From: Guus Sliepen <guus@sliepen.org>
Date: Thu, 8 Aug 2019 13:14:09 +0000 (+0200)
Subject: Add a flag to prevent partial writes on a UTCP connection.
X-Git-Url: https://git.meshlink.io/?a=commitdiff_plain;h=3bc564058072a79a22320f8c5bc50e8844896114;p=utcp

Add a flag to prevent partial writes on a UTCP connection.
---

diff --git a/utcp.c b/utcp.c
index d837d27..5938ea5 100644
--- a/utcp.c
+++ b/utcp.c
@@ -611,6 +611,20 @@ ssize_t utcp_send(struct utcp_connection *c, const void *data, size_t len) {
 		return -1;
 	}
 
+	// Check if we need to be able to buffer all data
+
+	if(c->flags & UTCP_NO_PARTIAL) {
+		if(len > buffer_free(&c->sndbuf)) {
+			if(len > c->sndbuf.maxsize) {
+				errno = EMSGSIZE;
+				return -1;
+			} else {
+				errno = EWOULDBLOCK;
+				return 0;
+			}
+		}
+	}
+
 	// Add data to send buffer.
 
 	len = buffer_put(&c->sndbuf, data, len);
diff --git a/utcp.h b/utcp.h
index 4b7075b..c570b32 100644
--- a/utcp.h
+++ b/utcp.h
@@ -49,6 +49,7 @@ struct utcp_connection;
 #define UTCP_RELIABLE 2
 #define UTCP_FRAMED 4
 #define UTCP_DROP_LATE 8
+#define UTCP_NO_PARTIAL 16
 
 #define UTCP_TCP 3
 #define UTCP_UDP 0