Example Programs¶

Standalone programs for testing and learning. All are built by default.

cmake -B build -DBUILD_EXAMPLES=ON
cmake --build build

Binaries are in build/bin/.

server (build/bin/server)¶

Minimal QUIC/HTTP/3 server. Serves files from the current working directory; returns a 20-byte body for unknown paths. Single-threaded, one connection at a time.

Source: mod_http3/examples/server.c

Generate a certificate and start:

bash scripts/mkcert.sh keys
./build/bin/server 4433 keys/server.crt keys/server.key &

Verify:

ss -ulnp | grep 4433
# UNCONN 0 0 0.0.0.0:4433 0.0.0.0:*

Test with the built-in client:

./build/bin/quic_client_test localhost 4433 keys/server.crt

Test with curl:

/opt/curl/bin/curl --http3 --cacert keys/server.crt -sI https://localhost:4433/

Test with Chrome:

google-chrome \
    --user-data-dir=/tmp/quic_dev \
    --ignore-certificate-errors \
    --origin-to-force-quic-on=localhost:4433 \
    https://localhost:4433

Stop:

pkill -f "build/bin/server"

Behavior:

Request Path	Response
`/` or unknown	20-byte default body (`12345678901234567890`)
`/filename`	Contents of `./filename` if it exists
`HEAD` method	Headers only, no body
`GET` method	Headers + body

Limitations: Single-threaded, no HTTP/2 or HTTP/1.1 fallback, no Alt-Svc header, no TLS session resumption.

quic_client_test (build/bin/quic_client_test)¶

Native QUIC/HTTP/3 client. Sends one or more concurrent GET requests. Verifies the server certificate against a supplied CA cert. No curl needed.

Source: mod_http3/examples/quic_client_test.c

Start a server first:

bash scripts/mkcert.sh keys
./build/bin/server 4433 keys/server.crt keys/server.key &

Single stream:

./build/bin/quic_client_test localhost 4433 keys/server.crt

Expected: Status 200, All streams complete.

Five concurrent streams:

./build/bin/quic_client_test localhost 4433 keys/server.crt 5

TLS handshake trace (writes trace.txt):

./build/bin/quic_client_test -trace localhost 4433 keys/server.crt

Usage:

./build/bin/quic_client_test [-trace] <hostname> <port> <cacert.pem> [num_streams]

Argument	Description
`-trace`	Write TLS message trace to `trace.txt`
`hostname`	Server hostname (e.g., `localhost`)
`port`	Server UDP port (e.g., `4433`)
`cacert.pem`	CA certificate to verify the server
`num_streams`	Number of concurrent HTTP/3 GET streams (default: 1)

Limitations: Sends GET requests only, requests root path / only, no HTTP/2 or HTTP/1.1 fallback.

quic_server_test (build/bin/quic_server_test)¶

DO NOT USE. This test is broken. Both QUIC_TSERVER instances try to handshake with an external address that does not exist, so the test hangs indefinitely.

Use build/bin/server + build/bin/quic_client_test instead.

Source: mod_http3/examples/quic_server_test.c

biomemexample (build/bin/biomemexample)¶

Demonstrates OpenSSL BIO memory buffers. fork()s into client and server processes that perform a TLS handshake over Unix pipes using memory BIOs (BIO_s_mem). Not QUIC or HTTP/3 related - an OpenSSL BIO learning example.

Source: mod_http3/examples/biomemexample.c

Run:

./build/bin/biomemexample

The client sends "abcdefgh", the server sends "ABCDEFGH". Both print what they sent and received.

apr_miniserver (build/bin/apr_miniserver)¶

Minimal UDP server using APR socket types. Listens on UDP port 8081, spawns a thread per datagram, prints received data. Not QUIC or HTTP/3 related - an APR learning example.

Source: mod_http3/examples/miniserver.c

Run:

./build/bin/apr_miniserver &

Send a message:

echo "hello" > /dev/udp/localhost/8081

Server output:

from: <source port>
from: 127.0.0.1
from: hello

Stop:

pkill -f apr_miniserver