hare

commit 842b4d0edcea4006eef3ec0177c08dbb9e319fc2
parent 088579531180231b851b7e0db2392d542a8a10f1
Author: Bor Grošelj Simić <bgs@turminal.net>
Date:   Fri, 27 May 2022 23:09:35 +0200

encoding::pem: fix an issue with short writes

Signed-off-by: Bor Grošelj Simić <bgs@turminal.net>

Diffstat:
M
encoding/pem/+test.ha
 | 
10
++++++++++
M
encoding/pem/pem.ha
 | 
17
++++++++++++++++-

2 files changed, 26 insertions(+), 1 deletion(-)
diff --git a/encoding/pem/+test.ha b/encoding/pem/+test.ha
@@ -61,6 +61,16 @@ use strio;
 	io::close(&stream)!;
 	assert(strio::string(&out) == privkey_str);
 	io::close(&out)!;
+
+	// test short writes
+	let out = strio::dynamic();
+	const stream = newencoder("CERTIFICATE", &out)!;
+	for (let i = 0z; i < len(testcert_bin); i += 1) {
+		io::write(&stream, [testcert_bin[i]])!;
+	};
+	io::close(&stream)!;
+	assert(strio::string(&out) == cert_str);
+	io::close(&out)!;
 };
 
 const cert_str: str =
diff --git a/encoding/pem/pem.ha b/encoding/pem/pem.ha
@@ -202,6 +202,8 @@ export type pemencoder = struct {
 	out: io::handle,
 	b64: base64::encoder,
 	label: str,
+	buf: [48]u8,
+	ln: u8,
 };
 
 const pemencoder_vt: io::vtable = io::vtable {
@@ -219,22 +221,35 @@ export fn newencoder(label: str, s: io::handle) (pemencoder | io::error) = {
 		out = s,
 		b64 = base64::newencoder(&base64::std_encoding, s),
 		label = label,
+		...
 	};
 };
 
 fn pem_write(s: *io::stream, buf: const []u8) (size | io::error) = {
 	let s = s: *pemencoder;
 	let buf = buf: []u8;
+	if (len(buf) < len(s.buf) - s.ln) {
+		s.buf[s.ln..s.ln+len(buf)] = buf[..];
+		s.ln += len(buf): u8;
+		return len(buf);
+	};
 	let z = 0z;
+	s.buf[s.ln..] = buf[..len(s.buf) - s.ln];
+	z += io::writeall(&s.b64, s.buf)?;
+	z += io::write(s.out, ['\n'])?;
+	buf = buf[len(s.buf) - s.ln..];
 	for (len(buf) >= 48; buf = buf[48..]) {
 		z += io::writeall(&s.b64, buf[..48])?;
 		z += io::write(s.out, ['\n'])?;
 	};
-	return z + io::writeall(&s.b64, buf)?;
+	s.ln = len(buf): u8;
+	s.buf[..s.ln] = buf;
+	return z + s.ln;
 };
 
 fn pem_wclose(s: *io::stream) (void | io::error) = {
 	let s = s: *pemencoder;
+	io::writeall(&s.b64, s.buf[..s.ln])?;
 	io::close(&s.b64)?;
 	fmt::fprintf(s.out, "\n{}{}{}\n", end, s.label, suffix)?;
 };