GeezerVison

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According to the FreeBSD manual page:

The getrandom() system call first appeared in FreeBSD 12.0.

According to the FreeBSD manual page:

The getrandom() system call first appeared in FreeBSD 12.0.

Yup, FreeBSD since 12.0 (December 2018), and NetBSD since 10.0 (March 2024) both claim to support the syscall now. I've not tested this on NetBSD, but their documentation is similar to FreeBSD's.

To satisfy my own curiosity I checked DragonFly and OpenBSD's documentation too. DragonFly claims support as of version 5.7. OpenBSD does not claim support, so if it has it it's undocumented, but OpenBSD's man pages are usually complete.

@serhiy-storchaka: I didn't understand your comment. Which code should be made similar to Python/bootstrap_hash.c?

I wasn't sure either. The code in bootstrap_hash.c already does the right thing, so I added a note about the BSDs.

I meant that the code in Python/bootstrap_hash.c already supports sys/random.h (and it is presumably tested), so it would be better to just copy it from Python/bootstrap_hash.c to Modules/posixmodule.c.

I meant that the code in Python/bootstrap_hash.c already supports sys/random.h (and it is presumably tested), so it would be better to just copy it from Python/bootstrap_hash.c to Modules/posixmodule.c.

Ah, okay, that makes sense. You're suggesting I make Modules/posixmodule.c look like Python/bootstrap_hash.c, keeping Python/bootstrap_hash.c unmodified? I interpreted your suggestion as making modifications to Python/bootstrap_hash.c to reflect the current changes to Modules/posixmodule.c.

@serhiy-storchaka: with this change, Modules/posixmodule.c and Python/bootstrap_hash.c use the same includes. The change LGTM. I don't see what else should be done. I suggest merging the change as it is.

Linux getrandom() manual page mentions #include <sys/random.h>: https://man7.org/linux/man-pages/man2/getrandom.2.html

//#ifndef MS_WINDOWS
#  ifdef HAVE_LINUX_RANDOM_H
#    include <linux/random.h>     // GRND_NONBLOCK
#  endif
#  if defined(HAVE_SYS_RANDOM_H) && (defined(HAVE_GETRANDOM) || defined(HAVE_GETENTROPY))
#    include <sys/random.h>       // getrandom()
#  endif
#  if !defined(HAVE_GETRANDOM) && defined(HAVE_GETRANDOM_SYSCALL)
#    include <sys/syscall.h>      // SYS_getrandom
#  endif

The proposed code:

#ifdef HAVE_SYS_RANDOM_H
#  include <sys/random.h>         // GRND_RANDOM on FreeBSD and NetBSD
#endif
#ifdef HAVE_LINUX_RANDOM_H
#  include <linux/random.h>       // GRND_RANDOM
#endif
#ifdef HAVE_GETRANDOM_SYSCALL
#  include <sys/syscall.h>        // syscall()
#endif

They are not identical. Different order of includes. Different conditions. I suggest to make them identical, so we will not introduce subtle bugs in future.

Also, if the code in Python/bootstrap_hash.c already works, are changes in configure required?

@dankm: Can you apply @serhiy-storchaka's suggestions?

Well that's what I get for not testing a proposed change, I'll fix it in the morning.

"Merge branch 'main' into dankm/getrandom": please avoid that unless there is a good reason to do that.

Noted for the future. If figured it might be the way to get past some failures on MacOS I was seeing with my previous update.

Currently on my FreeBSD 15 (VM), HAVE_GETRANDOM_SYSCALL macro is not defined in pyconfig.h and so there is no os.getrandom() function.

With this change, the HAVE_GETRANDOM_SYSCALL macro macro is defined in pyconfig.h and Python has an os.getrandom() function. The change works as expected.

Note: I had to remove my configure cache to update properly the HAVE_GETRANDOM_SYSCALL macro.

This PR is stale because it has been open for 30 days with no activity.