Toy Finger Daemon
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The finger protocol is defined in RFC742. It’s a pretty simple protocol. I’d like to have a more useful output at some point, perhaps including status updates from Mastodon or APRS, but for now I’ve got the hang of reading the request and sending some output with some simple C program.
It uses inetd just like the Gopher server.
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
static __dead void
handle_query(char *input, int len)
{
if (len == 0) {
printf("Summary:\n\n");
printf("-USER-\n");
printf("irl\n");
} else if (len == 3 && memcmp(input, "irl", 3) == 0) {
printf("+-----+\n");
printf("| irl |\n");
printf("+-----+\n");
printf("\n");
printf(" gopher://irl.xyz/1/\n");
printf(" sip:[email protected]\n");
printf(" https://iain.learmonth.me/\n");
printf(" https://hackers.town/@irl/\n");
printf(" mailto:[email protected]\n");
} else {
printf("Unknown input of %d bytes\n", len);
}
exit(0);
}
int
main(int argc, char **argv)
{
char input[256];
int i, pos = 0;
while (pos < 256)
{
pos += read(0, &input[pos], 256 - pos);
for (i = 0; i < pos; i++)
{
if (input[i] == '\r' || input[i] == '\n')
handle_query(input, i);
}
}
printf("Invalid\n");
}