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-rw-r--r--builtin/cat-file.c717
1 files changed, 717 insertions, 0 deletions
diff --git a/builtin/cat-file.c b/builtin/cat-file.c
new file mode 100644
index 000000000000..995d47c85aad
--- /dev/null
+++ b/builtin/cat-file.c
@@ -0,0 +1,717 @@
+/*
+ * GIT - The information manager from hell
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ */
+#define USE_THE_INDEX_COMPATIBILITY_MACROS
+#include "cache.h"
+#include "config.h"
+#include "builtin.h"
+#include "diff.h"
+#include "parse-options.h"
+#include "userdiff.h"
+#include "streaming.h"
+#include "tree-walk.h"
+#include "sha1-array.h"
+#include "packfile.h"
+#include "object-store.h"
+
+struct batch_options {
+	int enabled;
+	int follow_symlinks;
+	int print_contents;
+	int buffer_output;
+	int all_objects;
+	int unordered;
+	int cmdmode; /* may be 'w' or 'c' for --filters or --textconv */
+	const char *format;
+};
+
+static const char *force_path;
+
+static int filter_object(const char *path, unsigned mode,
+			 const struct object_id *oid,
+			 char **buf, unsigned long *size)
+{
+	enum object_type type;
+
+	*buf = read_object_file(oid, &type, size);
+	if (!*buf)
+		return error(_("cannot read object %s '%s'"),
+			     oid_to_hex(oid), path);
+	if ((type == OBJ_BLOB) && S_ISREG(mode)) {
+		struct strbuf strbuf = STRBUF_INIT;
+		if (convert_to_working_tree(&the_index, path, *buf, *size, &strbuf)) {
+			free(*buf);
+			*size = strbuf.len;
+			*buf = strbuf_detach(&strbuf, NULL);
+		}
+	}
+
+	return 0;
+}
+
+static int stream_blob(const struct object_id *oid)
+{
+	if (stream_blob_to_fd(1, oid, NULL, 0))
+		die("unable to stream %s to stdout", oid_to_hex(oid));
+	return 0;
+}
+
+static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
+			int unknown_type)
+{
+	struct object_id oid;
+	enum object_type type;
+	char *buf;
+	unsigned long size;
+	struct object_context obj_context;
+	struct object_info oi = OBJECT_INFO_INIT;
+	struct strbuf sb = STRBUF_INIT;
+	unsigned flags = OBJECT_INFO_LOOKUP_REPLACE;
+	const char *path = force_path;
+
+	if (unknown_type)
+		flags |= OBJECT_INFO_ALLOW_UNKNOWN_TYPE;
+
+	if (get_oid_with_context(the_repository, obj_name,
+				 GET_OID_RECORD_PATH,
+				 &oid, &obj_context))
+		die("Not a valid object name %s", obj_name);
+
+	if (!path)
+		path = obj_context.path;
+	if (obj_context.mode == S_IFINVALID)
+		obj_context.mode = 0100644;
+
+	buf = NULL;
+	switch (opt) {
+	case 't':
+		oi.type_name = &sb;
+		if (oid_object_info_extended(the_repository, &oid, &oi, flags) < 0)
+			die("git cat-file: could not get object info");
+		if (sb.len) {
+			printf("%s\n", sb.buf);
+			strbuf_release(&sb);
+			return 0;
+		}
+		break;
+
+	case 's':
+		oi.sizep = &size;
+		if (oid_object_info_extended(the_repository, &oid, &oi, flags) < 0)
+			die("git cat-file: could not get object info");
+		printf("%"PRIuMAX"\n", (uintmax_t)size);
+		return 0;
+
+	case 'e':
+		return !has_object_file(&oid);
+
+	case 'w':
+		if (!path)
+			die("git cat-file --filters %s: <object> must be "
+			    "<sha1:path>", obj_name);
+
+		if (filter_object(path, obj_context.mode,
+				  &oid, &buf, &size))
+			return -1;
+		break;
+
+	case 'c':
+		if (!path)
+			die("git cat-file --textconv %s: <object> must be <sha1:path>",
+			    obj_name);
+
+		if (textconv_object(the_repository, path, obj_context.mode,
+				    &oid, 1, &buf, &size))
+			break;
+		/* else fallthrough */
+
+	case 'p':
+		type = oid_object_info(the_repository, &oid, NULL);
+		if (type < 0)
+			die("Not a valid object name %s", obj_name);
+
+		/* custom pretty-print here */
+		if (type == OBJ_TREE) {
+			const char *ls_args[3] = { NULL };
+			ls_args[0] =  "ls-tree";
+			ls_args[1] =  obj_name;
+			return cmd_ls_tree(2, ls_args, NULL);
+		}
+
+		if (type == OBJ_BLOB)
+			return stream_blob(&oid);
+		buf = read_object_file(&oid, &type, &size);
+		if (!buf)
+			die("Cannot read object %s", obj_name);
+
+		/* otherwise just spit out the data */
+		break;
+
+	case 0:
+		if (type_from_string(exp_type) == OBJ_BLOB) {
+			struct object_id blob_oid;
+			if (oid_object_info(the_repository, &oid, NULL) == OBJ_TAG) {
+				char *buffer = read_object_file(&oid, &type,
+								&size);
+				const char *target;
+				if (!skip_prefix(buffer, "object ", &target) ||
+				    get_oid_hex(target, &blob_oid))
+					die("%s not a valid tag", oid_to_hex(&oid));
+				free(buffer);
+			} else
+				oidcpy(&blob_oid, &oid);
+
+			if (oid_object_info(the_repository, &blob_oid, NULL) == OBJ_BLOB)
+				return stream_blob(&blob_oid);
+			/*
+			 * we attempted to dereference a tag to a blob
+			 * and failed; there may be new dereference
+			 * mechanisms this code is not aware of.
+			 * fall-back to the usual case.
+			 */
+		}
+		buf = read_object_with_reference(the_repository,
+						 &oid, exp_type, &size, NULL);
+		break;
+
+	default:
+		die("git cat-file: unknown option: %s", exp_type);
+	}
+
+	if (!buf)
+		die("git cat-file %s: bad file", obj_name);
+
+	write_or_die(1, buf, size);
+	free(buf);
+	free(obj_context.path);
+	return 0;
+}
+
+struct expand_data {
+	struct object_id oid;
+	enum object_type type;
+	unsigned long size;
+	off_t disk_size;
+	const char *rest;
+	struct object_id delta_base_oid;
+
+	/*
+	 * If mark_query is true, we do not expand anything, but rather
+	 * just mark the object_info with items we wish to query.
+	 */
+	int mark_query;
+
+	/*
+	 * Whether to split the input on whitespace before feeding it to
+	 * get_sha1; this is decided during the mark_query phase based on
+	 * whether we have a %(rest) token in our format.
+	 */
+	int split_on_whitespace;
+
+	/*
+	 * After a mark_query run, this object_info is set up to be
+	 * passed to oid_object_info_extended. It will point to the data
+	 * elements above, so you can retrieve the response from there.
+	 */
+	struct object_info info;
+
+	/*
+	 * This flag will be true if the requested batch format and options
+	 * don't require us to call oid_object_info, which can then be
+	 * optimized out.
+	 */
+	unsigned skip_object_info : 1;
+};
+
+static int is_atom(const char *atom, const char *s, int slen)
+{
+	int alen = strlen(atom);
+	return alen == slen && !memcmp(atom, s, alen);
+}
+
+static void expand_atom(struct strbuf *sb, const char *atom, int len,
+			void *vdata)
+{
+	struct expand_data *data = vdata;
+
+	if (is_atom("objectname", atom, len)) {
+		if (!data->mark_query)
+			strbuf_addstr(sb, oid_to_hex(&data->oid));
+	} else if (is_atom("objecttype", atom, len)) {
+		if (data->mark_query)
+			data->info.typep = &data->type;
+		else
+			strbuf_addstr(sb, type_name(data->type));
+	} else if (is_atom("objectsize", atom, len)) {
+		if (data->mark_query)
+			data->info.sizep = &data->size;
+		else
+			strbuf_addf(sb, "%"PRIuMAX , (uintmax_t)data->size);
+	} else if (is_atom("objectsize:disk", atom, len)) {
+		if (data->mark_query)
+			data->info.disk_sizep = &data->disk_size;
+		else
+			strbuf_addf(sb, "%"PRIuMAX, (uintmax_t)data->disk_size);
+	} else if (is_atom("rest", atom, len)) {
+		if (data->mark_query)
+			data->split_on_whitespace = 1;
+		else if (data->rest)
+			strbuf_addstr(sb, data->rest);
+	} else if (is_atom("deltabase", atom, len)) {
+		if (data->mark_query)
+			data->info.delta_base_sha1 = data->delta_base_oid.hash;
+		else
+			strbuf_addstr(sb,
+				      oid_to_hex(&data->delta_base_oid));
+	} else
+		die("unknown format element: %.*s", len, atom);
+}
+
+static size_t expand_format(struct strbuf *sb, const char *start, void *data)
+{
+	const char *end;
+
+	if (*start != '(')
+		return 0;
+	end = strchr(start + 1, ')');
+	if (!end)
+		die("format element '%s' does not end in ')'", start);
+
+	expand_atom(sb, start + 1, end - start - 1, data);
+
+	return end - start + 1;
+}
+
+static void batch_write(struct batch_options *opt, const void *data, int len)
+{
+	if (opt->buffer_output) {
+		if (fwrite(data, 1, len, stdout) != len)
+			die_errno("unable to write to stdout");
+	} else
+		write_or_die(1, data, len);
+}
+
+static void print_object_or_die(struct batch_options *opt, struct expand_data *data)
+{
+	const struct object_id *oid = &data->oid;
+
+	assert(data->info.typep);
+
+	if (data->type == OBJ_BLOB) {
+		if (opt->buffer_output)
+			fflush(stdout);
+		if (opt->cmdmode) {
+			char *contents;
+			unsigned long size;
+
+			if (!data->rest)
+				die("missing path for '%s'", oid_to_hex(oid));
+
+			if (opt->cmdmode == 'w') {
+				if (filter_object(data->rest, 0100644, oid,
+						  &contents, &size))
+					die("could not convert '%s' %s",
+					    oid_to_hex(oid), data->rest);
+			} else if (opt->cmdmode == 'c') {
+				enum object_type type;
+				if (!textconv_object(the_repository,
+						     data->rest, 0100644, oid,
+						     1, &contents, &size))
+					contents = read_object_file(oid,
+								    &type,
+								    &size);
+				if (!contents)
+					die("could not convert '%s' %s",
+					    oid_to_hex(oid), data->rest);
+			} else
+				BUG("invalid cmdmode: %c", opt->cmdmode);
+			batch_write(opt, contents, size);
+			free(contents);
+		} else {
+			stream_blob(oid);
+		}
+	}
+	else {
+		enum object_type type;
+		unsigned long size;
+		void *contents;
+
+		contents = read_object_file(oid, &type, &size);
+		if (!contents)
+			die("object %s disappeared", oid_to_hex(oid));
+		if (type != data->type)
+			die("object %s changed type!?", oid_to_hex(oid));
+		if (data->info.sizep && size != data->size)
+			die("object %s changed size!?", oid_to_hex(oid));
+
+		batch_write(opt, contents, size);
+		free(contents);
+	}
+}
+
+static void batch_object_write(const char *obj_name,
+			       struct strbuf *scratch,
+			       struct batch_options *opt,
+			       struct expand_data *data)
+{
+	if (!data->skip_object_info &&
+	    oid_object_info_extended(the_repository, &data->oid, &data->info,
+				     OBJECT_INFO_LOOKUP_REPLACE) < 0) {
+		printf("%s missing\n",
+		       obj_name ? obj_name : oid_to_hex(&data->oid));
+		fflush(stdout);
+		return;
+	}
+
+	strbuf_reset(scratch);
+	strbuf_expand(scratch, opt->format, expand_format, data);
+	strbuf_addch(scratch, '\n');
+	batch_write(opt, scratch->buf, scratch->len);
+
+	if (opt->print_contents) {
+		print_object_or_die(opt, data);
+		batch_write(opt, "\n", 1);
+	}
+}
+
+static void batch_one_object(const char *obj_name,
+			     struct strbuf *scratch,
+			     struct batch_options *opt,
+			     struct expand_data *data)
+{
+	struct object_context ctx;
+	int flags = opt->follow_symlinks ? GET_OID_FOLLOW_SYMLINKS : 0;
+	enum get_oid_result result;
+
+	result = get_oid_with_context(the_repository, obj_name,
+				      flags, &data->oid, &ctx);
+	if (result != FOUND) {
+		switch (result) {
+		case MISSING_OBJECT:
+			printf("%s missing\n", obj_name);
+			break;
+		case SHORT_NAME_AMBIGUOUS:
+			printf("%s ambiguous\n", obj_name);
+			break;
+		case DANGLING_SYMLINK:
+			printf("dangling %"PRIuMAX"\n%s\n",
+			       (uintmax_t)strlen(obj_name), obj_name);
+			break;
+		case SYMLINK_LOOP:
+			printf("loop %"PRIuMAX"\n%s\n",
+			       (uintmax_t)strlen(obj_name), obj_name);
+			break;
+		case NOT_DIR:
+			printf("notdir %"PRIuMAX"\n%s\n",
+			       (uintmax_t)strlen(obj_name), obj_name);
+			break;
+		default:
+			BUG("unknown get_sha1_with_context result %d\n",
+			       result);
+			break;
+		}
+		fflush(stdout);
+		return;
+	}
+
+	if (ctx.mode == 0) {
+		printf("symlink %"PRIuMAX"\n%s\n",
+		       (uintmax_t)ctx.symlink_path.len,
+		       ctx.symlink_path.buf);
+		fflush(stdout);
+		return;
+	}
+
+	batch_object_write(obj_name, scratch, opt, data);
+}
+
+struct object_cb_data {
+	struct batch_options *opt;
+	struct expand_data *expand;
+	struct oidset *seen;
+	struct strbuf *scratch;
+};
+
+static int batch_object_cb(const struct object_id *oid, void *vdata)
+{
+	struct object_cb_data *data = vdata;
+	oidcpy(&data->expand->oid, oid);
+	batch_object_write(NULL, data->scratch, data->opt, data->expand);
+	return 0;
+}
+
+static int collect_loose_object(const struct object_id *oid,
+				const char *path,
+				void *data)
+{
+	oid_array_append(data, oid);
+	return 0;
+}
+
+static int collect_packed_object(const struct object_id *oid,
+				 struct packed_git *pack,
+				 uint32_t pos,
+				 void *data)
+{
+	oid_array_append(data, oid);
+	return 0;
+}
+
+static int batch_unordered_object(const struct object_id *oid, void *vdata)
+{
+	struct object_cb_data *data = vdata;
+
+	if (oidset_insert(data->seen, oid))
+		return 0;
+
+	return batch_object_cb(oid, data);
+}
+
+static int batch_unordered_loose(const struct object_id *oid,
+				 const char *path,
+				 void *data)
+{
+	return batch_unordered_object(oid, data);
+}
+
+static int batch_unordered_packed(const struct object_id *oid,
+				  struct packed_git *pack,
+				  uint32_t pos,
+				  void *data)
+{
+	return batch_unordered_object(oid, data);
+}
+
+static int batch_objects(struct batch_options *opt)
+{
+	struct strbuf input = STRBUF_INIT;
+	struct strbuf output = STRBUF_INIT;
+	struct expand_data data;
+	int save_warning;
+	int retval = 0;
+
+	if (!opt->format)
+		opt->format = "%(objectname) %(objecttype) %(objectsize)";
+
+	/*
+	 * Expand once with our special mark_query flag, which will prime the
+	 * object_info to be handed to oid_object_info_extended for each
+	 * object.
+	 */
+	memset(&data, 0, sizeof(data));
+	data.mark_query = 1;
+	strbuf_expand(&output, opt->format, expand_format, &data);
+	data.mark_query = 0;
+	strbuf_release(&output);
+	if (opt->cmdmode)
+		data.split_on_whitespace = 1;
+
+	if (opt->all_objects) {
+		struct object_info empty = OBJECT_INFO_INIT;
+		if (!memcmp(&data.info, &empty, sizeof(empty)))
+			data.skip_object_info = 1;
+	}
+
+	/*
+	 * If we are printing out the object, then always fill in the type,
+	 * since we will want to decide whether or not to stream.
+	 */
+	if (opt->print_contents)
+		data.info.typep = &data.type;
+
+	if (opt->all_objects) {
+		struct object_cb_data cb;
+
+		if (repository_format_partial_clone)
+			warning("This repository has extensions.partialClone set. Some objects may not be loaded.");
+
+		cb.opt = opt;
+		cb.expand = &data;
+		cb.scratch = &output;
+
+		if (opt->unordered) {
+			struct oidset seen = OIDSET_INIT;
+
+			cb.seen = &seen;
+
+			for_each_loose_object(batch_unordered_loose, &cb, 0);
+			for_each_packed_object(batch_unordered_packed, &cb,
+					       FOR_EACH_OBJECT_PACK_ORDER);
+
+			oidset_clear(&seen);
+		} else {
+			struct oid_array sa = OID_ARRAY_INIT;
+
+			for_each_loose_object(collect_loose_object, &sa, 0);
+			for_each_packed_object(collect_packed_object, &sa, 0);
+
+			oid_array_for_each_unique(&sa, batch_object_cb, &cb);
+
+			oid_array_clear(&sa);
+		}
+
+		strbuf_release(&output);
+		return 0;
+	}
+
+	/*
+	 * We are going to call get_sha1 on a potentially very large number of
+	 * objects. In most large cases, these will be actual object sha1s. The
+	 * cost to double-check that each one is not also a ref (just so we can
+	 * warn) ends up dwarfing the actual cost of the object lookups
+	 * themselves. We can work around it by just turning off the warning.
+	 */
+	save_warning = warn_on_object_refname_ambiguity;
+	warn_on_object_refname_ambiguity = 0;
+
+	while (strbuf_getline(&input, stdin) != EOF) {
+		if (data.split_on_whitespace) {
+			/*
+			 * Split at first whitespace, tying off the beginning
+			 * of the string and saving the remainder (or NULL) in
+			 * data.rest.
+			 */
+			char *p = strpbrk(input.buf, " \t");
+			if (p) {
+				while (*p && strchr(" \t", *p))
+					*p++ = '\0';
+			}
+			data.rest = p;
+		}
+
+		batch_one_object(input.buf, &output, opt, &data);
+	}
+
+	strbuf_release(&input);
+	strbuf_release(&output);
+	warn_on_object_refname_ambiguity = save_warning;
+	return retval;
+}
+
+static const char * const cat_file_usage[] = {
+	N_("git cat-file (-t [--allow-unknown-type] | -s [--allow-unknown-type] | -e | -p | <type> | --textconv | --filters) [--path=<path>] <object>"),
+	N_("git cat-file (--batch | --batch-check) [--follow-symlinks] [--textconv | --filters]"),
+	NULL
+};
+
+static int git_cat_file_config(const char *var, const char *value, void *cb)
+{
+	if (userdiff_config(var, value) < 0)
+		return -1;
+
+	return git_default_config(var, value, cb);
+}
+
+static int batch_option_callback(const struct option *opt,
+				 const char *arg,
+				 int unset)
+{
+	struct batch_options *bo = opt->value;
+
+	BUG_ON_OPT_NEG(unset);
+
+	if (bo->enabled) {
+		return error(_("only one batch option may be specified"));
+	}
+
+	bo->enabled = 1;
+	bo->print_contents = !strcmp(opt->long_name, "batch");
+	bo->format = arg;
+
+	return 0;
+}
+
+int cmd_cat_file(int argc, const char **argv, const char *prefix)
+{
+	int opt = 0;
+	const char *exp_type = NULL, *obj_name = NULL;
+	struct batch_options batch = {0};
+	int unknown_type = 0;
+
+	const struct option options[] = {
+		OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
+		OPT_CMDMODE('t', NULL, &opt, N_("show object type"), 't'),
+		OPT_CMDMODE('s', NULL, &opt, N_("show object size"), 's'),
+		OPT_CMDMODE('e', NULL, &opt,
+			    N_("exit with zero when there's no error"), 'e'),
+		OPT_CMDMODE('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
+		OPT_CMDMODE(0, "textconv", &opt,
+			    N_("for blob objects, run textconv on object's content"), 'c'),
+		OPT_CMDMODE(0, "filters", &opt,
+			    N_("for blob objects, run filters on object's content"), 'w'),
+		OPT_STRING(0, "path", &force_path, N_("blob"),
+			   N_("use a specific path for --textconv/--filters")),
+		OPT_BOOL(0, "allow-unknown-type", &unknown_type,
+			  N_("allow -s and -t to work with broken/corrupt objects")),
+		OPT_BOOL(0, "buffer", &batch.buffer_output, N_("buffer --batch output")),
+		{ OPTION_CALLBACK, 0, "batch", &batch, "format",
+			N_("show info and content of objects fed from the standard input"),
+			PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
+			batch_option_callback },
+		{ OPTION_CALLBACK, 0, "batch-check", &batch, "format",
+			N_("show info about objects fed from the standard input"),
+			PARSE_OPT_OPTARG | PARSE_OPT_NONEG,
+			batch_option_callback },
+		OPT_BOOL(0, "follow-symlinks", &batch.follow_symlinks,
+			 N_("follow in-tree symlinks (used with --batch or --batch-check)")),
+		OPT_BOOL(0, "batch-all-objects", &batch.all_objects,
+			 N_("show all objects with --batch or --batch-check")),
+		OPT_BOOL(0, "unordered", &batch.unordered,
+			 N_("do not order --batch-all-objects output")),
+		OPT_END()
+	};
+
+	git_config(git_cat_file_config, NULL);
+
+	batch.buffer_output = -1;
+	argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
+
+	if (opt) {
+		if (batch.enabled && (opt == 'c' || opt == 'w'))
+			batch.cmdmode = opt;
+		else if (argc == 1)
+			obj_name = argv[0];
+		else
+			usage_with_options(cat_file_usage, options);
+	}
+	if (!opt && !batch.enabled) {
+		if (argc == 2) {
+			exp_type = argv[0];
+			obj_name = argv[1];
+		} else
+			usage_with_options(cat_file_usage, options);
+	}
+	if (batch.enabled) {
+		if (batch.cmdmode != opt || argc)
+			usage_with_options(cat_file_usage, options);
+		if (batch.cmdmode && batch.all_objects)
+			die("--batch-all-objects cannot be combined with "
+			    "--textconv nor with --filters");
+	}
+
+	if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
+		usage_with_options(cat_file_usage, options);
+	}
+
+	if (force_path && opt != 'c' && opt != 'w') {
+		error("--path=<path> needs --textconv or --filters");
+		usage_with_options(cat_file_usage, options);
+	}
+
+	if (force_path && batch.enabled) {
+		error("--path=<path> incompatible with --batch");
+		usage_with_options(cat_file_usage, options);
+	}
+
+	if (batch.buffer_output < 0)
+		batch.buffer_output = batch.all_objects;
+
+	if (batch.enabled)
+		return batch_objects(&batch);
+
+	if (unknown_type && opt != 't' && opt != 's')
+		die("git cat-file --allow-unknown-type: use with -s or -t");
+	return cat_one_file(opt, exp_type, obj_name, unknown_type);
+}