AP_Scripting: script switching system

Co-authored-by:Henry Wurzburg (hwurzburg@yahoo.com)

libraries/AP_Scripting/AP_Scripting.cpp

@@ -317,6 +317,12 @@ bool AP_Scripting::arming_checks(size_t buflen, char *buffer) const
     return true;
 }
 
+void AP_Scripting::scripting_restart()
+{
+    _stop = true;
+    _restart = true;
+}
+
 AP_Scripting *AP_Scripting::_singleton = nullptr;
 
 namespace AP {

libraries/AP_Scripting/AP_Scripting.h

@@ -50,6 +50,8 @@ public:
     void handle_mission_command(const class AP_Mission::Mission_Command& cmd);
 
     bool arming_checks(size_t buflen, char *buffer) const;
+    
+    void scripting_restart(void);
 
    // User parameters for inputs into scripts 
    AP_Float _user[6];

libraries/AP_Scripting/applets/script_controller.lua

@@ -0,0 +1,153 @@
+--[[
+   a script to select other lua scripts using an auxillary switch
+--]]
+
+local THIS_SCRIPT = "script_controller.lua"
+
+--[[
+   copy file src to dest, return true on success
+--]]
+function file_copy(src, dest)
+   local block_size = 256
+   local file1 = io.open(src, "rb")
+   if not file1 then
+      return false
+   end
+   local file2 = io.open(dest, "wb")
+   if not file2 then
+      file1:close()
+      return false
+   end
+   while true do
+      local block = file1:read(block_size)
+      if not block then
+         break
+      end
+      file2:write(block)
+   end
+   local ret = false
+   if file1:seek("end") == file2:seek("end") then
+      ret = true
+   end
+   file1:close()
+   file2:close()
+   return ret
+end
+
+--[[
+   compare two files, return true if they are the same
+--]]
+function file_compare(filename1, filename2)
+   local block_size = 256
+   local file1 = io.open(filename1, "rb")
+   if not file1 then
+      return false
+   end
+   local file2 = io.open(filename2, "rb")
+   if not file2 then
+      file1:close()
+      return false
+   end
+   local ret = true
+   while true do
+      local block1 = file1:read(block_size)
+      local block2 = file2:read(block_size)
+      if block1 ~= block2 then
+         ret = false
+         break
+      end
+      if not block1 then
+         break
+      end
+   end
+   file1:close()
+   file2:close()
+   return ret
+end
+
+--[[
+   get the path to the scripts directory. This will be scripts/ on SITL
+   and APM/scripts on a ChibiOS board
+--]]
+function get_scripts_dir()
+   local dlist1 = dirlist("APM/scripts")
+   if dlist1 and #dlist1 > 0 then
+      return "APM/scripts"
+   end
+   -- otherwise assume scripts/
+   return "scripts"
+end
+
+function file_exists(fname)
+   local f = io.open(fname,"rb")
+   if not f then
+      return false
+   end
+   f:close()
+   return true
+end
+
+--[[
+   remove any lua scripts in the scripts directory that are not in the given subdir
+   returns true if any files were removed
+--]]
+function remove_scripts(subdir)
+   local sdir = get_scripts_dir()
+   local dlist = dirlist(sdir)
+   if not dlist then
+      return false
+   end
+   local ret = false
+   for k,v in ipairs(dlist) do
+      local suffix = v:sub(-4)
+      if suffix == ".lua" and v ~= THIS_SCRIPT then
+         if not file_exists(subdir .. "/" .. v) then
+            ret = true
+            remove(sdir .. "/" .. v)
+         end
+      end
+   end
+   return ret
+end
+
+--[[
+   copy scripts from a subdir to the main scripts directory
+   return true if any changes were made
+--]]
+function copy_scripts(subdir)
+   local dlist = dirlist(subdir)
+   if not dlist then
+      return false
+   end
+   local ret = false
+   local sdir = get_scripts_dir()
+   for k, v in ipairs(dlist) do
+      local suffix = v:sub(-4)
+      gcs:send_text(0, string.format("checking %s", v))
+      if suffix == ".lua" and v ~= THIS_SCRIPT then
+         local src = subdir .. "/" .. v
+         local dest = sdir .. "/" .. v
+         if not file_compare(src, dest) then
+            ret = true
+            gcs:send_text(0, string.format("copying %s -> %s", src, dest))
+            file_copy(src, dest)
+         else
+            gcs:send_text(0, string.format("same %s -> %s", src, dest))
+         end
+      end
+   end
+   return ret
+end
+
+--[[
+   activate a scripting subdirectory
+--]]
+function activate_subdir(n)
+   gcs:send_text(0, string.format("Activating %s", n))
+   -- step1, remove lua files from scripts/ that are not in the givem subdirectory
+   local subdir = get_scripts_dir() .. "/" .. n
+   local changes_made = remove_scripts(subdir)
+   changes_made = changes_made or copy_scripts(subdir)
+end
+
+activate_subdir(1)

libraries/AP_Scripting/docs/docs.lua

@@ -2361,3 +2361,19 @@ function follow:get_last_update_ms() end
 -- desc
 ---@return boolean
 function follow:have_target() end
+
+-- desc
+---@class scripting
+scripting = {}
+
+-- desc
+function scripting:scripting_restart() end
+
+-- desc
+--@param directoryname
+--@return list of filenames
+function dirlist(directoryname) end
+
+--desc
+--@param filename
+function remove(filename) end

libraries/AP_Scripting/generator/description/bindings.desc

@@ -356,6 +356,9 @@ userdata Parameter method set_and_save boolean float'skip_check
 userdata Parameter method configured boolean
 userdata Parameter method set_default boolean float'skip_check
 
+include AP_Scripting/AP_Scripting.h
+singleton AP_Scripting rename scripting
+singleton AP_Scripting method scripting_restart void
 
 include AP_Mission/AP_Mission.h
 singleton AP_Mission rename mission
@@ -635,3 +638,5 @@ userdata uint32_t manual_operator __tostring uint32_t___tostring
 userdata uint32_t manual toint uint32_t_toint 0
 userdata uint32_t manual tofloat uint32_t_tofloat 0
 
+global manual dirlist lua_dirlist 1
+global manual remove lua_removefile 1

libraries/AP_Scripting/lua_bindings.cpp

@@ -1,6 +1,7 @@
 #include <AP_Common/AP_Common.h>
 #include <AP_HAL/HAL.h>
 #include <AP_Logger/AP_Logger.h>
+#include <AP_Filesystem/AP_Filesystem.h>
 
 #include "lua_bindings.h"
 
@@ -494,3 +495,40 @@ int lua_get_CAN_device2(lua_State *L) {
     return 1;
 }
 #endif // HAL_MAX_CAN_PROTOCOL_DRIVERS
+
+/*
+  directory listing, return table of files in a directory
+ */
+int lua_dirlist(lua_State *L) {
+    struct dirent *entry;
+    int i;
+    const char *path = luaL_checkstring(L, 1);
+    
+    /* open directory */
+    auto dir = AP::FS().opendir(path);
+    if (dir == nullptr) {  /* error opening the directory? */
+        lua_pushnil(L);  /* return nil and ... */
+        lua_pushstring(L, strerror(errno));  /* error message */
+        return 2;  /* number of results */
+    }
+    
+    /* create result table */
+    lua_newtable(L);
+    i = 1;
+    while ((entry = AP::FS().readdir(dir)) != nullptr) {
+        lua_pushnumber(L, i++);  /* push key */
+        lua_pushstring(L, entry->d_name);  /* push value */
+        lua_settable(L, -3);
+    }
+    
+    AP::FS().closedir(dir);
+    return 1;  /* table is already on top */
+}
+
+/*
+  remove a file
+ */
+int lua_removefile(lua_State *L) {
+  const char *filename = luaL_checkstring(L, 1);
+  return luaL_fileresult(L, remove(filename) == 0, filename);
+}

libraries/AP_Scripting/lua_bindings.h

@@ -10,3 +10,5 @@ int lua_get_i2c_device(lua_State *L);
 int AP_HAL__I2CDevice_read_registers(lua_State *L);
 int lua_get_CAN_device(lua_State *L);
 int lua_get_CAN_device2(lua_State *L);
+int lua_dirlist(lua_State *L);
+int lua_removefile(lua_State *L);