diff options
Diffstat (limited to 'Utilities/cmcurl/lib/conncache.c')
| -rw-r--r-- | Utilities/cmcurl/lib/conncache.c | 641 |
1 files changed, 641 insertions, 0 deletions
diff --git a/Utilities/cmcurl/lib/conncache.c b/Utilities/cmcurl/lib/conncache.c new file mode 100644 index 0000000..b8f5444 --- /dev/null +++ b/Utilities/cmcurl/lib/conncache.c @@ -0,0 +1,641 @@ +/*************************************************************************** + * _ _ ____ _ + * Project ___| | | | _ \| | + * / __| | | | |_) | | + * | (__| |_| | _ <| |___ + * \___|\___/|_| \_\_____| + * + * Copyright (C) 2012 - 2016, Linus Nielsen Feltzing, <linus@haxx.se> + * Copyright (C) 2012 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al. + * + * This software is licensed as described in the file COPYING, which + * you should have received as part of this distribution. The terms + * are also available at https://curl.haxx.se/docs/copyright.html. + * + * You may opt to use, copy, modify, merge, publish, distribute and/or sell + * copies of the Software, and permit persons to whom the Software is + * furnished to do so, under the terms of the COPYING file. + * + * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY + * KIND, either express or implied. + * + ***************************************************************************/ + +#include "curl_setup.h" + +#include <curl/curl.h> + +#include "urldata.h" +#include "url.h" +#include "progress.h" +#include "multiif.h" +#include "sendf.h" +#include "conncache.h" +#include "share.h" +#include "sigpipe.h" +#include "connect.h" + +/* The last 3 #include files should be in this order */ +#include "curl_printf.h" +#include "curl_memory.h" +#include "memdebug.h" + +#ifdef CURLDEBUG +/* the debug versions of these macros make extra certain that the lock is + never doubly locked or unlocked */ +#define CONN_LOCK(x) if((x)->share) { \ + Curl_share_lock((x), CURL_LOCK_DATA_CONNECT, CURL_LOCK_ACCESS_SINGLE); \ + DEBUGASSERT(!(x)->state.conncache_lock); \ + (x)->state.conncache_lock = TRUE; \ + } + +#define CONN_UNLOCK(x) if((x)->share) { \ + DEBUGASSERT((x)->state.conncache_lock); \ + (x)->state.conncache_lock = FALSE; \ + Curl_share_unlock((x), CURL_LOCK_DATA_CONNECT); \ + } +#else +#define CONN_LOCK(x) if((x)->share) \ + Curl_share_lock((x), CURL_LOCK_DATA_CONNECT, CURL_LOCK_ACCESS_SINGLE) +#define CONN_UNLOCK(x) if((x)->share) \ + Curl_share_unlock((x), CURL_LOCK_DATA_CONNECT) +#endif + +static void conn_llist_dtor(void *user, void *element) +{ + struct connectdata *data = element; + (void)user; + + data->bundle = NULL; +} + +static CURLcode bundle_create(struct Curl_easy *data, + struct connectbundle **cb_ptr) +{ + (void)data; + DEBUGASSERT(*cb_ptr == NULL); + *cb_ptr = malloc(sizeof(struct connectbundle)); + if(!*cb_ptr) + return CURLE_OUT_OF_MEMORY; + + (*cb_ptr)->num_connections = 0; + (*cb_ptr)->multiuse = BUNDLE_UNKNOWN; + + Curl_llist_init(&(*cb_ptr)->conn_list, (curl_llist_dtor) conn_llist_dtor); + return CURLE_OK; +} + +static void bundle_destroy(struct connectbundle *cb_ptr) +{ + if(!cb_ptr) + return; + + Curl_llist_destroy(&cb_ptr->conn_list, NULL); + + free(cb_ptr); +} + +/* Add a connection to a bundle */ +static CURLcode bundle_add_conn(struct connectbundle *cb_ptr, + struct connectdata *conn) +{ + Curl_llist_insert_next(&cb_ptr->conn_list, cb_ptr->conn_list.tail, conn, + &conn->bundle_node); + conn->bundle = cb_ptr; + cb_ptr->num_connections++; + return CURLE_OK; +} + +/* Remove a connection from a bundle */ +static int bundle_remove_conn(struct connectbundle *cb_ptr, + struct connectdata *conn) +{ + struct curl_llist_element *curr; + + curr = cb_ptr->conn_list.head; + while(curr) { + if(curr->ptr == conn) { + Curl_llist_remove(&cb_ptr->conn_list, curr, NULL); + cb_ptr->num_connections--; + conn->bundle = NULL; + return 1; /* we removed a handle */ + } + curr = curr->next; + } + return 0; +} + +static void free_bundle_hash_entry(void *freethis) +{ + struct connectbundle *b = (struct connectbundle *) freethis; + + bundle_destroy(b); +} + +int Curl_conncache_init(struct conncache *connc, int size) +{ + int rc; + + /* allocate a new easy handle to use when closing cached connections */ + connc->closure_handle = curl_easy_init(); + if(!connc->closure_handle) + return 1; /* bad */ + + rc = Curl_hash_init(&connc->hash, size, Curl_hash_str, + Curl_str_key_compare, free_bundle_hash_entry); + if(rc) { + Curl_close(connc->closure_handle); + connc->closure_handle = NULL; + } + else + connc->closure_handle->state.conn_cache = connc; + + return rc; +} + +void Curl_conncache_destroy(struct conncache *connc) +{ + if(connc) + Curl_hash_destroy(&connc->hash); +} + +/* creates a key to find a bundle for this connection */ +static void hashkey(struct connectdata *conn, char *buf, + size_t len) /* something like 128 is fine */ +{ + const char *hostname; + + if(conn->bits.socksproxy) + hostname = conn->socks_proxy.host.name; + else if(conn->bits.httpproxy) + hostname = conn->http_proxy.host.name; + else if(conn->bits.conn_to_host) + hostname = conn->conn_to_host.name; + else + hostname = conn->host.name; + + DEBUGASSERT(len > 32); + + /* put the number first so that the hostname gets cut off if too long */ + snprintf(buf, len, "%ld%s", conn->port, hostname); +} + +void Curl_conncache_unlock(struct connectdata *conn) +{ + CONN_UNLOCK(conn->data); +} + +/* Returns number of connections currently held in the connection cache. + Locks/unlocks the cache itself! +*/ +size_t Curl_conncache_size(struct Curl_easy *data) +{ + size_t num; + CONN_LOCK(data); + num = data->state.conn_cache->num_conn; + CONN_UNLOCK(data); + return num; +} + +/* Returns number of connections currently held in the connections's bundle + Locks/unlocks the cache itself! +*/ +size_t Curl_conncache_bundle_size(struct connectdata *conn) +{ + size_t num; + CONN_LOCK(conn->data); + num = conn->bundle->num_connections; + CONN_UNLOCK(conn->data); + return num; +} + +/* Look up the bundle with all the connections to the same host this + connectdata struct is setup to use. + + **NOTE**: When it returns, it holds the connection cache lock! */ +struct connectbundle *Curl_conncache_find_bundle(struct connectdata *conn, + struct conncache *connc) +{ + struct connectbundle *bundle = NULL; + CONN_LOCK(conn->data); + if(connc) { + char key[128]; + hashkey(conn, key, sizeof(key)); + bundle = Curl_hash_pick(&connc->hash, key, strlen(key)); + } + + return bundle; +} + +static bool conncache_add_bundle(struct conncache *connc, + char *key, + struct connectbundle *bundle) +{ + void *p = Curl_hash_add(&connc->hash, key, strlen(key), bundle); + + return p?TRUE:FALSE; +} + +static void conncache_remove_bundle(struct conncache *connc, + struct connectbundle *bundle) +{ + struct curl_hash_iterator iter; + struct curl_hash_element *he; + + if(!connc) + return; + + Curl_hash_start_iterate(&connc->hash, &iter); + + he = Curl_hash_next_element(&iter); + while(he) { + if(he->ptr == bundle) { + /* The bundle is destroyed by the hash destructor function, + free_bundle_hash_entry() */ + Curl_hash_delete(&connc->hash, he->key, he->key_len); + return; + } + + he = Curl_hash_next_element(&iter); + } +} + +CURLcode Curl_conncache_add_conn(struct conncache *connc, + struct connectdata *conn) +{ + CURLcode result; + struct connectbundle *bundle; + struct connectbundle *new_bundle = NULL; + struct Curl_easy *data = conn->data; + + /* *find_bundle() locks the connection cache */ + bundle = Curl_conncache_find_bundle(conn, data->state.conn_cache); + if(!bundle) { + int rc; + char key[128]; + + result = bundle_create(data, &new_bundle); + if(result) { + goto unlock; + } + + hashkey(conn, key, sizeof(key)); + rc = conncache_add_bundle(data->state.conn_cache, key, new_bundle); + + if(!rc) { + bundle_destroy(new_bundle); + result = CURLE_OUT_OF_MEMORY; + goto unlock; + } + bundle = new_bundle; + } + + result = bundle_add_conn(bundle, conn); + if(result) { + if(new_bundle) + conncache_remove_bundle(data->state.conn_cache, new_bundle); + goto unlock; + } + + conn->connection_id = connc->next_connection_id++; + connc->num_conn++; + + DEBUGF(infof(conn->data, "Added connection %ld. " + "The cache now contains %" CURL_FORMAT_CURL_OFF_TU " members\n", + conn->connection_id, (curl_off_t) connc->num_conn)); + + unlock: + CONN_UNLOCK(data); + + return result; +} + +void Curl_conncache_remove_conn(struct connectdata *conn, bool lock) +{ + struct Curl_easy *data = conn->data; + struct connectbundle *bundle = conn->bundle; + struct conncache *connc = data->state.conn_cache; + + /* The bundle pointer can be NULL, since this function can be called + due to a failed connection attempt, before being added to a bundle */ + if(bundle) { + if(lock) { + CONN_LOCK(conn->data); + } + bundle_remove_conn(bundle, conn); + if(bundle->num_connections == 0) + conncache_remove_bundle(connc, bundle); + conn->bundle = NULL; /* removed from it */ + if(connc) { + connc->num_conn--; + DEBUGF(infof(conn->data, "The cache now contains %" + CURL_FORMAT_CURL_OFF_TU " members\n", + (curl_off_t) connc->num_conn)); + } + if(lock) { + CONN_UNLOCK(conn->data); + } + } +} + +/* This function iterates the entire connection cache and calls the function + func() with the connection pointer as the first argument and the supplied + 'param' argument as the other. + + The conncache lock is still held when the callback is called. It needs it, + so that it can safely continue traversing the lists once the callback + returns. + + Returns 1 if the loop was aborted due to the callback's return code. + + Return 0 from func() to continue the loop, return 1 to abort it. + */ +bool Curl_conncache_foreach(struct Curl_easy *data, + struct conncache *connc, + void *param, + int (*func)(struct connectdata *conn, void *param)) +{ + struct curl_hash_iterator iter; + struct curl_llist_element *curr; + struct curl_hash_element *he; + + if(!connc) + return FALSE; + + CONN_LOCK(data); + Curl_hash_start_iterate(&connc->hash, &iter); + + he = Curl_hash_next_element(&iter); + while(he) { + struct connectbundle *bundle; + + bundle = he->ptr; + he = Curl_hash_next_element(&iter); + + curr = bundle->conn_list.head; + while(curr) { + /* Yes, we need to update curr before calling func(), because func() + might decide to remove the connection */ + struct connectdata *conn = curr->ptr; + curr = curr->next; + + if(1 == func(conn, param)) { + CONN_UNLOCK(data); + return TRUE; + } + } + } + CONN_UNLOCK(data); + return FALSE; +} + +/* Return the first connection found in the cache. Used when closing all + connections. + + NOTE: no locking is done here as this is presumably only done when cleaning + up a cache! +*/ +struct connectdata * +Curl_conncache_find_first_connection(struct conncache *connc) +{ + struct curl_hash_iterator iter; + struct curl_hash_element *he; + struct connectbundle *bundle; + + Curl_hash_start_iterate(&connc->hash, &iter); + + he = Curl_hash_next_element(&iter); + while(he) { + struct curl_llist_element *curr; + bundle = he->ptr; + + curr = bundle->conn_list.head; + if(curr) { + return curr->ptr; + } + + he = Curl_hash_next_element(&iter); + } + + return NULL; +} + +/* + * Give ownership of a connection back to the connection cache. Might + * disconnect the oldest existing in there to make space. + * + * Return TRUE if stored, FALSE if closed. + */ +bool Curl_conncache_return_conn(struct connectdata *conn) +{ + struct Curl_easy *data = conn->data; + + /* data->multi->maxconnects can be negative, deal with it. */ + size_t maxconnects = + (data->multi->maxconnects < 0) ? data->multi->num_easy * 4: + data->multi->maxconnects; + struct connectdata *conn_candidate = NULL; + + if(maxconnects > 0 && + Curl_conncache_size(data) > maxconnects) { + infof(data, "Connection cache is full, closing the oldest one.\n"); + + conn_candidate = Curl_conncache_extract_oldest(data); + + if(conn_candidate) { + /* Set the connection's owner correctly */ + conn_candidate->data = data; + + /* the winner gets the honour of being disconnected */ + (void)Curl_disconnect(conn_candidate, /* dead_connection */ FALSE); + } + } + CONN_LOCK(data); + conn->inuse = FALSE; /* Mark the connection unused */ + CONN_UNLOCK(data); + + return (conn_candidate == conn) ? FALSE : TRUE; + +} + +/* + * This function finds the connection in the connection bundle that has been + * unused for the longest time. + * + * Does not lock the connection cache! + * + * Returns the pointer to the oldest idle connection, or NULL if none was + * found. + */ +struct connectdata * +Curl_conncache_extract_bundle(struct Curl_easy *data, + struct connectbundle *bundle) +{ + struct curl_llist_element *curr; + timediff_t highscore = -1; + timediff_t score; + struct curltime now; + struct connectdata *conn_candidate = NULL; + struct connectdata *conn; + + (void)data; + + now = Curl_now(); + + curr = bundle->conn_list.head; + while(curr) { + conn = curr->ptr; + + if(!conn->inuse) { + /* Set higher score for the age passed since the connection was used */ + score = Curl_timediff(now, conn->now); + + if(score > highscore) { + highscore = score; + conn_candidate = conn; + } + } + curr = curr->next; + } + if(conn_candidate) { + /* remove it to prevent another thread from nicking it */ + bundle_remove_conn(bundle, conn_candidate); + data->state.conn_cache->num_conn--; + DEBUGF(infof(data, "The cache now contains %" + CURL_FORMAT_CURL_OFF_TU " members\n", + (curl_off_t) data->state.conn_cache->num_conn)); + } + + return conn_candidate; +} + +/* + * This function finds the connection in the connection cache that has been + * unused for the longest time and extracts that from the bundle. + * + * Returns the pointer to the connection, or NULL if none was found. + */ +struct connectdata * +Curl_conncache_extract_oldest(struct Curl_easy *data) +{ + struct conncache *connc = data->state.conn_cache; + struct curl_hash_iterator iter; + struct curl_llist_element *curr; + struct curl_hash_element *he; + timediff_t highscore =- 1; + timediff_t score; + struct curltime now; + struct connectdata *conn_candidate = NULL; + struct connectbundle *bundle; + struct connectbundle *bundle_candidate = NULL; + + now = Curl_now(); + + CONN_LOCK(data); + Curl_hash_start_iterate(&connc->hash, &iter); + + he = Curl_hash_next_element(&iter); + while(he) { + struct connectdata *conn; + + bundle = he->ptr; + + curr = bundle->conn_list.head; + while(curr) { + conn = curr->ptr; + + if(!conn->inuse) { + /* Set higher score for the age passed since the connection was used */ + score = Curl_timediff(now, conn->now); + + if(score > highscore) { + highscore = score; + conn_candidate = conn; + bundle_candidate = bundle; + } + } + curr = curr->next; + } + + he = Curl_hash_next_element(&iter); + } + if(conn_candidate) { + /* remove it to prevent another thread from nicking it */ + bundle_remove_conn(bundle_candidate, conn_candidate); + connc->num_conn--; + DEBUGF(infof(data, "The cache now contains %" + CURL_FORMAT_CURL_OFF_TU " members\n", + (curl_off_t) connc->num_conn)); + } + CONN_UNLOCK(data); + + return conn_candidate; +} + +void Curl_conncache_close_all_connections(struct conncache *connc) +{ + struct connectdata *conn; + + conn = Curl_conncache_find_first_connection(connc); + while(conn) { + SIGPIPE_VARIABLE(pipe_st); + conn->data = connc->closure_handle; + + sigpipe_ignore(conn->data, &pipe_st); + conn->data->easy_conn = NULL; /* clear the easy handle's connection + pointer */ + /* This will remove the connection from the cache */ + connclose(conn, "kill all"); + (void)Curl_disconnect(conn, FALSE); + sigpipe_restore(&pipe_st); + + conn = Curl_conncache_find_first_connection(connc); + } + + if(connc->closure_handle) { + SIGPIPE_VARIABLE(pipe_st); + sigpipe_ignore(connc->closure_handle, &pipe_st); + + Curl_hostcache_clean(connc->closure_handle, + connc->closure_handle->dns.hostcache); + Curl_close(connc->closure_handle); + sigpipe_restore(&pipe_st); + } +} + +#if 0 +/* Useful for debugging the connection cache */ +void Curl_conncache_print(struct conncache *connc) +{ + struct curl_hash_iterator iter; + struct curl_llist_element *curr; + struct curl_hash_element *he; + + if(!connc) + return; + + fprintf(stderr, "=Bundle cache=\n"); + + Curl_hash_start_iterate(connc->hash, &iter); + + he = Curl_hash_next_element(&iter); + while(he) { + struct connectbundle *bundle; + struct connectdata *conn; + + bundle = he->ptr; + + fprintf(stderr, "%s -", he->key); + curr = bundle->conn_list->head; + while(curr) { + conn = curr->ptr; + + fprintf(stderr, " [%p %d]", (void *)conn, conn->inuse); + curr = curr->next; + } + fprintf(stderr, "\n"); + + he = Curl_hash_next_element(&iter); + } +} +#endif |