(str_cmpchar_id): Check the byte sequence for

composition more rigidly.
(Fcompose_string): Allow DEL to be composed.  Signal error if STR
contains an invalid multibyte sequence.

diff --git a/src/charset.c b/src/charset.c
index 41b90189f1dca2ac48bbb6307461eb1f54842a4c..a96d39b4a563a421101958623e87731e4a12f98c 100644 (file)
--- a/src/charset.c
+++ b/src/charset.c
@@ -1417,7 +1417,12 @@ str_cmpchar_id (str, len)
     p = str + 1;
     while (p < endp)
       {
-       if (embedded_rule) p++;
+       if (embedded_rule)
+         {
+           p++;
+           if (p >= endp)
+             return -1;
+         }
        /* No need of checking if *P is 0xA0 because
           BYTES_BY_CHAR_HEAD (0x80) surely returns 2.  */
        p += BYTES_BY_CHAR_HEAD (*p - 0x20);
@@ -1719,7 +1724,7 @@ DEFUN ("compose-string", Fcompose_string, Scompose_string,
   i = 1;
   while (p < pend)
     {
-      if (*p < 0x20 || *p == 127) /* control code */
+      if (*p < 0x20) /* control code */
        error ("Invalid component character: %d", *p);
       else if (*p < 0x80)      /* ASCII */
        {
@@ -1740,6 +1745,8 @@ DEFUN ("compose-string", Fcompose_string, Scompose_string,
            error ("Can't compose a rule-based composition character");
          ptemp = p;
          while (! CHAR_HEAD_P (*p)) p++;
+         if (str_cmpchar_id (ptemp - 1, p - ptemp + 1) < 0)
+           error ("Can't compose an invalid composition character");
          if (i + (p - ptemp) >= MAX_LENGTH_OF_MULTI_BYTE_FORM)
            error ("Too long string to be composed: %s", XSTRING (str)->data);
          bcopy (ptemp, buf + i, p - ptemp);
@@ -1749,7 +1756,10 @@ DEFUN ("compose-string", Fcompose_string, Scompose_string,
        {
          /* Add 0x20 to the base leading-code, keep the remaining
              bytes unchanged.  */
-         len = BYTES_BY_CHAR_HEAD (*p);
+         int c = STRING_CHAR_AND_CHAR_LENGTH (p, pend - p, len);
+
+         if (len <= 1 || ! CHAR_VALID_P (c, 0))
+           error ("Can't compose an invalid character");
          if (i + len >= MAX_LENGTH_OF_MULTI_BYTE_FORM)
            error ("Too long string to be composed: %s", XSTRING (str)->data);
          bcopy (p, buf + i, len);