2 * Copyright (c) 1995, Index Data
3 * See the file LICENSE for details.
4 * Sebastian Hammer, Adam Dickmeiss
7 * Revision 1.6 1995-08-21 09:10:41 quinn
8 * Smallish fixes to suppport new formats.
10 * Revision 1.5 1995/05/16 08:50:55 quinn
11 * License, documentation, and memory fixes
13 * Revision 1.4 1995/05/15 11:56:09 quinn
14 * More work on memory management.
16 * Revision 1.3 1995/04/18 08:15:21 quinn
17 * Added dynamic memory allocation on encoding (whew). Code is now somewhat
18 * neater. We'll make the same change for decoding one day.
20 * Revision 1.2 1995/03/17 10:17:52 quinn
21 * Added memory management.
23 * Revision 1.1 1995/03/14 10:27:40 quinn
24 * Modified makefile to use common lib
25 * Beginning to add memory management to odr
33 /* ------------------------ NIBBLE MEMORY ---------------------- */
35 #define ODR_MEM_CHUNK (10*1024)
37 typedef struct odr_memblock
43 struct odr_memblock *next;
46 static odr_memblock *freelist = 0; /* global freelist */
48 static void free_block(odr_memblock *p)
55 * acquire a block with a minimum of size free bytes.
57 static odr_memblock *get_block(int size)
61 for (r = freelist, l = 0; r; l = r, r = r->next)
71 int get = ODR_MEM_CHUNK;
75 if (!(r = malloc(sizeof(*r))))
77 if (!(r->buf = malloc(r->size = get)))
86 * Return p to the global freelist.
88 void odr_release_mem(ODR_MEM p)
101 * Extract the memory control block from o.
103 ODR_MEM odr_extract_mem(ODR o)
111 void *odr_malloc(ODR o, int size)
113 struct odr_memblock *p = o->mem;
116 if (!p || p->size - p->top < size)
117 if (!(p = get_block(size)))
122 p->total = o->mem->total;
128 p->top += (size + (sizeof(long) - 1)) & ~(sizeof(long) - 1);
135 return o->mem ? o->mem->total : 0;
138 /* ---------- memory management for data encoding ----------*/
141 int odr_grow_block(odr_ecblock *b, int min_bytes)
151 if (togrow < min_bytes)
153 if (b->size && !(b->buf = realloc(b->buf, b->size += togrow)))
155 else if (!b->size && !(b->buf = malloc(b->size = togrow)))
158 fprintf(stderr, "New size for encode_buffer: %d\n", b->size);
163 int odr_write(ODR o, unsigned char *buf, int bytes)
165 if (o->ecb.pos + bytes >= o->ecb.size && odr_grow_block(&o->ecb, bytes))
170 memcpy(o->ecb.buf + o->ecb.pos, buf, bytes);
172 if (o->ecb.pos > o->ecb.top)
173 o->ecb.top = o->ecb.pos;
177 int odr_seek(ODR o, int whence, int offset)
179 if (whence == ODR_S_CUR)
180 offset += o->ecb.pos;
181 else if (whence == ODR_S_END)
182 offset += o->ecb.top;
183 if (offset > o->ecb.size && odr_grow_block(&o->ecb, offset - o->ecb.size))