| 1 | // reduce buffer size, avoiding mem copy |
| 2 | export function shrinkBuf (buf, size) { |
| 3 | if (buf.length === size) { return buf; } |
| 4 | if (buf.subarray) { return buf.subarray(0, size); } |
| 5 | buf.length = size; |
| 6 | return buf; |
| 7 | }; |
| 8 | |
| 9 | |
| 10 | export function arraySet (dest, src, src_offs, len, dest_offs) { |
| 11 | if (src.subarray && dest.subarray) { |
| 12 | dest.set(src.subarray(src_offs, src_offs + len), dest_offs); |
| 13 | return; |
| 14 | } |
| 15 | // Fallback to ordinary array |
| 16 | for (var i = 0; i < len; i++) { |
| 17 | dest[dest_offs + i] = src[src_offs + i]; |
| 18 | } |
| 19 | } |
| 20 | |
| 21 | // Join array of chunks to single array. |
| 22 | export function flattenChunks (chunks) { |
| 23 | var i, l, len, pos, chunk, result; |
| 24 | |
| 25 | // calculate data length |
| 26 | len = 0; |
| 27 | for (i = 0, l = chunks.length; i < l; i++) { |
| 28 | len += chunks[i].length; |
| 29 | } |
| 30 | |
| 31 | // join chunks |
| 32 | result = new Uint8Array(len); |
| 33 | pos = 0; |
| 34 | for (i = 0, l = chunks.length; i < l; i++) { |
| 35 | chunk = chunks[i]; |
| 36 | result.set(chunk, pos); |
| 37 | pos += chunk.length; |
| 38 | } |
| 39 | |
| 40 | return result; |
| 41 | } |
| 42 | |
| 43 | export var Buf8 = Uint8Array; |
| 44 | export var Buf16 = Uint16Array; |
| 45 | export var Buf32 = Int32Array; |