git/builtin/prune.c
Neeraj Singh b3cecf49ea tmp-objdir: new API for creating temporary writable databases
The tmp_objdir API provides the ability to create temporary object
directories, but was designed with the goal of having subprocesses
access these object stores, followed by the main process migrating
objects from it to the main object store or just deleting it.  The
subprocesses would view it as their primary datastore and write to it.

Here we add the tmp_objdir_replace_primary_odb function that replaces
the current process's writable "main" object directory with the
specified one. The previous main object directory is restored in either
tmp_objdir_migrate or tmp_objdir_destroy.

For the --remerge-diff usecase, add a new `will_destroy` flag in `struct
object_database` to mark ephemeral object databases that do not require
fsync durability.

Add 'git prune' support for removing temporary object databases, and
make sure that they have a name starting with tmp_ and containing an
operation-specific name.

Based-on-patch-by: Elijah Newren <newren@gmail.com>

Signed-off-by: Neeraj Singh <neerajsi@microsoft.com>
Reviewed-by: Elijah Newren <newren@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-12-08 14:06:36 -08:00

202 lines
4.9 KiB
C

#include "cache.h"
#include "commit.h"
#include "diff.h"
#include "revision.h"
#include "builtin.h"
#include "reachable.h"
#include "parse-options.h"
#include "progress.h"
#include "prune-packed.h"
#include "object-store.h"
#include "shallow.h"
static const char * const prune_usage[] = {
N_("git prune [-n] [-v] [--progress] [--expire <time>] [--] [<head>...]"),
NULL
};
static int show_only;
static int verbose;
static timestamp_t expire;
static int show_progress = -1;
static int prune_tmp_file(const char *fullpath)
{
struct stat st;
if (lstat(fullpath, &st))
return error("Could not stat '%s'", fullpath);
if (st.st_mtime > expire)
return 0;
if (S_ISDIR(st.st_mode)) {
if (show_only || verbose)
printf("Removing stale temporary directory %s\n", fullpath);
if (!show_only) {
struct strbuf remove_dir_buf = STRBUF_INIT;
strbuf_addstr(&remove_dir_buf, fullpath);
remove_dir_recursively(&remove_dir_buf, 0);
strbuf_release(&remove_dir_buf);
}
} else {
if (show_only || verbose)
printf("Removing stale temporary file %s\n", fullpath);
if (!show_only)
unlink_or_warn(fullpath);
}
return 0;
}
static void perform_reachability_traversal(struct rev_info *revs)
{
static int initialized;
struct progress *progress = NULL;
if (initialized)
return;
if (show_progress)
progress = start_delayed_progress(_("Checking connectivity"), 0);
mark_reachable_objects(revs, 1, expire, progress);
stop_progress(&progress);
initialized = 1;
}
static int is_object_reachable(const struct object_id *oid,
struct rev_info *revs)
{
struct object *obj;
perform_reachability_traversal(revs);
obj = lookup_object(the_repository, oid);
return obj && (obj->flags & SEEN);
}
static int prune_object(const struct object_id *oid, const char *fullpath,
void *data)
{
struct rev_info *revs = data;
struct stat st;
if (is_object_reachable(oid, revs))
return 0;
if (lstat(fullpath, &st)) {
/* report errors, but do not stop pruning */
error("Could not stat '%s'", fullpath);
return 0;
}
if (st.st_mtime > expire)
return 0;
if (show_only || verbose) {
enum object_type type = oid_object_info(the_repository, oid,
NULL);
printf("%s %s\n", oid_to_hex(oid),
(type > 0) ? type_name(type) : "unknown");
}
if (!show_only)
unlink_or_warn(fullpath);
return 0;
}
static int prune_cruft(const char *basename, const char *path, void *data)
{
if (starts_with(basename, "tmp_obj_"))
prune_tmp_file(path);
else
fprintf(stderr, "bad sha1 file: %s\n", path);
return 0;
}
static int prune_subdir(unsigned int nr, const char *path, void *data)
{
if (!show_only)
rmdir(path);
return 0;
}
/*
* Write errors (particularly out of space) can result in
* failed temporary packs (and more rarely indexes and other
* files beginning with "tmp_") accumulating in the object
* and the pack directories.
*/
static void remove_temporary_files(const char *path)
{
DIR *dir;
struct dirent *de;
dir = opendir(path);
if (!dir) {
fprintf(stderr, "Unable to open directory %s\n", path);
return;
}
while ((de = readdir(dir)) != NULL)
if (starts_with(de->d_name, "tmp_"))
prune_tmp_file(mkpath("%s/%s", path, de->d_name));
closedir(dir);
}
int cmd_prune(int argc, const char **argv, const char *prefix)
{
struct rev_info revs;
int exclude_promisor_objects = 0;
const struct option options[] = {
OPT__DRY_RUN(&show_only, N_("do not remove, show only")),
OPT__VERBOSE(&verbose, N_("report pruned objects")),
OPT_BOOL(0, "progress", &show_progress, N_("show progress")),
OPT_EXPIRY_DATE(0, "expire", &expire,
N_("expire objects older than <time>")),
OPT_BOOL(0, "exclude-promisor-objects", &exclude_promisor_objects,
N_("limit traversal to objects outside promisor packfiles")),
OPT_END()
};
char *s;
expire = TIME_MAX;
save_commit_buffer = 0;
read_replace_refs = 0;
ref_paranoia = 1;
repo_init_revisions(the_repository, &revs, prefix);
argc = parse_options(argc, argv, prefix, options, prune_usage, 0);
if (repository_format_precious_objects)
die(_("cannot prune in a precious-objects repo"));
while (argc--) {
struct object_id oid;
const char *name = *argv++;
if (!get_oid(name, &oid)) {
struct object *object = parse_object_or_die(&oid,
name);
add_pending_object(&revs, object, "");
}
else
die("unrecognized argument: %s", name);
}
if (show_progress == -1)
show_progress = isatty(2);
if (exclude_promisor_objects) {
fetch_if_missing = 0;
revs.exclude_promisor_objects = 1;
}
for_each_loose_file_in_objdir(get_object_directory(), prune_object,
prune_cruft, prune_subdir, &revs);
prune_packed_objects(show_only ? PRUNE_PACKED_DRY_RUN : 0);
remove_temporary_files(get_object_directory());
s = mkpathdup("%s/pack", get_object_directory());
remove_temporary_files(s);
free(s);
if (is_repository_shallow(the_repository)) {
perform_reachability_traversal(&revs);
prune_shallow(show_only ? PRUNE_SHOW_ONLY : 0);
}
return 0;
}