[PATCH] Add support for sending small data through obex

[PATCH] Add support for sending small data through obex

[Radoslaw Jablonski]

Added handling packets smaller than mtu in obex_write_stream. Now trying
to read from source until mtu will be filled properly and not sending
immediately data if it is smaller than mtu.
---
 src/obex.c |   48 +++++++++++++++++++++++++++++++++++++-----------
 1 files changed, 37 insertions(+), 11 deletions(-)

diff --git a/src/obex.c b/src/obex.c
index 6d4430d..d3a6ccd 100644
--- a/src/obex.c
+++ b/src/obex.c
@@ -623,6 +623,7 @@ static int obex_write_stream(struct obex_session *os,
 	obex_headerdata_t hd;
 	uint8_t *ptr;
 	ssize_t len;
+	ssize_t r_len;
 	unsigned int flags;
 	uint8_t hi;
 
@@ -642,18 +643,37 @@ static int obex_write_stream(struct obex_session *os,
 		goto add_header;
 	}
 
-	len = os->driver->read(os->object, os->buf, os->tx_mtu, &hi);
-	if (len < 0) {
-		error("read(): %s (%zd)", strerror(-len), -len);
-		if (len == -EAGAIN)
-			return len;
-		else if (len == -ENOSTR)
-			return 0;
+	/* Copying data from source until we reach end of the stream. Sending
+	 * data only if MTU will be filled in 100% or we reach end of data.
+	 * Remaining data in buffer will be sent with next amount of data
+	 * from source.*/
+	do {
+		r_len = os->driver->read(os->object, os->buf + os->pending,
+					os->tx_mtu - os->pending, &hi);
+
+		if (r_len < 0) {
+			error("read(): %s (%zd)", strerror(-r_len), -r_len);
+
+			switch(r_len) {
+			case -EAGAIN:
+				return r_len;
+			case -EINTR:
+				continue;
+			case -ENOSTR:
+				return 0;
+			default:
+				g_free(os->buf);
+				os->buf = NULL;
+				return r_len;
+			}
+		}
 
-		g_free(os->buf);
-		os->buf = NULL;
-		return len;
-	}
+		/* Saving amount of data accumulated in obex buffer */
+		os->pending += r_len;
+	} while (os->pending < os->tx_mtu && r_len != 0);
+
+	len = os->pending;
+	os->pending = 0;
 
 	ptr = os->buf;
 
@@ -702,6 +722,12 @@ static gboolean handle_async_io(void *object, int flags, int err,
 		ret = obex_read_stream(os, os->obex, os->obj);
 
 proceed:
+
+	/* Returning TRUE to not delete current watcher - it need to be active
+	 * to handle next io flag changes (more data will be available later)*/
+	if (ret == -EAGAIN)
+		return TRUE;
+
 	if (ret < 0) {
 		os_set_response(os->obj, err);
 		OBEX_CancelRequest(os->obex, TRUE);
-- 
1.7.0.4

Re: [PATCH] Add support for sending small data through obex

[Luiz Augusto von Dentz]

Hi,

On Mon, Nov 1, 2010 at 11:24 AM, Radoslaw Jablonski
<ext-jablonski.radoslaw@nokia.com> wrote:
> Added handling packets smaller than mtu in obex_write_stream. Now trying
> to read from source until mtu will be filled properly and not sending
> immediately data if it is smaller than mtu.
> ---
>  src/obex.c |   48 +++++++++++++++++++++++++++++++++++++-----------
>  1 files changed, 37 insertions(+), 11 deletions(-)
>
> diff --git a/src/obex.c b/src/obex.c
> index 6d4430d..d3a6ccd 100644
> --- a/src/obex.c
> +++ b/src/obex.c
> @@ -623,6 +623,7 @@ static int obex_write_stream(struct obex_session *os,
>        obex_headerdata_t hd;
>        uint8_t *ptr;
>        ssize_t len;
> +       ssize_t r_len;

You can have len and r_len in the same line above.

>        unsigned int flags;
>        uint8_t hi;
>
> @@ -642,18 +643,37 @@ static int obex_write_stream(struct obex_session *os,
>                goto add_header;
>        }
>
> -       len = os->driver->read(os->object, os->buf, os->tx_mtu, &hi);
> -       if (len < 0) {
> -               error("read(): %s (%zd)", strerror(-len), -len);
> -               if (len == -EAGAIN)
> -                       return len;
> -               else if (len == -ENOSTR)
> -                       return 0;
> +       /* Copying data from source until we reach end of the stream. Sending
> +        * data only if MTU will be filled in 100% or we reach end of data.
> +        * Remaining data in buffer will be sent with next amount of data
> +        * from source.*/
> +       do {
> +               r_len = os->driver->read(os->object, os->buf + os->pending,
> +                                       os->tx_mtu - os->pending, &hi);

It looks like you should add one more tab in the line above it that
doesn't go over 80 columns.

> +               if (r_len < 0) {
> +                       error("read(): %s (%zd)", strerror(-r_len), -r_len);
> +
> +                       switch(r_len) {
> +                       case -EAGAIN:
> +                               return r_len;
> +                       case -EINTR:
> +                               continue;
> +                       case -ENOSTR:
> +                               return 0;
> +                       default:
> +                               g_free(os->buf);
> +                               os->buf = NULL;
> +                               return r_len;
> +                       }
> +               }

I think it is probably more efficiently to handle rlen == 0 here, like
if (rlen == 0) break; else if (rlen < 0)

> -               g_free(os->buf);
> -               os->buf = NULL;
> -               return len;
> -       }
> +               /* Saving amount of data accumulated in obex buffer */
> +               os->pending += r_len;
> +       } while (os->pending < os->tx_mtu && r_len != 0);

That simplify here too, just do while (os->pending < os->txt_mtu) if
you handle rlen == 0 like I said before.

> +
> +       len = os->pending;
> +       os->pending = 0;
>
>        ptr = os->buf;
>
> @@ -702,6 +722,12 @@ static gboolean handle_async_io(void *object, int flags, int err,
>                ret = obex_read_stream(os, os->obex, os->obj);
>
>  proceed:
> +
> +       /* Returning TRUE to not delete current watcher - it need to be active
> +        * to handle next io flag changes (more data will be available later)*/
> +       if (ret == -EAGAIN)
> +               return TRUE;
> +
>        if (ret < 0) {
>                os_set_response(os->obj, err);
>                OBEX_CancelRequest(os->obex, TRUE);
> --
> 1.7.0.4
>
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-- 
Luiz Augusto von Dentz
Computer Engineer