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-rw-r--r--serialize_lib/serialize.lua269
1 files changed, 0 insertions, 269 deletions
diff --git a/serialize_lib/serialize.lua b/serialize_lib/serialize.lua
deleted file mode 100644
index 12a26c4..0000000
--- a/serialize_lib/serialize.lua
+++ /dev/null
@@ -1,269 +0,0 @@
--- serialize.lua
--- Lua-conformant library file that has no minetest dependencies
--- Contains the serialization and deserialization routines
-
---[[
-
-Structure of entry:
-[keytype][key]:[valuetype][val]
-Types:
- B - bool
- -> 0=false, 1=true
- S - string
- -> see below
- N - number
- -> thing compatible with tonumber()
-Table:
-[keytype][key]:T
-... content is nested in table until the matching
-E
-
-example:
-LUA_SER v=1 {
-Skey:Svalue key = "value",
-N1:Seins [1] = "eins",
-B1:T [true] = {
-Sa:Sb a = "b",
-Sc:B0 c = false,
-E }
-E }
-
-String representations:
-In strings the following characters are escaped by &
-'&' -> '&&'
-(line break) -> '&n'
-(CR) -> '&r' --> required?
-':' -> '&:'
-All other characters are unchanged as they bear no special meaning.
-]]
-
-local write_table, literal_to_string, escape_chars, table_is_empty
-
-function table_is_empty(t)
- for _,_ in pairs(t) do
- return false
- end
- return true
-end
-
-function write_table(t, file, config)
- local ks, vs, writeit, istable
- for key, value in pairs(t) do
- ks = value_to_string(key, false)
- writeit = true
- istable = type(value)=="table"
-
- if istable then
- vs = "T"
- if config and config.skip_empty_tables then
- writeit = not table_is_empty(value)
- end
- else
- vs = value_to_string(value, true)
- end
-
- if writeit then
- file:write(ks..":"..vs.."\n")
-
- if istable then
- write_table(value, file, config)
- file:write("E\n")
- end
- end
- end
-end
-
-function value_to_string(t)
- if type(t)=="table" then
- file:close()
- error("Can not serialize a table in the key position!")
- elseif type(t)=="boolean" then
- if t then
- return "B1"
- else
- return "B0"
- end
- elseif type(t)=="number" then
- return "N"..t
- elseif type(t)=="string" then
- return "S"..escape_chars(t)
- else
- --error("Can not serialize '"..type(t).."' type!")
- return "S<function>"
- end
- return str
-end
-
-function escape_chars(str)
- local rstr = string.gsub(str, "&", "&&")
- rstr = string.gsub(rstr, ":", "&:")
- rstr = string.gsub(rstr, "\n", "&n")
- return rstr
-end
-
-------
-
-local read_table, string_to_value, unescape_chars
-
-function read_table(t, file)
- local line, ks, vs, kv, vv, vt
- while true do
- line = file:read("*l")
- if not line then
- file:close()
- error("Unexpected EOF or read error!")
- end
-
- if line=="E" then
- -- done with this table
- return
- end
- ks, vs = string.match(line, "^(.*[^&]):(.+)$")
- if not ks or not vs then
- file:close()
- error("Unable to parse line: '"..line.."'!")
- end
- kv = string_to_value(ks)
- vv, vt = string_to_value(vs, true)
- if vt then
- read_table(vv, file)
- end
- -- put read value in table
- t[kv] = vv
- end
-end
-
--- returns: value, is_table
-function string_to_value(str, table_allow)
- local first = string.sub(str, 1,1)
- local rest = string.sub(str, 2)
- if first=="T" then
- if table_allow then
- return {}, true
- else
- file:close()
- error("Table not allowed in key component!")
- end
- elseif first=="N" then
- local num = tonumber(rest)
- if num then
- return num
- else
- file:close()
- error("Unable to parse number: '"..rest.."'!")
- end
- elseif first=="B" then
- if rest=="0" then
- return false
- elseif rest=="1" then
- return true
- else
- file:close()
- error("Unable to parse boolean: '"..rest.."'!")
- end
- elseif first=="S" then
- return unescape_chars(rest)
- else
- file:close()
- error("Unknown literal type '"..first.."' for literal '"..str.."'!")
- end
-end
-
-function unescape_chars(str) --TODO
- local rstr = string.gsub(str, "&:", ":")
- rstr = string.gsub(rstr, "&n", "\n")
- rstr = string.gsub(rstr, "&&", "&")
- return rstr
-end
-
-------
-
---[[
-config = {
- skip_empty_tables = false -- if true, does not store empty tables
- -- On next read, keys that mapped to empty tables resolve to nil
-}
-]]
-
--- Writes the passed table into the passed file descriptor, and closes the file
-local function write_to_fd(root_table, file, config)
- file:write("LUA_SER v=1\n")
- write_table(root_table, file, config)
- file:write("E\nEND_SER\n")
- file:close()
-end
-
--- Reads the file contents from the passed file descriptor and returns the table on success
--- Throws errors when something is wrong. Closes the file.
--- config: see above
-local function read_from_fd(file)
- local first_line = file:read("*l")
- if first_line ~= "LUA_SER v=1" then
- file:close()
- error("Expected header, got '"..first_line.."' instead!")
- end
- local t = {}
- read_table(t, file)
- local last_line = file:read("*l")
- file:close()
- if last_line ~= "END_SER" then
- error("Missing END_SER, got '"..last_line.."' instead!")
- end
- return t
-end
-
--- Opens the passed filename and serializes root_table into it
--- config: see above
-function write_to_file(root_table, filename, config)
- -- try opening the file
- local file, err = io.open(filename, "w")
- if not file then
- error("Failed opening file '"..filename.."' for write:\n"..err)
- end
-
- write_to_fd(root_table, file, config)
- return true
-end
-
--- Opens the passed filename, and returns its deserialized contents
-function read_from_file(filename)
- -- try opening the file
- local file, err = io.open(filename, "r")
- if not file then
- error("Failed opening file '"..filename.."' for read:\n"..err)
- end
-
- return read_from_fd(file)
-end
-
---[[ simple unit test
-local testtable = {
- key = "value",
- [1] = "eins",
- [true] = {
- a = "b",
- c = false,
- },
- ["es:cape1"] = "foo:bar",
- ["es&ca\npe2"] = "baz&bam\nbim",
- ["es&&ca&\npe3"] = "baz&&bam&\nbim",
- ["es&:cape4"] = "foo\n:bar"
-}
-local config = {}
---write_to_file(testtable, "test_out", config)
-local t = read_from_file("test_out")
-write_to_file(t, "test_out_2", config)
-local t2 = read_from_file("test_out_2")
-write_to_file(t2, "test_out_3", config)
-
--- test_out_2 and test_out_3 should be equal
-
---]]
-
-
-return {
- read_from_fd = read_from_fd,
- write_to_fd = write_to_fd,
- read_from_file = read_from_file,
- write_to_file = write_to_file,
-}