builtin/read-tree.c - jrn/git - Git at Google

 /*
  * GIT - The information manager from hell
  *
  * Copyright (C) Linus Torvalds, 2005
  */

 #include "cache.h"
 #include "lockfile.h"
 #include "object.h"
 #include "tree.h"
 #include "tree-walk.h"
 #include "cache-tree.h"
 #include "unpack-trees.h"
 #include "dir.h"
 #include "builtin.h"
 #include "parse-options.h"
 #include "resolve-undo.h"
 #include "submodule.h"
 #include "submodule-config.h"

 static int nr_trees;
 static int read_empty;
 static struct tree *trees[MAX_UNPACK_TREES];
 static int recurse_submodules = RECURSE_SUBMODULES_DEFAULT;

 static int list_tree(unsigned char *sha1)
 {
 	struct tree *tree;

 	if (nr_trees >= MAX_UNPACK_TREES)
 		die("I cannot read more than %d trees", MAX_UNPACK_TREES);
 	tree = parse_tree_indirect(sha1);
 	if (!tree)
 		return -1;
 	trees[nr_trees++] = tree;
 	return 0;
 }

 static const char * const read_tree_usage[] = {
 	N_("git read-tree [(-m [--trivial] [--aggressive] | --reset | --prefix=<prefix>) [-u [--exclude-per-directory=<gitignore>] | -i]] [--no-sparse-checkout] [--index-output=<file>] (--empty | <tree-ish1> [<tree-ish2> [<tree-ish3>]])"),
 	NULL
 };

 static int index_output_cb(const struct option *opt, const char *arg,
 				 int unset)
 {
 	set_alternate_index_output(arg);
 	return 0;
 }

 static int exclude_per_directory_cb(const struct option *opt, const char *arg,
 				    int unset)
 {
 	struct dir_struct *dir;
 	struct unpack_trees_options *opts;

 	opts = (struct unpack_trees_options *)opt->value;

 	if (opts->dir)
 		die("more than one --exclude-per-directory given.");

 	dir = xcalloc(1, sizeof(*opts->dir));
 	dir->flags |= DIR_SHOW_IGNORED;
 	dir->exclude_per_dir = arg;
 	opts->dir = dir;
 	/* We do not need to nor want to do read-directory
 	 * here; we are merely interested in reusing the
 	 * per directory ignore stack mechanism.
 	 */
 	return 0;
 }

 static void debug_stage(const char *label, const struct cache_entry *ce,
 			struct unpack_trees_options *o)
 {
 	printf("%s ", label);
 	if (!ce)
 		printf("(missing)\n");
 	else if (ce == o->df_conflict_entry)
 		printf("(conflict)\n");
 	else
 		printf("%06o #%d %s %.8s\n",
 		       ce->ce_mode, ce_stage(ce), ce->name,
 		       oid_to_hex(&ce->oid));
 }

 static int debug_merge(const struct cache_entry * const *stages,
 		       struct unpack_trees_options *o)
 {
 	int i;

 	printf("* %d-way merge\n", o->merge_size);
 	debug_stage("index", stages[0], o);
 	for (i = 1; i <= o->merge_size; i++) {
 		char buf[24];
 		xsnprintf(buf, sizeof(buf), "ent#%d", i);
 		debug_stage(buf, stages[i], o);
 	}
 	return 0;
 }

 static int option_parse_recurse_submodules(const struct option *opt,
 					   const char *arg, int unset)
 {
 	if (unset) {
 		recurse_submodules = RECURSE_SUBMODULES_OFF;
 		return 0;
 	}
 	if (arg)
 		recurse_submodules =
 			parse_update_recurse_submodules_arg(opt->long_name,
 							    arg);
 	else
 		recurse_submodules = RECURSE_SUBMODULES_ON;

 	return 0;
 }

 static struct lock_file lock_file;

 int cmd_read_tree(int argc, const char **argv, const char *unused_prefix)
 {
 	int i, stage = 0;
 	unsigned char sha1[20];
 	struct tree_desc t[MAX_UNPACK_TREES];
 	struct unpack_trees_options opts;
 	int prefix_set = 0;
 	const struct option read_tree_options[] = {
 		{ OPTION_CALLBACK, 0, "index-output", NULL, N_("file"),
 		  N_("write resulting index to <file>"),
 		  PARSE_OPT_NONEG, index_output_cb },
 		OPT_BOOL(0, "empty", &read_empty,
 			    N_("only empty the index")),
 		OPT__VERBOSE(&opts.verbose_update, N_("be verbose")),
 		OPT_GROUP(N_("Merging")),
 		OPT_BOOL('m', NULL, &opts.merge,
 			 N_("perform a merge in addition to a read")),
 		OPT_BOOL(0, "trivial", &opts.trivial_merges_only,
 			 N_("3-way merge if no file level merging required")),
 		OPT_BOOL(0, "aggressive", &opts.aggressive,
 			 N_("3-way merge in presence of adds and removes")),
 		OPT_BOOL(0, "reset", &opts.reset,
 			 N_("same as -m, but discard unmerged entries")),
 		{ OPTION_STRING, 0, "prefix", &opts.prefix, N_("<subdirectory>/"),
 		  N_("read the tree into the index under <subdirectory>/"),
 		  PARSE_OPT_NONEG | PARSE_OPT_LITERAL_ARGHELP },
 		OPT_BOOL('u', NULL, &opts.update,
 			 N_("update working tree with merge result")),
 		{ OPTION_CALLBACK, 0, "exclude-per-directory", &opts,
 		  N_("gitignore"),
 		  N_("allow explicitly ignored files to be overwritten"),
 		  PARSE_OPT_NONEG, exclude_per_directory_cb },
 		OPT_BOOL('i', NULL, &opts.index_only,
 			 N_("don't check the working tree after merging")),
 		OPT__DRY_RUN(&opts.dry_run, N_("don't update the index or the work tree")),
 		OPT_BOOL(0, "no-sparse-checkout", &opts.skip_sparse_checkout,
 			 N_("skip applying sparse checkout filter")),
 		OPT_BOOL(0, "debug-unpack", &opts.debug_unpack,
 			 N_("debug unpack-trees")),
 		{ OPTION_CALLBACK, 0, "recurse-submodules", &recurse_submodules,
 			    "checkout", "control recursive updating of submodules",
 			    PARSE_OPT_OPTARG, option_parse_recurse_submodules },
 		OPT_END()
 	};

 	memset(&opts, 0, sizeof(opts));
 	opts.head_idx = -1;
 	opts.src_index = &the_index;
 	opts.dst_index = &the_index;

 	git_config(git_default_config, NULL);

 	argc = parse_options(argc, argv, unused_prefix, read_tree_options,
 			     read_tree_usage, 0);

 	hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);

 	if (recurse_submodules != RECURSE_SUBMODULES_DEFAULT) {
 		gitmodules_config();
 		git_config(submodule_config, NULL);
 		set_config_update_recurse_submodules(RECURSE_SUBMODULES_ON);
 	}

 	prefix_set = opts.prefix ? 1 : 0;
 	if (1 < opts.merge + opts.reset + prefix_set)
 		die("Which one? -m, --reset, or --prefix?");

 	/*
 	 * NEEDSWORK
 	 *
 	 * The old index should be read anyway even if we're going to
 	 * destroy all index entries because we still need to preserve
 	 * certain information such as index version or split-index
 	 * mode.
 	 */

 	if (opts.reset || opts.merge || opts.prefix) {
 		if (read_cache_unmerged() && (opts.prefix || opts.merge))
 			die("You need to resolve your current index first");
 		stage = opts.merge = 1;
 	}
 	resolve_undo_clear();

 	for (i = 0; i < argc; i++) {
 		const char *arg = argv[i];

 		if (get_sha1(arg, sha1))
 			die("Not a valid object name %s", arg);
 		if (list_tree(sha1) < 0)
 			die("failed to unpack tree object %s", arg);
 		stage++;
 	}
 	if (!nr_trees && !read_empty && !opts.merge)
 		warning("read-tree: emptying the index with no arguments is deprecated; use --empty");
 	else if (nr_trees > 0 && read_empty)
 		die("passing trees as arguments contradicts --empty");

 	if (1 < opts.index_only + opts.update)
 		die("-u and -i at the same time makes no sense");
 	if ((opts.update || opts.index_only) && !opts.merge)
 		die("%s is meaningless without -m, --reset, or --prefix",
 		    opts.update ? "-u" : "-i");
 	if ((opts.dir && !opts.update))
 		die("--exclude-per-directory is meaningless unless -u");
 	if (opts.merge && !opts.index_only)
 		setup_work_tree();

 	if (opts.merge) {
 		switch (stage - 1) {
 		case 0:
 			die("you must specify at least one tree to merge");
 			break;
 		case 1:
 			opts.fn = opts.prefix ? bind_merge : oneway_merge;
 			break;
 		case 2:
 			opts.fn = twoway_merge;
 			opts.initial_checkout = is_cache_unborn();
 			break;
 		case 3:
 		default:
 			opts.fn = threeway_merge;
 			break;
 		}

 		if (stage - 1 >= 3)
 			opts.head_idx = stage - 2;
 		else
 			opts.head_idx = 1;
 	}

 	if (opts.debug_unpack)
 		opts.fn = debug_merge;

 	cache_tree_free(&active_cache_tree);
 	for (i = 0; i < nr_trees; i++) {
 		struct tree *tree = trees[i];
 		parse_tree(tree);
 		init_tree_desc(t+i, tree->buffer, tree->size);
 	}
 	if (unpack_trees(nr_trees, t, &opts))
 		return 128;

 	if (opts.debug_unpack || opts.dry_run)
 		return 0; /* do not write the index out */

 	/*
 	 * When reading only one tree (either the most basic form,
 	 * "-m ent" or "--reset ent" form), we can obtain a fully
 	 * valid cache-tree because the index must match exactly
 	 * what came from the tree.
 	 */
 	if (nr_trees == 1 && !opts.prefix)
 		prime_cache_tree(&the_index, trees[0]);

 	if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
 		die("unable to write new index file");
 	return 0;
 }
	/*
	* GIT - The information manager from hell
	*
	* Copyright (C) Linus Torvalds, 2005
	*/

	#include "cache.h"
	#include "lockfile.h"
	#include "object.h"
	#include "tree.h"
	#include "tree-walk.h"
	#include "cache-tree.h"
	#include "unpack-trees.h"
	#include "dir.h"
	#include "builtin.h"
	#include "parse-options.h"
	#include "resolve-undo.h"
	#include "submodule.h"
	#include "submodule-config.h"

	static int nr_trees;
	static int read_empty;
	static struct tree *trees[MAX_UNPACK_TREES];
	static int recurse_submodules = RECURSE_SUBMODULES_DEFAULT;

	static int list_tree(unsigned char *sha1)
	{
	struct tree *tree;

	if (nr_trees >= MAX_UNPACK_TREES)
	die("I cannot read more than %d trees", MAX_UNPACK_TREES);
	tree = parse_tree_indirect(sha1);
	if (!tree)
	return -1;
	trees[nr_trees++] = tree;
	return 0;
	}

	static const char * const read_tree_usage[] = {
	N_("git read-tree [(-m [--trivial] [--aggressive] \| --reset \| --prefix=<prefix>) [-u [--exclude-per-directory=<gitignore>] \| -i]] [--no-sparse-checkout] [--index-output=<file>] (--empty \| <tree-ish1> [<tree-ish2> [<tree-ish3>]])"),
	NULL
	};

	static int index_output_cb(const struct option opt, const char arg,
	int unset)
	{
	set_alternate_index_output(arg);
	return 0;
	}

	static int exclude_per_directory_cb(const struct option opt, const char arg,
	int unset)
	{
	struct dir_struct *dir;
	struct unpack_trees_options *opts;

	opts = (struct unpack_trees_options *)opt->value;

	if (opts->dir)
	die("more than one --exclude-per-directory given.");

	dir = xcalloc(1, sizeof(*opts->dir));
	dir->flags \|= DIR_SHOW_IGNORED;
	dir->exclude_per_dir = arg;
	opts->dir = dir;
	/* We do not need to nor want to do read-directory
	* here; we are merely interested in reusing the
	* per directory ignore stack mechanism.
	*/
	return 0;
	}

	static void debug_stage(const char label, const struct cache_entry ce,
	struct unpack_trees_options *o)
	{
	printf("%s ", label);
	if (!ce)
	printf("(missing)\n");
	else if (ce == o->df_conflict_entry)
	printf("(conflict)\n");
	else
	printf("%06o #%d %s %.8s\n",
	ce->ce_mode, ce_stage(ce), ce->name,
	oid_to_hex(&ce->oid));
	}

	static int debug_merge(const struct cache_entry * const *stages,
	struct unpack_trees_options *o)
	{
	int i;

	printf("* %d-way merge\n", o->merge_size);
	debug_stage("index", stages[0], o);
	for (i = 1; i <= o->merge_size; i++) {
	char buf[24];
	xsnprintf(buf, sizeof(buf), "ent#%d", i);
	debug_stage(buf, stages[i], o);
	}
	return 0;
	}

	static int option_parse_recurse_submodules(const struct option *opt,
	const char *arg, int unset)
	{
	if (unset) {
	recurse_submodules = RECURSE_SUBMODULES_OFF;
	return 0;
	}
	if (arg)
	recurse_submodules =
	parse_update_recurse_submodules_arg(opt->long_name,
	arg);
	else
	recurse_submodules = RECURSE_SUBMODULES_ON;

	return 0;
	}

	static struct lock_file lock_file;

	int cmd_read_tree(int argc, const char *argv, const char unused_prefix)
	{
	int i, stage = 0;
	unsigned char sha1[20];
	struct tree_desc t[MAX_UNPACK_TREES];
	struct unpack_trees_options opts;
	int prefix_set = 0;
	const struct option read_tree_options[] = {
	{ OPTION_CALLBACK, 0, "index-output", NULL, N_("file"),
	N_("write resulting index to <file>"),
	PARSE_OPT_NONEG, index_output_cb },
	OPT_BOOL(0, "empty", &read_empty,
	N_("only empty the index")),
	OPT__VERBOSE(&opts.verbose_update, N_("be verbose")),
	OPT_GROUP(N_("Merging")),
	OPT_BOOL('m', NULL, &opts.merge,
	N_("perform a merge in addition to a read")),
	OPT_BOOL(0, "trivial", &opts.trivial_merges_only,
	N_("3-way merge if no file level merging required")),
	OPT_BOOL(0, "aggressive", &opts.aggressive,
	N_("3-way merge in presence of adds and removes")),
	OPT_BOOL(0, "reset", &opts.reset,
	N_("same as -m, but discard unmerged entries")),
	{ OPTION_STRING, 0, "prefix", &opts.prefix, N_("<subdirectory>/"),
	N_("read the tree into the index under <subdirectory>/"),
	PARSE_OPT_NONEG \| PARSE_OPT_LITERAL_ARGHELP },
	OPT_BOOL('u', NULL, &opts.update,
	N_("update working tree with merge result")),
	{ OPTION_CALLBACK, 0, "exclude-per-directory", &opts,
	N_("gitignore"),
	N_("allow explicitly ignored files to be overwritten"),
	PARSE_OPT_NONEG, exclude_per_directory_cb },
	OPT_BOOL('i', NULL, &opts.index_only,
	N_("don't check the working tree after merging")),
	OPT__DRY_RUN(&opts.dry_run, N_("don't update the index or the work tree")),
	OPT_BOOL(0, "no-sparse-checkout", &opts.skip_sparse_checkout,
	N_("skip applying sparse checkout filter")),
	OPT_BOOL(0, "debug-unpack", &opts.debug_unpack,
	N_("debug unpack-trees")),
	{ OPTION_CALLBACK, 0, "recurse-submodules", &recurse_submodules,
	"checkout", "control recursive updating of submodules",
	PARSE_OPT_OPTARG, option_parse_recurse_submodules },
	OPT_END()
	};

	memset(&opts, 0, sizeof(opts));
	opts.head_idx = -1;
	opts.src_index = &the_index;
	opts.dst_index = &the_index;

	git_config(git_default_config, NULL);

	argc = parse_options(argc, argv, unused_prefix, read_tree_options,
	read_tree_usage, 0);

	hold_locked_index(&lock_file, LOCK_DIE_ON_ERROR);

	if (recurse_submodules != RECURSE_SUBMODULES_DEFAULT) {
	gitmodules_config();
	git_config(submodule_config, NULL);
	set_config_update_recurse_submodules(RECURSE_SUBMODULES_ON);
	}

	prefix_set = opts.prefix ? 1 : 0;
	if (1 < opts.merge + opts.reset + prefix_set)
	die("Which one? -m, --reset, or --prefix?");

	/*
	* NEEDSWORK
	*
	* The old index should be read anyway even if we're going to
	* destroy all index entries because we still need to preserve
	* certain information such as index version or split-index
	* mode.
	*/

	if (opts.reset \|\| opts.merge \|\| opts.prefix) {
	if (read_cache_unmerged() && (opts.prefix \|\| opts.merge))
	die("You need to resolve your current index first");
	stage = opts.merge = 1;
	}
	resolve_undo_clear();

	for (i = 0; i < argc; i++) {
	const char *arg = argv[i];

	if (get_sha1(arg, sha1))
	die("Not a valid object name %s", arg);
	if (list_tree(sha1) < 0)
	die("failed to unpack tree object %s", arg);
	stage++;
	}
	if (!nr_trees && !read_empty && !opts.merge)
	warning("read-tree: emptying the index with no arguments is deprecated; use --empty");
	else if (nr_trees > 0 && read_empty)
	die("passing trees as arguments contradicts --empty");

	if (1 < opts.index_only + opts.update)
	die("-u and -i at the same time makes no sense");
	if ((opts.update \|\| opts.index_only) && !opts.merge)
	die("%s is meaningless without -m, --reset, or --prefix",
	opts.update ? "-u" : "-i");
	if ((opts.dir && !opts.update))
	die("--exclude-per-directory is meaningless unless -u");
	if (opts.merge && !opts.index_only)
	setup_work_tree();

	if (opts.merge) {
	switch (stage - 1) {
	case 0:
	die("you must specify at least one tree to merge");
	break;
	case 1:
	opts.fn = opts.prefix ? bind_merge : oneway_merge;
	break;
	case 2:
	opts.fn = twoway_merge;
	opts.initial_checkout = is_cache_unborn();
	break;
	case 3:
	default:
	opts.fn = threeway_merge;
	break;
	}

	if (stage - 1 >= 3)
	opts.head_idx = stage - 2;
	else
	opts.head_idx = 1;
	}

	if (opts.debug_unpack)
	opts.fn = debug_merge;

	cache_tree_free(&active_cache_tree);
	for (i = 0; i < nr_trees; i++) {
	struct tree *tree = trees[i];
	parse_tree(tree);
	init_tree_desc(t+i, tree->buffer, tree->size);
	}
	if (unpack_trees(nr_trees, t, &opts))
	return 128;

	if (opts.debug_unpack \|\| opts.dry_run)
	return 0; /* do not write the index out */

	/*
	* When reading only one tree (either the most basic form,
	* "-m ent" or "--reset ent" form), we can obtain a fully
	* valid cache-tree because the index must match exactly
	* what came from the tree.
	*/
	if (nr_trees == 1 && !opts.prefix)
	prime_cache_tree(&the_index, trees[0]);

	if (write_locked_index(&the_index, &lock_file, COMMIT_LOCK))
	die("unable to write new index file");
	return 0;
	}