int transport_fetch_refs(struct transport *transport, struct ref *refs)
{
	int rc;
	int nr_heads = 0, nr_alloc = 0, nr_refs = 0;
	struct ref **heads = NULL;
	struct ref *rm;

	for (rm = refs; rm; rm = rm->next) {
		nr_refs++;
		if (rm->peer_ref &&
		    !is_null_sha1(rm->old_sha1) &&
		    !hashcmp(rm->peer_ref->old_sha1, rm->old_sha1))
			continue;
		ALLOC_GROW(heads, nr_heads + 1, nr_alloc);
		heads[nr_heads++] = rm;
	}

	if (!nr_heads) {
		/*
		 * When deepening of a shallow repository is requested,
		 * then local and remote refs are likely to still be equal.
		 * Just feed them all to the fetch method in that case.
		 * This condition shouldn't be met in a non-deepening fetch
		 * (see builtin-fetch.c:quickfetch()).
		 */
		heads = xmalloc(nr_refs * sizeof(*heads));
		for (rm = refs; rm; rm = rm->next)
			heads[nr_heads++] = rm;
	}

	rc = transport->fetch(transport, nr_heads, heads);

	free(heads);
	return rc;
}

void add_exclude(const char *string, const char *base,
		 int baselen, struct exclude_list *el, int srcpos)
{
	struct exclude *x;
	int patternlen;
	int flags;
	int nowildcardlen;

	parse_exclude_pattern(&string, &patternlen, &flags, &nowildcardlen);
	if (flags & EXC_FLAG_MUSTBEDIR) {
		char *s;
		x = xmalloc(sizeof(*x) + patternlen + 1);
		s = (char *)(x+1);
		memcpy(s, string, patternlen);
		s[patternlen] = '\0';
		x->pattern = s;
	} else {
		x = xmalloc(sizeof(*x));
		x->pattern = string;
	}
	x->patternlen = patternlen;
	x->nowildcardlen = nowildcardlen;
	x->base = base;
	x->baselen = baselen;
	x->flags = flags;
	x->srcpos = srcpos;
	ALLOC_GROW(el->excludes, el->nr + 1, el->alloc);
	el->excludes[el->nr++] = x;
	x->el = el;
}

static int read_loose_refs(struct strbuf *path, int name_offset,
		struct ref **tail)
{
	DIR *dir = opendir(path->buf);
	struct dirent *de;
	struct {
		char **entries;
		int nr, alloc;
	} list;
	int i, pathlen;

	if (!dir)
		return -1;

	memset (&list, 0, sizeof(list));

	while ((de = readdir(dir))) {
		if (is_dot_or_dotdot(de->d_name))
			continue;
		ALLOC_GROW(list.entries, list.nr + 1, list.alloc);
		list.entries[list.nr++] = xstrdup(de->d_name);
	}
	closedir(dir);

	/* sort the list */

	qsort(list.entries, list.nr, sizeof(char *), str_cmp);

	pathlen = path->len;
	strbuf_addch(path, '/');

	for (i = 0; i < list.nr; i++, strbuf_setlen(path, pathlen + 1)) {
		strbuf_addstr(path, list.entries[i]);
		if (read_loose_refs(path, name_offset, tail)) {
			int fd = open(path->buf, O_RDONLY);
			char buffer[40];
			struct ref *next;

			if (fd < 0)
				continue;
			next = alloc_ref(path->buf + name_offset);
			if (read_in_full(fd, buffer, 40) != 40 ||
					get_oid_hex(buffer, &next->old_oid)) {
				close(fd);
				free(next);
				continue;
			}
			close(fd);
			(*tail)->next = next;
			*tail = next;
		}
	}
	strbuf_setlen(path, pathlen);

	for (i = 0; i < list.nr; i++)
		free(list.entries[i]);
	free(list.entries);

	return 0;
}

static int populate_opts_cb(const char *key, const char *value, void *data)
{
	struct replay_opts *opts = data;
	int error_flag = 1;

	if (!value)
		error_flag = 0;
	else if (!strcmp(key, "options.no-commit"))
		opts->no_commit = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.edit"))
		opts->edit = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.signoff"))
		opts->signoff = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.record-origin"))
		opts->record_origin = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.allow-ff"))
		opts->allow_ff = git_config_bool_or_int(key, value, &error_flag);
	else if (!strcmp(key, "options.mainline"))
		opts->mainline = git_config_int(key, value);
	else if (!strcmp(key, "options.strategy"))
		git_config_string(&opts->strategy, key, value);
	else if (!strcmp(key, "options.strategy-option")) {
		ALLOC_GROW(opts->xopts, opts->xopts_nr + 1, opts->xopts_alloc);
		opts->xopts[opts->xopts_nr++] = xstrdup(value);
	} else
		return error(_("Invalid key: %s"), key);

	if (!error_flag)
		return error(_("Invalid value for %s: %s"), key, value);

	return 0;
}

static struct dir_entry *dir_add_name(struct dir_struct *dir, const char *pathname, int len)
{
	if (cache_name_exists(pathname, len, ignore_case))
		return NULL;

	ALLOC_GROW(dir->entries, dir->nr+1, dir->alloc);
	return dir->entries[dir->nr++] = dir_entry_new(pathname, len);
}

void strbuf_grow(struct strbuf *sb, size_t extra)
{
	if (sb->len + extra + 1 <= sb->len)
		die("you want to use way too much memory");
	if (!sb->alloc)
		sb->buf = NULL;
	ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
}

static void add_to_ref_list(const unsigned char *sha1, const char *name,
		struct ref_list *list)
{
	ALLOC_GROW(list->list, list->nr + 1, list->alloc);
	hashcpy(list->list[list->nr].sha1, sha1);
	list->list[list->nr].name = xstrdup(name);
	list->nr++;
}

struct string_list_item *string_list_append(struct string_list *list, const char *string)
{
	ALLOC_GROW(list->items, list->nr + 1, list->alloc);
	list->items[list->nr].string =
		list->strdup_strings ? xstrdup(string) : (char *)string;
	list->items[list->nr].util = NULL;
	return list->items + list->nr++;
}

void set_dirpath(int wd, const char *path)
{
	int old_alloc = wd_alloc;
	ALLOC_GROW(wdpaths, wd+1, wd_alloc);
	if (old_alloc < wd_alloc)
		memset(wdpaths+old_alloc, 0,
		       (wd_alloc-old_alloc)*sizeof(const char *));
	wdpaths[wd] = strdup(path);
}

void add_rewritten(struct rewritten *list, unsigned char *from, unsigned char *to)
{
	struct rewritten_item *item;
	ALLOC_GROW(list->items, list->nr + 1, list->alloc);
	item = &list->items[list->nr];
	hashcpy(item->from, from);
	hashcpy(item->to, to);
	list->nr++;
}

static void add_header(const char *value)
{
	int len = strlen(value);
	while (len && value[len - 1] == '\n')
		len--;
	if (!strncasecmp(value, "to: ", 4)) {
		ALLOC_GROW(extra_to, extra_to_nr + 1, extra_to_alloc);
		extra_to[extra_to_nr++] = xstrndup(value + 4, len - 4);
		return;
	}
	if (!strncasecmp(value, "cc: ", 4)) {
		ALLOC_GROW(extra_cc, extra_cc_nr + 1, extra_cc_alloc);
		extra_cc[extra_cc_nr++] = xstrndup(value + 4, len - 4);
		return;
	}
	ALLOC_GROW(extra_hdr, extra_hdr_nr + 1, extra_hdr_alloc);
	extra_hdr[extra_hdr_nr++] = xstrndup(value, len);
}

static char *args_to_str(const char **argv)
{
	char *buf = NULL;
	unsigned long len, space = 0, nr = 0;

	for (; *argv; argv++) {
		len = strlen(*argv);
		ALLOC_GROW(buf, nr + 1 + len, space);
		if (nr)
			buf[nr++] = ' ';
		memcpy(buf + nr, *argv, len);
		nr += len;
	}
	ALLOC_GROW(buf, nr + 1, space);
	buf[nr] = '\0';

	return buf;
}

static struct ref_update *add_update(struct ref_transaction *transaction,
				     const char *refname)
{
	struct ref_update *update;
	FLEX_ALLOC_STR(update, refname, refname);
	ALLOC_GROW(transaction->updates, transaction->nr + 1, transaction->alloc);
	transaction->updates[transaction->nr++] = update;
	return update;
}

void strbuf_grow(struct strbuf *sb, size_t extra)
{
	int new_buf = !sb->alloc;
	if (new_buf)
		sb->buf = NULL;
	ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
	if (new_buf)
		sb->buf[0] = '\0';
}

void add_cmdname(struct cmdnames *cmds, const char *name, int len)
{
	struct cmdname *ent;
	FLEX_ALLOC_MEM(ent, name, name, len);
	ent->len = len;

	ALLOC_GROW(cmds->names, cmds->cnt + 1, cmds->alloc);
	cmds->names[cmds->cnt++] = ent;
}

void strbuf_grow(struct strbuf *sb, size_t extra)
{
	if (unsigned_add_overflows(extra, 1) ||
	    unsigned_add_overflows(sb->len, extra + 1))
		die("you want to use way too much memory");
	if (!sb->alloc)
		sb->buf = NULL;
	ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
}

int run_hook(const char *index_file, const char *name, ...)
{
	struct child_process hook;
	const char **argv = NULL, *env[2];
	char index[PATH_MAX];
	va_list args;
	int ret;
	size_t i = 0, alloc = 0;

	if (access(perf_path("hooks/%s", name), X_OK) < 0)
		return 0;

	va_start(args, name);
	ALLOC_GROW(argv, i + 1, alloc);
	argv[i++] = perf_path("hooks/%s", name);
	while (argv[i-1]) {
		ALLOC_GROW(argv, i + 1, alloc);
		argv[i++] = va_arg(args, const char *);
	}
	va_end(args);

	memset(&hook, 0, sizeof(hook));
	hook.argv = argv;
	hook.no_stdin = 1;
	hook.stdout_to_stderr = 1;
	if (index_file) {
		snprintf(index, sizeof(index), "PERF_INDEX_FILE=%s", index_file);
		env[0] = index;
		env[1] = NULL;
		hook.env = env;
	}

	ret = start_command(&hook);
	free(argv);
	if (ret) {
		warning("Could not spawn %s", argv[0]);
		return ret;
	}
	ret = finish_command(&hook);
	if (ret == -ERR_RUN_COMMAND_WAITPID_SIGNAL)
		warning("%s exited due to uncaught signal", argv[0]);

	return ret;
}

static int option_parse_x(const struct option *opt,
			  const char *arg, int unset)
{
	if (unset)
		return 0;

	ALLOC_GROW(xopts, xopts_nr + 1, xopts_alloc);
	xopts[xopts_nr++] = xstrdup(arg);
	return 0;
}

void hkl_tests_grow(struct hkl_tests * tests, size_t extra)
{
	if (tests->len + extra <= tests->len){
		fprintf(stderr, "you want to use way too much memory");
		exit(128);
	}
	if (!tests->alloc)
		tests->tests = NULL;
	ALLOC_GROW(tests->tests, tests->len + extra, tests->alloc);
}

static void add_cmd_list(struct cmdnames *cmds, struct cmdnames *old)
{
	int i;
	ALLOC_GROW(cmds->names, cmds->cnt + old->cnt, cmds->alloc);

	for (i = 0; i < old->cnt; i++)
		cmds->names[cmds->cnt++] = old->names[i];
	FREE_AND_NULL(old->names);
	old->cnt = 0;
}