Lua add metadata and settings reading helper module

Adds example scripts for reading track metadata + dumping albumart
and rockbox settings

settings are now stored as a table of strings rather than a table of tables
as it saves ~15 kb of ram without adding much complexity

Change-Id: I611c312b2a60ab96e595e4710b17aedbd6c0689b

apps/plugins/lua/include_lua/rbsettings.lua

@@ -0,0 +1,164 @@
+--[[ Lua rb settings reader
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2019 William Wilgus
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+]]
+
+rb.settings = rb.settings or {}
+
+local var = {offset = 1, size = 2, type = 3, fields = 3}
+
+local function bytesLE_n(str)
+    str = str or ""
+    local tbyte={str:byte(1, -1)}
+    local bpos, num = 1, 0
+    for k = 1,#tbyte do -- (k = #t, 1, -1 for BE)
+        num = num + tbyte[k] * bpos
+        bpos = bpos * 256 --1<<8
+    end
+    return num
+end
+
+local function get_var_fields(s_var)
+    -- converts member string into table
+    -- var = {offset, size, "type"}
+    s_var = s_var or ""
+    local o, s, t = string.match(s_var, "(0x%x+),%s*(%d+),%s*(.+)")
+    local tvar = {o, s, t}
+
+    return #tvar == var.fields and tvar or nil
+end
+
+local function format_val(val, var_type)
+    local ret, num
+    if var_type == nil then
+        return nil
+    elseif var_type == "str" then
+        -- stop at first null byte, return nil if str doesn't exist
+        return val and string.match(val, "^%Z+") or nil
+    end
+
+    num = bytesLE_n(val)
+    if string.find(var_type, "^b") then
+        if(num <= 0) then
+            ret = false
+        else
+            ret = true
+        end
+    elseif string.find(var_type, "^u_[cil]") then
+        -- Lua integers are signed so we need to do a bit of extra processing
+        ret = (string.format("%u", num))
+    else
+        ret = num
+    end
+
+    return ret
+end
+
+local function dump_struct(t_settings, t_struct, n_elems, t_var)
+    --Internal function dumps structs
+    local tdata = {}
+
+    local function struct_get_elem(v, elem_offset)
+        local val, offset, tvar1
+        tvar1 = get_var_fields(v)
+        offset = t_var[var.offset] + tvar1[var.offset] + elem_offset
+        val = t_settings(offset, tvar1[var.size])
+        return format_val(val, tvar1[var.type])
+    end
+
+    if n_elems > 0 then
+        -- Array of structs, struct[elems];
+        local elemsize = (t_var[var.size] / n_elems)
+        for i = 0, n_elems - 1 do
+            tdata[i] = tdata[i] or {}
+            for k1, v1 in pairs(t_struct) do
+                tdata[i][k1] = struct_get_elem(v1, (elemsize * i))
+            end
+        end
+    else
+        -- single struct, struct;
+        for k1, v1 in pairs(t_struct) do
+            tdata[k1] = struct_get_elem(v1, 0)
+        end
+    end
+    return tdata
+end
+
+local function get_array_elems(var_type)
+    --extract the number of elements, returns 0 if not found
+    local elems = string.match(var_type,".*%[(%d+)%]")
+    return tonumber(elems) or 0
+end
+
+local function get_struct_name(var_type)
+    --extract the name of a struct, returns nil if not found
+    return string.match(var_type,"^s_([^%[%]%s]+)")
+end
+
+function rb.settings.read(s_settings, s_var, s_groupname)
+    local data, val
+    local tvar = get_var_fields(s_var)
+    if tvar == nil then return nil end
+
+    local elems = get_array_elems(tvar[var.type])
+    local structname = get_struct_name(tvar[var.type])
+
+    local tsettings = rb[s_settings]
+    if not tsettings then error(s_settings .. " does not exist") end
+
+    if structname and rb[s_groupname] then
+        return dump_struct(tsettings, rb[s_groupname][structname], elems, tvar)
+    end
+
+    local voffset, vsize, vtype = tvar[var.offset], tvar[var.size], tvar[var.type]
+    if elems > 0 then
+        -- Arrays of values, val[elems];
+        data = {}
+        local elemsize = (vsize / elems)
+
+        for i = 0, elems - 1 do
+            val = tsettings(voffset + (elemsize * i), elemsize)
+            data[i] = format_val(val, vtype)
+        end
+    else
+        -- Single value, val;
+        if vtype == "ptr_char" then -- (**char)
+            vtype = "str"
+            val = tsettings(voffset, vsize, nil, true)
+        else
+            val = tsettings(voffset, vsize)
+        end
+        data = format_val(val, vtype)
+    end
+    return data
+end
+
+function rb.settings.dump(s_settings, s_groupname, s_structname, t_output)
+    t_output = t_output or {}
+    local tgroup = rb[s_groupname]
+    s_structname = s_structname or s_settings
+    for k, v in pairs(tgroup[s_structname]) do
+        t_output[k] = rb.settings.read(s_settings, v, s_groupname)
+    end
+    return t_output
+end
+
+return true

apps/plugins/lua/lua.make

@@ -19,7 +19,7 @@ LUA_INCLUDEDIR := $(LUA_SRCDIR)/include_lua
 LUA_INCLUDELIST := $(addprefix $(LUA_BUILDDIR)/,audio.lua blit.lua color.lua draw.lua draw_floodfill.lua draw_poly.lua \
 						draw_num.lua draw_text.lua image.lua image_save.lua lcd.lua math_ex.lua \
 						print.lua timer.lua playlist.lua pcm.lua sound.lua \
-						rbcompat.lua poly_points.lua printtable.lua)
+						rbcompat.lua rbsettings.lua poly_points.lua printtable.lua)
 
 
 ifndef APP_TYPE

apps/plugins/lua/rocklib.c

@@ -640,8 +640,12 @@ RB_WRAP(strncasecmp)
     return 1;
 }
 
-static int mem_read_write(lua_State *L, uintptr_t address, size_t maxsize)
+static int mem_read_write(lua_State *L, uintptr_t address, size_t maxsize, bool isstr_p)
 {
+    if(isstr_p) /*pointer to string (**char)*/
+    {
+        lua_settop(L, 2); /* no writes allowed */
+    }
     intptr_t offset = (intptr_t) luaL_optnumber(L, 1, 0);
     size_t   size   = (size_t)   luaL_optnumber(L, 2, maxsize);
     size_t   written;
@@ -716,6 +720,11 @@ static int mem_read_write(lua_State *L, uintptr_t address, size_t maxsize)
         case  LUA_TNIL:
         case LUA_TNONE: /* reader */
         {
+            if(isstr_p && mem)
+            {
+                lua_pushstring (L, *(char**) mem);
+                return 1;
+            }
             luaL_Buffer b;
             luaL_buffinit(L, &b);
             while(size > 0)
@@ -746,32 +755,51 @@ RB_WRAP(global_status)
 {
     const uintptr_t address = (uintptr_t) rb->global_status;
     const size_t    maxsize = sizeof(struct system_status);
-    return mem_read_write(L, address, maxsize);
+    /*const bool      isstr_p = lua_toboolean(L, 4);*/
+    return mem_read_write(L, address, maxsize, false);
 }
 
 RB_WRAP(global_settings)
 {
     const uintptr_t address = (uintptr_t) rb->global_settings;
     const size_t    maxsize = sizeof(struct user_settings);
-    return mem_read_write(L, address, maxsize);
+    /*const bool      isstr_p = lua_toboolean(L, 4);*/
+    return mem_read_write(L, address, maxsize, false);
 }
 
 RB_WRAP(audio_next_track)
 {
-    lua_settop(L, 2); /* no writes allowed */
+
     const uintptr_t address = (uintptr_t) rb->audio_next_track();
     const size_t    maxsize = sizeof(struct mp3entry);
-    return mem_read_write(L, address, maxsize);
+    const bool      isstr_p = lua_toboolean(L, 4);
+    lua_settop(L, 2); /* no writes allowed */
+    return mem_read_write(L, address, maxsize, isstr_p);
 }
 
 RB_WRAP(audio_current_track)
 {
-    lua_settop(L, 2); /* no writes allowed */
+
     const uintptr_t address = (uintptr_t) rb->audio_current_track();
     const size_t    maxsize = sizeof(struct mp3entry);
-    return mem_read_write(L, address, maxsize);
+    const bool      isstr_p = lua_toboolean(L, 4);
+    lua_settop(L, 2); /* no writes allowed */
+    return mem_read_write(L, address, maxsize, isstr_p);
 }
 
+#if 0
+RB_WRAP(read_mem)
+{
+    lua_settop(L, 2); /* no writes allowed */
+    const uintptr_t address = lua_tonumber(L, 1);
+    const size_t    maxsize = luaL_optnumber(L, 2, strlen((char *)address));
+    luaL_argcheck(L, address > 0,  1, ERR_IDX_RANGE);
+    lua_pushnil(L);
+    lua_replace(L, -3);/* stk pos 1 is no longer offset it is starting address */
+    return mem_read_write(L, address, maxsize, false);
+}
+#endif
+
 RB_WRAP(restart_lua)
 {
     /*close lua state, open a new lua state, load script @ filename */

apps/plugins/lua/settings_helper.pl

@@ -293,7 +293,7 @@ sub Print_Variable {
             $type = sprintf('%s[%d]', $1, $arr);
         }
 
-        printf "\t%s = {0x%x, %d, \"%s\"},\n", $member, $offset, $size, $type;
+        printf "\t%s = \"0x%x, %d, %s\",\n", $member, $offset, $size, $type;
         return 1;
     }
     return 0;
@@ -303,7 +303,7 @@ if($header) #output sections to lua file [PASS 2]
 {
     print "-- Don't change this file!\n";
     printf "-- It is automatically generated %s\n", $svnrev;
-    print "-- member = {offset, size, \"type\"}\n\n";
+    print "-- member = \"offset, size, type\"\n\n";
 
     print "--";
     foreach my $key (sort(keys %replace_type_prefix)) {
@@ -337,6 +337,7 @@ if($header) #output sections to lua file [PASS 2]
             }
         }
     }
+    print "\nreturn false\n";
     #my ($user,$system,$cuser,$csystem) = times;
     #warn "Pass2 ".$user." ".$system." ".$cuser." ".$csystem."\n";
     exit;

apps/plugins/lua_scripts/dump_rbsettings.lua

@@ -0,0 +1,49 @@
+require("rbsettings")
+require("settings")
+rb.metadata = nil -- remove track metadata settings
+-------------------------------------------------------------------------------
+
+local function print_setting_table(t_tbl, s_sep)
+    s_sep = s_sep or ""
+    local str = ""
+    local function pfunct(t, sep, s, n) -- recursive print function
+        local vtype
+        for k, v in pairs(t) do
+            vtype = type(v)
+            if vtype == "table" then
+                local f = string.format("%s[%s]", n, k)
+                s = pfunct(v, sep, s, f)
+            elseif vtype ==  "boolean" then
+                v = v and "true" or "false"
+                s = string.format("%s%s[%s] = %s%s", s, n, k, v, sep)
+            elseif v then
+                s = string.format("%s%s[%s] = %s%s", s, n, k, v, sep)
+            end
+        end
+        return s
+    end
+    return pfunct(t_tbl, s_sep, str, "")
+end
+
+local filename = "/settings.txt"
+local file = io.open(filename, "w+") -- overwrite
+local t_settings
+
+if not file then
+    rb.splash(rb.HZ, "Error writing " .. filename)
+    return
+end
+
+t_settings = rb.settings.dump('global_settings', "system")
+file:write("global_settings:\n")
+file:write(print_setting_table(t_settings, "\n"))
+file:write("\n\n")
+
+t_settings = rb.settings.dump('global_status', "system")
+file:write("global_status:\n")
+file:write(print_setting_table(t_settings, "\n"))
+file:write("\n\n")
+
+file:close()
+
+rb.splash(100, "rb settings dumped: " .. filename)

apps/plugins/lua_scripts/track_metadata.lua

@@ -0,0 +1,90 @@
+require("rbsettings")
+require("settings") --settings.lua
+rb.system = nil -- remove system settings
+-------------------------------------------------------------------------------
+local track_data = rb.metadata.mp3_entry
+local cur_trk = "audio_current_track"
+-------------------------------------------------------------------------------
+local trackname  = rb.settings.read(cur_trk, track_data.title) or
+                   rb.settings.read(cur_trk, track_data.path)
+if not trackname or trackname == "" then
+    os.exit(1, "No track loaded")
+else
+    rb.splash(100, trackname)
+end
+-------------------------------------------------------------------------------
+local function dump_albumart(fileout)
+    local t_albumart = rb.settings.read(cur_trk, track_data.albumart, "metadata")
+    local t_aaext = {".bmp",".png", ".jpg"}
+    local path = rb.settings.read(cur_trk, track_data.path)
+    if t_albumart.pos > 0 and t_albumart.size > 0 and t_albumart.type > 0 then
+
+        if t_aaext[t_albumart.type] then
+            local filename = "/" .. fileout .. t_aaext[t_albumart.type]
+            local aa = io.open(filename, "w+") -- overwrite
+            if not aa then
+                rb.splash(rb.HZ, "Error writing " .. filename)
+                return
+            end
+
+            local track = io.open(path, "r")
+            if not track then
+                rb.splash(rb.HZ, "Error opening " .. path)
+                return
+            end
+            track:seek("set", t_albumart.pos )
+            for i = 0, t_albumart.size, 32 do
+                aa:write(track:read(32))
+            end
+            rb.splash(rb.HZ, "Saved: " .. filename)
+            track:close()
+            aa:close()
+        else
+
+        end
+    end
+end
+
+local function print_setting_table(t_tbl, s_sep)
+    s_sep = s_sep or ""
+    local str = ""
+    local function pfunct(t, sep, s, n) -- recursive print function
+        local vtype
+        for k, v in pairs(t) do
+            vtype = type(v)
+            if vtype == "table" then
+                local f = string.format("%s[%s]", n, k)
+                s = pfunct(v, sep, s, f)
+            elseif vtype ==  "boolean" then
+                v = v and "true" or "false"
+                s = string.format("%s%s[%s] = %s%s", s, n, k, v, sep)
+            elseif v then
+                s = string.format("%s%s[%s] = %s%s", s, n, k, v, sep)
+            end
+        end
+        return s
+    end
+    return pfunct(t_tbl, s_sep, str, "")
+end
+
+local filename = "/metadata.txt"
+local file = io.open(filename, "w+") -- overwrite
+local t_settings
+
+if not file then
+    rb.splash(rb.HZ, "Error writing " .. filename)
+    return
+end
+
+---[[
+t_settings = rb.settings.dump(cur_trk, "metadata", "mp3_entry")
+file:write(trackname .. ":\n")
+file:write(print_setting_table(t_settings, "\n"))
+file:write("\n\n")
+file:close()
+
+rb.splash(100, "metadata dumped: " .. filename)
+
+if rb.settings.read(cur_trk, track_data.has_embedded_albumart) then
+    dump_albumart("/albumart")
+end