gstreamer-rs/gstreamer/src/caps_serde.rs
2020-11-22 19:15:20 +02:00

516 lines
17 KiB
Rust

// Copyright (C) 2018 François Laignel <fengalin@free.fr>
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
// option. This file may not be copied, modified, or distributed
// except according to those terms.
use serde::de;
use serde::de::{Deserialize, Deserializer, EnumAccess, SeqAccess, VariantAccess, Visitor};
use serde::ser::{Serialize, SerializeSeq, SerializeTuple, Serializer};
use std::fmt;
use crate::Caps;
use crate::CapsFeatures;
use crate::CapsFeaturesRef;
use crate::CapsRef;
use crate::Structure;
use crate::StructureRef;
enum CapsVariantKinds {
Any,
Empty,
Some,
}
const CAPS_VARIANT_ANY_ID: u32 = 0;
const CAPS_VARIANT_ANY_STR: &str = "Any";
const CAPS_VARIANT_EMPTY_ID: u32 = 1;
const CAPS_VARIANT_EMPTY_STR: &str = "Empty";
const CAPS_VARIANT_SOME_ID: u32 = 2;
const CAPS_VARIANT_SOME_STR: &str = "Some";
const CAPS_VARIANT_NAMES: &[&str] = &[
&CAPS_VARIANT_ANY_STR,
&CAPS_VARIANT_EMPTY_STR,
&CAPS_VARIANT_SOME_STR,
];
struct CapsItemSe<'a>(&'a StructureRef, Option<&'a CapsFeaturesRef>);
impl<'a> Serialize for CapsItemSe<'a> {
fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
let mut tup = serializer.serialize_tuple(2)?;
tup.serialize_element(self.0)?;
tup.serialize_element(&self.1)?;
tup.end()
}
}
struct CapsForIterSe<'a>(&'a CapsRef);
impl<'a> Serialize for CapsForIterSe<'a> {
fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
let iter = self.0.iter_with_features();
let size = iter.size_hint().0;
if size > 0 {
let mut seq = serializer.serialize_seq(Some(size))?;
for (structure, features) in iter {
let features = if !features.is_any()
&& features.is_equal(crate::CAPS_FEATURES_MEMORY_SYSTEM_MEMORY.as_ref())
{
None
} else {
Some(features)
};
seq.serialize_element(&CapsItemSe(structure, features))?;
}
seq.end()
} else {
let seq = serializer.serialize_seq(None)?;
seq.end()
}
}
}
impl Serialize for CapsRef {
fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
if self.is_any() {
serializer.serialize_unit_variant(
stringify!(Caps),
CAPS_VARIANT_ANY_ID,
CAPS_VARIANT_ANY_STR,
)
} else if self.is_empty() {
serializer.serialize_unit_variant(
stringify!(Caps),
CAPS_VARIANT_EMPTY_ID,
CAPS_VARIANT_EMPTY_STR,
)
} else {
serializer.serialize_newtype_variant(
stringify!(Caps),
CAPS_VARIANT_SOME_ID,
CAPS_VARIANT_SOME_STR,
&CapsForIterSe(&self),
)
}
}
}
impl Serialize for Caps {
fn serialize<S: Serializer>(&self, serializer: S) -> Result<S::Ok, S::Error> {
self.as_ref().serialize(serializer)
}
}
struct CapsItemDe(Structure, Option<CapsFeatures>);
struct CapsItemVisitor;
impl<'de> Visitor<'de> for CapsItemVisitor {
type Value = CapsItemDe;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a tuple `(Structure, Option<CapsFeature>)`")
}
fn visit_seq<A: SeqAccess<'de>>(self, mut seq: A) -> Result<Self::Value, A::Error> {
let structure = seq
.next_element::<Structure>()?
.ok_or_else(|| de::Error::custom("Expected a `Structure` for `Caps` item"))?;
let features_option = seq.next_element::<Option<CapsFeatures>>()?.ok_or_else(|| {
de::Error::custom("Expected an `Option<CapsFeature>` for `Caps` item")
})?;
Ok(CapsItemDe(structure, features_option))
}
}
impl<'de> Deserialize<'de> for CapsItemDe {
fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<CapsItemDe, D::Error> {
skip_assert_initialized!();
deserializer.deserialize_tuple(2, CapsItemVisitor)
}
}
struct CapsSome(Caps);
struct CapsSomeVisitor;
impl<'de> Visitor<'de> for CapsSomeVisitor {
type Value = CapsSome;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a sequence of `(Structure, Option<CapsFeature>)`")
}
fn visit_seq<A: SeqAccess<'de>>(self, mut seq: A) -> Result<Self::Value, A::Error> {
let mut caps = Caps::new_empty();
{
let caps = caps.get_mut().unwrap();
while let Some(caps_item) = seq.next_element::<CapsItemDe>()? {
caps.append_structure_full(caps_item.0, caps_item.1);
}
}
Ok(CapsSome(caps))
}
}
impl<'de> Deserialize<'de> for CapsSome {
fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<CapsSome, D::Error> {
skip_assert_initialized!();
deserializer.deserialize_seq(CapsSomeVisitor)
}
}
struct CapsVariantKindsVisitor;
impl<'de> Visitor<'de> for CapsVariantKindsVisitor {
type Value = CapsVariantKinds;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a Caps variant kind (`Any`, `None` or `Some`)")
}
fn visit_u32<E: de::Error>(self, value: u32) -> Result<Self::Value, E> {
match value {
CAPS_VARIANT_ANY_ID => Ok(CapsVariantKinds::Any),
CAPS_VARIANT_EMPTY_ID => Ok(CapsVariantKinds::Empty),
CAPS_VARIANT_SOME_ID => Ok(CapsVariantKinds::Some),
_ => Err(de::Error::invalid_value(
de::Unexpected::Unsigned(u64::from(value)),
&self,
)),
}
}
fn visit_str<E: de::Error>(self, value: &str) -> Result<Self::Value, E> {
match value {
CAPS_VARIANT_ANY_STR => Ok(CapsVariantKinds::Any),
CAPS_VARIANT_EMPTY_STR => Ok(CapsVariantKinds::Empty),
CAPS_VARIANT_SOME_STR => Ok(CapsVariantKinds::Some),
_ => Err(de::Error::unknown_variant(value, CAPS_VARIANT_NAMES)),
}
}
}
impl<'de> Deserialize<'de> for CapsVariantKinds {
fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
skip_assert_initialized!();
deserializer.deserialize_identifier(CapsVariantKindsVisitor)
}
}
struct CapsVisitor;
impl<'de> Visitor<'de> for CapsVisitor {
type Value = Caps;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
formatter.write_str("a Caps enum (`Any`, `None` or `Some()`)")
}
fn visit_enum<A: EnumAccess<'de>>(self, data: A) -> Result<Self::Value, A::Error> {
let res = match data.variant()? {
(CapsVariantKinds::Any, _v) => Caps::new_any(),
(CapsVariantKinds::Empty, _v) => Caps::new_empty(),
(CapsVariantKinds::Some, v) => v
.newtype_variant::<CapsSome>()
.map(|caps_some| caps_some.0)?,
};
Ok(res)
}
}
impl<'de> Deserialize<'de> for Caps {
fn deserialize<D: Deserializer<'de>>(deserializer: D) -> Result<Self, D::Error> {
skip_assert_initialized!();
deserializer.deserialize_enum(stringify!(Caps), CAPS_VARIANT_NAMES, CapsVisitor)
}
}
#[cfg(test)]
mod tests {
use crate::Array;
use crate::Caps;
use crate::CapsFeatures;
use crate::Fraction;
#[test]
fn test_serialize() {
crate::init().unwrap();
let caps = Caps::builder("foo/bar")
.field("int", &12)
.field("bool", &true)
.field("string", &"bla")
.field("fraction", &Fraction::new(1, 2))
.field("array", &Array::new(&[&1, &2]))
.build();
let mut pretty_config = ron::ser::PrettyConfig::default();
pretty_config.new_line = "".to_string();
let res = ron::ser::to_string_pretty(&caps, pretty_config);
assert_eq!(
Ok(concat!(
"Some([",
" ((\"foo/bar\", [",
" (\"int\", \"i32\", 12),",
" (\"bool\", \"bool\", true),",
" (\"string\", \"String\", Some(\"bla\")),",
" (\"fraction\", \"Fraction\", (1, 2)),",
" (\"array\", \"Array\", [",
" (\"i32\", 1),",
" (\"i32\", 2),",
" ]),",
" ]), None),",
"])"
)
.to_owned()),
res,
);
let caps = Caps::builder("foo/bar")
.field("int", &12)
.field("bool", &true)
.field("string", &"bla")
.field("fraction", &Fraction::new(1, 2))
.field("array", &Array::new(&[&1, &2]))
.features(&["foo:bar", "foo:baz"])
.build();
let mut pretty_config = ron::ser::PrettyConfig::default();
pretty_config.new_line = "".to_string();
let res = ron::ser::to_string_pretty(&caps, pretty_config);
assert_eq!(
Ok(concat!(
"Some([",
" ((\"foo/bar\", [",
" (\"int\", \"i32\", 12),",
" (\"bool\", \"bool\", true),",
" (\"string\", \"String\", Some(\"bla\")),",
" (\"fraction\", \"Fraction\", (1, 2)),",
" (\"array\", \"Array\", [",
" (\"i32\", 1),",
" (\"i32\", 2),",
" ]),",
" ]), Some(Some([",
" \"foo:bar\",",
" \"foo:baz\",",
" ]))),",
"])"
)
.to_owned()),
res,
);
let caps = Caps::builder("foo/bar")
.field("int", &12)
.field("bool", &true)
.field("string", &"bla")
.field("fraction", &Fraction::new(1, 2))
.field("array", &Array::new(&[&1, &2]))
.any_features()
.build();
let mut pretty_config = ron::ser::PrettyConfig::default();
pretty_config.new_line = "".to_string();
let res = ron::ser::to_string_pretty(&caps, pretty_config.clone());
assert_eq!(
Ok(concat!(
"Some([",
" ((\"foo/bar\", [",
" (\"int\", \"i32\", 12),",
" (\"bool\", \"bool\", true),",
" (\"string\", \"String\", Some(\"bla\")),",
" (\"fraction\", \"Fraction\", (1, 2)),",
" (\"array\", \"Array\", [",
" (\"i32\", 1),",
" (\"i32\", 2),",
" ]),",
" ]), Some(Any)),",
"])"
)
.to_owned()),
res,
);
let caps_any = Caps::new_any();
let res = ron::ser::to_string_pretty(&caps_any, pretty_config.clone());
assert_eq!(Ok("Any".to_owned()), res);
let caps_empty = Caps::new_empty();
let res = ron::ser::to_string_pretty(&caps_empty, pretty_config);
assert_eq!(Ok("Empty".to_owned()), res);
}
#[test]
fn test_deserialize() {
use crate::Structure;
crate::init().unwrap();
let caps_ron = "Any";
let caps: Caps = ron::de::from_str(caps_ron).unwrap();
assert!(caps.is_any());
let caps_ron = "Empty";
let caps: Caps = ron::de::from_str(caps_ron).unwrap();
assert!(caps.is_empty());
let caps_ron = r#"
Some([
(
("foo/bar", [
("int", "i32", 12),
("bool", "bool", true),
("string", "String", Some("bla")),
("fraction", "Fraction", (1, 2)),
("array", "Array", [
("i32", 1),
("i32", 2),
]),
]),
None,
),
])"#;
let caps: Caps = ron::de::from_str(caps_ron).unwrap();
let s = caps.get_structure(0).unwrap();
assert_eq!(
s,
Structure::new(
"foo/bar",
&[
("int", &12),
("bool", &true),
("string", &"bla"),
("fraction", &Fraction::new(1, 2)),
("array", &Array::new(&[&1, &2])),
],
)
.as_ref()
);
let caps_ron = r#"
Some([
(
("foo/bar", [
("int", "i32", 12),
("bool", "bool", true),
("string", "String", None),
("fraction", "Fraction", (1, 2)),
("array", "Array", [
("i32", 1),
("i32", 2),
]),
]),
Some(Some(["foo:bar", "foo:baz"])),
),
])"#;
let caps: Caps = ron::de::from_str(caps_ron).unwrap();
let s = caps.get_structure(0).unwrap();
let str_none: Option<&str> = None;
assert_eq!(
s,
Structure::new(
"foo/bar",
&[
("int", &12),
("bool", &true),
("string", &str_none),
("fraction", &Fraction::new(1, 2)),
("array", &Array::new(&[&1, &2])),
],
)
.as_ref()
);
let f = caps.get_features(0).unwrap();
assert!(f.is_equal(CapsFeatures::new(&["foo:bar", "foo:baz"]).as_ref()));
let caps_ron = r#"
Some([
(
("foo/bar", [
("int", "i32", 12),
("bool", "bool", true),
("string", "String", Some("bla")),
("fraction", "Fraction", (1, 2)),
("array", "Array", [
("i32", 1),
("i32", 2),
]),
]),
Some(Any),
),
])"#;
let caps: Caps = ron::de::from_str(caps_ron).unwrap();
let s = caps.get_structure(0).unwrap();
assert_eq!(
s,
Structure::new(
"foo/bar",
&[
("int", &12),
("bool", &true),
("string", &"bla"),
("fraction", &Fraction::new(1, 2)),
("array", &Array::new(&[&1, &2])),
],
)
.as_ref()
);
let f = caps.get_features(0).unwrap();
assert!(f.is_any());
}
#[test]
fn test_serde_roundtrip() {
crate::init().unwrap();
let caps = Caps::new_any();
let caps_ser = ron::ser::to_string(&caps).unwrap();
let caps_de: Caps = ron::de::from_str(caps_ser.as_str()).unwrap();
assert!(caps_de.is_any());
let caps = Caps::new_empty();
let caps_ser = ron::ser::to_string(&caps).unwrap();
let caps_de: Caps = ron::de::from_str(caps_ser.as_str()).unwrap();
assert!(caps_de.is_empty());
let caps = Caps::builder("foo/bar")
.field("int", &12)
.field("bool", &true)
.field("string", &"bla")
.field("fraction", &Fraction::new(1, 2))
.field("array", &Array::new(&[&1, &2]))
.build();
let caps_ser = ron::ser::to_string(&caps).unwrap();
let caps_de: Caps = ron::de::from_str(caps_ser.as_str()).unwrap();
assert!(caps_de.is_strictly_equal(&caps));
let caps = Caps::builder("foo/bar")
.field("int", &12)
.field("bool", &true)
.field("string", &"bla")
.field("fraction", &Fraction::new(1, 2))
.field("array", &Array::new(&[&1, &2]))
.features(&["foo:bar", "foo:baz"])
.build();
let caps_ser = ron::ser::to_string(&caps).unwrap();
let caps_de: Caps = ron::de::from_str(caps_ser.as_str()).unwrap();
assert!(caps_de.is_strictly_equal(&caps));
let caps = Caps::builder("foo/bar")
.field("int", &12)
.field("bool", &true)
.field("string", &"bla")
.field("fraction", &Fraction::new(1, 2))
.field("array", &Array::new(&[&1, &2]))
.any_features()
.build();
let caps_ser = ron::ser::to_string(&caps).unwrap();
let caps_de: Caps = ron::de::from_str(caps_ser.as_str()).unwrap();
assert!(caps_de.is_strictly_equal(&caps));
}
}