merge(3p/git): Merge git subtree at v2.29.2 r/1890

This also bumps the stable nixpkgs to 20.09 as of 2020-11-21, because
there is some breakage in the git build related to the netrc
credentials helper which someone has taken care of in nixpkgs.

The stable channel is not used for anything other than git, so this
should be fine.

Change-Id: I3575a19dab09e1e9556cf8231d717de9890484fb

1 files changed, 385 insertions, 49 deletions

diff --git a/third_party/git/builtin/gc.c b/third_party/git/builtin/gc.c
index c18efadda53e..090959350e06 100644
--- a/third_party/git/builtin/gc.c
+++ b/third_party/git/builtin/gc.c
@@ -18,7 +18,7 @@
 #include "parse-options.h"
 #include "run-command.h"
 #include "sigchain.h"
-#include "argv-array.h"
+#include "strvec.h"
 #include "commit.h"
 #include "commit-graph.h"
 #include "packfile.h"
@@ -27,6 +27,8 @@
 #include "pack-objects.h"
 #include "blob.h"
 #include "tree.h"
+#include "promisor-remote.h"
+#include "refs.h"
 
 #define FAILED_RUN "failed to run %s"
 
@@ -41,7 +43,6 @@ static int aggressive_depth = 50;
 static int aggressive_window = 250;
 static int gc_auto_threshold = 6700;
 static int gc_auto_pack_limit = 50;
-static int gc_write_commit_graph;
 static int detach_auto = 1;
 static timestamp_t gc_log_expire_time;
 static const char *gc_log_expire = "1.day.ago";
@@ -50,12 +51,12 @@ static const char *prune_worktrees_expire = "3.months.ago";
 static unsigned long big_pack_threshold;
 static unsigned long max_delta_cache_size = DEFAULT_DELTA_CACHE_SIZE;
 
-static struct argv_array pack_refs_cmd = ARGV_ARRAY_INIT;
-static struct argv_array reflog = ARGV_ARRAY_INIT;
-static struct argv_array repack = ARGV_ARRAY_INIT;
-static struct argv_array prune = ARGV_ARRAY_INIT;
-static struct argv_array prune_worktrees = ARGV_ARRAY_INIT;
-static struct argv_array rerere = ARGV_ARRAY_INIT;
+static struct strvec pack_refs_cmd = STRVEC_INIT;
+static struct strvec reflog = STRVEC_INIT;
+static struct strvec repack = STRVEC_INIT;
+static struct strvec prune = STRVEC_INIT;
+static struct strvec prune_worktrees = STRVEC_INIT;
+static struct strvec rerere = STRVEC_INIT;
 
 static struct tempfile *pidfile;
 static struct lock_file log_lock;
@@ -148,7 +149,6 @@ static void gc_config(void)
 	git_config_get_int("gc.aggressivedepth", &aggressive_depth);
 	git_config_get_int("gc.auto", &gc_auto_threshold);
 	git_config_get_int("gc.autopacklimit", &gc_auto_pack_limit);
-	git_config_get_bool("gc.writecommitgraph", &gc_write_commit_graph);
 	git_config_get_bool("gc.autodetach", &detach_auto);
 	git_config_get_expiry("gc.pruneexpire", &prune_expire);
 	git_config_get_expiry("gc.worktreepruneexpire", &prune_worktrees_expire);
@@ -312,18 +312,18 @@ static uint64_t estimate_repack_memory(struct packed_git *pack)
 
 static int keep_one_pack(struct string_list_item *item, void *data)
 {
-	argv_array_pushf(&repack, "--keep-pack=%s", basename(item->string));
+	strvec_pushf(&repack, "--keep-pack=%s", basename(item->string));
 	return 0;
 }
 
 static void add_repack_all_option(struct string_list *keep_pack)
 {
 	if (prune_expire && !strcmp(prune_expire, "now"))
-		argv_array_push(&repack, "-a");
+		strvec_push(&repack, "-a");
 	else {
-		argv_array_push(&repack, "-A");
+		strvec_push(&repack, "-A");
 		if (prune_expire)
-			argv_array_pushf(&repack, "--unpack-unreachable=%s", prune_expire);
+			strvec_pushf(&repack, "--unpack-unreachable=%s", prune_expire);
 	}
 
 	if (keep_pack)
@@ -332,7 +332,7 @@ static void add_repack_all_option(struct string_list *keep_pack)
 
 static void add_repack_incremental_option(void)
 {
-	argv_array_push(&repack, "--no-write-bitmap-index");
+	strvec_push(&repack, "--no-write-bitmap-index");
 }
 
 static int need_to_gc(void)
@@ -459,7 +459,7 @@ static const char *lock_repo_for_gc(int force, pid_t* ret_pid)
 /*
  * Returns 0 if there was no previous error and gc can proceed, 1 if
  * gc should not proceed due to an error in the last run. Prints a
- * message and returns -1 if an error occured while reading gc.log
+ * message and returns -1 if an error occurred while reading gc.log
  */
 static int report_last_gc_error(void)
 {
@@ -515,11 +515,11 @@ static void gc_before_repack(void)
 	if (done++)
 		return;
 
-	if (pack_refs && run_command_v_opt(pack_refs_cmd.argv, RUN_GIT_CMD))
-		die(FAILED_RUN, pack_refs_cmd.argv[0]);
+	if (pack_refs && run_command_v_opt(pack_refs_cmd.v, RUN_GIT_CMD))
+		die(FAILED_RUN, pack_refs_cmd.v[0]);
 
-	if (prune_reflogs && run_command_v_opt(reflog.argv, RUN_GIT_CMD))
-		die(FAILED_RUN, reflog.argv[0]);
+	if (prune_reflogs && run_command_v_opt(reflog.v, RUN_GIT_CMD))
+		die(FAILED_RUN, reflog.v[0]);
 }
 
 int cmd_gc(int argc, const char **argv, const char *prefix)
@@ -553,12 +553,12 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 	if (argc == 2 && !strcmp(argv[1], "-h"))
 		usage_with_options(builtin_gc_usage, builtin_gc_options);
 
-	argv_array_pushl(&pack_refs_cmd, "pack-refs", "--all", "--prune", NULL);
-	argv_array_pushl(&reflog, "reflog", "expire", "--all", NULL);
-	argv_array_pushl(&repack, "repack", "-d", "-l", NULL);
-	argv_array_pushl(&prune, "prune", "--expire", NULL);
-	argv_array_pushl(&prune_worktrees, "worktree", "prune", "--expire", NULL);
-	argv_array_pushl(&rerere, "rerere", "gc", NULL);
+	strvec_pushl(&pack_refs_cmd, "pack-refs", "--all", "--prune", NULL);
+	strvec_pushl(&reflog, "reflog", "expire", "--all", NULL);
+	strvec_pushl(&repack, "repack", "-d", "-l", NULL);
+	strvec_pushl(&prune, "prune", "--expire", NULL);
+	strvec_pushl(&prune_worktrees, "worktree", "prune", "--expire", NULL);
+	strvec_pushl(&rerere, "rerere", "gc", NULL);
 
 	/* default expiry time, overwritten in gc_config */
 	gc_config();
@@ -577,14 +577,14 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 		die(_("failed to parse prune expiry value %s"), prune_expire);
 
 	if (aggressive) {
-		argv_array_push(&repack, "-f");
+		strvec_push(&repack, "-f");
 		if (aggressive_depth > 0)
-			argv_array_pushf(&repack, "--depth=%d", aggressive_depth);
+			strvec_pushf(&repack, "--depth=%d", aggressive_depth);
 		if (aggressive_window > 0)
-			argv_array_pushf(&repack, "--window=%d", aggressive_window);
+			strvec_pushf(&repack, "--window=%d", aggressive_window);
 	}
 	if (quiet)
-		argv_array_push(&repack, "-q");
+		strvec_push(&repack, "-q");
 
 	if (auto_gc) {
 		/*
@@ -602,7 +602,7 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 		if (detach_auto) {
 			int ret = report_last_gc_error();
 			if (ret < 0)
-				/* an I/O error occured, already reported */
+				/* an I/O error occurred, already reported */
 				exit(128);
 			if (ret == 1)
 				/* Last gc --auto failed. Skip this one. */
@@ -654,29 +654,29 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 
 	if (!repository_format_precious_objects) {
 		close_object_store(the_repository->objects);
-		if (run_command_v_opt(repack.argv, RUN_GIT_CMD))
-			die(FAILED_RUN, repack.argv[0]);
+		if (run_command_v_opt(repack.v, RUN_GIT_CMD))
+			die(FAILED_RUN, repack.v[0]);
 
 		if (prune_expire) {
-			argv_array_push(&prune, prune_expire);
+			strvec_push(&prune, prune_expire);
 			if (quiet)
-				argv_array_push(&prune, "--no-progress");
-			if (repository_format_partial_clone)
-				argv_array_push(&prune,
-						"--exclude-promisor-objects");
-			if (run_command_v_opt(prune.argv, RUN_GIT_CMD))
-				die(FAILED_RUN, prune.argv[0]);
+				strvec_push(&prune, "--no-progress");
+			if (has_promisor_remote())
+				strvec_push(&prune,
+					    "--exclude-promisor-objects");
+			if (run_command_v_opt(prune.v, RUN_GIT_CMD))
+				die(FAILED_RUN, prune.v[0]);
 		}
 	}
 
 	if (prune_worktrees_expire) {
-		argv_array_push(&prune_worktrees, prune_worktrees_expire);
-		if (run_command_v_opt(prune_worktrees.argv, RUN_GIT_CMD))
-			die(FAILED_RUN, prune_worktrees.argv[0]);
+		strvec_push(&prune_worktrees, prune_worktrees_expire);
+		if (run_command_v_opt(prune_worktrees.v, RUN_GIT_CMD))
+			die(FAILED_RUN, prune_worktrees.v[0]);
 	}
 
-	if (run_command_v_opt(rerere.argv, RUN_GIT_CMD))
-		die(FAILED_RUN, rerere.argv[0]);
+	if (run_command_v_opt(rerere.v, RUN_GIT_CMD))
+		die(FAILED_RUN, rerere.v[0]);
 
 	report_garbage = report_pack_garbage;
 	reprepare_packed_git(the_repository);
@@ -685,11 +685,11 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 		clean_pack_garbage();
 	}
 
-	if (gc_write_commit_graph &&
-	    write_commit_graph_reachable(get_object_directory(),
-					 !quiet && !daemonized ? COMMIT_GRAPH_PROGRESS : 0,
-					 NULL))
-		return 1;
+	prepare_repo_settings(the_repository);
+	if (the_repository->settings.gc_write_commit_graph == 1)
+		write_commit_graph_reachable(the_repository->objects->odb,
+					     !quiet && !daemonized ? COMMIT_GRAPH_WRITE_PROGRESS : 0,
+					     NULL);
 
 	if (auto_gc && too_many_loose_objects())
 		warning(_("There are too many unreachable loose objects; "
@@ -700,3 +700,339 @@ int cmd_gc(int argc, const char **argv, const char *prefix)
 
 	return 0;
 }
+
+static const char * const builtin_maintenance_run_usage[] = {
+	N_("git maintenance run [--auto] [--[no-]quiet] [--task=<task>]"),
+	NULL
+};
+
+struct maintenance_run_opts {
+	int auto_flag;
+	int quiet;
+};
+
+/* Remember to update object flag allocation in object.h */
+#define SEEN		(1u<<0)
+
+struct cg_auto_data {
+	int num_not_in_graph;
+	int limit;
+};
+
+static int dfs_on_ref(const char *refname,
+		      const struct object_id *oid, int flags,
+		      void *cb_data)
+{
+	struct cg_auto_data *data = (struct cg_auto_data *)cb_data;
+	int result = 0;
+	struct object_id peeled;
+	struct commit_list *stack = NULL;
+	struct commit *commit;
+
+	if (!peel_ref(refname, &peeled))
+		oid = &peeled;
+	if (oid_object_info(the_repository, oid, NULL) != OBJ_COMMIT)
+		return 0;
+
+	commit = lookup_commit(the_repository, oid);
+	if (!commit)
+		return 0;
+	if (parse_commit(commit))
+		return 0;
+
+	commit_list_append(commit, &stack);
+
+	while (!result && stack) {
+		struct commit_list *parent;
+
+		commit = pop_commit(&stack);
+
+		for (parent = commit->parents; parent; parent = parent->next) {
+			if (parse_commit(parent->item) ||
+			    commit_graph_position(parent->item) != COMMIT_NOT_FROM_GRAPH ||
+			    parent->item->object.flags & SEEN)
+				continue;
+
+			parent->item->object.flags |= SEEN;
+			data->num_not_in_graph++;
+
+			if (data->num_not_in_graph >= data->limit) {
+				result = 1;
+				break;
+			}
+
+			commit_list_append(parent->item, &stack);
+		}
+	}
+
+	free_commit_list(stack);
+	return result;
+}
+
+static int should_write_commit_graph(void)
+{
+	int result;
+	struct cg_auto_data data;
+
+	data.num_not_in_graph = 0;
+	data.limit = 100;
+	git_config_get_int("maintenance.commit-graph.auto",
+			   &data.limit);
+
+	if (!data.limit)
+		return 0;
+	if (data.limit < 0)
+		return 1;
+
+	result = for_each_ref(dfs_on_ref, &data);
+
+	clear_commit_marks_all(SEEN);
+
+	return result;
+}
+
+static int run_write_commit_graph(struct maintenance_run_opts *opts)
+{
+	struct child_process child = CHILD_PROCESS_INIT;
+
+	child.git_cmd = 1;
+	strvec_pushl(&child.args, "commit-graph", "write",
+		     "--split", "--reachable", NULL);
+
+	if (opts->quiet)
+		strvec_push(&child.args, "--no-progress");
+
+	return !!run_command(&child);
+}
+
+static int maintenance_task_commit_graph(struct maintenance_run_opts *opts)
+{
+	close_object_store(the_repository->objects);
+	if (run_write_commit_graph(opts)) {
+		error(_("failed to write commit-graph"));
+		return 1;
+	}
+
+	return 0;
+}
+
+static int maintenance_task_gc(struct maintenance_run_opts *opts)
+{
+	struct child_process child = CHILD_PROCESS_INIT;
+
+	child.git_cmd = 1;
+	strvec_push(&child.args, "gc");
+
+	if (opts->auto_flag)
+		strvec_push(&child.args, "--auto");
+	if (opts->quiet)
+		strvec_push(&child.args, "--quiet");
+	else
+		strvec_push(&child.args, "--no-quiet");
+
+	close_object_store(the_repository->objects);
+	return run_command(&child);
+}
+
+typedef int maintenance_task_fn(struct maintenance_run_opts *opts);
+
+/*
+ * An auto condition function returns 1 if the task should run
+ * and 0 if the task should NOT run. See needs_to_gc() for an
+ * example.
+ */
+typedef int maintenance_auto_fn(void);
+
+struct maintenance_task {
+	const char *name;
+	maintenance_task_fn *fn;
+	maintenance_auto_fn *auto_condition;
+	unsigned enabled:1;
+
+	/* -1 if not selected. */
+	int selected_order;
+};
+
+enum maintenance_task_label {
+	TASK_GC,
+	TASK_COMMIT_GRAPH,
+
+	/* Leave as final value */
+	TASK__COUNT
+};
+
+static struct maintenance_task tasks[] = {
+	[TASK_GC] = {
+		"gc",
+		maintenance_task_gc,
+		need_to_gc,
+		1,
+	},
+	[TASK_COMMIT_GRAPH] = {
+		"commit-graph",
+		maintenance_task_commit_graph,
+		should_write_commit_graph,
+	},
+};
+
+static int compare_tasks_by_selection(const void *a_, const void *b_)
+{
+	const struct maintenance_task *a, *b;
+
+	a = (const struct maintenance_task *)&a_;
+	b = (const struct maintenance_task *)&b_;
+
+	return b->selected_order - a->selected_order;
+}
+
+static int maintenance_run_tasks(struct maintenance_run_opts *opts)
+{
+	int i, found_selected = 0;
+	int result = 0;
+	struct lock_file lk;
+	struct repository *r = the_repository;
+	char *lock_path = xstrfmt("%s/maintenance", r->objects->odb->path);
+
+	if (hold_lock_file_for_update(&lk, lock_path, LOCK_NO_DEREF) < 0) {
+		/*
+		 * Another maintenance command is running.
+		 *
+		 * If --auto was provided, then it is likely due to a
+		 * recursive process stack. Do not report an error in
+		 * that case.
+		 */
+		if (!opts->auto_flag && !opts->quiet)
+			warning(_("lock file '%s' exists, skipping maintenance"),
+				lock_path);
+		free(lock_path);
+		return 0;
+	}
+	free(lock_path);
+
+	for (i = 0; !found_selected && i < TASK__COUNT; i++)
+		found_selected = tasks[i].selected_order >= 0;
+
+	if (found_selected)
+		QSORT(tasks, TASK__COUNT, compare_tasks_by_selection);
+
+	for (i = 0; i < TASK__COUNT; i++) {
+		if (found_selected && tasks[i].selected_order < 0)
+			continue;
+
+		if (!found_selected && !tasks[i].enabled)
+			continue;
+
+		if (opts->auto_flag &&
+		    (!tasks[i].auto_condition ||
+		     !tasks[i].auto_condition()))
+			continue;
+
+		trace2_region_enter("maintenance", tasks[i].name, r);
+		if (tasks[i].fn(opts)) {
+			error(_("task '%s' failed"), tasks[i].name);
+			result = 1;
+		}
+		trace2_region_leave("maintenance", tasks[i].name, r);
+	}
+
+	rollback_lock_file(&lk);
+	return result;
+}
+
+static void initialize_task_config(void)
+{
+	int i;
+	struct strbuf config_name = STRBUF_INIT;
+	gc_config();
+
+	for (i = 0; i < TASK__COUNT; i++) {
+		int config_value;
+
+		strbuf_setlen(&config_name, 0);
+		strbuf_addf(&config_name, "maintenance.%s.enabled",
+			    tasks[i].name);
+
+		if (!git_config_get_bool(config_name.buf, &config_value))
+			tasks[i].enabled = config_value;
+	}
+
+	strbuf_release(&config_name);
+}
+
+static int task_option_parse(const struct option *opt,
+			     const char *arg, int unset)
+{
+	int i, num_selected = 0;
+	struct maintenance_task *task = NULL;
+
+	BUG_ON_OPT_NEG(unset);
+
+	for (i = 0; i < TASK__COUNT; i++) {
+		if (tasks[i].selected_order >= 0)
+			num_selected++;
+		if (!strcasecmp(tasks[i].name, arg)) {
+			task = &tasks[i];
+		}
+	}
+
+	if (!task) {
+		error(_("'%s' is not a valid task"), arg);
+		return 1;
+	}
+
+	if (task->selected_order >= 0) {
+		error(_("task '%s' cannot be selected multiple times"), arg);
+		return 1;
+	}
+
+	task->selected_order = num_selected + 1;
+
+	return 0;
+}
+
+static int maintenance_run(int argc, const char **argv, const char *prefix)
+{
+	int i;
+	struct maintenance_run_opts opts;
+	struct option builtin_maintenance_run_options[] = {
+		OPT_BOOL(0, "auto", &opts.auto_flag,
+			 N_("run tasks based on the state of the repository")),
+		OPT_BOOL(0, "quiet", &opts.quiet,
+			 N_("do not report progress or other information over stderr")),
+		OPT_CALLBACK_F(0, "task", NULL, N_("task"),
+			N_("run a specific task"),
+			PARSE_OPT_NONEG, task_option_parse),
+		OPT_END()
+	};
+	memset(&opts, 0, sizeof(opts));
+
+	opts.quiet = !isatty(2);
+	initialize_task_config();
+
+	for (i = 0; i < TASK__COUNT; i++)
+		tasks[i].selected_order = -1;
+
+	argc = parse_options(argc, argv, prefix,
+			     builtin_maintenance_run_options,
+			     builtin_maintenance_run_usage,
+			     PARSE_OPT_STOP_AT_NON_OPTION);
+
+	if (argc != 0)
+		usage_with_options(builtin_maintenance_run_usage,
+				   builtin_maintenance_run_options);
+	return maintenance_run_tasks(&opts);
+}
+
+static const char builtin_maintenance_usage[] = N_("git maintenance run [<options>]");
+
+int cmd_maintenance(int argc, const char **argv, const char *prefix)
+{
+	if (argc < 2 ||
+	    (argc == 2 && !strcmp(argv[1], "-h")))
+		usage(builtin_maintenance_usage);
+
+	if (!strcmp(argv[1], "run"))
+		return maintenance_run(argc - 1, argv + 1, prefix);
+
+	die(_("invalid subcommand: %s"), argv[1]);
+}