From: Guus Sliepen <guus@meshlink.io>
Date: Thu, 8 Aug 2019 13:20:42 +0000 (+0200)
Subject: Add the MESHLINK_CHANNEL_NO_PARTIAL flag.
X-Git-Url: http://git.meshlink.io/?p=meshlink;a=commitdiff_plain;h=3e675d73bc4d524a0a68a1ec782fe7e3960af398

Add the MESHLINK_CHANNEL_NO_PARTIAL flag.

This ensures that calls to meshlink_channel_send() either succeed with all
data sent, or no data sent at all.
---

diff --git a/src/meshlink++.h b/src/meshlink++.h
index 8287e038..2dcac002 100644
--- a/src/meshlink++.h
+++ b/src/meshlink++.h
@@ -113,6 +113,7 @@ public:
 	static const uint32_t ORDERED = MESHLINK_CHANNEL_ORDERED;
 	static const uint32_t FRAMED = MESHLINK_CHANNEL_FRAMED;
 	static const uint32_t DROP_LATE = MESHLINK_CHANNEL_DROP_LATE;
+	static const uint32_t NO_PARTIAL = MESHLINK_CHANNEL_NO_PARTIAL;
 	static const uint32_t TCP = MESHLINK_CHANNEL_TCP;
 	static const uint32_t UDP = MESHLINK_CHANNEL_UDP;
 };
@@ -714,6 +715,8 @@ public:
 	 *  @param len          The length of the data.
 	 *
 	 *  @return             The amount of data that was queued, which can be less than len, or a negative value in case of an error.
+	 *                      If MESHLINK_CHANNEL_NO_PARTIAL is set, then the result will either be len,
+	 *                      0 if the buffer is currently too full, or -1 if len is too big even for an empty buffer.
 	 */
 	ssize_t channel_send(channel *channel, void *data, size_t len) {
 		return meshlink_channel_send(handle, channel, data, len);
diff --git a/src/meshlink.h b/src/meshlink.h
index 6a1c758a..40deb5f1 100644
--- a/src/meshlink.h
+++ b/src/meshlink.h
@@ -94,6 +94,7 @@ static const uint32_t MESHLINK_CHANNEL_RELIABLE = 1;   // Data is retransmitted
 static const uint32_t MESHLINK_CHANNEL_ORDERED = 2;    // Data is delivered in-order to the application.
 static const uint32_t MESHLINK_CHANNEL_FRAMED = 4;     // Data is delivered in chunks of the same length as data was originally sent.
 static const uint32_t MESHLINK_CHANNEL_DROP_LATE = 8;  // When packets are reordered, late packets are ignored.
+static const uint32_t MESHLINK_CHANNEL_NO_PARTIAL = 16; // Calls to meshlink_channel_send() will either send all data or nothing.
 static const uint32_t MESHLINK_CHANNEL_TCP = 3;        // Select TCP semantics.
 static const uint32_t MESHLINK_CHANNEL_UDP = 0;        // Select UDP semantics.
 
@@ -1119,6 +1120,8 @@ extern void meshlink_channel_close(meshlink_handle_t *mesh, meshlink_channel_t *
  *  @param len          The length of the data, or 0 if there is no data to send.
  *
  *  @return             The amount of data that was queued, which can be less than len, or a negative value in case of an error.
+ *                      If MESHLINK_CHANNEL_NO_PARTIAL is set, then the result will either be len,
+ *                      0 if the buffer is currently too full, or -1 if len is too big even for an empty buffer.
  */
 extern ssize_t meshlink_channel_send(meshlink_handle_t *mesh, meshlink_channel_t *channel, const void *data, size_t len);
 
diff --git a/src/utcp b/src/utcp
index fa93ca75..3bc56405 160000
--- a/src/utcp
+++ b/src/utcp
@@ -1 +1 @@
-Subproject commit fa93ca75a603758e00781f2e9acb52bdbe6695b7
+Subproject commit 3bc564058072a79a22320f8c5bc50e8844896114