ref-cache: use a callback function to fill the cache

It is a leveling violation for `ref_cache` to know about
`files_ref_store` or that it should call `read_loose_refs()` to lazily
fill cache directories. So instead, have its constructor take as an
argument a callback function that it should use for lazy-filling, and
change `files_ref_store` to supply a pointer to function
`read_loose_refs` (renamed to `loose_fill_ref_dir`) when creating the
ref cache for its loose refs.

This means that we can generify the type of the back-pointer in
`struct ref_cache` from `files_ref_store` to `ref_store`.

Signed-off-by: Michael Haggerty <mhagger@alum.mit.edu>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
This commit is contained in:
Michael Haggerty 2017-04-16 08:41:34 +02:00 committed by Junio C Hamano
parent e00d1a4ff7
commit df30875987
3 changed files with 38 additions and 13 deletions

View file

@ -386,7 +386,7 @@ static struct packed_ref_cache *get_packed_ref_cache(struct files_ref_store *ref
refs->packed = xcalloc(1, sizeof(*refs->packed));
acquire_packed_ref_cache(refs->packed);
refs->packed->cache = create_ref_cache(refs);
refs->packed->cache = create_ref_cache(&refs->base, NULL);
refs->packed->cache->root->flag &= ~REF_INCOMPLETE;
f = fopen(packed_refs_file, "r");
if (f) {
@ -430,9 +430,11 @@ static void add_packed_ref(struct files_ref_store *refs,
* (without recursing). dirname must end with '/'. dir must be the
* directory entry corresponding to dirname.
*/
void read_loose_refs(const char *dirname, struct ref_dir *dir)
static void loose_fill_ref_dir(struct ref_store *ref_store,
struct ref_dir *dir, const char *dirname)
{
struct files_ref_store *refs = dir->cache->ref_store;
struct files_ref_store *refs =
files_downcast(ref_store, REF_STORE_READ, "fill_ref_dir");
DIR *d;
struct dirent *de;
int dirnamelen = strlen(dirname);
@ -515,7 +517,7 @@ static struct ref_dir *get_loose_refs(struct files_ref_store *refs)
* are about to read the only subdirectory that can
* hold references:
*/
refs->loose = create_ref_cache(refs);
refs->loose = create_ref_cache(&refs->base, loose_fill_ref_dir);
/* We're going to fill the top level ourselves: */
refs->loose->root->flag &= ~REF_INCOMPLETE;

View file

@ -4,9 +4,6 @@
#include "ref-cache.h"
#include "../iterator.h"
/* FIXME: This declaration shouldn't be here */
void read_loose_refs(const char *dirname, struct ref_dir *dir);
void add_entry_to_dir(struct ref_dir *dir, struct ref_entry *entry)
{
ALLOC_GROW(dir->entries, dir->nr + 1, dir->alloc);
@ -25,7 +22,10 @@ struct ref_dir *get_ref_dir(struct ref_entry *entry)
assert(entry->flag & REF_DIR);
dir = &entry->u.subdir;
if (entry->flag & REF_INCOMPLETE) {
read_loose_refs(entry->name, dir);
if (!dir->cache->fill_ref_dir)
die("BUG: incomplete ref_store without fill_ref_dir function");
dir->cache->fill_ref_dir(dir->cache->ref_store, dir, entry->name);
/*
* Manually add refs/bisect, which, being
@ -63,11 +63,13 @@ struct ref_entry *create_ref_entry(const char *refname,
return ref;
}
struct ref_cache *create_ref_cache(struct files_ref_store *refs)
struct ref_cache *create_ref_cache(struct ref_store *refs,
fill_ref_dir_fn *fill_ref_dir)
{
struct ref_cache *ret = xcalloc(1, sizeof(*ret));
ret->ref_store = refs;
ret->fill_ref_dir = fill_ref_dir;
ret->root = create_dir_entry(ret, "", 0, 1);
return ret;
}

View file

@ -1,11 +1,27 @@
#ifndef REFS_REF_CACHE_H
#define REFS_REF_CACHE_H
struct ref_dir;
/*
* If this ref_cache is filled lazily, this function is used to load
* information into the specified ref_dir (shallow or deep, at the
* option of the ref_store). dirname includes a trailing slash.
*/
typedef void fill_ref_dir_fn(struct ref_store *ref_store,
struct ref_dir *dir, const char *dirname);
struct ref_cache {
struct ref_entry *root;
/* A pointer to the files_ref_store whose cache this is: */
struct files_ref_store *ref_store;
/* A pointer to the ref_store whose cache this is: */
struct ref_store *ref_store;
/*
* Function used (if necessary) to lazily-fill cache. May be
* NULL.
*/
fill_ref_dir_fn *fill_ref_dir;
};
/*
@ -174,9 +190,14 @@ struct ref_entry *create_ref_entry(const char *refname,
/*
* Return a pointer to a new `ref_cache`. Its top-level starts out
* marked incomplete.
* marked incomplete. If `fill_ref_dir` is non-NULL, it is the
* function called to fill in incomplete directories in the
* `ref_cache` when they are accessed. If it is NULL, then the whole
* `ref_cache` must be filled (including clearing its directories'
* `REF_INCOMPLETE` bits) before it is used.
*/
struct ref_cache *create_ref_cache(struct files_ref_store *refs);
struct ref_cache *create_ref_cache(struct ref_store *refs,
fill_ref_dir_fn *fill_ref_dir);
/*
* Free the `ref_cache` and all of its associated data.