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annotate framework/env/execute/command.lua @ 486:7d53e12f0804

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New function execute.command{...}
author jbe
date Sun Jun 11 23:27:17 2017 +0200 (2017-06-11)
parents
children 91d0c8304d74
rev   line source
jbe@486 1 --[[--
jbe@486 2 output, -- collected data from stdout if process exited successfully
jbe@486 3 errmsg = -- error message if execution failed or if process didn't exit successfully
jbe@486 4 execute.command{
jbe@486 5 command = { filename, arg1, arg2, ... }, -- command and arguments
jbe@486 6 stdin_data = stdin_data, -- optional data to be sent to process via stdin
jbe@486 7 stdout_result_handler = stdout_result_handler, -- callback receiving: stdout data, success boolean, optional error message
jbe@486 8 stderr_line_handler = stderr_line_handler, -- callback for processing stderr line-wise
jbe@486 9 exit_handler = exit_handler, -- callback when process exited
jbe@486 10 signal_handler = signal_handler, -- callback when process terminated due to signal
jbe@486 11 timeout_handler = timeout_handler, -- callback when process gets killed due to timeout
jbe@486 12 abort_handler = abort_handler, -- callback when process gets killed due to request by poll function
jbe@486 13 abortable = abortable, -- set to true if process shall be terminated if poll function requests termination
jbe@486 14 poll = poll, -- alternative poll command with moonbridge_io.poll(...) semantics
jbe@486 15 db = db, -- database handle for waiting for notifies
jbe@486 16 db_notify_handler = db_notify_handler -- handler for database notifications which may return true to kill process
jbe@486 17 }
jbe@486 18
jbe@486 19 --]]--
jbe@486 20
jbe@486 21 function execute.command(args)
jbe@486 22
jbe@486 23 local moonbridge_io = require("moonbridge_io")
jbe@486 24 local poll = args.poll or moonbridge_io.poll
jbe@486 25
jbe@486 26 local start = moonbridge_io.timeref()
jbe@486 27 local process, errmsg = moonbridge_io.exec(table.unpack(args.command))
jbe@486 28 if not process then return nil, errmsg end
jbe@486 29
jbe@486 30 local stdout_chunks, stderr_chunks = {}, {}
jbe@486 31 local read_fds = {[process.stdout] = true, [process.stderr] = true}
jbe@486 32 local write_fds = {[process.stdin] = true}
jbe@486 33 if args.db then
jbe@486 34 read_fds[args.db.fd] = true
jbe@486 35 end
jbe@486 36
jbe@486 37 local function return_error(errmsg)
jbe@486 38 if args.stdout_result_handler then
jbe@486 39 args.stdout_result_handler(table.concat(stdout_chunks), false, errmsg)
jbe@486 40 end
jbe@486 41 return nil, errmsg
jbe@486 42 end
jbe@486 43
jbe@486 44 local function write(...)
jbe@486 45 if write_fds[process.stdin] then
jbe@486 46 local buffered = process.stdin:flush_nb(...)
jbe@486 47 if not buffered or buffered == 0 then
jbe@486 48 process.stdin:close()
jbe@486 49 write_fds[process.stdin] = nil
jbe@486 50 end
jbe@486 51 end
jbe@486 52 end
jbe@486 53 write(args.stdin_data or "")
jbe@486 54
jbe@486 55 while
jbe@486 56 read_fds[process.stdout] or read_fds[process.stderr] or
jbe@486 57 write_fds[process.stdin]
jbe@486 58 do
jbe@486 59 local timeout = args.timeout and args.timeout-moonbridge_io.timeref(start)
jbe@486 60 local pollstatus, pollmsg, pollterm =
jbe@486 61 poll(read_fds, write_fds, timeout, args.abortable)
jbe@486 62 if not pollstatus then
jbe@486 63 process:kill():wait()
jbe@486 64 if pollterm then
jbe@486 65 if args.abort_handler then args.abort_handler() end
jbe@486 66 else
jbe@486 67 if args.timeout_handler then args.timeout_handler() end
jbe@486 68 end
jbe@486 69 return return_error(pollmsg)
jbe@486 70 end
jbe@486 71 if args.db then
jbe@486 72 local channel, payload, pid = db:wait(0)
jbe@486 73 if channel then
jbe@486 74 if args.db_notify_handler(channel, payload, pid) then
jbe@486 75 process:kill():wait()
jbe@486 76 return return_error("Database event received")
jbe@486 77 end
jbe@486 78 end
jbe@486 79 end
jbe@486 80 if read_fds[process.stdout] then
jbe@486 81 local chunk, status = process.stdout:read_nb()
jbe@486 82 if not chunk or status == "eof" then
jbe@486 83 process.stdout:close()
jbe@486 84 read_fds[process.stdout] = nil
jbe@486 85 end
jbe@486 86 if chunk and chunk ~= "" then
jbe@486 87 stdout_chunks[#stdout_chunks+1] = chunk
jbe@486 88 end
jbe@486 89 end
jbe@486 90 if read_fds[process.stderr] then
jbe@486 91 local chunk, status = process.stderr:read_nb()
jbe@486 92 if not chunk or status == "eof" then
jbe@486 93 process.stderr:close()
jbe@486 94 read_fds[process.stderr] = nil
jbe@486 95 end
jbe@486 96 if chunk and args.stderr_line_handler then
jbe@486 97 while true do
jbe@486 98 local chunk1, chunk2 = string.match(chunk, "(.-)\n(.*)")
jbe@486 99 if not chunk1 then break end
jbe@486 100 stderr_chunks[#stderr_chunks+1] = chunk1
jbe@486 101 args.stderr_line_handler(table.concat(stderr_chunks))
jbe@486 102 stderr_chunks = {}
jbe@486 103 chunk = chunk2
jbe@486 104 end
jbe@486 105 if chunk ~= "" then
jbe@486 106 stderr_chunks[#stderr_chunks+1] = chunk
jbe@486 107 end
jbe@486 108 if status == "eof" then
jbe@486 109 local line = table.concat(stderr_chunks)
jbe@486 110 if #line > 0 then args.stderr_line_handler(line) end
jbe@486 111 end
jbe@486 112 end
jbe@486 113 end
jbe@486 114 write()
jbe@486 115 end
jbe@486 116
jbe@486 117 local status = process:wait()
jbe@486 118
jbe@486 119 if status < 0 then
jbe@486 120 if args.signal_handler then
jbe@486 121 args.signal_handler(-status)
jbe@486 122 end
jbe@486 123 return return_error("Command terminated by signal " .. -status)
jbe@486 124 elseif status > 0 then
jbe@486 125 if args.exit_handler then
jbe@486 126 args.exit_handler(status)
jbe@486 127 end
jbe@486 128 return return_error("Command returned exit code " .. status)
jbe@486 129 elseif args.stdout_result_handler then
jbe@486 130 args.stdout_result_handler(table.concat(stdout_chunks), true)
jbe@486 131 return true
jbe@486 132 else
jbe@486 133 return table.concat(stdout_chunks)
jbe@486 134 end
jbe@486 135
jbe@486 136 end

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