refdb_fs.c 54.6 KB
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/*
 * 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.
 */

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#include "refdb_fs.h"

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#include "refs.h"
#include "hash.h"
#include "repository.h"
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#include "futils.h"
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#include "filebuf.h"
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#include "pack.h"
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#include "parse.h"
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#include "reflog.h"
#include "refdb.h"
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#include "iterator.h"
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#include "sortedcache.h"
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#include "signature.h"
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#include "wildmatch.h"
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#include <git2/tag.h>
#include <git2/object.h>
#include <git2/refdb.h>
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#include <git2/branch.h>
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#include <git2/sys/refdb_backend.h>
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#include <git2/sys/refs.h>
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#include <git2/sys/reflog.h>
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#define DEFAULT_NESTING_LEVEL	5
#define MAX_NESTING_LEVEL		10

enum {
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	PACKREF_HAS_PEEL = 1,
	PACKREF_WAS_LOOSE = 2,
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	PACKREF_CANNOT_PEEL = 4,
	PACKREF_SHADOWED = 8,
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};

enum {
	PEELING_NONE = 0,
	PEELING_STANDARD,
	PEELING_FULL
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};

struct packref {
	git_oid oid;
	git_oid peel;
	char flags;
	char name[GIT_FLEX_ARRAY];
};

typedef struct refdb_fs_backend {
	git_refdb_backend parent;

	git_repository *repo;
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	/* path to git directory */
	char *gitpath;
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	/* path to common objects' directory */
	char *commonpath;
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	git_sortedcache *refcache;
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	int peeling_mode;
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	git_iterator_flag_t iterator_flags;
	uint32_t direach_flags;
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	int fsync;
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} refdb_fs_backend;

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static int refdb_reflog_fs__delete(git_refdb_backend *_backend, const char *name);

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static int packref_cmp(const void *a_, const void *b_)
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{
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	const struct packref *a = a_, *b = b_;
	return strcmp(a->name, b->name);
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}

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static int packed_reload(refdb_fs_backend *backend)
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{
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	int error;
	git_buf packedrefs = GIT_BUF_INIT;
	char *scan, *eof, *eol;
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	if (!backend->gitpath)
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		return 0;

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	error = git_sortedcache_lockandload(backend->refcache, &packedrefs);
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	/*
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	 * If we can't find the packed-refs, clear table and return.
	 * Any other error just gets passed through.
	 * If no error, and file wasn't changed, just return.
	 * Anything else means we need to refresh the packed refs.
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	 */
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	if (error <= 0) {
		if (error == GIT_ENOTFOUND) {
			git_sortedcache_clear(backend->refcache, true);
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			git_error_clear();
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			error = 0;
		}
		return error;
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	}

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	/* At this point, refresh the packed refs from the loaded buffer. */
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	git_sortedcache_clear(backend->refcache, false);
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	scan = (char *)packedrefs.ptr;
	eof  = scan + packedrefs.size;
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	backend->peeling_mode = PEELING_NONE;

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	if (*scan == '#') {
nulltoken committed
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		static const char *traits_header = "# pack-refs with: ";
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		if (git__prefixcmp(scan, traits_header) == 0) {
			scan += strlen(traits_header);
			eol = strchr(scan, '\n');
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			if (!eol)
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				goto parse_failed;
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			*eol = '\0';
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			if (strstr(scan, " fully-peeled ") != NULL) {
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				backend->peeling_mode = PEELING_FULL;
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			} else if (strstr(scan, " peeled ") != NULL) {
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				backend->peeling_mode = PEELING_STANDARD;
			}

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			scan = eol + 1;
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		}
	}

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	while (scan < eof && *scan == '#') {
		if (!(eol = strchr(scan, '\n')))
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			goto parse_failed;
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		scan = eol + 1;
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	}

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	while (scan < eof) {
		struct packref *ref;
		git_oid oid;

		/* parse "<OID> <refname>\n" */
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		if (git_oid_fromstr(&oid, scan) < 0)
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			goto parse_failed;
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		scan += GIT_OID_HEXSZ;
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		if (*scan++ != ' ')
			goto parse_failed;
		if (!(eol = strchr(scan, '\n')))
			goto parse_failed;
		*eol = '\0';
		if (eol[-1] == '\r')
			eol[-1] = '\0';
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		if (git_sortedcache_upsert((void **)&ref, backend->refcache, scan) < 0)
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			goto parse_failed;
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		scan = eol + 1;

		git_oid_cpy(&ref->oid, &oid);

		/* look for optional "^<OID>\n" */

		if (*scan == '^') {
			if (git_oid_fromstr(&oid, scan + 1) < 0)
				goto parse_failed;
			scan += GIT_OID_HEXSZ + 1;

			if (scan < eof) {
				if (!(eol = strchr(scan, '\n')))
					goto parse_failed;
				scan = eol + 1;
			}

			git_oid_cpy(&ref->peel, &oid);
			ref->flags |= PACKREF_HAS_PEEL;
		}
		else if (backend->peeling_mode == PEELING_FULL ||
				(backend->peeling_mode == PEELING_STANDARD &&
				 git__prefixcmp(ref->name, GIT_REFS_TAGS_DIR) == 0))
			ref->flags |= PACKREF_CANNOT_PEEL;
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	}

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	git_sortedcache_wunlock(backend->refcache);
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	git_buf_dispose(&packedrefs);
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	return 0;

parse_failed:
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	git_error_set(GIT_ERROR_REFERENCE, "corrupted packed references file");
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	git_sortedcache_clear(backend->refcache, false);
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	git_sortedcache_wunlock(backend->refcache);
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	git_buf_dispose(&packedrefs);
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	return -1;
}

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static int loose_parse_oid(
	git_oid *oid, const char *filename, git_buf *file_content)
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{
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	const char *str = git_buf_cstr(file_content);
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	if (git_buf_len(file_content) < GIT_OID_HEXSZ)
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		goto corrupted;

	/* we need to get 40 OID characters from the file */
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	if (git_oid_fromstr(oid, str) < 0)
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		goto corrupted;

	/* If the file is longer than 40 chars, the 41st must be a space */
	str += GIT_OID_HEXSZ;
	if (*str == '\0' || git__isspace(*str))
		return 0;

corrupted:
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	git_error_set(GIT_ERROR_REFERENCE, "corrupted loose reference file: %s", filename);
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	return -1;
}

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static int loose_readbuffer(git_buf *buf, const char *base, const char *path)
{
	int error;

	/* build full path to file */
	if ((error = git_buf_joinpath(buf, base, path)) < 0 ||
		(error = git_futils_readbuffer(buf, buf->ptr)) < 0)
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		git_buf_dispose(buf);
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	return error;
}

static int loose_lookup_to_packfile(refdb_fs_backend *backend, const char *name)
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{
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	int error = 0;
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	git_buf ref_file = GIT_BUF_INIT;
	struct packref *ref = NULL;
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	git_oid oid;
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	/* if we fail to load the loose reference, assume someone changed
	 * the filesystem under us and skip it...
	 */
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	if (loose_readbuffer(&ref_file, backend->gitpath, name) < 0) {
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		git_error_clear();
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		goto done;
	}
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	/* skip symbolic refs */
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	if (!git__prefixcmp(git_buf_cstr(&ref_file), GIT_SYMREF))
		goto done;
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	/* parse OID from file */
	if ((error = loose_parse_oid(&oid, name, &ref_file)) < 0)
		goto done;
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	git_sortedcache_wlock(backend->refcache);
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	if (!(error = git_sortedcache_upsert(
			(void **)&ref, backend->refcache, name))) {
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		git_oid_cpy(&ref->oid, &oid);
		ref->flags = PACKREF_WAS_LOOSE;
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	}

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	git_sortedcache_wunlock(backend->refcache);
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done:
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	git_buf_dispose(&ref_file);
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	return error;
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}

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static int _dirent_loose_load(void *payload, git_buf *full_path)
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{
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	refdb_fs_backend *backend = payload;
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	const char *file_path;

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	if (git__suffixcmp(full_path->ptr, ".lock") == 0)
		return 0;

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	if (git_path_isdir(full_path->ptr)) {
		int error = git_path_direach(
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			full_path, backend->direach_flags, _dirent_loose_load, backend);
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		/* Race with the filesystem, ignore it */
		if (error == GIT_ENOTFOUND) {
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			git_error_clear();
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			return 0;
		}

		return error;
	}
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	file_path = full_path->ptr + strlen(backend->gitpath);
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	return loose_lookup_to_packfile(backend, file_path);
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}

/*
 * Load all the loose references from the repository
 * into the in-memory Packfile, and build a vector with
 * all the references so it can be written back to
 * disk.
 */
static int packed_loadloose(refdb_fs_backend *backend)
{
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	int error;
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	git_buf refs_path = GIT_BUF_INIT;

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	if (git_buf_joinpath(&refs_path, backend->gitpath, GIT_REFS_DIR) < 0)
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		return -1;

	/*
	 * Load all the loose files from disk into the Packfile table.
	 * This will overwrite any old packed entries with their
	 * updated loose versions
	 */
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	error = git_path_direach(
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		&refs_path, backend->direach_flags, _dirent_loose_load, backend);
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	git_buf_dispose(&refs_path);
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	return error;
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}

static int refdb_fs_backend__exists(
	int *exists,
	git_refdb_backend *_backend,
	const char *ref_name)
{
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	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
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	git_buf ref_path = GIT_BUF_INIT;
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	int error;
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	assert(backend);
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	*exists = 0;

	if ((error = git_buf_joinpath(&ref_path, backend->gitpath, ref_name)) < 0)
		goto out;

	if (git_path_isfile(ref_path.ptr)) {
		*exists = 1;
		goto out;
	}
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	if ((error = packed_reload(backend)) < 0)
		goto out;
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	if (git_sortedcache_lookup(backend->refcache, ref_name) != NULL) {
		*exists = 1;
		goto out;
	}

out:
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	git_buf_dispose(&ref_path);
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	return error;
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}

static const char *loose_parse_symbolic(git_buf *file_content)
{
	const unsigned int header_len = (unsigned int)strlen(GIT_SYMREF);
	const char *refname_start;

	refname_start = (const char *)file_content->ptr;

	if (git_buf_len(file_content) < header_len + 1) {
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		git_error_set(GIT_ERROR_REFERENCE, "corrupted loose reference file");
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		return NULL;
	}

	/*
	 * Assume we have already checked for the header
	 * before calling this function
	 */
	refname_start += header_len;

	return refname_start;
}

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/*
 * Returns whether a reference is stored per worktree or not.
 * Per-worktree references are:
 *
 * - all pseudorefs, e.g. HEAD and MERGE_HEAD
 * - all references stored inside of "refs/bisect/"
 */
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static bool is_per_worktree_ref(const char *ref_name)
{
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	return git__prefixcmp(ref_name, "refs/") != 0 ||
	    git__prefixcmp(ref_name, "refs/bisect/") == 0;
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}

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static int loose_lookup(
	git_reference **out,
	refdb_fs_backend *backend,
	const char *ref_name)
{
	git_buf ref_file = GIT_BUF_INIT;
	int error = 0;
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	const char *ref_dir;
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	if (out)
		*out = NULL;

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	if (is_per_worktree_ref(ref_name))
		ref_dir = backend->gitpath;
	else
		ref_dir = backend->commonpath;

	if ((error = loose_readbuffer(&ref_file, ref_dir, ref_name)) < 0)
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		/* cannot read loose ref file - gah */;
	else if (git__prefixcmp(git_buf_cstr(&ref_file), GIT_SYMREF) == 0) {
		const char *target;
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		git_buf_rtrim(&ref_file);

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		if (!(target = loose_parse_symbolic(&ref_file)))
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			error = -1;
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		else if (out != NULL)
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			*out = git_reference__alloc_symbolic(ref_name, target);
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	} else {
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		git_oid oid;
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		if (!(error = loose_parse_oid(&oid, ref_name, &ref_file)) &&
			out != NULL)
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			*out = git_reference__alloc(ref_name, &oid, NULL);
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	}

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	git_buf_dispose(&ref_file);
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	return error;
}

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static int ref_error_notfound(const char *name)
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{
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	git_error_set(GIT_ERROR_REFERENCE, "reference '%s' not found", name);
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	return GIT_ENOTFOUND;
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}

static int packed_lookup(
	git_reference **out,
	refdb_fs_backend *backend,
	const char *ref_name)
{
	int error = 0;
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	struct packref *entry;
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	if ((error = packed_reload(backend)) < 0)
		return error;
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	if (git_sortedcache_rlock(backend->refcache) < 0)
		return -1;
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	entry = git_sortedcache_lookup(backend->refcache, ref_name);
	if (!entry) {
		error = ref_error_notfound(ref_name);
	} else {
		*out = git_reference__alloc(ref_name, &entry->oid, &entry->peel);
		if (!*out)
			error = -1;
	}

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	git_sortedcache_runlock(backend->refcache);

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	return error;
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}

static int refdb_fs_backend__lookup(
	git_reference **out,
	git_refdb_backend *_backend,
	const char *ref_name)
{
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	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
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	int error;
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	assert(backend);
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	if (!(error = loose_lookup(out, backend, ref_name)))
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		return 0;

	/* only try to lookup this reference on the packfile if it
	 * wasn't found on the loose refs; not if there was a critical error */
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	if (error == GIT_ENOTFOUND) {
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		git_error_clear();
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		error = packed_lookup(out, backend, ref_name);
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	}

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	return error;
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}

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typedef struct {
	git_reference_iterator parent;
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	char *glob;
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	git_pool pool;
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	git_vector loose;
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	git_sortedcache *cache;
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	size_t loose_pos;
	size_t packed_pos;
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} refdb_fs_iter;

static void refdb_fs_backend__iterator_free(git_reference_iterator *_iter)
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{
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	refdb_fs_iter *iter = GIT_CONTAINER_OF(_iter, refdb_fs_iter, parent);
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	git_vector_free(&iter->loose);
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	git_pool_clear(&iter->pool);
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	git_sortedcache_free(iter->cache);
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	git__free(iter);
}
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static int iter_load_loose_paths(refdb_fs_backend *backend, refdb_fs_iter *iter)
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{
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	int error = 0;
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	git_buf path = GIT_BUF_INIT;
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	git_iterator *fsit = NULL;
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	git_iterator_options fsit_opts = GIT_ITERATOR_OPTIONS_INIT;
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	const git_index_entry *entry = NULL;
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	const char *ref_prefix = GIT_REFS_DIR;
	size_t ref_prefix_len = strlen(ref_prefix);
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	if (!backend->commonpath) /* do nothing if no commonpath for loose refs */
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		return 0;

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	fsit_opts.flags = backend->iterator_flags;

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	if (iter->glob) {
		const char *last_sep = NULL;
		const char *pos;
		for (pos = iter->glob; *pos; ++pos) {
			switch (*pos) {
			case '?':
			case '*':
			case '[':
			case '\\':
				break;
			case '/':
				last_sep = pos;
				/* FALLTHROUGH */
			default:
				continue;
			}
			break;
		}
		if (last_sep) {
			ref_prefix = iter->glob;
			ref_prefix_len = (last_sep - ref_prefix) + 1;
		}
	}

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	if ((error = git_buf_printf(&path, "%s/", backend->commonpath)) < 0 ||
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		(error = git_buf_put(&path, ref_prefix, ref_prefix_len)) < 0) {
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		git_buf_dispose(&path);
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		return error;
	}
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	if ((error = git_iterator_for_filesystem(&fsit, path.ptr, &fsit_opts)) < 0) {
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		git_buf_dispose(&path);
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		return (iter->glob && error == GIT_ENOTFOUND)? 0 : error;
	}

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	error = git_buf_sets(&path, ref_prefix);
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	while (!error && !git_iterator_advance(&entry, fsit)) {
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		const char *ref_name;
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		char *ref_dup;
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		git_buf_truncate(&path, ref_prefix_len);
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		git_buf_puts(&path, entry->path);
		ref_name = git_buf_cstr(&path);
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		if (git__suffixcmp(ref_name, ".lock") == 0 ||
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			(iter->glob && wildmatch(iter->glob, ref_name, 0) != 0))
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			continue;
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		ref_dup = git_pool_strdup(&iter->pool, ref_name);
		if (!ref_dup)
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			error = -1;
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		else
			error = git_vector_insert(&iter->loose, ref_dup);
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	}
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	git_iterator_free(fsit);
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	git_buf_dispose(&path);
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	return error;
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}

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static int refdb_fs_backend__iterator_next(
	git_reference **out, git_reference_iterator *_iter)
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{
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	int error = GIT_ITEROVER;
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	refdb_fs_iter *iter = GIT_CONTAINER_OF(_iter, refdb_fs_iter, parent);
	refdb_fs_backend *backend = GIT_CONTAINER_OF(iter->parent.db->backend, refdb_fs_backend, parent);
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	struct packref *ref;
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	while (iter->loose_pos < iter->loose.length) {
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		const char *path = git_vector_get(&iter->loose, iter->loose_pos++);
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		if (loose_lookup(out, backend, path) == 0) {
			ref = git_sortedcache_lookup(iter->cache, path);
			if (ref)
				ref->flags |= PACKREF_SHADOWED;

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			return 0;
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		}
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		git_error_clear();
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	}
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	error = GIT_ITEROVER;
	while (iter->packed_pos < git_sortedcache_entrycount(iter->cache)) {
		ref = git_sortedcache_entry(iter->cache, iter->packed_pos++);
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		if (!ref) /* stop now if another thread deleted refs and we past end */
			break;
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		if (ref->flags & PACKREF_SHADOWED)
			continue;
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		if (iter->glob && wildmatch(iter->glob, ref->name, 0) != 0)
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			continue;
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		*out = git_reference__alloc(ref->name, &ref->oid, &ref->peel);
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		error = (*out != NULL) ? 0 : -1;
		break;
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	}

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	return error;
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}

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static int refdb_fs_backend__iterator_next_name(
	const char **out, git_reference_iterator *_iter)
{
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	int error = GIT_ITEROVER;
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	refdb_fs_iter *iter = GIT_CONTAINER_OF(_iter, refdb_fs_iter, parent);
	refdb_fs_backend *backend = GIT_CONTAINER_OF(iter->parent.db->backend, refdb_fs_backend, parent);
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	struct packref *ref;
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	while (iter->loose_pos < iter->loose.length) {
		const char *path = git_vector_get(&iter->loose, iter->loose_pos++);
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		struct packref *ref;
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		if (loose_lookup(NULL, backend, path) == 0) {
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			ref = git_sortedcache_lookup(iter->cache, path);
			if (ref)
				ref->flags |= PACKREF_SHADOWED;

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			*out = path;
			return 0;
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		}

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		git_error_clear();
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	}

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	error = GIT_ITEROVER;
	while (iter->packed_pos < git_sortedcache_entrycount(iter->cache)) {
		ref = git_sortedcache_entry(iter->cache, iter->packed_pos++);
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		if (!ref) /* stop now if another thread deleted refs and we past end */
			break;
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		if (ref->flags & PACKREF_SHADOWED)
			continue;
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		if (iter->glob && wildmatch(iter->glob, ref->name, 0) != 0)
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			continue;

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		*out = ref->name;
		error = 0;
		break;
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	}

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	return error;
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}

static int refdb_fs_backend__iterator(
	git_reference_iterator **out, git_refdb_backend *_backend, const char *glob)
{
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	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
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	refdb_fs_iter *iter = NULL;
	int error;
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	assert(backend);
684 685

	iter = git__calloc(1, sizeof(refdb_fs_iter));
686
	GIT_ERROR_CHECK_ALLOC(iter);
687

688 689
	git_pool_init(&iter->pool, 1);

690 691
	if ((error = git_vector_init(&iter->loose, 8, NULL)) < 0)
		goto out;
692 693

	if (glob != NULL &&
694 695 696 697 698
	    (iter->glob = git_pool_strdup(&iter->pool, glob)) == NULL) {
		error = GIT_ERROR_NOMEMORY;
		goto out;
	}

699
	if ((error = iter_load_loose_paths(backend, iter)) < 0)
700 701
		goto out;

702
	if ((error = packed_reload(backend)) < 0)
703
		goto out;
704 705 706

	if ((error = git_sortedcache_copy(&iter->cache, backend->refcache, 1, NULL, NULL)) < 0)
		goto out;
707 708 709 710 711 712

	iter->parent.next = refdb_fs_backend__iterator_next;
	iter->parent.next_name = refdb_fs_backend__iterator_next_name;
	iter->parent.free = refdb_fs_backend__iterator_free;

	*out = (git_reference_iterator *)iter;
713 714 715 716
out:
	if (error)
		refdb_fs_backend__iterator_free((git_reference_iterator *)iter);
	return error;
717 718
}

Vicent Marti committed
719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736 737 738 739 740 741
static bool ref_is_available(
	const char *old_ref, const char *new_ref, const char *this_ref)
{
	if (old_ref == NULL || strcmp(old_ref, this_ref)) {
		size_t reflen = strlen(this_ref);
		size_t newlen = strlen(new_ref);
		size_t cmplen = reflen < newlen ? reflen : newlen;
		const char *lead = reflen < newlen ? new_ref : this_ref;

		if (!strncmp(new_ref, this_ref, cmplen) && lead[cmplen] == '/') {
			return false;
		}
	}

	return true;
}

static int reference_path_available(
	refdb_fs_backend *backend,
	const char *new_ref,
	const char* old_ref,
	int force)
{
742
	size_t i;
743
	int error;
Vicent Marti committed
744

745 746
	if ((error = packed_reload(backend)) < 0)
		return error;
Vicent Marti committed
747 748 749 750

	if (!force) {
		int exists;

751 752 753 754
		if ((error = refdb_fs_backend__exists(
			&exists, (git_refdb_backend *)backend, new_ref)) < 0) {
			return error;
		}
Vicent Marti committed
755 756

		if (exists) {
757
			git_error_set(GIT_ERROR_REFERENCE,
758
				"failed to write reference '%s': a reference with "
759
				"that name already exists.", new_ref);
Vicent Marti committed
760 761 762 763
			return GIT_EEXISTS;
		}
	}

764
	git_sortedcache_rlock(backend->refcache);
765 766

	for (i = 0; i < git_sortedcache_entrycount(backend->refcache); ++i) {
767
		struct packref *ref = git_sortedcache_entry(backend->refcache, i);
768

769 770
		if (ref && !ref_is_available(old_ref, new_ref, ref->name)) {
			git_sortedcache_runlock(backend->refcache);
771
			git_error_set(GIT_ERROR_REFERENCE,
772
				"path to reference '%s' collides with existing one", new_ref);
Vicent Marti committed
773 774
			return -1;
		}
775
	}
776

777
	git_sortedcache_runlock(backend->refcache);
Vicent Marti committed
778 779
	return 0;
}
780

781
static int loose_lock(git_filebuf *file, refdb_fs_backend *backend, const char *name)
782
{
783
	int error, filebuf_flags;
784
	git_buf ref_path = GIT_BUF_INIT;
785
	const char *basedir;
786

787
	assert(file && backend && name);
788

789
	if (!git_path_isvalid(backend->repo, name, 0, GIT_PATH_REJECT_FILESYSTEM_DEFAULTS)) {
790
		git_error_set(GIT_ERROR_INVALID, "invalid reference name '%s'", name);
791 792 793
		return GIT_EINVALIDSPEC;
	}

794 795 796 797 798
	if (is_per_worktree_ref(name))
		basedir = backend->gitpath;
	else
		basedir = backend->commonpath;

799 800 801
	/* Remove a possibly existing empty directory hierarchy
	 * which name would collide with the reference name
	 */
802
	if ((error = git_futils_rmdir_r(name, basedir, GIT_RMDIR_SKIP_NONEMPTY)) < 0)
803
		return error;
804

805
	if (git_buf_joinpath(&ref_path, basedir, name) < 0)
806 807
		return -1;

808
	filebuf_flags = GIT_FILEBUF_CREATE_LEADING_DIRS;
809
	if (backend->fsync)
810 811 812
		filebuf_flags |= GIT_FILEBUF_FSYNC;

	error = git_filebuf_open(file, ref_path.ptr, filebuf_flags, GIT_REFS_FILE_MODE);
813

814
	if (error == GIT_EDIRECTORY)
815
		git_error_set(GIT_ERROR_REFERENCE, "cannot lock ref '%s', there are refs beneath that folder", name);
816

817
	git_buf_dispose(&ref_path);
818
	return error;
819
}
820

821 822
static int loose_commit(git_filebuf *file, const git_reference *ref)
{
823 824
	assert(file && ref);

825
	if (ref->type == GIT_REFERENCE_DIRECT) {
826
		char oid[GIT_OID_HEXSZ + 1];
827
		git_oid_nfmt(oid, sizeof(oid), &ref->target.oid);
828

829
		git_filebuf_printf(file, "%s\n", oid);
830
	} else if (ref->type == GIT_REFERENCE_SYMBOLIC) {
831
		git_filebuf_printf(file, GIT_SYMREF "%s\n", ref->target.symbolic);
832 833 834 835
	} else {
		assert(0); /* don't let this happen */
	}

836
	return git_filebuf_commit(file);
837 838
}

839 840 841 842
static int refdb_fs_backend__lock(void **out, git_refdb_backend *_backend, const char *refname)
{
	int error;
	git_filebuf *lock;
843
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
844 845

	lock = git__calloc(1, sizeof(git_filebuf));
846
	GIT_ERROR_CHECK_ALLOC(lock);
847 848 849 850 851 852 853 854 855 856 857 858 859 860 861 862

	if ((error = loose_lock(lock, backend, refname)) < 0) {
		git__free(lock);
		return error;
	}

	*out = lock;
	return 0;
}

static int refdb_fs_backend__write_tail(
	git_refdb_backend *_backend,
	const git_reference *ref,
	git_filebuf *file,
	int update_reflog,
	const git_oid *old_id,
863 864 865
	const char *old_target,
	const git_signature *who,
	const char *message);
866 867 868 869 870

static int refdb_fs_backend__delete_tail(
	git_refdb_backend *_backend,
	git_filebuf *file,
	const char *ref_name,
871 872
	const git_oid *old_id,
	const char *old_target);
873 874 875 876 877 878 879 880 881 882

static int refdb_fs_backend__unlock(git_refdb_backend *backend, void *payload, int success, int update_reflog,
				    const git_reference *ref, const git_signature *sig, const char *message)
{
	git_filebuf *lock = (git_filebuf *) payload;
	int error = 0;

	if (success == 2)
		error = refdb_fs_backend__delete_tail(backend, lock, ref->name, NULL, NULL);
	else if (success)
883
		error = refdb_fs_backend__write_tail(backend, ref, lock, update_reflog, NULL, NULL, sig, message);
884 885 886 887 888 889 890
	else
		git_filebuf_cleanup(lock);

	git__free(lock);
	return error;
}

891 892 893 894 895 896 897 898 899 900 901 902
/*
 * Find out what object this reference resolves to.
 *
 * For references that point to a 'big' tag (e.g. an
 * actual tag object on the repository), we need to
 * cache on the packfile the OID of the object to
 * which that 'big tag' is pointing to.
 */
static int packed_find_peel(refdb_fs_backend *backend, struct packref *ref)
{
	git_object *object;

903
	if (ref->flags & PACKREF_HAS_PEEL || ref->flags & PACKREF_CANNOT_PEEL)
904 905 906 907 908
		return 0;

	/*
	 * Find the tagged object in the repository
	 */
909
	if (git_object_lookup(&object, backend->repo, &ref->oid, GIT_OBJECT_ANY) < 0)
910 911 912 913 914 915 916
		return -1;

	/*
	 * If the tagged object is a Tag object, we need to resolve it;
	 * if the ref is actually a 'weak' ref, we don't need to resolve
	 * anything.
	 */
917
	if (git_object_type(object) == GIT_OBJECT_TAG) {
918 919 920 921 922 923
		git_tag *tag = (git_tag *)object;

		/*
		 * Find the object pointed at by this tag
		 */
		git_oid_cpy(&ref->peel, git_tag_target_id(tag));
924
		ref->flags |= PACKREF_HAS_PEEL;
925 926 927 928 929 930 931 932 933 934 935 936 937 938 939 940 941 942

		/*
		 * The reference has now cached the resolved OID, and is
		 * marked at such. When written to the packfile, it'll be
		 * accompanied by this resolved oid
		 */
	}

	git_object_free(object);
	return 0;
}

/*
 * Write a single reference into a packfile
 */
static int packed_write_ref(struct packref *ref, git_filebuf *file)
{
	char oid[GIT_OID_HEXSZ + 1];
943
	git_oid_nfmt(oid, sizeof(oid), &ref->oid);
944 945 946 947 948 949 950 951 952 953 954

	/*
	 * For references that peel to an object in the repo, we must
	 * write the resulting peel on a separate line, e.g.
	 *
	 *	6fa8a902cc1d18527e1355773c86721945475d37 refs/tags/libgit2-0.4
	 *	^2ec0cb7959b0bf965d54f95453f5b4b34e8d3100
	 *
	 * This obviously only applies to tags.
	 * The required peels have already been loaded into `ref->peel_target`.
	 */
955
	if (ref->flags & PACKREF_HAS_PEEL) {
956
		char peel[GIT_OID_HEXSZ + 1];
957
		git_oid_nfmt(peel, sizeof(peel), &ref->peel);
958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979

		if (git_filebuf_printf(file, "%s %s\n^%s\n", oid, ref->name, peel) < 0)
			return -1;
	} else {
		if (git_filebuf_printf(file, "%s %s\n", oid, ref->name) < 0)
			return -1;
	}

	return 0;
}

/*
 * Remove all loose references
 *
 * Once we have successfully written a packfile,
 * all the loose references that were packed must be
 * removed from disk.
 *
 * This is a dangerous method; make sure the packfile
 * is well-written, because we are destructing references
 * here otherwise.
 */
980
static int packed_remove_loose(refdb_fs_backend *backend)
981
{
982
	size_t i;
983
	git_filebuf lock = GIT_FILEBUF_INIT;
984
	git_buf ref_content = GIT_BUF_INIT;
985
	int error = 0;
986

987 988 989 990
	/* backend->refcache is already locked when this is called */

	for (i = 0; i < git_sortedcache_entrycount(backend->refcache); ++i) {
		struct packref *ref = git_sortedcache_entry(backend->refcache, i);
991
		git_oid current_id;
992

993
		if (!ref || !(ref->flags & PACKREF_WAS_LOOSE))
994 995
			continue;

996 997
		git_filebuf_cleanup(&lock);

998 999 1000
		/* We need to stop anybody from updating the ref while we try to do a safe delete */
		error = loose_lock(&lock, backend, ref->name);
		/* If someone else is updating it, let them do it */
1001
		if (error == GIT_EEXISTS || error == GIT_ENOTFOUND)
1002 1003 1004
			continue;

		if (error < 0) {
1005
			git_buf_dispose(&ref_content);
1006
			git_error_set(GIT_ERROR_REFERENCE, "failed to lock loose reference '%s'", ref->name);
1007
			return error;
1008 1009 1010 1011
		}

		error = git_futils_readbuffer(&ref_content, lock.path_original);
		/* Someone else beat us to cleaning up the ref, let's simply continue */
1012
		if (error == GIT_ENOTFOUND)
1013 1014 1015
			continue;

		/* This became a symref between us packing and trying to delete it, so ignore it */
1016
		if (!git__prefixcmp(ref_content.ptr, GIT_SYMREF))
1017 1018
			continue;

1019 1020
		/* Figure out the current id; if we find a bad ref file, skip it so we can do the rest */
		if (loose_parse_oid(&current_id, lock.path_original, &ref_content) < 0)
1021
			continue;
1022

1023
		/* If the ref moved since we packed it, we must not delete it */
1024
		if (!git_oid_equal(&current_id, &ref->oid))
1025 1026
			continue;

1027 1028 1029
		/*
		 * if we fail to remove a single file, this is *not* good,
		 * but we should keep going and remove as many as possible.
1030 1031
		 * If we fail to remove, the ref is still in the old state, so
		 * we haven't lost information.
1032
		 */
1033
		p_unlink(lock.path_original);
1034 1035
	}

1036
	git_buf_dispose(&ref_content);
1037
	git_filebuf_cleanup(&lock);
1038
	return 0;
1039 1040 1041 1042 1043 1044 1045
}

/*
 * Write all the contents in the in-memory packfile to disk.
 */
static int packed_write(refdb_fs_backend *backend)
{
1046
	git_sortedcache *refcache = backend->refcache;
1047
	git_filebuf pack_file = GIT_FILEBUF_INIT;
1048
	int error, open_flags = 0;
1049
	size_t i;
1050

1051
	/* lock the cache to updates while we do this */
1052 1053
	if ((error = git_sortedcache_wlock(refcache)) < 0)
		return error;
1054

1055
	if (backend->fsync)
1056 1057
		open_flags = GIT_FILEBUF_FSYNC;

1058
	/* Open the file! */
1059
	if ((error = git_filebuf_open(&pack_file, git_sortedcache_path(refcache), open_flags, GIT_PACKEDREFS_FILE_MODE)) < 0)
1060
		goto fail;
1061 1062 1063 1064

	/* Packfiles have a header... apparently
	 * This is in fact not required, but we might as well print it
	 * just for kicks */
1065
	if ((error = git_filebuf_printf(&pack_file, "%s\n", GIT_PACKEDREFS_HEADER)) < 0)
1066
		goto fail;
1067

1068 1069
	for (i = 0; i < git_sortedcache_entrycount(refcache); ++i) {
		struct packref *ref = git_sortedcache_entry(refcache, i);
1070
		assert(ref);
1071

1072
		if ((error = packed_find_peel(backend, ref)) < 0)
1073
			goto fail;
1074

1075
		if ((error = packed_write_ref(ref, &pack_file)) < 0)
1076
			goto fail;
1077 1078 1079 1080
	}

	/* if we've written all the references properly, we can commit
	 * the packfile to make the changes effective */
1081
	if ((error = git_filebuf_commit(&pack_file)) < 0)
1082
		goto fail;
1083 1084 1085

	/* when and only when the packfile has been properly written,
	 * we can go ahead and remove the loose refs */
1086
	if ((error = packed_remove_loose(backend)) < 0)
1087
		goto fail;
1088

1089 1090
	git_sortedcache_updated(refcache);
	git_sortedcache_wunlock(refcache);
1091 1092 1093 1094

	/* we're good now */
	return 0;

1095
fail:
1096
	git_filebuf_cleanup(&pack_file);
1097
	git_sortedcache_wunlock(refcache);
1098

1099
	return error;
1100 1101
}

1102 1103 1104
static int packed_delete(refdb_fs_backend *backend, const char *ref_name)
{
	size_t pack_pos;
1105
	int error, found = 0;
1106 1107 1108 1109 1110 1111 1112

	if ((error = packed_reload(backend)) < 0)
		goto cleanup;

	if ((error = git_sortedcache_wlock(backend->refcache)) < 0)
		goto cleanup;

1113 1114 1115
	/* If a packed reference exists, remove it from the packfile and repack if necessary */
	error = git_sortedcache_lookup_index(&pack_pos, backend->refcache, ref_name);
	if (error == 0) {
1116
		error = git_sortedcache_remove(backend->refcache, pack_pos);
1117 1118 1119 1120
		found = 1;
	}
	if (error == GIT_ENOTFOUND)
		error = 0;
1121 1122 1123

	git_sortedcache_wunlock(backend->refcache);

1124 1125
	if (found)
		error = packed_write(backend);
1126 1127 1128 1129 1130

cleanup:
	return error;
}

1131
static int reflog_append(refdb_fs_backend *backend, const git_reference *ref, const git_oid *old, const git_oid *new, const git_signature *author, const char *message);
1132 1133
static int has_reflog(git_repository *repo, const char *name);

1134
static int should_write_reflog(int *write, git_repository *repo, const char *name)
1135
{
1136
	int error, logall;
1137

1138
	error = git_repository__configmap_lookup(&logall, repo, GIT_CONFIGMAP_LOGALLREFUPDATES);
1139
	if (error < 0)
1140 1141
		return error;

1142 1143 1144
	/* Defaults to the opposite of the repo being bare */
	if (logall == GIT_LOGALLREFUPDATES_UNSET)
		logall = !git_repository_is_bare(repo);
1145

1146 1147 1148
	*write = 0;
	switch (logall) {
	case GIT_LOGALLREFUPDATES_FALSE:
1149
		*write = 0;
1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163
		break;

	case GIT_LOGALLREFUPDATES_TRUE:
		/* Only write if it already has a log,
		 * or if it's under heads/, remotes/ or notes/
		 */
		*write = has_reflog(repo, name) ||
			!git__prefixcmp(name, GIT_REFS_HEADS_DIR) ||
			!git__strcmp(name, GIT_HEAD_FILE) ||
			!git__prefixcmp(name, GIT_REFS_REMOTES_DIR) ||
			!git__prefixcmp(name, GIT_REFS_NOTES_DIR);
		break;

	case GIT_LOGALLREFUPDATES_ALWAYS:
1164
		*write = 1;
1165
		break;
1166
	}
1167 1168 1169

	return 0;
}
1170

1171
static int cmp_old_ref(int *cmp, git_refdb_backend *backend, const char *name,
1172 1173 1174 1175 1176 1177
	const git_oid *old_id, const char *old_target)
{
	int error = 0;
	git_reference *old_ref = NULL;

	*cmp = 0;
1178 1179 1180 1181 1182 1183 1184 1185
	/* It "matches" if there is no old value to compare against */
	if (!old_id && !old_target)
		return 0;

	if ((error = refdb_fs_backend__lookup(&old_ref, backend, name)) < 0)
		goto out;

	/* If the types don't match, there's no way the values do */
1186
	if (old_id && old_ref->type != GIT_REFERENCE_DIRECT) {
1187 1188 1189
		*cmp = -1;
		goto out;
	}
1190
	if (old_target && old_ref->type != GIT_REFERENCE_SYMBOLIC) {
1191 1192
		*cmp = 1;
		goto out;
1193 1194
	}

1195
	if (old_id && old_ref->type == GIT_REFERENCE_DIRECT)
1196 1197
		*cmp = git_oid_cmp(old_id, &old_ref->target.oid);

1198
	if (old_target && old_ref->type == GIT_REFERENCE_SYMBOLIC)
1199 1200 1201 1202 1203 1204 1205 1206
		*cmp = git__strcmp(old_target, old_ref->target.symbolic);

out:
	git_reference_free(old_ref);

	return error;
}

1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 1220 1221 1222 1223
/*
 * The git.git comment regarding this, for your viewing pleasure:
 *
 * Special hack: If a branch is updated directly and HEAD
 * points to it (may happen on the remote side of a push
 * for example) then logically the HEAD reflog should be
 * updated too.
 * A generic solution implies reverse symref information,
 * but finding all symrefs pointing to the given branch
 * would be rather costly for this rare event (the direct
 * update of a branch) to be worth it.  So let's cheat and
 * check with HEAD only which should cover 99% of all usage
 * scenarios (even 100% of the default ones).
 */
static int maybe_append_head(refdb_fs_backend *backend, const git_reference *ref, const git_signature *who, const char *message)
{
	int error;
1224
	git_oid old_id;
1225 1226 1227
	git_reference *tmp = NULL, *head = NULL, *peeled = NULL;
	const char *name;

1228
	if (ref->type == GIT_REFERENCE_SYMBOLIC)
1229
		return 0;
1230

1231
	/* if we can't resolve, we use {0}*40 as old id */
1232 1233
	if (git_reference_name_to_id(&old_id, backend->repo, ref->name) < 0)
		memset(&old_id, 0, sizeof(old_id));
1234

1235
	if ((error = git_reference_lookup(&head, backend->repo, GIT_HEAD_FILE)) < 0)
1236 1237
		return error;

1238
	if (git_reference_type(head) == GIT_REFERENCE_DIRECT)
1239 1240
		goto cleanup;

1241 1242 1243 1244
	if ((error = git_reference_lookup(&tmp, backend->repo, GIT_HEAD_FILE)) < 0)
		goto cleanup;

	/* Go down the symref chain until we find the branch */
1245
	while (git_reference_type(tmp) == GIT_REFERENCE_SYMBOLIC) {
1246 1247 1248 1249 1250 1251 1252 1253 1254 1255 1256 1257 1258 1259 1260 1261 1262 1263
		error = git_reference_lookup(&peeled, backend->repo, git_reference_symbolic_target(tmp));
		if (error < 0)
			break;

		git_reference_free(tmp);
		tmp = peeled;
	}

	if (error == GIT_ENOTFOUND) {
		error = 0;
		name = git_reference_symbolic_target(tmp);
	} else if (error < 0) {
		goto cleanup;
	} else {
		name = git_reference_name(tmp);
	}

	if (strcmp(name, ref->name))
1264 1265
		goto cleanup;

1266 1267
	error = reflog_append(backend, head, &old_id, git_reference_target(ref), who, message);

1268
cleanup:
1269
	git_reference_free(tmp);
1270 1271 1272 1273
	git_reference_free(head);
	return error;
}

1274 1275
static int refdb_fs_backend__write(
	git_refdb_backend *_backend,
Vicent Marti committed
1276
	const git_reference *ref,
1277
	int force,
1278
	const git_signature *who,
1279
	const char *message,
1280 1281
	const git_oid *old_id,
	const char *old_target)
1282
{
1283
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1284
	git_filebuf file = GIT_FILEBUF_INIT;
1285
	int error = 0;
1286

1287
	assert(backend);
1288

1289
	if ((error = reference_path_available(backend, ref->name, NULL, force)) < 0)
Vicent Marti committed
1290 1291
		return error;

1292
	/* We need to perform the reflog append and old value check under the ref's lock */
1293
	if ((error = loose_lock(&file, backend, ref->name)) < 0)
1294 1295
		return error;

1296
	return refdb_fs_backend__write_tail(_backend, ref, &file, true, old_id, old_target, who, message);
1297 1298 1299 1300 1301 1302 1303 1304
}

static int refdb_fs_backend__write_tail(
	git_refdb_backend *_backend,
	const git_reference *ref,
	git_filebuf *file,
	int update_reflog,
	const git_oid *old_id,
1305 1306 1307
	const char *old_target,
	const git_signature *who,
	const char *message)
1308
{
1309
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1310 1311 1312 1313
	int error = 0, cmp = 0, should_write;
	const char *new_target = NULL;
	const git_oid *new_id = NULL;

1314
	if ((error = cmp_old_ref(&cmp, _backend, ref->name, old_id, old_target)) < 0)
1315
		goto on_error;
1316 1317

	if (cmp) {
1318
		git_error_set(GIT_ERROR_REFERENCE, "old reference value does not match");
1319 1320
		error = GIT_EMODIFIED;
		goto on_error;
1321 1322
	}

1323
	if (ref->type == GIT_REFERENCE_SYMBOLIC)
1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337
		new_target = ref->target.symbolic;
	else
		new_id = &ref->target.oid;

	error = cmp_old_ref(&cmp, _backend, ref->name, new_id, new_target);
	if (error < 0 && error != GIT_ENOTFOUND)
		goto on_error;

	/* Don't update if we have the same value */
	if (!error && !cmp) {
		error = 0;
		goto on_error; /* not really error */
	}

1338 1339
	if (update_reflog) {
		if ((error = should_write_reflog(&should_write, backend->repo, ref->name)) < 0)
1340
			goto on_error;
1341 1342 1343 1344 1345 1346 1347

		if (should_write) {
			if ((error = reflog_append(backend, ref, NULL, NULL, who, message)) < 0)
				goto on_error;
			if ((error = maybe_append_head(backend, ref, who, message)) < 0)
				goto on_error;
		}
1348 1349
	}

1350
	return loose_commit(file, ref);
1351 1352

on_error:
1353
        git_filebuf_cleanup(file);
1354
        return error;
1355 1356
}

1357
static void refdb_fs_backend__prune_refs(
1358 1359
	refdb_fs_backend *backend,
	const char *ref_name,
1360
	const char *prefix)
1361 1362 1363 1364 1365 1366 1367 1368 1369 1370 1371 1372 1373 1374 1375 1376 1377
{
	git_buf relative_path = GIT_BUF_INIT;
	git_buf base_path = GIT_BUF_INIT;
	size_t commonlen;

	assert(backend && ref_name);

	if (git_buf_sets(&relative_path, ref_name) < 0)
		goto cleanup;

	git_path_squash_slashes(&relative_path);
	if ((commonlen = git_path_common_dirlen("refs/heads/", git_buf_cstr(&relative_path))) == strlen("refs/heads/") ||
		(commonlen = git_path_common_dirlen("refs/tags/", git_buf_cstr(&relative_path))) == strlen("refs/tags/") ||
		(commonlen = git_path_common_dirlen("refs/remotes/", git_buf_cstr(&relative_path))) == strlen("refs/remotes/")) {

		git_buf_truncate(&relative_path, commonlen);

1378 1379
		if (prefix) {
			if (git_buf_join3(&base_path, '/', backend->commonpath, prefix, git_buf_cstr(&relative_path)) < 0)
1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 1390 1391 1392 1393
				goto cleanup;
		} else {
			if (git_buf_joinpath(&base_path, backend->commonpath, git_buf_cstr(&relative_path)) < 0)
				goto cleanup;
		}

		git_futils_rmdir_r(ref_name + commonlen, git_buf_cstr(&base_path), GIT_RMDIR_EMPTY_PARENTS | GIT_RMDIR_SKIP_ROOT);
	}

cleanup:
	git_buf_dispose(&relative_path);
	git_buf_dispose(&base_path);
}

1394 1395
static int refdb_fs_backend__delete(
	git_refdb_backend *_backend,
1396 1397
	const char *ref_name,
	const git_oid *old_id, const char *old_target)
1398
{
1399
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1400
	git_filebuf file = GIT_FILEBUF_INIT;
1401
	int error = 0;
1402

1403
	assert(backend && ref_name);
1404

1405 1406 1407
	if ((error = loose_lock(&file, backend, ref_name)) < 0)
		return error;

1408 1409 1410 1411 1412
	if ((error = refdb_reflog_fs__delete(_backend, ref_name)) < 0) {
		git_filebuf_cleanup(&file);
		return error;
	}

1413 1414 1415
	return refdb_fs_backend__delete_tail(_backend, &file, ref_name, old_id, old_target);
}

1416 1417 1418 1419 1420 1421 1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432 1433 1434
static int loose_delete(refdb_fs_backend *backend, const char *ref_name)
{
	git_buf loose_path = GIT_BUF_INIT;
	int error = 0;

	if (git_buf_joinpath(&loose_path, backend->commonpath, ref_name) < 0)
		return -1;

	error = p_unlink(loose_path.ptr);
	if (error < 0 && errno == ENOENT)
		error = GIT_ENOTFOUND;
	else if (error != 0)
		error = -1;

	git_buf_dispose(&loose_path);

	return error;
}

1435 1436 1437 1438 1439 1440
static int refdb_fs_backend__delete_tail(
	git_refdb_backend *_backend,
	git_filebuf *file,
	const char *ref_name,
	const git_oid *old_id, const char *old_target)
{
1441
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1442
	int error = 0, cmp = 0;
1443
	bool packed_deleted = 0;
1444

1445 1446 1447 1448 1449
	error = cmp_old_ref(&cmp, _backend, ref_name, old_id, old_target);
	if (error < 0)
		goto cleanup;

	if (cmp) {
1450
		git_error_set(GIT_ERROR_REFERENCE, "old reference value does not match");
1451 1452 1453 1454
		error = GIT_EMODIFIED;
		goto cleanup;
	}

1455 1456 1457 1458 1459 1460 1461 1462 1463 1464 1465 1466 1467 1468 1469 1470 1471 1472
	/*
	 * To ensure that an external observer will see either the current ref value
	 * (because the loose ref still exists), or a missing ref (after the packed-file is
	 * unlocked, there will be nothing left), we must ensure things happen in the
	 * following order:
	 *
	 * - the packed-ref file is locked and loaded, as well as a loose one, if it exists
	 * - we optimistically delete a packed ref, keeping track of whether it existed
	 * - we delete the loose ref, note that we have its .lock
	 * - the loose ref is "unlocked", then the packed-ref file is rewritten and unlocked
	 * - we should prune the path components if a loose ref was deleted
	 *
	 * Note that, because our packed backend doesn't expose its filesystem lock,
	 * we might not be able to guarantee that this is what actually happens (ie.
	 * as our current code never write packed-refs.lock, nothing stops observers
	 * from grabbing a "stale" value from there).
	 */
	if ((error = packed_delete(backend, ref_name)) < 0 && error != GIT_ENOTFOUND)
1473
		goto cleanup;
1474

1475 1476
	if (error == 0)
		packed_deleted = 1;
1477

1478
	if ((error = loose_delete(backend, ref_name)) < 0 && error != GIT_ENOTFOUND)
1479
		goto cleanup;
Vicent Marti committed
1480

1481
	if (error == GIT_ENOTFOUND) {
1482
		error = packed_deleted ? 0 : ref_error_notfound(ref_name);
1483 1484 1485 1486
		goto cleanup;
	}

cleanup:
1487
	git_filebuf_cleanup(file);
1488
	if (error == 0)
1489
		refdb_fs_backend__prune_refs(backend, ref_name, "");
1490
	return error;
1491 1492
}

1493 1494
static int refdb_reflog_fs__rename(git_refdb_backend *_backend, const char *old_name, const char *new_name);

Vicent Marti committed
1495 1496 1497 1498 1499
static int refdb_fs_backend__rename(
	git_reference **out,
	git_refdb_backend *_backend,
	const char *old_name,
	const char *new_name,
1500
	int force,
1501
	const git_signature *who,
1502
	const char *message)
Vicent Marti committed
1503
{
1504
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
Vicent Marti committed
1505
	git_reference *old, *new;
1506
	git_filebuf file = GIT_FILEBUF_INIT;
Vicent Marti committed
1507 1508
	int error;

1509
	assert(backend);
Vicent Marti committed
1510

1511 1512 1513
	if ((error = reference_path_available(
			backend, new_name, old_name, force)) < 0 ||
		(error = refdb_fs_backend__lookup(&old, _backend, old_name)) < 0)
Vicent Marti committed
1514 1515
		return error;

1516
	if ((error = refdb_fs_backend__delete(_backend, old_name, NULL, NULL)) < 0) {
Vicent Marti committed
1517 1518 1519 1520
		git_reference_free(old);
		return error;
	}

1521 1522 1523 1524
	new = git_reference__set_name(old, new_name);
	if (!new) {
		git_reference_free(old);
		return -1;
Vicent Marti committed
1525 1526
	}

1527
	if ((error = loose_lock(&file, backend, new->name)) < 0) {
1528 1529 1530 1531 1532 1533 1534
		git_reference_free(new);
		return error;
	}

	/* Try to rename the refog; it's ok if the old doesn't exist */
	error = refdb_reflog_fs__rename(_backend, old_name, new_name);
	if (((error == 0) || (error == GIT_ENOTFOUND)) &&
1535
	    ((error = reflog_append(backend, new, git_reference_target(new), NULL, who, message)) < 0)) {
1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548
		git_reference_free(new);
		git_filebuf_cleanup(&file);
		return error;
	}

	if (error < 0) {
		git_reference_free(new);
		git_filebuf_cleanup(&file);
		return error;
	}


	if ((error = loose_commit(&file, new)) < 0 || out == NULL) {
Vicent Marti committed
1549
		git_reference_free(new);
1550
		return error;
Vicent Marti committed
1551 1552
	}

1553
	*out = new;
Vicent Marti committed
1554 1555 1556
	return 0;
}

1557 1558
static int refdb_fs_backend__compress(git_refdb_backend *_backend)
{
1559
	int error;
1560
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1561

1562
	assert(backend);
1563

1564 1565 1566 1567
	if ((error = packed_reload(backend)) < 0 || /* load the existing packfile */
	    (error = packed_loadloose(backend)) < 0 || /* add all the loose refs */
	    (error = packed_write(backend)) < 0) /* write back to disk */
		return error;
1568 1569 1570 1571 1572 1573

	return 0;
}

static void refdb_fs_backend__free(git_refdb_backend *_backend)
{
1574
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1575

1576
	assert(backend);
1577

1578
	git_sortedcache_free(backend->refcache);
1579
	git__free(backend->gitpath);
1580
	git__free(backend->commonpath);
1581 1582 1583
	git__free(backend);
}

1584
static char *setup_namespace(git_repository *repo, const char *in)
1585
{
1586 1587
	git_buf path = GIT_BUF_INIT;
	char *parts, *start, *end, *out = NULL;
1588

1589 1590
	if (!in)
		goto done;
1591

1592
	git_buf_puts(&path, in);
1593 1594

	/* if the repo is not namespaced, nothing else to do */
1595 1596 1597 1598
	if (repo->namespace == NULL) {
		out = git_buf_detach(&path);
		goto done;
	}
1599 1600 1601

	parts = end = git__strdup(repo->namespace);
	if (parts == NULL)
1602
		goto done;
1603

1604
	/*
1605 1606 1607 1608 1609
	 * From `man gitnamespaces`:
	 *  namespaces which include a / will expand to a hierarchy
	 *  of namespaces; for example, GIT_NAMESPACE=foo/bar will store
	 *  refs under refs/namespaces/foo/refs/namespaces/bar/
	 */
1610 1611
	while ((start = git__strsep(&end, "/")) != NULL)
		git_buf_printf(&path, "refs/namespaces/%s/", start);
1612

1613
	git_buf_printf(&path, "refs/namespaces/%s/refs", end);
Vicent Marti committed
1614
	git__free(parts);
1615 1616

	/* Make sure that the folder with the namespace exists */
1617 1618 1619
	if (git_futils_mkdir_relative(git_buf_cstr(&path), in, 0777,
			GIT_MKDIR_PATH, NULL) < 0)
		goto done;
1620

1621
	/* Return root of the namespaced gitpath, i.e. without the trailing '/refs' */
1622 1623 1624 1625
	git_buf_rtruncate_at_char(&path, '/');
	out = git_buf_detach(&path);

done:
1626
	git_buf_dispose(&path);
1627
	return out;
1628 1629
}

1630 1631 1632 1633 1634 1635 1636
static int reflog_alloc(git_reflog **reflog, const char *name)
{
	git_reflog *log;

	*reflog = NULL;

	log = git__calloc(1, sizeof(git_reflog));
1637
	GIT_ERROR_CHECK_ALLOC(log);
1638 1639

	log->ref_name = git__strdup(name);
1640
	GIT_ERROR_CHECK_ALLOC(log->ref_name);
1641 1642 1643 1644 1645 1646 1647 1648 1649 1650 1651 1652 1653 1654

	if (git_vector_init(&log->entries, 0, NULL) < 0) {
		git__free(log->ref_name);
		git__free(log);
		return -1;
	}

	*reflog = log;

	return 0;
}

static int reflog_parse(git_reflog *log, const char *buf, size_t buf_size)
{
1655
	git_parse_ctx parser = GIT_PARSE_CTX_INIT;
1656

1657 1658
	if ((git_parse_ctx_init(&parser, buf, buf_size)) < 0)
		return -1;
1659

1660
	for (; parser.remain_len; git_parse_advance_line(&parser)) {
1661
		git_reflog_entry *entry;
1662 1663
		const char *sig;
		char c;
1664

1665 1666 1667 1668
		entry = git__calloc(1, sizeof(*entry));
		GIT_ERROR_CHECK_ALLOC(entry);
		entry->committer = git__calloc(1, sizeof(*entry->committer));
		GIT_ERROR_CHECK_ALLOC(entry->committer);
1669

1670 1671 1672
		if (git_parse_advance_oid(&entry->oid_old, &parser) < 0 ||
		    git_parse_advance_expected(&parser, " ", 1) < 0 ||
		    git_parse_advance_oid(&entry->oid_cur, &parser) < 0)
1673
			goto next;
1674

1675 1676 1677
		sig = parser.line;
		while (git_parse_peek(&c, &parser, 0) == 0 && c != '\t' && c != '\n')
			git_parse_advance_chars(&parser, 1);
1678

1679
		if (git_signature__parse(entry->committer, &sig, parser.line, NULL, 0) < 0)
1680
			goto next;
1681

1682 1683 1684
		if (c == '\t') {
			size_t len;
			git_parse_advance_chars(&parser, 1);
1685

1686 1687 1688
			len = parser.line_len;
			if (parser.line[len - 1] == '\n')
				len--;
1689

1690
			entry->msg = git__strndup(parser.line, len);
1691
			GIT_ERROR_CHECK_ALLOC(entry->msg);
1692
		}
1693

1694 1695 1696 1697
		if ((git_vector_insert(&log->entries, entry)) < 0) {
			git_reflog_entry__free(entry);
			return -1;
		}
1698

1699
		continue;
1700

1701 1702 1703
next:
		git_reflog_entry__free(entry);
	}
1704

1705
	return 0;
1706 1707 1708 1709 1710 1711 1712 1713 1714 1715
}

static int create_new_reflog_file(const char *filepath)
{
	int fd, error;

	if ((error = git_futils_mkpath2file(filepath, GIT_REFLOG_DIR_MODE)) < 0)
		return error;

	if ((fd = p_open(filepath,
1716
			O_WRONLY | O_CREAT,
1717 1718 1719 1720 1721 1722 1723 1724
			GIT_REFLOG_FILE_MODE)) < 0)
		return -1;

	return p_close(fd);
}

GIT_INLINE(int) retrieve_reflog_path(git_buf *path, git_repository *repo, const char *name)
{
1725 1726
	if (strcmp(name, GIT_HEAD_FILE) == 0)
		return git_buf_join3(path, '/', repo->gitdir, GIT_REFLOG_DIR, name);
1727
	return git_buf_join3(path, '/', repo->commondir, GIT_REFLOG_DIR, name);
1728 1729
}

1730 1731 1732 1733 1734 1735 1736 1737 1738
static int refdb_reflog_fs__ensure_log(git_refdb_backend *_backend, const char *name)
{
	refdb_fs_backend *backend;
	git_repository *repo;
	git_buf path = GIT_BUF_INIT;
	int error;

	assert(_backend && name);

1739
	backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1740 1741 1742 1743 1744
	repo = backend->repo;

	if ((error = retrieve_reflog_path(&path, repo, name)) < 0)
		return error;

1745
	error = create_new_reflog_file(git_buf_cstr(&path));
1746
	git_buf_dispose(&path);
1747 1748

	return error;
1749 1750
}

1751 1752 1753 1754 1755 1756 1757 1758 1759 1760 1761
static int has_reflog(git_repository *repo, const char *name)
{
	int ret = 0;
	git_buf path = GIT_BUF_INIT;

	if (retrieve_reflog_path(&path, repo, name) < 0)
		goto cleanup;

	ret = git_path_isfile(git_buf_cstr(&path));

cleanup:
1762
	git_buf_dispose(&path);
1763 1764 1765
	return ret;
}

1766 1767 1768 1769 1770 1771
static int refdb_reflog_fs__has_log(git_refdb_backend *_backend, const char *name)
{
	refdb_fs_backend *backend;

	assert(_backend && name);

1772
	backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1773 1774 1775 1776

	return has_reflog(backend->repo, name);
}

1777 1778 1779 1780 1781 1782 1783 1784 1785 1786 1787
static int refdb_reflog_fs__read(git_reflog **out, git_refdb_backend *_backend, const char *name)
{
	int error = -1;
	git_buf log_path = GIT_BUF_INIT;
	git_buf log_file = GIT_BUF_INIT;
	git_reflog *log = NULL;
	git_repository *repo;
	refdb_fs_backend *backend;

	assert(out && _backend && name);

1788
	backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1789 1790 1791 1792 1793 1794 1795 1796 1797 1798 1799 1800 1801 1802 1803
	repo = backend->repo;

	if (reflog_alloc(&log, name) < 0)
		return -1;

	if (retrieve_reflog_path(&log_path, repo, name) < 0)
		goto cleanup;

	error = git_futils_readbuffer(&log_file, git_buf_cstr(&log_path));
	if (error < 0 && error != GIT_ENOTFOUND)
		goto cleanup;

	if ((error == GIT_ENOTFOUND) &&
		((error = create_new_reflog_file(git_buf_cstr(&log_path))) < 0))
		goto cleanup;
1804

1805 1806 1807 1808 1809 1810 1811 1812 1813 1814 1815
	if ((error = reflog_parse(log,
		git_buf_cstr(&log_file), git_buf_len(&log_file))) < 0)
		goto cleanup;

	*out = log;
	goto success;

cleanup:
	git_reflog_free(log);

success:
1816 1817
	git_buf_dispose(&log_file);
	git_buf_dispose(&log_path);
1818 1819 1820 1821 1822 1823 1824 1825 1826 1827 1828 1829 1830 1831 1832 1833 1834 1835 1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846

	return error;
}

static int serialize_reflog_entry(
	git_buf *buf,
	const git_oid *oid_old,
	const git_oid *oid_new,
	const git_signature *committer,
	const char *msg)
{
	char raw_old[GIT_OID_HEXSZ+1];
	char raw_new[GIT_OID_HEXSZ+1];

	git_oid_tostr(raw_old, GIT_OID_HEXSZ+1, oid_old);
	git_oid_tostr(raw_new, GIT_OID_HEXSZ+1, oid_new);

	git_buf_clear(buf);

	git_buf_puts(buf, raw_old);
	git_buf_putc(buf, ' ');
	git_buf_puts(buf, raw_new);

	git_signature__writebuf(buf, " ", committer);

	/* drop trailing LF */
	git_buf_rtrim(buf);

	if (msg) {
1847 1848
		size_t i;

1849 1850
		git_buf_putc(buf, '\t');
		git_buf_puts(buf, msg);
1851 1852 1853 1854 1855

		for (i = 0; i < buf->size - 2; i++)
			if (buf->ptr[i] == '\n')
				buf->ptr[i] = ' ';
		git_buf_rtrim(buf);
1856 1857 1858 1859 1860 1861 1862
	}

	git_buf_putc(buf, '\n');

	return git_buf_oom(buf);
}

1863 1864 1865 1866 1867 1868 1869 1870
static int lock_reflog(git_filebuf *file, refdb_fs_backend *backend, const char *refname)
{
	git_repository *repo;
	git_buf log_path = GIT_BUF_INIT;
	int error;

	repo = backend->repo;

1871
	if (!git_path_isvalid(backend->repo, refname, 0, GIT_PATH_REJECT_FILESYSTEM_DEFAULTS)) {
1872
		git_error_set(GIT_ERROR_INVALID, "invalid reference name '%s'", refname);
1873 1874 1875
		return GIT_EINVALIDSPEC;
	}

1876 1877 1878 1879
	if (retrieve_reflog_path(&log_path, repo, refname) < 0)
		return -1;

	if (!git_path_isfile(git_buf_cstr(&log_path))) {
1880
		git_error_set(GIT_ERROR_INVALID,
1881
			"log file for reference '%s' doesn't exist", refname);
1882 1883 1884 1885 1886 1887 1888
		error = -1;
		goto cleanup;
	}

	error = git_filebuf_open(file, git_buf_cstr(&log_path), 0, GIT_REFLOG_FILE_MODE);

cleanup:
1889
	git_buf_dispose(&log_path);
1890 1891 1892 1893

	return error;
}

1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904
static int refdb_reflog_fs__write(git_refdb_backend *_backend, git_reflog *reflog)
{
	int error = -1;
	unsigned int i;
	git_reflog_entry *entry;
	refdb_fs_backend *backend;
	git_buf log = GIT_BUF_INIT;
	git_filebuf fbuf = GIT_FILEBUF_INIT;

	assert(_backend && reflog);

1905
	backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
1906

1907
	if ((error = lock_reflog(&fbuf, backend, reflog->ref_name)) < 0)
1908 1909 1910 1911 1912 1913 1914 1915 1916 1917
		return -1;

	git_vector_foreach(&reflog->entries, i, entry) {
		if (serialize_reflog_entry(&log, &(entry->oid_old), &(entry->oid_cur), entry->committer, entry->msg) < 0)
			goto cleanup;

		if ((error = git_filebuf_write(&fbuf, log.ptr, log.size)) < 0)
			goto cleanup;
	}

1918
	error = git_filebuf_commit(&fbuf);
1919 1920 1921 1922 1923 1924
	goto success;

cleanup:
	git_filebuf_cleanup(&fbuf);

success:
1925
	git_buf_dispose(&log);
1926

1927 1928 1929
	return error;
}

1930
/* Append to the reflog, must be called under reference lock */
1931
static int reflog_append(refdb_fs_backend *backend, const git_reference *ref, const git_oid *old, const git_oid *new, const git_signature *who, const char *message)
1932
{
1933
	int error, is_symbolic, open_flags;
1934
	git_oid old_id = {{0}}, new_id = {{0}};
1935 1936 1937
	git_buf buf = GIT_BUF_INIT, path = GIT_BUF_INIT;
	git_repository *repo = backend->repo;

1938
	is_symbolic = ref->type == GIT_REFERENCE_SYMBOLIC;
1939 1940 1941 1942 1943

	/* "normal" symbolic updates do not write */
	if (is_symbolic &&
	    strcmp(ref->name, GIT_HEAD_FILE) &&
	    !(old && new))
1944 1945
		return 0;

Etienne Samson committed
1946
	/* From here on is_symbolic also means that it's HEAD */
1947 1948 1949

	if (old) {
		git_oid_cpy(&old_id, old);
1950
	} else {
1951
		error = git_reference_name_to_id(&old_id, repo, ref->name);
1952
		if (error < 0 && error != GIT_ENOTFOUND)
1953 1954 1955
			return error;
	}

1956 1957 1958 1959 1960 1961 1962 1963 1964 1965 1966 1967
	if (new) {
		git_oid_cpy(&new_id, new);
	} else {
		if (!is_symbolic) {
			git_oid_cpy(&new_id, git_reference_target(ref));
		} else {
			error = git_reference_name_to_id(&new_id, repo, git_reference_symbolic_target(ref));
			if (error < 0 && error != GIT_ENOTFOUND)
				return error;
			/* detaching HEAD does not create an entry */
			if (error == GIT_ENOTFOUND)
				return 0;
1968

1969
			git_error_clear();
1970
		}
1971
	}
1972

1973 1974 1975 1976 1977 1978 1979 1980 1981 1982 1983
	if ((error = serialize_reflog_entry(&buf, &old_id, &new_id, who, message)) < 0)
		goto cleanup;

	if ((error = retrieve_reflog_path(&path, repo, ref->name)) < 0)
		goto cleanup;

	if (((error = git_futils_mkpath2file(git_buf_cstr(&path), 0777)) < 0) &&
	    (error != GIT_EEXISTS)) {
		goto cleanup;
	}

1984 1985 1986
	/* If the new branch matches part of the namespace of a previously deleted branch,
	 * there maybe an obsolete/unused directory (or directory hierarchy) in the way.
	 */
1987
	if (git_path_isdir(git_buf_cstr(&path))) {
1988 1989 1990 1991
		if ((error = git_futils_rmdir_r(git_buf_cstr(&path), NULL, GIT_RMDIR_SKIP_NONEMPTY)) < 0) {
			if (error == GIT_ENOTFOUND)
				error = 0;
		} else if (git_path_isdir(git_buf_cstr(&path))) {
1992
			git_error_set(GIT_ERROR_REFERENCE, "cannot create reflog at '%s', there are reflogs beneath that folder",
1993 1994 1995 1996 1997 1998
				ref->name);
			error = GIT_EDIRECTORY;
		}

		if (error != 0)
			goto cleanup;
1999 2000
	}

2001 2002
	open_flags = O_WRONLY | O_CREAT | O_APPEND;

2003
	if (backend->fsync)
2004 2005 2006
		open_flags |= O_FSYNC;

	error = git_futils_writebuffer(&buf, git_buf_cstr(&path), open_flags, GIT_REFLOG_FILE_MODE);
2007 2008

cleanup:
2009 2010
	git_buf_dispose(&buf);
	git_buf_dispose(&path);
2011

2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026
	return error;
}

static int refdb_reflog_fs__rename(git_refdb_backend *_backend, const char *old_name, const char *new_name)
{
	int error = 0, fd;
	git_buf old_path = GIT_BUF_INIT;
	git_buf new_path = GIT_BUF_INIT;
	git_buf temp_path = GIT_BUF_INIT;
	git_buf normalized = GIT_BUF_INIT;
	git_repository *repo;
	refdb_fs_backend *backend;

	assert(_backend && old_name && new_name);

2027
	backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
2028 2029 2030
	repo = backend->repo;

	if ((error = git_reference__normalize_name(
2031
		&normalized, new_name, GIT_REFERENCE_FORMAT_ALLOW_ONELEVEL)) < 0)
2032 2033
			return error;

2034
	if (git_buf_joinpath(&temp_path, repo->gitdir, GIT_REFLOG_DIR) < 0)
2035 2036 2037 2038 2039 2040 2041 2042
		return -1;

	if (git_buf_joinpath(&old_path, git_buf_cstr(&temp_path), old_name) < 0)
		return -1;

	if (git_buf_joinpath(&new_path, git_buf_cstr(&temp_path), git_buf_cstr(&normalized)) < 0)
		return -1;

2043 2044 2045 2046 2047
	if (!git_path_exists(git_buf_cstr(&old_path))) {
		error = GIT_ENOTFOUND;
		goto cleanup;
	}

2048 2049 2050 2051 2052 2053 2054 2055 2056 2057
	/*
	 * Move the reflog to a temporary place. This two-phase renaming is required
	 * in order to cope with funny renaming use cases when one tries to move a reference
	 * to a partially colliding namespace:
	 *  - a/b -> a/b/c
	 *  - a/b/c/d -> a/b/c
	 */
	if (git_buf_joinpath(&temp_path, git_buf_cstr(&temp_path), "temp_reflog") < 0)
		return -1;

2058
	if ((fd = git_futils_mktmp(&temp_path, git_buf_cstr(&temp_path), GIT_REFLOG_FILE_MODE)) < 0) {
2059 2060 2061 2062 2063 2064 2065
		error = -1;
		goto cleanup;
	}

	p_close(fd);

	if (p_rename(git_buf_cstr(&old_path), git_buf_cstr(&temp_path)) < 0) {
2066
		git_error_set(GIT_ERROR_OS, "failed to rename reflog for %s", new_name);
2067 2068 2069 2070
		error = -1;
		goto cleanup;
	}

2071
	if (git_path_isdir(git_buf_cstr(&new_path)) &&
2072 2073 2074 2075 2076 2077 2078 2079 2080 2081 2082
		(git_futils_rmdir_r(git_buf_cstr(&new_path), NULL, GIT_RMDIR_SKIP_NONEMPTY) < 0)) {
		error = -1;
		goto cleanup;
	}

	if (git_futils_mkpath2file(git_buf_cstr(&new_path), GIT_REFLOG_DIR_MODE) < 0) {
		error = -1;
		goto cleanup;
	}

	if (p_rename(git_buf_cstr(&temp_path), git_buf_cstr(&new_path)) < 0) {
2083
		git_error_set(GIT_ERROR_OS, "failed to rename reflog for %s", new_name);
2084 2085 2086 2087
		error = -1;
	}

cleanup:
2088 2089 2090 2091
	git_buf_dispose(&temp_path);
	git_buf_dispose(&old_path);
	git_buf_dispose(&new_path);
	git_buf_dispose(&normalized);
2092 2093 2094 2095 2096 2097

	return error;
}

static int refdb_reflog_fs__delete(git_refdb_backend *_backend, const char *name)
{
2098
	refdb_fs_backend *backend = GIT_CONTAINER_OF(_backend, refdb_fs_backend, parent);
2099
	git_buf path = GIT_BUF_INIT;
2100
	int error;
2101 2102 2103

	assert(_backend && name);

2104 2105
	if ((error = retrieve_reflog_path(&path, backend->repo, name)) < 0)
		goto out;
2106

2107 2108
	if (!git_path_exists(path.ptr))
		goto out;
2109

2110 2111
	if ((error = p_unlink(path.ptr)) < 0)
		goto out;
2112

2113
	refdb_fs_backend__prune_refs(backend, name, GIT_REFLOG_DIR);
2114 2115

out:
2116
	git_buf_dispose(&path);
2117 2118 2119 2120

	return error;
}

2121 2122
int git_refdb_backend_fs(
	git_refdb_backend **backend_out,
2123
	git_repository *repository)
2124
{
2125
	int t = 0;
2126
	git_buf gitpath = GIT_BUF_INIT;
2127 2128 2129
	refdb_fs_backend *backend;

	backend = git__calloc(1, sizeof(refdb_fs_backend));
2130
	GIT_ERROR_CHECK_ALLOC(backend);
2131 2132

	backend->repo = repository;
Vicent Marti committed
2133

2134 2135
	if (repository->gitdir) {
		backend->gitpath = setup_namespace(repository, repository->gitdir);
Vicent Marti committed
2136

2137 2138 2139 2140 2141 2142 2143 2144 2145 2146
		if (backend->gitpath == NULL)
			goto fail;
	}

	if (repository->commondir) {
		backend->commonpath = setup_namespace(repository, repository->commondir);

		if (backend->commonpath == NULL)
			goto fail;
	}
2147

2148
	if (git_buf_joinpath(&gitpath, backend->commonpath, GIT_PACKEDREFS_FILE) < 0 ||
2149 2150
		git_sortedcache_new(
			&backend->refcache, offsetof(struct packref, name),
2151
			NULL, NULL, packref_cmp, git_buf_cstr(&gitpath)) < 0)
2152 2153
		goto fail;

2154
	git_buf_dispose(&gitpath);
2155

2156
	if (!git_repository__configmap_lookup(&t, backend->repo, GIT_CONFIGMAP_IGNORECASE) && t) {
2157 2158 2159
		backend->iterator_flags |= GIT_ITERATOR_IGNORE_CASE;
		backend->direach_flags  |= GIT_PATH_DIR_IGNORE_CASE;
	}
2160
	if (!git_repository__configmap_lookup(&t, backend->repo, GIT_CONFIGMAP_PRECOMPOSE) && t) {
2161 2162 2163
		backend->iterator_flags |= GIT_ITERATOR_PRECOMPOSE_UNICODE;
		backend->direach_flags  |= GIT_PATH_DIR_PRECOMPOSE_UNICODE;
	}
2164
	if ((!git_repository__configmap_lookup(&t, backend->repo, GIT_CONFIGMAP_FSYNCOBJECTFILES) && t) ||
2165
		git_repository__fsync_gitdir)
2166
		backend->fsync = 1;
2167
	backend->iterator_flags |= GIT_ITERATOR_DESCEND_SYMLINKS;
2168

2169 2170
	backend->parent.exists = &refdb_fs_backend__exists;
	backend->parent.lookup = &refdb_fs_backend__lookup;
2171
	backend->parent.iterator = &refdb_fs_backend__iterator;
2172
	backend->parent.write = &refdb_fs_backend__write;
2173
	backend->parent.del = &refdb_fs_backend__delete;
Vicent Marti committed
2174
	backend->parent.rename = &refdb_fs_backend__rename;
2175
	backend->parent.compress = &refdb_fs_backend__compress;
2176 2177
	backend->parent.lock = &refdb_fs_backend__lock;
	backend->parent.unlock = &refdb_fs_backend__unlock;
2178
	backend->parent.has_log = &refdb_reflog_fs__has_log;
2179
	backend->parent.ensure_log = &refdb_reflog_fs__ensure_log;
2180
	backend->parent.free = &refdb_fs_backend__free;
2181 2182 2183 2184
	backend->parent.reflog_read = &refdb_reflog_fs__read;
	backend->parent.reflog_write = &refdb_reflog_fs__write;
	backend->parent.reflog_rename = &refdb_reflog_fs__rename;
	backend->parent.reflog_delete = &refdb_reflog_fs__delete;
2185 2186 2187

	*backend_out = (git_refdb_backend *)backend;
	return 0;
2188 2189

fail:
2190
	git_buf_dispose(&gitpath);
2191
	git__free(backend->gitpath);
2192
	git__free(backend->commonpath);
2193 2194
	git__free(backend);
	return -1;
2195
}