1 files changed, 370 insertions, 0 deletions
diff --git a/third_party/git/list-objects-filter-options.c b/third_party/git/list-objects-filter-options.c
new file mode 100644
index 000000000000..256bcfbdfe66
--- /dev/null
+++ b/third_party/git/list-objects-filter-options.c
@@ -0,0 +1,370 @@
+#include "cache.h"
+#include "commit.h"
+#include "config.h"
+#include "revision.h"
+#include "argv-array.h"
+#include "list-objects.h"
+#include "list-objects-filter.h"
+#include "list-objects-filter-options.h"
+#include "promisor-remote.h"
+#include "trace.h"
+#include "url.h"
+
+static int parse_combine_filter(
+	struct list_objects_filter_options *filter_options,
+	const char *arg,
+	struct strbuf *errbuf);
+
+/*
+ * Parse value of the argument to the "filter" keyword.
+ * On the command line this looks like:
+ *       --filter=<arg>
+ * and in the pack protocol as:
+ *       "filter" SP <arg>
+ *
+ * The filter keyword will be used by many commands.
+ * See Documentation/rev-list-options.txt for allowed values for <arg>.
+ *
+ * Capture the given arg as the "filter_spec".  This can be forwarded to
+ * subordinate commands when necessary (although it's better to pass it through
+ * expand_list_objects_filter_spec() first).  We also "intern" the arg for the
+ * convenience of the current command.
+ */
+static int gently_parse_list_objects_filter(
+	struct list_objects_filter_options *filter_options,
+	const char *arg,
+	struct strbuf *errbuf)
+{
+	const char *v0;
+
+	if (!arg)
+		return 0;
+
+	if (filter_options->choice)
+		BUG("filter_options already populated");
+
+	if (!strcmp(arg, "blob:none")) {
+		filter_options->choice = LOFC_BLOB_NONE;
+		return 0;
+
+	} else if (skip_prefix(arg, "blob:limit=", &v0)) {
+		if (git_parse_ulong(v0, &filter_options->blob_limit_value)) {
+			filter_options->choice = LOFC_BLOB_LIMIT;
+			return 0;
+		}
+
+	} else if (skip_prefix(arg, "tree:", &v0)) {
+		if (!git_parse_ulong(v0, &filter_options->tree_exclude_depth)) {
+			strbuf_addstr(errbuf, _("expected 'tree:<depth>'"));
+			return 1;
+		}
+		filter_options->choice = LOFC_TREE_DEPTH;
+		return 0;
+
+	} else if (skip_prefix(arg, "sparse:oid=", &v0)) {
+		filter_options->sparse_oid_name = xstrdup(v0);
+		filter_options->choice = LOFC_SPARSE_OID;
+		return 0;
+
+	} else if (skip_prefix(arg, "sparse:path=", &v0)) {
+		if (errbuf) {
+			strbuf_addstr(
+				errbuf,
+				_("sparse:path filters support has been dropped"));
+		}
+		return 1;
+
+	} else if (skip_prefix(arg, "combine:", &v0)) {
+		return parse_combine_filter(filter_options, v0, errbuf);
+
+	}
+	/*
+	 * Please update _git_fetch() in git-completion.bash when you
+	 * add new filters
+	 */
+
+	strbuf_addf(errbuf, _("invalid filter-spec '%s'"), arg);
+
+	memset(filter_options, 0, sizeof(*filter_options));
+	return 1;
+}
+
+static const char *RESERVED_NON_WS = "~`!@#$^&*()[]{}\\;'\",<>?";
+
+static int has_reserved_character(
+	struct strbuf *sub_spec, struct strbuf *errbuf)
+{
+	const char *c = sub_spec->buf;
+	while (*c) {
+		if (*c <= ' ' || strchr(RESERVED_NON_WS, *c)) {
+			strbuf_addf(
+				errbuf,
+				_("must escape char in sub-filter-spec: '%c'"),
+				*c);
+			return 1;
+		}
+		c++;
+	}
+
+	return 0;
+}
+
+static int parse_combine_subfilter(
+	struct list_objects_filter_options *filter_options,
+	struct strbuf *subspec,
+	struct strbuf *errbuf)
+{
+	size_t new_index = filter_options->sub_nr;
+	char *decoded;
+	int result;
+
+	ALLOC_GROW_BY(filter_options->sub, filter_options->sub_nr, 1,
+		      filter_options->sub_alloc);
+
+	decoded = url_percent_decode(subspec->buf);
+
+	result = has_reserved_character(subspec, errbuf) ||
+		gently_parse_list_objects_filter(
+			&filter_options->sub[new_index], decoded, errbuf);
+
+	free(decoded);
+	return result;
+}
+
+static int parse_combine_filter(
+	struct list_objects_filter_options *filter_options,
+	const char *arg,
+	struct strbuf *errbuf)
+{
+	struct strbuf **subspecs = strbuf_split_str(arg, '+', 0);
+	size_t sub;
+	int result = 0;
+
+	if (!subspecs[0]) {
+		strbuf_addstr(errbuf, _("expected something after combine:"));
+		result = 1;
+		goto cleanup;
+	}
+
+	for (sub = 0; subspecs[sub] && !result; sub++) {
+		if (subspecs[sub + 1]) {
+			/*
+			 * This is not the last subspec. Remove trailing "+" so
+			 * we can parse it.
+			 */
+			size_t last = subspecs[sub]->len - 1;
+			assert(subspecs[sub]->buf[last] == '+');
+			strbuf_remove(subspecs[sub], last, 1);
+		}
+		result = parse_combine_subfilter(
+			filter_options, subspecs[sub], errbuf);
+	}
+
+	filter_options->choice = LOFC_COMBINE;
+
+cleanup:
+	strbuf_list_free(subspecs);
+	if (result) {
+		list_objects_filter_release(filter_options);
+		memset(filter_options, 0, sizeof(*filter_options));
+	}
+	return result;
+}
+
+static int allow_unencoded(char ch)
+{
+	if (ch <= ' ' || ch == '%' || ch == '+')
+		return 0;
+	return !strchr(RESERVED_NON_WS, ch);
+}
+
+static void filter_spec_append_urlencode(
+	struct list_objects_filter_options *filter, const char *raw)
+{
+	struct strbuf buf = STRBUF_INIT;
+	strbuf_addstr_urlencode(&buf, raw, allow_unencoded);
+	trace_printf("Add to combine filter-spec: %s\n", buf.buf);
+	string_list_append(&filter->filter_spec, strbuf_detach(&buf, NULL));
+}
+
+/*
+ * Changes filter_options into an equivalent LOFC_COMBINE filter options
+ * instance. Does not do anything if filter_options is already LOFC_COMBINE.
+ */
+static void transform_to_combine_type(
+	struct list_objects_filter_options *filter_options)
+{
+	assert(filter_options->choice);
+	if (filter_options->choice == LOFC_COMBINE)
+		return;
+	{
+		const int initial_sub_alloc = 2;
+		struct list_objects_filter_options *sub_array =
+			xcalloc(initial_sub_alloc, sizeof(*sub_array));
+		sub_array[0] = *filter_options;
+		memset(filter_options, 0, sizeof(*filter_options));
+		filter_options->sub = sub_array;
+		filter_options->sub_alloc = initial_sub_alloc;
+	}
+	filter_options->sub_nr = 1;
+	filter_options->choice = LOFC_COMBINE;
+	string_list_append(&filter_options->filter_spec, xstrdup("combine:"));
+	filter_spec_append_urlencode(
+		filter_options,
+		list_objects_filter_spec(&filter_options->sub[0]));
+	/*
+	 * We don't need the filter_spec strings for subfilter specs, only the
+	 * top level.
+	 */
+	string_list_clear(&filter_options->sub[0].filter_spec, /*free_util=*/0);
+}
+
+void list_objects_filter_die_if_populated(
+	struct list_objects_filter_options *filter_options)
+{
+	if (filter_options->choice)
+		die(_("multiple filter-specs cannot be combined"));
+}
+
+void parse_list_objects_filter(
+	struct list_objects_filter_options *filter_options,
+	const char *arg)
+{
+	struct strbuf errbuf = STRBUF_INIT;
+	int parse_error;
+
+	if (!filter_options->choice) {
+		string_list_append(&filter_options->filter_spec, xstrdup(arg));
+
+		parse_error = gently_parse_list_objects_filter(
+			filter_options, arg, &errbuf);
+	} else {
+		/*
+		 * Make filter_options an LOFC_COMBINE spec so we can trivially
+		 * add subspecs to it.
+		 */
+		transform_to_combine_type(filter_options);
+
+		string_list_append(&filter_options->filter_spec, xstrdup("+"));
+		filter_spec_append_urlencode(filter_options, arg);
+		ALLOC_GROW_BY(filter_options->sub, filter_options->sub_nr, 1,
+			      filter_options->sub_alloc);
+
+		parse_error = gently_parse_list_objects_filter(
+			&filter_options->sub[filter_options->sub_nr - 1], arg,
+			&errbuf);
+	}
+	if (parse_error)
+		die("%s", errbuf.buf);
+}
+
+int opt_parse_list_objects_filter(const struct option *opt,
+				  const char *arg, int unset)
+{
+	struct list_objects_filter_options *filter_options = opt->value;
+
+	if (unset || !arg)
+		list_objects_filter_set_no_filter(filter_options);
+	else
+		parse_list_objects_filter(filter_options, arg);
+	return 0;
+}
+
+const char *list_objects_filter_spec(struct list_objects_filter_options *filter)
+{
+	if (!filter->filter_spec.nr)
+		BUG("no filter_spec available for this filter");
+	if (filter->filter_spec.nr != 1) {
+		struct strbuf concatted = STRBUF_INIT;
+		strbuf_add_separated_string_list(
+			&concatted, "", &filter->filter_spec);
+		string_list_clear(&filter->filter_spec, /*free_util=*/0);
+		string_list_append(
+			&filter->filter_spec, strbuf_detach(&concatted, NULL));
+	}
+
+	return filter->filter_spec.items[0].string;
+}
+
+const char *expand_list_objects_filter_spec(
+	struct list_objects_filter_options *filter)
+{
+	if (filter->choice == LOFC_BLOB_LIMIT) {
+		struct strbuf expanded_spec = STRBUF_INIT;
+		strbuf_addf(&expanded_spec, "blob:limit=%lu",
+			    filter->blob_limit_value);
+		string_list_clear(&filter->filter_spec, /*free_util=*/0);
+		string_list_append(
+			&filter->filter_spec,
+			strbuf_detach(&expanded_spec, NULL));
+	}
+
+	return list_objects_filter_spec(filter);
+}
+
+void list_objects_filter_release(
+	struct list_objects_filter_options *filter_options)
+{
+	size_t sub;
+
+	if (!filter_options)
+		return;
+	string_list_clear(&filter_options->filter_spec, /*free_util=*/0);
+	free(filter_options->sparse_oid_name);
+	for (sub = 0; sub < filter_options->sub_nr; sub++)
+		list_objects_filter_release(&filter_options->sub[sub]);
+	free(filter_options->sub);
+	memset(filter_options, 0, sizeof(*filter_options));
+}
+
+void partial_clone_register(
+	const char *remote,
+	struct list_objects_filter_options *filter_options)
+{
+	char *cfg_name;
+	char *filter_name;
+
+	/* Check if it is already registered */
+	if (!promisor_remote_find(remote)) {
+		git_config_set("core.repositoryformatversion", "1");
+
+		/* Add promisor config for the remote */
+		cfg_name = xstrfmt("remote.%s.promisor", remote);
+		git_config_set(cfg_name, "true");
+		free(cfg_name);
+	}
+
+	/*
+	 * Record the initial filter-spec in the config as
+	 * the default for subsequent fetches from this remote.
+	 */
+	filter_name = xstrfmt("remote.%s.partialclonefilter", remote);
+	/* NEEDSWORK: 'expand' result leaking??? */
+	git_config_set(filter_name,
+		       expand_list_objects_filter_spec(filter_options));
+	free(filter_name);
+
+	/* Make sure the config info are reset */
+	promisor_remote_reinit();
+}
+
+void partial_clone_get_default_filter_spec(
+	struct list_objects_filter_options *filter_options,
+	const char *remote)
+{
+	struct promisor_remote *promisor = promisor_remote_find(remote);
+	struct strbuf errbuf = STRBUF_INIT;
+
+	/*
+	 * Parse default value, but silently ignore it if it is invalid.
+	 */
+	if (!promisor)
+		return;
+
+	string_list_append(&filter_options->filter_spec,
+			   promisor->partial_clone_filter);
+	gently_parse_list_objects_filter(filter_options,
+					 promisor->partial_clone_filter,
+					 &errbuf);
+	strbuf_release(&errbuf);
+}