Allow short reads from read_func

1 files changed, 9 insertions, 14 deletions

diff --git a/examples/all_functions.c b/examples/all_functions.c
index 413d114..ee960b3 100644
--- a/examples/all_functions.c
+++ b/examples/all_functions.c
@@ -10,21 +10,16 @@
 
 static size_t custom_read(void *udata, char *buf, size_t size) {
 	int fd = (int)(intptr_t)udata;
-	size_t total_read = 0;
-	while (true) {
-		// must call read in a loop to fill buf up as much as possible!
-		// (read isn't guaranteed to read len bytes even if it could)
-		ssize_t ret = read(fd, buf, size);
-		if (ret <= 0) {
-			// read error/end-of-file
-			break;
-		} else {
-			total_read += ret;
-			buf += ret;
-			size -= ret;
-		}
+	// only read up to 4 bytes at a time. why not!
+	// it's much slower, but it is allowed.
+	ssize_t ret = read(fd, buf, size < 4 ? size : 4);
+	if (ret < 0) {
+		// read error occured.
+		// we could store an error away somewhere if we wanted to
+		// (read errors are unusual anyways.)
+		ret = 0;
 	}
-	return total_read;
+	return ret;
 }
 
 int main(void) {