/* FILE * interface to a struct __printf_buffer. Multibyte version.
Copyright (C) 2022 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
/* Commit the data directly written through the stdio stream. */
static void
__printf_buffer_as_file_commit (struct __printf_buffer_as_file *file)
{
/* Check that the write pointers in the file stream are consistent
with the next buffer. */
assert (file->stream._IO_write_ptr >= file->next->write_ptr);
assert (file->stream._IO_write_ptr <= file->next->write_end);
assert (file->stream._IO_write_base == file->next->write_base);
assert (file->stream._IO_write_end == file->next->write_end);
file->next->write_ptr = file->stream._IO_write_ptr;
}
/* Pointer the FILE * write buffer into the active printf_buffer
area. */
static void
__printf_buffer_as_file_switch_to_buffer (struct __printf_buffer_as_file *file)
{
file->stream._IO_write_base = file->next->write_base;
file->stream._IO_write_ptr = file->next->write_ptr;
file->stream._IO_write_end = file->next->write_end;
}
/* Only a small subset of the vtable functions is implemented here,
following _IO_obstack_jumps. */
static int
__printf_buffer_as_file_overflow (FILE *fp, int ch)
{
struct __printf_buffer_as_file *file = (struct __printf_buffer_as_file *) fp;
__printf_buffer_as_file_commit (file);
/* EOF means only a flush is requested. */
if (ch != EOF)
__printf_buffer_putc (file->next, ch);
/* Ensure that flushing actually produces room. */
if (!__printf_buffer_has_failed (file->next)
&& file->next->write_ptr == file->next->write_end)
__printf_buffer_flush (file->next);
__printf_buffer_as_file_switch_to_buffer (file);
if (!__printf_buffer_has_failed (file->next))
return (unsigned char) ch;
else
return EOF;
}
static size_t
__printf_buffer_as_file_xsputn (FILE *fp, const void *buf, size_t len)
{
struct __printf_buffer_as_file *file = (struct __printf_buffer_as_file *) fp;
__printf_buffer_as_file_commit (file);
/* Copy the data. */
__printf_buffer_write (file->next, buf, len);
__printf_buffer_as_file_switch_to_buffer (file);
if (!__printf_buffer_has_failed (file->next))
return len;
else
/* We may actually have written something. But the stream is
corrupted in this case anyway, so try not to divine the write
count here. */
return 0;
}
static const struct _IO_jump_t _IO_printf_buffer_as_file_jumps libio_vtable =
{
JUMP_INIT_DUMMY,
JUMP_INIT(finish, NULL),
JUMP_INIT(overflow, __printf_buffer_as_file_overflow),
JUMP_INIT(underflow, NULL),
JUMP_INIT(uflow, NULL),
JUMP_INIT(pbackfail, NULL),
JUMP_INIT(xsputn, __printf_buffer_as_file_xsputn),
JUMP_INIT(xsgetn, NULL),
JUMP_INIT(seekoff, NULL),
JUMP_INIT(seekpos, NULL),
JUMP_INIT(setbuf, NULL),
JUMP_INIT(sync, NULL),
JUMP_INIT(doallocate, NULL),
JUMP_INIT(read, NULL),
JUMP_INIT(write, NULL),
JUMP_INIT(seek, NULL),
JUMP_INIT(close, NULL),
JUMP_INIT(stat, NULL),
JUMP_INIT(showmanyc, NULL),
JUMP_INIT(imbue, NULL)
};
void
__printf_buffer_as_file_init (struct __printf_buffer_as_file *file,
struct __printf_buffer *next)
{
file->stream._lock = NULL;
_IO_no_init (&file->stream, _IO_USER_LOCK, -1, NULL, NULL);
file->vtable = &_IO_printf_buffer_as_file_jumps;
/* Set up the write buffer from the next buffer. */
file->next = next;
__printf_buffer_as_file_switch_to_buffer (file);
/* Mark the read area as inactive, by making all pointers equal. */
file->stream._IO_read_base = file->stream._IO_write_base;
file->stream._IO_read_ptr = file->stream._IO_write_base;
file->stream._IO_read_end = file->stream._IO_write_base;
}
bool
__printf_buffer_as_file_terminate (struct __printf_buffer_as_file *file)
{
if (file->stream._flags & _IO_ERR_SEEN)
return false;
else
{
__printf_buffer_as_file_commit (file);
return true;
}
}