tracepoint: Refactor representation of nested types

[lttng-ust.git] / include / lttng / ust-ctl.h

diff --git a/include/lttng/ust-ctl.h b/include/lttng/ust-ctl.h
index 57758edb19d15efe5032a5eebf4e4d3e1c1367b4..19fba726b56c049a141b5259b2105d1f76d6fadb 100644 (file)
--- a/include/lttng/ust-ctl.h
+++ b/include/lttng/ust-ctl.h
@@ -19,9 +19,12 @@
 #ifndef _LTTNG_UST_CTL_H
 #define _LTTNG_UST_CTL_H
 
-#include <lttng/ust-abi.h>
-#include <sys/types.h>
 #include <limits.h>
+#include <stddef.h>
+#include <stdint.h>
+#include <sys/types.h>
+
+#include <lttng/ust-abi.h>
 
 #ifndef LTTNG_PACKED
 #error "LTTNG_PACKED should be defined"
@@ -242,8 +245,15 @@ int ustctl_put_subbuf(struct ustctl_consumer_stream *stream);
 
 void ustctl_flush_buffer(struct ustctl_consumer_stream *stream,
                int producer_active);
+void ustctl_clear_buffer(struct ustctl_consumer_stream *stream);
 
 /* index */
+
+/*
+ * Getters which need to be used on the current packet (between get/put
+ * or get_next/put_next.
+ */
+
 int ustctl_get_timestamp_begin(struct ustctl_consumer_stream *stream,
                uint64_t *timestamp_begin);
 int ustctl_get_timestamp_end(struct ustctl_consumer_stream *stream,
@@ -254,15 +264,26 @@ int ustctl_get_content_size(struct ustctl_consumer_stream *stream,
        uint64_t *content_size);
 int ustctl_get_packet_size(struct ustctl_consumer_stream *stream,
        uint64_t *packet_size);
-int ustctl_get_stream_id(struct ustctl_consumer_stream *stream,
-               uint64_t *stream_id);
-int ustctl_get_current_timestamp(struct ustctl_consumer_stream *stream,
-               uint64_t *ts);
 int ustctl_get_sequence_number(struct ustctl_consumer_stream *stream,
                uint64_t *seq);
+
+/*
+ * Getter returning state invariant for the stream, which can be used
+ * without "get" operation.
+ */
+
+int ustctl_get_stream_id(struct ustctl_consumer_stream *stream,
+               uint64_t *stream_id);
 int ustctl_get_instance_id(struct ustctl_consumer_stream *stream,
                uint64_t *id);
 
+/*
+ * Getter returning the current timestamp as perceived from the
+ * tracer.
+ */
+int ustctl_get_current_timestamp(struct ustctl_consumer_stream *stream,
+               uint64_t *ts);
+
 /* returns whether UST has perf counters support. */
 int ustctl_has_perf_counters(void);
 
@@ -292,13 +313,18 @@ enum ustctl_channel_header {
 
 enum ustctl_abstract_types {
        ustctl_atype_integer,
-       ustctl_atype_enum,
-       ustctl_atype_array,
-       ustctl_atype_sequence,
+       ustctl_atype_enum,      /* legacy */
+       ustctl_atype_array,     /* legacy */
+       ustctl_atype_sequence,  /* legacy */
        ustctl_atype_string,
        ustctl_atype_float,
-       ustctl_atype_variant,
-       ustctl_atype_struct,
+       ustctl_atype_variant,   /* legacy */
+       ustctl_atype_struct,    /* legacy */
+       ustctl_atype_enum_nestable,
+       ustctl_atype_array_nestable,
+       ustctl_atype_sequence_nestable,
+       ustctl_atype_struct_nestable,
+       ustctl_atype_variant_nestable,
        NR_USTCTL_ABSTRACT_TYPES,
 };
 
@@ -352,6 +378,7 @@ struct ustctl_enum_entry {
        } u;
 } LTTNG_PACKED;
 
+/* legacy */
 #define USTCTL_UST_BASIC_TYPE_PADDING  296
 union _ustctl_basic_type {
        struct ustctl_integer_type integer;
@@ -367,6 +394,7 @@ union _ustctl_basic_type {
        char padding[USTCTL_UST_BASIC_TYPE_PADDING];
 } LTTNG_PACKED;
 
+/* legacy */
 struct ustctl_basic_type {
        enum ustctl_abstract_types atype;
        union {
@@ -374,28 +402,67 @@ struct ustctl_basic_type {
        } u;
 } LTTNG_PACKED;
 
-#define USTCTL_UST_TYPE_PADDING        128
+/*
+ * Padding is derived from largest member: u.legacy.sequence which
+ * contains two basic types, each with USTCTL_UST_BASIC_TYPE_PADDING.
+ */
+#define USTCTL_UST_TYPE_PADDING        (2 * USTCTL_UST_BASIC_TYPE_PADDING)
 struct ustctl_type {
        enum ustctl_abstract_types atype;
        union {
-               union _ustctl_basic_type basic;
+               struct ustctl_integer_type integer;
+               struct ustctl_float_type _float;
+               struct {
+                       int32_t encoding;       /* enum ustctl_string_encodings */
+               } string;
+               struct {
+                       char name[LTTNG_UST_SYM_NAME_LEN];
+                       uint64_t id;    /* enum ID in sessiond. */
+                       /* container_type follows after this struct ustctl_field. */
+               } enum_nestable;
                struct {
-                       struct ustctl_basic_type elem_type;
                        uint32_t length;                /* num. elems. */
-               } array;
+                       uint32_t alignment;
+                       /* elem_type follows after this struct ustctl_field. */
+               } array_nestable;
                struct {
-                       struct ustctl_basic_type length_type;
-                       struct ustctl_basic_type elem_type;
-               } sequence;
+                       char length_name[LTTNG_UST_SYM_NAME_LEN];
+                       uint32_t alignment;             /* Alignment before elements. */
+                       /* elem_type follows after the length_type. */
+               } sequence_nestable;
+               struct {
+                       uint32_t nr_fields;
+                       uint32_t alignment;
+                       /* Followed by nr_fields struct ustctl_field. */
+               } struct_nestable;
                struct {
                        uint32_t nr_choices;
                        char tag_name[LTTNG_UST_SYM_NAME_LEN];
+                       uint32_t alignment;
                        /* Followed by nr_choices struct ustctl_field. */
-               } variant;
-               struct {
-                       uint32_t nr_fields;
-                       /* Followed by nr_fields struct ustctl_field. */
-               } _struct;
+               } variant_nestable;
+
+               /* Legacy ABI */
+               union {
+                       union _ustctl_basic_type basic;
+                       struct {
+                               struct ustctl_basic_type elem_type;
+                               uint32_t length;                /* num. elems. */
+                       } array;
+                       struct {
+                               struct ustctl_basic_type length_type;
+                               struct ustctl_basic_type elem_type;
+                       } sequence;
+                       struct {
+                               uint32_t nr_fields;
+                               /* Followed by nr_fields struct ustctl_field. */
+                       } _struct;
+                       struct {
+                               uint32_t nr_choices;
+                               char tag_name[LTTNG_UST_SYM_NAME_LEN];
+                               /* Followed by nr_choices struct ustctl_field. */
+                       } variant;
+               } legacy;
                char padding[USTCTL_UST_TYPE_PADDING];
        } u;
 } LTTNG_PACKED;