1 files changed, 408 insertions, 160 deletions

diff --git a/builtin/cat-file.c b/builtin/cat-file.c
index 07bd984084..618103fdee 100644
--- a/builtin/cat-file.c
+++ b/builtin/cat-file.c
@@ -4,116 +4,71 @@
  * Copyright (C) Linus Torvalds, 2005
  */
 #include "cache.h"
-#include "exec_cmd.h"
-#include "tag.h"
-#include "tree.h"
 #include "builtin.h"
 #include "parse-options.h"
-#include "diff.h"
 #include "userdiff.h"
+#include "streaming.h"
+#include "tree-walk.h"
+#include "sha1-array.h"
+
+struct batch_options {
+	int enabled;
+	int follow_symlinks;
+	int print_contents;
+	int buffer_output;
+	int all_objects;
+	const char *format;
+};
 
-#define BATCH 1
-#define BATCH_CHECK 2
-
-static void pprint_tag(const unsigned char *sha1, const char *buf, unsigned long size)
-{
-	/* the parser in tag.c is useless here. */
-	const char *endp = buf + size;
-	const char *cp = buf;
-
-	while (cp < endp) {
-		char c = *cp++;
-		if (c != '\n')
-			continue;
-		if (7 <= endp - cp && !memcmp("tagger ", cp, 7)) {
-			const char *tagger = cp;
-
-			/* Found the tagger line.  Copy out the contents
-			 * of the buffer so far.
-			 */
-			write_or_die(1, buf, cp - buf);
-
-			/*
-			 * Do something intelligent, like pretty-printing
-			 * the date.
-			 */
-			while (cp < endp) {
-				if (*cp++ == '\n') {
-					/* tagger to cp is a line
-					 * that has ident and time.
-					 */
-					const char *sp = tagger;
-					char *ep;
-					unsigned long date;
-					long tz;
-					while (sp < cp && *sp != '>')
-						sp++;
-					if (sp == cp) {
-						/* give up */
-						write_or_die(1, tagger,
-							     cp - tagger);
-						break;
-					}
-					while (sp < cp &&
-					       !('0' <= *sp && *sp <= '9'))
-						sp++;
-					write_or_die(1, tagger, sp - tagger);
-					date = strtoul(sp, &ep, 10);
-					tz = strtol(ep, NULL, 10);
-					sp = show_date(date, tz, 0);
-					write_or_die(1, sp, strlen(sp));
-					xwrite(1, "\n", 1);
-					break;
-				}
-			}
-			break;
-		}
-		if (cp < endp && *cp == '\n')
-			/* end of header */
-			break;
-	}
-	/* At this point, we have copied out the header up to the end of
-	 * the tagger line and cp points at one past \n.  It could be the
-	 * next header line after the tagger line, or it could be another
-	 * \n that marks the end of the headers.  We need to copy out the
-	 * remainder as is.
-	 */
-	if (cp < endp)
-		write_or_die(1, cp, endp - cp);
-}
-
-static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
+static int cat_one_file(int opt, const char *exp_type, const char *obj_name,
+			int unknown_type)
 {
 	unsigned char sha1[20];
 	enum object_type type;
 	char *buf;
 	unsigned long size;
 	struct object_context obj_context;
+	struct object_info oi = {NULL};
+	struct strbuf sb = STRBUF_INIT;
+	unsigned flags = LOOKUP_REPLACE_OBJECT;
 
-	if (get_sha1_with_context(obj_name, sha1, &obj_context))
+	if (unknown_type)
+		flags |= LOOKUP_UNKNOWN_OBJECT;
+
+	if (get_sha1_with_context(obj_name, 0, sha1, &obj_context))
 		die("Not a valid object name %s", obj_name);
 
 	buf = NULL;
 	switch (opt) {
 	case 't':
-		type = sha1_object_info(sha1, NULL);
-		if (type > 0) {
-			printf("%s\n", typename(type));
+		oi.typename = &sb;
+		if (sha1_object_info_extended(sha1, &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':
-		type = sha1_object_info(sha1, &size);
-		if (type > 0) {
-			printf("%lu\n", size);
-			return 0;
-		}
-		break;
+		oi.sizep = &size;
+		if (sha1_object_info_extended(sha1, &oi, flags) < 0)
+			die("git cat-file: could not get object info");
+		printf("%lu\n", size);
+		return 0;
 
 	case 'e':
 		return !has_sha1_file(sha1);
 
+	case 'c':
+		if (!obj_context.path[0])
+			die("git cat-file --textconv %s: <object> must be <sha1:path>",
+			    obj_name);
+
+		if (textconv_object(obj_context.path, obj_context.mode, sha1, 1, &buf, &size))
+			break;
+
 	case 'p':
 		type = sha1_object_info(sha1, NULL);
 		if (type < 0)
@@ -127,28 +82,37 @@ static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
 			return cmd_ls_tree(2, ls_args, NULL);
 		}
 
+		if (type == OBJ_BLOB)
+			return stream_blob_to_fd(1, sha1, NULL, 0);
 		buf = read_sha1_file(sha1, &type, &size);
 		if (!buf)
 			die("Cannot read object %s", obj_name);
-		if (type == OBJ_TAG) {
-			pprint_tag(sha1, buf, size);
-			return 0;
-		}
 
 		/* otherwise just spit out the data */
 		break;
 
-	case 'c':
-		if (!obj_context.path[0])
-			die("git cat-file --textconv %s: <object> must be <sha1:path>",
-			    obj_name);
-
-		if (!textconv_object(obj_context.path, obj_context.mode, sha1, &buf, &size))
-			die("git cat-file --textconv: unable to run textconv on %s",
-			    obj_name);
-		break;
-
 	case 0:
+		if (type_from_string(exp_type) == OBJ_BLOB) {
+			unsigned char blob_sha1[20];
+			if (sha1_object_info(sha1, NULL) == OBJ_TAG) {
+				char *buffer = read_sha1_file(sha1, &type, &size);
+				const char *target;
+				if (!skip_prefix(buffer, "object ", &target) ||
+				    get_sha1_hex(target, blob_sha1))
+					die("%s not a valid tag", sha1_to_hex(sha1));
+				free(buffer);
+			} else
+				hashcpy(blob_sha1, sha1);
+
+			if (sha1_object_info(blob_sha1, NULL) == OBJ_BLOB)
+				return stream_blob_to_fd(1, blob_sha1, NULL, 0);
+			/*
+			 * 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(sha1, exp_type, &size, NULL);
 		break;
 
@@ -163,109 +127,384 @@ static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
 	return 0;
 }
 
-static int batch_one_object(const char *obj_name, int print_contents)
-{
+struct expand_data {
 	unsigned char sha1[20];
-	enum object_type type = 0;
+	enum object_type type;
 	unsigned long size;
-	void *contents = contents;
+	unsigned long disk_size;
+	const char *rest;
+	unsigned char delta_base_sha1[20];
 
-	if (!obj_name)
-	   return 1;
+	/*
+	 * 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;
 
-	if (get_sha1(obj_name, sha1)) {
-		printf("%s missing\n", obj_name);
-		fflush(stdout);
+	/*
+	 * 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 sha1_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 sha1_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, sha1_to_hex(data->sha1));
+	} else if (is_atom("objecttype", atom, len)) {
+		if (data->mark_query)
+			data->info.typep = &data->type;
+		else
+			strbuf_addstr(sb, typename(data->type));
+	} else if (is_atom("objectsize", atom, len)) {
+		if (data->mark_query)
+			data->info.sizep = &data->size;
+		else
+			strbuf_addf(sb, "%lu", 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, "%lu", 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_sha1;
+		else
+			strbuf_addstr(sb, sha1_to_hex(data->delta_base_sha1));
+	} 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 unsigned char *sha1 = data->sha1;
+
+	assert(data->info.typep);
+
+	if (data->type == OBJ_BLOB) {
+		if (opt->buffer_output)
+			fflush(stdout);
+		if (stream_blob_to_fd(1, sha1, NULL, 0) < 0)
+			die("unable to stream %s to stdout", sha1_to_hex(sha1));
 	}
+	else {
+		enum object_type type;
+		unsigned long size;
+		void *contents;
 
-	if (print_contents == BATCH)
 		contents = read_sha1_file(sha1, &type, &size);
-	else
-		type = sha1_object_info(sha1, &size);
+		if (!contents)
+			die("object %s disappeared", sha1_to_hex(sha1));
+		if (type != data->type)
+			die("object %s changed type!?", sha1_to_hex(sha1));
+		if (data->info.sizep && size != data->size)
+			die("object %s changed size!?", sha1_to_hex(sha1));
+
+		batch_write(opt, contents, size);
+		free(contents);
+	}
+}
+
+static void batch_object_write(const char *obj_name, struct batch_options *opt,
+			       struct expand_data *data)
+{
+	struct strbuf buf = STRBUF_INIT;
 
-	if (type <= 0) {
-		printf("%s missing\n", obj_name);
+	if (!data->skip_object_info &&
+	    sha1_object_info_extended(data->sha1, &data->info, LOOKUP_REPLACE_OBJECT) < 0) {
+		printf("%s missing\n", obj_name ? obj_name : sha1_to_hex(data->sha1));
 		fflush(stdout);
-		if (print_contents == BATCH)
-			free(contents);
-		return 0;
+		return;
 	}
 
-	printf("%s %s %lu\n", sha1_to_hex(sha1), typename(type), size);
-	fflush(stdout);
+	strbuf_expand(&buf, opt->format, expand_format, data);
+	strbuf_addch(&buf, '\n');
+	batch_write(opt, buf.buf, buf.len);
+	strbuf_release(&buf);
 
-	if (print_contents == BATCH) {
-		write_or_die(1, contents, size);
-		printf("\n");
+	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 batch_options *opt,
+			     struct expand_data *data)
+{
+	struct object_context ctx;
+	int flags = opt->follow_symlinks ? GET_SHA1_FOLLOW_SYMLINKS : 0;
+	enum follow_symlinks_result result;
+
+	result = get_sha1_with_context(obj_name, flags, data->sha1, &ctx);
+	if (result != FOUND) {
+		switch (result) {
+		case MISSING_OBJECT:
+			printf("%s missing\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:
+			die("BUG: unknown get_sha1_with_context result %d\n",
+			       result);
+			break;
+		}
 		fflush(stdout);
-		free(contents);
+		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, opt, data);
+}
+
+struct object_cb_data {
+	struct batch_options *opt;
+	struct expand_data *expand;
+};
+
+static void batch_object_cb(const unsigned char sha1[20], void *vdata)
+{
+	struct object_cb_data *data = vdata;
+	hashcpy(data->expand->sha1, sha1);
+	batch_object_write(NULL, data->opt, data->expand);
+}
+
+static int batch_loose_object(const unsigned char *sha1,
+			      const char *path,
+			      void *data)
+{
+	sha1_array_append(data, sha1);
 	return 0;
 }
 
-static int batch_objects(int print_contents)
+static int batch_packed_object(const unsigned char *sha1,
+			       struct packed_git *pack,
+			       uint32_t pos,
+			       void *data)
+{
+	sha1_array_append(data, sha1);
+	return 0;
+}
+
+static int batch_objects(struct batch_options *opt)
 {
 	struct strbuf buf = STRBUF_INIT;
+	struct expand_data data;
+	int save_warning;
+	int retval = 0;
+
+	if (!opt->format)
+		opt->format = "%(objectname) %(objecttype) %(objectsize)";
 
-	while (strbuf_getline(&buf, stdin, '\n') != EOF) {
-		int error = batch_one_object(buf.buf, print_contents);
-		if (error)
-			return error;
+	/*
+	 * Expand once with our special mark_query flag, which will prime the
+	 * object_info to be handed to sha1_object_info_extended for each
+	 * object.
+	 */
+	memset(&data, 0, sizeof(data));
+	data.mark_query = 1;
+	strbuf_expand(&buf, opt->format, expand_format, &data);
+	data.mark_query = 0;
+
+	if (opt->all_objects) {
+		struct object_info empty;
+		memset(&empty, 0, sizeof(empty));
+		if (!memcmp(&data.info, &empty, sizeof(empty)))
+			data.skip_object_info = 1;
 	}
 
-	return 0;
+	/*
+	 * 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 sha1_array sa = SHA1_ARRAY_INIT;
+		struct object_cb_data cb;
+
+		for_each_loose_object(batch_loose_object, &sa, 0);
+		for_each_packed_object(batch_packed_object, &sa, 0);
+
+		cb.opt = opt;
+		cb.expand = &data;
+		sha1_array_for_each_unique(&sa, batch_object_cb, &cb);
+
+		sha1_array_clear(&sa);
+		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(&buf, 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(buf.buf, " \t");
+			if (p) {
+				while (*p && strchr(" \t", *p))
+					*p++ = '\0';
+			}
+			data.rest = p;
+		}
+
+		batch_one_object(buf.buf, opt, &data);
+	}
+
+	strbuf_release(&buf);
+	warn_on_object_refname_ambiguity = save_warning;
+	return retval;
 }
 
 static const char * const cat_file_usage[] = {
-	"git cat-file (-t|-s|-e|-p|<type>|--textconv) <object>",
-	"git cat-file (--batch|--batch-check) < <list_of_objects>",
+	N_("git cat-file (-t [--allow-unknown-type]|-s [--allow-unknown-type]|-e|-p|<type>|--textconv) <object>"),
+	N_("git cat-file (--batch | --batch-check) [--follow-symlinks]"),
 	NULL
 };
 
 static int git_cat_file_config(const char *var, const char *value, void *cb)
 {
-	switch (userdiff_config(var, value)) {
-	case 0:
-		break;
-	case -1:
+	if (userdiff_config(var, value) < 0)
 		return -1;
-	default:
-		return 0;
-	}
 
 	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;
+
+	if (bo->enabled) {
+		return 1;
+	}
+
+	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, batch = 0;
+	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("<type> can be one of: blob, tree, commit, tag"),
-		OPT_SET_INT('t', NULL, &opt, "show object type", 't'),
-		OPT_SET_INT('s', NULL, &opt, "show object size", 's'),
-		OPT_SET_INT('e', NULL, &opt,
-			    "exit with zero when there's no error", 'e'),
-		OPT_SET_INT('p', NULL, &opt, "pretty-print object's content", 'p'),
-		OPT_SET_INT(0, "textconv", &opt,
-			    "for blob objects, run textconv on object's content", 'c'),
-		OPT_SET_INT(0, "batch", &batch,
-			    "show info and content of objects fed from the standard input",
-			    BATCH),
-		OPT_SET_INT(0, "batch-check", &batch,
-			    "show info about objects fed from the standard input",
-			    BATCH_CHECK),
+		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_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, batch_option_callback },
+		{ OPTION_CALLBACK, 0, "batch-check", &batch, "format",
+			N_("show info about objects fed from the standard input"),
+			PARSE_OPT_OPTARG, 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_END()
 	};
 
 	git_config(git_cat_file_config, NULL);
 
-	if (argc != 3 && argc != 2)
-		usage_with_options(cat_file_usage, options);
-
+	batch.buffer_output = -1;
 	argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
 
 	if (opt) {
@@ -274,19 +513,28 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
 		else
 			usage_with_options(cat_file_usage, options);
 	}
-	if (!opt && !batch) {
+	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 && (opt || argc)) {
+	if (batch.enabled && (opt || argc)) {
 		usage_with_options(cat_file_usage, options);
 	}
 
-	if (batch)
-		return batch_objects(batch);
+	if ((batch.follow_symlinks || batch.all_objects) && !batch.enabled) {
+		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);
 
-	return cat_one_file(opt, exp_type, obj_name);
+	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);
 }