add-patch.c

   1 #include "cache.h"
   2 #include "add-interactive.h"
   3 #include "strbuf.h"
   4 #include "run-command.h"
   5 #include "argv-array.h"
   6 #include "pathspec.h"
   7 #include "color.h"
   8 #include "diff.h"
   9
  10 struct hunk_header {
  11         unsigned long old_offset, old_count, new_offset, new_count;
  12         /*
  13          * Start/end offsets to the extra text after the second `@@` in the
  14          * hunk header, e.g. the function signature. This is expected to
  15          * include the newline.
  16          */
  17         size_t extra_start, extra_end, colored_extra_start, colored_extra_end;
  18 };
  19
  20 struct hunk {
  21         size_t start, end, colored_start, colored_end;
  22         enum { UNDECIDED_HUNK = 0, SKIP_HUNK, USE_HUNK } use;
  23         struct hunk_header header;
  24 };
  25
  26 struct add_p_state {
  27         struct add_i_state s;
  28         struct strbuf answer, buf;
  29
  30         /* parsed diff */
  31         struct strbuf plain, colored;
  32         struct file_diff {
  33                 struct hunk head;
  34                 struct hunk *hunk;
  35                 size_t hunk_nr, hunk_alloc;
  36                 unsigned deleted:1;
  37         } *file_diff;
  38         size_t file_diff_nr;
  39 };
  40
  41 static void err(struct add_p_state *s, const char *fmt, ...)
  42 {
  43         va_list args;
  44
  45         va_start(args, fmt);
  46         fputs(s->s.error_color, stderr);
  47         vfprintf(stderr, fmt, args);
  48         fputs(s->s.reset_color, stderr);
  49         fputc('\n', stderr);
  50         va_end(args);
  51 }
  52
  53 static void setup_child_process(struct add_p_state *s,
  54                                 struct child_process *cp, ...)
  55 {
  56         va_list ap;
  57         const char *arg;
  58
  59         va_start(ap, cp);
  60         while ((arg = va_arg(ap, const char *)))
  61                 argv_array_push(&cp->args, arg);
  62         va_end(ap);
  63
  64         cp->git_cmd = 1;
  65         argv_array_pushf(&cp->env_array,
  66                          INDEX_ENVIRONMENT "=%s", s->s.r->index_file);
  67 }
  68
  69 static int parse_range(const char **p,
  70                        unsigned long *offset, unsigned long *count)
  71 {
  72         char *pend;
  73
  74         *offset = strtoul(*p, &pend, 10);
  75         if (pend == *p)
  76                 return -1;
  77         if (*pend != ',') {
  78                 *count = 1;
  79                 *p = pend;
  80                 return 0;
  81         }
  82         *count = strtoul(pend + 1, (char **)p, 10);
  83         return *p == pend + 1 ? -1 : 0;
  84 }
  85
  86 static int parse_hunk_header(struct add_p_state *s, struct hunk *hunk)
  87 {
  88         struct hunk_header *header = &hunk->header;
  89         const char *line = s->plain.buf + hunk->start, *p = line;
  90         char *eol = memchr(p, '\n', s->plain.len - hunk->start);
  91
  92         if (!eol)
  93                 eol = s->plain.buf + s->plain.len;
  94
  95         if (!skip_prefix(p, "@@ -", &p) ||
  96             parse_range(&p, &header->old_offset, &header->old_count) < 0 ||
  97             !skip_prefix(p, " +", &p) ||
  98             parse_range(&p, &header->new_offset, &header->new_count) < 0 ||
  99             !skip_prefix(p, " @@", &p))
 100                 return error(_("could not parse hunk header '%.*s'"),
 101                              (int)(eol - line), line);
 102
 103         hunk->start = eol - s->plain.buf + (*eol == '\n');
 104         header->extra_start = p - s->plain.buf;
 105         header->extra_end = hunk->start;
 106
 107         if (!s->colored.len) {
 108                 header->colored_extra_start = header->colored_extra_end = 0;
 109                 return 0;
 110         }
 111
 112         /* Now find the extra text in the colored diff */
 113         line = s->colored.buf + hunk->colored_start;
 114         eol = memchr(line, '\n', s->colored.len - hunk->colored_start);
 115         if (!eol)
 116                 eol = s->colored.buf + s->colored.len;
 117         p = memmem(line, eol - line, "@@ -", 4);
 118         if (!p)
 119                 return error(_("could not parse colored hunk header '%.*s'"),
 120                              (int)(eol - line), line);
 121         p = memmem(p + 4, eol - p - 4, " @@", 3);
 122         if (!p)
 123                 return error(_("could not parse colored hunk header '%.*s'"),
 124                              (int)(eol - line), line);
 125         hunk->colored_start = eol - s->colored.buf + (*eol == '\n');
 126         header->colored_extra_start = p + 3 - s->colored.buf;
 127         header->colored_extra_end = hunk->colored_start;
 128
 129         return 0;
 130 }
 131
 132 static int parse_diff(struct add_p_state *s, const struct pathspec *ps)
 133 {
 134         struct argv_array args = ARGV_ARRAY_INIT;
 135         struct strbuf *plain = &s->plain, *colored = NULL;
 136         struct child_process cp = CHILD_PROCESS_INIT;
 137         char *p, *pend, *colored_p = NULL, *colored_pend = NULL;
 138         size_t file_diff_alloc = 0, i, color_arg_index;
 139         struct file_diff *file_diff = NULL;
 140         struct hunk *hunk = NULL;
 141         int res;
 142
 143         /* Use `--no-color` explicitly, just in case `diff.color = always`. */
 144         argv_array_pushl(&args, "diff-files", "-p", "--no-color", "--", NULL);
 145         color_arg_index = args.argc - 2;
 146         for (i = 0; i < ps->nr; i++)
 147                 argv_array_push(&args, ps->items[i].original);
 148
 149         setup_child_process(s, &cp, NULL);
 150         cp.argv = args.argv;
 151         res = capture_command(&cp, plain, 0);
 152         if (res) {
 153                 argv_array_clear(&args);
 154                 return error(_("could not parse diff"));
 155         }
 156         if (!plain->len) {
 157                 argv_array_clear(&args);
 158                 return 0;
 159         }
 160         strbuf_complete_line(plain);
 161
 162         if (want_color_fd(1, -1)) {
 163                 struct child_process colored_cp = CHILD_PROCESS_INIT;
 164
 165                 setup_child_process(s, &colored_cp, NULL);
 166                 xsnprintf((char *)args.argv[color_arg_index], 8, "--color");
 167                 colored_cp.argv = args.argv;
 168                 colored = &s->colored;
 169                 res = capture_command(&colored_cp, colored, 0);
 170                 argv_array_clear(&args);
 171                 if (res)
 172                         return error(_("could not parse colored diff"));
 173                 strbuf_complete_line(colored);
 174                 colored_p = colored->buf;
 175                 colored_pend = colored_p + colored->len;
 176         }
 177         argv_array_clear(&args);
 178
 179         /* parse files and hunks */
 180         p = plain->buf;
 181         pend = p + plain->len;
 182         while (p != pend) {
 183                 char *eol = memchr(p, '\n', pend - p);
 184                 const char *deleted = NULL;
 185
 186                 if (!eol)
 187                         eol = pend;
 188
 189                 if (starts_with(p, "diff ")) {
 190                         s->file_diff_nr++;
 191                         ALLOC_GROW(s->file_diff, s->file_diff_nr,
 192                                    file_diff_alloc);
 193                         file_diff = s->file_diff + s->file_diff_nr - 1;
 194                         memset(file_diff, 0, sizeof(*file_diff));
 195                         hunk = &file_diff->head;
 196                         hunk->start = p - plain->buf;
 197                         if (colored_p)
 198                                 hunk->colored_start = colored_p - colored->buf;
 199                 } else if (p == plain->buf)
 200                         BUG("diff starts with unexpected line:\n"
 201                             "%.*s\n", (int)(eol - p), p);
 202                 else if (file_diff->deleted)
 203                         ; /* keep the rest of the file in a single "hunk" */
 204                 else if (starts_with(p, "@@ ") ||
 205                          (hunk == &file_diff->head &&
 206                           skip_prefix(p, "deleted file", &deleted))) {
 207                         file_diff->hunk_nr++;
 208                         ALLOC_GROW(file_diff->hunk, file_diff->hunk_nr,
 209                                    file_diff->hunk_alloc);
 210                         hunk = file_diff->hunk + file_diff->hunk_nr - 1;
 211                         memset(hunk, 0, sizeof(*hunk));
 212
 213                         hunk->start = p - plain->buf;
 214                         if (colored)
 215                                 hunk->colored_start = colored_p - colored->buf;
 216
 217                         if (deleted)
 218                                 file_diff->deleted = 1;
 219                         else if (parse_hunk_header(s, hunk) < 0)
 220                                 return -1;
 221                 }
 222
 223                 p = eol == pend ? pend : eol + 1;
 224                 hunk->end = p - plain->buf;
 225
 226                 if (colored) {
 227                         char *colored_eol = memchr(colored_p, '\n',
 228                                                    colored_pend - colored_p);
 229                         if (colored_eol)
 230                                 colored_p = colored_eol + 1;
 231                         else
 232                                 colored_p = colored_pend;
 233
 234                         hunk->colored_end = colored_p - colored->buf;
 235                 }
 236         }
 237
 238         return 0;
 239 }
 240
 241 static void render_hunk(struct add_p_state *s, struct hunk *hunk,
 242                         ssize_t delta, int colored, struct strbuf *out)
 243 {
 244         struct hunk_header *header = &hunk->header;
 245
 246         if (hunk->header.old_offset != 0 || hunk->header.new_offset != 0) {
 247                 /*
 248                  * Generate the hunk header dynamically, except for special
 249                  * hunks (such as the diff header).
 250                  */
 251                 const char *p;
 252                 size_t len;
 253                 unsigned long old_offset = header->old_offset;
 254                 unsigned long new_offset = header->new_offset;
 255
 256                 if (!colored) {
 257                         p = s->plain.buf + header->extra_start;
 258                         len = header->extra_end - header->extra_start;
 259                 } else {
 260                         strbuf_addstr(out, s->s.fraginfo_color);
 261                         p = s->colored.buf + header->colored_extra_start;
 262                         len = header->colored_extra_end
 263                                 - header->colored_extra_start;
 264                 }
 265
 266                 new_offset += delta;
 267
 268                 strbuf_addf(out, "@@ -%lu,%lu +%lu,%lu @@",
 269                             old_offset, header->old_count,
 270                             new_offset, header->new_count);
 271                 if (len)
 272                         strbuf_add(out, p, len);
 273                 else if (colored)
 274                         strbuf_addf(out, "%s\n", GIT_COLOR_RESET);
 275                 else
 276                         strbuf_addch(out, '\n');
 277         }
 278
 279         if (colored)
 280                 strbuf_add(out, s->colored.buf + hunk->colored_start,
 281                            hunk->colored_end - hunk->colored_start);
 282         else
 283                 strbuf_add(out, s->plain.buf + hunk->start,
 284                            hunk->end - hunk->start);
 285 }
 286
 287 static void reassemble_patch(struct add_p_state *s,
 288                              struct file_diff *file_diff, struct strbuf *out)
 289 {
 290         struct hunk *hunk;
 291         size_t i;
 292         ssize_t delta = 0;
 293
 294         render_hunk(s, &file_diff->head, 0, 0, out);
 295
 296         for (i = 0; i < file_diff->hunk_nr; i++) {
 297                 hunk = file_diff->hunk + i;
 298                 if (hunk->use != USE_HUNK)
 299                         delta += hunk->header.old_count
 300                                 - hunk->header.new_count;
 301                 else
 302                         render_hunk(s, hunk, delta, 0, out);
 303         }
 304 }
 305
 306 static const char help_patch_text[] =
 307 N_("y - stage this hunk\n"
 308    "n - do not stage this hunk\n"
 309    "a - stage this and all the remaining hunks\n"
 310    "d - do not stage this hunk nor any of the remaining hunks\n"
 311    "j - leave this hunk undecided, see next undecided hunk\n"
 312    "J - leave this hunk undecided, see next hunk\n"
 313    "k - leave this hunk undecided, see previous undecided hunk\n"
 314    "K - leave this hunk undecided, see previous hunk\n"
 315    "? - print help\n");
 316
 317 static int patch_update_file(struct add_p_state *s,
 318                              struct file_diff *file_diff)
 319 {
 320         size_t hunk_index = 0;
 321         ssize_t i, undecided_previous, undecided_next;
 322         struct hunk *hunk;
 323         char ch;
 324         struct child_process cp = CHILD_PROCESS_INIT;
 325         int colored = !!s->colored.len;
 326
 327         if (!file_diff->hunk_nr)
 328                 return 0;
 329
 330         strbuf_reset(&s->buf);
 331         render_hunk(s, &file_diff->head, 0, colored, &s->buf);
 332         fputs(s->buf.buf, stdout);
 333         for (;;) {
 334                 if (hunk_index >= file_diff->hunk_nr)
 335                         hunk_index = 0;
 336                 hunk = file_diff->hunk + hunk_index;
 337
 338                 undecided_previous = -1;
 339                 for (i = hunk_index - 1; i >= 0; i--)
 340                         if (file_diff->hunk[i].use == UNDECIDED_HUNK) {
 341                                 undecided_previous = i;
 342                                 break;
 343                         }
 344
 345                 undecided_next = -1;
 346                 for (i = hunk_index + 1; i < file_diff->hunk_nr; i++)
 347                         if (file_diff->hunk[i].use == UNDECIDED_HUNK) {
 348                                 undecided_next = i;
 349                                 break;
 350                         }
 351
 352                 /* Everything decided? */
 353                 if (undecided_previous < 0 && undecided_next < 0 &&
 354                     hunk->use != UNDECIDED_HUNK)
 355                         break;
 356
 357                 strbuf_reset(&s->buf);
 358                 render_hunk(s, hunk, 0, colored, &s->buf);
 359                 fputs(s->buf.buf, stdout);
 360
 361                 strbuf_reset(&s->buf);
 362                 if (undecided_previous >= 0)
 363                         strbuf_addstr(&s->buf, ",k");
 364                 if (hunk_index)
 365                         strbuf_addstr(&s->buf, ",K");
 366                 if (undecided_next >= 0)
 367                         strbuf_addstr(&s->buf, ",j");
 368                 if (hunk_index + 1 < file_diff->hunk_nr)
 369                         strbuf_addstr(&s->buf, ",J");
 370                 color_fprintf(stdout, s->s.prompt_color,
 371                               "(%"PRIuMAX"/%"PRIuMAX") ",
 372                               (uintmax_t)hunk_index + 1,
 373                               (uintmax_t)file_diff->hunk_nr);
 374                 color_fprintf(stdout, s->s.prompt_color,
 375                               _("Stage this hunk [y,n,a,d%s,?]? "),
 376                               s->buf.buf);
 377                 fflush(stdout);
 378                 if (strbuf_getline(&s->answer, stdin) == EOF)
 379                         break;
 380                 strbuf_trim_trailing_newline(&s->answer);
 381
 382                 if (!s->answer.len)
 383                         continue;
 384                 ch = tolower(s->answer.buf[0]);
 385                 if (ch == 'y') {
 386                         hunk->use = USE_HUNK;
 387 soft_increment:
 388                         hunk_index = undecided_next < 0 ?
 389                                 file_diff->hunk_nr : undecided_next;
 390                 } else if (ch == 'n') {
 391                         hunk->use = SKIP_HUNK;
 392                         goto soft_increment;
 393                 } else if (ch == 'a') {
 394                         for (; hunk_index < file_diff->hunk_nr; hunk_index++) {
 395                                 hunk = file_diff->hunk + hunk_index;
 396                                 if (hunk->use == UNDECIDED_HUNK)
 397                                         hunk->use = USE_HUNK;
 398                         }
 399                 } else if (ch == 'd') {
 400                         for (; hunk_index < file_diff->hunk_nr; hunk_index++) {
 401                                 hunk = file_diff->hunk + hunk_index;
 402                                 if (hunk->use == UNDECIDED_HUNK)
 403                                         hunk->use = SKIP_HUNK;
 404                         }
 405                 } else if (s->answer.buf[0] == 'K') {
 406                         if (hunk_index)
 407                                 hunk_index--;
 408                         else
 409                                 err(s, _("No previous hunk"));
 410                 } else if (s->answer.buf[0] == 'J') {
 411                         if (hunk_index + 1 < file_diff->hunk_nr)
 412                                 hunk_index++;
 413                         else
 414                                 err(s, _("No next hunk"));
 415                 } else if (s->answer.buf[0] == 'k') {
 416                         if (undecided_previous >= 0)
 417                                 hunk_index = undecided_previous;
 418                         else
 419                                 err(s, _("No previous hunk"));
 420                 } else if (s->answer.buf[0] == 'j') {
 421                         if (undecided_next >= 0)
 422                                 hunk_index = undecided_next;
 423                         else
 424                                 err(s, _("No next hunk"));
 425                 } else
 426                         color_fprintf(stdout, s->s.help_color,
 427                                       _(help_patch_text));
 428         }
 429
 430         /* Any hunk to be used? */
 431         for (i = 0; i < file_diff->hunk_nr; i++)
 432                 if (file_diff->hunk[i].use == USE_HUNK)
 433                         break;
 434
 435         if (i < file_diff->hunk_nr) {
 436                 /* At least one hunk selected: apply */
 437                 strbuf_reset(&s->buf);
 438                 reassemble_patch(s, file_diff, &s->buf);
 439
 440                 discard_index(s->s.r->index);
 441                 setup_child_process(s, &cp, "apply", "--cached", NULL);
 442                 if (pipe_command(&cp, s->buf.buf, s->buf.len,
 443                                  NULL, 0, NULL, 0))
 444                         error(_("'git apply --cached' failed"));
 445                 if (!repo_read_index(s->s.r))
 446                         repo_refresh_and_write_index(s->s.r, REFRESH_QUIET, 0,
 447                                                      1, NULL, NULL, NULL);
 448         }
 449
 450         putchar('\n');
 451         return 0;
 452 }
 453
 454 int run_add_p(struct repository *r, const struct pathspec *ps)
 455 {
 456         struct add_p_state s = {
 457                 { r }, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT, STRBUF_INIT
 458         };
 459         size_t i;
 460
 461         init_add_i_state(&s.s, r);
 462
 463         if (discard_index(r->index) < 0 || repo_read_index(r) < 0 ||
 464             repo_refresh_and_write_index(r, REFRESH_QUIET, 0, 1,
 465                                          NULL, NULL, NULL) < 0 ||
 466             parse_diff(&s, ps) < 0) {
 467                 strbuf_release(&s.plain);
 468                 strbuf_release(&s.colored);
 469                 return -1;
 470         }
 471
 472         for (i = 0; i < s.file_diff_nr; i++)
 473                 if (patch_update_file(&s, s.file_diff + i))
 474                         break;
 475
 476         strbuf_release(&s.answer);
 477         strbuf_release(&s.buf);
 478         strbuf_release(&s.plain);
 479         strbuf_release(&s.colored);
 480         return 0;
 481 }