2 * Copyright (c) 1995, Index Data
3 * See the file LICENSE for details.
4 * Sebastian Hammer, Adam Dickmeiss
7 * Revision 1.7 1995-09-27 15:02:59 quinn
8 * Modified function heads & prototypes.
10 * Revision 1.6 1995/08/21 09:10:41 quinn
11 * Smallish fixes to suppport new formats.
13 * Revision 1.5 1995/05/16 08:50:55 quinn
14 * License, documentation, and memory fixes
16 * Revision 1.4 1995/05/15 11:56:09 quinn
17 * More work on memory management.
19 * Revision 1.3 1995/04/18 08:15:21 quinn
20 * Added dynamic memory allocation on encoding (whew). Code is now somewhat
21 * neater. We'll make the same change for decoding one day.
23 * Revision 1.2 1995/03/17 10:17:52 quinn
24 * Added memory management.
26 * Revision 1.1 1995/03/14 10:27:40 quinn
27 * Modified makefile to use common lib
28 * Beginning to add memory management to odr
36 /* ------------------------ NIBBLE MEMORY ---------------------- */
38 #define ODR_MEM_CHUNK (10*1024)
40 typedef struct odr_memblock
46 struct odr_memblock *next;
49 static odr_memblock *freelist = 0; /* global freelist */
51 static void free_block(odr_memblock *p)
58 * acquire a block with a minimum of size free bytes.
60 static odr_memblock *get_block(int size)
64 for (r = freelist, l = 0; r; l = r, r = r->next)
74 int get = ODR_MEM_CHUNK;
78 if (!(r = malloc(sizeof(*r))))
80 if (!(r->buf = malloc(r->size = get)))
89 * Return p to the global freelist.
91 void MDF odr_release_mem(ODR_MEM p)
104 * Extract the memory control block from o.
106 ODR_MEM MDF odr_extract_mem(ODR o)
114 void MDF *odr_malloc(ODR o, int size)
116 struct odr_memblock *p = o->mem;
119 if (!p || p->size - p->top < size)
120 if (!(p = get_block(size)))
125 p->total = o->mem->total;
131 p->top += (size + (sizeof(long) - 1)) & ~(sizeof(long) - 1);
136 int MDF odr_total(ODR o)
138 return o->mem ? o->mem->total : 0;
141 /* ---------- memory management for data encoding ----------*/
144 int MDF odr_grow_block(odr_ecblock *b, int min_bytes)
154 if (togrow < min_bytes)
156 if (b->size && !(b->buf = realloc(b->buf, b->size += togrow)))
158 else if (!b->size && !(b->buf = malloc(b->size = togrow)))
161 fprintf(stderr, "New size for encode_buffer: %d\n", b->size);
166 int MDF odr_write(ODR o, unsigned char *buf, int bytes)
168 if (o->ecb.pos + bytes >= o->ecb.size && odr_grow_block(&o->ecb, bytes))
173 memcpy(o->ecb.buf + o->ecb.pos, buf, bytes);
175 if (o->ecb.pos > o->ecb.top)
176 o->ecb.top = o->ecb.pos;
180 int MDF odr_seek(ODR o, int whence, int offset)
182 if (whence == ODR_S_CUR)
183 offset += o->ecb.pos;
184 else if (whence == ODR_S_END)
185 offset += o->ecb.top;
186 if (offset > o->ecb.size && odr_grow_block(&o->ecb, offset - o->ecb.size))