virtual terminal support with vtansi and getty, for machines with VRAM available

lib/shell.lua

@@ -21,24 +21,29 @@ end
 function shell.interactive()
  local shenv = setmetatable({}, {__index=shindex})
  local run = true
+ os.setenv("PATH",{"/boot/exec","/pkg/exec"})
  function shenv.quit()
   run = false
  end
  while run do
   io.write(string.format("\27[32m%s:%s>\27[0m ",os.getenv("HOSTNAME") or "localhost",(os.getenv("PWD") or _VERSION)))
-  local input = io.read()
-  if input:sub(1,1) == "=" then
-   input = "return "..input:sub(2)
-  end
-  local f, r = load(input, "shell", "t", shenv)
-  if not f then
-   print("\27[31m"..r)
+  local w,input = pcall(io.read)
+  if not w then
+   print("\27[31m^C")
   else
-   local rt = {pcall(f)}
-   local rs = table.remove(rt,1)
-   if not rs then io.write("\27[31m") end
-   for k,v in pairs(rt) do
-    print(formatValue(v))
+   if input:sub(1,1) == "=" then
+    input = "return "..input:sub(2)
+   end
+   local f, r = load(input, "shell", "t", shenv)
+   if not f then
+    print("\27[31m"..r)
+   else
+    local rt = {pcall(f)}
+    local rs = table.remove(rt,1)
+    if not rs then io.write("\27[31m") end
+    for k,v in pairs(rt) do
+     print(formatValue(v))
+    end
    end
   end
  end

lib/shutil.lua

@@ -119,9 +119,49 @@ function shutil.free() -- Displays used and free memory.
  print(string.format("%5s %5s %5s",wrapUnits(computer.totalMemory()),wrapUnits(computer.totalMemory()-computer.freeMemory()),wrapUnits(computer.freeMemory())))
 end
 
+local function pread(self,len)
+ syslog(tostring(self))
+ syslog(tostring(len))
+ io.input(self.input)
+ local b = io.read(len)
+ io.input(self)
+ if b:match("\3") then
+  error("terminated")
+ end
+ return b
+end
+
+function shutil.which(name)
+ local fpath
+ for _,dir in ipairs(os.getenv("PATH")) do
+  fpath = fpath or fs.exists(string.format("%s/%s.lua",dir,name)) and string.format("%s/%s.lua",dir,name) or fs.exists(string.format("%s/%s",dir,name)) and string.format("%s/%s",dir,name)
+ end
+ return fpath
+end
+
 shutil.cd = os.chdir
 shutil.mkdir = fs.makeDirectory
 shutil.cp = fs.copy
 shutil.rm = fs.remove
 
-return shutil
+return setmetatable({}, {__index = function(t,k)
+ if shutil[k] then
+  return shutil[k]
+ end
+ local path = shutil.which(k)
+ if path then
+  local fn, e = loadfile(path)
+  if not fn then error(string.format("\n - %s",e)) end
+  return function()
+   local pid = os.spawn(fn,path)
+   local ret = {require("event").pull("process_finished",pid)}
+   if not ret[3] then
+    error(string.format("\n - %s",ret[4]))
+   end
+   for i = 1, 3 do
+    table.remove(ret,1)
+   end
+   return table.unpack(ret)
+  end
+ end
+end})

lib/vtansi.lua

@@ -1,4 +1,6 @@
 local vtansi = {}
+local keyboardIgnore = {}
+vtansi.activeBuffers = {}
 vtansi.sequences = {
  [28] = "\n", -- newline
  [200] = "\27[A", -- up
@@ -8,9 +10,26 @@ vtansi.sequences = {
  [201] = "\27[5~", -- page up
  [209] = "\27[6~" -- page down
 }
-function vtansi.vtemu(gpu) -- table -- function -- takes GPU component proxy *gpu* and returns a function to write to it in a manner like an ANSI terminal
+vtansi.keys = {}
+vtansi.keys[0x38] = "lalt"
+vtansi.keys[0xB8] = "ralt"
+function vtansi.saveToBuffer(gpu,idx)
+ gpu.bitblt(idx, nil, nil, nil, nil, 0)
+end
+function vtansi.loadFromBuffer(gpu,idx)
+ gpu.bitblt(0, nil, nil, nil, nil, idx)
+end
+function vtansi.switchToBuffer(gpu,idx)
+ -- copy screen to the active buffer
+ vtansi.saveToBuffer(gpu,vtansi.activeBuffers[gpu.address])
+ -- copy the new buffer to the screen
+ vtansi.loadFromBuffer(gpu,idx)
+ vtansi.activeBuffers[gpu.address] = idx
+end
+function vtansi.vtemu(gpu,bn) -- table number -- function -- takes GPU component proxy *gpu* and returns a function to write to it in a manner like an ANSI terminal, either allocating a new buffer or using *bn*.
  local colours = {0x0,0xFF0000,0x00FF00,0xFFFF00,0x0000FF,0xFF00FF,0x00B6FF,0xFFFFFF}
  local mx, my = gpu.maxResolution()
+ local buffer = nil
  local cx, cy = 1, 1
  local pc = " "
  local lc = ""
@@ -21,8 +40,19 @@ function vtansi.vtemu(gpu) -- table -- function -- takes GPU component proxy *gp
  local bg, fg = 0, 0xFFFFFF
 
  -- setup
- gpu.setResolution(mx,my)
- gpu.fill(1,1,mx,my," ")
+ if gpu.getActiveBuffer then
+  buffer = bn or gpu.allocateBuffer(mx,my)
+  vtansi.activeBuffers[gpu.address] = vtansi.activeBuffers[gpu.address] or buffer
+  local oldActiveBuffer = vtansi.activeBuffers[gpu.address]
+  gpu.setActiveBuffer(buffer)
+  gpu.setResolution(mx,my)
+  gpu.fill(1,1,mx,my," ")
+  gpu.setActiveBuffer(oldActiveBuffer)
+ else
+  gpu.setResolution(mx,my)
+  gpu.fill(1,1,mx,my," ")
+ end
+
  local function checkCursor()
   if cx > mx and lw then
    cx, cy = 1, cy+1
@@ -37,6 +67,13 @@ function vtansi.vtemu(gpu) -- table -- function -- takes GPU component proxy *gp
  end
 
  local function termwrite(s)
+  if buffer then
+   if vtansi.activeBuffers[gpu.address] == buffer then
+    gpu.setActiveBuffer(0)
+   else
+    gpu.setActiveBuffer(buffer)
+   end
+  end
   local wb = ""
   local lb, ec = nil, nil
   local function flushwb()
@@ -161,13 +198,14 @@ function vtansi.vtemu(gpu) -- table -- function -- takes GPU component proxy *gp
   return rs, lb, ec
  end
 
- return termwrite
+ return termwrite, buffer
 end
 
-function vtansi.vtsession(gpua,scra) -- string string -- table -- creates a process to handle the GPU and screen address combination *gpua*/*scra*. Returns read, write and "close" functions.
+function vtansi.vtsession(gpua,scra,bn) -- string string number -- function function function -- creates a process to handle the GPU and screen address combination *gpua*/*scra*, optionally using buffer number *bn* specifically. Returns read, write and "close" functions.
+ local modifiers = {}
  local gpu = component.proxy(gpua)
- gpu.bind(scra)
- local write = vtansi.vtemu(gpu)
+-- gpu.bind(scra)
+ local write, bn = vtansi.vtemu(gpu,bn)
  local kba = {}
  for k,v in ipairs(component.invoke(scra,"getKeyboards")) do
   kba[v]=true
@@ -176,19 +214,45 @@ function vtansi.vtsession(gpua,scra) -- string string -- table -- creates a proc
  os.spawn(function()
   while true do
    local ty,ka,ch,kc = coroutine.yield()
-   if ty == "key_down" and kba[ka] then
-    local outs
-    if ch > 0 then
-     outs = string.char(ch)
-    end
-    outs = vtansi.sequences[kc] or outs
-    if outs then
-     if echo then write(outs) end
-     buf=buf..outs
+   if kba[ka] and keyboardIgnore[ka] == bn then
+    keyboardIgnore[ka] = nil
+   end
+   if kba[ka] and vtansi.keys[kc] then
+    modifiers[vtansi.keys[kc]] = ty == "key_down"
+   end
+   if ty == "key_down" and kba[ka] and (bn == nil or vtansi.activeBuffers[gpua] == bn) then
+    if bn and ty == "key_down" and kba[ka] and ch == 46 and kc == 52 and (modifiers.lalt or modifiers.ralt) then
+     -- next buffer
+     local allBuffers = gpu.buffers()
+     for k,v in ipairs(allBuffers) do
+      if v == vtansi.activeBuffers[gpu.address] and allBuffers[k+1] and not keyboardIgnore[ka] then
+       keyboardIgnore[ka] = bn
+       vtansi.switchToBuffer(gpu,allBuffers[k+1])
+      end
+     end
+    elseif bn and ty == "key_down" and kba[ka] and ch == 44 and kc == 51 and (modifiers.lalt or modifiers.ralt) then
+     -- previous buffer
+     local allBuffers = gpu.buffers()
+     for k,v in ipairs(allBuffers) do
+      if v == vtansi.activeBuffers[gpu.address] and allBuffers[k-1] and not keyboardIgnore[ka] then
+       keyboardIgnore[ka] = bn
+       vtansi.switchToBuffer(gpu,allBuffers[k-1])
+      end
+     end
+    else
+     local outs
+     if ch > 0 then
+      outs = string.char(ch)
+     end
+     outs = vtansi.sequences[kc] or outs
+     if outs then
+      if echo then write(outs) end
+      buf=buf..outs
+     end
     end
    end
   end
- end,string.format("ttyd[%s:%s]",gpua:sub(1,8),scra:sub(1,8)))
+ end,string.format("ttyd[%s:%s/%i]",gpua:sub(1,8),scra:sub(1,8),tonumber(bn) or 0))
  local function bread(n)
   coroutine.yield()
   local r = buf

module/buffer.lua

@@ -307,6 +307,8 @@ function buffer:read(...)
      if #buffer > 0 and pos <= #buffer then
       buffer = buffer:sub(1, (#buffer - pos)) .. buffer:sub((#buffer - pos) + 2)
      end
+    elseif char == "\3" then -- ^C, error
+     error("terminated")
     elseif char == "\1" then -- ^A, go to start of line
      pos = buffer:len()+1
     elseif char == "\5" then -- ^E, go to end of line

module/fs.lua

@@ -54,7 +54,7 @@ function fs.open(path,mode) -- string string -- table -- Opens file *path* with
   if mode:find("r") then
    fobj.read = fread
   end
-  if mode:find("w") then
+  if mode:find("w") or mode:find("a") then
    fobj.write = fwrite
   end
   return fobj

service/getty.lua

@@ -37,20 +37,32 @@ local function spawnShell(fin,fout)
  io.input(fin)
  io.output(fout):setvbuf("no")
  print(_OSVERSION.." - "..tostring(math.floor(computer.totalMemory()/1024)).."K RAM")
- return os.spawn(function() local w,r = pcall(shell.interactive) if not w then syslog(r) end end, "shell: "..tostring(fin))
+ print((os.getenv("HOSTNAME") or "unknown") .. " on " .. fin)
+-- return os.spawn(function() local w,r = pcall(shell.interactive) if not w then syslog(r) end end, "shell: "..tostring(fin))
+ return os.spawn(shell.interactive, "shell: "..tostring(fin))
 end
 
 local function allocate()
  for k,v in pairs(gpus) do
-  dprint(k)
+  dprint("Setting up display "..k)
   local sA = nextScreen(v[2])
   if v[1] == false and sA then
-   local r,w = vtansi.vtsession(k,sA)
-   devfs.register("tty"..tostring(ttyn), function() return r,w,function() end end)
+   local terminals = 1
+   local gpu = component.proxy(k)
+   gpu.bind(sA)
+   if gpu.buffers then
+    gpu.freeAllBuffers()
+    local mw, mh = gpu.maxResolution()
+    terminals = math.floor(gpu.freeMemory() / (mw * mh))
+   end
+   for i = 1, terminals do
+    local r,w = vtansi.vtsession(k,sA)
+    devfs.register("tty"..tostring(ttyn), function() return r,w,function() end end)
+    pids["tty"..tostring(ttyn)] = {-1}
+    ttyn = ttyn + 1
+   end
    gpus[k][1] = true
    screens[sA][1] = true
-   pids["tty"..tostring(ttyn)] = {-1}
-   ttyn = ttyn + 1
   end
  end
 end
@@ -59,14 +71,15 @@ function start()
 basepid = os.spawn(function()
 scan()
 allocate()
-dprint("screens ready")
+dprint("Display setup complete.")
 while true do
  coroutine.yield()
  for k,v in pairs(pids) do
   if not os.taskInfo(v[1]) then
    dprint("Spawning new shell for "..k)
    pids[k][1] = spawnShell(v[2] or "/dev/"..k, v[3] or "/dev/"..k)
-   pids[k][2], pids[k][3] = pids[k][2] or io.input(), pids[k][3] or io.output()
+   pids[k][2], pids[k][3] = pids[k][2] or "/dev/"..k, pids[k][3] or "/dev/"..k
+   coroutine.yield()
   end
  end
 end