transaction.c 8.29 KB
Newer Older
1 2 3 4 5 6 7
/*
 * Copyright (C) the libgit2 contributors. All rights reserved.
 *
 * This file is part of libgit2, distributed under the GNU GPL v2 with
 * a Linking Exception. For full terms see the included COPYING file.
 */

8 9
#include "transaction.h"

10 11 12 13 14 15
#include "repository.h"
#include "strmap.h"
#include "refdb.h"
#include "pool.h"
#include "reflog.h"
#include "signature.h"
16
#include "config.h"
17

18
#include "git2/transaction.h"
19 20 21 22
#include "git2/signature.h"
#include "git2/sys/refs.h"
#include "git2/sys/refdb_backend.h"

23 24 25 26 27 28
typedef enum {
	TRANSACTION_NONE,
	TRANSACTION_REFS,
	TRANSACTION_CONFIG,
} transaction_t;

29 30 31 32
typedef struct {
	const char *name;
	void *payload;

33
	git_reference_t ref_type;
34 35 36 37 38 39 40 41 42 43 44 45 46 47
	union {
		git_oid id;
		char *symbolic;
	} target;
	git_reflog *reflog;

	const char *message;
	git_signature *sig;

	unsigned int committed :1,
		remove :1;
} transaction_node;

struct git_transaction {
48
	transaction_t type;
49 50
	git_repository *repo;
	git_refdb *db;
51
	git_config *cfg;
52 53 54 55 56

	git_strmap *locks;
	git_pool pool;
};

57 58 59 60 61 62
int git_transaction_config_new(git_transaction **out, git_config *cfg)
{
	git_transaction *tx;
	assert(out && cfg);

	tx = git__calloc(1, sizeof(git_transaction));
63
	GIT_ERROR_CHECK_ALLOC(tx);
64 65 66 67 68 69 70

	tx->type = TRANSACTION_CONFIG;
	tx->cfg = cfg;
	*out = tx;
	return 0;
}

71 72 73 74 75 76 77 78
int git_transaction_new(git_transaction **out, git_repository *repo)
{
	int error;
	git_pool pool;
	git_transaction *tx = NULL;

	assert(out && repo);

79 80
	if ((error = git_pool_init(&pool, 1)) < 0)
		goto on_error;
81 82 83 84 85 86 87

	tx = git_pool_mallocz(&pool, sizeof(git_transaction));
	if (!tx) {
		error = -1;
		goto on_error;
	}

88
	if ((error = git_strmap_new(&tx->locks)) < 0) {
89 90 91 92 93 94 95
		error = -1;
		goto on_error;
	}

	if ((error = git_repository_refdb(&tx->db, repo)) < 0)
		goto on_error;

96
	tx->type = TRANSACTION_REFS;
97 98 99 100 101 102 103 104 105 106
	memcpy(&tx->pool, &pool, sizeof(git_pool));
	tx->repo = repo;
	*out = tx;
	return 0;

on_error:
	git_pool_clear(&pool);
	return error;
}

107
int git_transaction_lock_ref(git_transaction *tx, const char *refname)
108 109 110 111 112 113 114
{
	int error;
	transaction_node *node;

	assert(tx && refname);

	node = git_pool_mallocz(&tx->pool, sizeof(transaction_node));
115
	GIT_ERROR_CHECK_ALLOC(node);
116 117

	node->name = git_pool_strdup(&tx->pool, refname);
118
	GIT_ERROR_CHECK_ALLOC(node->name);
119 120 121 122

	if ((error = git_refdb_lock(&node->payload, tx->db, refname)) < 0)
		return error;

123
	if ((error = git_strmap_set(tx->locks, node->name, node)) < 0)
124 125 126 127 128 129 130 131 132 133 134 135 136 137
		goto cleanup;

	return 0;

cleanup:
	git_refdb_unlock(tx->db, node->payload, false, false, NULL, NULL, NULL);

	return error;
}

static int find_locked(transaction_node **out, git_transaction *tx, const char *refname)
{
	transaction_node *node;

138
	if ((node = git_strmap_get(tx->locks, refname)) == NULL) {
139
		git_error_set(GIT_ERROR_REFERENCE, "the specified reference is not locked");
140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167
		return GIT_ENOTFOUND;
	}

	*out = node;
	return 0;
}

static int copy_common(transaction_node *node, git_transaction *tx, const git_signature *sig, const char *msg)
{
	if (sig && git_signature__pdup(&node->sig, sig, &tx->pool) < 0)
		return -1;

	if (!node->sig) {
		git_signature *tmp;
		int error;

		if (git_reference__log_signature(&tmp, tx->repo) < 0)
			return -1;

		/* make sure the sig we use is in our pool */
		error = git_signature__pdup(&node->sig, tmp, &tx->pool);
		git_signature_free(tmp);
		if (error < 0)
			return error;
	}

	if (msg) {
		node->message = git_pool_strdup(&tx->pool, msg);
168
		GIT_ERROR_CHECK_ALLOC(node->message);
169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187
	}

	return 0;
}

int git_transaction_set_target(git_transaction *tx, const char *refname, const git_oid *target, const git_signature *sig, const char *msg)
{
	int error;
	transaction_node *node;

	assert(tx && refname && target);

	if ((error = find_locked(&node, tx, refname)) < 0)
		return error;

	if ((error = copy_common(node, tx, sig, msg)) < 0)
		return error;

	git_oid_cpy(&node->target.id, target);
188
	node->ref_type = GIT_REFERENCE_DIRECT;
189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206

	return 0;
}

int git_transaction_set_symbolic_target(git_transaction *tx, const char *refname, const char *target, const git_signature *sig, const char *msg)
{
	int error;
	transaction_node *node;

	assert(tx && refname && target);

	if ((error = find_locked(&node, tx, refname)) < 0)
		return error;

	if ((error = copy_common(node, tx, sig, msg)) < 0)
		return error;

	node->target.symbolic = git_pool_strdup(&tx->pool, target);
207
	GIT_ERROR_CHECK_ALLOC(node->target.symbolic);
208
	node->ref_type = GIT_REFERENCE_SYMBOLIC;
209 210 211 212 213 214 215 216 217 218 219 220 221

	return 0;
}

int git_transaction_remove(git_transaction *tx, const char *refname)
{
	int error;
	transaction_node *node;

	if ((error = find_locked(&node, tx, refname)) < 0)
		return error;

	node->remove = true;
222
	node->ref_type = GIT_REFERENCE_DIRECT; /* the id will be ignored */
223 224 225 226 227 228 229 230 231 232 233

	return 0;
}

static int dup_reflog(git_reflog **out, const git_reflog *in, git_pool *pool)
{
	git_reflog *reflog;
	git_reflog_entry *entries;
	size_t len, i;

	reflog = git_pool_mallocz(pool, sizeof(git_reflog));
234
	GIT_ERROR_CHECK_ALLOC(reflog);
235 236

	reflog->ref_name = git_pool_strdup(pool, in->ref_name);
237
	GIT_ERROR_CHECK_ALLOC(reflog->ref_name);
238 239 240 241

	len = in->entries.length;
	reflog->entries.length = len;
	reflog->entries.contents = git_pool_mallocz(pool, len * sizeof(void *));
242
	GIT_ERROR_CHECK_ALLOC(reflog->entries.contents);
243 244

	entries = git_pool_mallocz(pool, len * sizeof(git_reflog_entry));
245
	GIT_ERROR_CHECK_ALLOC(entries);
246 247 248 249 250 251 252 253 254 255 256 257 258

	for (i = 0; i < len; i++) {
		const git_reflog_entry *src;
		git_reflog_entry *tgt;

		tgt = &entries[i];
		reflog->entries.contents[i] = tgt;

		src = git_vector_get(&in->entries, i);
		git_oid_cpy(&tgt->oid_old, &src->oid_old);
		git_oid_cpy(&tgt->oid_cur, &src->oid_cur);

		tgt->msg = git_pool_strdup(pool, src->msg);
259
		GIT_ERROR_CHECK_ALLOC(tgt->msg);
260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290

		if (git_signature__pdup(&tgt->committer, src->committer, pool) < 0)
			return -1;
	}


	*out = reflog;
	return 0;
}

int git_transaction_set_reflog(git_transaction *tx, const char *refname, const git_reflog *reflog)
{
	int error;
	transaction_node *node;

	assert(tx && refname && reflog);

	if ((error = find_locked(&node, tx, refname)) < 0)
		return error;

	if ((error = dup_reflog(&node->reflog, reflog, &tx->pool)) < 0)
		return error;

	return 0;
}

static int update_target(git_refdb *db, transaction_node *node)
{
	git_reference *ref;
	int error, update_reflog;

291
	if (node->ref_type == GIT_REFERENCE_DIRECT) {
292
		ref = git_reference__alloc(node->name, &node->target.id, NULL);
293
	} else if (node->ref_type == GIT_REFERENCE_SYMBOLIC) {
294 295
		ref = git_reference__alloc_symbolic(node->name, node->target.symbolic);
	} else {
296
		abort();
297 298
	}

299
	GIT_ERROR_CHECK_ALLOC(ref);
300 301 302 303
	update_reflog = node->reflog == NULL;

	if (node->remove) {
		error =  git_refdb_unlock(db, node->payload, 2, false, ref, NULL, NULL);
304
	} else if (node->ref_type == GIT_REFERENCE_DIRECT) {
305
		error = git_refdb_unlock(db, node->payload, true, update_reflog, ref, node->sig, node->message);
306
	} else if (node->ref_type == GIT_REFERENCE_SYMBOLIC) {
307 308
		error = git_refdb_unlock(db, node->payload, true, update_reflog, ref, node->sig, node->message);
	} else {
309
		abort();
310 311 312 313 314 315 316 317 318 319 320
	}

	git_reference_free(ref);
	node->committed = true;

	return error;
}

int git_transaction_commit(git_transaction *tx)
{
	transaction_node *node;
321
	int error = 0;
322 323 324

	assert(tx);

325 326 327 328 329 330 331
	if (tx->type == TRANSACTION_CONFIG) {
		error = git_config_unlock(tx->cfg, true);
		tx->cfg = NULL;

		return error;
	}

332
	git_strmap_foreach_value(tx->locks, node, {
333 334 335 336 337
		if (node->reflog) {
			if ((error = tx->db->backend->reflog_write(tx->db->backend, node->reflog)) < 0)
				return error;
		}

338 339 340 341 342 343 344
		if (node->ref_type == GIT_REFERENCE_INVALID) {
			/* ref was locked but not modified */
			if ((error = git_refdb_unlock(tx->db, node->payload, false, false, NULL, NULL, NULL)) < 0) {
				return error;
			}
			node->committed = true;
		} else {
345 346 347
			if ((error = update_target(tx->db, node)) < 0)
				return error;
		}
348
	});
349 350 351 352 353 354 355 356 357 358 359

	return 0;
}

void git_transaction_free(git_transaction *tx)
{
	transaction_node *node;
	git_pool pool;

	assert(tx);

360 361 362 363 364 365 366 367 368 369
	if (tx->type == TRANSACTION_CONFIG) {
		if (tx->cfg) {
			git_config_unlock(tx->cfg, false);
			git_config_free(tx->cfg);
		}

		git__free(tx);
		return;
	}

370
	/* start by unlocking the ones we've left hanging, if any */
371
	git_strmap_foreach_value(tx->locks, node, {
372 373 374 375
		if (node->committed)
			continue;

		git_refdb_unlock(tx->db, node->payload, false, false, NULL, NULL, NULL);
376
	});
377 378 379 380 381 382 383 384

	git_refdb_free(tx->db);
	git_strmap_free(tx->locks);

	/* tx is inside the pool, so we need to extract the data */
	memcpy(&pool, &tx->pool, sizeof(git_pool));
	git_pool_clear(&pool);
}