src/blame.c

   1 /* Copyright (c) 2006-2015 Jonas Fonseca <jonas.fonseca@gmail.com>
   2  *
   3  * This program is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU General Public License as
   5  * published by the Free Software Foundation; either version 2 of
   6  * the License, or (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  */
  13
  14 #include "tig/io.h"
  15 #include "tig/refdb.h"
  16 #include "tig/repo.h"
  17 #include "tig/options.h"
  18 #include "tig/parse.h"
  19 #include "tig/display.h"
  20 #include "tig/view.h"
  21 #include "tig/draw.h"
  22 #include "tig/git.h"
  23 #include "tig/diff.h"
  24
  25 /*
  26  * Blame backend
  27  *
  28  * Loading the blame view is a two phase job:
  29  *
  30  *  1. File content is read either using argv_env.file from the
  31  *     filesystem or using git-cat-file.
  32  *  2. Then blame information is incrementally added by
  33  *     reading output from git-blame.
  34  */
  35
  36 struct blame_history_state {
  37         char id[SIZEOF_REV];            /* SHA1 ID. */
  38         const char *filename;           /* Name of file. */
  39 };
  40
  41 static struct view_history blame_view_history = { sizeof(struct blame_history_state) };
  42
  43 struct blame {
  44         struct blame_commit *commit;
  45         unsigned long lineno;
  46         char text[1];
  47 };
  48
  49 struct blame_state {
  50         struct blame_commit *commit;
  51         char author[SIZEOF_STR];
  52         int blamed;
  53         bool done_reading;
  54         bool auto_filename_display;
  55         const char *filename;
  56         /* The history state for the current view is cached in the view
  57          * state so it always matches what was used to load the current blame
  58          * view. */
  59         struct blame_history_state history_state;
  60 };
  61
  62 static void
  63 blame_update_file_name_visibility(struct view *view)
  64 {
  65         struct blame_state *state = view->private;
  66         struct view_column *column = get_view_column(view, VIEW_COLUMN_FILE_NAME);
  67
  68         if (!column)
  69                 return;
  70
  71         column->hidden = column->opt.file_name.display == FILENAME_NO ||
  72                          (column->opt.file_name.display == FILENAME_AUTO &&
  73                           !state->auto_filename_display);
  74 }
  75
  76 static bool
  77 blame_open(struct view *view, enum open_flags flags)
  78 {
  79         struct blame_state *state = view->private;
  80         const char *file_argv[] = { repo.cdup, view->env->file , NULL };
  81         char path[SIZEOF_STR];
  82         size_t i;
  83
  84         if (opt_blame_options) {
  85                 for (i = 0; opt_blame_options[i]; i++) {
  86                         if (prefixcmp(opt_blame_options[i], "-C"))
  87                                 continue;
  88                         state->auto_filename_display = TRUE;
  89                 }
  90         }
  91
  92         blame_update_file_name_visibility(view);
  93
  94         if (is_initial_view(view)) {
  95                 /* Finish validating and setting up blame options */
  96                 if (!opt_file_args || opt_file_args[1] || (opt_rev_args && opt_rev_args[1]))
  97                         usage("Invalid number of options to blame");
  98
  99                 if (opt_rev_args) {
 100                         string_ncopy(view->env->ref, opt_rev_args[0], strlen(opt_rev_args[0]));
 101                 }
 102
 103                 string_ncopy(view->env->file, opt_file_args[0], strlen(opt_file_args[0]));
 104
 105                 opt_blame_options = opt_cmdline_args;
 106                 opt_cmdline_args = NULL;
 107         }
 108
 109         if (!view->env->file[0]) {
 110                 report("No file chosen, press %s to open tree view",
 111                         get_view_key(view, REQ_VIEW_TREE));
 112                 return FALSE;
 113         }
 114
 115         if (!view->prev && *repo.prefix && !(flags & (OPEN_RELOAD | OPEN_REFRESH))) {
 116                 string_copy(path, view->env->file);
 117                 if (!string_format(view->env->file, "%s%s", repo.prefix, path)) {
 118                         report("Failed to setup the blame view");
 119                         return FALSE;
 120                 }
 121         }
 122
 123         if (*view->env->ref || !begin_update(view, repo.cdup, file_argv, flags)) {
 124                 const char *blame_cat_file_argv[] = {
 125                         "git", "cat-file", "blob", "%(ref):%(file)", NULL
 126                 };
 127
 128                 if (!begin_update(view, repo.cdup, blame_cat_file_argv, flags))
 129                         return FALSE;
 130         }
 131
 132         /* First pass: remove multiple references to the same commit. */
 133         for (i = 0; i < view->lines; i++) {
 134                 struct blame *blame = view->line[i].data;
 135
 136                 if (blame->commit && blame->commit->id[0])
 137                         blame->commit->id[0] = 0;
 138                 else
 139                         blame->commit = NULL;
 140         }
 141
 142         /* Second pass: free existing references. */
 143         for (i = 0; i < view->lines; i++) {
 144                 struct blame *blame = view->line[i].data;
 145
 146                 if (blame->commit)
 147                         free(blame->commit);
 148         }
 149
 150         if (!(flags & OPEN_RELOAD))
 151                 reset_view_history(&blame_view_history);
 152         string_copy_rev(state->history_state.id, view->env->ref);
 153         state->history_state.filename = get_path(view->env->file);
 154         if (!state->history_state.filename)
 155                 return FALSE;
 156         string_format(view->vid, "%s", view->env->file);
 157         string_format(view->ref, "%s ...", view->env->file);
 158
 159         return TRUE;
 160 }
 161
 162 static struct blame_commit *
 163 get_blame_commit(struct view *view, const char *id)
 164 {
 165         size_t i;
 166
 167         for (i = 0; i < view->lines; i++) {
 168                 struct blame *blame = view->line[i].data;
 169
 170                 if (!blame->commit)
 171                         continue;
 172
 173                 if (!strncmp(blame->commit->id, id, SIZEOF_REV - 1))
 174                         return blame->commit;
 175         }
 176
 177         {
 178                 struct blame_commit *commit = calloc(1, sizeof(*commit));
 179
 180                 if (commit)
 181                         string_ncopy(commit->id, id, SIZEOF_REV);
 182                 return commit;
 183         }
 184 }
 185
 186 static struct blame_commit *
 187 read_blame_commit(struct view *view, const char *text, struct blame_state *state)
 188 {
 189         struct blame_header header;
 190         struct blame_commit *commit;
 191         struct blame *blame;
 192
 193         if (!parse_blame_header(&header, text, view->lines))
 194                 return NULL;
 195
 196         commit = get_blame_commit(view, text);
 197         if (!commit)
 198                 return NULL;
 199
 200         state->blamed += header.group;
 201         while (header.group--) {
 202                 struct line *line = &view->line[header.lineno + header.group - 1];
 203
 204                 blame = line->data;
 205                 blame->commit = commit;
 206                 blame->lineno = header.orig_lineno + header.group - 1;
 207                 line->dirty = 1;
 208         }
 209
 210         return commit;
 211 }
 212
 213 static bool
 214 blame_read_file(struct view *view, struct buffer *buf, struct blame_state *state)
 215 {
 216         if (!buf) {
 217                 const char *blame_argv[] = {
 218                         "git", "blame", encoding_arg, "%(blameargs)", "--incremental",
 219                                 *view->env->ref ? view->env->ref : "--incremental", "--", view->env->file, NULL
 220                 };
 221
 222                 if (failed_to_load_initial_view(view))
 223                         die("No blame exist for %s", view->vid);
 224
 225                 if (view->lines == 0 || !begin_update(view, repo.cdup, blame_argv, OPEN_EXTRA)) {
 226                         report("Failed to load blame data");
 227                         return TRUE;
 228                 }
 229
 230                 if (view->env->goto_lineno > 0) {
 231                         select_view_line(view, view->env->goto_lineno);
 232                         view->env->goto_lineno = 0;
 233                 }
 234
 235                 state->done_reading = TRUE;
 236                 return FALSE;
 237
 238         } else {
 239                 struct blame *blame;
 240
 241                 if (!add_line_alloc(view, &blame, LINE_DEFAULT, buf->size, FALSE))
 242                         return FALSE;
 243
 244                 blame->commit = NULL;
 245                 strncpy(blame->text, buf->data, buf->size);
 246                 blame->text[buf->size] = 0;
 247                 return TRUE;
 248         }
 249 }
 250
 251 static bool
 252 blame_read(struct view *view, struct buffer *buf)
 253 {
 254         struct blame_state *state = view->private;
 255
 256         if (!state->done_reading)
 257                 return blame_read_file(view, buf, state);
 258
 259         if (!buf) {
 260                 string_format(view->ref, "%s", view->vid);
 261                 if (view_is_displayed(view)) {
 262                         update_view_title(view);
 263                         redraw_view_from(view, 0);
 264                 }
 265                 return TRUE;
 266         }
 267
 268         if (!state->commit) {
 269                 state->commit = read_blame_commit(view, buf->data, state);
 270                 string_format(view->ref, "%s %2zd%%", view->vid,
 271                               view->lines ? state->blamed * 100 / view->lines : 0);
 272
 273         } else if (parse_blame_info(state->commit, state->author, buf->data)) {
 274                 bool update_view_columns = TRUE;
 275                 int i;
 276
 277                 if (!state->commit->filename)
 278                         return FALSE;
 279
 280                 if (!state->filename) {
 281                         state->filename = state->commit->filename;
 282                 } else if (strcmp(state->filename, state->commit->filename)) {
 283                         state->auto_filename_display = TRUE;
 284                         view->force_redraw = TRUE;
 285                         blame_update_file_name_visibility(view);
 286                 }
 287
 288                 for (i = 0; i < view->lines; i++) {
 289                         struct line *line = &view->line[i];
 290                         struct blame *blame = line->data;
 291
 292                         if (blame && blame->commit == state->commit) {
 293                                 line->dirty = 1;
 294                                 if (update_view_columns)
 295                                         view_column_info_update(view, line);
 296                                 update_view_columns = FALSE;
 297                         }
 298                 }
 299
 300                 state->commit = NULL;
 301         }
 302
 303         return TRUE;
 304 }
 305
 306 bool
 307 blame_get_column_data(struct view *view, const struct line *line, struct view_column_data *column_data)
 308 {
 309         struct blame *blame = line->data;
 310
 311         if (blame->commit) {
 312                 column_data->id = blame->commit->id;
 313                 column_data->author = blame->commit->author;
 314                 column_data->file_name = blame->commit->filename;
 315                 column_data->date = &blame->commit->time;
 316                 column_data->commit_title = blame->commit->title;
 317         }
 318
 319         column_data->text = blame->text;
 320
 321         return TRUE;
 322 }
 323
 324 static bool
 325 check_blame_commit(struct blame *blame, bool check_null_id)
 326 {
 327         if (!blame->commit)
 328                 report("Commit data not loaded yet");
 329         else if (check_null_id && string_rev_is_null(blame->commit->id))
 330                 report("No commit exist for the selected line");
 331         else
 332                 return TRUE;
 333         return FALSE;
 334 }
 335
 336 static void
 337 setup_blame_parent_line(struct view *view, struct blame *blame)
 338 {
 339         char from[SIZEOF_REF + SIZEOF_STR];
 340         char to[SIZEOF_REF + SIZEOF_STR];
 341         const char *diff_tree_argv[] = {
 342                 "git", "diff", encoding_arg, "--no-textconv", "--no-ext-diff",
 343                         "--no-color", "-U0", from, to, "--", NULL
 344         };
 345         struct io io;
 346         int parent_lineno = -1;
 347         int blamed_lineno = -1;
 348         struct buffer buf;
 349
 350         if (!string_format(from, "%s:%s", view->env->ref, view->env->file) ||
 351             !string_format(to, "%s:%s", blame->commit->id, blame->commit->filename) ||
 352             !io_run(&io, IO_RD, NULL, opt_env, diff_tree_argv))
 353                 return;
 354
 355         while (io_get(&io, &buf, '\n', TRUE)) {
 356                 char *line = buf.data;
 357
 358                 if (*line == '@') {
 359                         char *pos = strchr(line, '+');
 360
 361                         parent_lineno = atoi(line + 4);
 362                         if (pos)
 363                                 blamed_lineno = atoi(pos + 1);
 364
 365                 } else if (*line == '+' && parent_lineno != -1) {
 366                         if (blame->lineno == blamed_lineno - 1 &&
 367                             !strcmp(blame->text, line + 1)) {
 368                                 view->pos.lineno = parent_lineno ? parent_lineno - 1 : 0;
 369                                 break;
 370                         }
 371                         blamed_lineno++;
 372                 }
 373         }
 374
 375         io_done(&io);
 376 }
 377
 378 static void
 379 blame_go_forward(struct view *view, struct blame *blame, bool parent)
 380 {
 381         struct blame_state *state = view->private;
 382         struct blame_history_state *history_state = &state->history_state;
 383         struct blame_commit *commit = blame->commit;
 384         const char *id = parent ? commit->parent_id : commit->id;
 385         const char *filename = parent ? commit->parent_filename : commit->filename;
 386
 387         if (!*id && parent) {
 388                 report("The selected commit has no parents");
 389                 return;
 390         }
 391
 392         if (!strcmp(history_state->id, id) && !strcmp(history_state->filename, filename)) {
 393                 report("The selected commit is already displayed");
 394                 return;
 395         }
 396
 397         if (!push_view_history_state(&blame_view_history, &view->pos, history_state)) {
 398                 report("Failed to save current view state");
 399                 return;
 400         }
 401
 402         string_ncopy(view->env->ref, id, sizeof(commit->id));
 403         string_ncopy(view->env->file, filename, strlen(filename));
 404         if (parent)
 405                 setup_blame_parent_line(view, blame);
 406         view->env->goto_lineno = blame->lineno;
 407         reload_view(view);
 408 }
 409
 410 static void
 411 blame_go_back(struct view *view)
 412 {
 413         struct blame_history_state history_state;
 414
 415         if (!pop_view_history_state(&blame_view_history, &view->pos, &history_state)) {
 416                 report("Already at start of history");
 417                 return;
 418         }
 419
 420         string_copy(view->env->ref, history_state.id);
 421         string_ncopy(view->env->file, history_state.filename, strlen(history_state.filename));
 422         view->env->goto_lineno = view->pos.lineno;
 423         reload_view(view);
 424 }
 425
 426 static enum request
 427 blame_request(struct view *view, enum request request, struct line *line)
 428 {
 429         enum open_flags flags = view_is_displayed(view) ? OPEN_SPLIT : OPEN_DEFAULT;
 430         struct blame *blame = line->data;
 431         struct view *diff = &diff_view;
 432
 433         switch (request) {
 434         case REQ_VIEW_BLAME:
 435         case REQ_PARENT:
 436                 if (!check_blame_commit(blame, request == REQ_VIEW_BLAME))
 437                         break;
 438                 blame_go_forward(view, blame, request == REQ_PARENT);
 439                 break;
 440
 441         case REQ_BACK:
 442                 blame_go_back(view);
 443                 break;
 444
 445         case REQ_ENTER:
 446                 if (!check_blame_commit(blame, FALSE))
 447                         break;
 448
 449                 if (view_is_displayed(diff) &&
 450                     !strcmp(blame->commit->id, diff->ref))
 451                         break;
 452
 453                 if (string_rev_is_null(blame->commit->id)) {
 454                         const char *diff_parent_argv[] = {
 455                                 GIT_DIFF_BLAME(encoding_arg,
 456                                         diff_context_arg(),
 457                                         ignore_space_arg(),
 458                                         blame->commit->filename)
 459                         };
 460                         const char *diff_no_parent_argv[] = {
 461                                 GIT_DIFF_BLAME_NO_PARENT(encoding_arg,
 462                                         diff_context_arg(),
 463                                         ignore_space_arg(),
 464                                         blame->commit->filename)
 465                         };
 466                         const char **diff_index_argv = *blame->commit->parent_id
 467                                 ? diff_parent_argv : diff_no_parent_argv;
 468
 469                         open_argv(view, diff, diff_index_argv, NULL, flags);
 470                         if (diff->pipe)
 471                                 string_copy_rev(diff->ref, NULL_ID);
 472                 } else {
 473                         open_diff_view(view, flags);
 474                 }
 475                 break;
 476
 477         default:
 478                 return request;
 479         }
 480
 481         return REQ_NONE;
 482 }
 483
 484 static void
 485 blame_select(struct view *view, struct line *line)
 486 {
 487         struct blame *blame = line->data;
 488         struct blame_commit *commit = blame->commit;
 489
 490         if (!commit)
 491                 return;
 492
 493         if (string_rev_is_null(commit->id))
 494                 string_ncopy(view->env->commit, "HEAD", 4);
 495         else
 496                 string_copy_rev(view->env->commit, commit->id);
 497
 498         if (commit->filename)
 499                 string_format(view->env->file, "%s", commit->filename);
 500         view->env->lineno = view->pos.lineno + 1;
 501 }
 502
 503 static struct view_ops blame_ops = {
 504         "line",
 505         argv_env.commit,
 506         VIEW_SEND_CHILD_ENTER | VIEW_BLAME_LIKE,
 507         sizeof(struct blame_state),
 508         blame_open,
 509         blame_read,
 510         view_column_draw,
 511         blame_request,
 512         view_column_grep,
 513         blame_select,
 514         NULL,
 515         view_column_bit(AUTHOR) | view_column_bit(DATE) |
 516                 view_column_bit(FILE_NAME) | view_column_bit(ID) |
 517                 view_column_bit(LINE_NUMBER) | view_column_bit(TEXT),
 518         blame_get_column_data,
 519 };
 520
 521 DEFINE_VIEW(blame);
 522
 523 /* vim: set ts=8 sw=8 noexpandtab: */