/*
* Copyright (C) Igor Sysoev
* Copyright (C) Nginx, Inc.
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>
#include <ngx_md5.h>
static ngx_int_t ngx_http_file_cache_lock(ngx_http_request_t *r,
ngx_http_cache_t *c);
static void ngx_http_file_cache_lock_wait_handler(ngx_event_t *ev);
static ngx_int_t ngx_http_file_cache_read(ngx_http_request_t *r,
ngx_http_cache_t *c);
static ssize_t ngx_http_file_cache_aio_read(ngx_http_request_t *r,
ngx_http_cache_t *c);
#if (NGX_HAVE_FILE_AIO)
static void ngx_http_cache_aio_event_handler(ngx_event_t *ev);
#endif
static ngx_int_t ngx_http_file_cache_exists(ngx_http_file_cache_t *cache,
ngx_http_cache_t *c);
static ngx_int_t ngx_http_file_cache_name(ngx_http_request_t *r,
ngx_path_t *path);
static ngx_http_file_cache_node_t *
ngx_http_file_cache_lookup(ngx_http_file_cache_t *cache, u_char *key);
static void ngx_http_file_cache_rbtree_insert_value(ngx_rbtree_node_t *temp,
ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel);
static void ngx_http_file_cache_cleanup(void *data);
static time_t ngx_http_file_cache_forced_expire(ngx_http_file_cache_t *cache);
static time_t ngx_http_file_cache_expire(ngx_http_file_cache_t *cache);
static void ngx_http_file_cache_delete(ngx_http_file_cache_t *cache,
ngx_queue_t *q, u_char *name);
static void ngx_http_file_cache_loader_sleep(ngx_http_file_cache_t *cache);
static ngx_int_t ngx_http_file_cache_noop(ngx_tree_ctx_t *ctx,
ngx_str_t *path);
static ngx_int_t ngx_http_file_cache_manage_file(ngx_tree_ctx_t *ctx,
ngx_str_t *path);
static ngx_int_t ngx_http_file_cache_add_file(ngx_tree_ctx_t *ctx,
ngx_str_t *path);
static ngx_int_t ngx_http_file_cache_add(ngx_http_file_cache_t *cache,
ngx_http_cache_t *c);
static ngx_int_t ngx_http_file_cache_delete_file(ngx_tree_ctx_t *ctx,
ngx_str_t *path);
ngx_str_t ngx_http_cache_status[] = {
ngx_string("MISS"),
ngx_string("BYPASS"),
ngx_string("EXPIRED"),
ngx_string("STALE"),
ngx_string("UPDATING"),
ngx_string("HIT")
};
static u_char ngx_http_file_cache_key[] = { LF, 'K', 'E', 'Y', ':', ' ' };
static ngx_int_t
ngx_http_file_cache_init(ngx_shm_zone_t *shm_zone, void *data)
{
ngx_http_file_cache_t *ocache = data;
size_t len;
ngx_uint_t n;
ngx_http_file_cache_t *cache;
cache = shm_zone->data;
if (ocache) {
if (ngx_strcmp(cache->path->name.data, ocache->path->name.data) != 0) {
ngx_log_error(NGX_LOG_EMERG, shm_zone->shm.log, 0,
"cache \"%V\" uses the \"%V\" cache path "
"while previously it used the \"%V\" cache path",
&shm_zone->shm.name, &cache->path->name,
&ocache->path->name);
return NGX_ERROR;
}
for (n = 0; n < 3; n++) {
if (cache->path->level[n] != ocache->path->level[n]) {
ngx_log_error(NGX_LOG_EMERG, shm_zone->shm.log, 0,
"cache \"%V\" had previously different levels",
&shm_zone->shm.name);
return NGX_ERROR;
}
}
cache->sh = ocache->sh;
cache->shpool = ocache->shpool;
cache->bsize = ocache->bsize;
cache->max_size /= cache->bsize;
if (!cache->sh->cold || cache->sh->loading) {
cache->path->loader = NULL;
}
return NGX_OK;
}
cache->shpool = (ngx_slab_pool_t *) shm_zone->shm.addr;
if (shm_zone->shm.exists) {
cache->sh = cache->shpool->data;
cache->bsize = ngx_fs_bsize(cache->path->name.data);
return NGX_OK;
}
cache->sh = ngx_slab_alloc(cache->shpool, sizeof(ngx_http_file_cache_sh_t));
if (cache->sh == NULL) {
return NGX_ERROR;
}
cache->shpool->data = cache->sh;
ngx_rbtree_init(&cache->sh->rbtree, &cache->sh->sentinel,
ngx_http_file_cache_rbtree_insert_value);
ngx_queue_init(&cache->sh->queue);
cache->sh->cold = 1;
cache->sh->loading = 0;
cache->sh->size = 0;
cache->bsize = ngx_fs_bsize(cache->path->name.data);
cache->max_size /= cache->bsize;
len = sizeof(" in cache keys zone \"\"") + shm_zone->shm.name.len;
cache->shpool->log_ctx = ngx_slab_alloc(cache->shpool, len);
if (cache->shpool->log_ctx == NULL) {
return NGX_ERROR;
}
ngx_sprintf(cache->shpool->log_ctx, " in cache keys zone \"%V\"%Z",
&shm_zone->shm.name);
return NGX_OK;
}
ngx_int_t
ngx_http_file_cache_new(ngx_http_request_t *r)
{
ngx_http_cache_t *c;
c = ngx_pcalloc(r->pool, sizeof(ngx_http_cache_t));
if (c == NULL) {
return NGX_ERROR;
}
if (ngx_array_init(&c->keys, r->pool, 4, sizeof(ngx_str_t)) != NGX_OK) {
return NGX_ERROR;
}
r->cache = c;
c->file.log = r->connection->log;
c->file.fd = NGX_INVALID_FILE;
return NGX_OK;
}
ngx_int_t
ngx_http_file_cache_create(ngx_http_request_t *r)
{
ngx_http_cache_t *c;
ngx_pool_cleanup_t *cln;
ngx_http_file_cache_t *cache;
c = r->cache;
cache = c->file_cache;
cln = ngx_pool_cleanup_add(r->pool, 0);
if (cln == NULL) {
return NGX_ERROR;
}
cln->handler = ngx_http_file_cache_cleanup;
cln->data = c;
if (ngx_http_file_cache_exists(cache, c) == NGX_ERROR) {
return NGX_ERROR;
}
if (ngx_http_file_cache_name(r, cache->path) != NGX_OK) {
return NGX_ERROR;
}
return NGX_OK;
}
void
ngx_http_file_cache_create_key(ngx_http_request_t *r)
{
size_t len;
ngx_str_t *key;
ngx_uint_t i;
ngx_md5_t md5;
ngx_http_cache_t *c;
c = r->cache;
len = 0;
ngx_crc32_init(c->crc32);
ngx_md5_init(&md5);
key = c->keys.elts;
for (i = 0; i < c->keys.nelts; i++) {
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"http cache key: \"%V\"", &key[i]);
len += key[i].len;
ngx_crc32_update(&c->crc32, key[i].data, key[i].len);
ngx_md5_update(&md5, key[i].data, key[i].len);
}
c->header_start = sizeof(ngx_http_file_cache_header_t)
+ sizeof(ngx_http_file_cache_key) + len + 1;
ngx_crc32_final(c->crc32);
ngx_md5_final(c->key, &md5);
}
ngx_int_t
ngx_http_file_cache_open(ngx_http_request_t *r)
{
ngx_int_t rc, rv;
ngx_uint_t cold, test;
ngx_http_cache_t *c;
ngx_pool_cleanup_t *cln;
ngx_open_file_info_t of;
ngx_http_file_cache_t *cache;
ngx_http_core_loc_conf_t *clcf;
c = r->cache;
if (c->waiting) {
return NGX_AGAIN;
}
if (c->buf) {
return ngx_http_file_cache_read(r, c);
}
cache = c->file_cache;
if (c->node == NULL) {
cln = ngx_pool_cleanup_add(r->pool, 0);
if (cln == NULL) {
return NGX_ERROR;
}
cln->handler = ngx_http_file_cache_cleanup;
cln->data = c;
}
rc = ngx_http_file_cache_exists(cache, c);
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"http file cache exists: %i e:%d", rc, c->exists);
if (rc == NGX_ERROR) {
return rc;
}
if (rc == NGX_AGAIN) {
return NGX_HTTP_CACHE_SCARCE;
}
cold = cache->sh->cold;
if (rc == NGX_OK) {
if (c->error) {
return c->error;
}
c->temp_file = 1;
test = c->exists ? 1 : 0;
rv = NGX_DECLINED;
} else { /* rc == NGX_DECLINED */
if (c->min_uses > 1) {
if (!cold) {
return NGX_HTTP_CACHE_SCARCE;
}
test = 1;
rv = NGX_HTTP_CACHE_SCARCE;
} else {
c->temp_file = 1;
test = cold ? 1 : 0;
rv = NGX_DECLINED;
}
}
if (ngx_http_file_cache_name(r, cache->path) != NGX_OK) {
return NGX_ERROR;
}
if (!test) {
goto done;
}
clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
ngx_memzero(&of, sizeof(ngx_open_file_info_t));
of.uniq = c->uniq;
of.valid = clcf->open_file_cache_valid;
of.min_uses = clcf->open_file_cache_min_uses;
of.events = clcf->open_file_cache_events;
of.directio = NGX_OPEN_FILE_DIRECTIO_OFF;
of.read_ahead = clcf->read_ahead;
if (ngx_open_cached_file(clcf->open_file_cache, &c->file.name, &of, r->pool)
!= NGX_OK)
{
switch (of.err) {
case 0:
return NGX_ERROR;
case NGX_ENOENT:
case NGX_ENOTDIR:
goto done;
default:
ngx_log_error(NGX_LOG_CRIT, r->connection->log, of.err,
ngx_open_file_n " \"%s\" failed", c->file.name.data);
return NGX_ERROR;
}
}
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"http file cache fd: %d", of.fd);
c->file.fd = of.fd;
c->file.log = r->connection->log;
c->uniq = of.uniq;
c->length = of.size;
c->fs_size = (of.fs_size + cache->bsize - 1) / cache->bsize;
c->buf = ngx_create_temp_buf(r->pool, c->body_start);
if (c->buf == NULL) {
return NGX_ERROR;
}
return ngx_http_file_cache_read(r, c);
done:
if (rv == NGX_DECLINED) {
return ngx_http_file_cache_lock(r, c);
}
return rv;
}
static ngx_int_t
ngx_http_file_cache_lock(ngx_http_request_t *r, ngx_http_cache_t *c)
{
ngx_msec_t now, timer;
ngx_http_file_cache_t *cache;
if (!c->lock) {
return NGX_DECLINED;
}
cache = c->file_cache;
ngx_shmtx_lock(&cache->shpool->mutex);
if (!c->node->updating) {
c->node->updating = 1;
c->updating = 1;
}
ngx_shmtx_unlock(&cache->shpool->mutex);
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"http file cache lock u:%d wt:%M",
c->updating, c->wait_time);
if (c->updating) {
return NGX_DECLINED;
}
c->waiting = 1;
now = ngx_current_msec;
if (c->wait_time == 0) {
c->wait_time = now + c->lock_timeout;
c->wait_event.handler = ngx_http_file_cache_lock_wait_handler;
c->wait_event.data = r;
c->wait_event.log = r->connection->log;
}
timer = c->wait_time - now;
ngx_add_timer(&c->wait_event, (timer > 500) ? 500 : timer);
r->main->blocked++;
return NGX_AGAIN;
}
static void
ngx_http_file_cache_lock_wait_handler(ngx_event_t *ev)
{
ngx_uint_t wait;
ngx_msec_t timer;
ngx_http_cache_t *c;
ngx_http_request_t *r;
ngx_http_file_cache_t *cache;
r = ev->data;
c = r->cache;
ngx_log_debug2(NGX_LOG_DEBUG_HTTP, ev->log, 0,
"http file cache wait handler wt:%M cur:%M",
c->wait_time, ngx_current_msec);
timer = c->wait_time - ngx_current_msec;
if ((ngx_msec_int_t) timer <= 0) {
ngx_log_error(NGX_LOG_INFO, ev->log, 0, "cache lock timeout");
c->lock = 0;
goto wakeup;
}
cache = c->file_cache;
wait = 0;
ngx_shmtx_lock(&cache->shpool->mutex);
if (c->node->updating) {
wait = 1;
}
ngx_shmtx_unlock(&cache->shpool->mutex);
if (wait) {
ngx_add_timer(ev, (timer > 500) ? 500 : timer);
return;
}
wakeup:
c->waiting = 0;
r->main->blocked--;
r->connection->write->handler(r->connection->write);
}
static ngx_int_t
ngx_http_file_cache_read(ngx_http_request_t *r, ngx_http_cache_t *c)
{
time_t now;
ssize_t n;
ngx_int_t rc;
ngx_http_file_cache_t *cache;
ngx_http_file_cache_header_t *h;
n = ngx_http_file_cache_aio_read(r, c);
if (n < 0) {
return n;
}
if ((size_t) n < c->header_start) {
ngx_log_error(NGX_LOG_CRIT, r->connection->log, 0,
"cache file \"%s\" is too small", c->file.name.data);
return NGX_DECLINED;
}
h = (ngx_http_file_cache_header_t *) c->buf->pos;
if (h->crc32 != c->crc32) {
ngx_log_error(NGX_LOG_CRIT, r->connection->log, 0,
"cache file \"%s\" has md5 collision", c->file.name.data);
return NGX_DECLINED;
}
if (h->body_start > c->body_start) {
ngx_log_error(NGX_LOG_CRIT, r->connection->log, 0,
"cache file \"%s\" has too long header",
c->file.name.data);
return NGX_DECLINED;
}
c->buf->last += n;
c->valid_sec = h->valid_sec;
c->last_modified = h->last_modified;
c->date = h->date;
c->valid_msec = h->valid_msec;
c->header_start = h->header_start;
c->body_start = h->body_start;
r->cached = 1;
cache = c->file_cache;
if (cache->sh->cold) {
ngx_shmtx_lock(&cache->shpool->mutex);
if (!c->node->exists) {
c->node->uses = 1;
c->node->body_start = c->body_start;
c->node->exists = 1;
c->node->uniq = c->uniq;
c->node->fs_size = c->fs_size;
cache->sh->size += c->fs_size;
}
ngx_shmtx_unlock(&cache->shpool->mutex);
}
now = ngx_time();
if (c->valid_sec < now) {
ngx_shmtx_lock(&cache->shpool->mutex);
if (c->node->updating) {
rc = NGX_HTTP_CACHE_UPDATING;
} else {
c->node->updating = 1;
c->updating = 1;
rc = NGX_HTTP_CACHE_STALE;
}
ngx_shmtx_unlock(&cache->shpool->mutex);
ngx_log_debug3(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"http file cache expired: %i %T %T",
rc, c->valid_sec, now);
return rc;
}
return NGX_OK;
}
static ssize_t
ngx_http_file_cache_aio_read(ngx_http_request_t *r, ngx_http_cache_t *c)
{
#if (NGX_HAVE_FILE_AIO)
ssize_t n;
ngx_http_core_loc_conf_t *clcf;
if (!ngx_file_aio) {
goto noaio;
}
clcf = ngx_http_get_module_loc_conf(r, ngx_http_core_module);
if (!clcf->aio) {
goto noaio;
}
n = ngx_file_aio_read(&c->file, c->buf->pos, c->body_start, 0, r->pool);
if (n != NGX_AGAIN) {
return n;
}
c->file.aio->data = r;
c->file.aio->handler = ngx_http_cache_aio_event_handler;
r->main->blocked++;
r->aio = 1;
return NGX_AGAIN;
noaio:
#endif
return ngx_read_file(&c->file, c->buf->pos, c->body_start, 0);
}
#if (NGX_HAVE_FILE_AIO)
static void
ngx_http_cache_aio_event_handler(ngx_event_t *ev)
{
ngx_event_aio_t *aio;
ngx_http_request_t *r;
aio = ev->data;
r = aio->data;
r->main->blocked--;
r->aio = 0;
r->connection->write->handler(r->connection->write);
}
#endif
static ngx_int_t
ngx_http_file_cache_exists(ngx_http_file_cache_t *cache, ngx_http_cache_t *c)
{
ngx_int_t rc;
ngx_http_file_cache_node_t *fcn;
ngx_shmtx_lock(&cache->shpool->mutex);
fcn = c->node;
if (fcn == NULL) {
fcn = ngx_http_file_cache_lookup(cache, c->key);
}
if (fcn) {
ngx_queue_remove(&fcn->queue);
if (c->node == NULL) {
fcn->uses++;
fcn->count++;
}
if (fcn->error) {
if (fcn->valid_sec < ngx_time()) {
goto renew;
}
rc = NGX_OK;
goto done;
}
if (fcn->exists || fcn->uses >= c->min_uses) {
c->exists = fcn->exists;
if (fcn->body_start) {
c->body_start = fcn->body_start;
}
rc = NGX_OK;
goto done;
}
rc = NGX_AGAIN;
goto done;
}
fcn = ngx_slab_alloc_locked(cache->shpool,
sizeof(ngx_http_file_cache_node_t));
if (fcn == NULL) {
ngx_shmtx_unlock(&cache->shpool->mutex);
(void) ngx_http_file_cache_forced_expire(cache);
ngx_shmtx_lock(&cache->shpool->mutex);
fcn = ngx_slab_alloc_locked(cache->shpool,
sizeof(ngx_http_file_cache_node_t));
if (fcn == NULL) {
rc = NGX_ERROR;
goto failed;
}
}
ngx_memcpy((u_char *) &fcn->node.key, c->key, sizeof(ngx_rbtree_key_t));
ngx_memcpy(fcn->key, &c->key[sizeof(ngx_rbtree_key_t)],
NGX_HTTP_CACHE_KEY_LEN - sizeof(ngx_rbtree_key_t));
ngx_rbtree_insert(&cache->sh->rbtree, &fcn->node);
fcn->uses = 1;
fcn->count = 1;
fcn->updating = 0;
fcn->deleting = 0;
renew:
rc = NGX_DECLINED;
fcn->valid_msec = 0;
fcn->error = 0;
fcn->exists = 0;
fcn->valid_sec = 0;
fcn->uniq = 0;
fcn->body_start = 0;
fcn->fs_size = 0;
done:
fcn->expire = ngx_time() + cache->inactive;
ngx_queue_insert_head(&cache->sh->queue, &fcn->queue);
c->uniq = fcn->uniq;
c->error = fcn->error;
c->node = fcn;
failed:
ngx_shmtx_unlock(&cache->shpool->mutex);
return rc;
}
static ngx_int_t
ngx_http_file_cache_name(ngx_http_request_t *r, ngx_path_t *path)
{
u_char *p;
ngx_http_cache_t *c;
c = r->cache;
if (c->file.name.len) {
return NGX_OK;
}
c->file.name.len = path->name.len + 1 + path->len
+ 2 * NGX_HTTP_CACHE_KEY_LEN;
c->file.name.data = ngx_pnalloc(r->pool, c->file.name.len + 1);
if (c->file.name.data == NULL) {
return NGX_ERROR;
}
ngx_memcpy(c->file.name.data, path->name.data, path->name.len);
p = c->file.name.data + path->name.len + 1 + path->len;
p = ngx_hex_dump(p, c->key, NGX_HTTP_CACHE_KEY_LEN);
*p = '\0';
ngx_create_hashed_filename(path, c->file.name.data, c->file.name.len);
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"cache file: \"%s\"", c->file.name.data);
return NGX_OK;
}
static ngx_http_file_cache_node_t *
ngx_http_file_cache_lookup(ngx_http_file_cache_t *cache, u_char *key)
{
ngx_int_t rc;
ngx_rbtree_key_t node_key;
ngx_rbtree_node_t *node, *sentinel;
ngx_http_file_cache_node_t *fcn;
ngx_memcpy((u_char *) &node_key, key, sizeof(ngx_rbtree_key_t));
node = cache->sh->rbtree.root;
sentinel = cache->sh->rbtree.sentinel;
while (node != sentinel) {
if (node_key < node->key) {
node = node->left;
continue;
}
if (node_key > node->key) {
node = node->right;
continue;
}
/* node_key == node->key */
fcn = (ngx_http_file_cache_node_t *) node;
rc = ngx_memcmp(&key[sizeof(ngx_rbtree_key_t)], fcn->key,
NGX_HTTP_CACHE_KEY_LEN - sizeof(ngx_rbtree_key_t));
if (rc == 0) {
return fcn;
}
node = (rc < 0) ? node->left : node->right;
}
/* not found */
return NULL;
}
static void
ngx_http_file_cache_rbtree_insert_value(ngx_rbtree_node_t *temp,
ngx_rbtree_node_t *node, ngx_rbtree_node_t *sentinel)
{
ngx_rbtree_node_t **p;
ngx_http_file_cache_node_t *cn, *cnt;
for ( ;; ) {
if (node->key < temp->key) {
p = &temp->left;
} else if (node->key > temp->key) {
p = &temp->right;
} else { /* node->key == temp->key */
cn = (ngx_http_file_cache_node_t *) node;
cnt = (ngx_http_file_cache_node_t *) temp;
p = (ngx_memcmp(cn->key, cnt->key,
NGX_HTTP_CACHE_KEY_LEN - sizeof(ngx_rbtree_key_t))
< 0)
? &temp->left : &temp->right;
}
if (*p == sentinel) {
break;
}
temp = *p;
}
*p = node;
node->parent = temp;
node->left = sentinel;
node->right = sentinel;
ngx_rbt_red(node);
}
void
ngx_http_file_cache_set_header(ngx_http_request_t *r, u_char *buf)
{
ngx_http_file_cache_header_t *h = (ngx_http_file_cache_header_t *) buf;
u_char *p;
ngx_str_t *key;
ngx_uint_t i;
ngx_http_cache_t *c;
ngx_log_debug0(NGX_LOG_DEBUG_HTTP, r->connection->log, 0,
"http file cache set header");
c = r->cache;
ngx_memzero(h, sizeof(ngx_http_file_cache_header_t));
h->valid_sec = c->valid_sec;
h->last_modified = c->last_modified;
h->date = c->date;
h->crc32 = c->crc32;
h->valid_msec = (u_short) c->valid_msec;
h->header_start = (u_short) c->header_start;
h->body_start = (u_short) c->body_start;
p = buf + sizeof(ngx_http_file_cache_header_t);
p = ngx_cpymem(p, ngx_http_file_cache_key, sizeof(ngx_http_file_cache_key));
key = c->keys.elts;
for (i = 0; i < c->keys.nelts; i++) {
p = ngx_copy(p, key[i].data, key[i].len);
}
*p = LF;
}
void
ngx_http_file_cache_update(ngx_http_request_t *r, ngx_temp_file_t *tf)
{
off_t fs_size;
ngx_int_t rc;
ngx_file_uniq_t uniq;
ngx_file_info_t fi;
ngx_http_cache_t *c;
ngx_ext_rename_file_t ext;
ngx_http_file_cache_t *cache;
<