1 files changed, 113 insertions, 84 deletions

diff --git a/src/coding.c b/src/coding.c
index d618f4d4497..0761425dcd8 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -1418,26 +1418,6 @@ detect_coding_utf_16 (coding, detect_info)
     }
   else if (c1 >= 0 && c2 >= 0)
     {
-      unsigned char b1[256], b2[256];
-      int b1_variants = 1, b2_variants = 1;
-      int n;
-
-      bzero (b1, 256), bzero (b2, 256);
-      b1[c1]++, b2[c2]++;
-      for (n = 0; n < 256 && src < src_end; n++)
-        {
-          src_base = src;
-          ONE_MORE_BYTE (c1);
-          ONE_MORE_BYTE (c2);
-          if (c1 < 0 || c2 < 0)
-            break;
-          if (! b1[c1++]) b1_variants++;
-          if (! b2[c2++]) b2_variants++;
-        }
-      if (b1_variants < b2_variants)
-        detect_info->found |= CATEGORY_MASK_UTF_16_BE_NOSIG;
-      else
-        detect_info->found |= CATEGORY_MASK_UTF_16_LE_NOSIG;      
       detect_info->rejected
         |= (CATEGORY_MASK_UTF_16_BE | CATEGORY_MASK_UTF_16_LE);
     }
@@ -5421,53 +5401,78 @@ detect_coding (coding)
   if (EQ (CODING_ATTR_TYPE (CODING_ID_ATTRS (coding->id)), Qundecided))
     {
       int c, i;
+      struct coding_detection_info detect_info;
 
+      detect_info.checked = detect_info.found = detect_info.rejected = 0;
       for (i = 0, src = coding->source; src < src_end; i++, src++)
         {
           c = *src;
-          if (c & 0x80 || (c < 0x20 && (c == ISO_CODE_ESC
-                                        || c == ISO_CODE_SI
-                                        || c == ISO_CODE_SO)))
+          if (c & 0x80)
             break;
+          if (c < 0x20
+              && (c == ISO_CODE_ESC || c == ISO_CODE_SI || c == ISO_CODE_SO)
+              && ! inhibit_iso_escape_detection
+              && ! detect_info.checked)
+            {
+              coding->head_ascii = src - (coding->source + coding->consumed);
+              if (detect_coding_iso_2022 (coding, &detect_info))
+                {
+                  /* We have scanned the whole data.  */
+                  if (! (detect_info.rejected & CATEGORY_MASK_ISO_7_ELSE))
+                    /* We didn't find an 8-bit code.  */
+                    src = src_end;
+                  break;
+                }
+            }
         }
       coding->head_ascii = src - (coding->source + coding->consumed);
 
-      if (coding->head_ascii < coding->src_bytes)
+      if (coding->head_ascii == coding->src_bytes
+          || detect_info.found)
         {
-          struct coding_detection_info detect_info;
           enum coding_category category;
           struct coding_system *this;
 
-          detect_info.checked = detect_info.found = detect_info.rejected = 0;
-          for (i = 0; i < coding_category_raw_text; i++)
-            {
-              category = coding_priorities[i];
-              this = coding_categories + category;
-              if (this->id < 0)
-                {
-                  /* No coding system of this category is defined.  */
-                  detect_info.rejected |= (1 << category);
-                }
-              else if (category >= coding_category_raw_text)
-                continue;
-              else if (detect_info.checked & (1 << category))
-                {
-                  if (detect_info.found & (1 << category))
-                    break;
-                }
-              else if ((*(this->detector)) (coding, &detect_info)
-                       && detect_info.found & (1 << category))
-                {
-                  if (category == coding_category_utf_16_auto)
-                    {
-                      if (detect_info.found & CATEGORY_MASK_UTF_16_LE)
-                        category = coding_category_utf_16_le;
-                      else
-                        category = coding_category_utf_16_be;
-                    }
+          if (coding->head_ascii == coding->src_bytes)
+            /* As all bytes are 7-bit, we can ignore non-ISO-2022 codings.  */
+            for (i = 0; i < coding_category_raw_text; i++)
+              {
+                category = coding_priorities[i];
+                this = coding_categories + category;
+                if (detect_info.found & (1 << category))
                   break;
-                }
-            }
+              }
+          else
+            for (i = 0; i < coding_category_raw_text; i++)
+              {
+                category = coding_priorities[i];
+                this = coding_categories + category;
+                if (this->id < 0)
+                  {
+                    /* No coding system of this category is defined.  */
+                    detect_info.rejected |= (1 << category);
+                  }
+                else if (category >= coding_category_raw_text)
+                  continue;
+                else if (detect_info.checked & (1 << category))
+                  {
+                    if (detect_info.found & (1 << category))
+                      break;
+                  }
+                else if ((*(this->detector)) (coding, &detect_info)
+                         && detect_info.found & (1 << category))
+                  {
+                    if (category == coding_category_utf_16_auto)
+                      {
+                        if (detect_info.found & CATEGORY_MASK_UTF_16_LE)
+                          category = coding_category_utf_16_le;
+                        else
+                          category = coding_category_utf_16_be;
+                      }
+                    break;
+                  }
+              }
+          
           if (i < coding_category_raw_text)
             setup_coding_system (CODING_ID_NAME (this->id), coding);
           else if (detect_info.rejected == CATEGORY_MASK_ANY)
@@ -7120,49 +7125,73 @@ detect_coding_system (src, src_chars, src_bytes, highest, multibytep,
       for (i = 0; src < src_end; i++, src++)
         {
           c = *src;
-          if (c & 0x80 || (c < 0x20 && (c == ISO_CODE_ESC
-                                        || c == ISO_CODE_SI
-                                        || c == ISO_CODE_SO)))
+          if (c & 0x80)
             break;
+          if (c < 0x20
+              && (c == ISO_CODE_ESC || c == ISO_CODE_SI || c == ISO_CODE_SO)
+              && inhibit_iso_escape_detection)
+            {
+              coding.head_ascii = src - coding.source;
+              if (detect_coding_iso_2022 (&coding, &detect_info))
+                {
+                  /* We have scanned the whole data.  */
+                  if (! (detect_info.rejected & CATEGORY_MASK_ISO_7_ELSE))
+                    /* We didn't find an 8-bit code.  */
+                    src = src_end;
+                  break;
+                }
+            }
         }
       coding.head_ascii = src - coding.source;
 
-      if (src < src_end)
-        for (i = 0; i < coding_category_raw_text; i++)
-          {
-            category = coding_priorities[i];
-            this = coding_categories + category;
-
-            if (this->id < 0)
-              {
-                /* No coding system of this category is defined.  */
-                detect_info.rejected |= (1 << category);
-              }
-            else if (category >= coding_category_raw_text)
-              continue;
-            else if (detect_info.checked & (1 << category))
+      if (src < src_end
+          || detect_info.found)
+        {
+          if (src == src_end)
+            /* As all bytes are 7-bit, we can ignore non-ISO-2022 codings.  */
+            for (i = 0; i < coding_category_raw_text; i++)
               {
-                if (highest
-                    && (detect_info.found & (1 << category)))
+                category = coding_priorities[i];
+                if (detect_info.found & (1 << category))
                   break;
               }
-            else
+          else
+            for (i = 0; i < coding_category_raw_text; i++)
               {
-                if ((*(this->detector)) (&coding, &detect_info)
-                    && highest
-                    && (detect_info.found & (1 << category)))
+                category = coding_priorities[i];
+                this = coding_categories + category;
+
+                if (this->id < 0)
                   {
-                    if (category == coding_category_utf_16_auto)
+                    /* No coding system of this category is defined.  */
+                    detect_info.rejected |= (1 << category);
+                  }
+                else if (category >= coding_category_raw_text)
+                  continue;
+                else if (detect_info.checked & (1 << category))
+                  {
+                    if (highest
+                        && (detect_info.found & (1 << category)))
+                      break;
+                  }
+                else
+                  {
+                    if ((*(this->detector)) (&coding, &detect_info)
+                        && highest
+                        && (detect_info.found & (1 << category)))
                       {
-                        if (detect_info.found & CATEGORY_MASK_UTF_16_LE)
-                          category = coding_category_utf_16_le;
-                        else
-                          category = coding_category_utf_16_be;
+                        if (category == coding_category_utf_16_auto)
+                          {
+                            if (detect_info.found & CATEGORY_MASK_UTF_16_LE)
+                              category = coding_category_utf_16_le;
+                            else
+                              category = coding_category_utf_16_be;
+                          }
+                        break;
                       }
-                    break;
                   }
               }
-          }
+        }
 
       if (detect_info.rejected == CATEGORY_MASK_ANY)
         {