Mon Nov 8 19:56:20 MET 1993 Tom Hageman (tom@basil.icce.rug.nl)

	* etags.c: (C_entries): Keep track of ()-parenthesis level so that
	functions returning a pointer to a function, a la `signal', can be
	parsed.  This also required new state `fstartlist' to `FUNCST'.
	(SAVE_TOKEN, RESTORE_TOKEN, TOKEN_SAVED_P): 1-deep token save stack.
	(C_entries, CNL): use it to isolate preprocessor directive processing
	from the other state engines.
	(begtk): add '~', for C++ class destructors.

1 files changed, 139 insertions, 34 deletions

diff --git a/lib-src/etags.c b/lib-src/etags.c
index 305780082a8..bb1eb26f9d9 100644
--- a/lib-src/etags.c
+++ b/lib-src/etags.c
@@ -25,7 +25,7 @@ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */
  *      Gnu Emacs TAGS format and modifications by RMS?
  *      Sam Kendall added C++.
  *
- *      Francesco Potorti` (pot@cnuce.cnr.it) is the current maintainer. 9.7
+ *      Francesco Potorti` (pot@cnuce.cnr.it) is the current maintainer. 9.8
  */
 
 #ifdef HAVE_CONFIG_H
@@ -353,7 +353,7 @@ char *curfile,			/* current input file name		*/
  *white = " \f\t\n",            /* white chars                          */
  *endtk = " \t\n\"'#()[]{}=-+%*/&|^~!<>;,.:?",  /* token ending chars   */
                                 /* token starting chars                 */
- *begtk = "ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz$",
+ *begtk = "ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz$~",
                                   /* valid in-token chars               */
  *intk = "ABCDEFGHIJKLMNOPQRSTUVWXYZ_abcdefghijklmnopqrstuvwxyz$0123456789";
 
@@ -1331,6 +1331,7 @@ typedef enum
 {
   fnone,                        /* nothing seen */
   ftagseen,                     /* function-like tag seen */
+  fstartlist,                   /* just after open parenthesis */
   finlist,                      /* in parameter list */
   flistseen,                    /* after parameter list */
   fignore,                      /* before open brace */
@@ -1410,6 +1411,15 @@ logical yacc_rules;
 #define othlinepos (lbs[1-curndx].linepos)
 #define newlinepos (lbs[newndx].linepos)
 
+/* Save and restore token state.  This is used when preprocessor defines
+   are handled, to avoid disturbing active function/typedef/struct states.  */
+#define TOKEN_SAVED_P   (savetok.lineno > 0)
+#define SAVE_TOKEN      (savetok = tok, savetok.p = (char *) tokoff,    \
+                         savetok.len = toklen, strcpy(savenameb, nameb))
+#define RESTORE_TOKEN   (tok = savetok, tokoff = (int) tok.p,           \
+                         toklen = tok.len, strcpy(nameb, savenameb),    \
+                         savetok.lineno = 0)
+
 #define CNL_SAVE_DEFINEDEF                                              \
 do {                                                                    \
   SET_FILEPOS (curlinepos, inf, charno);                                \
@@ -1423,6 +1433,8 @@ do {									\
 #define CNL                                                             \
 do {                                                                    \
   CNL_SAVE_DEFINEDEF;                                                   \
+  if (TOKEN_SAVED_P)                                                    \
+    RESTORE_TOKEN;                                                      \
   definedef = dnone;                                                    \
 } while (FALSE)
 
@@ -1443,9 +1455,14 @@ C_entries (c_ext)
   register int tokoff;          /* offset in line of start of latest token */
   register int toklen;          /* length of latest token */
   int cblev;                    /* current curly brace level */
+  int parlev;                   /* current parenthesis level */
   logical incomm, inquote, inchar, quotednl, midtoken;
   logical cplpl;
+  TOKEN savetok;                /* saved token during preprocessor handling */
+  logical saveisfunc;
+  char savenameb[BUFSIZ];       /* ouch! */
 
+  savetok.lineno = 0;
   curndx = newndx = 0;
   lineno = 0;
   charno = 0;
@@ -1456,6 +1473,7 @@ C_entries (c_ext)
   next_token_is_func = yacc_rules = FALSE;
   midtoken = inquote = inchar = incomm = quotednl = FALSE;
   cblev = 0;
+  parlev = 0;
   cplpl = c_ext & C_PLPL;
 
   C_create_stabs ();
@@ -1522,9 +1540,13 @@ C_entries (c_ext)
           {
           case '"':
             inquote = TRUE;
+            if (funcdef != finlist && funcdef != fignore)
+              funcdef = fnone;
             continue;
           case '\'':
             inchar = TRUE;
+            if (funcdef != finlist && funcdef != fignore)
+              funcdef = fnone;
             continue;
           case '/':
             if (*lp == '*')
@@ -1538,7 +1560,8 @@ C_entries (c_ext)
                 c = 0;
                 break;
               }
-            continue;
+            else
+              break;
           case '%':
             if ((c_ext & YACC) && *lp == '%')
               {
@@ -1552,6 +1575,8 @@ C_entries (c_ext)
                 yacc_rules = !yacc_rules;
                 continue;
               }
+            else
+              break;
           case '#':
             if (lp == newlb.buffer + 1 && definedef == dnone)
               definedef = dsharpseen;
@@ -1563,13 +1588,14 @@ C_entries (c_ext)
       if (((cblev == 0 && structdef != scolonseen)
            || (cblev == 1 && cplpl && structdef == sinbody))
           && definedef != dignorerest
-          && funcdef != finlist)
+          && (funcdef != finlist
+              || (definedef != dnone && definedef != dignorerest)))
         {
           if (midtoken)
             {
               if (endtoken (c))
                 {
-                  if (cplpl && c == ':' && *lp == ':' && intoken (*(lp + 1)))
+                  if (cplpl && c == ':' && *lp == ':' && begtoken(*(lp + 1)))
                     {
                       /*
                        * This handles :: in the middle, but not at beginning
@@ -1610,9 +1636,10 @@ C_entries (c_ext)
                               || typdef == tend)
                             tok.named = TRUE;
 
-                          if (funcdef == ftagseen
-                              || structdef == stagseen
-                              || typdef == tend)
+                          if (definedef == dnone
+                              && (funcdef == ftagseen
+                                  || structdef == stagseen
+                                  || typdef == tend))
                             {
                               if (newndx == curndx)
                                 curndx = 1 - curndx; /* switch line buffers */
@@ -1631,18 +1658,40 @@ C_entries (c_ext)
             } /* if (midtoken) */
           else if (begtoken (c))
             {
-              switch (funcdef)
+              switch (definedef)
                 {
-                case flistseen:
-                  MAKE_TAG_FROM_OTH_LB (TRUE);
-                  funcdef = fignore;
-                  break;
-                case ftagseen:
-                  funcdef = fnone;
+                case dnone:
+                  switch (funcdef)
+                    {
+                    case fstartlist:
+                      funcdef = finlist;
+                      continue;
+                    case flistseen:
+                      MAKE_TAG_FROM_OTH_LB (TRUE);
+                      funcdef = fignore;
+                      break;
+                    case ftagseen:
+                      funcdef = fnone;
+                      break;
+                    }
+                  if (structdef == stagseen)
+                    structdef = snone;
                   break;
+                case dsharpseen:
+                  /* Take a quick peek ahead for define directive,
+                     so we can avoid saving the token when not absolutely
+                     necessary. [This is a speed hack.] */
+                  if (c == 'd' && strneq(lp, "efine", 5)
+                      && iswhite(*(lp + 5)))
+                    {
+                      SAVE_TOKEN;
+                      definedef = ddefineseen;
+                      lp += 6;
+                    }
+                  else
+                    definedef = dignorerest;
+                  continue;
                 }
-              if (structdef == stagseen)
-                structdef = snone;
               if (!yacc_rules || lp == newlb.buffer + 1)
                 {
                   tokoff = lp - 1 - newlb.buffer;
@@ -1655,19 +1704,32 @@ C_entries (c_ext)
 
 
       /* Detect end of line, colon, comma, semicolon and various braces
-         after having handled the last token on the line.*/
+         after having handled a token.*/
       switch (c)
         {
         case ':':
+          if (definedef != dnone)
+            break;
           if (structdef == stagseen)
             structdef = scolonseen;
-          else if (yacc_rules && funcdef == ftagseen)
-            {
-              MAKE_TAG_FROM_OTH_LB (FALSE);
-              funcdef = fignore;
-            }
+          else
+            switch (funcdef)
+              {
+              case ftagseen:
+                if (yacc_rules)
+                  {
+                    MAKE_TAG_FROM_OTH_LB (FALSE);
+                    funcdef = fignore;
+                  }
+                break;
+              case fstartlist:
+                funcdef = fnone;
+                break;
+              }
           break;
         case ';':
+          if (definedef != dnone)
+            break;
           if (cblev == 0 && typdef == tend)
             {
               typdef = tnone;
@@ -1679,28 +1741,46 @@ C_entries (c_ext)
         case ',':
           /* FALLTHRU */
         case '[':
+          if (definedef != dnone)
+            break;
           if (funcdef != finlist && funcdef != fignore)
             funcdef = fnone;
           if (structdef == stagseen)
             structdef = snone;
           break;
         case '(':
+          if (definedef != dnone)
+            break;
           switch (funcdef)
             {
             case ftagseen:
-              funcdef = finlist;
+              funcdef = fstartlist;
               break;
-            case finlist:
             case flistseen:
-              funcdef = fnone;
+              funcdef = finlist;
               break;
             }
+          parlev++;
           break;
         case ')':
-          if (funcdef == finlist)
-            funcdef = flistseen;
+          if (definedef != dnone)
+            break;
+          if (--parlev == 0)
+            {
+              switch (funcdef)
+                {
+                case fstartlist:
+                case finlist:
+                  funcdef = flistseen;
+                  break;
+                }
+            }
+          else if (parlev < 0)  /* can happen due to ill-conceived #if's. */
+            parlev = 0;
           break;
         case '{':
+          if (definedef != dnone)
+            break;
           if (typdef == ttypedseen)
             typdef = tinbody;
           switch (structdef)
@@ -1726,15 +1806,19 @@ C_entries (c_ext)
           cblev++;
           break;
         case '*':
-          if (funcdef == flistseen)
-            {
-              MAKE_TAG_FROM_OTH_LB (TRUE);
-              funcdef = fignore;
-            }
+          if (definedef != dnone)
+            break;
+          if (funcdef == fstartlist)
+            funcdef = fnone;    /* avoid tagging `foo' in `foo (*bar()) ()' */
           break;
         case '}':
+          if (definedef != dnone)
+            break;
           if (!noindentypedefs && lp == newlb.buffer + 1)
-            cblev = 0;  /* reset curly brace level if first column */
+            {
+              cblev = 0;        /* reset curly brace level if first column */
+              parlev = 0;       /* also reset paren level, just in case... */
+            }
           else if (cblev > 0)
             cblev--;
           if (cblev == 0)
@@ -1745,6 +1829,27 @@ C_entries (c_ext)
               (void) strcpy (structtag, "<error 2>");
             }
           break;
+        case '=':
+        case '#':
+        case '+':
+        case '-':
+        case '~':
+        case '&':
+        case '%':
+        case '/':
+        case '|':
+        case '^':
+        case '!':
+        case '<':
+        case '>':
+        case '.':
+        case '?':
+          if (definedef != dnone)
+            break;
+          /* These surely cannot follow a function tag. */
+          if (funcdef != finlist && funcdef != fignore)
+            funcdef = fnone;
+          break;
         case '\0':
           /* If a macro spans multiple lines don't reset its state. */
           if (quotednl)