hare

commit 6b38b891ce50c16b29d8edf74734ac1acc5090d0
parent d1d410824213c6876e3105c59d2aa9e5030efcd5
Author: Drew DeVault <sir@cmpwn.com>
Date:   Mon, 21 Jun 2021 12:27:09 -0400

unix::hosts: new module

Signed-off-by: Drew DeVault <sir@cmpwn.com>

Diffstat:
M
scripts/gen-stdlib
 | 
9
++++++++-
M
stdlib.mk
 | 
32
++++++++++++++++++++++++++++++--
A
unix/hosts/lookup.ha
 | 
50
++++++++++++++++++++++++++++++++++++++++++++++++++

3 files changed, 88 insertions(+), 3 deletions(-)
diff --git a/scripts/gen-stdlib b/scripts/gen-stdlib
@@ -753,6 +753,12 @@ unix() {
 	gen_ssa unix errors
 }
 
+unix_hosts() {
+	gen_srcs unix::hosts \
+        lookup.ha
+	gen_ssa unix::hosts os io bufio net::ip strings
+}
+
 unix_passwd() {
 	gen_srcs unix::passwd \
 		group.ha \
@@ -764,7 +770,7 @@ unix_passwd() {
 unix_resolvconf() {
 	gen_srcs unix::resolvconf \
         load.ha
-	gen_ssa unix::resolvconf os io bufio net::ip
+	gen_ssa unix::resolvconf os io bufio net::ip strings
 }
 
 unix_tty() {
@@ -845,6 +851,7 @@ time
 types
 unicode
 unix
+unix::hosts
 unix::passwd
 unix::resolvconf
 unix::tty
diff --git a/stdlib.mk b/stdlib.mk
@@ -321,6 +321,10 @@ hare_stdlib_deps+=$(stdlib_unicode)
 stdlib_unix=$(HARECACHE)/unix/unix.o
 hare_stdlib_deps+=$(stdlib_unix)
 
+# gen_lib unix::hosts
+stdlib_unix_hosts=$(HARECACHE)/unix/hosts/unix_hosts.o
+hare_stdlib_deps+=$(stdlib_unix_hosts)
+
 # gen_lib unix::passwd
 stdlib_unix_passwd=$(HARECACHE)/unix/passwd/unix_passwd.o
 hare_stdlib_deps+=$(stdlib_unix_passwd)
@@ -1068,6 +1072,16 @@ $(HARECACHE)/unix/unix.ssa: $(stdlib_unix_srcs) $(stdlib_rt) $(stdlib_errors)
 	@HARECACHE=$(HARECACHE) $(HAREC) $(HAREFLAGS) -o $@ -Nunix \
 		-t$(HARECACHE)/unix/unix.td $(stdlib_unix_srcs)
 
+# unix::hosts
+stdlib_unix_hosts_srcs= \
+	$(STDLIB)/unix/hosts/lookup.ha
+
+$(HARECACHE)/unix/hosts/unix_hosts.ssa: $(stdlib_unix_hosts_srcs) $(stdlib_rt) $(stdlib_os) $(stdlib_io) $(stdlib_bufio) $(stdlib_net_ip) $(stdlib_strings)
+	@printf 'HAREC \t$@\n'
+	@mkdir -p $(HARECACHE)/unix/hosts
+	@HARECACHE=$(HARECACHE) $(HAREC) $(HAREFLAGS) -o $@ -Nunix::hosts \
+		-t$(HARECACHE)/unix/hosts/unix_hosts.td $(stdlib_unix_hosts_srcs)
+
 # unix::passwd
 stdlib_unix_passwd_srcs= \
 	$(STDLIB)/unix/passwd/group.ha \
@@ -1084,7 +1098,7 @@ $(HARECACHE)/unix/passwd/unix_passwd.ssa: $(stdlib_unix_passwd_srcs) $(stdlib_rt
 stdlib_unix_resolvconf_srcs= \
 	$(STDLIB)/unix/resolvconf/load.ha
 
-$(HARECACHE)/unix/resolvconf/unix_resolvconf.ssa: $(stdlib_unix_resolvconf_srcs) $(stdlib_rt) $(stdlib_os) $(stdlib_io) $(stdlib_bufio) $(stdlib_net_ip)
+$(HARECACHE)/unix/resolvconf/unix_resolvconf.ssa: $(stdlib_unix_resolvconf_srcs) $(stdlib_rt) $(stdlib_os) $(stdlib_io) $(stdlib_bufio) $(stdlib_net_ip) $(stdlib_strings)
 	@printf 'HAREC \t$@\n'
 	@mkdir -p $(HARECACHE)/unix/resolvconf
 	@HARECACHE=$(HARECACHE) $(HAREC) $(HAREFLAGS) -o $@ -Nunix::resolvconf \
@@ -1437,6 +1451,10 @@ hare_testlib_deps+=$(testlib_unicode)
 testlib_unix=$(TESTCACHE)/unix/unix.o
 hare_testlib_deps+=$(testlib_unix)
 
+# gen_lib unix::hosts
+testlib_unix_hosts=$(TESTCACHE)/unix/hosts/unix_hosts.o
+hare_testlib_deps+=$(testlib_unix_hosts)
+
 # gen_lib unix::passwd
 testlib_unix_passwd=$(TESTCACHE)/unix/passwd/unix_passwd.o
 hare_testlib_deps+=$(testlib_unix_passwd)
@@ -2208,6 +2226,16 @@ $(TESTCACHE)/unix/unix.ssa: $(testlib_unix_srcs) $(testlib_rt) $(testlib_errors)
 	@HARECACHE=$(TESTCACHE) $(HAREC) $(TESTHAREFLAGS) -o $@ -Nunix \
 		-t$(TESTCACHE)/unix/unix.td $(testlib_unix_srcs)
 
+# unix::hosts
+testlib_unix_hosts_srcs= \
+	$(STDLIB)/unix/hosts/lookup.ha
+
+$(TESTCACHE)/unix/hosts/unix_hosts.ssa: $(testlib_unix_hosts_srcs) $(testlib_rt) $(testlib_os) $(testlib_io) $(testlib_bufio) $(testlib_net_ip) $(testlib_strings)
+	@printf 'HAREC \t$@\n'
+	@mkdir -p $(TESTCACHE)/unix/hosts
+	@HARECACHE=$(TESTCACHE) $(HAREC) $(TESTHAREFLAGS) -o $@ -Nunix::hosts \
+		-t$(TESTCACHE)/unix/hosts/unix_hosts.td $(testlib_unix_hosts_srcs)
+
 # unix::passwd
 testlib_unix_passwd_srcs= \
 	$(STDLIB)/unix/passwd/group.ha \
@@ -2224,7 +2252,7 @@ $(TESTCACHE)/unix/passwd/unix_passwd.ssa: $(testlib_unix_passwd_srcs) $(testlib_
 testlib_unix_resolvconf_srcs= \
 	$(STDLIB)/unix/resolvconf/load.ha
 
-$(TESTCACHE)/unix/resolvconf/unix_resolvconf.ssa: $(testlib_unix_resolvconf_srcs) $(testlib_rt) $(testlib_os) $(testlib_io) $(testlib_bufio) $(testlib_net_ip)
+$(TESTCACHE)/unix/resolvconf/unix_resolvconf.ssa: $(testlib_unix_resolvconf_srcs) $(testlib_rt) $(testlib_os) $(testlib_io) $(testlib_bufio) $(testlib_net_ip) $(testlib_strings)
 	@printf 'HAREC \t$@\n'
 	@mkdir -p $(TESTCACHE)/unix/resolvconf
 	@HARECACHE=$(TESTCACHE) $(HAREC) $(TESTHAREFLAGS) -o $@ -Nunix::resolvconf \
diff --git a/unix/hosts/lookup.ha b/unix/hosts/lookup.ha
@@ -0,0 +1,50 @@
+use bufio;
+use io;
+use net::ip;
+use os;
+use strings;
+
+// XXX: Different platforms may want to configure a different path
+def path: str = "/etc/hosts";
+
+// Looks up a host from /etc/hosts. Aborts the program if the file does not
+// exist, is written in an invalid format, or if any other error occurs.
+export fn lookup(name: str) (ip::addr | void) = {
+	// XXX: Would be cool if we could do this without allocating anything
+	// XXX: Would be cool to add caching
+	const file = os::open(path)!;
+	defer io::close(file);
+
+	for (true) {
+		const line = match (bufio::scanline(file)) {
+			io::EOF => break,
+			line: []u8 => line,
+		};
+		defer free(line);
+		if (line[0] == '#': u32: u8) {
+			continue;
+		};
+
+		const scanner = bufio::fixed(line, io::mode::READ);
+		defer io::close(scanner);
+
+		const tok = match (bufio::scantok(scanner, ' ', '\t')!) {
+			io::EOF => break,
+			tok: []u8 => tok,
+		};
+		defer free(tok);
+		const addr = ip::parse(strings::fromutf8(tok))!;
+
+		for (true) {
+			const tok = match (bufio::scantok(scanner, ' ', '\t')!) {
+				io::EOF => break,
+				tok: []u8 => tok,
+			};
+			defer free(tok);
+
+			if (strings::fromutf8(tok) == name) {
+				return addr;
+			};
+		};
+	};
+};