Implement support for brackets in filter expressions

[lttng-tools.git] / src / lib / lttng-ctl / filter / filter-visitor-generate-ir.c

diff --git a/src/lib/lttng-ctl/filter/filter-visitor-generate-ir.c b/src/lib/lttng-ctl/filter/filter-visitor-generate-ir.c
index e3dc1aab9481467ec4140341255b099b4d71ff76..85aadcae6fe7baedec1b30d8d34960c65c5b43fd 100644 (file)
--- a/src/lib/lttng-ctl/filter/filter-visitor-generate-ir.c
+++ b/src/lib/lttng-ctl/filter/filter-visitor-generate-ir.c
@@ -140,7 +140,8 @@ struct ir_op *make_op_load_float(double v, enum ir_side side)
 }
 
 static
-struct ir_op *make_op_load_field_ref(char *string, enum ir_side side)
+struct ir_op *make_op_load_field_ref(char *string,
+               enum ir_side side)
 {
        struct ir_op *op;
 
@@ -153,14 +154,61 @@ struct ir_op *make_op_load_field_ref(char *string, enum ir_side side)
        op->side = side;
        op->u.load.u.ref = strdup(string);
        if (!op->u.load.u.ref) {
-               free(op);
+               goto error;
+       }
+       return op;
+
+error:
+       free(op);
+       return NULL;
+}
+
+static
+struct ir_op *make_op_load_field_ref_index(char *string,
+               struct filter_node *next,
+               enum ir_side side)
+{
+       struct ir_op *op;
+
+       op = calloc(sizeof(struct ir_op), 1);
+       if (!op)
                return NULL;
+       op->op = IR_OP_LOAD;
+       op->data_type = IR_DATA_FIELD_REF_INDEX;
+       op->signedness = IR_SIGN_DYN;
+       op->side = side;
+       op->u.load.u.ref_index.symbol = strdup(string);
+       if (!op->u.load.u.ref_index.symbol) {
+               goto error;
+       }
+       /* Only positive integer literals accepted as index. */
+       if (next->type == NODE_UNARY_OP) {
+               fprintf(stderr, "[error] Unexpected unary operator as index\n");
+               goto error;
+       }
+       if (next->type != NODE_EXPRESSION) {
+               fprintf(stderr, "[error] Expecting expression as index\n");
+               goto error;
+       }
+       if (next->u.expression.type != AST_EXP_CONSTANT) {
+               fprintf(stderr, "[error] Expecting constant index\n");
+               goto error;
+       }
+       if (next->u.expression.u.constant < 0) {
+               fprintf(stderr, "[error] Expecting positive constant index\n");
+               goto error;
        }
+       op->u.load.u.ref_index.index = next->u.expression.u.constant;
        return op;
+
+error:
+       free(op);
+       return NULL;
 }
 
 static
-struct ir_op *make_op_load_get_context_ref(char *string, enum ir_side side)
+struct ir_op *make_op_load_get_context_ref(char *string,
+               enum ir_side side)
 {
        struct ir_op *op;
 
@@ -173,10 +221,56 @@ struct ir_op *make_op_load_get_context_ref(char *string, enum ir_side side)
        op->side = side;
        op->u.load.u.ref = strdup(string);
        if (!op->u.load.u.ref) {
-               free(op);
+               goto error;
+       }
+       return op;
+
+error:
+       free(op);
+       return NULL;
+}
+
+static
+struct ir_op *make_op_load_get_context_ref_index(char *string,
+               struct filter_node *next,
+               enum ir_side side)
+{
+       struct ir_op *op;
+
+       op = calloc(sizeof(struct ir_op), 1);
+       if (!op)
                return NULL;
+       op->op = IR_OP_LOAD;
+       op->data_type = IR_DATA_GET_CONTEXT_REF_INDEX;
+       op->signedness = IR_SIGN_DYN;
+       op->side = side;
+       op->u.load.u.ref_index.symbol = strdup(string);
+       if (!op->u.load.u.ref_index.symbol) {
+               goto error;
+       }
+       /* Only positive integer literals accepted as offset. */
+       if (next->type == NODE_UNARY_OP) {
+               fprintf(stderr, "[error] Unexpected unary operator as index\n");
+               goto error;
+       }
+       if (next->type != NODE_EXPRESSION) {
+               fprintf(stderr, "[error] Expecting expression as index\n");
+               goto error;
        }
+       if (next->u.expression.type != AST_EXP_CONSTANT) {
+               fprintf(stderr, "[error] Expecting constant index\n");
+               goto error;
+       }
+       if (next->u.expression.u.constant < 0) {
+               fprintf(stderr, "[error] Expecting positive constant index\n");
+               goto error;
+       }
+       op->u.load.u.ref_index.index = next->u.expression.u.constant;
        return op;
+
+error:
+       free(op);
+       return NULL;
 }
 
 static
@@ -390,6 +484,10 @@ void filter_free_ir_recursive(struct ir_op *op)
                case IR_DATA_GET_CONTEXT_REF:
                        free(op->u.load.u.ref);
                        break;
+               case IR_DATA_FIELD_REF_INDEX:   /* fall-through */
+               case IR_DATA_GET_CONTEXT_REF_INDEX:
+                       free(op->u.load.u.ref_index.symbol);
+                       break;
                default:
                        break;
                }
@@ -428,12 +526,18 @@ struct ir_op *make_expression(struct filter_parser_ctx *ctx,
                return make_op_load_float(node->u.expression.u.float_constant,
                                        side);
        case AST_EXP_IDENTIFIER:
-               if (node->u.expression.pre_op != AST_LINK_UNKNOWN) {
+               switch (node->u.expression.pre_op) {
+               case AST_LINK_UNKNOWN:
+                       return make_op_load_field_ref(node->u.expression.u.identifier,
+                                       side);
+               case AST_LINK_BRACKET:
+                       return make_op_load_field_ref_index(node->u.expression.u.identifier,
+                                       node->u.expression.next,
+                                       side);
+               default:
                        fprintf(stderr, "[error] %s: dotted and dereferenced identifiers not supported\n", __func__);
                        return NULL;
                }
-               return make_op_load_field_ref(node->u.expression.u.identifier,
-                                       side);
        case AST_EXP_GLOBAL_IDENTIFIER:
        {
                const char *name;
@@ -459,8 +563,19 @@ struct ir_op *make_expression(struct filter_parser_ctx *ctx,
                        fprintf(stderr, "[error] %s: Expecting a context name, e.g. \'$ctx.name\'.\n", __func__);
                        return NULL;
                }
-               return make_op_load_get_context_ref(node->u.expression.u.identifier,
+               switch (node->u.expression.pre_op) {
+               case AST_LINK_UNKNOWN:
+                       return make_op_load_get_context_ref(node->u.expression.u.identifier,
                                        side);
+               case AST_LINK_BRACKET:
+                       return make_op_load_get_context_ref_index(node->u.expression.u.identifier,
+                                       node->u.expression.next,
+                                       side);
+               default:
+                       fprintf(stderr, "[error] %s: dotted and dereferenced identifiers not supported\n", __func__);
+                       return NULL;
+               }
+
        }
        case AST_EXP_NESTED:
                return generate_ir_recursive(ctx, node->u.expression.u.child,