Start working on the frontend

.gitignore

@@ -2,4 +2,5 @@
 *.o
 ethertype-dump
 arp-request
+ethermess-backend
 ethermess

Makefile

@@ -2,19 +2,23 @@ DESTDIR ?=
 PREFIX ?= /usr/local
 EXEC_PREFIX ?= $(PREFIX)
 BINDIR ?= $(DESTDIR)$(EXEC_PREFIX)/bin
+LIBEXECDIR ?= $(DESTDIR)$(EXEC_PREFIX)/libexec
 
 CFLAGS += -Os -g -Wall -Wextra -pedantic
 CPPFLAGS +=
 LDFLAGS +=
 
+SED ?= sed
+
 BINS := ethertype-dump arp-request ethermess
+LIBEXECS := ethermess-backend
 
 .SUFFIXES:
 .SUFFIXES: .c .o
 
 .PHONY: all install uninstall clean distclean
 
-all: $(BINS)
+all: $(BINS) $(LIBEXECS)
 
 ethertype-dump: ethertype-dump.o
 	$(CC) -o $@ $< $(LDFLAGS)
@@ -22,19 +26,29 @@ ethertype-dump: ethertype-dump.o
 arp-request: arp-request.o
 	$(CC) -o $@ $< $(LDFLAGS)
 
-ethermess: ethermess.o
+ethermess: ethermess.py
+	# I'm not sure you can make this work 100% with traditional make
+	#$(SED) "2s/__LIBEXECDIR__/'`printf "%s" "$(LIBEXECDIR)" | sed "s,\\\\\\\\,\\\\\\\\\\\\\\\\,g;s,/,\\\\\\\\/,g;s,"'"'",\\\\\\\\"'"'",g"`'/" < $< > $@
+	$(SED) "2s/__LIBEXECDIR__/'.'/" < $< > $@ #debg
+	chmod +x $@
+
+ethermess-backend: ethermess-backend.o
 	$(CC) -o $@ $< $(LDFLAGS)
 
 .c.o:
 	$(CC) -c $(CFLAGS) $(CPPFLAGS) -o $@ $<
 
-install: $(BINS)
+install: $(BINS) $(LIBEXECS)
+	mkdir -p $(BINDIR)
+	mkdir -p $(LIBEXECDIR)
 	install $(BINS) $(BINDIR)
+	install $(LIBEXECS) $(LIBEXECDIR)
 
 uninstall:
 	cd $(BINDIR) && rm $(BINS)
+	cs $(LIBEXECDIR) && rm $(LIBEXECS)
 
 clean:
-	rm -f ethertype-dump *.o
+	rm -f $(BINS) $(LIBEXECS) *.o
 
 distclean: clean

ethermess-backend.c

@@ -405,6 +405,43 @@ void send_ack(const unsigned char destination[6], uint16_t msgid) {
 	send_frame(frame, sizeof(frame));
 }
 
+void readallx(int fd, unsigned char *buf, size_t length) {
+	size_t completed = 0;
+	while (completed < length) {
+		ssize_t res = read(fd, &buf[completed], length - completed);
+		if (res == -1) {
+			err(1, "read");
+		}
+		completed += res;
+	}
+}
+
+void writeallx(int fd, unsigned char *buf, size_t length) {
+	size_t completed = 0;
+	while (completed < length) {
+		ssize_t res = write(fd, &buf[completed], length - completed);
+		if (res == -1) {
+			err(1, "write");
+		}
+		completed += res;
+	}
+}
+
+void read_status(void) {
+	unsigned char status;
+	readallx(0, &status, 1);
+	if (status != EMS_AVAILABLE && status != EMS_UNAVAILABLE && status != EMS_OFFLINE) {
+		errx(1, "Frontend sent a status %u that we don't understand", status);
+	}
+
+	unsigned char length;
+	readallx(0, &length, 1);
+
+	readallx(0, own_nick, length);
+
+	own_nick_length = length;
+}
+
 void read_command(void) {
 	int cmd = getchar();
 	if (cmd == EOF) {
@@ -1068,18 +1105,12 @@ int main(int argc, char **argv) {
 		err(1, "fflush");
 	}
 
-	// Set our nick
-	if (memcmp(own_mac, veth0a_mac, 6) == 0) {
-		memcpy(own_nick, "𐀀ab", 6);
-		own_nick_length = 6;
-	} else {
-		memcpy(own_nick, "ࠀ<EFBFBD>", 6);
-		own_nick_length = 6;
-	}
-
 	// Initialize the message id cache
 	memset(msgid_cache, 0, sizeof(msgid_cache));
 
+	// Set our status and nick
+	read_status();
+
 	// Broadcast our status to the network to let them know we're here
 	send_status(broadcast_mac);
 

ethermess.py

@@ -0,0 +1,2 @@
+#!/usr/bin/env python3
+libexec_dir = __LIBEXECDIR__