Improve error checking in stream writing functions.

* libmailutils/stream/stream.c (mu_stream_write): Return EIO on
short writes if pnwritten is NULL.
* libmailutils/stream/streamcpy.c (mu_stream_copy): Likewise (if
source stream size is known.

2 files changed, 27 insertions, 21 deletions

diff --git a/libmailutils/stream/stream.c b/libmailutils/stream/stream.c
index de995aa57..8c9cbb6e0 100644
--- a/libmailutils/stream/stream.c
+++ b/libmailutils/stream/stream.c
@@ -1027,12 +1027,17 @@ mu_stream_write (mu_stream_t stream, const void *buf, size_t size,
 	  bufp += n;
 	  size -= n;
 	  _stream_setflag (stream, _MU_STR_DIRTY);
 	}
       if (pnwritten)
 	*pnwritten = nbytes;
+      else if (nbytes < size)
+	{
+	  rc = EIO;
+	  mu_stream_seterr (stream, rc, 1);
+	}
     }
   return rc;
 }
 
 int
 mu_stream_writeline (mu_stream_t stream, const char *buf, size_t size)
diff --git a/libmailutils/stream/streamcpy.c b/libmailutils/stream/streamcpy.c
index 3270ee9fb..aaf0e7273 100644
--- a/libmailutils/stream/streamcpy.c
+++ b/libmailutils/stream/streamcpy.c
@@ -35,13 +35,13 @@ mu_stream_copy (mu_stream_t dst, mu_stream_t src, mu_off_t size,
 		mu_off_t *pcsz)
 {
   int status;
   size_t bufsize, n;
   char *buf;
   mu_off_t total = 0;
-  
+
   if (pcsz)
     *pcsz = 0;
   if (size == 0)
     {
       status = mu_stream_size (src, &size);
       switch (status)
@@ -53,25 +53,25 @@ mu_stream_copy (mu_stream_t dst, mu_stream_t src, mu_off_t size,
 	  size = 0;
 	  break;
 
 	default:
 	  return status;
 	}
-      
+
       if (size)
 	{
 	  mu_off_t pos;
 	  status = mu_stream_seek (src, 0, MU_SEEK_CUR, &pos);
 	  switch (status)
 	    {
 	    case 0:
 	      if (pos > size)
 		return ESPIPE;
 	      size -= pos;
 	      break;
-      
+
 	    case EACCES:
 	      mu_stream_clearerr (src);
 	    case ENOSYS:
 	      size = 0;
 	      break;
 
@@ -87,27 +87,32 @@ mu_stream_copy (mu_stream_t dst, mu_stream_t src, mu_off_t size,
 
   for (; (buf = malloc (bufsize)) == NULL; bufsize >>= 1)
     if (bufsize < STREAMCPY_MIN_BUF_SIZE)
       return ENOMEM;
 
   if (size)
-    while (size)
-      {
-	size_t rdsize = bufsize < size ? bufsize : size;
+    {
+      while (size)
+	{
+	  size_t rdsize = bufsize < size ? bufsize : size;
 
-	status = mu_stream_read (src, buf, rdsize, &n);
-	if (status)
-	  break;
-	if (n == 0)
-	  break;
-	status = mu_stream_write (dst, buf, n, NULL);
-	if (status)
-	  break;
-	size -= n;
-	total += n;
-      }
+	  status = mu_stream_read (src, buf, rdsize, &n);
+	  if (status)
+	    break;
+	  if (n == 0)
+	    break;
+	  status = mu_stream_write (dst, buf, n, NULL);
+	  if (status)
+	    break;
+	  size -= n;
+	  total += n;
+	}
+
+      if (!pcsz && size)
+	status = EIO;
+    }
   else
     while ((status = mu_stream_read (src, buf, bufsize, &n)) == 0
 	   && n > 0)
       {
 	status = mu_stream_write (dst, buf, n, NULL);
 	if (status)
@@ -121,10 +126,6 @@ mu_stream_copy (mu_stream_t dst, mu_stream_t src, mu_off_t size,
   else if (total == 0)
     status = EOF;
   */
   free (buf);
   return status;
 }
-      
-
-  
-