infix notation parser almost done; preparing the evaluator and variables lookup

3 files changed, 168 insertions, 8 deletions

diff --git a/profile/benchmark-dictionary.c b/profile/benchmark-dictionary.c
index 846e3c61ac..8ec3ae0318 100644
--- a/profile/benchmark-dictionary.c
+++ b/profile/benchmark-dictionary.c
@@ -7,13 +7,6 @@
  *
  */
 
-#include <stdio.h>
-#include <stdlib.h>
-#include <inttypes.h>
-
-#include "dictionary.h"
-#include "main.h"
-#include "log.h"
 #include "common.h"
 
 struct myvalue {
diff --git a/profile/benchmark-registry.c b/profile/benchmark-registry.c
index 68475eae09..fd771a7a78 100755
--- a/profile/benchmark-registry.c
+++ b/profile/benchmark-registry.c
@@ -1,13 +1,15 @@
 
 /*
  * compile with
- *  gcc -O1 -ggdb -Wall -Wextra -I ../src/ -I ../ -o benchmark-registry benchmark-registry.c ../src/dictionary.o ../src/log.o ../src/avl.o ../src/common.o ../src/appconfig.o ../src/web_buffer.o ../src/storage_number.o ../src/rrd.o -pthread -luuid -lm -DHAVE_CONFIG_H -DVARLIB_DIR="\"/tmp\""
+ *  gcc -O1 -ggdb -Wall -Wextra -I ../src/ -I ../ -o benchmark-registry benchmark-registry.c ../src/dictionary.o ../src/log.o ../src/avl.o ../src/common.o ../src/appconfig.o ../src/web_buffer.o ../src/storage_number.o ../src/rrd.o ../src/health.o -pthread -luuid -lm -DHAVE_CONFIG_H -DVARLIB_DIR="\"/tmp\""
  */
 
 char *hostname = "me";
 
 #include "../src/registry.c"
 
+void netdata_cleanup_and_exit(int ret) { exit(ret); }
+
 // ----------------------------------------------------------------------------
 // TESTS
 
diff --git a/profile/test-eval.c b/profile/test-eval.c
new file mode 100644
index 0000000000..509eab5662
--- /dev/null
+++ b/profile/test-eval.c
@@ -0,0 +1,165 @@
+
+/*
+ * 1. build netdata (as normally)
+ * 2. cd profile/
+ * 3. compile with:
+ *    gcc -O1 -ggdb -Wall -Wextra -I ../src/ -I ../ -o test-eval test-eval.c ../src/log.o ../src/eval.o ../src/common.o -pthread
+ *
+ */
+
+#include "common.h"
+
+void netdata_cleanup_and_exit(int ret) { exit(ret); }
+
+void indent(int level, int show) {
+	int i = level;
+	while(i--) printf(" |  ");
+	if(show) printf(" \\_ ");
+	else printf(" \\_  ");
+}
+
+void print_operand(EVAL_OPERAND *op, int level);
+
+void print_value(EVAL_VALUE *v, int level) {
+	indent(level, 0);
+
+	switch(v->type) {
+		case EVAL_VALUE_INVALID:
+			printf("VALUE (NOP)\n");
+			break;
+
+		case EVAL_VALUE_NUMBER:
+			printf("VALUE %Lf (NUMBER)\n", v->number);
+			break;
+
+		case EVAL_VALUE_EXPRESSION:
+			printf("VALUE (SUB-EXPRESSION)\n");
+			print_operand(v->expression, level+1);
+			break;
+
+		default:
+			printf("VALUE (INVALID type %d)\n", v->type);
+			break;
+
+	}
+}
+
+void print_operand(EVAL_OPERAND *op, int level) {
+
+//	if(op->operator != EVAL_OPERATOR_NOP) {
+		indent(level, 1);
+		if(op->operator) printf("%c (OPERATOR %d, prec: %d)\n", op->operator, op->id, op->precedence);
+		else printf("NOP (OPERATOR %d, prec: %d)\n", op->id, op->precedence);
+//	}
+
+	int i = op->count;
+	while(i--) print_value(&op->ops[i], level + 1);
+}
+
+calculated_number evaluate(EVAL_OPERAND *op);
+
+calculated_number evaluate_value(EVAL_VALUE *v) {
+	switch(v->type) {
+		case EVAL_VALUE_NUMBER:
+			return v->number;
+
+		case EVAL_VALUE_EXPRESSION:
+			return evaluate(v->expression);
+
+		default:
+			fatal("I don't know how to handle EVAL_VALUE type %d", v->type);
+	}
+}
+
+calculated_number evaluate(EVAL_OPERAND *op) {
+	calculated_number n1, n2, r;
+
+	switch(op->operator) {
+		case EVAL_OPERATOR_SIGN_PLUS:
+			r = evaluate_value(&op->ops[0]);
+			break;
+
+		case EVAL_OPERATOR_SIGN_MINUS:
+			r = -evaluate_value(&op->ops[0]);
+			break;
+
+		case EVAL_OPERATOR_PLUS:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0]);
+			n2 = evaluate_value(&op->ops[1]);
+			r = n1 + n2;
+			printf("%Lf = %Lf %c %Lf\n", r, n1, op->operator, n2);
+			break;
+
+		case EVAL_OPERATOR_MINUS:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0]);
+			n2 = evaluate_value(&op->ops[1]);
+			r = n1 - n2;
+			printf("%Lf = %Lf %c %Lf\n", r, n1, op->operator, n2);
+			break;
+
+		case EVAL_OPERATOR_MULTIPLY:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0]);
+			n2 = evaluate_value(&op->ops[1]);
+			r = n1 * n2;
+			printf("%Lf = %Lf %c %Lf\n", r, n1, op->operator, n2);
+			break;
+
+		case EVAL_OPERATOR_DIVIDE:
+			if(op->count != 2)
+				fatal("Operator '%c' requires 2 values, but we have %d", op->operator, op->count);
+			n1 = evaluate_value(&op->ops[0]);
+			n2 = evaluate_value(&op->ops[1]);
+			r = n1 / n2;
+			printf("%Lf = %Lf %c %Lf\n", r, n1, op->operator, n2);
+			break;
+
+		case EVAL_OPERATOR_EXPRESSION_OPEN:
+			printf("BEGIN SUB-EXPRESSION\n");
+			r = evaluate_value(&op->ops[0]);
+			printf("END SUB-EXPRESSION\n");
+			break;
+
+		case EVAL_OPERATOR_NOP:
+		case EVAL_OPERATOR_VALUE:
+			r = evaluate_value(&op->ops[0]);
+			break;
+
+		default:
+			fatal("I don't know how to handle operator '%c'", op->operator);
+			break;
+	}
+
+	return r;
+}
+
+void print_expression(EVAL_OPERAND *op, const char *failed_at, int error) {
+	if(op) {
+		printf("<expression root>\n");
+		print_operand(op, 0);
+		evaluate(op);
+		free_expression(op);
+	}
+	else {
+		printf("error: %d, failed_at: '%s'\n", error, (failed_at)?failed_at:"<NONE>");
+	}
+}
+
+
+int main(int argc, char **argv) {
+	if(argc != 2) {
+		fprintf(stderr, "I need an epxression\n");
+		exit(1);
+	}
+
+	const char *failed_at = NULL;
+	int error;
+	EVAL_OPERAND *op = parse_expression(argv[1], &failed_at, &error);
+	print_expression(op, failed_at, error);
+	return 0;
+}