X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;ds=sidebyside;f=src%2Flanguage%2Flexer%2Fsegment.c;h=9c2c9b11e8eba18e34b13f40124e3eb3439a97ae;hb=76e0b3df102f54672f8d4dfcc19c144e52a8ff4e;hp=8d17ce38fe56b4de73d05b764c652a9d9a040594;hpb=012b9e4ecf47d844aea352b2c0b7dda80a7194bd;p=pspp

diff --git a/src/language/lexer/segment.c b/src/language/lexer/segment.c
index 8d17ce38fe..9c2c9b11e8 100644
--- a/src/language/lexer/segment.c
+++ b/src/language/lexer/segment.c
@@ -38,7 +38,9 @@ enum segmenter_state
     S_DOCUMENT_1,
     S_DOCUMENT_2,
     S_DOCUMENT_3,
-    S_FILE_LABEL,
+    S_FILE_LABEL_1,
+    S_FILE_LABEL_2,
+    S_FILE_LABEL_3,
     S_DO_REPEAT_1,
     S_DO_REPEAT_2,
     S_DO_REPEAT_3,
@@ -50,8 +52,6 @@ enum segmenter_state
     S_BEGIN_DATA_2,
     S_BEGIN_DATA_3,
     S_BEGIN_DATA_4,
-    S_TITLE_1,
-    S_TITLE_2
   };
 
 #define SS_START_OF_LINE (1u << 0)
@@ -227,7 +227,7 @@ is_all_spaces (const char *input_, size_t n)
   for (int ofs = 0; ofs < n; ofs += mblen)
     {
       ucs4_t uc;
-      mblen = u8_mbtouc (&uc, input, n);
+      mblen = u8_mbtouc (&uc, input + ofs, n - ofs);
       if (!lex_uc_is_space (uc))
         return false;
     }
@@ -759,18 +759,6 @@ segmenter_parse_id__ (struct segmenter *s, const char *input, size_t n,
           *type = SEG_START_DOCUMENT;
           return 0;
         }
-      else if (lex_id_match (ss_cstr ("TITLE"), word)
-               || lex_id_match (ss_cstr ("SUBTITLE"), word))
-        {
-          int result = segmenter_unquoted (input, n, eof, ofs);
-          if (result < 0)
-            return -1;
-          else if (result)
-            {
-              s->state = S_TITLE_1;
-              return ofs;
-            }
-        }
       else if (lex_id_match_n (ss_cstr ("DEFINE"), word, 6))
         {
           s->state = S_DEFINE_1;
@@ -784,7 +772,7 @@ segmenter_parse_id__ (struct segmenter *s, const char *input, size_t n,
             return -1;
           else if (lex_id_match (ss_cstr ("LABEL"), ss_cstr (id)))
             {
-              s->state = S_FILE_LABEL;
+              s->state = S_FILE_LABEL_1;
               s->substate = 0;
               return ofs;
             }
@@ -1257,9 +1245,9 @@ segmenter_parse_start_of_line__ (struct segmenter *s,
 }
 
 static int
-segmenter_parse_file_label__ (struct segmenter *s,
-                              const char *input, size_t n, bool eof,
-                              enum segment_type *type)
+segmenter_parse_file_label_1__ (struct segmenter *s,
+                                const char *input, size_t n, bool eof,
+                                enum segment_type *type)
 {
   struct segmenter sub;
   int ofs;
@@ -1282,7 +1270,7 @@ segmenter_parse_file_label__ (struct segmenter *s,
       else
         {
           if (result)
-            s->state = S_TITLE_1;
+            s->state = S_FILE_LABEL_2;
           else
             *s = sub;
           return ofs;
@@ -1295,6 +1283,70 @@ segmenter_parse_file_label__ (struct segmenter *s,
     }
 }
 
+static int
+segmenter_parse_file_label_2__ (struct segmenter *s,
+                                const char *input, size_t n, bool eof,
+                                enum segment_type *type)
+{
+  int ofs;
+
+  ofs = skip_spaces (input, n, eof, 0);
+  if (ofs < 0)
+    return -1;
+  s->state = S_FILE_LABEL_3;
+  *type = SEG_SPACES;
+  return ofs;
+}
+
+static int
+segmenter_parse_file_label_3__ (struct segmenter *s,
+                                const char *input, size_t n, bool eof,
+                                enum segment_type *type)
+{
+  int endcmd;
+  int ofs;
+
+  endcmd = -1;
+  ofs = 0;
+  while (ofs < n)
+    {
+      ucs4_t uc;
+      int mblen;
+
+      mblen = segmenter_u8_to_uc__ (&uc, input, n, eof, ofs);
+      if (mblen < 0)
+        return -1;
+
+      switch (uc)
+        {
+        case '\n':
+          goto end_of_line;
+
+        case '.':
+          endcmd = ofs;
+          break;
+
+        default:
+          if (!lex_uc_is_space (uc))
+            endcmd = -1;
+          break;
+        }
+
+      ofs += mblen;
+    }
+
+  if (eof)
+    {
+    end_of_line:
+      s->state = S_GENERAL;
+      s->substate = 0;
+      *type = SEG_UNQUOTED_STRING;
+      return endcmd >= 0 ? endcmd : ofs;
+    }
+
+  return -1;
+}
+
 static int
 segmenter_subparse (struct segmenter *s,
                     const char *input, size_t n, bool eof,
@@ -1512,7 +1564,10 @@ segmenter_parse_define_2__ (struct segmenter *s,
     {
       s->nest--;
       if (!s->nest)
-        s->state = S_DEFINE_3;
+        {
+          s->state = S_DEFINE_3;
+          s->substate = 0;
+        }
       return ofs;
     }
 
@@ -1524,11 +1579,33 @@ find_enddefine (struct substring input)
 {
   size_t n = input.length;
   const struct substring enddefine = ss_cstr ("!ENDDEFINE");
-  for (size_t i = 0; i + enddefine.length <= n; i++)
-    if (input.string[i] == '!'
-        && ss_equals_case (ss_substr (input, i, enddefine.length), enddefine))
-      return i;
-  return SIZE_MAX;
+  for (int ofs = 0;;)
+    {
+      /* Skip !ENDDEFINE in comment. */
+      ofs = skip_spaces_and_comments (input.string, n, true, ofs);
+      if (ofs + enddefine.length > n)
+        return SIZE_MAX;
+
+      char c = input.string[ofs];
+      if (c == '!'
+               && ss_equals_case (ss_substr (input, ofs, enddefine.length),
+                                  enddefine))
+        return ofs;
+      else if (c == '\'' || c == '"')
+        {
+          /* Skip quoted !ENDDEFINE. */
+          ofs++;
+          for (;;)
+            {
+              if (ofs >= n)
+                return SIZE_MAX;
+              else if (input.string[ofs++] == c)
+                break;
+            }
+        }
+      else
+        ofs++;
+    }
 }
 
 /* We are in the body of a macro definition, looking for additional lines of
@@ -1554,9 +1631,15 @@ segmenter_parse_define_3__ (struct segmenter *s,
 
          The line might be blank, whether completely empty or just spaces and
          comments.  That's OK: we need to report blank lines because they can
-         have significance. */
-      *type = SEG_MACRO_BODY;
+         have significance.
+
+         However, if the first line of the macro body (the same line as the
+         closing parenthesis in the argument definition) is blank, we just
+         report it as spaces because it's not significant. */
+      *type = (s->substate == 0 && is_all_spaces (input, ofs)
+               ? SEG_SPACES : SEG_MACRO_BODY);
       s->state = S_DEFINE_4;
+      s->substate = 1;
       return ofs;
     }
   else
@@ -1708,70 +1791,6 @@ segmenter_parse_begin_data_4__ (struct segmenter *s,
   return ofs;
 }
 
-static int
-segmenter_parse_title_1__ (struct segmenter *s,
-                           const char *input, size_t n, bool eof,
-                           enum segment_type *type)
-{
-  int ofs;
-
-  ofs = skip_spaces (input, n, eof, 0);
-  if (ofs < 0)
-    return -1;
-  s->state = S_TITLE_2;
-  *type = SEG_SPACES;
-  return ofs;
-}
-
-static int
-segmenter_parse_title_2__ (struct segmenter *s,
-                           const char *input, size_t n, bool eof,
-                           enum segment_type *type)
-{
-  int endcmd;
-  int ofs;
-
-  endcmd = -1;
-  ofs = 0;
-  while (ofs < n)
-    {
-      ucs4_t uc;
-      int mblen;
-
-      mblen = segmenter_u8_to_uc__ (&uc, input, n, eof, ofs);
-      if (mblen < 0)
-        return -1;
-
-      switch (uc)
-        {
-        case '\n':
-          goto end_of_line;
-
-        case '.':
-          endcmd = ofs;
-          break;
-
-        default:
-          if (!lex_uc_is_space (uc))
-            endcmd = -1;
-          break;
-        }
-
-      ofs += mblen;
-    }
-
-  if (eof)
-    {
-    end_of_line:
-      s->state = S_GENERAL;
-      s->substate = 0;
-      *type = SEG_UNQUOTED_STRING;
-      return endcmd >= 0 ? endcmd : ofs;
-    }
-
-  return -1;
-}
-
 /* Returns the name of segment TYPE as a string.  The caller must not modify
    or free the returned string.
 
@@ -1789,17 +1808,28 @@ segment_type_to_string (enum segment_type type)
     }
 }
 
-/* Initializes S as a segmenter with the given syntax MODE.
+/* Returns a segmenter with the given syntax MODE.
+
+   If IS_SNIPPET is false, then the segmenter will parse as if it's being given
+   a whole file.  This means, for example, that it will interpret - or + at the
+   beginning of the syntax as a separator between commands (since - or + at the
+   beginning of a line has this meaning).
+
+   If IS_SNIPPET is true, then the segmenter will parse as if it's being given
+   an isolated piece of syntax.  This means that, for example, that it will
+   interpret - or + at the beginning of the syntax as an operator token or (if
+   followed by a digit) as part of a number.
 
    A segmenter does not contain any external references, so nothing needs to be
    done to destroy one.  For the same reason, segmenters may be copied with
    plain struct assignment (or memcpy). */
-void
-segmenter_init (struct segmenter *s, enum segmenter_mode mode)
+struct segmenter
+segmenter_init (enum segmenter_mode mode, bool is_snippet)
 {
-  s->state = S_SHBANG;
-  s->substate = 0;
-  s->mode = mode;
+  return (struct segmenter) {
+    .state = is_snippet ? S_GENERAL : S_SHBANG,
+    .mode = mode,
+  };
 }
 
 /* Returns the mode passed to segmenter_init() for S. */
@@ -1872,8 +1902,12 @@ segmenter_push (struct segmenter *s, const char *input, size_t n, bool eof,
     case S_DOCUMENT_3:
       return segmenter_parse_document_3__ (s, type);
 
-    case S_FILE_LABEL:
-      return segmenter_parse_file_label__ (s, input, n, eof, type);
+    case S_FILE_LABEL_1:
+      return segmenter_parse_file_label_1__ (s, input, n, eof, type);
+    case S_FILE_LABEL_2:
+      return segmenter_parse_file_label_2__ (s, input, n, eof, type);
+    case S_FILE_LABEL_3:
+      return segmenter_parse_file_label_3__ (s, input, n, eof, type);
 
     case S_DO_REPEAT_1:
       return segmenter_parse_do_repeat_1__ (s, input, n, eof, type);
@@ -1899,11 +1933,6 @@ segmenter_push (struct segmenter *s, const char *input, size_t n, bool eof,
       return segmenter_parse_begin_data_3__ (s, input, n, eof, type);
     case S_BEGIN_DATA_4:
       return segmenter_parse_begin_data_4__ (s, input, n, eof, type);
-
-    case S_TITLE_1:
-      return segmenter_parse_title_1__ (s, input, n, eof, type);
-    case S_TITLE_2:
-      return segmenter_parse_title_2__ (s, input, n, eof, type);
     }
 
   NOT_REACHED ();
@@ -1934,8 +1963,11 @@ segmenter_get_prompt (const struct segmenter *s)
     case S_DOCUMENT_3:
       return PROMPT_FIRST;
 
-    case S_FILE_LABEL:
+    case S_FILE_LABEL_1:
       return PROMPT_LATER;
+    case S_FILE_LABEL_2:
+    case S_FILE_LABEL_3:
+      return PROMPT_FIRST;
 
     case S_DO_REPEAT_1:
     case S_DO_REPEAT_2:
@@ -1958,9 +1990,6 @@ segmenter_get_prompt (const struct segmenter *s)
     case S_BEGIN_DATA_4:
       return PROMPT_DATA;
 
-    case S_TITLE_1:
-    case S_TITLE_2:
-      return PROMPT_FIRST;
     }
 
   NOT_REACHED ();