[PATCH u-boot-marvell 04/29] tools: kwboot: Refactor and fix writing buffer

[Marek Behún]

There are 3 instances in kwboot.c where we need to write() a given
buffer whole (iteratively writing until all data are written), and 2 of
those instances are wrong, for they do not increment the buffer pointer.

Refactor the code into a new function kwboot_write() where it is fixed.

Signed-off-by: Marek Behún <marek.be...@nic.cz>
---
 tools/kwboot.c | 55 ++++++++++++++++++++++++--------------------------
 1 file changed, 26 insertions(+), 29 deletions(-)

diff --git a/tools/kwboot.c b/tools/kwboot.c
index f18f6d2134..22cdd137ad 100644
--- a/tools/kwboot.c
+++ b/tools/kwboot.c
@@ -72,6 +72,23 @@ static int msg_req_delay = KWBOOT_MSG_REQ_DELAY;
 static int msg_rsp_timeo = KWBOOT_MSG_RSP_TIMEO;
 static int blk_rsp_timeo = KWBOOT_BLK_RSP_TIMEO;
 
+static ssize_t
+kwboot_write(int fd, const char *buf, size_t len)
+{
+       size_t tot = 0;
+
+       while (tot < len) {
+               ssize_t wr = write(fd, buf + tot, len - tot);
+
+               if (wr < 0)
+                       return -1;
+
+               tot += wr;
+       }
+
+       return tot;
+}
+
 static void
 kwboot_printv(const char *fmt, ...)
 {
@@ -191,26 +208,13 @@ out:
 static int
 kwboot_tty_send(int fd, const void *buf, size_t len)
 {
-       int rc;
-       ssize_t n;
-
        if (!buf)
                return 0;
 
-       rc = -1;
-
-       do {
-               n = write(fd, buf, len);
-               if (n < 0)
-                       goto out;
-
-               buf = (char *)buf + n;
-               len -= n;
-       } while (len > 0);
+       if (kwboot_write(fd, buf, len) < 0)
+               return -1;
 
-       rc = tcdrain(fd);
-out:
-       return rc;
+       return tcdrain(fd);
 }
 
 static int
@@ -462,7 +466,7 @@ can:
 static int
 kwboot_term_pipe(int in, int out, const char *quit, int *s)
 {
-       ssize_t nin, nout;
+       ssize_t nin;
        char _buf[128], *buf = _buf;
 
        nin = read(in, buf, sizeof(_buf));
@@ -480,22 +484,15 @@ kwboot_term_pipe(int in, int out, const char *quit, int 
*s)
                                buf++;
                                nin--;
                        } else {
-                               while (*s > 0) {
-                                       nout = write(out, quit, *s);
-                                       if (nout <= 0)
-                                               return -1;
-                                       (*s) -= nout;
-                               }
+                               if (kwboot_write(out, quit, *s) < 0)
+                                       return -1;
+                               *s = 0;
                        }
                }
        }
 
-       while (nin > 0) {
-               nout = write(out, buf, nin);
-               if (nout <= 0)
-                       return -1;
-               nin -= nout;
-       }
+       if (kwboot_write(out, buf, nin) < 0)
+               return -1;
 
        return 0;
 }
-- 
2.31.1