git-commit-vandalism/submodule-config.c
Brandon Williams ff6f1f564c submodule-config: lazy-load a repository's .gitmodules file
In order to use the submodule-config subsystem, callers first need to
initialize it by calling 'repo_read_gitmodules()' or
'gitmodules_config()' (which just redirects to
'repo_read_gitmodules()').  There are a couple of callers who need to
load an explicit revision of the repository's .gitmodules file (grep) or
need to modify the .gitmodules file so they would need to load it before
modify the file (checkout), but the majority of callers are simply
reading the .gitmodules file present in the working tree.  For the
common case it would be nice to avoid the boilerplate of initializing
the submodule-config system before using it, so instead let's perform
lazy-loading of the submodule-config system.

Remove the calls to reading the gitmodules file from ls-files to show
that lazy-loading the .gitmodules file works.

Signed-off-by: Brandon Williams <bmwill@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-08-03 13:11:01 -07:00

644 lines
17 KiB
C

#include "cache.h"
#include "repository.h"
#include "config.h"
#include "submodule-config.h"
#include "submodule.h"
#include "strbuf.h"
#include "parse-options.h"
/*
* submodule cache lookup structure
* There is one shared set of 'struct submodule' entries which can be
* looked up by their sha1 blob id of the .gitmodule file and either
* using path or name as key.
* for_path stores submodule entries with path as key
* for_name stores submodule entries with name as key
*/
struct submodule_cache {
struct hashmap for_path;
struct hashmap for_name;
unsigned initialized:1;
unsigned gitmodules_read:1;
};
/*
* thin wrapper struct needed to insert 'struct submodule' entries to
* the hashmap
*/
struct submodule_entry {
struct hashmap_entry ent;
struct submodule *config;
};
enum lookup_type {
lookup_name,
lookup_path
};
static int config_path_cmp(const void *unused_cmp_data,
const struct submodule_entry *a,
const struct submodule_entry *b,
const void *unused_keydata)
{
return strcmp(a->config->path, b->config->path) ||
hashcmp(a->config->gitmodules_sha1, b->config->gitmodules_sha1);
}
static int config_name_cmp(const void *unused_cmp_data,
const struct submodule_entry *a,
const struct submodule_entry *b,
const void *unused_keydata)
{
return strcmp(a->config->name, b->config->name) ||
hashcmp(a->config->gitmodules_sha1, b->config->gitmodules_sha1);
}
static struct submodule_cache *submodule_cache_alloc(void)
{
return xcalloc(1, sizeof(struct submodule_cache));
}
static void submodule_cache_init(struct submodule_cache *cache)
{
hashmap_init(&cache->for_path, (hashmap_cmp_fn) config_path_cmp, NULL, 0);
hashmap_init(&cache->for_name, (hashmap_cmp_fn) config_name_cmp, NULL, 0);
cache->initialized = 1;
}
static void free_one_config(struct submodule_entry *entry)
{
free((void *) entry->config->path);
free((void *) entry->config->name);
free((void *) entry->config->branch);
free((void *) entry->config->update_strategy.command);
free(entry->config);
}
static void submodule_cache_clear(struct submodule_cache *cache)
{
struct hashmap_iter iter;
struct submodule_entry *entry;
if (!cache->initialized)
return;
/*
* We iterate over the name hash here to be symmetric with the
* allocation of struct submodule entries. Each is allocated by
* their .gitmodule blob sha1 and submodule name.
*/
hashmap_iter_init(&cache->for_name, &iter);
while ((entry = hashmap_iter_next(&iter)))
free_one_config(entry);
hashmap_free(&cache->for_path, 1);
hashmap_free(&cache->for_name, 1);
cache->initialized = 0;
cache->gitmodules_read = 0;
}
void submodule_cache_free(struct submodule_cache *cache)
{
submodule_cache_clear(cache);
free(cache);
}
static unsigned int hash_sha1_string(const unsigned char *sha1,
const char *string)
{
return memhash(sha1, 20) + strhash(string);
}
static void cache_put_path(struct submodule_cache *cache,
struct submodule *submodule)
{
unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
submodule->path);
struct submodule_entry *e = xmalloc(sizeof(*e));
hashmap_entry_init(e, hash);
e->config = submodule;
hashmap_put(&cache->for_path, e);
}
static void cache_remove_path(struct submodule_cache *cache,
struct submodule *submodule)
{
unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
submodule->path);
struct submodule_entry e;
struct submodule_entry *removed;
hashmap_entry_init(&e, hash);
e.config = submodule;
removed = hashmap_remove(&cache->for_path, &e, NULL);
free(removed);
}
static void cache_add(struct submodule_cache *cache,
struct submodule *submodule)
{
unsigned int hash = hash_sha1_string(submodule->gitmodules_sha1,
submodule->name);
struct submodule_entry *e = xmalloc(sizeof(*e));
hashmap_entry_init(e, hash);
e->config = submodule;
hashmap_add(&cache->for_name, e);
}
static const struct submodule *cache_lookup_path(struct submodule_cache *cache,
const unsigned char *gitmodules_sha1, const char *path)
{
struct submodule_entry *entry;
unsigned int hash = hash_sha1_string(gitmodules_sha1, path);
struct submodule_entry key;
struct submodule key_config;
hashcpy(key_config.gitmodules_sha1, gitmodules_sha1);
key_config.path = path;
hashmap_entry_init(&key, hash);
key.config = &key_config;
entry = hashmap_get(&cache->for_path, &key, NULL);
if (entry)
return entry->config;
return NULL;
}
static struct submodule *cache_lookup_name(struct submodule_cache *cache,
const unsigned char *gitmodules_sha1, const char *name)
{
struct submodule_entry *entry;
unsigned int hash = hash_sha1_string(gitmodules_sha1, name);
struct submodule_entry key;
struct submodule key_config;
hashcpy(key_config.gitmodules_sha1, gitmodules_sha1);
key_config.name = name;
hashmap_entry_init(&key, hash);
key.config = &key_config;
entry = hashmap_get(&cache->for_name, &key, NULL);
if (entry)
return entry->config;
return NULL;
}
static int name_and_item_from_var(const char *var, struct strbuf *name,
struct strbuf *item)
{
const char *subsection, *key;
int subsection_len, parse;
parse = parse_config_key(var, "submodule", &subsection,
&subsection_len, &key);
if (parse < 0 || !subsection)
return 0;
strbuf_add(name, subsection, subsection_len);
strbuf_addstr(item, key);
return 1;
}
static struct submodule *lookup_or_create_by_name(struct submodule_cache *cache,
const unsigned char *gitmodules_sha1, const char *name)
{
struct submodule *submodule;
struct strbuf name_buf = STRBUF_INIT;
submodule = cache_lookup_name(cache, gitmodules_sha1, name);
if (submodule)
return submodule;
submodule = xmalloc(sizeof(*submodule));
strbuf_addstr(&name_buf, name);
submodule->name = strbuf_detach(&name_buf, NULL);
submodule->path = NULL;
submodule->url = NULL;
submodule->update_strategy.type = SM_UPDATE_UNSPECIFIED;
submodule->update_strategy.command = NULL;
submodule->fetch_recurse = RECURSE_SUBMODULES_NONE;
submodule->ignore = NULL;
submodule->branch = NULL;
submodule->recommend_shallow = -1;
hashcpy(submodule->gitmodules_sha1, gitmodules_sha1);
cache_add(cache, submodule);
return submodule;
}
static int parse_fetch_recurse(const char *opt, const char *arg,
int die_on_error)
{
switch (git_config_maybe_bool(opt, arg)) {
case 1:
return RECURSE_SUBMODULES_ON;
case 0:
return RECURSE_SUBMODULES_OFF;
default:
if (!strcmp(arg, "on-demand"))
return RECURSE_SUBMODULES_ON_DEMAND;
if (die_on_error)
die("bad %s argument: %s", opt, arg);
else
return RECURSE_SUBMODULES_ERROR;
}
}
int parse_submodule_fetchjobs(const char *var, const char *value)
{
int fetchjobs = git_config_int(var, value);
if (fetchjobs < 0)
die(_("negative values not allowed for submodule.fetchjobs"));
return fetchjobs;
}
int parse_fetch_recurse_submodules_arg(const char *opt, const char *arg)
{
return parse_fetch_recurse(opt, arg, 1);
}
int option_fetch_parse_recurse_submodules(const struct option *opt,
const char *arg, int unset)
{
int *v;
if (!opt->value)
return -1;
v = opt->value;
if (unset) {
*v = RECURSE_SUBMODULES_OFF;
} else {
if (arg)
*v = parse_fetch_recurse_submodules_arg(opt->long_name, arg);
else
*v = RECURSE_SUBMODULES_ON;
}
return 0;
}
static int parse_update_recurse(const char *opt, const char *arg,
int die_on_error)
{
switch (git_config_maybe_bool(opt, arg)) {
case 1:
return RECURSE_SUBMODULES_ON;
case 0:
return RECURSE_SUBMODULES_OFF;
default:
if (die_on_error)
die("bad %s argument: %s", opt, arg);
return RECURSE_SUBMODULES_ERROR;
}
}
int parse_update_recurse_submodules_arg(const char *opt, const char *arg)
{
return parse_update_recurse(opt, arg, 1);
}
static int parse_push_recurse(const char *opt, const char *arg,
int die_on_error)
{
switch (git_config_maybe_bool(opt, arg)) {
case 1:
/* There's no simple "on" value when pushing */
if (die_on_error)
die("bad %s argument: %s", opt, arg);
else
return RECURSE_SUBMODULES_ERROR;
case 0:
return RECURSE_SUBMODULES_OFF;
default:
if (!strcmp(arg, "on-demand"))
return RECURSE_SUBMODULES_ON_DEMAND;
else if (!strcmp(arg, "check"))
return RECURSE_SUBMODULES_CHECK;
else if (!strcmp(arg, "only"))
return RECURSE_SUBMODULES_ONLY;
else if (die_on_error)
die("bad %s argument: %s", opt, arg);
else
return RECURSE_SUBMODULES_ERROR;
}
}
int parse_push_recurse_submodules_arg(const char *opt, const char *arg)
{
return parse_push_recurse(opt, arg, 1);
}
static void warn_multiple_config(const unsigned char *treeish_name,
const char *name, const char *option)
{
const char *commit_string = "WORKTREE";
if (treeish_name)
commit_string = sha1_to_hex(treeish_name);
warning("%s:.gitmodules, multiple configurations found for "
"'submodule.%s.%s'. Skipping second one!",
commit_string, name, option);
}
struct parse_config_parameter {
struct submodule_cache *cache;
const unsigned char *treeish_name;
const unsigned char *gitmodules_sha1;
int overwrite;
};
static int parse_config(const char *var, const char *value, void *data)
{
struct parse_config_parameter *me = data;
struct submodule *submodule;
struct strbuf name = STRBUF_INIT, item = STRBUF_INIT;
int ret = 0;
/* this also ensures that we only parse submodule entries */
if (!name_and_item_from_var(var, &name, &item))
return 0;
submodule = lookup_or_create_by_name(me->cache,
me->gitmodules_sha1,
name.buf);
if (!strcmp(item.buf, "path")) {
if (!value)
ret = config_error_nonbool(var);
else if (!me->overwrite && submodule->path)
warn_multiple_config(me->treeish_name, submodule->name,
"path");
else {
if (submodule->path)
cache_remove_path(me->cache, submodule);
free((void *) submodule->path);
submodule->path = xstrdup(value);
cache_put_path(me->cache, submodule);
}
} else if (!strcmp(item.buf, "fetchrecursesubmodules")) {
/* when parsing worktree configurations we can die early */
int die_on_error = is_null_sha1(me->gitmodules_sha1);
if (!me->overwrite &&
submodule->fetch_recurse != RECURSE_SUBMODULES_NONE)
warn_multiple_config(me->treeish_name, submodule->name,
"fetchrecursesubmodules");
else
submodule->fetch_recurse = parse_fetch_recurse(
var, value,
die_on_error);
} else if (!strcmp(item.buf, "ignore")) {
if (!value)
ret = config_error_nonbool(var);
else if (!me->overwrite && submodule->ignore)
warn_multiple_config(me->treeish_name, submodule->name,
"ignore");
else if (strcmp(value, "untracked") &&
strcmp(value, "dirty") &&
strcmp(value, "all") &&
strcmp(value, "none"))
warning("Invalid parameter '%s' for config option "
"'submodule.%s.ignore'", value, name.buf);
else {
free((void *) submodule->ignore);
submodule->ignore = xstrdup(value);
}
} else if (!strcmp(item.buf, "url")) {
if (!value) {
ret = config_error_nonbool(var);
} else if (!me->overwrite && submodule->url) {
warn_multiple_config(me->treeish_name, submodule->name,
"url");
} else {
free((void *) submodule->url);
submodule->url = xstrdup(value);
}
} else if (!strcmp(item.buf, "update")) {
if (!value)
ret = config_error_nonbool(var);
else if (!me->overwrite &&
submodule->update_strategy.type != SM_UPDATE_UNSPECIFIED)
warn_multiple_config(me->treeish_name, submodule->name,
"update");
else if (parse_submodule_update_strategy(value,
&submodule->update_strategy) < 0)
die(_("invalid value for %s"), var);
} else if (!strcmp(item.buf, "shallow")) {
if (!me->overwrite && submodule->recommend_shallow != -1)
warn_multiple_config(me->treeish_name, submodule->name,
"shallow");
else
submodule->recommend_shallow =
git_config_bool(var, value);
} else if (!strcmp(item.buf, "branch")) {
if (!me->overwrite && submodule->branch)
warn_multiple_config(me->treeish_name, submodule->name,
"branch");
else {
free((void *)submodule->branch);
submodule->branch = xstrdup(value);
}
}
strbuf_release(&name);
strbuf_release(&item);
return ret;
}
static int gitmodule_oid_from_commit(const struct object_id *treeish_name,
struct object_id *gitmodules_oid,
struct strbuf *rev)
{
int ret = 0;
if (is_null_oid(treeish_name)) {
oidclr(gitmodules_oid);
return 1;
}
strbuf_addf(rev, "%s:.gitmodules", oid_to_hex(treeish_name));
if (get_oid(rev->buf, gitmodules_oid) >= 0)
ret = 1;
return ret;
}
/* This does a lookup of a submodule configuration by name or by path
* (key) with on-demand reading of the appropriate .gitmodules from
* revisions.
*/
static const struct submodule *config_from(struct submodule_cache *cache,
const struct object_id *treeish_name, const char *key,
enum lookup_type lookup_type)
{
struct strbuf rev = STRBUF_INIT;
unsigned long config_size;
char *config = NULL;
struct object_id oid;
enum object_type type;
const struct submodule *submodule = NULL;
struct parse_config_parameter parameter;
/*
* If any parameter except the cache is a NULL pointer just
* return the first submodule. Can be used to check whether
* there are any submodules parsed.
*/
if (!treeish_name || !key) {
struct hashmap_iter iter;
struct submodule_entry *entry;
entry = hashmap_iter_first(&cache->for_name, &iter);
if (!entry)
return NULL;
return entry->config;
}
if (!gitmodule_oid_from_commit(treeish_name, &oid, &rev))
goto out;
switch (lookup_type) {
case lookup_name:
submodule = cache_lookup_name(cache, oid.hash, key);
break;
case lookup_path:
submodule = cache_lookup_path(cache, oid.hash, key);
break;
}
if (submodule)
goto out;
config = read_sha1_file(oid.hash, &type, &config_size);
if (!config || type != OBJ_BLOB)
goto out;
/* fill the submodule config into the cache */
parameter.cache = cache;
parameter.treeish_name = treeish_name->hash;
parameter.gitmodules_sha1 = oid.hash;
parameter.overwrite = 0;
git_config_from_mem(parse_config, CONFIG_ORIGIN_SUBMODULE_BLOB, rev.buf,
config, config_size, &parameter);
strbuf_release(&rev);
free(config);
switch (lookup_type) {
case lookup_name:
return cache_lookup_name(cache, oid.hash, key);
case lookup_path:
return cache_lookup_path(cache, oid.hash, key);
default:
return NULL;
}
out:
strbuf_release(&rev);
free(config);
return submodule;
}
static void submodule_cache_check_init(struct repository *repo)
{
if (repo->submodule_cache && repo->submodule_cache->initialized)
return;
if (!repo->submodule_cache)
repo->submodule_cache = submodule_cache_alloc();
submodule_cache_init(repo->submodule_cache);
}
static int gitmodules_cb(const char *var, const char *value, void *data)
{
struct repository *repo = data;
struct parse_config_parameter parameter;
parameter.cache = repo->submodule_cache;
parameter.treeish_name = NULL;
parameter.gitmodules_sha1 = null_sha1;
parameter.overwrite = 1;
return parse_config(var, value, &parameter);
}
void repo_read_gitmodules(struct repository *repo)
{
submodule_cache_check_init(repo);
if (repo->worktree) {
char *gitmodules;
if (repo_read_index(repo) < 0)
return;
gitmodules = repo_worktree_path(repo, GITMODULES_FILE);
if (!is_gitmodules_unmerged(repo->index))
git_config_from_file(gitmodules_cb, gitmodules, repo);
free(gitmodules);
}
repo->submodule_cache->gitmodules_read = 1;
}
void gitmodules_config_oid(const struct object_id *commit_oid)
{
struct strbuf rev = STRBUF_INIT;
struct object_id oid;
submodule_cache_check_init(the_repository);
if (gitmodule_oid_from_commit(commit_oid, &oid, &rev)) {
git_config_from_blob_oid(gitmodules_cb, rev.buf,
&oid, the_repository);
}
strbuf_release(&rev);
the_repository->submodule_cache->gitmodules_read = 1;
}
static void gitmodules_read_check(struct repository *repo)
{
submodule_cache_check_init(repo);
/* read the repo's .gitmodules file if it hasn't been already */
if (!repo->submodule_cache->gitmodules_read)
repo_read_gitmodules(repo);
}
const struct submodule *submodule_from_name(const struct object_id *treeish_name,
const char *name)
{
gitmodules_read_check(the_repository);
return config_from(the_repository->submodule_cache, treeish_name, name, lookup_name);
}
const struct submodule *submodule_from_path(const struct object_id *treeish_name,
const char *path)
{
gitmodules_read_check(the_repository);
return config_from(the_repository->submodule_cache, treeish_name, path, lookup_path);
}
const struct submodule *submodule_from_cache(struct repository *repo,
const struct object_id *treeish_name,
const char *key)
{
gitmodules_read_check(repo);
return config_from(repo->submodule_cache, treeish_name,
key, lookup_path);
}
void submodule_free(void)
{
if (the_repository->submodule_cache)
submodule_cache_clear(the_repository->submodule_cache);
}