Improve the parser error reporting

The parser now reports the correct file and line number for
errors. Additionally the @n location structure in rules now has a
filename member in addition to first_line. These members are useful
for adding location information in generated source.

3 files changed, 126 insertions, 34 deletions

diff --git a/src/nsgenbind-ast.c b/src/nsgenbind-ast.c
index 2915010..749d3e8 100644
--- a/src/nsgenbind-ast.c
+++ b/src/nsgenbind-ast.c
@@ -29,7 +29,7 @@ static FILE *genbind_parsetracef;
 extern int nsgenbind_debug;
 extern int nsgenbind__flex_debug;
 extern void nsgenbind_restart(FILE*);
-extern int nsgenbind_parse(struct genbind_node **genbind_ast);
+extern int nsgenbind_parse(char *filename, struct genbind_node **genbind_ast);
 
 /* terminal nodes have a value only */
 struct genbind_node {
@@ -515,12 +515,6 @@ FILE *genbindopen(const char *filename)
                         }
                         prevfilepath = strndup(filename,fulllen);
                 }
-#if 0
-                if (options->depfilehandle != NULL) {
-                        fprintf(options->depfilehandle, " \\\n\t%s",
-                                filename);
-                }
-#endif
                 return genfile;
         }
 
@@ -529,7 +523,7 @@ FILE *genbindopen(const char *filename)
                 fulllen = strlen(prevfilepath) + strlen(filename) + 2;
                 fullname = malloc(fulllen);
                 snprintf(fullname, fulllen, "%s/%s", prevfilepath, filename);
-                if (options->debug) {
+                if (options->verbose) {
                         printf("Attempting to open Genbind file %s\n", fullname);
                 }
                 genfile = fopen(fullname, "r");
@@ -537,12 +531,6 @@ FILE *genbindopen(const char *filename)
                         if (options->verbose) {
                                 printf("Opened Genbind file %s\n", fullname);
                         }
-#if 0
-                        if (options->depfilehandle != NULL) {
-                                fprintf(options->depfilehandle, " \\\n\t%s",
-                                        fullname);
-                        }
-#endif
                         free(fullname);
                         return genfile;
                 }
@@ -599,7 +587,7 @@ int genbind_parsefile(char *infilename, struct genbind_node **ast)
         nsgenbind_restart(infile);
 
         /* process binding */
-        ret = nsgenbind_parse(ast);
+        ret = nsgenbind_parse(infilename, ast);
 
         /* close tracefile if open */
         if (genbind_parsetracef != NULL) {
diff --git a/src/nsgenbind-lexer.l b/src/nsgenbind-lexer.l
index f32a948..af77368 100644
--- a/src/nsgenbind-lexer.l
+++ b/src/nsgenbind-lexer.l
@@ -15,9 +15,10 @@
 #include "nsgenbind-parser.h"
 #include "nsgenbind-ast.h"
 
-#define YY_USER_ACTION yylloc->first_line = yylloc->last_line; \
-    yylloc->first_column = yylloc->last_column + 1; \
-    yylloc->last_column += yyleng;
+#define YY_USER_ACTION                                             \
+        yylloc->first_line = yylloc->last_line = yylineno;         \
+        yylloc->first_column = yylloc->last_column + 1;            \
+        yylloc->last_column += yyleng;
 
 
 /* Ensure compatability with bison 2.6 and later */
@@ -29,6 +30,43 @@
 #define YYLTYPE NSGENBIND_LTYPE
 #endif
 
+static struct YYLTYPE *locations = NULL;
+
+static struct YYLTYPE *push_location(struct YYLTYPE *head,
+                                     struct YYLTYPE *loc,
+                                     const char *filename)
+{
+        struct YYLTYPE *res;
+        res = calloc(1, sizeof(struct YYLTYPE));
+        /* copy current location and line number */
+        *res = *loc;
+        res->start_line = yylineno;
+        res->next = head;
+
+        /* reset current location */
+        loc->first_line = loc->last_line = 1;
+        loc->first_column = loc->last_column = 1;
+        loc->filename = strdup(filename);
+        yylineno = 1;
+
+        return res;
+}
+
+static struct YYLTYPE *pop_location(struct YYLTYPE *head, struct YYLTYPE *loc)
+{
+        struct YYLTYPE *res = NULL;
+
+        if (head != NULL) {
+                res = head->next;
+                *loc = *head;
+                free(head);
+
+                yylineno = loc->start_line;
+        }
+        return res;
+}
+
+
 %}
 
 /* lexer options */
@@ -165,8 +203,10 @@ unsigned                return TOK_UNSIGNED;
                             fprintf(stderr, "Unable to open include %s\n", yytext);
                             exit(3);
                         }
-     			yypush_buffer_state(yy_create_buffer( yyin, YY_BUF_SIZE ));
-     
+
+                        locations = push_location(locations, yylloc, yytext);
+
+                        yypush_buffer_state(yy_create_buffer(yyin, YY_BUF_SIZE));
                         BEGIN(INITIAL);
                     }
 
@@ -178,9 +218,10 @@ unsigned                return TOK_UNSIGNED;
      			yypop_buffer_state();
      
                         if ( !YY_CURRENT_BUFFER ) {
-                            yyterminate();
+                                yyterminate();
                         } else {
-                            BEGIN(incl);
+                                locations = pop_location(locations, yylloc);
+                                BEGIN(incl);
                         }
 
                     }
diff --git a/src/nsgenbind-parser.y b/src/nsgenbind-parser.y
index 247a047..b52d0d0 100644
--- a/src/nsgenbind-parser.y
+++ b/src/nsgenbind-parser.y
@@ -1,4 +1,66 @@
-%{
+/* binding parser
+ *
+ * This file is part of nsgenbind.
+ * Licensed under the MIT License,
+ *                http://www.opensource.org/licenses/mit-license.php
+ * Copyright 2012 Vincent Sanders <vince@netsurf-browser.org>
+ */
+
+ /* bison prior to 2.4 cannot cope with %define api.pure so we use the
+  *  deprecated directive
+  */
+%pure-parser
+
+%locations
+
+%error-verbose
+ /* would use api.prefix but it needs to be different between bison
+  *  2.5 and 2.6
+  */
+
+%code requires {
+
+#define YYLTYPE YYLTYPE
+typedef struct YYLTYPE {
+        struct YYLTYPE *next;
+        int start_line;
+        char *filename;
+
+        int first_line;
+        int first_column;
+        int last_line;
+        int last_column;
+} YYLTYPE;
+
+
+#define YYLLOC_DEFAULT(Current, Rhs, N)                                \
+        do                                                             \
+                if (N) {                                               \
+          (Current).first_line   = YYRHSLOC (Rhs, 1).first_line;       \
+          (Current).first_column = YYRHSLOC (Rhs, 1).first_column;     \
+          (Current).last_line    = YYRHSLOC (Rhs, N).last_line;        \
+          (Current).last_column  = YYRHSLOC (Rhs, N).last_column;      \
+          (Current).filename     = YYRHSLOC (Rhs, 1).filename;         \
+          (Current).start_line   = YYRHSLOC (Rhs, 1).start_line;       \
+                } else { /* empty RHS */                               \
+          (Current).first_line   = (Current).last_line   =             \
+            YYRHSLOC (Rhs, 0).last_line;                               \
+          (Current).first_column = (Current).last_column =             \
+            YYRHSLOC (Rhs, 0).last_column;                             \
+          (Current).filename  = YYRHSLOC (Rhs, 0).filename;            \
+          (Current).start_line  = YYRHSLOC (Rhs, 0).start_line;        \
+                }                                                      \
+        while (0)
+
+}
+
+%initial-action {
+  yylloc.first_line   = yylloc.last_line   = 1;
+  yylloc.first_column = yylloc.last_column = 1;
+  yylloc.filename = filename;
+}
+
+%code {
 /* parser for the binding generation config file 
  *
  * This file is part of nsgenbind.
@@ -16,7 +78,6 @@
                   (Loc).first_line, (Loc).first_column,         \
                   (Loc).last_line,  (Loc).last_column)
 
-#include "nsgenbind-parser.h"
 #include "nsgenbind-lexer.h"
 #include "webidl-ast.h"
 #include "nsgenbind-ast.h"
@@ -24,12 +85,19 @@
 char *errtxt;
 
 static void nsgenbind_error(YYLTYPE *locp,
+                            char *filename,
                             struct genbind_node **genbind_ast,
                             const char *str)
 {
-        locp = locp;
+        int errlen;
+        errlen = snprintf(NULL, 0, "%s:%d:%s",
+                          locp->filename, locp->first_line, str);
+        errtxt = malloc(errlen + 1);
+        snprintf(errtxt, errlen + 1, "%s:%d:%s",
+                          locp->filename, locp->first_line, str);
+
         genbind_ast = genbind_ast;
-        errtxt = strdup(str);
+        filename = filename;
 }
 
 static struct genbind_node *
@@ -91,14 +159,9 @@ add_method(struct genbind_node **genbind_ast,
         return res_node;
 }
 
-%}
+}
 
-%locations
- /* bison prior to 2.4 cannot cope with %define api.pure so we use the
-  *  deprecated directive 
-  */
-%pure-parser
-%error-verbose
+%parse-param { char *filename }
 %parse-param { struct genbind_node **genbind_ast }
 
 %union
@@ -188,7 +251,7 @@ Statements:
         |
         error ';'
         {
-                fprintf(stderr, "%d: %s\n", yylloc.first_line, errtxt);
+                fprintf(stderr, "%s\n", errtxt);
                 free(errtxt);
                 YYABORT ;
         }