usb: unify handling of length parameters #177
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The length parameters in USB packets are strict and the existing implementation does already hardcode the length within the serialize functions. Therefore the user should not provide these lengths during creation time. In order to make this more verbose use defaults values within the structs and reference these defaults values within the serialization functions. It's not possible to remove these fields completly as this fields are used within deserialization from the hardware itself. Signed-off-by: Tobias Kohlbau <tobias@kohlbau.de>
core/src/core/usb.zig
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| @@ -530,7 +530,7 @@ pub const EndpointDescriptor = extern struct { | |||
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| pub fn serialize(self: *const @This()) [7]u8 { | |||
| var out: [7]u8 = undefined; | |||
| out[0] = 7; // length | |||
| out[0] = self.length; | |||
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This function should assert self.length to be 7, and hardcode it with either @sizeOf(@This()) or use out.len.
Otherwise, a user could pass in a bad self which has length = 6 or similar.
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That a pretty good idea, will implement it.
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Only out.len is possible as the size is reported with padding, which is not correct.
during the serialization and therefore is already hardcoded. The only other convinience is the calculation of the descriptor size, but this is already wrong. extern structs are padded and therefore do not have the right sizes. Signed-off-by: Tobias Kohlbau <tobias@kohlbau.de>
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I've updated https://github.com/tobiaskohlbau/microzig/tree/main and both commits are there, looks like GitHub has issues (https://www.githubstatus.com/), most likely therefore there is no information within this PR. If this remains an issue I will force-push my branch in order to trigger the events. |
Signed-off-by: Tobias Kohlbau <tobias@kohlbau.de>
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Looks like the CI needs a retry, maybe GitHub still has issues?
https://github.com/ZigEmbeddedGroup/microzig/actions/runs/8054829310/job/22000295495?pr=177 |
The length parameters in USB packets are strict and the existing implementation does already hardcode the length within the serialize functions. Therefore the user should not provide these lengths during creation time. In order to make this more verbose use defaults values within the structs and reference these defaults values within the serialization functions. It's not possible to remove these fields completly as this fields are used within deserialization from the hardware itself.