lib: connect/h2/h3 refactor

Refactoring of connection setup and happy eyeballing. Move
nghttp2. ngtcp2, quiche and msh3 into connection filters.

 - eyeballing cfilter that uses sub-filters for performing parallel connects
 - socket cfilter for all transport types, including QUIC
 - QUIC implementations in cfilter, can now participate in eyeballing
 - connection setup is more dynamic in order to adapt to what filter did
   really connect.  Relevant to see if a SSL filter needs to be added or
   if SSL has already been provided
 - HTTP/3 test cases similar to HTTP/2
 - multiuse of parallel transfers for HTTP/3, tested for ngtcp2 and quiche

 - Fix for data attach/detach in VTLS filters that could lead to crashes
   during parallel transfers.
 - Eliminating setup() methods in cfilters, no longer needed.
 - Improving Curl_conn_is_alive() to replace Curl_connalive() and
   integrated ssl alive checks into cfilter.
 - Adding CF_CNTRL_CONN_INFO_UPDATE to tell filters to update
   connection into and persist it at the easy handle.

 - Several more cfilter related cleanups and moves:
   - stream_weigth and dependency info is now wrapped in struct
     Curl_data_priority
   - Curl_data_priority members depend is available in HTTP2|HTTP3
   - Curl_data_priority members depend on NGHTTP2 support
   - handling init/reset/cleanup of priority part of url.c
   - data->state.priority same struct, but shallow copy for compares only

 - PROTOPT_STREAM has been removed
   - Curl_conn_is_mulitplex() now available to check on capability

 - Adding query method to connection filters.
   - ngtcp2+quiche: implementing query for max concurrent transfers.

 - Adding is_alive and keep_alive cfilter methods. Adding DATA_SETUP event.
   - setting keepalive timestamp on connect
   - DATA_SETUP is called after the connection has been completely
     setup (but may not connected yet) to allow filters to initialize
     data members they use.

 - there is no socket to be had with msh3, it is unclear how select
   shall work

 - manual test via "curl --http3 https://curl.se" fail with "empty
   reply from server".

 - Various socket/conn related cleanups:
   - Curl_socket is now Curl_socket_open and in cf-socket.c
   - Curl_closesocket is now Curl_socket_close and in cf-socket.c
   - Curl_ssl_use has been replaced with Cur_conn_is_ssl
   - Curl_conn_tcp_accepted_set has been split into
     Curl_conn_tcp_listen_set and Curl_conn_tcp_accepted_set
     with a clearer purpose

Closes #10141

1 files changed, 29 insertions, 39 deletions

diff --git a/lib/urldata.h b/lib/urldata.h
index 82cc340d1..a70729c7e 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -123,9 +123,9 @@ typedef unsigned int curl_prot_t;
 #define DMSGI(d,i,msg)  \
   "[CONN-%ld-%d] "msg, (d)->conn->connection_id, (i)
 #define CMSG(c,msg)  \
-  "[CONN-%ld] "msg, (conn)->connection_id
+  "[CONN-%ld] "msg, (c)->connection_id
 #define CMSGI(c,i,msg)  \
-  "[CONN-%ld-%d] "msg, (conn)->connection_id, (i)
+  "[CONN-%ld-%d] "msg, (c)->connection_id, (i)
 #define CFMSG(cf,msg)  \
   "[CONN-%ld-%d][CF-%s] "msg, (cf)->conn->connection_id, \
   (cf)->sockindex, (cf)->cft->name
@@ -187,7 +187,6 @@ typedef CURLcode (*Curl_datastream)(struct Curl_easy *data,
 #include "mqtt.h"
 #include "wildcard.h"
 #include "multihandle.h"
-#include "quic.h"
 #include "c-hyper.h"
 
 #ifdef HAVE_GSSAPI
@@ -830,7 +829,7 @@ struct Curl_handler {
 #define PROTOPT_CREDSPERREQUEST (1<<7) /* requires login credentials per
                                           request instead of per connection */
 #define PROTOPT_ALPN (1<<8) /* set ALPN for this */
-#define PROTOPT_STREAM (1<<9) /* a protocol with individual logical streams */
+/* (1<<9) was PROTOPT_STREAM, now free */
 #define PROTOPT_URLOPTIONS (1<<10) /* allow options part in the userinfo field
                                       of the URL */
 #define PROTOPT_PROXY_AS_HTTP (1<<11) /* allow this non-HTTP scheme over a
@@ -912,13 +911,7 @@ struct connectdata {
   /* 'ip_addr' is the particular IP we connected to. It points to a struct
      within the DNS cache, so this pointer is only valid as long as the DNS
      cache entry remains locked. It gets unlocked in multi_done() */
-  struct Curl_addrinfo *ip_addr;
-  struct Curl_addrinfo *tempaddr[2]; /* for happy eyeballs */
-
-#ifdef ENABLE_QUIC
-  struct quicsocket hequic[2]; /* two, for happy eyeballs! */
-  struct quicsocket *quic;
-#endif
+  const struct Curl_addrinfo *ip_addr;
 
   struct hostname host;
   char *hostname_resolve; /* host name to resolve to address, allocated */
@@ -947,8 +940,6 @@ struct connectdata {
   struct curltime lastused; /* when returned to the connection cache */
   curl_socket_t sock[2]; /* two sockets, the second is used for the data
                             transfer when doing FTP */
-  curl_socket_t tempsock[2]; /* temporary sockets for happy eyeballs */
-  int tempfamily[2]; /* family used for the temp sockets */
   Curl_recv *recv[2];
   Curl_send *send[2];
   struct Curl_cfilter *cfilter[2]; /* connection filters */
@@ -962,16 +953,6 @@ struct connectdata {
 #endif
   struct ConnectBits bits;    /* various state-flags for this connection */
 
- /* connecttime: when connect() is called on the current IP address. Used to
-    be able to track when to move on to try next IP - but only when the multi
-    interface is used. */
-  struct curltime connecttime;
-
-  /* The field below gets set in Curl_connecthost */
-  /* how long time in milliseconds to spend on trying to connect to each IP
-     address, per family */
-  timediff_t timeoutms_per_addr[2];
-
   const struct Curl_handler *handler; /* Connection's protocol handler */
   const struct Curl_handler *given;   /* The protocol first given */
 
@@ -1043,9 +1024,6 @@ struct connectdata {
 #ifndef CURL_DISABLE_FTP
     struct ftp_conn ftpc;
 #endif
-#ifndef CURL_DISABLE_HTTP
-    struct http_conn httpc;
-#endif
 #ifdef USE_SSH
     struct ssh_conn sshc;
 #endif
@@ -1094,7 +1072,7 @@ struct connectdata {
 #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
   int socks5_gssapi_enctype;
 #endif
-  /* The field below gets set in Curl_connecthost */
+  /* The field below gets set in connect.c:connecthost() */
   int num_addr; /* number of addresses to try to connect to */
   int port;        /* which port to use locally - to connect to */
   int remote_port; /* the remote port, not the proxy port! */
@@ -1240,10 +1218,29 @@ struct auth {
                    should be RFC compliant */
 };
 
-struct Curl_http2_dep {
-  struct Curl_http2_dep *next;
+#ifdef USE_NGHTTP2
+struct Curl_data_prio_node {
+  struct Curl_data_prio_node *next;
   struct Curl_easy *data;
 };
+#endif
+
+/**
+ * Priority information for an easy handle in relation to others
+ * on the same connection.
+ * TODO: we need to adapt it to the new priority scheme as defined in RFC 9218
+ */
+struct Curl_data_priority {
+#ifdef USE_NGHTTP2
+  /* tree like dependencies only implemented in nghttp2 */
+  struct Curl_easy *parent;
+  struct Curl_data_prio_node *children;
+#endif
+  int weight;
+#ifdef USE_NGHTTP2
+  BIT(exclusive);
+#endif
+};
 
 /*
  * This struct is for holding data that was attempted to get sent to the user's
@@ -1391,14 +1388,11 @@ struct UrlState {
   size_t drain; /* Increased when this stream has data to read, even if its
                    socket is not necessarily is readable. Decreased when
                    checked. */
+  struct Curl_data_priority priority; /* shallow coyp of data->set */
 #endif
 
   curl_read_callback fread_func; /* read callback/function */
   void *in;                      /* CURLOPT_READDATA */
-#ifdef USE_HTTP2
-  struct Curl_easy *stream_depends_on;
-  int stream_weight;
-#endif
   CURLU *uh; /* URL handle for the current parsed URL */
   struct urlpieces up;
   unsigned char httpreq; /* Curl_HttpReq; what kind of HTTP request (if any)
@@ -1469,7 +1463,6 @@ struct UrlState {
   BIT(done); /* set to FALSE when Curl_init_do() is called and set to TRUE
                 when multi_done() is called, to prevent multi_done() to get
                 invoked twice when the multi interface is used. */
-  BIT(stream_depends_e); /* set or don't set the Exclusive bit */
   BIT(previouslypending); /* this transfer WAS in the multi->pending queue */
   BIT(cookie_engine);
   BIT(prefer_ascii);   /* ASCII rather than binary */
@@ -1789,10 +1782,8 @@ struct UserDefined {
   size_t maxconnects;    /* Max idle connections in the connection cache */
 
   long expect_100_timeout; /* in milliseconds */
-#ifdef USE_HTTP2
-  struct Curl_easy *stream_depends_on;
-  int stream_weight;
-  struct Curl_http2_dep *stream_dependents;
+#if defined(USE_HTTP2) || defined(USE_HTTP3)
+  struct Curl_data_priority priority;
 #endif
   curl_resolver_start_callback resolver_start; /* optional callback called
                                                   before resolver start */
@@ -1884,7 +1875,6 @@ struct UserDefined {
   BIT(suppress_connect_headers); /* suppress proxy CONNECT response headers
                                     from user callbacks */
   BIT(dns_shuffle_addresses); /* whether to shuffle addresses before use */
-  BIT(stream_depends_e); /* set or don't set the Exclusive bit */
   BIT(haproxyprotocol); /* whether to send HAProxy PROXY protocol v1
                            header */
   BIT(abstract_unix_socket);