From 201aa20c5af6cb0095c60359560eb9a3ee3ae248 Mon Sep 17 00:00:00 2001
From: XeonSquared <redtailedairways@gmail.com>
Date: Mon, 16 Mar 2020 17:30:22 +1100
Subject: [PATCH] added the plan9k buffer library because it's cleaner than the
 old io library

---
 module/buffer.lua   | 429 ++++++++++++++++++++++++++++++++++++++++++++
 module/fs.lua       |  27 +--
 module/init.lua     |   3 +-
 module/io.lua       |  39 ++++
 module/loadfile.lua |   4 +-
 module/vt-task.lua  |   2 +-
 service/getty.lua   |   2 +-
 7 files changed, 477 insertions(+), 29 deletions(-)
 create mode 100644 module/buffer.lua
 create mode 100644 module/io.lua

diff --git a/module/buffer.lua b/module/buffer.lua
new file mode 100644
index 0000000..34d27a1
--- /dev/null
+++ b/module/buffer.lua
@@ -0,0 +1,429 @@
+-- shamelessly stolen from plan9k
+
+buffer = {}
+
+function buffer.new(mode, stream)
+ local result = {
+  mode = {},
+  stream = stream,
+  bufferRead = "",
+  bufferWrite = "",
+  bufferSize = math.max(512, math.min(8 * 1024, computer.freeMemory() / 8)),
+  bufferMode = "full",
+  readTimeout = math.huge
+ }
+ mode = mode or "r"
+ for i = 1, unicode.len(mode) do
+  result.mode[unicode.sub(mode, i, i)] = true
+ end
+ local metatable = {
+  __index = buffer,
+  __metatable = "file"
+ }
+ return setmetatable(result, metatable)
+end
+
+
+local function badFileDescriptor()
+ return nil, "bad file descriptor"
+end
+
+function buffer:close()
+ if self.mode.w or self.mode.a then
+  self:flush()
+ end
+ self.closed = true
+ return self.stream:close()
+end
+
+function buffer:flush()
+ local result, reason = self.stream:write(self.bufferWrite)
+ if result then
+  self.bufferWrite = ""
+ else
+  if reason then
+   return nil, reason
+  else
+   return nil, "bad file descriptor"
+  end
+ end
+
+ return self
+end
+
+function buffer:lines(...)
+ local args = table.pack(...)
+ return function()
+  local result = table.pack(self:read(table.unpack(args, 1, args.n)))
+  if not result[1] and result[2] then
+   error(result[2])
+  end
+  return table.unpack(result, 1, result.n)
+ end
+end
+
+function buffer:read(...)
+ local timeout = computer.uptime() + self.readTimeout
+
+ local function readChunk()
+  if computer.uptime() > timeout then
+   error("timeout")
+  end
+  local result, reason = self.stream:read(self.bufferSize)
+  if result then
+   self.bufferRead = self.bufferRead .. result
+   return self
+  else -- error or eof
+   return nil, reason
+  end
+ end
+
+ local function readBytesOrChars(n)
+  n = math.max(n, 0)
+  local len, sub
+  if self.mode.b then
+   len = rawlen
+   sub = string.sub
+  else
+   len = unicode.len
+   sub = unicode.sub
+  end
+  local buffer = ""
+  repeat
+   if len(self.bufferRead) == 0 then
+    local result, reason = readChunk()
+    if not result then
+     if reason then
+      return nil, reason
+     else -- eof
+      return #buffer > 0 and buffer or nil
+     end
+    end
+   end
+   local left = n - len(buffer)
+   buffer = buffer .. sub(self.bufferRead, 1, left)
+   self.bufferRead = sub(self.bufferRead, left + 1)
+  until len(buffer) == n
+  
+  --kernel.io.println("buffer read: "..tostring(buffer))
+  return buffer
+ end
+
+ local function readNumber()
+  local len, sub
+  if self.mode.b then
+   len = rawlen
+   sub = string.sub
+  else
+   len = unicode.len
+   sub = unicode.sub
+  end
+  local buffer = ""
+  local first = true
+  local decimal = false
+  local last = false
+  local hex = false
+  local pat = "^[0-9]+"
+  local minbuf = 3 -- "+0x" (sign + hexadecimal tag)
+  -- this function is used to read trailing numbers (1e2, 0x1p2, etc)
+  local function readnum(checksign)
+   local _buffer = ""
+   local sign = ""
+   while true do
+    if len(self.bufferRead) == 0 then
+     local result, reason = readChunk()
+     if not result then
+      if reason then
+       return nil, reason
+      else -- eof
+       return #_buffer > 0 and (sign .. _buffer) or nil
+      end
+     end
+    end
+    if checksign then
+     local _sign = sub(self.bufferRead, 1, 1)
+     if _sign == "+" or _sign == "-" then
+      -- "eat" the sign (Rio Lua behaviour)
+      sign = sub(self.bufferRead, 1, 1)
+      self.bufferRead = sub(self.bufferRead, 2)
+     end
+     checksign = false
+    else
+     local x,y = string.find(self.bufferRead, pat)
+     if not x then
+      break
+     else
+      _buffer = _buffer .. sub(self.bufferRead, 1, y)
+      self.bufferRead = sub(self.bufferRead, y + 1)
+     end
+    end
+   end
+   return #_buffer > 0 and (sign .. _buffer) or nil
+  end
+  while true do
+   if len(self.bufferRead) == 0 or len(self.bufferRead) < minbuf then
+    local result, reason = readChunk()
+    if not result then
+     if reason then
+      return nil, reason
+     else -- eof
+      return #buffer > 0 and tonumber(buffer) or nil
+     end
+    end
+   end
+   -- these ifs are here so we run the buffer check above
+   if first then
+    local sign = sub(self.bufferRead, 1, 1)
+    if sign == "+" or sign == "-" then
+     -- "eat" the sign (Rio Lua behaviour)
+     buffer = buffer .. sub(self.bufferRead, 1, 1)
+     self.bufferRead = sub(self.bufferRead, 2)
+    end
+    local hextag = sub(self.bufferRead, 1, 2)
+    if hextag == "0x" or hextag == "0X" then
+     pat = "^[0-9A-Fa-f]+"
+     -- "eat" the 0x, see https://gist.github.com/SoniEx2/570a363d81b743353151
+     buffer = buffer .. sub(self.bufferRead, 1, 2)
+     self.bufferRead = sub(self.bufferRead, 3)
+     hex = true
+    end
+    minbuf = 0
+    first = false
+   elseif decimal then
+    local sep = sub(self.bufferRead, 1, 1)
+    if sep == "." then
+     buffer = buffer .. sep
+     self.bufferRead = sub(self.bufferRead, 2)
+     local temp = readnum(false) -- no sign
+     if temp then
+      buffer = buffer .. temp
+     end
+    end
+    if not tonumber(buffer) then break end
+    decimal = false
+    last = true
+    minbuf = 1
+   elseif last then
+    local tag = sub(self.bufferRead, 1, 1)
+    if hex and (tag == "p" or tag == "P") then
+     local temp = sub(self.bufferRead, 1, 1)
+     self.bufferRead = sub(self.bufferRead, 2)
+     local temp2 = readnum(true) -- this eats the next sign if any
+     if temp2 then
+      buffer = buffer .. temp .. temp2
+     end
+    elseif tag == "e" or tag == "E" then
+     local temp = sub(self.bufferRead, 1, 1)
+     self.bufferRead = sub(self.bufferRead, 2)
+     local temp2 = readnum(true) -- this eats the next sign if any
+     if temp2 then
+      buffer = buffer .. temp .. temp2
+     end
+    end
+    break
+   else
+    local x,y = string.find(self.bufferRead, pat)
+    if not x then
+     minbuf = 1
+     decimal = true
+    else
+     buffer = buffer .. sub(self.bufferRead, 1, y)
+     self.bufferRead = sub(self.bufferRead, y + 1)
+    end
+   end
+  end
+  return tonumber(buffer)
+ end
+
+ local function readLine(chop)
+  local start = 1
+  while true do
+   local l = self.bufferRead:find("\n", start, true)
+   if l then
+    local result = self.bufferRead:sub(1, l + (chop and -1 or 0))
+    self.bufferRead = self.bufferRead:sub(l + 1)
+    return result
+   else
+    start = #self.bufferRead
+    local result, reason = readChunk()
+    if not result then
+     if reason then
+      return nil, reason
+     else -- eof
+      local result = #self.bufferRead > 0 and self.bufferRead or nil
+      self.bufferRead = ""
+      return result
+     end
+    end
+   end
+  end
+ end
+
+ local function readAll()
+  repeat
+   local result, reason = readChunk()
+   if not result and reason then
+    return nil, reason
+   end
+  until not result -- eof
+  local result = self.bufferRead
+  self.bufferRead = ""
+  return result
+ end
+
+ local function read(n, format)
+  if type(format) == "number" then
+   return readBytesOrChars(format)
+  else
+   if type(format) ~= "string" or unicode.sub(format, 1, 1) ~= "*" then
+    error("bad argument #" .. n .. " (invalid option)")
+   end
+   format = unicode.sub(format, 2, 2)
+   if format == "n" then
+    return readNumber()
+   elseif format == "l" then
+    return readLine(true)
+   elseif format == "L" then
+    return readLine(false)
+   elseif format == "a" then
+    return readAll()
+   else
+    error("bad argument #" .. n .. " (invalid format)")
+   end
+  end
+ end
+
+ if self.mode.w or self.mode.a then
+  self:flush()
+ end
+
+ local results = {}
+ local formats = table.pack(...)
+ if formats.n == 0 then
+  return readLine(true)
+ end
+ for i = 1, formats.n do
+  local result, reason = read(i, formats[i])
+  if result then
+   results[i] = result
+  elseif reason then
+   return nil, reason
+  end
+ end
+ return table.unpack(results, 1, formats.n)
+end
+
+function buffer:seek(whence, offset)
+ whence = tostring(whence or "cur")
+ assert(whence == "set" or whence == "cur" or whence == "end",
+  "bad argument #1 (set, cur or end expected, got " .. whence .. ")")
+ offset = offset or 0
+ checkArg(2, offset, "number")
+ assert(math.floor(offset) == offset, "bad argument #2 (not an integer)")
+
+ if self.mode.w or self.mode.a then
+  self:flush()
+ elseif whence == "cur" then
+  offset = offset - #self.bufferRead
+ end
+ local result, reason = self.stream:seek(whence, offset)
+ if result then
+  self.bufferRead = ""
+  return result
+ else
+  return nil, reason
+ end
+end
+
+function buffer:setvbuf(mode, size)
+ mode = mode or self.bufferMode
+ size = size or self.bufferSize
+
+ assert(mode == "no" or mode == "full" or mode == "line",
+  "bad argument #1 (no, full or line expected, got " .. tostring(mode) .. ")")
+ assert(mode == "no" or type(size) == "number",
+  "bad argument #2 (number expected, got " .. type(size) .. ")")
+
+ self.bufferMode = mode
+ self.bufferSize = size
+
+ return self.bufferMode, self.bufferSize
+end
+
+function buffer:getTimeout()
+ return self.readTimeout
+end
+
+function buffer:setTimeout(value)
+ self.readTimeout = tonumber(value)
+end
+
+function buffer:write(...)
+ if self.closed then
+  return nil, "bad file descriptor"
+ end
+ local args = table.pack(...)
+ for i = 1, args.n do
+  if type(args[i]) == "number" then
+   args[i] = tostring(args[i])
+  end
+  checkArg(i, args[i], "string")
+ end
+
+ for i = 1, args.n do
+  local arg = args[i]
+  local result, reason
+
+  if self.bufferMode == "full" then
+   if self.bufferSize - #self.bufferWrite < #arg then
+    result, reason = self:flush()
+    if not result then
+     return nil, reason
+    end
+   end
+   if #arg > self.bufferSize then
+    result, reason = self.stream:write(arg)
+   else
+    self.bufferWrite = self.bufferWrite .. arg
+    result = self
+   end
+
+  elseif self.bufferMode == "line" then
+   local l
+   repeat
+    local idx = arg:find("\n", (l or 0) + 1, true)
+    if idx then
+     l = idx
+    end
+   until not idx
+   if l or #arg > self.bufferSize then
+    result, reason = self:flush()
+    if not result then
+     return nil, reason
+    end
+   end
+   if l then
+    result, reason = self.stream:write(arg:sub(1, l))
+    if not result then
+     return nil, reason
+    end
+    arg = arg:sub(l + 1)
+   end
+   if #arg > self.bufferSize then
+    result, reason = self.stream:write(arg)
+   else
+    self.bufferWrite = self.bufferWrite .. arg
+    result = self
+   end
+
+  else -- self.bufferMode == "no"
+   result, reason = self.stream:write(arg)
+  end
+
+  if not result then
+   return nil, reason
+  end
+ end
+
+ return self
+end
diff --git a/module/fs.lua b/module/fs.lua
index 197cd60..b044a57 100644
--- a/module/fs.lua
+++ b/module/fs.lua
@@ -32,37 +32,16 @@ for k,v in pairs({"makeDirectory","exists","isDirectory","list","lastModified","
 end
 
 local function fread(self,length)
- if length == "*a" then
-  length = math.huge
- end
- if type(length) == "number" then
-  local rstr, lstr = "", ""
-  repeat
-   lstr = fsmounts[self.fs].read(self.fid,math.min(2^16,length-rstr:len())) or ""
-   rstr = rstr .. lstr
-  until rstr:len() == length or lstr == ""
-  return rstr
- elseif type(length) == "string" then
-  local buf = ""
-  if length == "*l" then
-   length = "\n"
-  end
-  repeat
-   local rb = fsmounts[self.fs].read(self.fid,1) or ""
-   buf = buf .. rb
-  until buf:match(length) or rb == ""
-  return buf:match("(.*)"..length)
- end
  return fsmounts[self.fs].read(self.fid,length)
 end
 local function fwrite(self,data)
- fsmounts[self.fs].write(self.fid,data)
+ return fsmounts[self.fs].write(self.fid,data)
 end
 local function fseek(self,dist)
- fsmounts[self.fs].seek(self.fid,dist)
+ return fsmounts[self.fs].seek(self.fid,dist)
 end
 local function fclose(self)
- fsmounts[self.fs].close(self.fid)
+ return fsmounts[self.fs].close(self.fid)
 end
 
 function fs.open(path,mode) -- opens file *path* with mode *mode*
diff --git a/module/init.lua b/module/init.lua
index 3412bef..9631452 100644
--- a/module/init.lua
+++ b/module/init.lua
@@ -1,8 +1,9 @@
 --#include "module/syslog.lua"
 --#include "module/sched.lua"
+--#include "module/buffer.lua"
 --#include "module/osutil.lua"
 --#include "module/fs.lua"
---#include "module/newio.lua"
+--#include "module/io.lua"
 --#include "module/devfs.lua"
 --#include "module/devfs/syslog.lua"
 --#include "module/vt-task.lua"
diff --git a/module/io.lua b/module/io.lua
new file mode 100644
index 0000000..b3401f0
--- /dev/null
+++ b/module/io.lua
@@ -0,0 +1,39 @@
+io = {}
+
+function io.open(path,mode)
+ local f,e = fs.open(path, mode)
+ if not f then return false, e end
+ return buffer.new(mode,f)
+end
+
+function io.input(fd)
+ if type(fd) == "string" then
+  fd=io.open(fd,"rb")
+ end
+ if fd then
+  os.setenv("STDIN",fd)
+ end
+ return os.getenv("STDIN")
+end
+function io.output(fd)
+ if type(fd) == "string" then
+  fd=io.open(fd,"wb")
+ end
+ if fd then
+  os.setenv("STDOUT",fd)
+ end
+ return os.getenv("STDOUT")
+end
+
+function io.read(...)
+ return io.input():read()
+end
+function io.write(...)
+ io.output():write(...)
+end
+
+function print(...)
+ for k,v in ipairs({...}) do
+  io.write(tostring(v).."\n")
+ end
+end
diff --git a/module/loadfile.lua b/module/loadfile.lua
index 4e305e3..cb5acc1 100644
--- a/module/loadfile.lua
+++ b/module/loadfile.lua
@@ -1,5 +1,5 @@
 function loadfile(p) -- reads file *p* and returns a function if possible
- local f = fs.open(p,"rb")
+ local f = io.open(p,"rb")
  local c = f:read("*a")
  f:close()
  return load(c,p,"t")
@@ -9,7 +9,7 @@ function runfile(p,...) -- runs file *p* with arbitrary arguments in the current
 end
 function os.spawnfile(p,n,...) -- spawns a new process from file *p* with name *n*, with arguments following *n*.
  local tA = {...}
- return os.spawn(function() computer.pushSignal("process_finished", os.pid(), pcall(loadfile(p), table.unpack(tA))) end,n or p)
+ return os.spawn(function() local res={pcall(loadfile(p), table.unpack(tA))} computer.pushSignal("process_finished", os.pid(), table.unpack(res)) dprint(table.concat(res)) end,n or p)
 end
 _G.libs = {computer=computer,component=component}
 function require(f) -- searches for a library with name *f* and returns what the library returns, if possible
diff --git a/module/vt-task.lua b/module/vt-task.lua
index d465c1c..6f61c5c 100644
--- a/module/vt-task.lua
+++ b/module/vt-task.lua
@@ -31,7 +31,7 @@ function vtemu(gpua,scra) -- creates a process to handle the GPU and screen addr
    coroutine.yield()
   end
   local n = buf:find("\n")
-  r, buf = buf:sub(1,n-1), buf:sub(n+1)
+  r, buf = buf:sub(1,n), buf:sub(n+1)
   return r
  end
  return bread, write, function() io.write("\27[2J\27[H") end
diff --git a/service/getty.lua b/service/getty.lua
index 5a4325c..91c9ce4 100644
--- a/service/getty.lua
+++ b/service/getty.lua
@@ -32,7 +32,7 @@ end
 
 local function spawnShell(fin,fout)
  io.input(fin)
- io.output(fout)
+ io.output(fout):setvbuf("no")
  print(_OSVERSION.." - "..tostring(math.floor(computer.totalMemory()/1024)).."K RAM")
  return os.spawnfile("/boot/exec/shell.lua")
 end