usb/line6/midibuf.c

33 static int midibuf_is_empty(struct midi_buffer *this)
35 	return (this->pos_read == this->pos_write) && !this->full;
38 static int midibuf_is_full(struct midi_buffer *this)
40 	return this->full;
43 void line6_midibuf_reset(struct midi_buffer *this)
45 	this->pos_read = this->pos_write = this->full = 0;
46 	this->command_prev = -1;
49 int line6_midibuf_init(struct midi_buffer *this, int size, int split)
51 	this->buf = kmalloc(size, GFP_KERNEL);
53 	if (this->buf == NULL)
56 	this->size = size;
57 	this->split = split;
58 	line6_midibuf_reset(this);
62 int line6_midibuf_bytes_free(struct midi_buffer *this)
65 	    midibuf_is_full(this) ?
67 	    (this->pos_read - this->pos_write + this->size - 1) % this->size +
71 int line6_midibuf_bytes_used(struct midi_buffer *this)
74 	    midibuf_is_empty(this) ?
76 	    (this->pos_write - this->pos_read + this->size - 1) % this->size +
80 int line6_midibuf_write(struct midi_buffer *this, unsigned char *data,
87 	if (midibuf_is_full(this) || (length <= 0))
96 	bytes_free = line6_midibuf_bytes_free(this);
102 		length1 = this->size - this->pos_write;
106 			memcpy(this->buf + this->pos_write, data, length);
107 			this->pos_write += length;
111 			memcpy(this->buf + this->pos_write, data, length1);
112 			memcpy(this->buf, data + length1, length2);
113 			this->pos_write = length2;
116 		if (this->pos_write == this->pos_read)
117 			this->full = 1;
123 int line6_midibuf_read(struct midi_buffer *this, unsigned char *data,
137 	if (midibuf_is_empty(this))
140 	bytes_used = line6_midibuf_bytes_used(this);
145 	length1 = this->size - this->pos_read;
147 	command = this->buf[this->pos_read];
157 			this->buf[this->pos_read] = fixed;
165 		this->command_prev = command;
167 		if (this->command_prev > 0) {
169 			    midibuf_message_length(this->command_prev);
185 				if (this->buf[this->pos_read + i] & 0x80)
194 				if (this->buf[this->pos_read + i] & 0x80)
201 					if (this->buf[i] & 0x80)
213 		if (!this->split)
224 		memcpy(data + repeat, this->buf + this->pos_read, length);
225 		this->pos_read += length;
229 		memcpy(data + repeat, this->buf + this->pos_read, length1);
230 		memcpy(data + repeat + length1, this->buf, length2);
231 		this->pos_read = length2;
235 		data[0] = this->command_prev;
237 	this->full = 0;
241 int line6_midibuf_ignore(struct midi_buffer *this, int length)
243 	int bytes_used = line6_midibuf_bytes_used(this);
248 	this->pos_read = (this->pos_read + length) % this->size;
249 	this->full = 0;
253 void line6_midibuf_destroy(struct midi_buffer *this)
255 	kfree(this->buf);
256 	this->buf = NULL;