xread/write can use full_read/write (smaller code)

3 files changed, 8 insertions, 12 deletions

diff --git a/libbb/full_read.c b/libbb/full_read.c
index b5837d5bd..068d16698 100644
--- a/libbb/full_read.c
+++ b/libbb/full_read.c
@@ -24,7 +24,7 @@ ssize_t full_read(int fd, void *buf, size_t len)
 
 	total = 0;
 
-	while (len > 0) {
+	while (len) {
 		cc = safe_read(fd, buf, len);
 
 		if (cc < 0)
diff --git a/libbb/full_write.c b/libbb/full_write.c
index d812d04b4..563f4a851 100644
--- a/libbb/full_write.c
+++ b/libbb/full_write.c
@@ -23,7 +23,7 @@ ssize_t full_write(int fd, const void *buf, size_t len)
 
 	total = 0;
 
-	while (len > 0) {
+	while (len) {
 		cc = safe_write(fd, buf, len);
 
 		if (cc < 0)
diff --git a/libbb/xfuncs.c b/libbb/xfuncs.c
index d22cd279a..efc919491 100644
--- a/libbb/xfuncs.c
+++ b/libbb/xfuncs.c
@@ -113,24 +113,20 @@ int xopen3(const char *pathname, int flags, int mode)
 // Die with an error message if we can't read the entire buffer.
 void xread(int fd, void *buf, size_t count)
 {
-	while (count) {
-		ssize_t size = safe_read(fd, buf, count);
-		if (size < 1)
+	if (count) {
+		ssize_t size = full_read(fd, buf, count);
+		if (size != count)
 			bb_error_msg_and_die("short read");
-		count -= size;
-		buf = ((char *) buf) + size;
 	}
 }
 
 // Die with an error message if we can't write the entire buffer.
 void xwrite(int fd, void *buf, size_t count)
 {
-	while (count) {
-		ssize_t size = safe_write(fd, buf, count);
-		if (size < 1)
+	if (count) {
+		ssize_t size = full_write(fd, buf, count);
+		if (size != count)
 			bb_error_msg_and_die("short write");
-		count -= size;
-		buf = ((char *) buf) + size;
 	}
 }