(detect_coding_iso2022): Don't check the byte length of

succeeding codes (0xa0..0xFF) if the codes follows single shit
code.

diff --git a/src/coding.c b/src/coding.c
index 6b105b9..9e6333f 100644 (file)
--- a/src/coding.c
+++ b/src/coding.c
@@ -683,7 +683,7 @@ detect_coding_iso2022 (src, src_end)
 {
   int mask = CODING_CATEGORY_MASK_ISO;
   int mask_found = 0;
-  int reg[4], shift_out = 0;
+  int reg[4], shift_out = 0, single_shifting = 0;
   int c, c1, i, charset;
 
   reg[0] = CHARSET_ASCII, reg[1] = reg[2] = reg[3] = -1;
@@ -693,6 +693,7 @@ detect_coding_iso2022 (src, src_end)
       switch (c)
        {
        case ISO_CODE_ESC:
+         single_shifting = 0;
          if (src >= src_end)
            break;
          c = *src++;
@@ -781,6 +782,7 @@ detect_coding_iso2022 (src, src_end)
          break;
 
        case ISO_CODE_SO:
+         single_shifting = 0;
          if (shift_out == 0
              && (reg[1] >= 0
                  || SHIFT_OUT_OK (CODING_CATEGORY_IDX_ISO_7_ELSE)
@@ -793,6 +795,7 @@ detect_coding_iso2022 (src, src_end)
          break;
          
        case ISO_CODE_SI:
+         single_shifting = 0;
          if (shift_out == 1)
            {
              /* Locking shift in.  */
@@ -802,6 +805,7 @@ detect_coding_iso2022 (src, src_end)
          break;
 
        case ISO_CODE_CSI:
+         single_shifting = 0;
        case ISO_CODE_SS2:
        case ISO_CODE_SS3:
          {
@@ -815,6 +819,7 @@ detect_coding_iso2022 (src, src_end)
                if (coding_system_table[CODING_CATEGORY_IDX_ISO_8_2]->flags
                    & CODING_FLAG_ISO_SINGLE_SHIFT)
                  newmask |= CODING_CATEGORY_MASK_ISO_8_2;
+               single_shifting = 1;
              }
            if (VECTORP (Vlatin_extra_code_table)
                && !NILP (XVECTOR (Vlatin_extra_code_table)->contents[c]))
@@ -833,9 +838,13 @@ detect_coding_iso2022 (src, src_end)
 
        default:
          if (c < 0x80)
-           break;
+           {
+             single_shifting = 0;
+             break;
+           }
          else if (c < 0xA0)
            {
+             single_shifting = 0;
              if (VECTORP (Vlatin_extra_code_table)
                  && !NILP (XVECTOR (Vlatin_extra_code_table)->contents[c]))
                {
@@ -860,12 +869,19 @@ detect_coding_iso2022 (src, src_end)
              mask &= ~(CODING_CATEGORY_MASK_ISO_7BIT
                        | CODING_CATEGORY_MASK_ISO_7_ELSE);
              mask_found |= CODING_CATEGORY_MASK_ISO_8_1;
-             while (src < src_end && *src >= 0xA0)
-               src++;
-             if ((src - src_begin - 1) & 1 && src < src_end)
-               mask &= ~CODING_CATEGORY_MASK_ISO_8_2;
-             else
-               mask_found |= CODING_CATEGORY_MASK_ISO_8_2;
+             /* Check the length of succeeding codes of the range
+                 0xA0..0FF.  If the byte length is odd, we exclude
+                 CODING_CATEGORY_MASK_ISO_8_2.  We can check this only
+                 when we are not single shifting.  */
+             if (!single_shifting)
+               {
+                 while (src < src_end && *src >= 0xA0)
+                   src++;
+                 if ((src - src_begin - 1) & 1 && src < src_end)
+                   mask &= ~CODING_CATEGORY_MASK_ISO_8_2;
+                 else
+                   mask_found |= CODING_CATEGORY_MASK_ISO_8_2;
+               }
            }
          break;
        }