After running make examples, if SSL is enabled, you can quickly test HTTPS, with optional client-based certificate authentication using the following process within the build directory:

# do all the stupid ssl generation
./examples/https/bin/generate.sh

# Test without client auth

# Run the server
./examples/example_https_server       \
  -cert examples/https/server-crt.pem \
  -key  examples/https/server-key.pem \
  -verify-client off

# Make a request
curl -vk https://localhost:4443/

# Test WITH client auth

./examples/example_https_server       \
  -cert examples/https/server-crt.pem \
  -key  examples/https/server-key.pem \
  -ca   examples/https/ca-crt.pem     \
  -verify-client on                   \
  -verify-depth  2

# Make a request with the client key
curl -kv \
  --key  examples/https/client1-key.pem \
  --cert examples/https/client1-crt.pem \
  https://localhost:4443/

The output (with client-certs) should look like:

< HTTP/1.1 200 OK
< X-SSL-Subject: /C=US/ST=MA/L=Boston/O=Critical Stack/OU=evhtp/CN=client1/emailAddress=nate@cl0d.com
< X-SSL-Issuer: /C=US/ST=MA/L=Boston/O=Critical Stack/OU=evhtp/CN=ca/emailAddress=nate@cl0d.com
< X-SSL-Notbefore: Dec  7 16:10:34 2017 GMT
< X-SSL-Notafter: Sep  1 16:10:34 2020 GMT
< X-SSL-Serial: 57459A54BD08848C6D1546C2733EAD8A03553670
< X-SSL-Cipher: ECDHE-RSA-AES256-GCM-SHA384
< X-SSL-Sha1: 7A:68:47:CD:79:18:FF:DA:65:BC:67:6B:C2:5D:F3:66:9A:4A:64:7A
< X-SSL-Certificate: -----BEGIN CERTIFICATE-----
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< 	BQAwfzELMAkGA1UEBhMCVVMxCzAJBgNVBAgMAk1BMQ8wDQYDVQQHDAZCb3N0b24x
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< 	EKX/dKNiqoJSqOEDSsCN6jSJ7uTr5do+7xydqOcTQ+gI3FQsC1NjseqRRU0Q4HVL
< 	95crEmqxlOxOjcrQK6U36HyKfn7EJ1B6/SJM8U9abOKBRUQjgLlrC6GaA/rToHmX
< 	mlkqw2nKTnZhvIGmi0UjwtOD8rQnGahnq+jwoQV6Ag2YbSfeygvajJvdLBjEBYm+
< 	5F6nQgv3JR9iJoS9AxcCEURH7jIAfdbYT6RBT3VARZyPcPtLSMFLLcXh0Z/Egifi
< 	f+xTIL7mCgdW2Jp5s8cNjhrWk6dJVaXwwA6MNSfDeWeu7uHRm3Ir0Jwoe5I2pENm
< 	mKueI6EhIKc6tdQWS6t+ZM0IJsVvhh4s0FqeUFYCP7RxG+P4u5wZxHdjbfUUJ8zA
< 	xHMrDvO8p6dwRUDAPkOqCPpdGmBky/ukBXNi2u0OOJ+wUgoA
< 	-----END CERTIFICATE-----
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