Re: git: 9ded074e875c - main - Refactor makesyscalls.lua into a library

On 10/30/24 16:08, Brooks Davis wrote:
> The branch main has been updated by brooks:
> 
> URL: https://cgit.FreeBSD.org/src/commit/?id=9ded074e875c29cb92d5f643801990d7bb23cca4
> 
> commit 9ded074e875c29cb92d5f643801990d7bb23cca4
> Author:     agge3 <sterspark@gmail.com>
> AuthorDate: 2024-10-21 21:42:13 +0000
> Commit:     Brooks Davis <brooks@FreeBSD.org>
> CommitDate: 2024-10-30 21:04:30 +0000
> 
>      Refactor makesyscalls.lua into a library
>      
>      * main.lua replicates the functionality of makesyscalls.lua
>      * Individual files are generated by their associated module
>        * Modules can be called as standalone scripts to generate a specific
>          file
>      * Data and procedures are performed by objects instead of procedual code
>      * Bitmasks are replaced by declarative types
>      * Temporary files are no longer produced, writing is stored in memory
>      * Comments provide explanation to functions and semantics
>      
>      Google Summer of Code 2024 Final Work Product
>      
>      Co-authored-by: Warner Losh <imp@freebsd.org>
>      Co-authored-by: Kyle Evans <kevans@freebsd.org>
>      Co-authored-by: Brooks Davis <brooks@freebsd.org>
>      Sponsored by:    Google (GSoC 24)
>      Pull Request:   https://github.com/freebsd/freebsd-src/pull/1362
>      Signed-off-by: agge3 <sterspark@gmail.com>
> ---
>   sys/tools/syscalls/README.md                 |  49 +++
>   sys/tools/syscalls/config.lua                | 312 +++++++++++++++++
>   sys/tools/syscalls/core/freebsd-syscall.lua  | 147 ++++++++
>   sys/tools/syscalls/core/scarg.lua            | 163 +++++++++
>   sys/tools/syscalls/core/scret.lua            |  45 +++
>   sys/tools/syscalls/core/syscall.lua          | 497 +++++++++++++++++++++++++++
>   sys/tools/syscalls/main.lua                  |  64 ++++
>   sys/tools/syscalls/scripts/init_sysent.lua   | 193 +++++++++++
>   sys/tools/syscalls/scripts/libsys_h.lua      | 111 ++++++
>   sys/tools/syscalls/scripts/syscall_h.lua     |  97 ++++++
>   sys/tools/syscalls/scripts/syscall_mk.lua    |  90 +++++
>   sys/tools/syscalls/scripts/syscalls.lua      | 109 ++++++
>   sys/tools/syscalls/scripts/syscalls_map.lua  |  74 ++++
>   sys/tools/syscalls/scripts/sysproto_h.lua    | 242 +++++++++++++
>   sys/tools/syscalls/scripts/systrace_args.lua | 268 +++++++++++++++
>   sys/tools/syscalls/tools/generator.lua       | 113 ++++++
>   sys/tools/syscalls/tools/util.lua            | 194 +++++++++++
>   17 files changed, 2768 insertions(+)
> 
 > [...]
> diff --git a/sys/tools/syscalls/core/freebsd-syscall.lua b/sys/tools/syscalls/core/freebsd-syscall.lua
> new file mode 100644
> index 000000000000..193b1e43563c
> --- /dev/null
> +++ b/sys/tools/syscalls/core/freebsd-syscall.lua
> @@ -0,0 +1,147 @@
 > [...]
> +function FreeBSDSyscall:parseSysfile()
> +	local file = self.sysfile
> +	local config = self.config
> +	local commentExpr = "^%s*;.*"
> +
> +	if file == nil then
> +		return nil, "No file given"
> +	end
> +
> +	self.syscalls = {}
> +
> +	local fh, msg = io.open(file)
> +	if fh == nil then
> +		return nil, msg
> +	end
> +
> +	local incs = ""
> +	local defs = ""
> +	local s
> +	for line in fh:lines() do
> +		line = line:gsub(commentExpr, "") -- Strip any comments.
> +		-- NOTE: Can't use pure pattern matching here because of
> +		-- the 's' test and this is shorter than a generic pattern
> +		-- matching pattern.
> +		if line == nil or line == "" then
> +			goto skip	-- Blank line, skip this line.
> +		elseif s ~= nil then
> +			-- If we have a partial system call object s,
> +			-- then feed it one more line.
> +			if s:add(line) then
> +				-- Append to system call list.
> +				for t in s:iter() do
> +					if t:validate(t.num - 1) then
> +						table.insert(self.syscalls, t)
> +					else
> +						util.abort(1,
> +						    "Skipped system call " ..
> +						    "at number " .. t.num)
> +					end
> +				end
> +				s = nil
> +			end
> +		elseif line:match("^#%s*include") then
> +			incs = incs .. line .. "\n"
> +		elseif line:match("%%ABI_HEADERS%%") then
> +			local h = self.config.abi_headers
> +			if h ~= nil and h ~= "" then
> +				incs = incs .. h .. "\n"
> +			end
> +		elseif line:match("^#%s*define") then
> +			defs = defs .. line.. "\n"
> +		elseif line:match("^#") then
> +			util.abort(1, "Unsupported cpp op " .. line)

This specifically is kind of a huge regression, and I don't really know 
how to cope with it.  We've guaranteed for years that we'll copy 
preprocessor directives through to all output files.  We don't use that 
upstream in FreeBSD, but we work with downstreams/vendors that make 
extensive use of it in their syscall definitions.

I don't really know what the answer is to this, but we probably 
shouldn't have dropped it without some discussion first.  This is going 
to be a bit of a headache...

 > [...]

Thanks,

Kyle Evans