@@ -104,6 +104,68 @@ it hit version 0.28 which added new functionality and improved existing:
104104
105105## Library Updates
106106
107+ ### [ presser]
108+
109+ [ presser] ([ GitHub] [ docs.rs] ) by [ @fu5ha ] ([ Embark Studios] )
110+ is a crate to help you copy things into raw buffers without
111+ invoking spooky action at a distance (undefined behavior).
112+
113+ Ever done something like this?
114+
115+ ``` rust
116+ #[derive(Clone , Copy )]
117+ #[repr(C )]
118+ struct MyDataStruct {
119+ a : u8 ,
120+ b : u32 ,
121+ }
122+
123+ let my_data = MyDataStruct { a : 0 , b : 42 };
124+
125+ // 🚨 MyDataStruct contains 3 padding bytes after `a`, which are
126+ // uninit, therefore getting a slice that includes them is UB!
127+ let my_data_bytes : & [u8 ] = transmute (& my_data );
128+
129+ // allocate an uninit buffer of some size
130+ let my_buffer : MyBufferType = some_api . alloc_buffer_size (2048 );
131+
132+ // 🚨 this is UB for the same reason, these bytes are uninit!*
133+ let buffer_as_bytes : & mut [u8 ] =
134+ slice :: from_raw_parts (my_buffer . ptr (), my_buffer . size ());
135+
136+ // 🚨 this is UB because not only are both slices invalid,
137+ // this is not ensuring proper alignment!
138+ buffer_as_bytes . copy_from_slice (my_data_bytes );
139+ ```
140+
141+ [ presser] can help.
142+
143+ ``` rust
144+ // borrow our raw allocation as a presser::Slab, asserting we have
145+ // unique access to it. see the docs for more.
146+ let slab = unsafe { raw_allocation . borrow_as_slab (); }
147+
148+ // now we may safely copy `my_data` into `my_buffer`,
149+ // starting at a minimum offset of 0 into the buffer
150+ let copy_record = presser :: copy_to_offset (& my_data , & mut slab , 0 )? ;
151+ ```
152+
153+ If you're not convinced this is actually an issue, read more in the
154+ [ crate readme] . If you're intrigued and want to know more,
155+ see the [ docs] .
156+
157+ _ Discussions: [ /r/rust] , [ Twitter] _
158+
159+ [ presser ] : https://crates.io/crates/presser
160+ [ GitHub ] : https://github.com/embarkstudios/presser
161+ [ docs.rs ] : https://docs.rs/presser
162+ [ @fu5ha ] : https://github.com/fu5ha
163+ [ Embark Studios ] : https://github.com/embarkstudios
164+ [ crate readme ] : https://crates.io/crates/presser
165+ [ docs ] : https://docs.rs/presser
166+ [ Twitter ] : https://twitter.com/fu5ha/status/1581705656218062848
167+ [ /r/rust ] : https://www.reddit.com/r/rust/comments/y5mq3w/presser_a_crate_to_help_you_copy_things_into_raw/
168+
107169## Popular Workgroup Issues in Github
108170
109171<!-- Up to 10 links to interesting issues -->
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