gitweb / gitweb.json commit Teach rebase the --no-ff option. (b499549)
   1// Copyright (C) 2007, Fredrik Kuivinen <frekui@gmail.com>
   2//               2007, Petr Baudis <pasky@suse.cz>
   3//          2008-2009, Jakub Narebski <jnareb@gmail.com>
   4
   5/**
   6 * @fileOverview JavaScript code for gitweb (git web interface).
   7 * @license GPLv2 or later
   8 */
   9
  10/* ============================================================ */
  11/* functions for generic gitweb actions and views */
  12
  13/**
  14 * used to check if link has 'js' query parameter already (at end),
  15 * and other reasons to not add 'js=1' param at the end of link
  16 * @constant
  17 */
  18var jsExceptionsRe = /[;?]js=[01]$/;
  19
  20/**
  21 * Add '?js=1' or ';js=1' to the end of every link in the document
  22 * that doesn't have 'js' query parameter set already.
  23 *
  24 * Links with 'js=1' lead to JavaScript version of given action, if it
  25 * exists (currently there is only 'blame_incremental' for 'blame')
  26 *
  27 * @globals jsExceptionsRe
  28 */
  29function fixLinks() {
  30        var allLinks = document.getElementsByTagName("a") || document.links;
  31        for (var i = 0, len = allLinks.length; i < len; i++) {
  32                var link = allLinks[i];
  33                if (!jsExceptionsRe.test(link)) { // =~ /[;?]js=[01]$/;
  34                        link.href +=
  35                                (link.href.indexOf('?') === -1 ? '?' : ';') + 'js=1';
  36                }
  37        }
  38}
  39
  40
  41/* ============================================================ */
  42
  43/*
  44 * This code uses DOM methods instead of (nonstandard) innerHTML
  45 * to modify page.
  46 *
  47 * innerHTML is non-standard IE extension, though supported by most
  48 * browsers; however Firefox up to version 1.5 didn't implement it in
  49 * a strict mode (application/xml+xhtml mimetype).
  50 *
  51 * Also my simple benchmarks show that using elem.firstChild.data =
  52 * 'content' is slightly faster than elem.innerHTML = 'content'.  It
  53 * is however more fragile (text element fragment must exists), and
  54 * less feature-rich (we cannot add HTML).
  55 *
  56 * Note that DOM 2 HTML is preferred over generic DOM 2 Core; the
  57 * equivalent using DOM 2 Core is usually shown in comments.
  58 */
  59
  60
  61/* ============================================================ */
  62/* generic utility functions */
  63
  64
  65/**
  66 * pad number N with nonbreakable spaces on the left, to WIDTH characters
  67 * example: padLeftStr(12, 3, '\u00A0') == '\u00A012'
  68 *          ('\u00A0' is nonbreakable space)
  69 *
  70 * @param {Number|String} input: number to pad
  71 * @param {Number} width: visible width of output
  72 * @param {String} str: string to prefix to string, e.g. '\u00A0'
  73 * @returns {String} INPUT prefixed with (WIDTH - INPUT.length) x STR
  74 */
  75function padLeftStr(input, width, str) {
  76        var prefix = '';
  77
  78        width -= input.toString().length;
  79        while (width > 0) {
  80                prefix += str;
  81                width--;
  82        }
  83        return prefix + input;
  84}
  85
  86/**
  87 * Pad INPUT on the left to SIZE width, using given padding character CH,
  88 * for example padLeft('a', 3, '_') is '__a'.
  89 *
  90 * @param {String} input: input value converted to string.
  91 * @param {Number} width: desired length of output.
  92 * @param {String} ch: single character to prefix to string.
  93 *
  94 * @returns {String} Modified string, at least SIZE length.
  95 */
  96function padLeft(input, width, ch) {
  97        var s = input + "";
  98        while (s.length < width) {
  99                s = ch + s;
 100        }
 101        return s;
 102}
 103
 104/**
 105 * Create XMLHttpRequest object in cross-browser way
 106 * @returns XMLHttpRequest object, or null
 107 */
 108function createRequestObject() {
 109        try {
 110                return new XMLHttpRequest();
 111        } catch (e) {}
 112        try {
 113                return window.createRequest();
 114        } catch (e) {}
 115        try {
 116                return new ActiveXObject("Msxml2.XMLHTTP");
 117        } catch (e) {}
 118        try {
 119                return new ActiveXObject("Microsoft.XMLHTTP");
 120        } catch (e) {}
 121
 122        return null;
 123}
 124
 125
 126/* ============================================================ */
 127/* utility/helper functions (and variables) */
 128
 129var xhr;        // XMLHttpRequest object
 130var projectUrl; // partial query + separator ('?' or ';')
 131
 132// 'commits' is an associative map. It maps SHA1s to Commit objects.
 133var commits = {};
 134
 135/**
 136 * constructor for Commit objects, used in 'blame'
 137 * @class Represents a blamed commit
 138 * @param {String} sha1: SHA-1 identifier of a commit
 139 */
 140function Commit(sha1) {
 141        if (this instanceof Commit) {
 142                this.sha1 = sha1;
 143                this.nprevious = 0; /* number of 'previous', effective parents */
 144        } else {
 145                return new Commit(sha1);
 146        }
 147}
 148
 149/* ............................................................ */
 150/* progress info, timing, error reporting */
 151
 152var blamedLines = 0;
 153var totalLines  = '???';
 154var div_progress_bar;
 155var div_progress_info;
 156
 157/**
 158 * Detects how many lines does a blamed file have,
 159 * This information is used in progress info
 160 *
 161 * @returns {Number|String} Number of lines in file, or string '...'
 162 */
 163function countLines() {
 164        var table =
 165                document.getElementById('blame_table') ||
 166                document.getElementsByTagName('table')[0];
 167
 168        if (table) {
 169                return table.getElementsByTagName('tr').length - 1; // for header
 170        } else {
 171                return '...';
 172        }
 173}
 174
 175/**
 176 * update progress info and length (width) of progress bar
 177 *
 178 * @globals div_progress_info, div_progress_bar, blamedLines, totalLines
 179 */
 180function updateProgressInfo() {
 181        if (!div_progress_info) {
 182                div_progress_info = document.getElementById('progress_info');
 183        }
 184        if (!div_progress_bar) {
 185                div_progress_bar = document.getElementById('progress_bar');
 186        }
 187        if (!div_progress_info && !div_progress_bar) {
 188                return;
 189        }
 190
 191        var percentage = Math.floor(100.0*blamedLines/totalLines);
 192
 193        if (div_progress_info) {
 194                div_progress_info.firstChild.data  = blamedLines + ' / ' + totalLines +
 195                        ' (' + padLeftStr(percentage, 3, '\u00A0') + '%)';
 196        }
 197
 198        if (div_progress_bar) {
 199                //div_progress_bar.setAttribute('style', 'width: '+percentage+'%;');
 200                div_progress_bar.style.width = percentage + '%';
 201        }
 202}
 203
 204
 205var t_interval_server = '';
 206var cmds_server = '';
 207var t0 = new Date();
 208
 209/**
 210 * write how much it took to generate data, and to run script
 211 *
 212 * @globals t0, t_interval_server, cmds_server
 213 */
 214function writeTimeInterval() {
 215        var info_time = document.getElementById('generating_time');
 216        if (!info_time || !t_interval_server) {
 217                return;
 218        }
 219        var t1 = new Date();
 220        info_time.firstChild.data += ' + (' +
 221                t_interval_server + ' sec server blame_data / ' +
 222                (t1.getTime() - t0.getTime())/1000 + ' sec client JavaScript)';
 223
 224        var info_cmds = document.getElementById('generating_cmd');
 225        if (!info_time || !cmds_server) {
 226                return;
 227        }
 228        info_cmds.firstChild.data += ' + ' + cmds_server;
 229}
 230
 231/**
 232 * show an error message alert to user within page (in prohress info area)
 233 * @param {String} str: plain text error message (no HTML)
 234 *
 235 * @globals div_progress_info
 236 */
 237function errorInfo(str) {
 238        if (!div_progress_info) {
 239                div_progress_info = document.getElementById('progress_info');
 240        }
 241        if (div_progress_info) {
 242                div_progress_info.className = 'error';
 243                div_progress_info.firstChild.data = str;
 244        }
 245}
 246
 247/* ............................................................ */
 248/* coloring rows during blame_data (git blame --incremental) run */
 249
 250/**
 251 * used to extract N from 'colorN', where N is a number,
 252 * @constant
 253 */
 254var colorRe = /\bcolor([0-9]*)\b/;
 255
 256/**
 257 * return N if <tr class="colorN">, otherwise return null
 258 * (some browsers require CSS class names to begin with letter)
 259 *
 260 * @param {HTMLElement} tr: table row element to check
 261 * @param {String} tr.className: 'class' attribute of tr element
 262 * @returns {Number|null} N if tr.className == 'colorN', otherwise null
 263 *
 264 * @globals colorRe
 265 */
 266function getColorNo(tr) {
 267        if (!tr) {
 268                return null;
 269        }
 270        var className = tr.className;
 271        if (className) {
 272                var match = colorRe.exec(className);
 273                if (match) {
 274                        return parseInt(match[1], 10);
 275                }
 276        }
 277        return null;
 278}
 279
 280var colorsFreq = [0, 0, 0];
 281/**
 282 * return one of given possible colors (curently least used one)
 283 * example: chooseColorNoFrom(2, 3) returns 2 or 3
 284 *
 285 * @param {Number[]} arguments: one or more numbers
 286 *        assumes that  1 <= arguments[i] <= colorsFreq.length
 287 * @returns {Number} Least used color number from arguments
 288 * @globals colorsFreq
 289 */
 290function chooseColorNoFrom() {
 291        // choose the color which is least used
 292        var colorNo = arguments[0];
 293        for (var i = 1; i < arguments.length; i++) {
 294                if (colorsFreq[arguments[i]-1] < colorsFreq[colorNo-1]) {
 295                        colorNo = arguments[i];
 296                }
 297        }
 298        colorsFreq[colorNo-1]++;
 299        return colorNo;
 300}
 301
 302/**
 303 * given two neigbour <tr> elements, find color which would be different
 304 * from color of both of neighbours; used to 3-color blame table
 305 *
 306 * @param {HTMLElement} tr_prev
 307 * @param {HTMLElement} tr_next
 308 * @returns {Number} color number N such that
 309 * colorN != tr_prev.className && colorN != tr_next.className
 310 */
 311function findColorNo(tr_prev, tr_next) {
 312        var color_prev = getColorNo(tr_prev);
 313        var color_next = getColorNo(tr_next);
 314
 315
 316        // neither of neighbours has color set
 317        // THEN we can use any of 3 possible colors
 318        if (!color_prev && !color_next) {
 319                return chooseColorNoFrom(1,2,3);
 320        }
 321
 322        // either both neighbours have the same color,
 323        // or only one of neighbours have color set
 324        // THEN we can use any color except given
 325        var color;
 326        if (color_prev === color_next) {
 327                color = color_prev; // = color_next;
 328        } else if (!color_prev) {
 329                color = color_next;
 330        } else if (!color_next) {
 331                color = color_prev;
 332        }
 333        if (color) {
 334                return chooseColorNoFrom((color % 3) + 1, ((color+1) % 3) + 1);
 335        }
 336
 337        // neighbours have different colors
 338        // THEN there is only one color left
 339        return (3 - ((color_prev + color_next) % 3));
 340}
 341
 342/* ............................................................ */
 343/* coloring rows like 'blame' after 'blame_data' finishes */
 344
 345/**
 346 * returns true if given row element (tr) is first in commit group
 347 * to be used only after 'blame_data' finishes (after processing)
 348 *
 349 * @param {HTMLElement} tr: table row
 350 * @returns {Boolean} true if TR is first in commit group
 351 */
 352function isStartOfGroup(tr) {
 353        return tr.firstChild.className === 'sha1';
 354}
 355
 356/**
 357 * change colors to use zebra coloring (2 colors) instead of 3 colors
 358 * concatenate neighbour commit groups belonging to the same commit
 359 *
 360 * @globals colorRe
 361 */
 362function fixColorsAndGroups() {
 363        var colorClasses = ['light', 'dark'];
 364        var linenum = 1;
 365        var tr, prev_group;
 366        var colorClass = 0;
 367        var table =
 368                document.getElementById('blame_table') ||
 369                document.getElementsByTagName('table')[0];
 370
 371        while ((tr = document.getElementById('l'+linenum))) {
 372        // index origin is 0, which is table header; start from 1
 373        //while ((tr = table.rows[linenum])) { // <- it is slower
 374                if (isStartOfGroup(tr, linenum, document)) {
 375                        if (prev_group &&
 376                            prev_group.firstChild.firstChild.href ===
 377                                    tr.firstChild.firstChild.href) {
 378                                // we have to concatenate groups
 379                                var prev_rows = prev_group.firstChild.rowSpan || 1;
 380                                var curr_rows =         tr.firstChild.rowSpan || 1;
 381                                prev_group.firstChild.rowSpan = prev_rows + curr_rows;
 382                                //tr.removeChild(tr.firstChild);
 383                                tr.deleteCell(0); // DOM2 HTML way
 384                        } else {
 385                                colorClass = (colorClass + 1) % 2;
 386                                prev_group = tr;
 387                        }
 388                }
 389                var tr_class = tr.className;
 390                tr.className = tr_class.replace(colorRe, colorClasses[colorClass]);
 391                linenum++;
 392        }
 393}
 394
 395/* ............................................................ */
 396/* time and data */
 397
 398/**
 399 * used to extract hours and minutes from timezone info, e.g '-0900'
 400 * @constant
 401 */
 402var tzRe = /^([+-][0-9][0-9])([0-9][0-9])$/;
 403
 404/**
 405 * return date in local time formatted in iso-8601 like format
 406 * 'yyyy-mm-dd HH:MM:SS +/-ZZZZ' e.g. '2005-08-07 21:49:46 +0200'
 407 *
 408 * @param {Number} epoch: seconds since '00:00:00 1970-01-01 UTC'
 409 * @param {String} timezoneInfo: numeric timezone '(+|-)HHMM'
 410 * @returns {String} date in local time in iso-8601 like format
 411 *
 412 * @globals tzRe
 413 */
 414function formatDateISOLocal(epoch, timezoneInfo) {
 415        var match = tzRe.exec(timezoneInfo);
 416        // date corrected by timezone
 417        var localDate = new Date(1000 * (epoch +
 418                (parseInt(match[1],10)*3600 + parseInt(match[2],10)*60)));
 419        var localDateStr = // e.g. '2005-08-07'
 420                localDate.getUTCFullYear()                 + '-' +
 421                padLeft(localDate.getUTCMonth()+1, 2, '0') + '-' +
 422                padLeft(localDate.getUTCDate(),    2, '0');
 423        var localTimeStr = // e.g. '21:49:46'
 424                padLeft(localDate.getUTCHours(),   2, '0') + ':' +
 425                padLeft(localDate.getUTCMinutes(), 2, '0') + ':' +
 426                padLeft(localDate.getUTCSeconds(), 2, '0');
 427
 428        return localDateStr + ' ' + localTimeStr + ' ' + timezoneInfo;
 429}
 430
 431/* ............................................................ */
 432/* unquoting/unescaping filenames */
 433
 434/**#@+
 435 * @constant
 436 */
 437var escCodeRe = /\\([^0-7]|[0-7]{1,3})/g;
 438var octEscRe = /^[0-7]{1,3}$/;
 439var maybeQuotedRe = /^\"(.*)\"$/;
 440/**#@-*/
 441
 442/**
 443 * unquote maybe git-quoted filename
 444 * e.g. 'aa' -> 'aa', '"a\ta"' -> 'a    a'
 445 *
 446 * @param {String} str: git-quoted string
 447 * @returns {String} Unquoted and unescaped string
 448 *
 449 * @globals escCodeRe, octEscRe, maybeQuotedRe
 450 */
 451function unquote(str) {
 452        function unq(seq) {
 453                var es = {
 454                        // character escape codes, aka escape sequences (from C)
 455                        // replacements are to some extent JavaScript specific
 456                        t: "\t",   // tab            (HT, TAB)
 457                        n: "\n",   // newline        (NL)
 458                        r: "\r",   // return         (CR)
 459                        f: "\f",   // form feed      (FF)
 460                        b: "\b",   // backspace      (BS)
 461                        a: "\x07", // alarm (bell)   (BEL)
 462                        e: "\x1B", // escape         (ESC)
 463                        v: "\v"    // vertical tab   (VT)
 464                };
 465
 466                if (seq.search(octEscRe) !== -1) {
 467                        // octal char sequence
 468                        return String.fromCharCode(parseInt(seq, 8));
 469                } else if (seq in es) {
 470                        // C escape sequence, aka character escape code
 471                        return es[seq];
 472                }
 473                // quoted ordinary character
 474                return seq;
 475        }
 476
 477        var match = str.match(maybeQuotedRe);
 478        if (match) {
 479                str = match[1];
 480                // perhaps str = eval('"'+str+'"'); would be enough?
 481                str = str.replace(escCodeRe,
 482                        function (substr, p1, offset, s) { return unq(p1); });
 483        }
 484        return str;
 485}
 486
 487/* ============================================================ */
 488/* main part: parsing response */
 489
 490/**
 491 * Function called for each blame entry, as soon as it finishes.
 492 * It updates page via DOM manipulation, adding sha1 info, etc.
 493 *
 494 * @param {Commit} commit: blamed commit
 495 * @param {Object} group: object representing group of lines,
 496 *                        which blame the same commit (blame entry)
 497 *
 498 * @globals blamedLines
 499 */
 500function handleLine(commit, group) {
 501        /*
 502           This is the structure of the HTML fragment we are working
 503           with:
 504
 505           <tr id="l123" class="">
 506             <td class="sha1" title=""><a href=""> </a></td>
 507             <td class="linenr"><a class="linenr" href="">123</a></td>
 508             <td class="pre"># times (my ext3 doesn&#39;t).</td>
 509           </tr>
 510        */
 511
 512        var resline = group.resline;
 513
 514        // format date and time string only once per commit
 515        if (!commit.info) {
 516                /* e.g. 'Kay Sievers, 2005-08-07 21:49:46 +0200' */
 517                commit.info = commit.author + ', ' +
 518                        formatDateISOLocal(commit.authorTime, commit.authorTimezone);
 519        }
 520
 521        // color depends on group of lines, not only on blamed commit
 522        var colorNo = findColorNo(
 523                document.getElementById('l'+(resline-1)),
 524                document.getElementById('l'+(resline+group.numlines))
 525        );
 526
 527        // loop over lines in commit group
 528        for (var i = 0; i < group.numlines; i++, resline++) {
 529                var tr = document.getElementById('l'+resline);
 530                if (!tr) {
 531                        break;
 532                }
 533                /*
 534                        <tr id="l123" class="">
 535                          <td class="sha1" title=""><a href=""> </a></td>
 536                          <td class="linenr"><a class="linenr" href="">123</a></td>
 537                          <td class="pre"># times (my ext3 doesn&#39;t).</td>
 538                        </tr>
 539                */
 540                var td_sha1  = tr.firstChild;
 541                var a_sha1   = td_sha1.firstChild;
 542                var a_linenr = td_sha1.nextSibling.firstChild;
 543
 544                /* <tr id="l123" class=""> */
 545                var tr_class = '';
 546                if (colorNo !== null) {
 547                        tr_class = 'color'+colorNo;
 548                }
 549                if (commit.boundary) {
 550                        tr_class += ' boundary';
 551                }
 552                if (commit.nprevious === 0) {
 553                        tr_class += ' no-previous';
 554                } else if (commit.nprevious > 1) {
 555                        tr_class += ' multiple-previous';
 556                }
 557                tr.className = tr_class;
 558
 559                /* <td class="sha1" title="?" rowspan="?"><a href="?">?</a></td> */
 560                if (i === 0) {
 561                        td_sha1.title = commit.info;
 562                        td_sha1.rowSpan = group.numlines;
 563
 564                        a_sha1.href = projectUrl + 'a=commit;h=' + commit.sha1;
 565                        if (a_sha1.firstChild) {
 566                                a_sha1.firstChild.data = commit.sha1.substr(0, 8);
 567                        } else {
 568                                a_sha1.appendChild(
 569                                        document.createTextNode(commit.sha1.substr(0, 8)));
 570                        }
 571                        if (group.numlines >= 2) {
 572                                var fragment = document.createDocumentFragment();
 573                                var br   = document.createElement("br");
 574                                var match = commit.author.match(/\b([A-Z])\B/g);
 575                                if (match) {
 576                                        var text = document.createTextNode(
 577                                                        match.join(''));
 578                                }
 579                                if (br && text) {
 580                                        var elem = fragment || td_sha1;
 581                                        elem.appendChild(br);
 582                                        elem.appendChild(text);
 583                                        if (fragment) {
 584                                                td_sha1.appendChild(fragment);
 585                                        }
 586                                }
 587                        }
 588                } else {
 589                        //tr.removeChild(td_sha1); // DOM2 Core way
 590                        tr.deleteCell(0); // DOM2 HTML way
 591                }
 592
 593                /* <td class="linenr"><a class="linenr" href="?">123</a></td> */
 594                var linenr_commit =
 595                        ('previous' in commit ? commit.previous : commit.sha1);
 596                var linenr_filename =
 597                        ('file_parent' in commit ? commit.file_parent : commit.filename);
 598                a_linenr.href = projectUrl + 'a=blame_incremental' +
 599                        ';hb=' + linenr_commit +
 600                        ';f='  + encodeURIComponent(linenr_filename) +
 601                        '#l' + (group.srcline + i);
 602
 603                blamedLines++;
 604
 605                //updateProgressInfo();
 606        }
 607}
 608
 609// ----------------------------------------------------------------------
 610
 611var inProgress = false;   // are we processing response
 612
 613/**#@+
 614 * @constant
 615 */
 616var sha1Re = /^([0-9a-f]{40}) ([0-9]+) ([0-9]+) ([0-9]+)/;
 617var infoRe = /^([a-z-]+) ?(.*)/;
 618var endRe  = /^END ?([^ ]*) ?(.*)/;
 619/**@-*/
 620
 621var curCommit = new Commit();
 622var curGroup  = {};
 623
 624var pollTimer = null;
 625
 626/**
 627 * Parse output from 'git blame --incremental [...]', received via
 628 * XMLHttpRequest from server (blamedataUrl), and call handleLine
 629 * (which updates page) as soon as blame entry is completed.
 630 *
 631 * @param {String[]} lines: new complete lines from blamedata server
 632 *
 633 * @globals commits, curCommit, curGroup, t_interval_server, cmds_server
 634 * @globals sha1Re, infoRe, endRe
 635 */
 636function processBlameLines(lines) {
 637        var match;
 638
 639        for (var i = 0, len = lines.length; i < len; i++) {
 640
 641                if ((match = sha1Re.exec(lines[i]))) {
 642                        var sha1 = match[1];
 643                        var srcline  = parseInt(match[2], 10);
 644                        var resline  = parseInt(match[3], 10);
 645                        var numlines = parseInt(match[4], 10);
 646
 647                        var c = commits[sha1];
 648                        if (!c) {
 649                                c = new Commit(sha1);
 650                                commits[sha1] = c;
 651                        }
 652                        curCommit = c;
 653
 654                        curGroup.srcline = srcline;
 655                        curGroup.resline = resline;
 656                        curGroup.numlines = numlines;
 657
 658                } else if ((match = infoRe.exec(lines[i]))) {
 659                        var info = match[1];
 660                        var data = match[2];
 661                        switch (info) {
 662                        case 'filename':
 663                                curCommit.filename = unquote(data);
 664                                // 'filename' information terminates the entry
 665                                handleLine(curCommit, curGroup);
 666                                updateProgressInfo();
 667                                break;
 668                        case 'author':
 669                                curCommit.author = data;
 670                                break;
 671                        case 'author-time':
 672                                curCommit.authorTime = parseInt(data, 10);
 673                                break;
 674                        case 'author-tz':
 675                                curCommit.authorTimezone = data;
 676                                break;
 677                        case 'previous':
 678                                curCommit.nprevious++;
 679                                // store only first 'previous' header
 680                                if (!'previous' in curCommit) {
 681                                        var parts = data.split(' ', 2);
 682                                        curCommit.previous    = parts[0];
 683                                        curCommit.file_parent = unquote(parts[1]);
 684                                }
 685                                break;
 686                        case 'boundary':
 687                                curCommit.boundary = true;
 688                                break;
 689                        } // end switch
 690
 691                } else if ((match = endRe.exec(lines[i]))) {
 692                        t_interval_server = match[1];
 693                        cmds_server = match[2];
 694
 695                } else if (lines[i] !== '') {
 696                        // malformed line
 697
 698                } // end if (match)
 699
 700        } // end for (lines)
 701}
 702
 703/**
 704 * Process new data and return pointer to end of processed part
 705 *
 706 * @param {String} unprocessed: new data (from nextReadPos)
 707 * @param {Number} nextReadPos: end of last processed data
 708 * @return {Number} end of processed data (new value for nextReadPos)
 709 */
 710function processData(unprocessed, nextReadPos) {
 711        var lastLineEnd = unprocessed.lastIndexOf('\n');
 712        if (lastLineEnd !== -1) {
 713                var lines = unprocessed.substring(0, lastLineEnd).split('\n');
 714                nextReadPos += lastLineEnd + 1 /* 1 == '\n'.length */;
 715
 716                processBlameLines(lines);
 717        } // end if
 718
 719        return nextReadPos;
 720}
 721
 722/**
 723 * Handle XMLHttpRequest errors
 724 *
 725 * @param {XMLHttpRequest} xhr: XMLHttpRequest object
 726 *
 727 * @globals pollTimer, commits, inProgress
 728 */
 729function handleError(xhr) {
 730        errorInfo('Server error: ' +
 731                xhr.status + ' - ' + (xhr.statusText || 'Error contacting server'));
 732
 733        clearInterval(pollTimer);
 734        commits = {}; // free memory
 735
 736        inProgress = false;
 737}
 738
 739/**
 740 * Called after XMLHttpRequest finishes (loads)
 741 *
 742 * @param {XMLHttpRequest} xhr: XMLHttpRequest object (unused)
 743 *
 744 * @globals pollTimer, commits, inProgress
 745 */
 746function responseLoaded(xhr) {
 747        clearInterval(pollTimer);
 748
 749        fixColorsAndGroups();
 750        writeTimeInterval();
 751        commits = {}; // free memory
 752
 753        inProgress = false;
 754}
 755
 756/**
 757 * handler for XMLHttpRequest onreadystatechange event
 758 * @see startBlame
 759 *
 760 * @globals xhr, inProgress
 761 */
 762function handleResponse() {
 763
 764        /*
 765         * xhr.readyState
 766         *
 767         *  Value  Constant (W3C)    Description
 768         *  -------------------------------------------------------------------
 769         *  0      UNSENT            open() has not been called yet.
 770         *  1      OPENED            send() has not been called yet.
 771         *  2      HEADERS_RECEIVED  send() has been called, and headers
 772         *                           and status are available.
 773         *  3      LOADING           Downloading; responseText holds partial data.
 774         *  4      DONE              The operation is complete.
 775         */
 776
 777        if (xhr.readyState !== 4 && xhr.readyState !== 3) {
 778                return;
 779        }
 780
 781        // the server returned error
 782        // try ... catch block is to work around bug in IE8
 783        try {
 784                if (xhr.readyState === 3 && xhr.status !== 200) {
 785                        return;
 786                }
 787        } catch (e) {
 788                return;
 789        }
 790        if (xhr.readyState === 4 && xhr.status !== 200) {
 791                handleError(xhr);
 792                return;
 793        }
 794
 795        // In konqueror xhr.responseText is sometimes null here...
 796        if (xhr.responseText === null) {
 797                return;
 798        }
 799
 800        // in case we were called before finished processing
 801        if (inProgress) {
 802                return;
 803        } else {
 804                inProgress = true;
 805        }
 806
 807        // extract new whole (complete) lines, and process them
 808        while (xhr.prevDataLength !== xhr.responseText.length) {
 809                if (xhr.readyState === 4 &&
 810                    xhr.prevDataLength === xhr.responseText.length) {
 811                        break;
 812                }
 813
 814                xhr.prevDataLength = xhr.responseText.length;
 815                var unprocessed = xhr.responseText.substring(xhr.nextReadPos);
 816                xhr.nextReadPos = processData(unprocessed, xhr.nextReadPos);
 817        } // end while
 818
 819        // did we finish work?
 820        if (xhr.readyState === 4 &&
 821            xhr.prevDataLength === xhr.responseText.length) {
 822                responseLoaded(xhr);
 823        }
 824
 825        inProgress = false;
 826}
 827
 828// ============================================================
 829// ------------------------------------------------------------
 830
 831/**
 832 * Incrementally update line data in blame_incremental view in gitweb.
 833 *
 834 * @param {String} blamedataUrl: URL to server script generating blame data.
 835 * @param {String} bUrl: partial URL to project, used to generate links.
 836 *
 837 * Called from 'blame_incremental' view after loading table with
 838 * file contents, a base for blame view.
 839 *
 840 * @globals xhr, t0, projectUrl, div_progress_bar, totalLines, pollTimer
 841*/
 842function startBlame(blamedataUrl, bUrl) {
 843
 844        xhr = createRequestObject();
 845        if (!xhr) {
 846                errorInfo('ERROR: XMLHttpRequest not supported');
 847                return;
 848        }
 849
 850        t0 = new Date();
 851        projectUrl = bUrl + (bUrl.indexOf('?') === -1 ? '?' : ';');
 852        if ((div_progress_bar = document.getElementById('progress_bar'))) {
 853                //div_progress_bar.setAttribute('style', 'width: 100%;');
 854                div_progress_bar.style.cssText = 'width: 100%;';
 855        }
 856        totalLines = countLines();
 857        updateProgressInfo();
 858
 859        /* add extra properties to xhr object to help processing response */
 860        xhr.prevDataLength = -1;  // used to detect if we have new data
 861        xhr.nextReadPos = 0;      // where unread part of response starts
 862
 863        xhr.onreadystatechange = handleResponse;
 864        //xhr.onreadystatechange = function () { handleResponse(xhr); };
 865
 866        xhr.open('GET', blamedataUrl);
 867        xhr.setRequestHeader('Accept', 'text/plain');
 868        xhr.send(null);
 869
 870        // not all browsers call onreadystatechange event on each server flush
 871        // poll response using timer every second to handle this issue
 872        pollTimer = setInterval(xhr.onreadystatechange, 1000);
 873}
 874
 875// end of gitweb.js