(strout): Convert old echo area to multibyte, like printchar.

(printchar, strout): If echo area text converted to multibyte
does not all fit, truncate it at char boundary.

1 files changed, 37 insertions, 5 deletions

diff --git a/src/print.c b/src/print.c
index dc6272d2f82..8bfefe0508c 100644
--- a/src/print.c
+++ b/src/print.c
@@ -398,11 +398,15 @@ printchar (ch, fun)
                      0, 1);
           printbufidx = size;
           if (printbufidx > FRAME_MESSAGE_BUF_SIZE (mini_frame))
-            printbufidx = FRAME_MESSAGE_BUF_SIZE (mini_frame);
+            {
+              printbufidx = FRAME_MESSAGE_BUF_SIZE (mini_frame);
+              /* Rewind incomplete multi-byte form.  */
+              while (printbufidx > 0 && tembuf[printbufidx] >= 0xA0)
+                printbufidx--;
+            }
           bcopy (tembuf, FRAME_MESSAGE_BUF (mini_frame), printbufidx);
+          message_enable_multibyte = 1;
         }
-      message_enable_multibyte
-        = ! NILP (current_buffer->enable_multibyte_characters);
 
       if (printbufidx < FRAME_MESSAGE_BUF_SIZE (mini_frame) - len)
         bcopy (str, &FRAME_MESSAGE_BUF (mini_frame)[printbufidx], len),
@@ -489,16 +493,44 @@ strout (ptr, size, size_byte, printcharfun, multibyte)
         }
 
       message_dolog (ptr, size_byte, 0, multibyte);
+
+      /* Convert message to multibyte if we are now adding multibyte text.  */
+      if (multibyte
+          && ! message_enable_multibyte
+          && printbufidx > 0)
+        {
+          int size = count_size_as_multibyte (FRAME_MESSAGE_BUF (mini_frame),
+                                              printbufidx);
+          unsigned char *tembuf = (unsigned char *) alloca (size + 1);
+          copy_text (FRAME_MESSAGE_BUF (mini_frame), tembuf, printbufidx,
+                     0, 1);
+          printbufidx = size;
+          if (printbufidx > FRAME_MESSAGE_BUF_SIZE (mini_frame))
+            {
+              printbufidx = FRAME_MESSAGE_BUF_SIZE (mini_frame);
+              /* Rewind incomplete multi-byte form.  */
+              while (printbufidx > 0 && tembuf[printbufidx] >= 0xA0)
+                printbufidx--;
+            }
+
+          bcopy (tembuf, FRAME_MESSAGE_BUF (mini_frame), printbufidx);
+          message_enable_multibyte = 1;
+        }
+
+      /* Compute how much of the new text will fit there.  */
       if (size_byte > FRAME_MESSAGE_BUF_SIZE (mini_frame) - printbufidx - 1)
         {
           size_byte = FRAME_MESSAGE_BUF_SIZE (mini_frame) - printbufidx - 1;
           /* Rewind incomplete multi-byte form.  */
-          while (size_byte && (unsigned char) ptr[size] >= 0xA0) size--;
+          while (size_byte && (unsigned char) ptr[size_byte] >= 0xA0)
+            size_byte--;
         }
+
+      /* Put that part of the new text in.  */
       bcopy (ptr, &FRAME_MESSAGE_BUF (mini_frame) [printbufidx], size_byte);
       printbufidx += size_byte;
-      echo_area_glyphs_length = printbufidx;
       FRAME_MESSAGE_BUF (mini_frame) [printbufidx] = 0;
+      echo_area_glyphs_length = printbufidx;
 
       return;
     }