[libcamera-devel] [PATCH v2 4/7] utils: ipc: Add support for Flags
Paul Elder
paul.elder at ideasonboard.com
Thu Aug 18 08:49:19 CEST 2022
Add Flags<E> as a supported type in the IPA interface.
It is used in mojom with the [Flags] attribute. Any field or parameter
type E that is prefixed with the [Flags] attribute will direct the code
generator to generate the type name "Flags<E>" and appropriate
serialization/deserialization code for Flags<E> instead of for E.
It is usable and has been tested in struct members, function input and
output parameters, and Signal parameters. This does not add support for
returning Flags as direct return values.
The [Flags] attribute can also be used on enum definitions, which will
instruct the code generator to convert it to an enum class instead of a
raw enum.
Signed-off-by: Paul Elder <paul.elder at ideasonboard.com>
---
Question for reviewers: Should we use a different attribute name to
specify that an enum should be an enum class?
My rationale here was that if you want to use an enum for Flags then you
put the [Flags] attribute on it, then it'll be generated as an enum
class, and just like how in C++ you have to wrap E in Flags<>, the
analogous form in mojom is the [Flags] attribute.
Also, I did try converting all enums to enum classes; it broke a lot of
raspberrypi stuff because they expect enums to be usable as both flags
and ints (as far as I could understand)...
Changes in v2:
- Use mojom attribute to specify that a field should be Flags<E>,
instead of using a magic type name format
---
include/libcamera/ipa/ipa_interface.h | 1 +
.../definition_functions.tmpl | 2 +-
.../libcamera_templates/proxy_functions.tmpl | 10 +++++---
.../libcamera_templates/serializer.tmpl | 4 ++++
.../generators/mojom_libcamera_generator.py | 23 ++++++++++++++++++-
5 files changed, 35 insertions(+), 5 deletions(-)
diff --git a/include/libcamera/ipa/ipa_interface.h b/include/libcamera/ipa/ipa_interface.h
index 50ca0e7b..8afcfe21 100644
--- a/include/libcamera/ipa/ipa_interface.h
+++ b/include/libcamera/ipa/ipa_interface.h
@@ -13,6 +13,7 @@
#include <map>
#include <vector>
+#include <libcamera/base/flags.h>
#include <libcamera/base/signal.h>
#include <libcamera/controls.h>
diff --git a/utils/ipc/generators/libcamera_templates/definition_functions.tmpl b/utils/ipc/generators/libcamera_templates/definition_functions.tmpl
index 94bb4918..fa185177 100644
--- a/utils/ipc/generators/libcamera_templates/definition_functions.tmpl
+++ b/utils/ipc/generators/libcamera_templates/definition_functions.tmpl
@@ -9,7 +9,7 @@
# \param enum Enum object whose definition is to be generated
#}
{%- macro define_enum(enum) -%}
-enum {{enum.mojom_name}} {
+enum{{" class" if enum|is_flags}} {{enum.mojom_name}} {
{%- for field in enum.fields %}
{{field.mojom_name}} = {{field.numeric_value}},
{%- endfor %}
diff --git a/utils/ipc/generators/libcamera_templates/proxy_functions.tmpl b/utils/ipc/generators/libcamera_templates/proxy_functions.tmpl
index cbcfb64a..2be65d43 100644
--- a/utils/ipc/generators/libcamera_templates/proxy_functions.tmpl
+++ b/utils/ipc/generators/libcamera_templates/proxy_functions.tmpl
@@ -62,7 +62,9 @@
{%- else %}
std::tie({{param.mojom_name}}Buf, std::ignore) =
{%- endif %}
-{%- if param|is_enum %}
+{%- if param|is_flags %}
+ IPADataSerializer<{{param|name_full}}>::serialize({{param.mojom_name}}
+{%- elif param|is_enum %}
IPADataSerializer<uint32_t>::serialize(static_cast<uint32_t>({{param.mojom_name}})
{%- else %}
IPADataSerializer<{{param|name}}>::serialize({{param.mojom_name}}
@@ -105,7 +107,9 @@
#}
{%- macro deserialize_param(param, pointer, loop, buf, fds, iter, data_size) -%}
{{"*" if pointer}}{{param.mojom_name}} =
-{%- if param|is_enum %}
+{%- if param|is_flags %}
+IPADataSerializer<{{param|name_full}}>::deserialize(
+{%- elif param|is_enum %}
static_cast<{{param|name_full}}>(IPADataSerializer<uint32_t>::deserialize(
{%- else %}
IPADataSerializer<{{param|name}}>::deserialize(
@@ -133,7 +137,7 @@ IPADataSerializer<{{param|name}}>::deserialize(
{%- if param|needs_control_serializer %}
&controlSerializer_
{%- endif -%}
-){{")" if param|is_enum}};
+){{")" if param|is_enum and not param|is_flags}};
{%- endmacro -%}
diff --git a/utils/ipc/generators/libcamera_templates/serializer.tmpl b/utils/ipc/generators/libcamera_templates/serializer.tmpl
index 77bae36f..eec75211 100644
--- a/utils/ipc/generators/libcamera_templates/serializer.tmpl
+++ b/utils/ipc/generators/libcamera_templates/serializer.tmpl
@@ -34,6 +34,8 @@
std::tie({{field.mojom_name}}, std::ignore) =
{%- if field|is_pod %}
IPADataSerializer<{{field|name}}>::serialize(data.{{field.mojom_name}});
+ {%- elif field|is_flags %}
+ IPADataSerializer<{{field|name_full}}>::serialize(data.{{field.mojom_name}});
{%- elif field|is_enum %}
IPADataSerializer<uint{{field|bit_width}}_t>::serialize(data.{{field.mojom_name}});
{%- endif %}
@@ -96,6 +98,8 @@
{{- check_data_size(field_size, 'dataSize', field.mojom_name, 'data')}}
{%- if field|is_pod %}
ret.{{field.mojom_name}} = IPADataSerializer<{{field|name}}>::deserialize(m, m + {{field_size}});
+ {%- elif field|is_flags %}
+ ret.{{field.mojom_name}} = IPADataSerializer<{{field|name_full}}>::deserialize(m, m + {{field_size}});
{%- else %}
ret.{{field.mojom_name}} = static_cast<{{field|name_full}}>(IPADataSerializer<uint{{field|bit_width}}_t>::deserialize(m, m + {{field_size}}));
{%- endif %}
diff --git a/utils/ipc/generators/mojom_libcamera_generator.py b/utils/ipc/generators/mojom_libcamera_generator.py
index 753bfc73..5534b24e 100644
--- a/utils/ipc/generators/mojom_libcamera_generator.py
+++ b/utils/ipc/generators/mojom_libcamera_generator.py
@@ -74,6 +74,8 @@ def GetDefaultValue(element):
return element.default
if type(element.kind) == mojom.Kind:
return '0'
+ if IsFlags(element):
+ return ''
if mojom.IsEnumKind(element.kind):
return f'static_cast<{element.kind.mojom_name}>(0)'
if isinstance(element.kind, mojom.Struct) and \
@@ -223,6 +225,15 @@ def IsEnum(element):
def IsFd(element):
return mojom.IsStructKind(element.kind) and element.kind.mojom_name == "SharedFD"
+def IsFlags(element):
+ if not hasattr(element, 'attributes'):
+ return False
+ if element.attributes is None:
+ return False
+ if 'Flags' in element.attributes:
+ return True
+ return False
+
def IsMap(element):
return mojom.IsMapKind(element.kind)
@@ -251,9 +262,13 @@ def ByteWidthFromCppType(t):
raise Exception('invalid type')
return str(int(_bit_widths[key]) // 8)
-
# Get the type name for a given element
def GetNameForElement(element):
+ # Flags
+ if IsFlags(element):
+ if mojom.IsEnumKind(element):
+ return element.mojom_name
+ return f'Flags<{GetFullNameForElement(element.kind)}>'
# structs
if (mojom.IsEnumKind(element) or
mojom.IsInterfaceKind(element) or
@@ -311,6 +326,11 @@ def GetFullNameForElement(element):
if namespace_str == '':
return name
+
+ if IsFlags(element):
+ name = re.match(r'^Flags<(.*)>$', name).group(1)
+ return f'Flags<{namespace_str}::{name}>'
+
return f'{namespace_str}::{name}'
def ValidateZeroLength(l, s, cap=True):
@@ -408,6 +428,7 @@ class Generator(generator.Generator):
'is_controls': IsControls,
'is_enum': IsEnum,
'is_fd': IsFd,
+ 'is_flags': IsFlags,
'is_map': IsMap,
'is_plain_struct': IsPlainStruct,
'is_pod': IsPod,
--
2.30.2
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