micro_proxy is a very small HTTP/HTTPS proxy. It runs from inetd, which means its performance is poor. But for low-traffic sites, it's quite adequate. It implements all the basic features of an HTTP/HTTPS proxy, in only 260 lines of code.
To install it, add a line like this to /etc/inetd.conf:
webproxy stream tcp nowait nobody /usr/sbin/micro_proxy micro_proxyMake sure the path to the executable is correct. Then add a line like this to /etc/services:
webproxy port/tcpChange "port" to the port number you want to use - 3128, or whatever. Then restart inetd by sending it a "HUP" signal, or rebooting.
On some systems, inetd has a maximum spawn rate - if you try to run inetd services faster than a certain number of times per minute, it assumed there's either a bug of an attack going on and it shuts down for a few minutes. If you run into this problem - look for syslog messages about too-rapid looping - you'll need to find out how to increase the limit. Unfortunately this varies from OS to OS. On FreeBSD, you add a "-R 10000" flag to inetd's initial command line. On some Linux systems, you can set the limit on a per-service basis in inetd.conf, by changing "nowait" to "nowait.10000".