1 files changed, 139 insertions, 0 deletions

diff --git a/edify/parser.yy b/edify/parser.yy
new file mode 100644
index 000000000..098a6370a
--- /dev/null
+++ b/edify/parser.yy
@@ -0,0 +1,139 @@
+%{
+/*
+ * Copyright (C) 2009 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "expr.h"
+#include "yydefs.h"
+#include "parser.h"
+
+extern int gLine;
+extern int gColumn;
+
+void yyerror(Expr** root, int* error_count, const char* s);
+int yyparse(Expr** root, int* error_count);
+
+struct yy_buffer_state;
+void yy_switch_to_buffer(struct yy_buffer_state* new_buffer);
+struct yy_buffer_state* yy_scan_string(const char* yystr);
+
+%}
+
+%locations
+
+%union {
+    char* str;
+    Expr* expr;
+    struct {
+        int argc;
+        Expr** argv;
+    } args;
+}
+
+%token AND OR SUBSTR SUPERSTR EQ NE IF THEN ELSE ENDIF
+%token <str> STRING BAD
+%type <expr> expr
+%type <args> arglist
+
+%parse-param {Expr** root}
+%parse-param {int* error_count}
+%error-verbose
+
+/* declarations in increasing order of precedence */
+%left ';'
+%left ','
+%left OR
+%left AND
+%left EQ NE
+%left '+'
+%right '!'
+
+%%
+
+input:  expr           { *root = $1; }
+;
+
+expr:  STRING {
+    $$ = reinterpret_cast<Expr*>(malloc(sizeof(Expr)));
+    $$->fn = Literal;
+    $$->name = $1;
+    $$->argc = 0;
+    $$->argv = NULL;
+    $$->start = @$.start;
+    $$->end = @$.end;
+}
+|  '(' expr ')'                      { $$ = $2; $$->start=@$.start; $$->end=@$.end; }
+|  expr ';'                          { $$ = $1; $$->start=@1.start; $$->end=@1.end; }
+|  expr ';' expr                     { $$ = Build(SequenceFn, @$, 2, $1, $3); }
+|  error ';' expr                    { $$ = $3; $$->start=@$.start; $$->end=@$.end; }
+|  expr '+' expr                     { $$ = Build(ConcatFn, @$, 2, $1, $3); }
+|  expr EQ expr                      { $$ = Build(EqualityFn, @$, 2, $1, $3); }
+|  expr NE expr                      { $$ = Build(InequalityFn, @$, 2, $1, $3); }
+|  expr AND expr                     { $$ = Build(LogicalAndFn, @$, 2, $1, $3); }
+|  expr OR expr                      { $$ = Build(LogicalOrFn, @$, 2, $1, $3); }
+|  '!' expr                          { $$ = Build(LogicalNotFn, @$, 1, $2); }
+|  IF expr THEN expr ENDIF           { $$ = Build(IfElseFn, @$, 2, $2, $4); }
+|  IF expr THEN expr ELSE expr ENDIF { $$ = Build(IfElseFn, @$, 3, $2, $4, $6); }
+| STRING '(' arglist ')' {
+    $$ = reinterpret_cast<Expr*>(malloc(sizeof(Expr)));
+    $$->fn = FindFunction($1);
+    if ($$->fn == NULL) {
+        char buffer[256];
+        snprintf(buffer, sizeof(buffer), "unknown function \"%s\"", $1);
+        yyerror(root, error_count, buffer);
+        YYERROR;
+    }
+    $$->name = $1;
+    $$->argc = $3.argc;
+    $$->argv = $3.argv;
+    $$->start = @$.start;
+    $$->end = @$.end;
+}
+;
+
+arglist:    /* empty */ {
+    $$.argc = 0;
+    $$.argv = NULL;
+}
+| expr {
+    $$.argc = 1;
+    $$.argv = reinterpret_cast<Expr**>(malloc(sizeof(Expr*)));
+    $$.argv[0] = $1;
+}
+| arglist ',' expr {
+    $$.argc = $1.argc + 1;
+    $$.argv = reinterpret_cast<Expr**>(realloc($$.argv, $$.argc * sizeof(Expr*)));
+    $$.argv[$$.argc-1] = $3;
+}
+;
+
+%%
+
+void yyerror(Expr** root, int* error_count, const char* s) {
+  if (strlen(s) == 0) {
+    s = "syntax error";
+  }
+  printf("line %d col %d: %s\n", gLine, gColumn, s);
+  ++*error_count;
+}
+
+int parse_string(const char* str, Expr** root, int* error_count) {
+    yy_switch_to_buffer(yy_scan_string(str));
+    return yyparse(root, error_count);
+}