Re: [PATCH v9 10/14] pkt-line: add functions to read/write flush terminated packet streams

On 04 Oct 2016, at 21:53, Junio C Hamano [off-list ref] wrote:

larsxschneider@gmail.com writes:

quoted

From: Lars Schneider <redacted>

quoted

+int write_packetized_from_buf(const char *src_in, size_t len, int fd_out)
+{
+	static char buf[LARGE_PACKET_DATA_MAX];
+	int err = 0;
+	size_t bytes_written = 0;
+	size_t bytes_to_write;
+
+	while (!err) {
+		if ((len - bytes_written) > sizeof(buf))
+			bytes_to_write = sizeof(buf);
+		else
+			bytes_to_write = len - bytes_written;
+		if (bytes_to_write == 0)
+			break;
+		err = packet_write_gently(fd_out, src_in + bytes_written, bytes_to_write);
+		bytes_written += bytes_to_write;
+	}
+	if (!err)
+		err = packet_flush_gently(fd_out);
+	return err;
+}

Hmph, what is buf[] used for, other than its sizeof() taken to yield
a constant LARGE_PACKET_DATA_MAX?

Agreed. This is stupid. I will fix it.

quoted

+	for (;;) {
+		strbuf_grow(sb_out, LARGE_PACKET_DATA_MAX);
+		packet_len = packet_read(fd_in, NULL, NULL,
+			// TODO: explain + 1

No // C99 comment please.

And I agree that the +1 needs to be explained.

Oh. I did not send the very latest version :-(

Is this explanation OK?

+       strbuf_grow(sb_out, LARGE_PACKET_DATA_MAX);
+       packet_len = packet_read(fd_in, NULL, NULL,
+           /* strbuf_grow() above always allocates one extra byte to
+            * store a '\0' at the end of the string. packet_read()
+            * writes a '\0' extra byte at the end, too. Let it know
+            * that there is already room for the extra byte.
+            */
+           sb_out->buf + sb_out->len, LARGE_PACKET_DATA_MAX+1,
+           PACKET_READ_GENTLE_ON_EOF);


Thanks,
Lars