(setup_coding_system): Initialize

coding->spec.ccl.eight_bit_carryover.
(ccl_coding_driver): Pay attention to carried over 8-bit bytes.

1 files changed, 56 insertions, 2 deletions

diff --git a/src/coding.c b/src/coding.c
index ade20141c57..854e2b004b4 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -3710,6 +3710,7 @@ setup_coding_system (coding_system, coding)
       }
       coding->common_flags |= CODING_REQUIRE_FLUSHING_MASK;
       coding->spec.ccl.cr_carryover = 0;
+      coding->spec.ccl.eight_bit_carryover[0] = 0;
       break;
 
     case 5:
@@ -4422,6 +4423,7 @@ ccl_coding_driver (coding, source, destination, src_bytes, dst_bytes, encodep)
   struct ccl_program *ccl
     = encodep ? &coding->spec.ccl.encoder : &coding->spec.ccl.decoder;
   int result;
+  unsigned char *dst = destination;
 
   ccl->last_block = coding->mode & CODING_MODE_LAST_BLOCK;
   if (encodep)
@@ -4434,8 +4436,21 @@ ccl_coding_driver (coding, source, destination, src_bytes, dst_bytes, encodep)
       ccl->cr_consumed = coding->spec.ccl.cr_carryover;
     }
   ccl->multibyte = coding->src_multibyte;
-  coding->produced = ccl_driver (ccl, source, destination,
-                                 src_bytes, dst_bytes, &(coding->consumed));
+  if (coding->spec.ccl.eight_bit_carryover[0] != 0)
+    {
+      /* Move carryover bytes to DESTINATION.  */
+      unsigned char *p = coding->spec.ccl.eight_bit_carryover;
+      while (*p)
+        *dst++ = *p++;
+      coding->spec.ccl.eight_bit_carryover[0] = 0;
+      if (dst_bytes)
+        dst_bytes -= dst - destination;
+    }
+
+  coding->produced = (ccl_driver (ccl, source, dst, src_bytes, dst_bytes,
+                                  &(coding->consumed))
+                      + dst - destination);
+
   if (encodep)
     {
       coding->produced_char = coding->produced;
@@ -4443,8 +4458,47 @@ ccl_coding_driver (coding, source, destination, src_bytes, dst_bytes, encodep)
     }
   else
     {
+      /* On decoding, the destination should always multibyte.  But,
+         CCL program might have been generated an invalid multibyte
+         sequence.  Here we make such a sequence valid as
+         multibyte.  */
       int bytes
         = dst_bytes ? dst_bytes : source + coding->consumed - destination;
+
+      if ((coding->consumed < src_bytes
+           || !ccl->last_block)
+          && coding->produced >= 1
+          && destination[coding->produced - 1] >= 0x80)
+        {
+          /* We should not convert the tailing 8-bit codes to
+             multibyte form even if they doesn't form a valid
+             multibyte sequence.  They may form a valid sequence in
+             the next call.  */
+          int carryover = 0;
+
+          if (destination[coding->produced - 1] < 0xA0)
+            carryover = 1;
+          else if (coding->produced >= 2)
+            {
+              if (destination[coding->produced - 2] >= 0x80)
+                {
+                  if (destination[coding->produced - 2] < 0xA0)
+                    carryover = 2;
+                  else if (coding->produced >= 3
+                           && destination[coding->produced - 3] >= 0x80
+                           && destination[coding->produced - 3] < 0xA0)
+                    carryover = 3;
+                }
+            }
+          if (carryover > 0)
+            {
+              BCOPY_SHORT (destination + coding->produced - carryover,
+                           coding->spec.ccl.eight_bit_carryover,
+                           carryover);
+              coding->spec.ccl.eight_bit_carryover[carryover] = 0;
+              coding->produced -= carryover;
+            }
+        }
       coding->produced = str_as_multibyte (destination, bytes,
                                            coding->produced,
                                            &(coding->produced_char));