Code

frontend: Improved parser error reporting.
[sysdb.git] / src / frontend / grammar.y
index 08f8414142f58123dd63c9cf7c991d96c6bff5ff..ab9345e22c80272b6cbd4b84b0fd7ce4472fda87 100644 (file)
 #include "utils/error.h"
 #include "utils/llist.h"
 
+#include <assert.h>
+
 #include <stdio.h>
 #include <string.h>
 
+/*
+ * private helper functions
+ */
+
+static sdb_store_matcher_t *
+name_iter_matcher(int m_type, int type, const char *cmp,
+               sdb_store_expr_t *expr);
+
+/*
+ * public API
+ */
+
 int
 sdb_fe_yylex(YYSTYPE *yylval, YYLTYPE *yylloc, sdb_fe_yyscan_t yyscanner);
 
@@ -49,6 +63,8 @@ sdb_fe_yyget_extra(sdb_fe_yyscan_t scanner);
 
 void
 sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
+void
+sdb_fe_yyerrorf(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *fmt, ...);
 
 /* quick access to the current parse tree */
 #define pt sdb_fe_yyget_extra(scanner)->parsetree
@@ -56,6 +72,15 @@ sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
 /* quick access to the parser mode */
 #define parser_mode sdb_fe_yyget_extra(scanner)->mode
 
+/* quick access to the parser's error buffer */
+#define errbuf sdb_fe_yyget_extra(scanner)->errbuf
+
+#define MODE_TO_STRING(m) \
+       (((m) == SDB_PARSE_DEFAULT) ? "statement" \
+               : ((m) == SDB_PARSE_COND) ? "condition" \
+               : ((m) == SDB_PARSE_EXPR) ? "expression" \
+               : "UNKNOWN")
+
 %}
 
 %pure-parser
@@ -69,6 +94,7 @@ sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
 %union {
        const char *sstr; /* static string */
        char *str;
+       int integer;
 
        sdb_data_t data;
        sdb_time_t datetime;
@@ -86,9 +112,13 @@ sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
 
 %token AND OR IS NOT MATCHING FILTER
 %token CMP_EQUAL CMP_NEQUAL CMP_REGEX CMP_NREGEX
-%token CMP_LT CMP_LE CMP_GE CMP_GT
+%token CMP_LT CMP_LE CMP_GE CMP_GT ALL ANY IN
 %token CONCAT
 
+%token HOST_T HOSTS_T SERVICE_T SERVICES_T METRIC_T METRICS_T
+%token ATTRIBUTE_T ATTRIBUTES_T
+%token NAME_T LAST_UPDATE_T AGE_T INTERVAL_T BACKEND_T
+
 %token START END
 
 /* NULL token */
@@ -109,6 +139,7 @@ sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
 %left CMP_EQUAL CMP_NEQUAL
 %left CMP_LT CMP_LE CMP_GE CMP_GT
 %nonassoc CMP_REGEX CMP_NREGEX
+%nonassoc IN
 %left CONCAT
 %nonassoc IS
 %left '+' '-'
@@ -132,7 +163,11 @@ sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
 
 %type <expr> expression
 
-%type <sstr> op
+%type <integer> object_type object_type_plural
+%type <integer> iterable
+%type <integer> field
+
+%type <sstr> cmp
 
 %type <data> data
        interval interval_elem
@@ -142,17 +177,18 @@ sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg);
 
 %destructor { free($$); } <str>
 %destructor { sdb_object_deref(SDB_OBJ($$)); } <node> <m> <expr>
+%destructor { sdb_data_free_datum(&$$); } <data>
 
 %%
 
 statements:
        statements ';' statement
                {
-                       /* only accept this in default parse mode */
+                       /* only accepted in default parse mode */
                        if (parser_mode != SDB_PARSE_DEFAULT) {
-                               sdb_fe_yyerror(&yylloc, scanner,
+                               sdb_fe_yyerrorf(&yylloc, scanner,
                                                YY_("syntax error, unexpected statement, "
-                                                       "expecting condition"));
+                                                       "expecting %s"), MODE_TO_STRING(parser_mode));
                                sdb_object_deref(SDB_OBJ($3));
                                YYABORT;
                        }
@@ -165,11 +201,11 @@ statements:
        |
        statement
                {
-                       /* only accept this in default parse mode */
+                       /* only accepted in default parse mode */
                        if (parser_mode != SDB_PARSE_DEFAULT) {
-                               sdb_fe_yyerror(&yylloc, scanner,
+                               sdb_fe_yyerrorf(&yylloc, scanner,
                                                YY_("syntax error, unexpected statement, "
-                                                       "expecting condition"));
+                                                       "expecting %s"), MODE_TO_STRING(parser_mode));
                                sdb_object_deref(SDB_OBJ($1));
                                YYABORT;
                        }
@@ -182,11 +218,11 @@ statements:
        |
        condition
                {
-                       /* only accept this in condition parse mode */
+                       /* only accepted in condition parse mode */
                        if (! (parser_mode & SDB_PARSE_COND)) {
-                               sdb_fe_yyerror(&yylloc, scanner,
+                               sdb_fe_yyerrorf(&yylloc, scanner,
                                                YY_("syntax error, unexpected condition, "
-                                                       "expecting statement"));
+                                                       "expecting %s"), MODE_TO_STRING(parser_mode));
                                sdb_object_deref(SDB_OBJ($1));
                                YYABORT;
                        }
@@ -196,6 +232,29 @@ statements:
                                sdb_object_deref(SDB_OBJ($1));
                        }
                }
+       |
+       expression
+               {
+                       /* only accepted in expression parse mode */
+                       if (! (parser_mode & SDB_PARSE_EXPR)) {
+                               sdb_fe_yyerrorf(&yylloc, scanner,
+                                               YY_("syntax error, unexpected expression, "
+                                                       "expecting %s"), MODE_TO_STRING(parser_mode));
+                               sdb_object_deref(SDB_OBJ($1));
+                               YYABORT;
+                       }
+
+                       if ($1) {
+                               sdb_conn_node_t *n;
+                               n = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
+                                                       conn_expr_t, conn_expr_destroy));
+                               n->cmd = CONNECTION_EXPR;
+                               CONN_EXPR(n)->expr = $1;
+
+                               sdb_llist_append(pt, SDB_OBJ(n));
+                               sdb_object_deref(SDB_OBJ(n));
+                       }
+               }
        ;
 
 statement:
@@ -219,27 +278,26 @@ statement:
  * Retrieve detailed information about a single host.
  */
 fetch_statement:
-       FETCH IDENTIFIER STRING filter_clause
+       FETCH object_type STRING filter_clause
                {
-                       /* TODO: support other types as well */
-                       if (strcasecmp($2, "host")) {
-                               char errmsg[strlen($2) + 32];
-                               snprintf(errmsg, sizeof(errmsg),
-                                               YY_("unknown data-source %s"), $2);
-                               sdb_fe_yyerror(&yylloc, scanner, errmsg);
-                               free($2); $2 = NULL;
-                               free($3); $3 = NULL;
-                               sdb_object_deref(SDB_OBJ($4));
-                               YYABORT;
-                       }
-
                        $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
                                                conn_fetch_t, conn_fetch_destroy));
-                       CONN_FETCH($$)->type = SDB_HOST;
-                       CONN_FETCH($$)->name = $3;
+                       CONN_FETCH($$)->type = $2;
+                       CONN_FETCH($$)->host = $3;
+                       CONN_FETCH($$)->name = NULL;
                        CONN_FETCH($$)->filter = CONN_MATCHER($4);
                        $$->cmd = CONNECTION_FETCH;
-                       free($2); $2 = NULL;
+               }
+       |
+       FETCH object_type STRING '.' STRING filter_clause
+               {
+                       $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
+                                               conn_fetch_t, conn_fetch_destroy));
+                       CONN_FETCH($$)->type = $2;
+                       CONN_FETCH($$)->host = $3;
+                       CONN_FETCH($$)->name = $5;
+                       CONN_FETCH($$)->filter = CONN_MATCHER($6);
+                       $$->cmd = CONNECTION_FETCH;
                }
        ;
 
@@ -249,25 +307,13 @@ fetch_statement:
  * Returns a list of all hosts in the store.
  */
 list_statement:
-       LIST IDENTIFIER filter_clause
-               {
-                       int type = sdb_store_parse_object_type_plural($2);
-                       if (type < 0) {
-                               char errmsg[strlen($2) + 32];
-                               snprintf(errmsg, sizeof(errmsg),
-                                               YY_("unknown data-source %s"), $2);
-                               sdb_fe_yyerror(&yylloc, scanner, errmsg);
-                               free($2); $2 = NULL;
-                               sdb_object_deref(SDB_OBJ($3));
-                               YYABORT;
-                       }
-
+       LIST object_type_plural filter_clause
+               {
                        $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
                                                conn_list_t, conn_list_destroy));
-                       CONN_LIST($$)->type = type;
+                       CONN_LIST($$)->type = $2;
                        CONN_LIST($$)->filter = CONN_MATCHER($3);
                        $$->cmd = CONNECTION_LIST;
-                       free($2); $2 = NULL;
                }
        ;
 
@@ -277,19 +323,9 @@ list_statement:
  * Returns detailed information about <type> matching condition.
  */
 lookup_statement:
-       LOOKUP IDENTIFIER matching_clause filter_clause
+       LOOKUP HOSTS_T matching_clause filter_clause
                {
                        /* TODO: support other types as well */
-                       if (strcasecmp($2, "hosts")) {
-                               char errmsg[strlen($2) + 32];
-                               snprintf(errmsg, sizeof(errmsg),
-                                               YY_("unknown data-source %s"), $2);
-                               sdb_fe_yyerror(&yylloc, scanner, errmsg);
-                               free($2); $2 = NULL;
-                               sdb_object_deref(SDB_OBJ($3));
-                               sdb_object_deref(SDB_OBJ($4));
-                               YYABORT;
-                       }
 
                        $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
                                                conn_lookup_t, conn_lookup_destroy));
@@ -297,7 +333,6 @@ lookup_statement:
                        CONN_LOOKUP($$)->matcher = CONN_MATCHER($3);
                        CONN_LOOKUP($$)->filter = CONN_MATCHER($4);
                        $$->cmd = CONNECTION_LOOKUP;
-                       free($2); $2 = NULL;
                }
        ;
 
@@ -355,7 +390,7 @@ condition:
 
                        $$ = SDB_CONN_NODE(sdb_object_create_dT(/* name = */ NULL,
                                                conn_matcher_t, conn_matcher_destroy));
-                       $$->cmd = CONNECTION_EXPR;
+                       $$->cmd = CONNECTION_MATCHER;
                        CONN_MATCHER($$)->matcher = $1;
                }
        ;
@@ -392,51 +427,45 @@ matcher:
                }
        ;
 
-/*
- * <object_type>.<object_attr> <op> <value>
- *
- * Parse matchers comparing object attributes with a value.
- */
 compare_matcher:
-       ':' IDENTIFIER op expression
+       expression cmp expression
                {
-                       $$ = sdb_store_matcher_parse_field_cmp($2, $3, $4);
-                       free($2); $2 = NULL;
+                       sdb_store_matcher_op_cb cb = sdb_store_parse_matcher_op($2);
+                       assert(cb); /* else, the grammar accepts invalid 'cmp' */
+                       $$ = cb($1, $3);
+                       sdb_object_deref(SDB_OBJ($1));
+                       sdb_object_deref(SDB_OBJ($3));
+               }
+       |
+       ANY iterable cmp expression
+               {
+                       $$ = name_iter_matcher(MATCHER_ANY, $2, $3, $4);
                        sdb_object_deref(SDB_OBJ($4));
                }
        |
-       IDENTIFIER op expression
+       ALL iterable cmp expression
                {
-                       $$ = sdb_store_matcher_parse_cmp($1, NULL, $2, $3);
-                       free($1); $1 = NULL;
-                       sdb_object_deref(SDB_OBJ($3));
+                       $$ = name_iter_matcher(MATCHER_ALL, $2, $3, $4);
+                       sdb_object_deref(SDB_OBJ($4));
                }
        |
-       IDENTIFIER '[' IDENTIFIER ']' op expression
+       expression IS NULL_T
                {
-                       $$ = sdb_store_matcher_parse_cmp($1, $3, $5, $6);
-                       free($1); $1 = NULL;
-                       free($3); $3 = NULL;
-                       sdb_object_deref(SDB_OBJ($6));
+                       $$ = sdb_store_isnull_matcher($1);
+                       sdb_object_deref(SDB_OBJ($1));
                }
        |
-       IDENTIFIER '[' IDENTIFIER ']' IS NULL_T
+       expression IS NOT NULL_T
                {
-                       $$ = sdb_store_matcher_parse_cmp($1, $3, "IS", NULL);
-                       free($1); $1 = NULL;
-                       free($3); $3 = NULL;
+                       $$ = sdb_store_isnnull_matcher($1);
+                       sdb_object_deref(SDB_OBJ($1));
                }
        |
-       IDENTIFIER '[' IDENTIFIER ']' IS NOT NULL_T
+       expression IN expression
                {
-                       sdb_store_matcher_t *m;
-                       m = sdb_store_matcher_parse_cmp($1, $3, "IS", NULL);
-                       free($1); $1 = NULL;
-                       free($3); $3 = NULL;
-
-                       /* sdb_store_inv_matcher return NULL if m==NULL */
-                       $$ = sdb_store_inv_matcher(m);
-                       sdb_object_deref(SDB_OBJ(m));
+                       $$ = sdb_store_in_matcher($1, $3);
+                       sdb_object_deref(SDB_OBJ($1));
+                       sdb_object_deref(SDB_OBJ($3));
                }
        ;
 
@@ -481,11 +510,29 @@ expression:
                        sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
                }
        |
-       ':' IDENTIFIER
+       expression CONCAT expression
                {
-                       int field = sdb_store_parse_field_name($2);
-                       free($2); $2 = NULL;
-                       $$ = sdb_store_expr_fieldvalue(field);
+                       $$ = sdb_store_expr_create(SDB_DATA_CONCAT, $1, $3);
+                       sdb_object_deref(SDB_OBJ($1)); $1 = NULL;
+                       sdb_object_deref(SDB_OBJ($3)); $3 = NULL;
+               }
+       |
+       HOST_T
+               {
+                       /* TODO: this only works as long as queries
+                        * are limited to hosts */
+                       $$ = sdb_store_expr_fieldvalue(SDB_FIELD_NAME);
+               }
+       |
+       field
+               {
+                       $$ = sdb_store_expr_fieldvalue($1);
+               }
+       |
+       ATTRIBUTE_T '[' STRING ']'
+               {
+                       $$ = sdb_store_expr_attrvalue($3);
+                       free($3); $3 = NULL;
                }
        |
        data
@@ -495,7 +542,43 @@ expression:
                }
        ;
 
-op:
+object_type:
+       HOST_T { $$ = SDB_HOST; }
+       |
+       SERVICE_T { $$ = SDB_SERVICE; }
+       |
+       METRIC_T { $$ = SDB_METRIC; }
+       ;
+
+object_type_plural:
+       HOSTS_T { $$ = SDB_HOST; }
+       |
+       SERVICES_T { $$ = SDB_SERVICE; }
+       |
+       METRICS_T { $$ = SDB_METRIC; }
+       ;
+
+iterable:
+       SERVICE_T { $$ = SDB_SERVICE; }
+       |
+       METRIC_T { $$ = SDB_METRIC; }
+       |
+       ATTRIBUTE_T { $$ = SDB_ATTRIBUTE; }
+       ;
+
+field:
+       NAME_T { $$ = SDB_FIELD_NAME; }
+       |
+       LAST_UPDATE_T { $$ = SDB_FIELD_LAST_UPDATE; }
+       |
+       AGE_T { $$ = SDB_FIELD_AGE; }
+       |
+       INTERVAL_T { $$ = SDB_FIELD_INTERVAL; }
+       |
+       BACKEND_T { $$ = SDB_FIELD_BACKEND; }
+       ;
+
+cmp:
        CMP_EQUAL { $$ = "="; }
        |
        CMP_NEQUAL { $$ = "!="; }
@@ -549,10 +632,8 @@ interval_elem:
 
                        unit = sdb_strpunit($2);
                        if (! unit) {
-                               char errmsg[strlen($2) + 32];
-                               snprintf(errmsg, sizeof(errmsg),
+                               sdb_fe_yyerrorf(&yylloc, scanner,
                                                YY_("invalid time unit %s"), $2);
-                               sdb_fe_yyerror(&yylloc, scanner, errmsg);
                                free($2); $2 = NULL;
                                YYABORT;
                        }
@@ -575,7 +656,45 @@ void
 sdb_fe_yyerror(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *msg)
 {
        sdb_log(SDB_LOG_ERR, "frontend: parse error: %s", msg);
+       sdb_strbuf_sprintf(errbuf, "%s", msg);
 } /* sdb_fe_yyerror */
 
+void
+sdb_fe_yyerrorf(YYLTYPE *lval, sdb_fe_yyscan_t scanner, const char *fmt, ...)
+{
+       va_list ap, aq;
+       va_start(ap, fmt);
+       va_copy(aq, ap);
+       sdb_vlog(SDB_LOG_ERR, fmt, ap);
+       sdb_strbuf_vsprintf(errbuf, "%s", aq);
+       va_end(ap);
+} /* sdb_fe_yyerrorf */
+
+static sdb_store_matcher_t *
+name_iter_matcher(int m_type, int type, const char *cmp,
+               sdb_store_expr_t *expr)
+{
+       sdb_store_matcher_op_cb cb = sdb_store_parse_matcher_op(cmp);
+       sdb_store_expr_t *e;
+       sdb_store_matcher_t *m, *tmp = NULL;
+       assert(cb);
+
+       /* TODO: this only works as long as queries
+        * are limited to hosts */
+       if (type == SDB_HOST) {
+               return NULL;
+       }
+
+       e = sdb_store_expr_fieldvalue(SDB_FIELD_NAME);
+       m = cb(e, expr);
+       if (m_type == MATCHER_ANY)
+               tmp = sdb_store_any_matcher(type, m);
+       else if (m_type == MATCHER_ALL)
+               tmp = sdb_store_all_matcher(type, m);
+       sdb_object_deref(SDB_OBJ(m));
+       sdb_object_deref(SDB_OBJ(e));
+       return tmp;
+} /* name_iter_matcher */
+
 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */