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Diffstat (limited to 'alarm/node_modules/pako/lib/utils/strings.js')
-rw-r--r-- | alarm/node_modules/pako/lib/utils/strings.js | 187 |
1 files changed, 0 insertions, 187 deletions
diff --git a/alarm/node_modules/pako/lib/utils/strings.js b/alarm/node_modules/pako/lib/utils/strings.js deleted file mode 100644 index b07a732..0000000 --- a/alarm/node_modules/pako/lib/utils/strings.js +++ /dev/null @@ -1,187 +0,0 @@ -// String encode/decode helpers -'use strict'; - - -var utils = require('./common'); - - -// Quick check if we can use fast array to bin string conversion -// -// - apply(Array) can fail on Android 2.2 -// - apply(Uint8Array) can fail on iOS 5.1 Safari -// -var STR_APPLY_OK = true; -var STR_APPLY_UIA_OK = true; - -try { String.fromCharCode.apply(null, [ 0 ]); } catch (__) { STR_APPLY_OK = false; } -try { String.fromCharCode.apply(null, new Uint8Array(1)); } catch (__) { STR_APPLY_UIA_OK = false; } - - -// Table with utf8 lengths (calculated by first byte of sequence) -// Note, that 5 & 6-byte values and some 4-byte values can not be represented in JS, -// because max possible codepoint is 0x10ffff -var _utf8len = new utils.Buf8(256); -for (var q = 0; q < 256; q++) { - _utf8len[q] = (q >= 252 ? 6 : q >= 248 ? 5 : q >= 240 ? 4 : q >= 224 ? 3 : q >= 192 ? 2 : 1); -} -_utf8len[254] = _utf8len[254] = 1; // Invalid sequence start - - -// convert string to array (typed, when possible) -exports.string2buf = function (str) { - var buf, c, c2, m_pos, i, str_len = str.length, buf_len = 0; - - // count binary size - for (m_pos = 0; m_pos < str_len; m_pos++) { - c = str.charCodeAt(m_pos); - if ((c & 0xfc00) === 0xd800 && (m_pos + 1 < str_len)) { - c2 = str.charCodeAt(m_pos + 1); - if ((c2 & 0xfc00) === 0xdc00) { - c = 0x10000 + ((c - 0xd800) << 10) + (c2 - 0xdc00); - m_pos++; - } - } - buf_len += c < 0x80 ? 1 : c < 0x800 ? 2 : c < 0x10000 ? 3 : 4; - } - - // allocate buffer - buf = new utils.Buf8(buf_len); - - // convert - for (i = 0, m_pos = 0; i < buf_len; m_pos++) { - c = str.charCodeAt(m_pos); - if ((c & 0xfc00) === 0xd800 && (m_pos + 1 < str_len)) { - c2 = str.charCodeAt(m_pos + 1); - if ((c2 & 0xfc00) === 0xdc00) { - c = 0x10000 + ((c - 0xd800) << 10) + (c2 - 0xdc00); - m_pos++; - } - } - if (c < 0x80) { - /* one byte */ - buf[i++] = c; - } else if (c < 0x800) { - /* two bytes */ - buf[i++] = 0xC0 | (c >>> 6); - buf[i++] = 0x80 | (c & 0x3f); - } else if (c < 0x10000) { - /* three bytes */ - buf[i++] = 0xE0 | (c >>> 12); - buf[i++] = 0x80 | (c >>> 6 & 0x3f); - buf[i++] = 0x80 | (c & 0x3f); - } else { - /* four bytes */ - buf[i++] = 0xf0 | (c >>> 18); - buf[i++] = 0x80 | (c >>> 12 & 0x3f); - buf[i++] = 0x80 | (c >>> 6 & 0x3f); - buf[i++] = 0x80 | (c & 0x3f); - } - } - - return buf; -}; - -// Helper (used in 2 places) -function buf2binstring(buf, len) { - // On Chrome, the arguments in a function call that are allowed is `65534`. - // If the length of the buffer is smaller than that, we can use this optimization, - // otherwise we will take a slower path. - if (len < 65534) { - if ((buf.subarray && STR_APPLY_UIA_OK) || (!buf.subarray && STR_APPLY_OK)) { - return String.fromCharCode.apply(null, utils.shrinkBuf(buf, len)); - } - } - - var result = ''; - for (var i = 0; i < len; i++) { - result += String.fromCharCode(buf[i]); - } - return result; -} - - -// Convert byte array to binary string -exports.buf2binstring = function (buf) { - return buf2binstring(buf, buf.length); -}; - - -// Convert binary string (typed, when possible) -exports.binstring2buf = function (str) { - var buf = new utils.Buf8(str.length); - for (var i = 0, len = buf.length; i < len; i++) { - buf[i] = str.charCodeAt(i); - } - return buf; -}; - - -// convert array to string -exports.buf2string = function (buf, max) { - var i, out, c, c_len; - var len = max || buf.length; - - // Reserve max possible length (2 words per char) - // NB: by unknown reasons, Array is significantly faster for - // String.fromCharCode.apply than Uint16Array. - var utf16buf = new Array(len * 2); - - for (out = 0, i = 0; i < len;) { - c = buf[i++]; - // quick process ascii - if (c < 0x80) { utf16buf[out++] = c; continue; } - - c_len = _utf8len[c]; - // skip 5 & 6 byte codes - if (c_len > 4) { utf16buf[out++] = 0xfffd; i += c_len - 1; continue; } - - // apply mask on first byte - c &= c_len === 2 ? 0x1f : c_len === 3 ? 0x0f : 0x07; - // join the rest - while (c_len > 1 && i < len) { - c = (c << 6) | (buf[i++] & 0x3f); - c_len--; - } - - // terminated by end of string? - if (c_len > 1) { utf16buf[out++] = 0xfffd; continue; } - - if (c < 0x10000) { - utf16buf[out++] = c; - } else { - c -= 0x10000; - utf16buf[out++] = 0xd800 | ((c >> 10) & 0x3ff); - utf16buf[out++] = 0xdc00 | (c & 0x3ff); - } - } - - return buf2binstring(utf16buf, out); -}; - - -// Calculate max possible position in utf8 buffer, -// that will not break sequence. If that's not possible -// - (very small limits) return max size as is. -// -// buf[] - utf8 bytes array -// max - length limit (mandatory); -exports.utf8border = function (buf, max) { - var pos; - - max = max || buf.length; - if (max > buf.length) { max = buf.length; } - - // go back from last position, until start of sequence found - pos = max - 1; - while (pos >= 0 && (buf[pos] & 0xC0) === 0x80) { pos--; } - - // Very small and broken sequence, - // return max, because we should return something anyway. - if (pos < 0) { return max; } - - // If we came to start of buffer - that means buffer is too small, - // return max too. - if (pos === 0) { return max; } - - return (pos + _utf8len[buf[pos]] > max) ? pos : max; -}; |