Minor changes.

* mfd/gram.y: Improve module ending rules.
* mfd/lex.l: Add more comments.
(lex_buffer_push): Rename to inctx_push.
(lex_buffer_pop): Rename to inctx_pop.
* mfd/mailfromd.h (module_push): Remove.
* mfd/symbols.c: Mark module_ functions
as statics.

4 files changed, 58 insertions, 38 deletions

diff --git a/mfd/gram.y b/mfd/gram.y
index 2b8c6bbb..94b08f81 100644
--- a/mfd/gram.y
+++ b/mfd/gram.y
@@ -490,11 +490,7 @@ input      : program
            ;
 
 program    : decllist
-           | moddecl decllist modend
-             {
-		     $$ = $2;
-	     }
-           | moddecl decllist
+           | moddecl decllist bye
              {
 		     $$ = $2;
 	     }
@@ -533,7 +529,7 @@ modcntl    : require
              {
 		     $$.head = $$.tail = NULL;
 	     }
-           | require T_MODBEG opt_moddecl decllist modend
+           | require T_MODBEG opt_moddecl decllist bye T_MODEND
              {
 		     $$ = $4;
 		     pop_top_module();
@@ -581,11 +577,11 @@ require    : T_REQUIRE literal
 	     }
            ;
 
-modend     : T_BYE
+bye        : /* empty */
+           | T_BYE
              {
 		     lex_bye();
 	     }
-           | T_MODEND
            ;
 
 imports    : literal
diff --git a/mfd/lex.l b/mfd/lex.l
index ba467503..30ebb935 100644
--- a/mfd/lex.l
+++ b/mfd/lex.l
@@ -67,26 +67,34 @@ get_locus()
 #define keyword(kw) (yylval.locus = locus,(kw))
 
 
-#define INCTX_MODULE   0x1
-#define INCTX_HADINPUT 0x2
-
-/* Input stack support */
-struct inctx {         /* input context structure */
-	struct inctx *parent;
-	struct locus locus;
-	struct input_file_ident id;
-	FILE *file;
-	pid_t pp_pid;         /* Preprocessor pid, if used */
-	int inctx_flags;
-	YY_BUFFER_STATE buf;  /* Lex buffer state */
+/* Input context flags */
+#define INCTX_MODULE   0x1  /* current input is a MFL module */
+#define INCTX_HADINPUT 0x2  /* some statements has already been processed */
+
+/* Input context stack */
+struct inctx {                     /* input context structure */
+	struct inctx *parent;      /* parent context */
+	struct locus locus;        /* locus where the context was pushed */
+	struct input_file_ident id;/* file id structure to prevent recursion */
+	FILE *file;                /* saved yyin */ 
+	pid_t pp_pid;              /* preprocessor pid, if used */
+	int inctx_flags;           /* input context flags */ 
+	YY_BUFFER_STATE buf;       /* lex buffer state */
 };
 
-struct inctx *inctx_tos;
-static pid_t pp_pid; /* Preprocessor pid */
+struct inctx *inctx_tos;           /* stack of input contexts */
+
+/* Current input context: */
+static pid_t pp_pid;               /* preprocessor pid */
 static struct input_file_ident input_file_id;
-static int inctx_flags;
+static int inctx_flags;            /* input context flags */
+
+/* If not 0, emit_token keeps a token that yylex must return on the
+   next call. See YY_USER_ACTION below. */
 static int emit_token;
 
+/* Find on stack an input context that matches the given file id.
+   Return pointer to the context. */
 struct inctx *
 inctx_locate(struct input_file_ident *id)
 {
@@ -99,9 +107,9 @@ inctx_locate(struct input_file_ident *id)
 	return ctx;
 }
 	
-	
+/* Push input context */	
 static void
-lex_buffer_push()
+inctx_push()
 {
 	struct inctx *ctx = xmalloc(sizeof(*ctx));
 
@@ -115,8 +123,10 @@ lex_buffer_push()
 	inctx_tos = ctx;
 }
 
+/* Pop input context from the top of the stack into the current
+   input context. Return 1 if there are no more contexts left. */
 int
-lex_buffer_pop()
+inctx_pop()
 {
 	struct inctx *ctx = inctx_tos;
 	
@@ -136,6 +146,8 @@ lex_buffer_pop()
 	return 0;
 }
 
+/* Setup the scanner for input from the file NAME. Return 0 on success,
+   and an appropriate EX_ code on error. See lex_new_source below. */
 static int
 lex_new_source_0(const char *name)
 {
@@ -162,6 +174,9 @@ lex_new_source_0(const char *name)
 	return EX_OK;
 }
 
+/* Save the current input context on stack and set up the scanner for
+   input from the file NAME. Return 0 on success,
+   and an appropriate EX_ code on error. */
 int
 lex_new_source(const char *name, int flag)
 {
@@ -196,10 +211,10 @@ lex_new_source(const char *name, int flag)
 		return 0;
 
 	if (yyin)
-		lex_buffer_push();
+		inctx_push();
 	rc = lex_new_source_0(name);
 	if (rc)
-		lex_buffer_pop();
+		inctx_pop();
 	else {
 		input_file_id = id;
 		if (flag == LEX_MODULE) {
@@ -212,6 +227,8 @@ lex_new_source(const char *name, int flag)
 }
 
 
+/* Return constant or variable token corresponding to the current
+   value of yylval.literal->text. */
 static int
 variable_or_const()
 {
@@ -245,14 +262,19 @@ variable_or_const()
 	return T_VARIABLE;
 }
 	
+/* Advance locus to the next line */
 void
 advance_line()
 {
 	++locus.line;
 }
 
+/* Same as BEGIN, but also saves the current locus. It is then used
+   to report unclosed constructs at the end of file. */
 #define BEGIN_X(s) do { BEGIN(s); start_locus = locus; } while(0)
 
+/* If emit_token is not 0, push back current input and return the value
+   of emit_token. Clear emit_token before returning. */
 #define YY_USER_ACTION							\
 	if (emit_token) {						\
 		int tok = emit_token;					\
@@ -264,6 +286,7 @@ advance_line()
 		return tok;						\
 	}								\
 
+/* Read next input chunk. */
 #define YY_INPUT(buf,result,max_size)					\
 	if (yyin == NULL)						\
 		result = YY_NULL;					\
@@ -271,6 +294,8 @@ advance_line()
 		 && ferror(yyin))					\
 		YY_FATAL_ERROR("input in flex scanner failed");
 
+/* Redeclare main entry point. Actual yylex is defined in the code section
+   below. */
 #define YY_DECL static int lexscan(void)
 %}
 
@@ -937,7 +962,7 @@ lex_close_source()
 	case QML:
 		parse_error_locus(&start_locus, _("end of file in string"));
 	}
-	return lex_buffer_pop();
+	return inctx_pop();
 }
 
 void
diff --git a/mfd/mailfromd.h b/mfd/mailfromd.h
index 5cdb34f0..965bfd94 100644
--- a/mfd/mailfromd.h
+++ b/mfd/mailfromd.h
@@ -757,7 +757,6 @@ int set_top_module(const char *name, const char *file,
 		   struct import_rule *import_rules,
 		   const struct locus *locus);
 void pop_top_module(void);
-void module_push(struct module *mod);
 void collect_modules(struct module ***pmodv, size_t *pmodc);
 
 
diff --git a/mfd/symbols.c b/mfd/symbols.c
index e4b61f84..75c81484 100644
--- a/mfd/symbols.c
+++ b/mfd/symbols.c
@@ -447,7 +447,7 @@ module_import_symbols(struct module *dst, struct module *src,
 struct module *top_module;
 struct module_list *module_stack;
 
-void
+static void
 module_init(struct module *mod, const char *name, const char *file)
 {
 	mod->name = mf_strdup(name);
@@ -468,7 +468,7 @@ module_init(struct module *mod, const char *name, const char *file)
 	mod->incl_sources = NULL;
 }
 
-struct module *
+static struct module *
 module_create(const char *name, const char *file)
 {
 	struct module *mod = alloc_entry(sizeof(*mod));
@@ -476,7 +476,7 @@ module_create(const char *name, const char *file)
 	return mod;
 }
 
-void
+static void
 module_free(struct module *mod)
 {
 	int i;
@@ -487,7 +487,7 @@ module_free(struct module *mod)
 	mu_list_destroy(&mod->incl_sources);
 }	
 
-void
+static void
 module_add_submodule(struct module *mod, struct module *submod)
 {
 	struct module_list *p = alloc_entry(sizeof(*p));
@@ -500,7 +500,7 @@ module_add_submodule(struct module *mod, struct module *submod)
 	mod->submodule_tail = p;
 }
 
-int
+static int
 module_has_submodule(struct module *mod, struct module *submod)
 {
 	struct module_list *p;
@@ -510,7 +510,7 @@ module_has_submodule(struct module *mod, struct module *submod)
 	return 0;
 }
 
-void
+static void
 module_push(struct module *mod)
 {
 	struct module_list *p = alloc_entry(sizeof(*p));
@@ -519,7 +519,7 @@ module_push(struct module *mod)
 	module_stack = p;
 }
 
-struct module *
+static struct module *
 module_pop()
 {
 	struct module_list *p = module_stack;
@@ -609,7 +609,7 @@ collect_modules(struct module ***pmodv, size_t *pmodc)
 }
 
 
-void
+static void
 free_module_entry(void *ptr)
 {
 	module_free((struct module *)ptr);