1 7b19e0f1 2017-11-05 stsp /*
  2 8eea5a5c 2018-03-10 stsp  * Copyright (c) 2018 Stefan Sperling <stsp@openbsd.org>
  3 7b19e0f1 2017-11-05 stsp  *
  4 7b19e0f1 2017-11-05 stsp  * Permission to use, copy, modify, and distribute this software for any
  5 7b19e0f1 2017-11-05 stsp  * purpose with or without fee is hereby granted, provided that the above
  6 7b19e0f1 2017-11-05 stsp  * copyright notice and this permission notice appear in all copies.
  7 7b19e0f1 2017-11-05 stsp  *
  8 7b19e0f1 2017-11-05 stsp  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
  9 7b19e0f1 2017-11-05 stsp  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 10 7b19e0f1 2017-11-05 stsp  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 11 7b19e0f1 2017-11-05 stsp  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 12 7b19e0f1 2017-11-05 stsp  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 13 7b19e0f1 2017-11-05 stsp  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 14 7b19e0f1 2017-11-05 stsp  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 15 7b19e0f1 2017-11-05 stsp  */
 16 7b19e0f1 2017-11-05 stsp 
 17 4027f31a 2017-11-04 stsp #include <sys/types.h>
 18 d1cda826 2017-11-06 stsp #include <sys/queue.h>
 19 d1cda826 2017-11-06 stsp 
 20 4027f31a 2017-11-04 stsp #include <sha1.h>
 21 4027f31a 2017-11-04 stsp #include <stdio.h>
 22 4027f31a 2017-11-04 stsp #include <stdlib.h>
 23 4027f31a 2017-11-04 stsp #include <string.h>
 24 4027f31a 2017-11-04 stsp #include <util.h>
 25 68482ea3 2017-11-27 stsp #include <zlib.h>
 26 4027f31a 2017-11-04 stsp 
 27 4027f31a 2017-11-04 stsp #include "got_error.h"
 28 11995603 2017-11-05 stsp #include "got_object.h"
 29 11995603 2017-11-05 stsp #include "got_repository.h"
 30 4027f31a 2017-11-04 stsp #include "got_refs.h"
 31 4027f31a 2017-11-04 stsp 
 32 718b3ab0 2018-03-17 stsp #include "got_lib_sha1.h"
 33 718b3ab0 2018-03-17 stsp #include "got_lib_path.h"
 34 718b3ab0 2018-03-17 stsp #include "got_lib_delta.h"
 35 718b3ab0 2018-03-17 stsp #include "got_lib_zbuf.h"
 36 718b3ab0 2018-03-17 stsp #include "got_lib_object.h"
 37 38d42f42 2018-02-12 stsp 
 38 38d42f42 2018-02-12 stsp /* A symbolic reference. */
 39 38d42f42 2018-02-12 stsp struct got_symref {
 40 38d42f42 2018-02-12 stsp 	char *name;
 41 38d42f42 2018-02-12 stsp 	char *ref;
 42 38d42f42 2018-02-12 stsp };
 43 38d42f42 2018-02-12 stsp 
 44 38d42f42 2018-02-12 stsp /* A non-symbolic reference (there is no better designation). */
 45 38d42f42 2018-02-12 stsp struct got_ref {
 46 38d42f42 2018-02-12 stsp 	char *name;
 47 38d42f42 2018-02-12 stsp 	u_int8_t sha1[SHA1_DIGEST_LENGTH];
 48 38d42f42 2018-02-12 stsp };
 49 c3f94f68 2017-11-05 stsp 
 50 38d42f42 2018-02-12 stsp /* A reference which points to an arbitrary object. */
 51 38d42f42 2018-02-12 stsp struct got_reference {
 52 38d42f42 2018-02-12 stsp 	unsigned int flags;
 53 38d42f42 2018-02-12 stsp #define GOT_REF_IS_SYMBOLIC	0x01
 54 38d42f42 2018-02-12 stsp 
 55 38d42f42 2018-02-12 stsp 	union {
 56 38d42f42 2018-02-12 stsp 		struct got_ref ref;
 57 38d42f42 2018-02-12 stsp 		struct got_symref symref;
 58 38d42f42 2018-02-12 stsp 	} ref;
 59 38d42f42 2018-02-12 stsp };
 60 38d42f42 2018-02-12 stsp 
 61 4027f31a 2017-11-04 stsp static const struct got_error *
 62 4027f31a 2017-11-04 stsp parse_symref(struct got_reference **ref, const char *name, const char *line)
 63 4027f31a 2017-11-04 stsp {
 64 4027f31a 2017-11-04 stsp 	struct got_symref *symref;
 65 4027f31a 2017-11-04 stsp 	char *symref_name;
 66 4027f31a 2017-11-04 stsp 	char *symref_ref;
 67 4027f31a 2017-11-04 stsp 
 68 4027f31a 2017-11-04 stsp 	if (line[0] == '\0')
 69 4027f31a 2017-11-04 stsp 		return got_error(GOT_ERR_NOT_REF);
 70 4027f31a 2017-11-04 stsp 
 71 4027f31a 2017-11-04 stsp 	symref_name = strdup(name);
 72 4027f31a 2017-11-04 stsp 	if (symref_name == NULL)
 73 0a585a0d 2018-03-17 stsp 		return got_error_from_errno();
 74 4027f31a 2017-11-04 stsp 	symref_ref = strdup(line);
 75 4027f31a 2017-11-04 stsp 	if (symref_ref == NULL) {
 76 0a585a0d 2018-03-17 stsp 		const struct got_error *err = got_error_from_errno();
 77 4027f31a 2017-11-04 stsp 		free(symref_name);
 78 0a585a0d 2018-03-17 stsp 		return err;
 79 4027f31a 2017-11-04 stsp 	}
 80 4027f31a 2017-11-04 stsp 
 81 4027f31a 2017-11-04 stsp 	*ref = calloc(1, sizeof(**ref));
 82 1db76ab5 2018-01-26 mpi 	if (*ref == NULL)
 83 0a585a0d 2018-03-17 stsp 		return got_error_from_errno();
 84 4027f31a 2017-11-04 stsp 	(*ref)->flags |= GOT_REF_IS_SYMBOLIC;
 85 4027f31a 2017-11-04 stsp 	symref = &((*ref)->ref.symref);
 86 4027f31a 2017-11-04 stsp 	symref->name = symref_name;
 87 4027f31a 2017-11-04 stsp 	symref->ref = symref_ref;
 88 4027f31a 2017-11-04 stsp 	return NULL;
 89 4027f31a 2017-11-04 stsp }
 90 4027f31a 2017-11-04 stsp 
 91 4027f31a 2017-11-04 stsp static const struct got_error *
 92 4027f31a 2017-11-04 stsp parse_ref_line(struct got_reference **ref, const char *name, const char *line)
 93 4027f31a 2017-11-04 stsp {
 94 4027f31a 2017-11-04 stsp 	uint8_t digest[SHA1_DIGEST_LENGTH];
 95 4027f31a 2017-11-04 stsp 	char *ref_name;
 96 4027f31a 2017-11-04 stsp 
 97 4027f31a 2017-11-04 stsp 	if (strncmp(line, "ref: ", 5) == 0) {
 98 4027f31a 2017-11-04 stsp 		line += 5;
 99 4027f31a 2017-11-04 stsp 		return parse_symref(ref, name, line);
100 4027f31a 2017-11-04 stsp 	}
101 4027f31a 2017-11-04 stsp 
102 4027f31a 2017-11-04 stsp 	ref_name = strdup(name);
103 4027f31a 2017-11-04 stsp 	if (ref_name == NULL)
104 0a585a0d 2018-03-17 stsp 		return got_error_from_errno();
105 4027f31a 2017-11-04 stsp 
106 d1cda826 2017-11-06 stsp 	if (!got_parse_sha1_digest(digest, line))
107 4027f31a 2017-11-04 stsp 		return got_error(GOT_ERR_NOT_REF);
108 4027f31a 2017-11-04 stsp 
109 4027f31a 2017-11-04 stsp 	*ref = calloc(1, sizeof(**ref));
110 1db76ab5 2018-01-26 mpi 	if (*ref == NULL)
111 0a585a0d 2018-03-17 stsp 		return got_error_from_errno();
112 4027f31a 2017-11-04 stsp 	(*ref)->ref.ref.name = ref_name;
113 4027f31a 2017-11-04 stsp 	memcpy(&(*ref)->ref.ref.sha1, digest, SHA1_DIGEST_LENGTH);
114 4027f31a 2017-11-04 stsp 	return NULL;
115 4027f31a 2017-11-04 stsp }
116 4027f31a 2017-11-04 stsp 
117 4027f31a 2017-11-04 stsp static const struct got_error *
118 4027f31a 2017-11-04 stsp parse_ref_file(struct got_reference **ref, const char *name,
119 4027f31a 2017-11-04 stsp     const char *abspath)
120 4027f31a 2017-11-04 stsp {
121 4027f31a 2017-11-04 stsp 	const struct got_error *err = NULL;
122 4027f31a 2017-11-04 stsp 	FILE *f = fopen(abspath, "rb");
123 4027f31a 2017-11-04 stsp 	char *line;
124 4027f31a 2017-11-04 stsp 	size_t len;
125 4027f31a 2017-11-04 stsp 	const char delim[3] = {'\0', '\0', '\0'};
126 4027f31a 2017-11-04 stsp 
127 4027f31a 2017-11-04 stsp 	if (f == NULL)
128 4027f31a 2017-11-04 stsp 		return got_error(GOT_ERR_NOT_REF);
129 4027f31a 2017-11-04 stsp 
130 4027f31a 2017-11-04 stsp 	line = fparseln(f, &len, NULL, delim, 0);
131 4027f31a 2017-11-04 stsp 	if (line == NULL) {
132 4027f31a 2017-11-04 stsp 		err = got_error(GOT_ERR_NOT_REF);
133 4027f31a 2017-11-04 stsp 		goto done;
134 4027f31a 2017-11-04 stsp 	}
135 4027f31a 2017-11-04 stsp 
136 4027f31a 2017-11-04 stsp 	err = parse_ref_line(ref, name, line);
137 4027f31a 2017-11-04 stsp done:
138 4027f31a 2017-11-04 stsp 	free(line);
139 4027f31a 2017-11-04 stsp 	fclose(f);
140 4027f31a 2017-11-04 stsp 	return err;
141 4027f31a 2017-11-04 stsp }
142 4027f31a 2017-11-04 stsp 
143 11995603 2017-11-05 stsp static char *
144 11995603 2017-11-05 stsp get_refs_dir_path(struct got_repository *repo, const char *refname)
145 11995603 2017-11-05 stsp {
146 11995603 2017-11-05 stsp 	if (strcmp(refname, GOT_REF_HEAD) == 0 ||
147 11995603 2017-11-05 stsp 	    strcmp(refname, GOT_REF_ORIG_HEAD) == 0 ||
148 11995603 2017-11-05 stsp 	    strcmp(refname, GOT_REF_MERGE_HEAD) == 0 ||
149 d4a5a885 2017-11-05 stsp 	    strcmp(refname, GOT_REF_FETCH_HEAD) == 0 ||
150 d4a5a885 2017-11-05 stsp 	    strncmp(refname, "refs/", 5) == 0)
151 11995603 2017-11-05 stsp 		return got_repo_get_path_git_dir(repo);
152 11995603 2017-11-05 stsp 
153 11995603 2017-11-05 stsp 	return got_repo_get_path_refs(repo);
154 11995603 2017-11-05 stsp }
155 11995603 2017-11-05 stsp 
156 4027f31a 2017-11-04 stsp const struct got_error *
157 11995603 2017-11-05 stsp got_ref_open(struct got_reference **ref, struct got_repository *repo,
158 4027f31a 2017-11-04 stsp    const char *refname)
159 4027f31a 2017-11-04 stsp {
160 4027f31a 2017-11-04 stsp 	const struct got_error *err = NULL;
161 4027f31a 2017-11-04 stsp 	char *path_ref = NULL;
162 4027f31a 2017-11-04 stsp 	char *normpath = NULL;
163 11995603 2017-11-05 stsp 	char *path_refs = get_refs_dir_path(repo, refname);
164 11995603 2017-11-05 stsp 
165 11995603 2017-11-05 stsp 	if (path_refs == NULL) {
166 0a585a0d 2018-03-17 stsp 		err = got_error_from_errno();
167 11995603 2017-11-05 stsp 		goto done;
168 11995603 2017-11-05 stsp 	}
169 4027f31a 2017-11-04 stsp 	
170 4027f31a 2017-11-04 stsp 	/* XXX For now, this assumes that refs exist in the filesystem. */
171 4027f31a 2017-11-04 stsp 
172 4027f31a 2017-11-04 stsp 	if (asprintf(&path_ref, "%s/%s", path_refs, refname) == -1) {
173 0a585a0d 2018-03-17 stsp 		err = got_error_from_errno();
174 4027f31a 2017-11-04 stsp 		goto done;
175 4027f31a 2017-11-04 stsp 	}
176 4027f31a 2017-11-04 stsp 
177 4027f31a 2017-11-04 stsp 	normpath = got_path_normalize(path_ref);
178 4027f31a 2017-11-04 stsp 	if (normpath == NULL) {
179 4027f31a 2017-11-04 stsp 		err = got_error(GOT_ERR_NOT_REF);
180 4027f31a 2017-11-04 stsp 		goto done;
181 4027f31a 2017-11-04 stsp 	}
182 4027f31a 2017-11-04 stsp 
183 11995603 2017-11-05 stsp 	err = parse_ref_file(ref, refname, normpath);
184 4027f31a 2017-11-04 stsp done:
185 4027f31a 2017-11-04 stsp 	free(normpath);
186 4027f31a 2017-11-04 stsp 	free(path_ref);
187 11995603 2017-11-05 stsp 	free(path_refs);
188 4027f31a 2017-11-04 stsp 	return err;
189 4027f31a 2017-11-04 stsp }
190 4027f31a 2017-11-04 stsp 
191 4027f31a 2017-11-04 stsp void
192 4027f31a 2017-11-04 stsp got_ref_close(struct got_reference *ref)
193 4027f31a 2017-11-04 stsp {
194 4027f31a 2017-11-04 stsp 	if (ref->flags & GOT_REF_IS_SYMBOLIC)
195 4027f31a 2017-11-04 stsp 		free(ref->ref.symref.name);
196 4027f31a 2017-11-04 stsp 	else
197 4027f31a 2017-11-04 stsp 		free(ref->ref.ref.name);
198 4027f31a 2017-11-04 stsp 	free(ref);
199 4027f31a 2017-11-04 stsp }
200 11995603 2017-11-05 stsp 
201 11995603 2017-11-05 stsp struct got_reference *
202 11995603 2017-11-05 stsp got_ref_dup(struct got_reference *ref)
203 11995603 2017-11-05 stsp {
204 1db76ab5 2018-01-26 mpi 	struct got_reference *ret;
205 11995603 2017-11-05 stsp 
206 1db76ab5 2018-01-26 mpi 	ret = calloc(1, sizeof(*ret));
207 11995603 2017-11-05 stsp 	if (ret == NULL)
208 11995603 2017-11-05 stsp 		return NULL;
209 11995603 2017-11-05 stsp 
210 11995603 2017-11-05 stsp 	ret->flags = ref->flags;
211 11995603 2017-11-05 stsp 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
212 11995603 2017-11-05 stsp 		ret->ref.symref.name = strdup(ref->ref.symref.name);
213 11995603 2017-11-05 stsp 		if (ret->ref.symref.name == NULL) {
214 11995603 2017-11-05 stsp 			free(ret);
215 11995603 2017-11-05 stsp 			return NULL;
216 11995603 2017-11-05 stsp 		}
217 11995603 2017-11-05 stsp 		ret->ref.symref.ref = strdup(ref->ref.symref.ref);
218 11995603 2017-11-05 stsp 		if (ret->ref.symref.ref == NULL) {
219 11995603 2017-11-05 stsp 			free(ret->ref.symref.name);
220 11995603 2017-11-05 stsp 			free(ret);
221 11995603 2017-11-05 stsp 			return NULL;
222 11995603 2017-11-05 stsp 		}
223 11995603 2017-11-05 stsp 	} else {
224 11995603 2017-11-05 stsp 		ref->ref.ref.name = strdup(ref->ref.ref.name);
225 11995603 2017-11-05 stsp 		if (ref->ref.ref.name == NULL) {
226 11995603 2017-11-05 stsp 			free(ret);
227 11995603 2017-11-05 stsp 			return NULL;
228 11995603 2017-11-05 stsp 		}
229 11995603 2017-11-05 stsp 		memcpy(ret->ref.ref.sha1, ref->ref.ref.sha1,
230 11995603 2017-11-05 stsp 		    SHA1_DIGEST_LENGTH);
231 11995603 2017-11-05 stsp 	}
232 11995603 2017-11-05 stsp 
233 11995603 2017-11-05 stsp 	return ret;
234 11995603 2017-11-05 stsp }
235 11995603 2017-11-05 stsp 
236 11995603 2017-11-05 stsp static const struct got_error *
237 11995603 2017-11-05 stsp resolve_symbolic_ref(struct got_reference **resolved,
238 11995603 2017-11-05 stsp     struct got_repository *repo, struct got_reference *ref)
239 11995603 2017-11-05 stsp {
240 11995603 2017-11-05 stsp 	struct got_reference *nextref;
241 11995603 2017-11-05 stsp 	const struct got_error *err;
242 11995603 2017-11-05 stsp 
243 11995603 2017-11-05 stsp 	err = got_ref_open(&nextref, repo, ref->ref.symref.ref);
244 11995603 2017-11-05 stsp 	if (err)
245 11995603 2017-11-05 stsp 		return err;
246 11995603 2017-11-05 stsp 
247 11995603 2017-11-05 stsp 	if (nextref->flags & GOT_REF_IS_SYMBOLIC)
248 11995603 2017-11-05 stsp 		err = resolve_symbolic_ref(resolved, repo, nextref);
249 11995603 2017-11-05 stsp 	else
250 11995603 2017-11-05 stsp 		*resolved = got_ref_dup(nextref);
251 11995603 2017-11-05 stsp 
252 11995603 2017-11-05 stsp 	got_ref_close(nextref);
253 11995603 2017-11-05 stsp 	return err;
254 11995603 2017-11-05 stsp }
255 11995603 2017-11-05 stsp 
256 11995603 2017-11-05 stsp const struct got_error *
257 11995603 2017-11-05 stsp got_ref_resolve(struct got_object_id **id, struct got_repository *repo,
258 11995603 2017-11-05 stsp     struct got_reference *ref)
259 11995603 2017-11-05 stsp {
260 11995603 2017-11-05 stsp 	const struct got_error *err;
261 11995603 2017-11-05 stsp 
262 11995603 2017-11-05 stsp 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
263 11995603 2017-11-05 stsp 		struct got_reference *resolved = NULL;
264 11995603 2017-11-05 stsp 		err = resolve_symbolic_ref(&resolved, repo, ref);
265 11995603 2017-11-05 stsp 		if (err == NULL)
266 11995603 2017-11-05 stsp 			err = got_ref_resolve(id, repo, resolved);
267 11995603 2017-11-05 stsp 		free(resolved);
268 11995603 2017-11-05 stsp 		return err;
269 11995603 2017-11-05 stsp 	}
270 11995603 2017-11-05 stsp 
271 11995603 2017-11-05 stsp 	*id = calloc(1, sizeof(**id));
272 11995603 2017-11-05 stsp 	if (*id == NULL)
273 0a585a0d 2018-03-17 stsp 		return got_error_from_errno();
274 11995603 2017-11-05 stsp 	memcpy((*id)->sha1, ref->ref.ref.sha1, SHA1_DIGEST_LENGTH);
275 11995603 2017-11-05 stsp 	return NULL;
276 86c3caaf 2018-03-09 stsp }
277 86c3caaf 2018-03-09 stsp 
278 86c3caaf 2018-03-09 stsp char *
279 86c3caaf 2018-03-09 stsp got_ref_to_str(struct got_reference *ref)
280 86c3caaf 2018-03-09 stsp {
281 86c3caaf 2018-03-09 stsp 	char *str;
282 86c3caaf 2018-03-09 stsp 	if (ref->flags & GOT_REF_IS_SYMBOLIC) {
283 86c3caaf 2018-03-09 stsp 		if (asprintf(&str, "ref: %s", ref->ref.symref.ref) == -1)
284 86c3caaf 2018-03-09 stsp 			return NULL;
285 86c3caaf 2018-03-09 stsp 	} else {
286 86c3caaf 2018-03-09 stsp 		str = calloc(1, SHA1_DIGEST_STRING_LENGTH);
287 86c3caaf 2018-03-09 stsp 		if (str == NULL)
288 86c3caaf 2018-03-09 stsp 			return NULL;
289 86c3caaf 2018-03-09 stsp 		str = got_sha1_digest_to_str(ref->ref.ref.sha1, str,
290 86c3caaf 2018-03-09 stsp 		    SHA1_DIGEST_STRING_LENGTH);
291 86c3caaf 2018-03-09 stsp 	}
292 86c3caaf 2018-03-09 stsp 
293 86c3caaf 2018-03-09 stsp 	return str;
294 11995603 2017-11-05 stsp }