local function get_temp_name(arg,curr, length)
-- we don't want to use the temp dir, because graphics would be then generated outside of
-- the directory of the source document. so we will make
local tmp_name = os.tmpname()
if pos == sequence then
-- base tmp_name on the input name in the last step of sequence
-- so the generated images won't have random names
tmp_name = arg.input .. "-preprocess_input"
else
tmp_name = tmp_name:match("([^/\\]+)$")
end
return tmp_name
end
local function execute_sequence(sequence, arg, make)
-- keep track of all generated tmp files
local temp_files = {}
-- the temporary file for the current compilation step
-- should become the tex_file for the next one. It doesn't
-- matter that it isn't TeX file in some cases
local previous_temp
for pos, cmd_name in ipairs(sequence) do
local tmp_name = get_temp_name(arg,pos, #sequence)
temp_files[#temp_files+1] = tmp_name
-- make the temp file name accessible to the executed commands
arg.tmp_file = tmp_name
-- the current temporary file should become tex_file in the next step
-- in the first execution of the compilation sequence we will use the
-- actual input file name
arg.tex_file = previous_temp or arg.tex_file
previous_temp = tmp_name
-- get the command to execute
local cmd = commands[cmd_name]
-- fill the command template with make4ht arguments and execute
local command = cmd.command % arg
log:info(command)
mkutils.execute(command)
end
return temp_files
end
local function get_preprocessing_pipeline(input_file)
-- detect the file extension
local extension = input_file:match("%.(.-)$")
if not extension then return nil, "Cannot get extension: " .. input_file end
-- the table with file actions is case insensitive
-- the extension is converted to lowercase in order
-- to support both .rnw and .Rnw
extension = string.lower(extension)
local matched = filetypes[extension]
if not matched then return nil, "Unsupported extension: " .. extension end
return matched
end
-- join the make4ht params and command options tables
local function make_options(arg, command_options)
local options = {}
local command_options = command_options or {}
for k,v in pairs(arg) do options[k] = v end
for k,v in pairs(command_options) do options[k] = v end
return options
end
M.modify_build = function(make)
-- get access to the main arguments
local arg = make.params
-- get the execution sequence for the input format
local matched, msg = get_preprocessing_pipeline(arg.tex_file)
if not matched then
log:error("preprocess_input error: ".. msg)
return
end
-- prepare options
local options = make_options(arg, matched.options)
-- run the execution sequence
local temp_files = execute_sequence(matched.sequence or {}, options, make)
-- the last temporary file contains the actual TeX file
local last_temp_file = temp_files[#temp_files]
-- remove the intermediate temp files
if #temp_files > 2 then
for i = 1, #temp_files - 1 do
log:debug("Removing temporary file", temp_files[i])
os.remove(temp_files[i])
end
end
if last_temp_file then
-- update all commands in the .mk4 file with the temp file as tex_file
local update_params = function(cmd)
local params = cmd.params
params.tex_file = last_temp_file
params.is_tmp_file = true
end
for _, cmd in ipairs(make.build_seq) do
update_params(cmd)
end
-- also update the main params
update_params(make)
end
return make
end
