util: Allow FastRandomContext::randbytes for std::byte, Allow std::byte serialization #28012

1. 
   MarcoFalke commented at 10:14 am on June 30, 2023: member

   I need this for some stuff, but it should also be useful by itself for other developers that need it.
2. Allow FastRandomContext::randbytes for all byte types fade43edc4
3. Allow std::byte serialization fac6af16f4
4. 
   DrahtBot commented at 10:14 am on June 30, 2023: contributor

   The following sections might be updated with supplementary metadata relevant to reviewers and maintainers.

   Reviews

   See the guideline for information on the review process.

   Type	Reviewers
   ACK	sipa, dergoegge

   If your review is incorrectly listed, please react with 👎 to this comment and the bot will ignore it on the next update.

5. DrahtBot renamed this:
   util: Allow FastRandomContext::randbytes for std::byte, Allow std::byte serialization
   util: Allow FastRandomContext::randbytes for std::byte, Allow std::byte serialization
   on Jun 30, 2023
6. DrahtBot added the label Utils/log/libs on Jun 30, 2023
7. 
   sipa commented at 6:27 pm on June 30, 2023: member

   utACK fac6af16f4a254458b8cb3522317422b40362f8d

   The two commits feel quite unrelated here, though, but both seem fine to me.

8. dergoegge approved
9. 
   dergoegge commented at 8:33 am on July 7, 2023: member

   Code review ACK fac6af16f4a254458b8cb3522317422b40362f8d
10. fanquake merged this on Jul 7, 2023
11. fanquake closed this on Jul 7, 2023

    ---

12. sidhujag referenced this in commit b3c7e68a27 on Jul 7, 2023
13. MarcoFalke deleted the branch on Jul 8, 2023
14. in src/random.h:215 in fac6af16f4

    210@@ -211,7 +211,8 @@ class FastRandomContext
    211     }
    212 
    213     /** Generate random bytes. */
    214-    std::vector<unsigned char> randbytes(size_t len);
    215+    template <typename B = unsigned char>
    216+    std::vector<B> randbytes(size_t len);
    

    ---

    ---

    

    jonatack commented at 5:32 pm on July 12, 2023:

    Why this change? It is currently unused, “I need this for some stuff” is vague, and this change is being cited in #27425 (review) as a reason not to use rand test helpers consistently.

    ---

    

    MarcoFalke commented at 5:39 pm on July 12, 2023:

    std::byte is used in many places to pass bytes. Adding this helper makes it easier to fill a vector with std::bytes. For example, it is used in 9999a49b3299bd25dde4805f5c68adef3876057f (https://github.com/bitcoin/bitcoin/pull/28060). But the helper can also be used in other places.

    ---

    

    jonatack commented at 5:43 pm on July 12, 2023:

    Thank you for clarifying for me.

Contributors
MarcoFalke DrahtBot sipa dergoegge jonatack

Labels
Utils/log/libs