7 //#include "buffer_tree.h"
13 /** The number of references to this buffer. */
17 struct btr_buffer_reference {
18 struct btr_buffer *btrb;
20 /* Each buffer reference belongs to the buffer queue list of some buffer tree node. */
21 struct list_head node;
26 struct btr_node *parent;
27 /* The position of this btr node in the buffer tree. */
28 struct list_head node;
29 /* The children nodes of this btr node are linked together in a list. */
30 struct list_head children;
32 * The input queue is a list of references to btr buffers. Each item on
33 * the list represents an input buffer which has not been completely
34 * used by this btr node.
36 struct list_head input_queue;
39 #define FOR_EACH_TARGET_NODE(_tn, _btrn) list_for_each_entry((_tn), \
40 &((_btrn)->children), node)
42 #define FOR_EACH_BUFFER_REF(_br, _btrn) \
43 list_for_each_entry((_br), &(_btrn)->input_queue, node)
44 #define FOR_EACH_BUFFER_REF_SAFE(_br, _tmp, _btrn) \
45 list_for_each_entry_safe((_br), (_tmp), &(_btrn)->input_queue, node)
47 INIT_STDERR_LOGGING(0);
49 struct btr_node *btr_new_node(char *name, struct btr_node *parent)
51 struct btr_node *btrn = para_malloc(sizeof(*btrn));
53 btrn->name = para_strdup(name);
54 btrn->parent = parent;
56 list_add_tail(&btrn->node, &parent->children);
57 INIT_LIST_HEAD(&btrn->children);
58 INIT_LIST_HEAD(&btrn->input_queue);
62 static struct btr_buffer *new_btrb(char *buf, size_t size)
64 struct btr_buffer *btrb = para_malloc(sizeof(*btrb));
72 void btr_drop_buffer_reference(struct btr_buffer_reference *br)
74 struct btr_buffer *btrb = br->btrb;
79 if (btrb->refcount == 0) {
85 static void add_btrb_to_targets(struct btr_buffer *btrb, struct btr_node *btrn)
87 struct btr_node *tn; /* target node */
89 FOR_EACH_TARGET_NODE(tn, btrn) {
90 struct btr_buffer_reference *br = para_malloc(sizeof(*br));
93 list_add_tail(&br->node, &tn->input_queue);
98 void btr_add_output(char *buf, size_t size, struct btr_node *btrn)
100 struct btr_buffer *btrb;
102 btrb = new_btrb(buf, size);
103 add_btrb_to_targets(btrb, btrn);
106 void btr_pushdown_br(struct btr_buffer_reference *br, struct btr_node *btrn)
108 add_btrb_to_targets(br->btrb, btrn);
109 btr_drop_buffer_reference(br);
112 void btr_pushdown(struct btr_node *btrn)
114 struct btr_buffer_reference *br, *tmp;
116 FOR_EACH_BUFFER_REF_SAFE(br, tmp, btrn)
117 btr_pushdown_br(br, btrn);
120 bool btr_no_children(struct btr_node *btrn)
122 return list_empty(&btrn->children);
125 bool btr_no_parent(struct btr_node *btrn)
127 return !btrn->parent;
130 bool btr_inplace_ok(struct btr_node *btrn)
134 return list_is_singular(&btrn->parent->children);
137 struct btr_buffer_reference *btr_next_br(struct btr_node *btrn)
139 if (list_empty(&btrn->input_queue))
141 return list_first_entry(&btrn->input_queue, struct btr_buffer_reference, node);
144 static inline size_t br_available_bytes(struct btr_buffer_reference *br)
146 return br->btrb->size - br->consumed;
149 size_t btr_get_buffer_by_reference(struct btr_buffer_reference *br, char **buf)
151 *buf = br->btrb->buf + br->consumed;
152 return br_available_bytes(br);
155 void btr_increase_used_bytes(struct btr_buffer_reference *br, size_t consumed)
157 br->consumed += consumed;
158 if (br->consumed == br->btrb->size)
159 btr_drop_buffer_reference(br);
162 static void flush_input_queue(struct btr_node *btrn)
164 struct btr_buffer_reference *br, *tmp;
165 FOR_EACH_BUFFER_REF_SAFE(br, tmp, btrn)
166 btr_drop_buffer_reference(br);
169 void btr_del_node(struct btr_node *btrn)
173 FOR_EACH_TARGET_NODE(tn, btrn)
175 flush_input_queue(btrn);
177 list_del(&btrn->node);
182 size_t btr_get_input_queue_size(struct btr_node *btrn)
184 struct btr_buffer_reference *br;
187 FOR_EACH_BUFFER_REF(br, btrn)
188 size += br_available_bytes(br);