win32_writev(): Improve writev emulation

[wimlib] / src / win32.c

diff --git a/src/win32.c b/src/win32.c
index 789eacce6c5adf6dbbb7ddfd5f862053ed894be5..84923753be24faf409ac30a718ccc875adeb590c 100644 (file)
--- a/src/win32.c
+++ b/src/win32.c
@@ -3040,14 +3040,23 @@ win32_pwrite(int fd, const void *buf, size_t count, off_t offset)
 extern ssize_t
 win32_writev(int fd, const struct iovec *iov, int iovcnt)
 {
-       size_t total_bytes_written = 0;
-       for (int i = 0; i < iovcnt; i++) {
-               size_t bytes_written;
+       ssize_t total_bytes_written = 0;
 
-               bytes_written = full_write(fd, iov[i].iov_base, iov[i].iov_len);
-               total_bytes_written += bytes_written;
-               if (bytes_written != iov[i].iov_len)
+       if (iovcnt <= 0) {
+               errno = EINVAL;
+               return -1;
+       }
+       for (int i = 0; i < iovcnt; i++) {
+               ssize_t bytes_written;
+
+               bytes_written = write(fd, iov[i].iov_base, iov[i].iov_len);
+               if (bytes_written >= 0)
+                       total_bytes_written += bytes_written;
+               if (bytes_written != iov[i].iov_len) {
+                       if (total_bytes_written == 0)
+                               total_bytes_written = -1;
                        break;
+               }
        }
        return total_bytes_written;
 }