src/refspec.c

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7
   8 #include "refspec.h"
   9
  10 #include "git2/errors.h"
  11
  12 #include "refs.h"
  13 #include "util.h"
  14 #include "vector.h"
  15 #include "wildmatch.h"
  16
  17 int git_refspec__parse(git_refspec *refspec, const char *input, bool is_fetch)
  18 {
  19         /* Ported from https://github.com/git/git/blob/f06d47e7e0d9db709ee204ed13a8a7486149f494/remote.c#L518-636 */
  20
  21         size_t llen;
  22         int is_glob = 0;
  23         const char *lhs, *rhs;
  24         int valid = 0;
  25         unsigned int flags;
  26
  27         GIT_ASSERT_ARG(refspec);
  28         GIT_ASSERT_ARG(input);
  29
  30         memset(refspec, 0x0, sizeof(git_refspec));
  31         refspec->push = !is_fetch;
  32
  33         lhs = input;
  34         if (*lhs == '+') {
  35                 refspec->force = 1;
  36                 lhs++;
  37         }
  38
  39         rhs = strrchr(lhs, ':');
  40
  41         /*
  42          * Before going on, special case ":" (or "+:") as a refspec
  43          * for matching refs.
  44          */
  45         if (!is_fetch && rhs == lhs && rhs[1] == '\0') {
  46                 refspec->matching = 1;
  47                 refspec->string = git__strdup(input);
  48                 GIT_ERROR_CHECK_ALLOC(refspec->string);
  49                 refspec->src = git__strdup("");
  50                 GIT_ERROR_CHECK_ALLOC(refspec->src);
  51                 refspec->dst = git__strdup("");
  52                 GIT_ERROR_CHECK_ALLOC(refspec->dst);
  53                 return 0;
  54         }
  55
  56         if (rhs) {
  57                 size_t rlen = strlen(++rhs);
  58                 if (rlen || !is_fetch) {
  59                         is_glob = (1 <= rlen && strchr(rhs, '*'));
  60                         refspec->dst = git__strndup(rhs, rlen);
  61                 }
  62         }
  63
  64         llen = (rhs ? (size_t)(rhs - lhs - 1) : strlen(lhs));
  65         if (1 <= llen && memchr(lhs, '*', llen)) {
  66                 if ((rhs && !is_glob) || (!rhs && is_fetch))
  67                         goto invalid;
  68                 is_glob = 1;
  69         } else if (rhs && is_glob)
  70                 goto invalid;
  71
  72         refspec->pattern = is_glob;
  73         refspec->src = git__strndup(lhs, llen);
  74         flags = GIT_REFERENCE_FORMAT_ALLOW_ONELEVEL |
  75                 GIT_REFERENCE_FORMAT_REFSPEC_SHORTHAND |
  76                 (is_glob ? GIT_REFERENCE_FORMAT_REFSPEC_PATTERN : 0);
  77
  78         if (is_fetch) {
  79                 /*
  80                  * LHS
  81                  * - empty is allowed; it means HEAD.
  82                  * - otherwise it must be a valid looking ref.
  83                  */
  84                 if (!*refspec->src)
  85                         ; /* empty is ok */
  86                 else if (git_reference__name_is_valid(&valid, refspec->src, flags) < 0)
  87                         goto on_error;
  88                 else if (!valid)
  89                         goto invalid;
  90
  91                 /*
  92                  * RHS
  93                  * - missing is ok, and is same as empty.
  94                  * - empty is ok; it means not to store.
  95                  * - otherwise it must be a valid looking ref.
  96                  */
  97                 if (!refspec->dst)
  98                         ; /* ok */
  99                 else if (!*refspec->dst)
 100                         ; /* ok */
 101                 else if (git_reference__name_is_valid(&valid, refspec->dst, flags) < 0)
 102                         goto on_error;
 103                 else if (!valid)
 104                         goto invalid;
 105         } else {
 106                 /*
 107                  * LHS
 108                  * - empty is allowed; it means delete.
 109                  * - when wildcarded, it must be a valid looking ref.
 110                  * - otherwise, it must be an extended SHA-1, but
 111                  *   there is no existing way to validate this.
 112                  */
 113                 if (!*refspec->src)
 114                         ; /* empty is ok */
 115                 else if (is_glob) {
 116                         if (git_reference__name_is_valid(&valid, refspec->src, flags) < 0)
 117                                 goto on_error;
 118                         else if (!valid)
 119                                 goto invalid;
 120                 }
 121                 else {
 122                         ; /* anything goes, for now */
 123                 }
 124
 125                 /*
 126                  * RHS
 127                  * - missing is allowed, but LHS then must be a
 128                  *   valid looking ref.
 129                  * - empty is not allowed.
 130                  * - otherwise it must be a valid looking ref.
 131                  */
 132                 if (!refspec->dst) {
 133                         if (git_reference__name_is_valid(&valid, refspec->src, flags) < 0)
 134                                 goto on_error;
 135                         else if (!valid)
 136                                 goto invalid;
 137                 } else if (!*refspec->dst) {
 138                         goto invalid;
 139                 } else {
 140                         if (git_reference__name_is_valid(&valid, refspec->dst, flags) < 0)
 141                                 goto on_error;
 142                         else if (!valid)
 143                                 goto invalid;
 144                 }
 145
 146                 /* if the RHS is empty, then it's a copy of the LHS */
 147                 if (!refspec->dst) {
 148                         refspec->dst = git__strdup(refspec->src);
 149                         GIT_ERROR_CHECK_ALLOC(refspec->dst);
 150                 }
 151         }
 152
 153         refspec->string = git__strdup(input);
 154         GIT_ERROR_CHECK_ALLOC(refspec->string);
 155
 156         return 0;
 157
 158 invalid:
 159         git_error_set(GIT_ERROR_INVALID,
 160                       "'%s' is not a valid refspec.", input);
 161         git_refspec__dispose(refspec);
 162         return GIT_EINVALIDSPEC;
 163
 164 on_error:
 165         git_refspec__dispose(refspec);
 166         return -1;
 167 }
 168
 169 void git_refspec__dispose(git_refspec *refspec)
 170 {
 171         if (refspec == NULL)
 172                 return;
 173
 174         git__free(refspec->src);
 175         git__free(refspec->dst);
 176         git__free(refspec->string);
 177
 178         memset(refspec, 0x0, sizeof(git_refspec));
 179 }
 180
 181 int git_refspec_parse(git_refspec **out_refspec, const char *input, int is_fetch)
 182 {
 183         git_refspec *refspec;
 184         GIT_ASSERT_ARG(out_refspec);
 185         GIT_ASSERT_ARG(input);
 186
 187         *out_refspec = NULL;
 188
 189         refspec = git__malloc(sizeof(git_refspec));
 190         GIT_ERROR_CHECK_ALLOC(refspec);
 191
 192         if (git_refspec__parse(refspec, input, !!is_fetch) != 0) {
 193                 git__free(refspec);
 194                 return -1;
 195         }
 196
 197         *out_refspec = refspec;
 198         return 0;
 199 }
 200
 201 void git_refspec_free(git_refspec *refspec)
 202 {
 203         git_refspec__dispose(refspec);
 204         git__free(refspec);
 205 }
 206
 207 const char *git_refspec_src(const git_refspec *refspec)
 208 {
 209         return refspec == NULL ? NULL : refspec->src;
 210 }
 211
 212 const char *git_refspec_dst(const git_refspec *refspec)
 213 {
 214         return refspec == NULL ? NULL : refspec->dst;
 215 }
 216
 217 const char *git_refspec_string(const git_refspec *refspec)
 218 {
 219         return refspec == NULL ? NULL : refspec->string;
 220 }
 221
 222 int git_refspec_force(const git_refspec *refspec)
 223 {
 224         GIT_ASSERT_ARG(refspec);
 225
 226         return refspec->force;
 227 }
 228
 229 int git_refspec_src_matches(const git_refspec *refspec, const char *refname)
 230 {
 231         if (refspec == NULL || refspec->src == NULL)
 232                 return false;
 233
 234         return (wildmatch(refspec->src, refname, 0) == 0);
 235 }
 236
 237 int git_refspec_dst_matches(const git_refspec *refspec, const char *refname)
 238 {
 239         if (refspec == NULL || refspec->dst == NULL)
 240                 return false;
 241
 242         return (wildmatch(refspec->dst, refname, 0) == 0);
 243 }
 244
 245 static int refspec_transform(
 246         git_buf *out, const char *from, const char *to, const char *name)
 247 {
 248         const char *from_star, *to_star;
 249         size_t replacement_len, star_offset;
 250         int error;
 251
 252         if ((error = git_buf_sanitize(out)) < 0)
 253                 return error;
 254
 255         git_buf_clear(out);
 256
 257         /*
 258          * There are two parts to each side of a refspec, the bit
 259          * before the star and the bit after it. The star can be in
 260          * the middle of the pattern, so we need to look at each bit
 261          * individually.
 262          */
 263         from_star = strchr(from, '*');
 264         to_star = strchr(to, '*');
 265
 266         GIT_ASSERT(from_star && to_star);
 267
 268         /* star offset, both in 'from' and in 'name' */
 269         star_offset = from_star - from;
 270
 271         /* the first half is copied over */
 272         git_buf_put(out, to, to_star - to);
 273
 274         /*
 275          * Copy over the name, but exclude the trailing part in "from" starting
 276          * after the glob
 277          */
 278         replacement_len = strlen(name + star_offset) - strlen(from_star + 1);
 279         git_buf_put(out, name + star_offset, replacement_len);
 280
 281         return git_buf_puts(out, to_star + 1);
 282 }
 283
 284 int git_refspec_transform(git_buf *out, const git_refspec *spec, const char *name)
 285 {
 286         int error;
 287
 288         GIT_ASSERT_ARG(out);
 289         GIT_ASSERT_ARG(spec);
 290         GIT_ASSERT_ARG(name);
 291
 292         if ((error = git_buf_sanitize(out)) < 0)
 293                 return error;
 294
 295         if (!git_refspec_src_matches(spec, name)) {
 296                 git_error_set(GIT_ERROR_INVALID, "ref '%s' doesn't match the source", name);
 297                 return -1;
 298         }
 299
 300         if (!spec->pattern)
 301                 return git_buf_puts(out, spec->dst ? spec->dst : "");
 302
 303         return refspec_transform(out, spec->src, spec->dst, name);
 304 }
 305
 306 int git_refspec_rtransform(git_buf *out, const git_refspec *spec, const char *name)
 307 {
 308         int error;
 309
 310         GIT_ASSERT_ARG(out);
 311         GIT_ASSERT_ARG(spec);
 312         GIT_ASSERT_ARG(name);
 313
 314         if ((error = git_buf_sanitize(out)) < 0)
 315                 return error;
 316
 317         if (!git_refspec_dst_matches(spec, name)) {
 318                 git_error_set(GIT_ERROR_INVALID, "ref '%s' doesn't match the destination", name);
 319                 return -1;
 320         }
 321
 322         if (!spec->pattern)
 323                 return git_buf_puts(out, spec->src);
 324
 325         return refspec_transform(out, spec->dst, spec->src, name);
 326 }
 327
 328 int git_refspec__serialize(git_buf *out, const git_refspec *refspec)
 329 {
 330         if (refspec->force)
 331                 git_buf_putc(out, '+');
 332
 333         git_buf_printf(out, "%s:%s",
 334                 refspec->src != NULL ? refspec->src : "",
 335                 refspec->dst != NULL ? refspec->dst : "");
 336
 337         return git_buf_oom(out) == false;
 338 }
 339
 340 int git_refspec_is_wildcard(const git_refspec *spec)
 341 {
 342         GIT_ASSERT_ARG(spec);
 343         GIT_ASSERT_ARG(spec->src);
 344
 345         return (spec->src[strlen(spec->src) - 1] == '*');
 346 }
 347
 348 git_direction git_refspec_direction(const git_refspec *spec)
 349 {
 350         GIT_ASSERT_ARG(spec);
 351
 352         return spec->push;
 353 }
 354
 355 int git_refspec__dwim_one(git_vector *out, git_refspec *spec, git_vector *refs)
 356 {
 357         git_buf buf = GIT_BUF_INIT;
 358         size_t j, pos;
 359         git_remote_head key;
 360         git_refspec *cur;
 361
 362         const char *formatters[] = {
 363                 GIT_REFS_DIR "%s",
 364                 GIT_REFS_TAGS_DIR "%s",
 365                 GIT_REFS_HEADS_DIR "%s",
 366                 NULL
 367         };
 368
 369         GIT_ASSERT_ARG(out);
 370         GIT_ASSERT_ARG(spec);
 371         GIT_ASSERT_ARG(refs);
 372
 373         cur = git__calloc(1, sizeof(git_refspec));
 374         GIT_ERROR_CHECK_ALLOC(cur);
 375
 376         cur->force = spec->force;
 377         cur->push = spec->push;
 378         cur->pattern = spec->pattern;
 379         cur->matching = spec->matching;
 380         cur->string = git__strdup(spec->string);
 381
 382         /* shorthand on the lhs */
 383         if (git__prefixcmp(spec->src, GIT_REFS_DIR)) {
 384                 for (j = 0; formatters[j]; j++) {
 385                         git_buf_clear(&buf);
 386                         git_buf_printf(&buf, formatters[j], spec->src);
 387                         GIT_ERROR_CHECK_ALLOC_BUF(&buf);
 388
 389                         key.name = (char *) git_buf_cstr(&buf);
 390                         if (!git_vector_search(&pos, refs, &key)) {
 391                                 /* we found something to match the shorthand, set src to that */
 392                                 cur->src = git_buf_detach(&buf);
 393                         }
 394                 }
 395         }
 396
 397         /* No shorthands found, copy over the name */
 398         if (cur->src == NULL && spec->src != NULL) {
 399                 cur->src = git__strdup(spec->src);
 400                 GIT_ERROR_CHECK_ALLOC(cur->src);
 401         }
 402
 403         if (spec->dst && git__prefixcmp(spec->dst, GIT_REFS_DIR)) {
 404                 /* if it starts with "remotes" then we just prepend "refs/" */
 405                 if (!git__prefixcmp(spec->dst, "remotes/")) {
 406                         git_buf_puts(&buf, GIT_REFS_DIR);
 407                 } else {
 408                         git_buf_puts(&buf, GIT_REFS_HEADS_DIR);
 409                 }
 410
 411                 git_buf_puts(&buf, spec->dst);
 412                 GIT_ERROR_CHECK_ALLOC_BUF(&buf);
 413
 414                 cur->dst = git_buf_detach(&buf);
 415         }
 416
 417         git_buf_dispose(&buf);
 418
 419         if (cur->dst == NULL && spec->dst != NULL) {
 420                 cur->dst = git__strdup(spec->dst);
 421                 GIT_ERROR_CHECK_ALLOC(cur->dst);
 422         }
 423
 424         return git_vector_insert(out, cur);
 425 }