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