smtp: use the upload buffer size for scratch buffer malloc

[platform/upstream/curl.git] / docs / HTTP2.md

diff --git a/docs/HTTP2.md b/docs/HTTP2.md
index bf53820..efbe699 100644 (file)
--- a/docs/HTTP2.md
+++ b/docs/HTTP2.md
@@ -7,7 +7,8 @@ HTTP/2 with curl
 Build prerequisites
 -------------------
   - nghttp2
-  - OpenSSL, NSS, GnutTLS or PolarSSL with a new enough version
+  - OpenSSL, libressl, BoringSSL, NSS, GnutTLS, mbedTLS, wolfSSL or SChannel
+    with a new enough version.
 
 [nghttp2](https://nghttp2.org/)
 -------------------------------
@@ -51,13 +52,17 @@ SSL libs
 --------
 
 The challenge is the ALPN and NPN support and all our different SSL
-backends. You may need a fairly updated SSL library version for it to
-provide the necessary TLS features. Right now we support:
-
-  - OpenSSL:  ALPN and NPN
-  - NSS:      ALPN and NPN
-  - GnuTLS:   ALPN
-  - PolarSSL: ALPN
+backends. You may need a fairly updated SSL library version for it to provide
+the necessary TLS features. Right now we support:
+
+  - OpenSSL:   ALPN and NPN
+  - libressl:  ALPN and NPN
+  - BoringSSL: ALPN and NPN
+  - NSS:       ALPN and NPN
+  - GnuTLS:    ALPN
+  - mbedTLS:   ALPN
+  - SChannel:  ALPN
+  - wolfSSL:   ALPN
 
 Multiplexing
 ------------
@@ -91,21 +96,31 @@ curl tool
 
 curl offers the `--http2` command line option to enable use of HTTP/2.
 
+curl offers the `--http2-prior-knowledge` command line option to enable use of
+HTTP/2 without HTTP/1.1 Upgrade.
+
 Since 7.47.0, the curl tool enables HTTP/2 by default for HTTPS connections.
 
+curl tool limitations
+---------------------
+
+The command line tool won't do any HTTP/2 multiplexing even though libcurl
+supports it, simply because the curl tool is not written to take advantage of
+the libcurl API that's necessary for this (the multi interface). We have an
+outstanding TODO item for this and **you** can help us make it happen.
+
+The command line tool also doesn't support HTTP/2 server push for the same
+reason it doesn't do multiplexing: it needs to use the multi interface for
+that so that multiplexing is supported.
+
 HTTP Alternative Services
 -------------------------
 
-Alt-Svc is a suggested extension with a corresponding frame (ALTSVC) in HTTP/2
-that tells the client about an alternative "route" to the same content for the
-same origin server that you get the response from. A browser or long-living
-client can use that hint to create a new connection asynchronously.  For
-libcurl, we may introduce a way to bring such clues to the applicaton and/or
-let a subsequent request use the alternate route
-automatically. [Spec](https://tools.ietf.org/html/draft-ietf-httpbis-alt-svc-14)
-
-TODO
-----
+Alt-Svc is an extension with a corresponding frame (ALTSVC) in HTTP/2 that
+tells the client about an alternative "route" to the same content for the same
+origin server that you get the response from. A browser or long-living client
+can use that hint to create a new connection asynchronously.  For libcurl, we
+may introduce a way to bring such clues to the application and/or let a
+subsequent request use the alternate route automatically.
 
-  - Implement "prior-knowledge" HTTP/2 connections over clear text so that
-    curl can connect with HTTP/2 at once without 1.1+Upgrade.
+[Detailed in RFC 7838](https://tools.ietf.org/html/rfc7838)