better error handling, simplified EOI handling with improved input module

diff --git a/lang/m2/comp/LLlex.c b/lang/m2/comp/LLlex.c
index 99940f1..83be7d2 100644 (file)
--- a/lang/m2/comp/LLlex.c
+++ b/lang/m2/comp/LLlex.c
@@ -41,7 +41,6 @@ int           ForeignFlag;
 extern int     cntlines;
 #endif
 
-static int     eofseen;
 extern char    options[];
 
 STATIC
@@ -90,7 +89,7 @@ SkipComment()
                }
        }
        for (;;) {
-               if (class(ch) == STNL) {
+               if (!(ch & 0200) && class(ch) == STNL) {
                        LineNumber++;
 #ifdef DEBUG
                        cntlines++;
@@ -111,6 +110,7 @@ SkipComment()
                }
                else if (ch == EOI) {
                        lexerror("unterminated comment");
+                       PushBack();
                        break;
                }
                LoadChar(ch);
@@ -131,7 +131,7 @@ GetString(upto)
        len = ISTRSIZE;
        str->s_str = p = Malloc((unsigned int) ISTRSIZE);
        while (LoadChar(ch), ch != upto)        {
-               if (class(ch) == STNL)  {
+               if (!(ch & 0200) && class(ch) == STNL)  {
                        lexerror("newline in string");
                        LineNumber++;
 #ifdef DEBUG
@@ -169,17 +169,8 @@ getch()
 {
        register int ch;
 
-       for (;;) {
-               LoadChar(ch);
-               if ((ch & 0200) && ch != EOI) {
-                       error("non-ascii '\\%03o' read", ch & 0377);
-                       continue;
-               }
-               break;
-       }
-       if (ch == EOI) {
-               eofseen = 1;
-               return '\n';
+       while (LoadChar(ch), (ch & 0200) && ch != EOI) {
+               error("non-ascii '\\%03o' read", ch & 0377);
        }
        return ch;
 }
@@ -188,7 +179,7 @@ CheckForLineDirective()
 {
        register int ch = getch();
        register int    i = 0;
-       char            buf[IDFSIZE + 2];
+       char            buf[IDFSIZE];
        register char   *c = buf;
 
 
@@ -201,7 +192,7 @@ CheckForLineDirective()
                 * Do not skip newlines
                 */
                ch = getch();
-               if (class(ch) == STNL) {
+               if (class(ch) == STNL || class(ch) == STEOI) {
                        LineNumber++;
                        error(s_error);
                        return;
@@ -211,12 +202,14 @@ CheckForLineDirective()
                i = i*10 + (ch - '0');
                ch = getch();
        }
-       while (ch != '"' && class(ch) != STNL) ch = getch();
+       while (ch != '"' && class(ch) != STNL && class(ch) != STEOI)
+               ch = getch();
        if (ch == '"') {
                c = buf;
                do {
-                       *c++ = ch = getch();
-                       if (class(ch) == STNL) {
+                       ch = getch();
+                       if (c < &buf[IDFSIZE]) *c++ = ch;
+                       if (class(ch) == STNL || class(ch) == STEOI) {
                                LineNumber++;
                                error(s_error);
                                return;
@@ -225,28 +218,21 @@ CheckForLineDirective()
                *--c = '\0';
                do {
                        ch = getch();
-               } while (class(ch) != STNL);
+               } while (class(ch) != STNL && class(ch) != STEOI);
                /*
                 * Remember the file name
                 */
-               if (!eofseen && strcmp(FileName,buf)) {
+               if (class(ch) == STNL && strcmp(FileName,buf)) {
                        FileName = Salloc(buf,(unsigned) strlen(buf) + 1);
                }
        }
-       if (eofseen) {
+       if (class(ch) == STEOI) {
                error(s_error);
                return;
        }
        LineNumber = i;
 }
 
-static
-UnloadChar(ch)
-{
-       if (ch == EOI) eofseen = 1;
-       else PushBack();
-}
-       
 int
 LLlex()
 {
@@ -265,20 +251,8 @@ LLlex()
                return tk->tk_symb;
        }
 
-again1:
-       if (eofseen) {
-               eofseen = 0;
-               ch = EOI;
-       }
-       else {
 again:
-               LoadChar(ch);
-               if ((ch & 0200) && ch != EOI) {
-                       error("non-ascii '\\%03o' read", ch & 0377);
-                       goto again;
-               }
-       }
-
+       ch = getch();
        tk->tk_lineno = LineNumber;
 
        switch (class(ch))      {
@@ -289,7 +263,7 @@ again:
                cntlines++;
 #endif
                CheckForLineDirective();
-               goto again1;
+               goto again;
 
        case STSKIP:
                goto again;
@@ -308,7 +282,7 @@ again:
                                SkipComment();
                                goto again;
                        }
-                       UnloadChar(nch);
+                       PushBack();
                }
                if (ch == '&') return tk->tk_symb = AND;
                if (ch == '~') return tk->tk_symb = NOT;
@@ -348,7 +322,7 @@ again:
                default :
                        crash("(LLlex, STCOMP)");
                }
-               UnloadChar(nch);
+               PushBack();
                return tk->tk_symb = ch;
 
        case STIDF:
@@ -364,7 +338,7 @@ again:
                        }
                } while(in_idf(ch));
 
-               UnloadChar(ch);
+               PushBack();
                *tag = '\0';
                if (*(tag - 1) == '_') {
                        lexerror("last character of an identifier may not be an underscore");
@@ -436,7 +410,7 @@ again:
                                else {
                                        state = End;
                                        if (ch == 'H') base = 16;
-                                       else UnloadChar(ch);
+                                       else PushBack();
                                }
                                break;
 
@@ -462,7 +436,7 @@ again:
                                state = End;
                                if (ch != 'H') {
                                        lexerror("H expected after hex number");
-                                       UnloadChar(ch);
+                                       PushBack();
                                }
                                break;
 
@@ -478,7 +452,7 @@ again:
                                        state = Hex;
                                        break;
                                }
-                               UnloadChar(ch);
+                               PushBack();
                                ch = *--np;
                                *np++ = '\0';
                                /* Fall through */
@@ -582,7 +556,7 @@ lexwarning(W_ORDINARY, "overflow in constant");
                                LoadChar(ch);
                                if (!(ch == '+' || ch == '-' || is_dig(ch)))
                                        goto noscale;
-                               UnloadChar(ch);
+                               PushBack();
                        }
                        if (np < &buf[NUMSIZE]) *np++ = 'E';
                        LoadChar(ch);
@@ -605,7 +579,7 @@ lexwarning(W_ORDINARY, "overflow in constant");
 
 noscale:
                *np++ = '\0';
-               UnloadChar(ch);
+               PushBack();
 
                if (np >= &buf[NUMSIZE]) {
                        tk->TOK_REL = Salloc("0.0", 5);

diff --git a/lang/m2/comp/Makefile b/lang/m2/comp/Makefile
index 170d427..183ee1c 100644 (file)
--- a/lang/m2/comp/Makefile
+++ b/lang/m2/comp/Makefile
@@ -166,13 +166,13 @@ $(CURRDIR)main:   $(OBJ) $(CURRDIR)Makefile
        $(CC) $(LDFLAGS) $(OBJ) $(OLIBS) -o $(CURRDIR)main
        -size $(CURRDIR)main
 
-$(CURRDIR)omain:       $(OBJ) $(CURRDIR)Makefile
-       $(CC) $(LDFLAGS) $(OBJ) $(OLIBS) -o $(CURRDIR)omain
-       size $(CURRDIR)omain
+$(CURRDIR)omain:       $(OBJ) #$(CURRDIR)Makefile
+       #$(CC) $(LDFLAGS) $(OBJ) $(OLIBS) -o $(CURRDIR)omain
+       #size $(CURRDIR)omain
 
-$(CURRDIR)cemain:      $(OBJ) $(CURRDIR)Makefile
-       $(CC) $(LDFLAGS) $(OBJ) $(OLIBS) -o $(CURRDIR)cemain 
-       size $(CURRDIR)cemain
+$(CURRDIR)cemain:      $(OBJ) #$(CURRDIR)Makefile
+       #$(CC) $(LDFLAGS) $(OBJ) $(OLIBS) -o $(CURRDIR)cemain 
+       #size $(CURRDIR)cemain
 
 
 #AUTOAUTOAUTOAUTOAUTOAUTOAUTOAUTO

diff --git a/lang/m2/comp/def.c b/lang/m2/comp/def.c
index 260f2c5..347c59a 100644 (file)
--- a/lang/m2/comp/def.c
+++ b/lang/m2/comp/def.c
@@ -120,8 +120,10 @@ define(id, scope, kind)
           ) {
                switch(df->df_kind) {
                case D_INUSE:
-                       if (kind != D_INUSE) {
+                       if (kind != D_INUSE && kind != D_ERROR) {
                                error("identifier \"%s\" already used; may not be redefined in this scope", df->df_idf->id_text);
+                               df->df_kind = D_ERROR;
+                               break;
                        }
                        return df;
 
@@ -158,12 +160,9 @@ define(id, scope, kind)
                        break;
                case D_FORWTYPE:
                        if (kind & (D_FORWTYPE|D_TYPE)) return df;
-                       else {
-                               error("identifier \"%s\" must be a type",
-                                       id->id_text);
-                       }
-                       return df;
-
+                       error("identifier \"%s\" must be a type", id->id_text);
+                       df->df_kind = D_ERROR;
+                       break;
                case D_FORWARD:
                        /* A forward reference, for which we may now have
                           found a definition.
@@ -171,29 +170,24 @@ define(id, scope, kind)
                        if (! (kind & (D_FORWARD | D_FORWMODULE))) {
                                FreeNode(df->for_node);
                        }
-
-                       /* Fall through */
-
-               case D_ERROR:
-                       /* A definition generated by the compiler, because
-                          it found an error. Maybe, the user gives a
-                          definition after all.
-                       */
-                       if (kind & (D_TYPE|D_PROCEDURE|D_CONST)) {
-                               df->df_flags = D_DEFINED;
-                       }
-                       df->df_kind = kind;
-                       return df;
+                       df->df_kind = D_ERROR;  /* avoiding error message */
+                       break;
                }
 
-               if (kind != D_ERROR) {
+               if (kind != D_ERROR && df->df_kind != D_ERROR) {
                        /* Avoid spurious error messages
                        */
                        error("identifier \"%s\" already declared",
                              id->id_text);
                }
+               if (df->df_scope == scope || df->df_kind == D_ERROR) {
+                       df->df_kind = kind;
+                       if (kind & (D_TYPE|D_PROCEDURE|D_CONST)) {
+                               df->df_flags = D_DEFINED;
+                       }
 
-               return df;
+                       return df;
+               }
        }
 
        return MkDef(id, scope, kind);