ust registry: Refactor representation of nested types

[lttng-tools.git] / src / bin / lttng-sessiond / ust-ctl-internal.h

diff --git a/src/bin/lttng-sessiond/ust-ctl-internal.h b/src/bin/lttng-sessiond/ust-ctl-internal.h
index 96099f8aa08926aee758293f6ccc3e30652780f9..7c245bdce266489e54b8258c4de06fbc343ae0a6 100644 (file)
--- a/src/bin/lttng-sessiond/ust-ctl-internal.h
+++ b/src/bin/lttng-sessiond/ust-ctl-internal.h
@@ -279,13 +279,18 @@ 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,
 };
 
@@ -339,6 +344,7 @@ struct ustctl_enum_entry {
        } u;
 } LTTNG_PACKED;
 
+/* legacy */
 #define USTCTL_UST_BASIC_TYPE_PADDING  296
 union _ustctl_basic_type {
        struct ustctl_integer_type integer;
@@ -354,6 +360,7 @@ union _ustctl_basic_type {
        char padding[USTCTL_UST_BASIC_TYPE_PADDING];
 } LTTNG_PACKED;
 
+/* legacy */
 struct ustctl_basic_type {
        enum ustctl_abstract_types atype;
        union {
@@ -361,28 +368,67 @@ 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;