Fix the setting of buffer-file-coding-system on, for instance, C-x RET c unix RET _FILE_OF_DOS_EOL_TYPE_ RET.

1 files changed, 154 insertions, 67 deletions

diff --git a/src/coding.c b/src/coding.c
index f6664e179b7..42fd81b6322 100644
--- a/src/coding.c
+++ b/src/coding.c
@@ -1125,6 +1125,14 @@ alloc_destination (struct coding_system *coding, ptrdiff_t nbytes,
     *buf++ = id;                                                        \
   } while (0)
 
+
+/* Bitmasks for coding->eol_seen.  */
+
+#define EOL_SEEN_NONE   0
+#define EOL_SEEN_LF     1
+#define EOL_SEEN_CR     2
+#define EOL_SEEN_CRLF   4
+
 
 /*** 2. Emacs' internal format (emacs-utf-8) ***/
 
@@ -1147,6 +1155,9 @@ alloc_destination (struct coding_system *coding, ptrdiff_t nbytes,
 #define UTF_8_BOM_2 0xBB
 #define UTF_8_BOM_3 0xBF
 
+/* Unlike the other detect_coding_XXX, this function counts number of
+   characters and check EOL format.  */
+
 static bool
 detect_coding_utf_8 (struct coding_system *coding,
                      struct coding_detection_info *detect_info)
@@ -1156,11 +1167,23 @@ detect_coding_utf_8 (struct coding_system *coding,
   bool multibytep = coding->src_multibyte;
   ptrdiff_t consumed_chars = 0;
   bool bom_found = 0;
-  bool found = 0;
+  int nchars = coding->head_ascii;
+  int eol_seen = coding->eol_seen;
 
   detect_info->checked |= CATEGORY_MASK_UTF_8;
   /* A coding system of this category is always ASCII compatible.  */
-  src += coding->head_ascii;
+  src += nchars;
+
+  if (src == coding->source     /* BOM should be at the head.  */
+      && src + 3 < src_end      /* BOM is 3-byte long.  */
+      && src[0] == UTF_8_BOM_1
+      && src[1] == UTF_8_BOM_2
+      && src[2] == UTF_8_BOM_3)
+    {
+      bom_found = 1;
+      src += 3;
+      nchars++;
+    }
 
   while (1)
     {
@@ -1169,13 +1192,29 @@ detect_coding_utf_8 (struct coding_system *coding,
       src_base = src;
       ONE_MORE_BYTE (c);
       if (c < 0 || UTF_8_1_OCTET_P (c))
-        continue;
+        {
+          nchars++;
+          if (c == '\r')
+            {
+              if (src < src_end && *src == '\n')
+                {
+                  eol_seen |= EOL_SEEN_CRLF;
+                  src++;
+                  nchars++;
+                }
+              else
+                eol_seen |= EOL_SEEN_CR;
+            }
+          else if (c == '\n')
+            eol_seen |= EOL_SEEN_LF;
+          continue;
+        }
       ONE_MORE_BYTE (c1);
       if (c1 < 0 || ! UTF_8_EXTRA_OCTET_P (c1))
         break;
       if (UTF_8_2_OCTET_LEADING_P (c))
         {
-          found = 1;
+          nchars++;
           continue;
         }
       ONE_MORE_BYTE (c2);
@@ -1183,10 +1222,7 @@ detect_coding_utf_8 (struct coding_system *coding,
         break;
       if (UTF_8_3_OCTET_LEADING_P (c))
         {
-          found = 1;
-          if (src_base == coding->source
-              && c == UTF_8_BOM_1 && c1 == UTF_8_BOM_2 && c2 == UTF_8_BOM_3)
-            bom_found = 1;
+          nchars++;
           continue;
         }
       ONE_MORE_BYTE (c3);
@@ -1194,7 +1230,7 @@ detect_coding_utf_8 (struct coding_system *coding,
         break;
       if (UTF_8_4_OCTET_LEADING_P (c))
         {
-          found = 1;
+          nchars++;
           continue;
         }
       ONE_MORE_BYTE (c4);
@@ -1202,7 +1238,7 @@ detect_coding_utf_8 (struct coding_system *coding,
         break;
       if (UTF_8_5_OCTET_LEADING_P (c))
         {
-          found = 1;
+          nchars++;
           continue;
         }
       break;
@@ -1219,14 +1255,17 @@ detect_coding_utf_8 (struct coding_system *coding,
   if (bom_found)
     {
       /* The first character 0xFFFE doesn't necessarily mean a BOM.  */
-      detect_info->found |= CATEGORY_MASK_UTF_8_SIG | CATEGORY_MASK_UTF_8_NOSIG;
+      detect_info->found |= CATEGORY_MASK_UTF_8_AUTO | CATEGORY_MASK_UTF_8_SIG | CATEGORY_MASK_UTF_8_NOSIG;
     }
   else
     {
       detect_info->rejected |= CATEGORY_MASK_UTF_8_SIG;
-      if (found)
-        detect_info->found |= CATEGORY_MASK_UTF_8_NOSIG;
+      if (nchars < src_end - coding->source)
+        /* The found characters are less than source bytes, which
+           means that we found a valid non-ASCII characters.  */
+        detect_info->found |= CATEGORY_MASK_UTF_8_AUTO | CATEGORY_MASK_UTF_8_NOSIG;
     }
+  coding->detected_utf8_chars = nchars;
   return 1;
 }
 
@@ -5622,7 +5661,6 @@ setup_coding_system (Lisp_Object coding_system, struct coding_system *coding)
   eol_type = inhibit_eol_conversion ? Qunix : CODING_ID_EOL_TYPE (coding->id);
 
   coding->mode = 0;
-  coding->head_ascii = -1;
   if (VECTORP (eol_type))
     coding->common_flags = (CODING_REQUIRE_DECODING_MASK
                             | CODING_REQUIRE_DETECTION_MASK);
@@ -6074,46 +6112,35 @@ complement_process_encoding_system (Lisp_Object coding_system)
 
 */
 
-#define EOL_SEEN_NONE   0
-#define EOL_SEEN_LF     1
-#define EOL_SEEN_CR     2
-#define EOL_SEEN_CRLF   4
-
-
 static Lisp_Object adjust_coding_eol_type (struct coding_system *coding,
                                            int eol_seen);
 
 
 /* Return the number of ASCII characters at the head of the source.
-   By side effects, set coding->head_ascii and coding->eol_seen.  The
-   value of coding->eol_seen is "logical or" of EOL_SEEN_LF,
-   EOL_SEEN_CR, and EOL_SEEN_CRLF, but the value is reliable only when
-   all the source bytes are ASCII.  */
+   By side effects, set coding->head_ascii and update
+   coding->eol_seen.  The value of coding->eol_seen is "logical or" of
+   EOL_SEEN_LF, EOL_SEEN_CR, and EOL_SEEN_CRLF, but the value is
+   reliable only when all the source bytes are ASCII.  */
 
 static int
 check_ascii (struct coding_system *coding)
 {
   const unsigned char *src, *end;
   Lisp_Object eol_type = CODING_ID_EOL_TYPE (coding->id);
-  int eol_seen;
+  int eol_seen = coding->eol_seen;
 
-  eol_seen = (VECTORP (eol_type) ? EOL_SEEN_NONE
-              : EQ (eol_type, Qunix) ? EOL_SEEN_LF
-              : EQ (eol_type, Qdos) ? EOL_SEEN_CRLF
-              : EOL_SEEN_CR);
   coding_set_source (coding);
   src = coding->source;
   end = src + coding->src_bytes;
 
   if (inhibit_eol_conversion
-      || eol_seen != EOL_SEEN_NONE)
+      || SYMBOLP (eol_type))
     {
       /* We don't have to check EOL format.  */
-      while (src < end && !( *src & 0x80)) src++;
-      if (inhibit_eol_conversion)
+      while (src < end && !( *src & 0x80))
         {
-          eol_seen = EOL_SEEN_LF;
-          adjust_coding_eol_type (coding, eol_seen);
+          if (*src++ == '\n')
+            eol_seen |= EOL_SEEN_LF;
         }
     }
   else
@@ -6171,7 +6198,7 @@ static int
 check_utf_8 (struct coding_system *coding)
 {
   const unsigned char *src, *end;
-  int eol_seen = coding->eol_seen;
+  int eol_seen;
   int nchars = coding->head_ascii;
 
   if (coding->head_ascii < 0)
@@ -6181,7 +6208,7 @@ check_utf_8 (struct coding_system *coding)
   src = coding->source + coding->head_ascii;
   /* We look ahead one byte for CR LF.  */
   end = coding->source + coding->src_bytes - 1;
-
+  eol_seen = coding->eol_seen;
   while (src < end)
     {
       int c = *src;
@@ -6402,6 +6429,8 @@ detect_coding (struct coding_system *coding)
 {
   const unsigned char *src, *src_end;
   unsigned int saved_mode = coding->mode;
+  Lisp_Object found = Qnil;
+  Lisp_Object eol_type = CODING_ID_EOL_TYPE (coding->id);
 
   coding->consumed = coding->consumed_char = 0;
   coding->produced = coding->produced_char = 0;
@@ -6409,6 +6438,7 @@ detect_coding (struct coding_system *coding)
 
   src_end = coding->source + coding->src_bytes;
 
+  coding->eol_seen = EOL_SEEN_NONE;
   /* If we have not yet decided the text encoding type, detect it
      now.  */
   if (EQ (CODING_ATTR_TYPE (CODING_ID_ATTRS (coding->id)), Qundecided))
@@ -6418,7 +6448,6 @@ detect_coding (struct coding_system *coding)
       bool null_byte_found = 0, eight_bit_found = 0;
 
       coding->head_ascii = 0;
-      coding->eol_seen = EOL_SEEN_NONE;
       detect_info.checked = detect_info.found = detect_info.rejected = 0;
       for (src = coding->source; src < src_end; src++)
         {
@@ -6529,32 +6558,58 @@ detect_coding (struct coding_system *coding)
                     }
                   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;
-                    }
+                    break;
                 }
             }
 
           if (i < coding_category_raw_text)
-            setup_coding_system (CODING_ID_NAME (this->id), coding);
+            {
+              if (category == coding_category_utf_8_auto)
+                {
+                  Lisp_Object coding_systems;
+
+                  coding_systems = AREF (CODING_ID_ATTRS (this->id),
+                                         coding_attr_utf_bom);
+                  if (CONSP (coding_systems))
+                    {
+                      if (detect_info.found & CATEGORY_MASK_UTF_8_SIG)
+                        found = XCAR (coding_systems);
+                      else
+                        found = XCDR (coding_systems);
+                    }
+                  else
+                    found = CODING_ID_NAME (this->id);
+                }
+              else if (category == coding_category_utf_16_auto)
+                {
+                  Lisp_Object coding_systems;
+
+                  coding_systems = AREF (CODING_ID_ATTRS (this->id),
+                                         coding_attr_utf_bom);
+                  if (CONSP (coding_systems))
+                    {
+                      if (detect_info.found & CATEGORY_MASK_UTF_16_LE)
+                        found = XCAR (coding_systems);
+                      else if (detect_info.found & CATEGORY_MASK_UTF_16_BE)
+                        found = XCDR (coding_systems);
+                    }
+                  else
+                    found = CODING_ID_NAME (this->id);
+                }
+              else
+                found = CODING_ID_NAME (this->id);
+            }
           else if (null_byte_found)
-            setup_coding_system (Qno_conversion, coding);
+            found = Qno_conversion;
           else if ((detect_info.rejected & CATEGORY_MASK_ANY)
                    == CATEGORY_MASK_ANY)
-            setup_coding_system (Qraw_text, coding);
+            found = Qraw_text;
           else if (detect_info.rejected)
             for (i = 0; i < coding_category_raw_text; i++)
               if (! (detect_info.rejected & (1 << coding_priorities[i])))
                 {
                   this = coding_categories + coding_priorities[i];
-                  setup_coding_system (CODING_ID_NAME (this->id), coding);
+                  found = CODING_ID_NAME (this->id);
                   break;
                 }
         }
@@ -6570,12 +6625,8 @@ detect_coding (struct coding_system *coding)
       detect_info.found = detect_info.rejected = 0;
       if (check_ascii (coding) == coding->src_bytes)
         {
-          int head_ascii = coding->head_ascii;
-
-          if (coding->eol_seen != EOL_SEEN_NONE)
-            adjust_coding_eol_type (coding, coding->eol_seen);
-          setup_coding_system (XCDR (coding_systems), coding);
-          coding->head_ascii = head_ascii;
+          if (CONSP (coding_systems))
+            found = XCDR (coding_systems);
         }
       else
         {
@@ -6583,9 +6634,9 @@ detect_coding (struct coding_system *coding)
               && detect_coding_utf_8 (coding, &detect_info))
             {
               if (detect_info.found & CATEGORY_MASK_UTF_8_SIG)
-                setup_coding_system (XCAR (coding_systems), coding);
+                found = XCAR (coding_systems);
               else
-                setup_coding_system (XCDR (coding_systems), coding);
+                found = XCDR (coding_systems);
             }
         }
     }
@@ -6599,16 +6650,28 @@ detect_coding (struct coding_system *coding)
         = AREF (CODING_ID_ATTRS (coding->id), coding_attr_utf_bom);
       detect_info.found = detect_info.rejected = 0;
       coding->head_ascii = 0;
-      coding->eol_seen = EOL_SEEN_NONE;
       if (CONSP (coding_systems)
           && detect_coding_utf_16 (coding, &detect_info))
         {
           if (detect_info.found & CATEGORY_MASK_UTF_16_LE)
-            setup_coding_system (XCAR (coding_systems), coding);
+            found = XCAR (coding_systems);
           else if (detect_info.found & CATEGORY_MASK_UTF_16_BE)
-            setup_coding_system (XCDR (coding_systems), coding);
+            found = XCDR (coding_systems);
         }
     }
+
+  if (! NILP (found))
+    {
+      int specified_eol = (VECTORP (eol_type) ? EOL_SEEN_NONE
+                           : EQ (eol_type, Qdos) ? EOL_SEEN_CRLF
+                           : EQ (eol_type, Qmac) ? EOL_SEEN_CR
+                           : EOL_SEEN_LF);
+
+      setup_coding_system (found, coding);
+      if (specified_eol != EOL_SEEN_NONE)
+        adjust_coding_eol_type (coding, specified_eol);
+    }
+
   coding->mode = saved_mode;
 }
 
@@ -7729,6 +7792,9 @@ decode_coding_gap (struct coding_system *coding,
   coding->dst_pos_byte = PT_BYTE;
   coding->dst_multibyte = ! NILP (BVAR (current_buffer, enable_multibyte_characters));
 
+  coding->head_ascii = -1;
+  coding->detected_utf8_chars = -1;
+  coding->eol_seen = EOL_SEEN_NONE;
   if (CODING_REQUIRE_DETECTION (coding))
     detect_coding (coding);
   attrs = CODING_ID_ATTRS (coding->id);
@@ -7743,17 +7809,38 @@ decode_coding_gap (struct coding_system *coding,
         chars = check_ascii (coding);
       if (chars != bytes)
         {
+          /* There exists a non-ASCII byte.  */
           if (EQ (CODING_ATTR_TYPE (attrs), Qutf_8))
-            chars = check_utf_8 (coding);
+            {
+              if (coding->detected_utf8_chars >= 0)
+                chars = coding->detected_utf8_chars;
+              else
+                chars = check_utf_8 (coding);
+              if (CODING_UTF_8_BOM (coding) != utf_without_bom
+                  && coding->head_ascii == 0
+                  && coding->source[0] == UTF_8_BOM_1
+                  && coding->source[1] == UTF_8_BOM_2
+                  && coding->source[2] == UTF_8_BOM_3)
+                {
+                  chars--;
+                  bytes -= 3;
+                  coding->src_bytes -= 3;
+                }
+            }
           else
             chars = -1;
         }
       if (chars >= 0)
         {
-          if (coding->eol_seen != EOL_SEEN_NONE)
-            adjust_coding_eol_type (coding, coding->eol_seen);
+          Lisp_Object eol_type;
 
-          if (coding->eol_seen == EOL_SEEN_CR)
+          eol_type = CODING_ID_EOL_TYPE (coding->id);
+          if (VECTORP (eol_type))
+            {
+              if (coding->eol_seen != EOL_SEEN_NONE)
+                eol_type = adjust_coding_eol_type (coding, coding->eol_seen);
+            }
+          if (EQ (eol_type, Qmac))
             {
               unsigned char *src_end = GAP_END_ADDR;
               unsigned char *src = src_end - coding->src_bytes;
@@ -7764,7 +7851,7 @@ decode_coding_gap (struct coding_system *coding,
                     src[-1] = '\n';
                 }
             }
-          else if (coding->eol_seen == EOL_SEEN_CRLF)
+          else if (EQ (eol_type, Qdos))
             {
               unsigned char *src = GAP_END_ADDR;
               unsigned char *src_beg = src - coding->src_bytes;