Re: [PATCH v6 2/4] cat-file: teach cat-file a '--literally' option

[karthik nayak <karthik.188@gmail.com>]

On 04/03/2015 12:38 AM, Junio C Hamano wrote:
> Karthik Nayak <karthik.188@gmail.com> writes:
>
>> Currently 'git cat-file' throws an error while trying to
>> print the type or size of a broken/corrupt object which is
>> created using 'git hash-object --literally'. This is
>> because these objects are usually of unknown types.
>>
>> Teach git cat-file a '--literally' option where it prints
>> the type or size of a broken/corrupt object without throwing
>> an error.
>>
>> Modify '-t' and '-s' options to call sha1_object_info_extended()
>> directly to support the '--literally' option.
>>
>> Helped-by: Junio C Hamano <gitster@pobox.com>
>> Helped-by: Eric Sunshine <sunshine@sunshineco
>
> s/$/.com/ perhaps?
Definitely!
>
>> Signed-off-by: Karthik Nayak <karthik.188@gmail.com>
>> ---
>>   builtin/cat-file.c | 38 +++++++++++++++++++++++++++++---------
>>   1 file changed, 29 insertions(+), 9 deletions(-)
>>
>> diff --git a/builtin/cat-file.c b/builtin/cat-file.c
>> index df99df4..91ceae0 100644
>> --- a/builtin/cat-file.c
>> +++ b/builtin/cat-file.c
>> @@ -9,13 +9,20 @@
>>   #include "userdiff.h"
>>   #include "streaming.h"
>>
>> -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 literally)
>>   {
>>   	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 (literally)
>> +		flags |= LOOKUP_LITERALLY;
>>
>>   	if (get_sha1_with_context(obj_name, 0, sha1, &obj_context))
>>   		die("Not a valid object name %s", obj_name);
>> @@ -23,16 +30,24 @@ static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
>>   	buf = NULL;
>>   	switch (opt) {
>>   	case 't':
>> -		type = sha1_object_info(sha1, NULL);
>> -		if (type > 0) {
>> -			printf("%s\n", typename(type));
>> +		oi.typep = &type;
>> +		oi.typename = &sb;
>> +		if (sha1_object_info_extended(sha1, &oi, flags) < 0)
>> +			die("git cat-file: could not get object info");
>> +		if (type >= 0 && sb.len) {
>> +			printf("%s\n", sb.buf);
>> +			strbuf_release(&sb);
>>   			return 0;
>>   		}
>>   		break;
>>
>>   	case 's':
>> -		type = sha1_object_info(sha1, &size);
>> -		if (type > 0) {
>> +		oi.typep = &type;
>> +		oi.typename = &sb;
>> +		oi.sizep = &size;
>> +		if (sha1_object_info_extended(sha1, &oi, flags) < 0)
>> +			die("git cat-file: could not get object info");
>> +		if (type >= 0 && sb.len) {
>>   			printf("%lu\n", size);
>>   			return 0;
>>   		}
>> @@ -323,7 +338,7 @@ static int batch_objects(struct batch_options *opt)
>>   }
>>
>>   static const char * const cat_file_usage[] = {
>> -	N_("git cat-file (-t | -s | -e | -p | <type> | --textconv) <object>"),
>> +	N_("git cat-file (-t [--literally]|-s [--literally]|-e|-p|<type>|--textconv) <object>"),
>>   	N_("git cat-file (--batch | --batch-check) < <list-of-objects>"),
>>   	NULL
>>   };
>> @@ -359,6 +374,7 @@ 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 literally = 0;
>>
>>   	const struct option options[] = {
>>   		OPT_GROUP(N_("<type> can be one of: blob, tree, commit, tag")),
>> @@ -369,6 +385,8 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
>>   		OPT_SET_INT('p', NULL, &opt, N_("pretty-print object's content"), 'p'),
>>   		OPT_SET_INT(0, "textconv", &opt,
>>   			    N_("for blob objects, run textconv on object's content"), 'c'),
>> +		OPT_BOOL( 0, "literally", &literally,
>> +			  N_("get information about corrupt objects for debugging Git")),
>>   		{ OPTION_CALLBACK, 0, "batch", &batch, "format",
>>   			N_("show info and content of objects fed from the standard input"),
>>   			PARSE_OPT_OPTARG, batch_option_callback },
>> @@ -380,7 +398,7 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
>>
>>   	git_config(git_cat_file_config, NULL);
>>
>> -	if (argc != 3 && argc != 2)
>> +	if (argc < 2 || argc > 4)
>>   		usage_with_options(cat_file_usage, options);
>>
>>   	argc = parse_options(argc, argv, prefix, options, cat_file_usage, 0);
>> @@ -405,5 +423,7 @@ int cmd_cat_file(int argc, const char **argv, const char *prefix)
>>   	if (batch.enabled)
>>   		return batch_objects(&batch);
>>
>> -	return cat_one_file(opt, exp_type, obj_name);
>> +	if (literally && opt != 't' && opt != 's')
>> +		die("git cat-file --literally: use with -s or -t");
>> +	return cat_one_file(opt, exp_type, obj_name, literally);
>>   }