fp),
+ register _IO_FILE* fp)
+{
+ if (_IO_file_is_open(fp))
+ {
+ _IO_do_flush (fp);
+ if (!(fp->_flags & _IO_DELETE_DONT_CLOSE))
+ _IO_SYSCLOSE (fp);
+ }
+ _IO_default_finish(fp);
+}
+
+_IO_FILE *
+DEFUN(_IO_file_fopen, (fp, filename, mode),
+ register _IO_FILE *fp AND const char *filename AND 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:
+ 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, (_IO_off_t)0, _IO_seek_end, _IOS_INPUT|_IOS_OUTPUT)
+ == _IO_pos_BAD)
+ return NULL;
+ _IO_link_in(fp);
+ return fp;
+}
+
+_IO_FILE*
+DEFUN(_IO_file_attach, (fp, fd),
+ _IO_FILE *fp AND 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;
+ fp->_offset = _IO_pos_BAD;
+ return fp;
+}
+
+_IO_FILE*
+DEFUN(_IO_file_setbuf, (fp, p, len),
+ register _IO_FILE *fp AND char* p AND _IO_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;
+}
+
+/* Write TO_DO bytes from DATA to FP.
+ Then mark FP has having empty buffers. */
+
+int
+DEFUN(_IO_do_write, (fp, data, to_do),
+ register _IO_FILE *fp AND const char* data AND _IO_size_t to_do)
+{
+ _IO_size_t count;
+ if (to_do == 0)
+ return 0;
+ 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
+ is not needed nor desirable for Unix- or Posix-like systems.
+ Instead, just indicate that offset (before and after) is
+ unpredictable. */
+ fp->_offset = _IO_pos_BAD;
+ else if (fp->_IO_read_end != fp->_IO_write_base)
+ {
+ _IO_pos_t new_pos
+ = _IO_SYSSEEK(fp, fp->_IO_write_base - fp->_IO_read_end, 1);
+ if (new_pos == _IO_pos_BAD)
+ return EOF;
+ fp->_offset = new_pos;
+ }
+ count = _IO_SYSWRITE (fp, data, to_do);
+ if (fp->_cur_column)
+ fp->_cur_column = _IO_adjust_column(fp->_cur_column - 1, data, to_do) + 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 != to_do ? EOF : 0;
+}
+
+int
+DEFUN(_IO_file_underflow, (fp),
+ register _IO_FILE *fp)
+{
+ _IO_ssize_t count;
+#if 0
+ /* SysV does not make this test; take it out for compatibility */
+ if (fp->_flags & _IO_EOF_SEEN)
+ return (EOF);
+#endif
+
+ if (fp->_flags & _IO_NO_READS)
+ return EOF;
+ if (fp->_IO_read_ptr < fp->_IO_read_end)
+ return *(unsigned char*)fp->_IO_read_ptr;
+
+ if (fp->_IO_buf_base == NULL)
+ _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);
+
+ 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_base = fp->_IO_read_ptr = fp->_IO_buf_base;
+ fp->_IO_read_end = fp->_IO_buf_base + count;
+ fp->_IO_write_base = fp->_IO_write_ptr = fp->_IO_write_end
+ = fp->_IO_buf_base;
+ if (count == 0)
+ return EOF;
+ if (fp->_offset != _IO_pos_BAD)
+ _IO_pos_adjust(fp->_offset, count);
+ return *(unsigned char*)fp->_IO_read_ptr;
+}
+
+int
+DEFUN(_IO_file_overflow, (f, ch),
+ register _IO_FILE* f AND int ch)
+{
+ if (f->_flags & _IO_NO_WRITES) /* SET ERROR */
+ 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. */
+ 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_do_flush(f);
+ if (f->_IO_write_ptr == f->_IO_buf_end ) /* Buffer is really full */
+ if (_IO_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_do_flush(f) == EOF)
+ return EOF;
+ return (unsigned char)ch;
+}
+
+int
+DEFUN(_IO_file_sync, (fp),
+ register _IO_FILE* fp)
+{
+ _IO_size_t delta;
+ /* char* ptr = cur_ptr(); */
+ if (fp->_IO_write_ptr > fp->_IO_write_base)
+ if (_IO_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
+ _IO_off_t new_pos = _IO_SYSSEEK (fp, delta, 1);
+ if (new_pos != (_IO_off_t)EOF)
+ fp->_IO_read_end = fp->_IO_read_ptr;
+#ifdef ESPIPE
+ else if (errno == ESPIPE)
+ ; /* Ignore error from unseekable devices. */
+#endif
+ else
+ return EOF;
+ }
+ fp->_offset = _IO_pos_BAD;
+ /* FIXME: Cleanup - can this be shared? */
+ /* setg(base(), ptr, ptr); */
+ return 0;
+}
+
+_IO_pos_t
+DEFUN(_IO_file_seekoff, (fp, offset, dir, mode),
+ register _IO_FILE *fp AND _IO_off_t offset AND int dir AND int mode)
+{
+ _IO_pos_t result;
+ _IO_off_t delta, new_offset;
+ long count;
+
+ 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 ptr. 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-papped 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)
+ {
+ _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->_offset == _IO_pos_BAD)
+ goto dumb;
+ /* Make offset absolute, assuming current pointer is file_ptr(). */
+ offset += _IO_pos_as_off(fp->_offset);
+
+ dir = _IO_seek_set;
+ break;
+ case _IO_seek_set:
+ break;
+ case _IO_seek_end:
+ {
+ struct stat 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 destination is within current buffer, optimize: */
+ if (fp->_offset != _IO_pos_BAD && fp->_IO_read_base != NULL
+ && !_IO_in_backup (fp))
+ {
+ /* Offset relative to start of main get area. */
+ _IO_pos_t rel_offset = offset - fp->_offset
+ + (fp->_IO_read_end - fp->_IO_read_base);
+ if (rel_offset >= 0)
+ {
+#if 0
+ if (_IO_in_backup(fp))
+ _IO_switch_to_main_get_area(fp);
+#endif
+ 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);
+ return offset;
+ }
+#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;
+ return offset;
+ }
+#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);
+ return offset;
+ }
+#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,
+ 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->_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->_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;
+}
+
+_IO_ssize_t
+DEFUN(_IO_file_read, (fp, buf, size),
+ register _IO_FILE* fp AND void* buf AND _IO_ssize_t size)
+{
+ for (;;)
+ {
+ _IO_ssize_t count = _IO_read(fp->_fileno, buf, size);
+#ifdef EINTR
+ if (count == -1 && errno == EINTR)
+ continue;
+#endif
+ return count;
+ }
+}
+
+_IO_pos_t
+DEFUN(_IO_file_seek, (fp, offset, dir),
+ _IO_FILE *fp AND _IO_off_t offset AND int dir)
+{
+ return _IO_lseek(fp->_fileno, offset, dir);
+}
+
+int
+DEFUN(_IO_file_stat, (fp, st),
+ _IO_FILE *fp AND void* st)
+{
+ return _IO_fstat(fp->_fileno, (struct stat*)st);
+}
+
+int
+DEFUN(_IO_file_close, (fp),
+ _IO_FILE* fp)
+{
+ return _IO_close(fp->_fileno);
+}
+
+_IO_ssize_t
+DEFUN(_IO_file_write, (f, data, n),
+ register _IO_FILE* f AND const void* data AND _IO_ssize_t n)
+{
+ _IO_ssize_t to_do = n;
+ while (to_do > 0)
+ {
+ _IO_ssize_t count = _IO_write(f->_fileno, data, to_do);
+ if (count == EOF)
+ {
+#ifdef EINTR
+ if (errno == EINTR)
+ continue;
+ else
+#endif
+ {
+ f->_flags |= _IO_ERR_SEEN;
+ break;
+ }
+ }
+ to_do -= count;
+ data = (void*)((char*)data + count);
+ }
+ n -= to_do;
+ if (f->_offset >= 0)
+ f->_offset += n;
+ return n;
+}
+
+_IO_size_t
+DEFUN(_IO_file_xsputn, (f, data, n),
+ _IO_FILE *f AND const void *data AND _IO_size_t n)
+{
+ register const char *s = (char*) data;
+ _IO_size_t to_do = n;
+ int must_flush = 0;
+ _IO_size_t count;
+
+ 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. */
+ count = f->_IO_write_end - f->_IO_write_ptr; /* Space available. */
+ if ((f->_flags & _IO_LINE_BUF) && (f->_flags & _IO_CURRENTLY_PUTTING))
+ {
+ count = f->_IO_buf_end - f->_IO_write_ptr;
+ if (count >= n)
+ { register const char *p;
+ for (p = s + n; p > s; )
+ {
+ if (*--p == '\n') {
+ count = p - s + 1;
+ must_flush = 1;
+ break;
+ }
+ }
+ }
+ }
+ /* Then fill the buffer. */
+ if (count > 0)
+ {
+ if (count > to_do)
+ count = to_do;
+ if (count > 20) {
+ memcpy(f->_IO_write_ptr, s, count);
+ s += count;
+ }
+ else
+ {
+ register char *p = f->_IO_write_ptr;
+ register int i = (int)count;
+ while (--i >= 0) *p++ = *s++;
+ }
+ f->_IO_write_ptr += count;
+ to_do -= count;
+ }
+ if (to_do + must_flush > 0)
+ { _IO_size_t block_size, dont_write;
+ /* Next flush the (full) buffer. */
+ if (__overflow(f, EOF) == EOF)
+ return 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;
+ dont_write = block_size >= 128 ? to_do % block_size : 0;
+
+ count = to_do - dont_write;
+ if (_IO_do_write(f, s, count) == EOF)
+ return n - to_do;
+ to_do = dont_write;
+
+ /* 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 (dont_write)
+ to_do -= _IO_default_xsputn(f, s+count, dont_write);
+ }
+ return n - to_do;
+}
+
+#if 0
+/* Work in progress */
+_IO_size_t
+DEFUN(_IO_file_xsgetn, (fp, data, n),
+ _IO_FILE *fp AND void *data AND _IO_size_t n)
+{
+ register _IO_size_t more = n;
+ register char *s = data;
+ for (;;)
+ {
+ _IO_ssize_t count = fp->_IO_read_end - fp->_IO_read_ptr; /* Data available. */
+ if (count > 0)
+ {
+ if (count > more)
+ count = more;
+ if (count > 20)
+ {
+ memcpy(s, fp->_IO_read_ptr, count);
+ s += count;
+ fp->_IO_read_ptr += count;
+ }
+ else if (count <= 0)
+ count = 0;
+ else
+ {
+ register char *p = fp->_IO_read_ptr;
+ register int i = (int)count;
+ while (--i >= 0) *s++ = *p++;
+ fp->_IO_read_ptr = p;
+ }
+ more -= count;
+ }
+#if 0
+ if (! _IO_in put_mode (fp)
+ && ! _IO_have_markers (fp) && ! IO_have_backup (fp))
+ {
+ /* This is an optimization of _IO_file_underflow */
+ if (fp->_flags & _IO_NO_READS)
+ break;
+ /* If we're reading a lot of data, don't bother allocating
+ a buffer. But if we're only reading a bit, perhaps we should ??*/
+ if (count <= 512 && fp->_IO_buf_base == NULL)
+ _IO_doallocbuf(fp);
+ if (fp->_flags & (_IO_LINE_BUF|_IO_UNBUFFERED))
+ _IO_flush_all_linebuffered();
+
+ _IO_switch_to_get_mode(fp); ???;
+ count = _IO_SYSREAD (fp, s, more);
+ if (count <= 0)
+ {
+ if (count == 0)
+ fp->_flags |= _IO_EOF_SEEN;
+ else
+ fp->_flags |= _IO_ERR_SEEN, count = 0;
+ }
+
+ s += count;
+ more -= count;
+ }
+#endif
+ if (more == 0 || __underflow(fp) == EOF)
+ break;
+ }
+ return n - more;
+}
+#endif
+
+struct _IO_jump_t _IO_file_jumps = {
+ JUMP_INIT_DUMMY,
+ JUMP_INIT(finish, _IO_file_finish),
+ JUMP_INIT(overflow, _IO_file_overflow),
+ JUMP_INIT(underflow, _IO_file_underflow),
+ JUMP_INIT(uflow, _IO_default_uflow),
+ JUMP_INIT(pbackfail, _IO_default_pbackfail),
+ JUMP_INIT(xsputn, _IO_file_xsputn),
+ JUMP_INIT(xsgetn, _IO_default_xsgetn),
+ JUMP_INIT(seekoff, _IO_file_seekoff),
+ JUMP_INIT(seekpos, _IO_default_seekpos),
+ JUMP_INIT(setbuf, _IO_file_setbuf),
+ JUMP_INIT(sync, _IO_file_sync),
+ JUMP_INIT(doallocate, _IO_file_doallocate),
+ JUMP_INIT(read, _IO_file_read),
+ JUMP_INIT(write, _IO_file_write),
+ JUMP_INIT(seek, _IO_file_seek),
+ JUMP_INIT(close, _IO_file_close),
+ JUMP_INIT(stat, _IO_file_stat)
+};
generated by cgit v1.2.3 (git 2.39.1) at 2024-05-14 14:10:34 +0000