docs/modules/yaml/pages/static-array-ft-obj.adoc

   1 = YAML static array field type objects
   2
   3 A _**static array field type object**_ is the type of static array data
   4 fields, found in xref:how-barectf-works:ctf-primer.adoc#ds[data
   5 streams].
   6
   7 A static array data field is a sequence of data fields, or
   8 _elements_. In CTF, the number of elements in a static array data field
   9 (its length) is found in the
  10 xref:how-barectf-works:ctf-primer.adoc#trace[metadata stream].
  11
  12 [[props]]
  13 == Properties
  14
  15 [%autowidth.stretch, cols="d,d,a,d"]
  16 |===
  17 |Name |Type |Description |{req-abbr}
  18
  19 |[[class-prop]]`class`
  20 |String
  21 |This property's value must be `static-array`.
  22 |Yes if the <<inherit-prop,`$inherit`>> property is not set.
  23
  24 include::partial$ft-obj-inherit-prop.adoc[]
  25
  26 |[[length-prop]]`length`
  27 |Positive integer
  28 |Number of elements in this field type's instances.
  29 |Yes
  30
  31 |[[element-ft-prop]]`element-field-type`
  32 |xref:ft-obj.adoc[Field type object] (except a
  33 xref:struct-ft-obj.adoc[structure field type object] and a
  34 xref:dyn-array-ft-obj.adoc[dynamic array field type object]) or string
  35 |Type of each element (data fields) in this field type's instances.
  36
  37 If this property's value is a string, it must be the name of an existing
  38 xref:trace-type-obj.adoc#ft-aliases-prop[field type alias]. This
  39 field type must _not_ be a structure field type or a dynamic array
  40 field type.
  41 |Yes
  42 |===
  43
  44 == Generated C{nbsp}types
  45
  46 Pointer to `const __T__`, where `__T__` is the generated C{nbsp}type for
  47 the field type object of the <<element-ft-prop,`element-field-type`
  48 property>>.
  49
  50 .Generated C{nbsp}types for various element field types.
  51 ====
  52 [%autowidth.stretch]
  53 |===
  54 |Element field type |Generated C{nbsp}type
  55
  56 |8-bit unsigned xref:int-ft-obj.adoc[integer]
  57 |`const uint8_t *`
  58
  59 |32-bit signed integer
  60 |`const int32_t *`
  61
  62 |Single-precision xref:real-ft-obj.adoc[real]
  63 |`const float *`
  64
  65 |xref:str-ft-obj.adoc[String]
  66 |`const char * const *`
  67
  68 |Static array of 16-bit signed integers
  69 |`const int16_t * const *`
  70
  71 |Static array of double-precision reals
  72 |`const double * const *`
  73
  74 |Static array of strings
  75 |`const char * const * const *`
  76
  77 |Static array of static arrays of 32-bit unsigned integers
  78 |`const uint32_t * const * const *`
  79 |===
  80 ====
  81
  82 == Examples
  83
  84 .Static array field type object: <<length-prop,four>> 8-bit unsigned xref:int-ft-obj.adoc[integers].
  85 ====
  86 [source,yaml]
  87 ----
  88 class: static-array
  89 length: 4
  90 element-field-type: uint8
  91 ----
  92 ====
  93
  94 .Static array field type object: <<length-prop,22>>{nbsp}xref:str-ft-obj.adoc[strings].
  95 ====
  96 [source,yaml]
  97 ----
  98 class: static-array
  99 length: 22
 100 element-field-type:
 101   class: string
 102 ----
 103 ====
 104
 105 .Static array field type object: <<length-prop,five>> static arrays of 32{nbsp}double-precision xref:real-ft-obj.adoc[reals].
 106 ====
 107 [source,yaml]
 108 ----
 109 class: static-array
 110 length: 5
 111 element-field-type:
 112   class: static-array
 113   length: 32
 114   element-field-type:
 115     class: real
 116     size: 64
 117 ----
 118 ====