(DECODE_COMPOSITION_START): If the source is short, set

coding->result to CODING_RESULT_INSUFFICIENT_SRC.
(decode_coding_gap): Set CODING_MODE_LAST_BLOCK after the call of
detect_coding.
(emacs_mule_char): Handle old style (Emacs 20) component character
of a composition.
(DECODE_EMACS_MULE_COMPOSITION_RULE_20): Fix parsing a composition
rule.
(DECODE_EMACS_MULE_20_RULEBASE_COMPOSITION): Likewise.
(decode_coding_emacs_mule): Handle invalid bytes correctly.

1 files changed, 25 insertions, 6 deletions

diff --git a/src/coding.c b/src/coding.c
index 5d92b7803c1..05d2a06843b 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -1702,6 +1702,18 @@ emacs_mule_char (coding, src, nbytes, nchars, id)
     }
   else
     {
+      if (c >= 0xA0)
+        {
+          /* Old style component character of a compostion.  */
+          if (c == 0xA0)
+            {
+              ONE_MORE_BYTE (c);
+              c -= 0x80;
+            }
+          else
+            c -= 0x20;
+        }
+
       switch (emacs_mule_bytes[c])
         {
         case 2:
@@ -1912,7 +1924,7 @@ detect_coding_emacs_mule (coding, detect_info)
     if (src >= src_end)                                 \
       goto invalid_code;                                \
     ONE_MORE_BYTE_NO_CHECK (c);                         \
-    c -= 0x20;                                          \
+    c -= 0xA0;                                          \
     if (c < 0 || c >= 81)                               \
       goto invalid_code;                                \
                                                         \
@@ -2010,23 +2022,28 @@ detect_coding_emacs_mule (coding, detect_info)
     /* Emacs 20 style format for rule-base composition.  */     \
     /* Store multibyte form of characters to be composed.  */   \
     enum composition_method method = COMPOSITION_WITH_RULE;     \
+    int *charbuf_base = charbuf;                                \
     int components[MAX_COMPOSITION_COMPONENTS * 2 - 1];         \
     int *buf = components;                                      \
     int i, j;                                                   \
-                                                                \
+                                                                \
     DECODE_EMACS_MULE_COMPOSITION_CHAR (buf);                   \
-    for (i = 0; i < MAX_COMPOSITION_COMPONENTS; i++)            \
+    for (i = 1; i < MAX_COMPOSITION_COMPONENTS; i++)            \
       {                                                         \
+        if (*src < 0xA0)                                        \
+          break;                                                \
         DECODE_EMACS_MULE_COMPOSITION_RULE_20 (buf);            \
         DECODE_EMACS_MULE_COMPOSITION_CHAR (buf);               \
       }                                                         \
-    if (i < 1 || (buf - components) % 2 == 0)                   \
+    if (i <= 1 || (buf - components) % 2 == 0)                  \
       goto invalid_code;                                        \
-    if (charbuf + i + (i / 2) + 1 < charbuf_end)                \
+    if (charbuf + i + (i / 2) + 1 >= charbuf_end)               \
       goto no_more_source;                                      \
-    ADD_COMPOSITION_DATA (buf, i, method);                      \
+    ADD_COMPOSITION_DATA (charbuf, i, method);                  \
+    i = i * 2 - 1;                                              \
     for (j = 0; j < i; j++)                                     \
       *charbuf++ = components[j];                               \
+    charbuf_base[0] -= i;                                       \
     for (j = 0; j < i; j += 2)                                  \
       *charbuf++ = components[j];                               \
   } while (0)
@@ -2113,6 +2130,8 @@ decode_coding_emacs_mule (coding)
           consumed_chars += nchars;
           char_offset++;
         }
+      else
+        goto invalid_code;
       continue;
 
     invalid_code: