From: Guus Sliepen <guus@meshlink.io>
Date: Sun, 11 Oct 2015 11:32:55 +0000 (+0200)
Subject: Use '== -1' to check for errors from functions.
X-Git-Url: http://git.meshlink.io/?p=utcp;a=commitdiff_plain;h=9c93346a7b4a539d111a2ebb1a95d70b394bc7f4

Use '== -1' to check for errors from functions.

As made obvious by commit 123f53f, the type of ssize_t cannot be trusted
on Windows to actually be signed, so don't use '< 0', as the compiler
will optimize the test away. POSIX also specifies only that -1 signals
an error condition, not any other negative value.

Luckily, comparing an unsigned int to -1 still works as intended.
---

diff --git a/selftest.c b/selftest.c
index f6e4c8c..8abf4cc 100644
--- a/selftest.c
+++ b/selftest.c
@@ -82,7 +82,7 @@ int main(int argc, char *argv[]) {
 	ssize_t len = utcp_send(c, "Hello world!\n", 13);
 
 	if(len != 13) {
-		if(len < 0)
+		if(len == -1)
 			fprintf(stderr, "Error: %s\n", strerror(errno));
 		else
 			fprintf(stderr, "Short write %zd!\n", len);
@@ -90,7 +90,7 @@ int main(int argc, char *argv[]) {
 	len = utcp_send(c, "This is a test.\n", 16);
 
 	if(len != 16) {
-		if(len < 0)
+		if(len == -1)
 			fprintf(stderr, "Error: %s\n", strerror(errno));
 		else
 			fprintf(stderr, "Short write %zd!\n", len);
diff --git a/test.c b/test.c
index b5d64a3..75fce79 100644
--- a/test.c
+++ b/test.c
@@ -73,7 +73,7 @@ int main(int argc, char *argv[]) {
 		return 1;
 
 	int s = socket(ai->ai_family, ai->ai_socktype, ai->ai_protocol);
-	if(s < 0)
+	if(s == -1)
 		return 1;
 
 	if(server) {
@@ -124,7 +124,7 @@ int main(int argc, char *argv[]) {
 				dir &= ~1;
 				if(c)
 					utcp_shutdown(c, SHUT_WR);
-				if(len < 0)
+				if(len == -1)
 					break;
 				else
 					continue;