git/list-objects-filter-options.h

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#ifndef LIST_OBJECTS_FILTER_OPTIONS_H
#define LIST_OBJECTS_FILTER_OPTIONS_H
#include "gettext.h"
#include "object.h"
#include "strbuf.h"
struct option;
/*
* The list of defined filters for list-objects.
*/
enum list_objects_filter_choice {
LOFC_DISABLED = 0,
LOFC_BLOB_NONE,
LOFC_BLOB_LIMIT,
LOFC_TREE_DEPTH,
LOFC_SPARSE_OID,
LOFC_OBJECT_TYPE,
LOFC_COMBINE,
LOFC__COUNT /* must be last */
};
/*
* Returns a configuration key suitable for describing the given object filter,
* e.g.: "blob:none", "combine", etc.
*/
const char *list_object_filter_config_name(enum list_objects_filter_choice c);
struct list_objects_filter_options {
/*
* 'filter_spec' is the raw argument value given on the command line
* or protocol request. (The part after the "--keyword=".) For
* commands that launch filtering sub-processes, or for communication
* over the network, don't use this value; use the result of
* expand_list_objects_filter_spec() instead.
* To get the raw filter spec given by the user, use the result of
* list_objects_filter_spec().
*/
struct strbuf filter_spec;
/*
* 'choice' is determined by parsing the filter-spec. This indicates
* the filtering algorithm to use.
*/
enum list_objects_filter_choice choice;
/*
* Choice is LOFC_DISABLED because "--no-filter" was requested.
*/
unsigned int no_filter : 1;
/*
* BEGIN choice-specific parsed values from within the filter-spec. Only
* some values will be defined for any given choice.
*/
list-objects-filter: delay parsing of sparse oid The list-objects-filter code has two steps to its initialization: 1. parse_list_objects_filter() makes sure the spec is a filter we know about and is syntactically correct. This step is done by "rev-list" or "upload-pack" that is going to apply a filter, but also by "git clone" or "git fetch" before they send the spec across the wire. 2. list_objects_filter__init() runs the type-specific initialization (using function pointers established in step 1). This happens at the start of traverse_commit_list_filtered(), when we're about to actually use the filter. It's a good idea to parse as much as we can in step 1, in order to catch problems early (e.g., a blob size limit that isn't a number). But one thing we _shouldn't_ do is resolve any oids at that step (e.g., for sparse-file contents specified by oid). In the case of a fetch, the oid has to be resolved on the remote side. The current code does resolve the oid during the parse phase, but ignores any error (which we must do, because we might just be sending the spec across the wire). This leads to two bugs: - if we're not in a repository (e.g., because it's git-clone parsing the spec), then we trigger a BUG() trying to resolve the name - if we did hit the error case, we still have to notice that later and bail. The code path in rev-list handles this, but the one in upload-pack does not, leading to a segfault. We can fix both by moving the oid resolution into the sparse-oid init function. At that point we know we have a repository (because we're about to traverse), and handling the error there fixes the segfault. As a bonus, we can drop the NULL sparse_oid_value check in rev-list, since this is now handled in the sparse-oid-filter init function. Signed-off-by: Jeff King <peff@peff.net> Acked-by: Jeff Hostetler <jeffhost@microsoft.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2019-09-15 16:12:44 +00:00
char *sparse_oid_name;
unsigned long blob_limit_value;
unsigned long tree_exclude_depth;
enum object_type object_type;
/* LOFC_COMBINE values */
/* This array contains all the subfilters which this filter combines. */
size_t sub_nr, sub_alloc;
struct list_objects_filter_options *sub;
/*
* END choice-specific parsed values.
*/
};
#define LIST_OBJECTS_FILTER_INIT { .filter_spec = STRBUF_INIT }
list-objects-filter: add and use initializers In 7e2619d8ff (list_objects_filter_options: plug leak of filter_spec strings, 2022-09-08), we noted that the filter_spec string_list was inconsistent in how it handled memory ownership of strings stored in the list. The fix there was a bit of a band-aid to set the "strdup_strings" variable right before adding anything. That works OK, and it lets the users of the API continue to zero-initialize the struct. But it makes the code a bit hard to follow and accident-prone, as any other spots appending the filter_spec need to think about whether to set the strdup_strings value, too (there's one such spot in partial_clone_get_default_filter_spec(), which is probably a possible memory leak). So let's do that full cleanup now. We'll introduce a LIST_OBJECTS_FILTER_INIT macro and matching function, and use them as appropriate (though it is for the "_options" struct, this matches the corresponding list_objects_filter_release() function). This is harder than it seems! Many other structs, like git_transport_data, embed the filter struct. So they need to initialize it themselves even if the rest of the enclosing struct is OK with zero-initialization. I found all of the relevant spots by grepping manually for declarations of list_objects_filter_options. And then doing so recursively for structs which embed it, and ones which embed those, and so on. I'm pretty sure I got everything, but there's no change that would alert the compiler if any topics in flight added new declarations. To catch this case, we now double-check in the parsing function that things were initialized as expected and BUG() if appropriate. Signed-off-by: Jeff King <peff@peff.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-09-11 05:03:07 +00:00
void list_objects_filter_init(struct list_objects_filter_options *filter_options);
/*
* Parse value of the argument to the "filter" keyword.
* On the command line this looks like:
* --filter=<arg>
* and in the pack protocol as:
* "filter" SP <arg>
*
* The filter keyword will be used by many commands.
* See Documentation/rev-list-options.txt for allowed values for <arg>.
*
* Capture the given arg as the "filter_spec". This can be forwarded to
* subordinate commands when necessary (although it's better to pass it through
* expand_list_objects_filter_spec() first). We also "intern" the arg for the
* convenience of the current command.
*/
int gently_parse_list_objects_filter(
struct list_objects_filter_options *filter_options,
const char *arg,
struct strbuf *errbuf);
void list_objects_filter_die_if_populated(
struct list_objects_filter_options *filter_options);
/*
* Parses the filter spec string given by arg and either (1) simply places the
* result in filter_options if it is not yet populated or (2) combines it with
* the filter already in filter_options if it is already populated. In the case
* of (2), the filter specs are combined as if specified with 'combine:'.
*
* Dies and prints a user-facing message if an error occurs.
*/
void parse_list_objects_filter(
struct list_objects_filter_options *filter_options,
const char *arg);
pack-objects: lazily set up "struct rev_info", don't leak In the preceding [1] (pack-objects: move revs out of get_object_list(), 2022-03-22) the "repo_init_revisions()" was moved to cmd_pack_objects() so that it unconditionally took place for all invocations of "git pack-objects". We'd thus start leaking memory, which is easily reproduced in e.g. git.git by feeding e83c5163316 (Initial revision of "git", the information manager from hell, 2005-04-07) to "git pack-objects"; $ echo e83c5163316f89bfbde7d9ab23ca2e25604af290 | ./git pack-objects initial [...] ==19130==ERROR: LeakSanitizer: detected memory leaks Direct leak of 7120 byte(s) in 1 object(s) allocated from: #0 0x455308 in __interceptor_malloc (/home/avar/g/git/git+0x455308) #1 0x75b399 in do_xmalloc /home/avar/g/git/wrapper.c:41:8 #2 0x75b356 in xmalloc /home/avar/g/git/wrapper.c:62:9 #3 0x5d7609 in prep_parse_options /home/avar/g/git/diff.c:5647:2 #4 0x5d415a in repo_diff_setup /home/avar/g/git/diff.c:4621:2 #5 0x6dffbb in repo_init_revisions /home/avar/g/git/revision.c:1853:2 #6 0x4f599d in cmd_pack_objects /home/avar/g/git/builtin/pack-objects.c:3980:2 #7 0x4592ca in run_builtin /home/avar/g/git/git.c:465:11 #8 0x457d81 in handle_builtin /home/avar/g/git/git.c:718:3 #9 0x458ca5 in run_argv /home/avar/g/git/git.c:785:4 #10 0x457b40 in cmd_main /home/avar/g/git/git.c:916:19 #11 0x562259 in main /home/avar/g/git/common-main.c:56:11 #12 0x7fce792ac7ec in __libc_start_main csu/../csu/libc-start.c:332:16 #13 0x4300f9 in _start (/home/avar/g/git/git+0x4300f9) SUMMARY: LeakSanitizer: 7120 byte(s) leaked in 1 allocation(s). Aborted Narrowly fixing that commit would have been easy, just add call repo_init_revisions() right before get_object_list(), which is effectively what was done before that commit. But an unstated constraint when setting it up early is that it was needed for the subsequent [2] (pack-objects: parse --filter directly into revs.filter, 2022-03-22), i.e. we might have a --filter command-line option, and need to either have the "struct rev_info" setup when we encounter that option, or later. Let's just change the control flow so that we'll instead set up the "struct rev_info" only when we need it. Doing so leads to a bit more verbosity, but it's a lot clearer what we're doing and why. An earlier version of this commit[3] went behind opt_parse_list_objects_filter()'s back by faking up a "struct option" before calling it. Let's avoid that and instead create a blessed API for this pattern. We could furthermore combine the two get_object_list() invocations here by having repo_init_revisions() invoked on &pfd.revs, but I think clearly separating the two makes the flow clearer. Likewise redundantly but explicitly (i.e. redundant v.s. a "{ 0 }") "0" to "have_revs" early in cmd_pack_objects(). While we're at it add parentheses around the arguments to the OPT_* macros in in list-objects-filter-options.h, as we need to change those lines anyway. It doesn't matter in this case, but is good general practice. 1. https://lore.kernel.org/git/619b757d98465dbc4995bdc11a5282fbfcbd3daa.1647970119.git.gitgitgadget@gmail.com 2. https://lore.kernel.org/git/97de926904988b89b5663bd4c59c011a1723a8f5.1647970119.git.gitgitgadget@gmail.com 3. https://lore.kernel.org/git/patch-1.1-193534b0f07-20220325T121715Z-avarab@gmail.com/ Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
2022-03-28 15:43:18 +00:00
/**
* The opt->value to opt_parse_list_objects_filter() is either a
* "struct list_objects_filter_option *" when using
* OPT_PARSE_LIST_OBJECTS_FILTER().
*/
int opt_parse_list_objects_filter(const struct option *opt,
const char *arg, int unset);
#define OPT_PARSE_LIST_OBJECTS_FILTER(fo) \
OPT_CALLBACK(0, "filter", (fo), N_("args"), \
N_("object filtering"), opt_parse_list_objects_filter)
/*
* Translates abbreviated numbers in the filter's filter_spec into their
* fully-expanded forms (e.g., "limit:blob=1k" becomes "limit:blob=1024").
* Returns a string owned by the list_objects_filter_options object.
*
* This form should be used instead of the raw list_objects_filter_spec()
* value when communicating with a remote process or subprocess.
*/
const char *expand_list_objects_filter_spec(
struct list_objects_filter_options *filter);
/*
* Returns the filter spec string more or less in the form as the user
* entered it. This form of the filter_spec can be used in user-facing
* messages. Returns a string owned by the list_objects_filter_options
* object.
*/
const char *list_objects_filter_spec(
struct list_objects_filter_options *filter);
void list_objects_filter_release(
struct list_objects_filter_options *filter_options);
static inline void list_objects_filter_set_no_filter(
struct list_objects_filter_options *filter_options)
{
list_objects_filter_release(filter_options);
filter_options->no_filter = 1;
}
void partial_clone_register(
const char *remote,
struct list_objects_filter_options *filter_options);
void partial_clone_get_default_filter_spec(
struct list_objects_filter_options *filter_options,
const char *remote);
void list_objects_filter_copy(
struct list_objects_filter_options *dest,
const struct list_objects_filter_options *src);
#endif /* LIST_OBJECTS_FILTER_OPTIONS_H */