(encode_coding_iso2022): Write out invalid multibyte

forms in a buffer as is.
(detect_coding_mask): If ISO_CODE_CSI appears in an invalid
sequence, ignore it.

diff --git a/src/coding.c b/src/coding.c
index bd824bceee2ff90e65afb8621c0af373636c6c27..2ebf0a2eade050406483e50c6f7858f21e03b3fc 100644 (file)
--- a/src/coding.c
+++ b/src/coding.c
@@ -1495,12 +1495,26 @@ encode_coding_iso2022 (coding, source, destination,
 
        case EMACS_leading_code_2:
          ONE_MORE_BYTE (c2);
-         ENCODE_ISO_CHARACTER (c1, c2, /* dummy */ c3);
+         if (c2 < 0xA0)
+           {
+             /* invalid sequence */
+             *dst++ = c1;
+             *dst++ = c2;
+           }
+         else
+           ENCODE_ISO_CHARACTER (c1, c2, /* dummy */ c3);
          break;
 
        case EMACS_leading_code_3:
          TWO_MORE_BYTES (c2, c3);
-         if (c1 < LEADING_CODE_PRIVATE_11)
+         if (c2 < 0xA0 || c3 < 0xA0)
+           {
+             /* invalid sequence */
+             *dst++ = c1;
+             *dst++ = c2;
+             *dst++ = c3;
+           }
+         else if (c1 < LEADING_CODE_PRIVATE_11)
            ENCODE_ISO_CHARACTER (c1, c2, c3);
          else
            ENCODE_ISO_CHARACTER (c2, c3, /* dummy */ c4);
@@ -1508,12 +1522,27 @@ encode_coding_iso2022 (coding, source, destination,
 
        case EMACS_leading_code_4:
          THREE_MORE_BYTES (c2, c3, c4);
-         ENCODE_ISO_CHARACTER (c2, c3, c4);
+         if (c2 < 0xA0 || c3 < 0xA0 || c4 < 0xA0)
+           {
+             /* invalid sequence */
+             *dst++ = c1;
+             *dst++ = c2;
+             *dst++ = c3;
+             *dst++ = c4;
+           }
+         else
+           ENCODE_ISO_CHARACTER (c2, c3, c4);
          break;
 
        case EMACS_leading_code_composition:
-         ONE_MORE_BYTE (c1);
-         if (c1 == 0xFF)
+         ONE_MORE_BYTE (c2);
+         if (c2 < 0xA0)
+           {
+             /* invalid sequence */
+             *dst++ = c1;
+             *dst++ = c2;
+           }
+         else if (c2 == 0xFF)
            {
              coding->composing = COMPOSING_WITH_RULE_HEAD;
              ENCODE_COMPOSITION_WITH_RULE_START;
@@ -2555,7 +2584,7 @@ detect_coding_mask (src, src_bytes)
        /* No valid ISO2022 code follows C.  Try again.  */
        goto label_loop_detect_coding;
     }
-  else if (c == ISO_CODE_SS2 || c == ISO_CODE_SS3 || c == ISO_CODE_CSI)
+  else if (c == ISO_CODE_SS2 || c == ISO_CODE_SS3)
     /* C is an ISO2022 specific control code of C1,
        or the first byte of SJIS's 2-byte character code,
        or a leading code of Emacs.  */
@@ -2563,6 +2592,17 @@ detect_coding_mask (src, src_bytes)
            | detect_coding_sjis (src, src_end)
            | detect_coding_emacs_mule (src, src_end));
 
+  else if (c == ISO_CODE_CSI
+          && (src < src_end
+             && (*src == ']'
+                 || (src + 1 < src_end
+                     && src[1] == ']'
+                     && (*src == '0' || *src == '1' || *src == '2')))))
+    /* C is an ISO2022's control-sequence-introducer.  */
+    mask = (detect_coding_iso2022 (src, src_end)
+           | detect_coding_sjis (src, src_end)
+           | detect_coding_emacs_mule (src, src_end));
+    
   else if (c < 0xA0)
     /* C is the first byte of SJIS character code,
        or a leading-code of Emacs.  */