1 //===========================================================================
5 // C library stdio stream buffer functions
7 //===========================================================================
8 //####ECOSGPLCOPYRIGHTBEGIN####
9 // -------------------------------------------
10 // This file is part of eCos, the Embedded Configurable Operating System.
11 // Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
13 // eCos is free software; you can redistribute it and/or modify it under
14 // the terms of the GNU General Public License as published by the Free
15 // Software Foundation; either version 2 or (at your option) any later version.
17 // eCos is distributed in the hope that it will be useful, but WITHOUT ANY
18 // WARRANTY; without even the implied warranty of MERCHANTABILITY or
19 // FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
22 // You should have received a copy of the GNU General Public License along
23 // with eCos; if not, write to the Free Software Foundation, Inc.,
24 // 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
26 // As a special exception, if other files instantiate templates or use macros
27 // or inline functions from this file, or you compile this file and link it
28 // with other works to produce a work based on this file, this file does not
29 // by itself cause the resulting work to be covered by the GNU General Public
30 // License. However the source code for this file must still be made available
31 // in accordance with section (3) of the GNU General Public License.
33 // This exception does not invalidate any other reasons why a work based on
34 // this file might be covered by the GNU General Public License.
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37 // at http://sources.redhat.com/ecos/ecos-license/
38 // -------------------------------------------
39 //####ECOSGPLCOPYRIGHTEND####
40 //===========================================================================
41 //#####DESCRIPTIONBEGIN####
43 // Author(s): jlarmour
50 //####DESCRIPTIONEND####
52 //===========================================================================
56 #include <pkgconf/libc_stdio.h> // Configuration header
58 // Include buffered I/O?
59 #if defined(CYGSEM_LIBC_STDIO_WANT_BUFFERED_IO)
64 #include <cyg/infra/cyg_type.h> // Common project-wide type definitions
65 #include <cyg/infra/cyg_ass.h> // Assertion support
66 #include <errno.h> // Cyg_ErrNo
67 #include <stdlib.h> // malloc() and free()
68 #include <cyg/libc/stdio/streambuf.hxx> // header for this file, just in case
73 Cyg_StdioStreamBuffer::set_buffer( cyg_ucount32 size,
74 cyg_uint8 *new_buffer )
77 #ifdef CYGSEM_LIBC_STDIO_DYNAMIC_SETVBUF
79 // user-supplied buffer?
80 if (new_buffer != NULL) {
81 CYG_CHECK_DATA_PTR(new_buffer, "new_buffer not valid");
82 #ifdef CYGSEM_LIBC_STDIO_SETVBUF_MALLOC
83 // first check if we were responsible for the old buffer
89 buffer_bottom = new_buffer;
91 #ifdef CYGSEM_LIBC_STDIO_SETVBUF_MALLOC
92 else if ( size != buffer_size ) { // as long as its different from
94 cyg_uint8 *malloced_buf;
96 malloced_buf = (cyg_uint8 * )malloc( size );
97 if (malloced_buf == NULL)
100 // should the old buffer be freed? This waits till after we know
101 // whether the malloc succeeded
103 free( buffer_bottom );
105 buffer_bottom = malloced_buf;
111 // Here we have not been given a new buffer, but have been given
112 // a new buffer size. If possible, we just shrink what we already
114 else if( size > buffer_size )
118 #else // ifdef CYGSEM_LIBC_STDIO_DYNAMIC_SETVBUF
120 // In this config we can't use a different buffer, or set a
121 // size greater than now. We can pretend to shrink it though
123 // Note on the next line we compare it with the size of static_buffer
124 // and not the current size, as that's what is the limiting factor
125 if ( (new_buffer != NULL) || (size > sizeof(static_buffer)) )
128 #endif // ifdef CYGSEM_LIBC_STDIO_DYNAMIC_SETVBUF
130 buffer_top = current_buffer_position = &buffer_bottom[0];
138 #endif // if defined(CYGSEM_LIBC_STDIO_WANT_BUFFERED_IO)