1 /* $Id$
2
3 Part of SWI-Prolog
4
5 Author: Jan Wielemaker
6 E-mail: jan@swi.psy.uva.nl
7 WWW: http://www.swi-prolog.org
8 Copyright (C): 1985-2002, University of Amsterdam
9
10 This library is free software; you can redistribute it and/or
11 modify it under the terms of the GNU Lesser General Public
12 License as published by the Free Software Foundation; either
13 version 2.1 of the License, or (at your option) any later version.
14
15 This library is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
18 Lesser General Public License for more details.
19
20 You should have received a copy of the GNU Lesser General Public
21 License along with this library; if not, write to the Free Software
22 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 */
24
25 #include "pl-incl.h"
26
27 // vsc: changed from SWI
28 #define discardable_buffer (LD->discardable_buffer)
29 #define buffer_ring (LD->buffer_ring)
30 #define current_buffer_id (LD->current_buffer_id)
31
32 Buffer
findBuffer(int flags)33 findBuffer(int flags)
34 { GET_LD
35 Buffer b;
36
37 if ( flags & BUF_RING )
38 { if ( ++current_buffer_id == BUFFER_RING_SIZE )
39 current_buffer_id = 0;
40 b = &buffer_ring[current_buffer_id];
41 } else
42 b = &discardable_buffer;
43
44 if ( !b->base )
45 initBuffer(b);
46
47 emptyBuffer(b);
48 return b;
49 }
50
51 int
unfindBuffer(int flags)52 unfindBuffer(int flags)
53 { GET_LD
54 if ( flags & BUF_RING )
55 { if ( --current_buffer_id <= 0 )
56 current_buffer_id = BUFFER_RING_SIZE-1;
57 }
58
59 fail;
60 }
61
62
63
64 void
growBuffer(Buffer b,size_t minfree)65 growBuffer(Buffer b, size_t minfree)
66 { size_t osz = b->max - b->base, sz = osz;
67 size_t top = b->top - b->base;
68
69 if ( b->max - b->top >= (int)minfree )
70 return;
71
72 if ( sz < 512 )
73 sz = 512; /* minimum reasonable size */
74 while( top + minfree > sz )
75 sz *= 2;
76
77 if ( b->base != b->static_buffer )
78 {
79 #ifdef BUFFER_USES_MALLOC
80 b->base = realloc(b->base, sz);
81 if ( !b->base )
82 outOfCore();
83 #else
84 char *old = b->base;
85 b->base = allocHeap(sz);
86 memcpy(b->base, old, osz);
87 #endif
88 } else /* from static buffer */
89 { char *new;
90 #ifdef BUFFER_USES_MALLOC
91 if ( !(new = malloc(sz)) )
92 outOfCore();
93 #else
94 new = allocHeap(sz);
95 #endif
96 memcpy(new, b->static_buffer, osz);
97 b->base = new;
98 }
99
100 b->top = b->base + top;
101 b->max = b->base + sz;
102 }
103
104 char *
buffer_string(const char * s,int flags)105 buffer_string(const char *s, int flags)
106 { Buffer b = findBuffer(flags);
107 size_t l = strlen(s) + 1;
108
109 addMultipleBuffer(b, s, l, char);
110
111 return baseBuffer(b, char);
112 }
113
114
115