Improve parser. Allow users to declare aliases to other symbols.

The latter feature is useful for declaring reserved symbols such
as __restrict or __inline, e.g. --symbol __restrict:=restrict
instructs cflow to treat `__restrict' exactly as `restrict'.

* src/Makefile.am: Minor fix in rule for flowgraph.
* src/c.l (init_tokens): New function, separated from
init_lex.
Install qualifiers.
* src/cflow.h (symbol_alias): New flag.
(symbol)<alias>: New member.
(INSTALL_DEFAULT,INSTALL_OVERWRITE)
(INSTALL_CHECK_LOCAL,INSTALL_UNIT_LOCAL): New defines.
* src/cflow.rc: Rewrite for use with --cpp='gcc -E'
* src/main.c (symbol_override): Extend syntax to allow for defining
aliases to other tokens (--symbol __inline:=inline).
* src/parser.c (print_token): print qualifiers and ops.
(file_error): Change signature. All uses changed.
(save_token): Improve output spacing.
(skip_balanced): Treat LBRACE0 and RBRACE0 as { and }.
(is_function): allow for qualifiers and wrappers before
defintion.
(parse_function_declaration): Remove PARM_WRAPPER case: it
is taken care of by the caller.
(fake_struct): leave when '(' is encountered.
(parse_variable_declaration): Allow for qualifiers before
the identifier.
(skip_struct): Use skip_balanced.
(dcl): Handle wrappers. Leave if a semicolon is encountered.
(dirdcl): Optimize handing of wrapper.
(maybe_parm_list): Handle qualifiers.
(declare): allow for wrappers.
(declare_type): Pass INSTALL_UNIT_LOCAL as a flag to install.
* src/symbol.c (lookup): Argument is const now.
(install): Change semantics of the 2nd argument.
(install_ident): Change the call to install accordingly.
* tests/nfparg.at: Change spacing to reflect changes to
save_token.

8 files changed, 235 insertions, 157 deletions

diff --git a/src/Makefile.am b/src/Makefile.am
index 05acd30..f4736d7 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -44,11 +44,12 @@ AM_CPPFLAGS=-DLOCALEDIR=\"$(localedir)\"
 AM_LFLAGS=-dvp
 EXTRA_DIST=cflow.rc
 
+CFLOW=$(abs_builddir)/cflow
 CFLOW_FLAGS=-i^s --brief
 cflow_CFLOW_INPUT=$(cflow_OBJECTS:.@OBJEXT@=.c)
 cflow.cflow: $(cflow_CFLOW_INPUT) cflow.rc Makefile
-        CFLOWRC=$(top_srcdir)/src/cflow.rc \
-         cflow -o$@ $(CFLOW_FLAGS) $(DEFS) \
-                    $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) \
-                    $(CPPFLAGS) \
+        $(AM_V_GEN)CFLOWRC=$(top_srcdir)/src/cflow.rc \
+         $(CFLOW) -o$@ --cpp="$(CC) -E" $(CFLOW_FLAGS) $(DEFS) \
+                  $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) \
+                  $(CPPFLAGS) \
          $(cflow_CFLOW_INPUT)
diff --git a/src/c.l b/src/c.l
index be14004..f3467e8 100644
--- a/src/c.l
+++ b/src/c.l
@@ -75,7 +75,6 @@ auto                 /* ignored */;
 extern               return EXTERN; 
 static               return STATIC;
 typedef              return TYPEDEF;
-inline               {yylval.str = "inline"; return QUALIFIER; }
 struct               {yylval.str = "struct"; return STRUCT;}
 union                {yylval.str = "union"; return STRUCT;}
 enum                 {yylval.str = "enum"; return STRUCT;}
@@ -85,30 +84,39 @@ enum                 {yylval.str = "enum"; return STRUCT;}
      /* Operators
       *
       */
-"->"   |
-"."                  return MEMBER_OF;
-"*="   |                 
-"/="   |                 
-"%="   |                 
-"+="   |                 
-"-="   |                 
-"<<="  |                 
-">>="  |                 
-"&="   |                 
-"|="   |                 
-"^="   |                 
-"||"   |                 
-"&&"   |                 
-"=="   |                 
-"!="   |                 
-">="   |                 
-">"    |                 
-"<="   |                 
-"<"    |                 
-"<<"   |                 
-">>"   |                 
-"++"   |                 
-"--"                     return OP;
+"->"                 {yylval.str = "->"; return MEMBER_OF;}
+"."                  {yylval.str = "."; return MEMBER_OF;}
+"*="                 {yylval.str = "*="; return OP;}
+"/="                 {yylval.str = "/="; return OP;}
+"/"                  {yylval.str = "/"; return OP;}
+"%="                 {yylval.str = "%="; return OP;}
+"%"                  {yylval.str = "%"; return OP;}
+"+="                 {yylval.str = "+="; return OP;}
+"+"                  {yylval.str = "+"; return OP;}
+"-="                 {yylval.str = "-="; return OP;}
+"-"                  {yylval.str = "-"; return OP;}
+"<<="                {yylval.str = "<<="; return OP;}
+">>="                {yylval.str = ">>="; return OP;}
+"&="                 {yylval.str = "&="; return OP;}
+"|="                 {yylval.str = "|="; return OP;}
+"^="                 {yylval.str = "^="; return OP;}
+"^"                  {yylval.str = "^"; return OP;}
+"||"                 {yylval.str = "||"; return OP;}
+"|"                  {yylval.str = "|"; return OP;}
+"&&"                 {yylval.str = "&&"; return OP;}
+"&"                  {yylval.str = "&"; return OP;}
+"=="                 {yylval.str = "=="; return OP;}
+"="                  {yylval.str = "="; return '=';}
+"!="                 {yylval.str = "!="; return OP;}
+"!"                  {yylval.str = "!"; return OP;}
+">="                 {yylval.str = ">="; return OP;}
+">"                  {yylval.str = ">"; return OP;}
+"<="                 {yylval.str = "<="; return OP;}
+"<"                  {yylval.str = "<"; return OP;}    
+"<<"                 {yylval.str = "<<"; return OP;}
+">>"                 {yylval.str = ">>"; return OP;}
+"++"                 {yylval.str = "++"; return OP;}
+"--"                 {yylval.str = "--"; return OP;}
 '.'  |
 '\\.' |
 '\\[0-7]{2,3}' |
@@ -181,50 +189,67 @@ static char *keywords[] = {
 
 static char *types[] = {
     "char",
-    "const",
     "double",
     "float",
     "int",
+    "void",
+};
+
+static char *qualifiers[] = {
     "long",
+    "const",
     "register",
     "restrict",
     "short",
     "signed",
     "unsigned",
-    "void",
     "volatile",
+    "inline"
 };
 
 void
-init_lex(int debug_level)
+init_tokens()
 {
      int i;
      Symbol *sp;
     
-     yy_flex_debug = debug_level;
-     
-     obstack_init(&string_stk);
-
      for (i = 0; i < NUMITEMS(keywords); i++) {
-          sp = install(keywords[i], 0);
+          sp = install(keywords[i], INSTALL_OVERWRITE);
           sp->type = SymToken;
           sp->token_type = WORD;
      }
      
      for (i = 0; i < NUMITEMS(types); i++) {
-          sp = install(types[i], 0);
+          sp = install(types[i], INSTALL_OVERWRITE);
           sp->type = SymToken;
           sp->token_type = TYPE;
           sp->source = NULL;
           sp->def_line = -1;
           sp->ref_line = NULL;
      }  
-     sp = install("...", 0);
+
+     for (i = 0; i < NUMITEMS(qualifiers); i++) {
+          sp = install(qualifiers[i], INSTALL_OVERWRITE);
+          sp->type = SymToken;
+          sp->token_type = QUALIFIER;
+          sp->source = NULL;
+          sp->def_line = -1;
+          sp->ref_line = NULL;
+     }  
+     sp = install("...", INSTALL_OVERWRITE);
      sp->type = SymToken;
      sp->token_type = IDENTIFIER;
      sp->source = NULL;
      sp->def_line = -1;
      sp->ref_line = NULL;
+}       
+
+void
+init_lex(int debug_level)
+{
+     yy_flex_debug = debug_level;
+     obstack_init(&string_stk);
+     init_tokens();
 }
 
 int
diff --git a/src/cflow.h b/src/cflow.h
index 1749ada..07cc8cf 100644
--- a/src/cflow.h
+++ b/src/cflow.h
@@ -83,7 +83,8 @@ enum symbol_flag {
      symbol_none,
      symbol_temp,                  /* Temporary symbol. Must be deleted after
                                       processing of the current module */
-     symbol_parm                   /* Parameter */
+     symbol_parm,                  /* Parameter */
+     symbol_alias                  /* Alias to another symbol */
 };
 
 typedef struct symbol Symbol;
@@ -96,7 +97,11 @@ struct symbol {
      enum symtype type;            /* Type of the symbol */
      char *name;                   /* Identifier */
      enum symbol_flag flag;        /* Specific flag */
-     
+     struct symbol *alias;         /* Points to the aliased symbol if
+                                      type==SymToken and flag==symbol_alias.
+                                      In this case, the rest of the structure
+                                      is ignored */
+        
      int active;                   /* Set to 1 when the symbol's subtree is
                                       being processed, prevent recursion */
      int expand_line;              /* Output line when this symbol was first
@@ -165,7 +170,12 @@ extern int token_stack_increase;
 extern int symbol_count;
 extern unsigned input_file_count;
 
-Symbol *lookup(char*);
+#define INSTALL_DEFAULT     0x00
+#define INSTALL_OVERWRITE   0x01
+#define INSTALL_CHECK_LOCAL 0x02
+#define INSTALL_UNIT_LOCAL  0x04
+
+Symbol *lookup(const char*);
 Symbol *install(char*, int);
 Symbol *install_ident(char *name, enum storage storage);