X-Git-Url: http://git.liburcu.org/?a=blobdiff_plain;f=liblttng-ust%2Flttng-filter.h;h=23ccff2318def4a882ee05fc6738a582e5949f0d;hb=b9389e6efa5e337e3de81062070f2e0dff1a4222;hp=4ef1c757635eaf5edae394df19511c932b5682b0;hpb=97b58163ffe6cced54c3d37ae79d4113a9d26455;p=lttng-ust.git

diff --git a/liblttng-ust/lttng-filter.h b/liblttng-ust/lttng-filter.h
index 4ef1c757..23ccff23 100644
--- a/liblttng-ust/lttng-filter.h
+++ b/liblttng-ust/lttng-filter.h
@@ -27,7 +27,9 @@
 #include <stdio.h>
 #include <helper.h>
 #include <lttng/ust-events.h>
+#include <lttng/ust-context-provider.h>
 #include <stdint.h>
+#include <assert.h>
 #include <errno.h>
 #include <string.h>
 #include <inttypes.h>
@@ -35,7 +37,9 @@
 #include <usterr-signal-safe.h>
 #include "filter-bytecode.h"
 
-#define NR_REG		2
+/* Filter stack length, in number of entries */
+#define FILTER_STACK_LEN	10	/* includes 2 dummy */
+#define FILTER_STACK_EMPTY	1
 
 #ifndef min_t
 #define min_t(type, a, b)	\
@@ -51,54 +55,162 @@
 #endif
 
 #ifdef DEBUG
-#define dbg_printf(fmt, args...)     printf("[debug bytecode] " fmt, ## args)
+#define dbg_printf(fmt, args...)				\
+	printf("[debug bytecode in %s:%s@%u] " fmt,		\
+		__FILE__, __func__, __LINE__, ## args)
 #else
 #define dbg_printf(fmt, args...)				\
 do {								\
 	/* do nothing but check printf format */		\
 	if (0)							\
-		printf("[debug bytecode] " fmt, ## args);	\
+		printf("[debug bytecode in %s:%s@%u] " fmt,	\
+			__FILE__, __func__, __LINE__, ## args);	\
 } while (0)
 #endif
 
-/* Linked bytecode */
+/* Linked bytecode. Child of struct lttng_bytecode_runtime. */
 struct bytecode_runtime {
+	struct lttng_bytecode_runtime p;
 	uint16_t len;
 	char data[0];
 };
 
-enum reg_type {
+enum entry_type {
 	REG_S64,
 	REG_DOUBLE,
 	REG_STRING,
-	REG_TYPE_UNKNOWN,
+	REG_UNKNOWN,
+};
+
+/* Validation stack */
+struct vstack_entry {
+	enum entry_type type;
 };
 
-/* Validation registers */
-struct vreg {
-	enum reg_type type;
-	int literal;		/* is string literal ? */
+struct vstack {
+	int top;	/* top of stack */
+	struct vstack_entry e[FILTER_STACK_LEN];
 };
 
-/* Execution registers */
-struct reg {
-	enum reg_type type;
-	int64_t v;
-	double d;
+static inline
+void vstack_init(struct vstack *stack)
+{
+	stack->top = -1;
+}
+
+static inline
+struct vstack_entry *vstack_ax(struct vstack *stack)
+{
+	if (unlikely(stack->top < 0))
+		return NULL;
+	return &stack->e[stack->top];
+}
+
+static inline
+struct vstack_entry *vstack_bx(struct vstack *stack)
+{
+	if (unlikely(stack->top < 1))
+		return NULL;
+	return &stack->e[stack->top - 1];
+}
+
+static inline
+int vstack_push(struct vstack *stack)
+{
+	if (stack->top >= FILTER_STACK_LEN - 1) {
+		ERR("Stack full\n");
+		return -EINVAL;
+	}
+	++stack->top;
+	return 0;
+}
+
+static inline
+int vstack_pop(struct vstack *stack)
+{
+	if (unlikely(stack->top < 0)) {
+		ERR("Stack empty\n");
+		return -EINVAL;
+	}
+	stack->top--;
+	return 0;
+}
+
+/* Execution stack */
+struct estack_entry {
+	enum entry_type type;	/* For dynamic typing. */
+	union {
+		int64_t v;
+		double d;
+
+		struct {
+			const char *str;
+			size_t seq_len;
+			int literal;		/* is string literal ? */
+		} s;
+	} u;
+};
 
-	const char *str;
-	size_t seq_len;
-	int literal;		/* is string literal ? */
+struct estack {
+	int top;	/* top of stack */
+	struct estack_entry e[FILTER_STACK_LEN];
 };
 
+/*
+ * Always use aliased type for ax/bx (top of stack).
+ * When ax/bx are S64, use aliased value.
+ */
+#define estack_ax_v	ax
+#define estack_bx_v	bx
+#define estack_ax_t	ax_t
+#define estack_bx_t	bx_t
+
+/*
+ * ax and bx registers can hold either integer, double or string.
+ */
+#define estack_ax(stack, top)					\
+	({							\
+		assert((top) > FILTER_STACK_EMPTY);		\
+		&(stack)->e[top];				\
+	})
+
+#define estack_bx(stack, top)					\
+	({							\
+		assert((top) > FILTER_STACK_EMPTY + 1);		\
+		&(stack)->e[(top) - 1];				\
+	})
+
+/*
+ * Currently, only integers (REG_S64) can be pushed into the stack.
+ */
+#define estack_push(stack, top, ax, bx, ax_t, bx_t)		\
+	do {							\
+		assert((top) < FILTER_STACK_LEN - 1);		\
+		(stack)->e[(top) - 1].u.v = (bx);		\
+		(stack)->e[(top) - 1].type = (bx_t);		\
+		(bx) = (ax);					\
+		(bx_t) = (ax_t);				\
+		++(top);					\
+	} while (0)
+
+#define estack_pop(stack, top, ax, bx, ax_t, bx_t)		\
+	do {							\
+		assert((top) > FILTER_STACK_EMPTY);		\
+		(ax) = (bx);					\
+		(ax_t) = (bx_t);				\
+		(bx) = (stack)->e[(top) - 2].u.v;		\
+		(bx_t) = (stack)->e[(top) - 2].type;		\
+		(top)--;					\
+	} while (0)
+
 const char *print_op(enum filter_op op);
 
 int lttng_filter_validate_bytecode(struct bytecode_runtime *bytecode);
 int lttng_filter_specialize_bytecode(struct bytecode_runtime *bytecode);
 
-int lttng_filter_false(void *filter_data,
+uint64_t lttng_filter_false(void *filter_data,
 		const char *filter_stack_data);
-int lttng_filter_interpret_bytecode(void *filter_data,
+uint64_t lttng_filter_interpret_bytecode(void *filter_data,
 		const char *filter_stack_data);
 
 #endif /* _LTTNG_FILTER_H */