lib: add process logging

log() may be called to enable logging; log(nil) would turn it back off.  The
log will be opened in write-append mode, preserving existing contents.

Fixes #13

Signed-off-by: Kyle Evans <[email protected]>

lib/orch/actions.lua

@@ -82,6 +82,26 @@ actions.defined = {
 			return true
 		end,
 	},
+	log = {
+		init = function(action, args)
+			local file = args[1]
+			if type(file) == "string" then
+				file = io.open(file, "a+")
+			end
+
+			action.file = file
+		end,
+		execute = function(action)
+			local current_process = action.ctx.process
+
+			if not current_process then
+				error("execute() called before process spawned.")
+			end
+
+			current_process:logfile(action.file)
+			return true
+		end,
+	},
 	raw = {
 		init = function(action, args)
 			action.value = args[1]

lib/orch/process.lua

@@ -53,6 +53,10 @@ function MatchBuffer:refill(action, timeout)
 			return true
 		end
 
+		if self.process.log then
+			self.process.log:write(input)
+		end
+
 		self.buffer = self.buffer .. input
 		if type(action) == "table" then
 			return self:_matches(action)
@@ -111,20 +115,34 @@ function Process:read(func, timeout)
 		return self._process:read(func)
 	end
 end
-function Process:raw(text)
-	return self._process:raw(text)
+function Process:raw(is_raw)
+	self.is_raw = is_raw
+	return self._process:raw(is_raw)
 end
 function Process:write(data)
+	if self.log then
+		self.log:write(data)
+	end
 	return self._process:write(data)
 end
 function Process:close()
 	assert(self._process:close())
 
+	-- Flush output, close everything out
+	self:logfile(nil)
 	self._process = nil
 	self.term = nil
 	return true
 end
 -- Our own special salt
+function Process:logfile(file)
+	if self.log then
+		self.log:flush()
+		self.log:close()
+	end
+
+	self.log = file
+end
 function Process:match(action)
 	local buffer = self.buffer
 	if not buffer:match(action) then

man/orch.5

@@ -3,7 +3,7 @@
 .\"
 .\" SPDX-License-Identifier: BSD-2-Clause
 .\"
-.Dd January 27, 2024
+.Dd February 10, 2024
 .Dt ORCH 5
 .Os
 .Sh NAME
@@ -135,6 +135,14 @@ style hexdump output to stderr of the input
 .Pp
 This directive is always processed immediately, and is intended to be used
 within a failure context to aide in analysis of why a match failed.
+.It Fn log "logfile"
+Sets a logfile for subsequent input and output to the process.
+The
+.Fa logfile
+may be a string specifying a filename or an open file (for lib users).
+If a filename is specified, then
+.Nm
+will open it in write-append mode and preserve existing contents.
 .It Fn matcher "type"
 Changes the default matcher for subsequent match blocks to the type described
 by