Update networking layer w/ CURL and emscripten impl

2025-11-08 01:50:36 +11:00
parent a17925904d
commit f6874dc55a
4105 changed files with 694617 additions and 179 deletions
@@ -0,0 +1,131 @@
+---
+c: Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
+SPDX-License-Identifier: curl
+Title: CURLOPT_HTTP_VERSION
+Section: 3
+Source: libcurl
+Protocol:
+  - HTTP
+See-also:
+  - CURLOPT_ALTSVC (3)
+  - CURLOPT_HTTP09_ALLOWED (3)
+  - CURLOPT_HTTP200ALIASES (3)
+  - CURLOPT_SSLVERSION (3)
+Added-in: 7.9.1
+---
+
+# NAME
+
+CURLOPT_HTTP_VERSION - HTTP protocol version to use
+
+# SYNOPSIS
+
+~~~c
+#include <curl/curl.h>
+
+CURLcode curl_easy_setopt(CURL *handle, CURLOPT_HTTP_VERSION, long version);
+~~~
+
+# DESCRIPTION
+
+Pass *version* a long, set to one of the values described below. They ask
+libcurl to use the specific HTTP versions.
+
+Note that the HTTP version is just a request. libcurl still prioritizes to
+reuse existing connections so it might then reuse a connection using an HTTP
+version you have not asked for.
+
+## CURL_HTTP_VERSION_NONE
+
+We do not care about what version the library uses. libcurl uses whatever it
+thinks fit.
+
+## CURL_HTTP_VERSION_1_0
+
+Enforce HTTP 1.0 requests.
+
+## CURL_HTTP_VERSION_1_1
+
+Enforce HTTP 1.1 requests.
+
+## CURL_HTTP_VERSION_2_0
+
+Attempt HTTP 2 requests. libcurl falls back to HTTP 1.1 if HTTP 2 cannot be
+negotiated with the server.
+
+When libcurl uses HTTP/2 over HTTPS, it does not itself insist on TLS 1.2 or
+higher even though that is required by the specification. A user can add this
+version requirement with CURLOPT_SSLVERSION(3).
+
+The alias *CURL_HTTP_VERSION_2* was added to better reflect the actual
+protocol name.
+
+## CURL_HTTP_VERSION_2TLS
+
+Attempt HTTP 2 over TLS (HTTPS) only. libcurl falls back to HTTP 1.1 if HTTP 2
+cannot be negotiated with the HTTPS server. For clear text HTTP servers,
+libcurl uses 1.1.
+
+## CURL_HTTP_VERSION_2_PRIOR_KNOWLEDGE
+
+Issue non-TLS HTTP requests using HTTP/2 without HTTP/1.1 Upgrade. It requires
+prior knowledge that the server supports HTTP/2 straight away. HTTPS requests
+still do HTTP/2 the standard way with negotiated protocol version in the TLS
+handshake.
+
+Since 8.10.0 if this option is set for an HTTPS request then the application
+layer protocol version (ALPN) offered to the server is only HTTP/2. Prior to
+that both HTTP/1.1 and HTTP/2 were offered.
+
+## CURL_HTTP_VERSION_3
+
+(Added in 7.66.0) This option makes libcurl attempt to use HTTP/3 to the host
+given in the URL, with fallback to earlier HTTP versions if needed.
+
+## CURL_HTTP_VERSION_3ONLY
+
+(Added in 7.88.0) Setting this makes libcurl attempt to use HTTP/3 directly to
+server given in the URL and does not downgrade to earlier HTTP version if the
+server does not support HTTP/3.
+
+# DEFAULT
+
+Since curl 8.13.0: CURL_HTTP_VERSION_NONE
+
+Since curl 7.62.0: CURL_HTTP_VERSION_2TLS
+
+Before that: CURL_HTTP_VERSION_1_1
+
+# %PROTOCOLS%
+
+# EXAMPLE
+
+~~~c
+int main(void)
+{
+  CURL *curl = curl_easy_init();
+  if(curl) {
+    CURLcode ret;
+    curl_easy_setopt(curl, CURLOPT_URL, "https://example.com/");
+    curl_easy_setopt(curl, CURLOPT_HTTP_VERSION, CURL_HTTP_VERSION_2TLS);
+    ret = curl_easy_perform(curl);
+    if(ret == CURLE_HTTP_RETURNED_ERROR) {
+      /* an HTTP response error problem */
+    }
+  }
+}
+~~~
+
+# HISTORY
+
+**CURL_HTTP_VERSION_*** enums became `long` types in 8.13.0, prior to this
+version a `long` cast was necessary when passed to curl_easy_setopt(3).
+
+# %AVAILABILITY%
+
+# RETURN VALUE
+
+curl_easy_setopt(3) returns a CURLcode indicating success or error.
+
+CURLE_OK (0) means everything was OK, non-zero means an error occurred, see
+libcurl-errors(3).