| /*
* sai-builder com-warmcat-sai client protocol implementation
*
* Copyright (C) 2019 - 2020 Andy Green <andy@warmcat.com>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation:
* version 2.1 of the License.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
* MA 02110-1301 USA
*/
#include <libwebsockets.h>
#include <string.h>
#include <signal.h>
#include <assert.h>
#include "b-private.h"
#include <git2.h>
enum {
SRFS_REQUESTING,
SRFS_PROCESSING,
SRFS_FAILED,
SRFS_SUCCEEDED,
};
/*
* Request to do the remote -> local mirror action
*/
typedef struct sai_mirror_req {
lws_dll2_t list;
struct sai_nspawn *ns;
char path[100]; /* local mirror path */
char url[100];
char hash[130];
char ref[96];
int state;
} sai_mirror_req_t;
static void
sai_mirror_req_state_set(sai_mirror_req_t *req, int n)
{
lwsl_notice("%s: req %p: %d -> %d\n", __func__, req, req->state, n);
req->state = n;
}
enum {
SAIB_CHECKOUT_OK,
SAIB_CHECKOUT_NOT_IN_LOCAL_MIRROR,
SAIB_CHECKOUT_CHECKOUT_FAILED,
};
static int
sai_mirror_local_checkout(struct sai_nspawn *ns)
{
git_checkout_options co_opts = GIT_CHECKOUT_OPTIONS_INIT;
git_fetch_options opts = GIT_FETCH_OPTIONS_INIT;
git_repository *git_repo_build_specific = NULL;
char dp[512], spec[256], *paths[] = { spec };
git_strarray rfs = { paths, 1 };
git_object *treeish;
git_remote *remote;
int n, tries = 2;
/*
* Remove anything that was already in the build-specific dir
*/
lwsl_notice("%s: rm -rf %s\n", __func__, ns->inp);
lws_dir(ns->inp, NULL, lws_dir_rm_rf_cb);
/*
* Make sure the build-specific dir itself is left standing in there.
*
* We can only create files and dirs using the global sai:nobody
* credentials since we have dropped root long ago
*/
if (mkdir(ns->inp, 0755))
lwsl_notice("%s: mkdir %s failed\n", __func__, ns->inp);
/*
* Create the build-specific git dir and init it
*/
n = git_repository_init(&git_repo_build_specific, ns->inp, 0);
if (n) {
#if defined(SAI_HAVE_LIBGIT2_GIT_ERROR)
const git_error *e = git_error_last();
lwsl_err("%s: unable to init temp repo %s: %d %s\n",
__func__, ns->inp, n, e ? e->message : "?");
#else
lwsl_err("%s: unable to init temp repo %s: %d\n",
__func__, ns->inp, n);
#endif
return 1;
}
/*
* Attempt to fetch the ref we are interested in from our local mirror
*
* Create a temp remote against the destination repo
*/
if (git_remote_create_anonymous(&remote, git_repo_build_specific,
ns->path)) {
lwsl_err("%s: cant find remote %s\n", __func__,
ns->git_repo_url);
git_repository_free(git_repo_build_specific);
return 1;
}
lws_snprintf(spec, sizeof(spec), "ref-%s:ref-%s", ns->hash, ns->hash);
lwsl_notice("%s: Attempting to fetch %s from mirror to %s\n",
__func__, spec, ns->inp);
/*
* Fetch the tree from the local mirror to our local build repo
* This may take an open-ended amount of time
*/
#if defined(LIBGIT2_HAVE_GIT_PROXY_OPTIONS_INIT)
git_proxy_options_init(&opts.proxy_opts, GIT_PROXY_OPTIONS_VERSION);
#endif
n = git_remote_fetch(remote, &rfs, &opts, "fetch");
git_remote_free(remote);
if (n) {
lwsl_notice("%s: git_remote_fetch() says %d\n", __func__, n);
#if defined(SAI_HAVE_LIBGIT2_GIT_ERROR)
const git_error *e = git_error_last();
lwsl_err("%s: git_remote_fetch libgit err: %d %s\n",
__func__, n, e ? e->message : "?");
#endif
git_repository_free(git_repo_build_specific);
return SAIB_CHECKOUT_NOT_IN_LOCAL_MIRROR;
}
/*
* Check out the commit we fetched into the ephemeral local build dir...
* this should be a formality since we already retreived the ref into
* ephemeral local build dir's repo.
*/
lws_snprintf(spec, sizeof(spec), "ref-%s", ns->hash);
n = git_revparse_single(&treeish, git_repo_build_specific, spec);
if (n) {
lwsl_notice("%s: revparse %s failed: %d\n", __func__, spec, n);
git_repository_free(git_repo_build_specific);
return SAIB_CHECKOUT_NOT_IN_LOCAL_MIRROR;
}
again:
co_opts.checkout_strategy = GIT_CHECKOUT_FORCE;
n = git_checkout_tree(git_repo_build_specific, treeish, &co_opts);
git_object_free(treeish);
if (n) {
if (n == GIT_EUNBORNBRANCH && tries--) {
lwsl_warn("%s: git checkout says HEAD is empty branch\n",
__func__);
/*
* It's telling us we need to delete the local mirror
* HEAD and retry
*/
lws_snprintf(dp, sizeof(dp), "%s/HEAD", ns->inp);
unlink(dp);
goto again;
}
goto co_failed;
}
lws_snprintf(spec, sizeof(spec), "refs/heads/ref-%s", ns->hash);
git_repository_set_head(git_repo_build_specific, spec);
lwsl_notice("%s: checkout OK\n", __func__);
git_repository_free(git_repo_build_specific);
return SAIB_CHECKOUT_OK;
co_failed:
lwsl_err("%s: git checkout failed: %d\n", __func__, n);
git_repository_free(git_repo_build_specific);
return SAIB_CHECKOUT_CHECKOUT_FAILED;
}
/*
* We are a threadpool thread handling queueing on remote mirror "thread_repo",
* and afterwards checking out a ref from the local copy.
*
* The main git2 process just goes away and does the fetch atomically. Wrapping
* it in an extra threadpool thread lets us continue to be resposive while we're
* waiting for the remote mirror fetch.
*/
enum lws_threadpool_task_return
saib_mirror_task(void *user, enum lws_threadpool_task_status s)
{
struct sai_nspawn *ns = (struct sai_nspawn *)user;
sai_mirror_instance_t *mi;
sai_mirror_req_t *req;
int n, m;
lwsl_warn("%s: entry: state %d\n", __func__, ns->state);
mi = &builder.mi;
if (s == LWS_TP_STATUS_STOPPING)
return LWS_TP_RETURN_STOPPED;
switch (ns->state) {
case NSSTATE_INIT:
case NSSTATE_MOUNTING:
case NSSTATE_STARTING_MIRROR:
lwsl_notice("%s: NSSTATE_STARTING_MIRROR\n", __func__);
ns->state = NSSTATE_CHECKOUT_SPEC;
/* fallthru */
case NSSTATE_CHECKOUT_SPEC:
/*
* First attempt to checkout from local mirror, in case we
* already fetched it to the local mirror for an earlier task
*/
lwsl_notice("%s: NSSTATE_CHECKOUT_SPEC\n", __func__);
switch (sai_mirror_local_checkout(ns)) {
case SAIB_CHECKOUT_OK:
/*
* oh we have it then... do a final sync and have the
* foreground handler STOP us when we resume
*/
lwsl_notice("%s: syncing checkout %s done\n", __func__,
ns->inp);
ns->state = NSSTATE_CHECKEDOUT;
lws_snprintf(ns->pending_mirror_log,
sizeof(ns->pending_mirror_log),
">saib> Local mirror checkout %s\n", ns->hash);
return LWS_TP_RETURN_SYNC;
case SAIB_CHECKOUT_NOT_IN_LOCAL_MIRROR:
/*
* Basically it means we have to get it from the remote
* repo into the local mirror first... clear down the
* local build dir
*/
lws_dir(ns->inp, NULL, lws_dir_rm_rf_cb);
/*
* Make sure the dir itself is left standing in there
*/
if (mkdir(ns->inp, 0755))
lwsl_notice("%s: mkdir %s failed\n", __func__, ns->inp);
/*
* Form a request, kick the remoting thread and then
* wait on the condition in the request
*/
req = malloc(sizeof(*req));
if (!req)
goto fail;
/*
* The request needs to exist with a standalone
* lifetime regardless of what's happening to the ns or
* threadpool thread while it waits, or proceeds
* asynchronously
*/
lwsl_notice("%s: NOT_IN_LOCAL_MIRROR %s\n", __func__, ns->ref);
memset(req, 0, sizeof(*req));
req->state = SRFS_REQUESTING;
req->ns = ns;
lws_strncpy(req->url, ns->git_repo_url, sizeof(req->url));
lws_strncpy(req->hash, ns->hash, sizeof(req->hash));
lws_strncpy(req->ref, ns->ref, sizeof(req->ref));
lws_strncpy(req->path, ns->path, sizeof(req->path));
pthread_mutex_lock(&mi->mut);
lws_dll2_add_tail(&req->list, &mi->pending_req);
pthread_cond_broadcast(&mi->cond);
pthread_mutex_unlock(&mi->mut);
ns->state = NSSTATE_WAIT_REMOTE_MIRROR;
ns->mirror_wait_budget = 600;
lws_snprintf(ns->pending_mirror_log,
sizeof(ns->pending_mirror_log),
">saib> Starting REMOTE MIRROR FETCH\n");
return LWS_TP_RETURN_SYNC;
case SAIB_CHECKOUT_CHECKOUT_FAILED:
lws_snprintf(ns->pending_mirror_log,
sizeof(ns->pending_mirror_log),
">saib> Checkout failed...\n");
goto fail;
}
break;
case NSSTATE_CHECKOUT:
/*
* We come here after the remote -> local mirror operation
* seemed to go well, to complete the flow by checking out
* the newly-fetched commit. We can only go OK or fail.
*/
lwsl_notice("%s: NSSTATE_CHECKOUT\n", __func__);
m = sai_mirror_local_checkout(ns);
lwsl_notice("%s: sai_mirror_local_checkout() says %d\n", __func__, m);
switch (m) {
case SAIB_CHECKOUT_OK:
/*
* oh we have it then... do a final sync and have the
* foreground handler STOP us when we resume
*/
lwsl_notice("%s: syncing checkout %s done\n", __func__,
ns->inp);
ns->state = NSSTATE_CHECKEDOUT;
lws_snprintf(ns->pending_mirror_log,
sizeof(ns->pending_mirror_log),
">saib> Remote->Local->Checked out %s\n", ns->hash);
return LWS_TP_RETURN_SYNC;
case SAIB_CHECKOUT_NOT_IN_LOCAL_MIRROR:
/* fallthru */
lwsl_notice("%s: checkout not it local mirror\n", __func__);
case SAIB_CHECKOUT_CHECKOUT_FAILED:
lws_snprintf(ns->pending_mirror_log,
sizeof(ns->pending_mirror_log),
">saib> Checkout failed after mirror...\n");
lwsl_notice("%s: checkout failed\n", __func__);
goto fail;
}
break;
case NSSTATE_CHECKEDOUT:
case NSSTATE_BUILD:
case NSSTATE_DONE:
case NSSTATE_FAILED:
break;
case NSSTATE_WAIT_REMOTE_MIRROR:
/*
* We are waiting for our request to be handled... we need to
* watch the req completed list at intervals. Anything on the
* completed_req owner has either completed or failed.
*/
lwsl_notice("%s: NSSTATE_WAIT_REMOTE_MIRROR\n", __func__);
pthread_mutex_lock(&mi->mut);
lws_start_foreach_dll_safe(struct lws_dll2 *, d, d1,
mi->completed_req.head) {
sai_mirror_req_t *r = lws_container_of(d,
sai_mirror_req_t, list);
if (r->ns == ns) {
/*
* It's our request that has completed
*/
n = r->state;
lws_dll2_remove(&r->list);
pthread_mutex_unlock(&mi->mut);
free(r);
if (n == SRFS_FAILED) {
lwsl_notice("%s: mirror req failed\n",
__func__);
goto fail;
}
/*
* Leave in NSSTATE_CHECKOUT and come back to
* continue with checking out after we have
* sync'd with comms to server
*/
ns->state = NSSTATE_CHECKOUT;
lws_snprintf(ns->pending_mirror_log,
sizeof(ns->pending_mirror_log),
">saib> Remote -> Local OK\n");
return LWS_TP_RETURN_SYNC;
}
} lws_end_foreach_dll_safe(d, d1);
pthread_mutex_unlock(&mi->mut); /* --- mi->mut unlock */
#if defined(WIN32)
Sleep(1000);
#else
sleep(1);
#endif
if (!--ns->mirror_wait_budget) {
lws_snprintf(ns->pending_mirror_log, sizeof(ns->pending_mirror_log),
">saib> timed out waiting for mirror\n");
lwsl_notice("%s: timed out waiting for mirror\n", __func__);
goto fail;
}
lws_snprintf(ns->pending_mirror_log, sizeof(ns->pending_mirror_log),
">saib> Waiting on MIRROR...\n");
return LWS_TP_RETURN_SYNC;
}
return LWS_TP_RETURN_SYNC;
fail:
/*
* If we have an incomplete request on the mirror thread, remove it
*/
pthread_mutex_lock(&mi->mut);
lws_start_foreach_dll_safe(struct lws_dll2 *, d, d1,
mi->pending_req.head) {
sai_mirror_req_t *r = lws_container_of(d,
sai_mirror_req_t, list);
if (r->ns == ns) {
lws_dll2_remove(&r->list);
free(r);
}
} lws_end_foreach_dll_safe(d, d1);
pthread_mutex_unlock(&mi->mut);
lwsl_err("%s: failed\n", __func__);
ns->retcode = SAISPRF_EXIT | 253;
return LWS_TP_RETURN_SYNC;
}
/*
* This thread serially handles requests for remote mirrors, since there's a
* write lock in the filesystem copy when someone is updating the mirror.
*
* It picks takes queued requests from the head
*/
void *
thread_repo(void *d)
{
sai_mirror_instance_t *mi = (sai_mirror_instance_t *)d;
sai_mirror_req_t *req, rcopy;
int new_state;
int n;
lwsl_notice("%s: repo thread start\n", __func__);
git_libgit2_init();
while (!mi->finish) {
git_fetch_options opts = GIT_FETCH_OPTIONS_INIT;
char spec[96], *paths[] = { spec };
git_strarray rfs = { paths, 1 };
git_repository *repo_mirror;
git_remote *remote;
pthread_mutex_lock(&mi->mut);
/* we sleep if there are no requests pending or ongoing */
while (!mi->pending_req.count && !mi->finish)
pthread_cond_wait(&mi->cond, &mi->mut);
if (mi->finish) {
pthread_mutex_unlock(&mi->mut);
break;
}
/*
* Starting from the head, look for the first request that's in
* a state we should start the remote for it
*/
req = NULL;
lws_start_foreach_dll_safe(struct lws_dll2 *, d, d1,
mi->pending_req.head) {
sai_mirror_req_t *r = lws_container_of(d,
sai_mirror_req_t, list);
if (r->state == SRFS_REQUESTING) {
req = r;
lwsl_notice("%s: setting processing\n",
__func__);
sai_mirror_req_state_set(req, SRFS_PROCESSING);
break;
}
} lws_end_foreach_dll_safe(d, d1);
//req = lws_dll2_get_head(&bi->requests);
//lws_dll2_remove(&->overall_list);
/*
* The request object on the list might be removed and destroyed
* while we do this long-term mirroring action. So take a temp
* copy of it to set the action up, before releasing the mutex.
*/
if (req)
rcopy = *req;
pthread_mutex_unlock(&mi->mut);
if (!req)
continue;
/*
* ... we cannot dereference req after releasing the mutex.
* We made a temp copy of it in rcopy, to set the transaction
* up we can use that so we can be sure it's around for that.
*/
/*
* git init --bare <path>
*/
new_state = SRFS_FAILED;
repo_mirror = NULL;
if (git_repository_init(&repo_mirror, rcopy.path, 1)) {
fprintf(stderr, "%s: unable to init sticky repo %s, errno %d\n",
__func__, rcopy.path, errno);
goto fail_out;
}
/*
* Fetch over the branch or tag we're interested in from the
* remote repo and into our local sticky mirror
*
* git fetch <remote repo> +<ref>:<ref>
*/
if (git_remote_create_anonymous(&remote, repo_mirror, rcopy.url)) {
fprintf(stderr, "%s: cant find remote %s\n", __func__,
rcopy.url);
git_repository_free(repo_mirror);
goto fail_out;
}
lws_snprintf(spec, sizeof(spec), "%s:ref-%s", rcopy.ref, rcopy.hash);
fprintf(stderr, "%s: fetching %s %s\n", __func__, rcopy.url, spec);
/*
* This may take an open-ended amount of time
*/
n = git_remote_fetch(remote, &rfs, &opts, "fetch");
git_remote_free(remote);
git_repository_free(repo_mirror);
if (n) {
#if defined(SAI_HAVE_LIBGIT2_GIT_ERROR)
const git_error *e = git_error_last();
if (e)
fprintf(stderr, "%s: git error %s\n", __func__,
e->message);
#endif
fprintf(stderr, "%s: failed to fetch %s, n: %d\n",
__func__, spec, n);
goto fail_out;
}
fprintf(stderr, "%s: syncing mirror fetch %s %s successful\n",
__func__, rcopy.url, rcopy.hash);
new_state = SRFS_SUCCEEDED;
fail_out:
/*
* We notify the threadpool monitoring thread
*/
pthread_mutex_lock(&mi->mut);
/*
* The requestor and its request may have gone. And, it's
* possible we got several queued requests that were actually
* waiting for the same mirror transaction which has now
* succeeded or failed the same for all of them.
*
* Let's take the approach to lock the queue and tell everybody
* at once who's asking for the same thing what the outcome was.
*/
lws_start_foreach_dll_safe(struct lws_dll2 *, d, d1,
mi->pending_req.head) {
sai_mirror_req_t *r = lws_container_of(d,
sai_mirror_req_t, list);
if ((r->state == SRFS_REQUESTING ||
r->state == SRFS_PROCESSING) &&
!strcmp(r->url, rcopy.url) &&
!strcmp(r->hash, rcopy.hash) &&
!strcmp(r->path, rcopy.path) &&
!strcmp(r->ref, rcopy.ref)) {
/*
* Change the state of matching guys and put
* them on to the completed_req list owner
*/
fprintf(stderr, "%s: setting req state %d\n",
__func__, new_state);
sai_mirror_req_state_set(r, new_state);
lws_dll2_remove(&r->list);
lws_dll2_add_tail(&r->list, &mi->completed_req);
}
} lws_end_foreach_dll_safe(d, d1);
pthread_mutex_unlock(&mi->mut);
}
lwsl_notice("%s: repo thread exiting\n", __func__);
git_libgit2_shutdown();
pthread_exit(NULL);
return NULL;
}
|