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 "git2/errors.h"
   9
  10 #include "common.h"
  11 #include "refspec.h"
  12 #include "util.h"
  13 #include "posix.h"
  14 #include "refs.h"
  15 #include "vector.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 flags;
  25
  26         assert(refspec && input);
  27
  28         memset(refspec, 0x0, sizeof(git_refspec));
  29         refspec->push = !is_fetch;
  30
  31         lhs = input;
  32         if (*lhs == '+') {
  33                 refspec->force = 1;
  34                 lhs++;
  35         }
  36
  37         rhs = strrchr(lhs, ':');
  38
  39         /*
  40          * Before going on, special case ":" (or "+:") as a refspec
  41          * for matching refs.
  42          */
  43         if (!is_fetch && rhs == lhs && rhs[1] == '\0') {
  44                 refspec->matching = 1;
  45                 refspec->string = git__strdup(input);
  46                 GITERR_CHECK_ALLOC(refspec->string);
  47                 refspec->src = git__strdup("");
  48                 GITERR_CHECK_ALLOC(refspec->src);
  49                 refspec->dst = git__strdup("");
  50                 GITERR_CHECK_ALLOC(refspec->dst);
  51                 return 0;
  52         }
  53
  54         if (rhs) {
  55                 size_t rlen = strlen(++rhs);
  56                 if (rlen || !is_fetch) {
  57                         is_glob = (1 <= rlen && strchr(rhs, '*'));
  58                         refspec->dst = git__strndup(rhs, rlen);
  59                 }
  60         }
  61
  62         llen = (rhs ? (size_t)(rhs - lhs - 1) : strlen(lhs));
  63         if (1 <= llen && memchr(lhs, '*', llen)) {
  64                 if ((rhs && !is_glob) || (!rhs && is_fetch))
  65                         goto invalid;
  66                 is_glob = 1;
  67         } else if (rhs && is_glob)
  68                 goto invalid;
  69
  70         refspec->pattern = is_glob;
  71         refspec->src = git__strndup(lhs, llen);
  72         flags = GIT_REF_FORMAT_ALLOW_ONELEVEL | GIT_REF_FORMAT_REFSPEC_SHORTHAND
  73                 | (is_glob ? GIT_REF_FORMAT_REFSPEC_PATTERN : 0);
  74
  75         if (is_fetch) {
  76                 /*
  77                         * LHS
  78                         * - empty is allowed; it means HEAD.
  79                         * - otherwise it must be a valid looking ref.
  80                         */
  81                 if (!*refspec->src)
  82                         ; /* empty is ok */
  83                 else if (!git_reference__is_valid_name(refspec->src, flags))
  84                         goto invalid;
  85                 /*
  86                         * RHS
  87                         * - missing is ok, and is same as empty.
  88                         * - empty is ok; it means not to store.
  89                         * - otherwise it must be a valid looking ref.
  90                         */
  91                 if (!refspec->dst)
  92                         ; /* ok */
  93                 else if (!*refspec->dst)
  94                         ; /* ok */
  95                 else if (!git_reference__is_valid_name(refspec->dst, flags))
  96                         goto invalid;
  97         } else {
  98                 /*
  99                         * LHS
 100                         * - empty is allowed; it means delete.
 101                         * - when wildcarded, it must be a valid looking ref.
 102                         * - otherwise, it must be an extended SHA-1, but
 103                         *   there is no existing way to validate this.
 104                         */
 105                 if (!*refspec->src)
 106                         ; /* empty is ok */
 107                 else if (is_glob) {
 108                         if (!git_reference__is_valid_name(refspec->src, flags))
 109                                 goto invalid;
 110                 }
 111                 else {
 112                         ; /* anything goes, for now */
 113                 }
 114                 /*
 115                         * RHS
 116                         * - missing is allowed, but LHS then must be a
 117                         *   valid looking ref.
 118                         * - empty is not allowed.
 119                         * - otherwise it must be a valid looking ref.
 120                         */
 121                 if (!refspec->dst) {
 122                         if (!git_reference__is_valid_name(refspec->src, flags))
 123                                 goto invalid;
 124                 } else if (!*refspec->dst) {
 125                         goto invalid;
 126                 } else {
 127                         if (!git_reference__is_valid_name(refspec->dst, flags))
 128                                 goto invalid;
 129                 }
 130
 131                 /* if the RHS is empty, then it's a copy of the LHS */
 132                 if (!refspec->dst) {
 133                         refspec->dst = git__strdup(refspec->src);
 134                         GITERR_CHECK_ALLOC(refspec->dst);
 135                 }
 136         }
 137
 138         refspec->string = git__strdup(input);
 139         GITERR_CHECK_ALLOC(refspec->string);
 140
 141         return 0;
 142
 143  invalid:
 144         giterr_set(
 145                 GITERR_INVALID,
 146                 "'%s' is not a valid refspec.", input);
 147         git_refspec__free(refspec);
 148         return -1;
 149 }
 150
 151 void git_refspec__free(git_refspec *refspec)
 152 {
 153         if (refspec == NULL)
 154                 return;
 155
 156         git__free(refspec->src);
 157         git__free(refspec->dst);
 158         git__free(refspec->string);
 159
 160         memset(refspec, 0x0, sizeof(git_refspec));
 161 }
 162
 163 const char *git_refspec_src(const git_refspec *refspec)
 164 {
 165         return refspec == NULL ? NULL : refspec->src;
 166 }
 167
 168 const char *git_refspec_dst(const git_refspec *refspec)
 169 {
 170         return refspec == NULL ? NULL : refspec->dst;
 171 }
 172
 173 const char *git_refspec_string(const git_refspec *refspec)
 174 {
 175         return refspec == NULL ? NULL : refspec->string;
 176 }
 177
 178 int git_refspec_force(const git_refspec *refspec)
 179 {
 180         assert(refspec);
 181
 182         return refspec->force;
 183 }
 184
 185 int git_refspec_src_matches(const git_refspec *refspec, const char *refname)
 186 {
 187         if (refspec == NULL || refspec->src == NULL)
 188                 return false;
 189
 190         return (p_fnmatch(refspec->src, refname, 0) == 0);
 191 }
 192
 193 int git_refspec_dst_matches(const git_refspec *refspec, const char *refname)
 194 {
 195         if (refspec == NULL || refspec->dst == NULL)
 196                 return false;
 197
 198         return (p_fnmatch(refspec->dst, refname, 0) == 0);
 199 }
 200
 201 static int refspec_transform(
 202         git_buf *out, const char *from, const char *to, const char *name)
 203 {
 204         const char *from_star, *to_star;
 205         const char *name_slash, *from_slash;
 206         size_t replacement_len, star_offset;
 207
 208         git_buf_sanitize(out);
 209         git_buf_clear(out);
 210
 211         /*
 212          * There are two parts to each side of a refspec, the bit
 213          * before the star and the bit after it. The star can be in
 214          * the middle of the pattern, so we need to look at each bit
 215          * individually.
 216          */
 217         from_star = strchr(from, '*');
 218         to_star = strchr(to, '*');
 219
 220         assert(from_star && to_star);
 221
 222         /* star offset, both in 'from' and in 'name' */
 223         star_offset = from_star - from;
 224
 225         /* the first half is copied over */
 226         git_buf_put(out, to, to_star - to);
 227
 228         /* then we copy over the replacement, from the star's offset to the next slash in 'name' */
 229         name_slash = strchr(name + star_offset, '/');
 230         if (!name_slash)
 231                 name_slash = strrchr(name, '\0');
 232
 233         /* if there is no slash after the star in 'from', we want to copy everything over */
 234         from_slash = strchr(from + star_offset, '/');
 235         if (!from_slash)
 236                 name_slash = strrchr(name, '\0');
 237
 238         replacement_len = (name_slash - name) - star_offset;
 239         git_buf_put(out, name + star_offset, replacement_len);
 240
 241         return git_buf_puts(out, to_star + 1);
 242 }
 243
 244 int git_refspec_transform(git_buf *out, const git_refspec *spec, const char *name)
 245 {
 246         assert(out && spec && name);
 247         git_buf_sanitize(out);
 248
 249         if (!git_refspec_src_matches(spec, name)) {
 250                 giterr_set(GITERR_INVALID, "ref '%s' doesn't match the source", name);
 251                 return -1;
 252         }
 253
 254         if (!spec->pattern)
 255                 return git_buf_puts(out, spec->dst);
 256
 257         return refspec_transform(out, spec->src, spec->dst, name);
 258 }
 259
 260 int git_refspec_rtransform(git_buf *out, const git_refspec *spec, const char *name)
 261 {
 262         assert(out && spec && name);
 263         git_buf_sanitize(out);
 264
 265         if (!git_refspec_dst_matches(spec, name)) {
 266                 giterr_set(GITERR_INVALID, "ref '%s' doesn't match the destination", name);
 267                 return -1;
 268         }
 269
 270         if (!spec->pattern)
 271                 return git_buf_puts(out, spec->src);
 272
 273         return refspec_transform(out, spec->dst, spec->src, name);
 274 }
 275
 276 int git_refspec__serialize(git_buf *out, const git_refspec *refspec)
 277 {
 278         if (refspec->force)
 279                 git_buf_putc(out, '+');
 280
 281         git_buf_printf(out, "%s:%s",
 282                 refspec->src != NULL ? refspec->src : "",
 283                 refspec->dst != NULL ? refspec->dst : "");
 284
 285         return git_buf_oom(out) == false;
 286 }
 287
 288 int git_refspec_is_wildcard(const git_refspec *spec)
 289 {
 290         assert(spec && spec->src);
 291
 292         return (spec->src[strlen(spec->src) - 1] == '*');
 293 }
 294
 295 git_direction git_refspec_direction(const git_refspec *spec)
 296 {
 297         assert(spec);
 298
 299         return spec->push;
 300 }
 301
 302 int git_refspec__dwim_one(git_vector *out, git_refspec *spec, git_vector *refs)
 303 {
 304         git_buf buf = GIT_BUF_INIT;
 305         size_t j, pos;
 306         git_remote_head key;
 307
 308         const char* formatters[] = {
 309                 GIT_REFS_DIR "%s",
 310                 GIT_REFS_TAGS_DIR "%s",
 311                 GIT_REFS_HEADS_DIR "%s",
 312                 NULL
 313         };
 314
 315         git_refspec *cur = git__calloc(1, sizeof(git_refspec));
 316         GITERR_CHECK_ALLOC(cur);
 317
 318         cur->force = spec->force;
 319         cur->push = spec->push;
 320         cur->pattern = spec->pattern;
 321         cur->matching = spec->matching;
 322         cur->string = git__strdup(spec->string);
 323
 324         /* shorthand on the lhs */
 325         if (git__prefixcmp(spec->src, GIT_REFS_DIR)) {
 326                 for (j = 0; formatters[j]; j++) {
 327                         git_buf_clear(&buf);
 328                         git_buf_printf(&buf, formatters[j], spec->src);
 329                         GITERR_CHECK_ALLOC_BUF(&buf);
 330
 331                         key.name = (char *) git_buf_cstr(&buf);
 332                         if (!git_vector_search(&pos, refs, &key)) {
 333                                 /* we found something to match the shorthand, set src to that */
 334                                 cur->src = git_buf_detach(&buf);
 335                         }
 336                 }
 337         }
 338
 339         /* No shorthands found, copy over the name */
 340         if (cur->src == NULL && spec->src != NULL) {
 341                 cur->src = git__strdup(spec->src);
 342                 GITERR_CHECK_ALLOC(cur->src);
 343         }
 344
 345         if (spec->dst && git__prefixcmp(spec->dst, GIT_REFS_DIR)) {
 346                 /* if it starts with "remotes" then we just prepend "refs/" */
 347                 if (!git__prefixcmp(spec->dst, "remotes/")) {
 348                         git_buf_puts(&buf, GIT_REFS_DIR);
 349                 } else {
 350                         git_buf_puts(&buf, GIT_REFS_HEADS_DIR);
 351                 }
 352
 353                 git_buf_puts(&buf, spec->dst);
 354                 GITERR_CHECK_ALLOC_BUF(&buf);
 355
 356                 cur->dst = git_buf_detach(&buf);
 357         }
 358
 359         git_buf_free(&buf);
 360
 361         if (cur->dst == NULL && spec->dst != NULL) {
 362                 cur->dst = git__strdup(spec->dst);
 363                 GITERR_CHECK_ALLOC(cur->dst);
 364         }
 365
 366         return git_vector_insert(out, cur);
 367 }