From: Jan-Philipp Litza Date: Tue, 1 Sep 2015 16:17:23 +0200 Subject: luci-lib-jsonc: Add ltn12-compatible sink factory To use the luci-lib-jsonc parser as sink for an ltn12 pump (for example from stdin), the following code will now do: require 'luci.ltn12' require 'luci.jsonc' local parser = luci.jsonc.new() luci.ltn12.pump.all(luci.ltn12.source.file(io.input()), parser:sink()) print(parser:get()) Signed-off-by: Jan-Philipp Litza diff --git a/libs/luci-lib-jsonc/src/jsonc.c b/libs/luci-lib-jsonc/src/jsonc.c index b857c97..ef11101 100644 --- a/libs/luci-lib-jsonc/src/jsonc.c +++ b/libs/luci-lib-jsonc/src/jsonc.c @@ -328,6 +328,76 @@ static int json_parse_set(lua_State *L) return 0; } +static int json_parse_sink_closure(lua_State *L) +{ + bool finished = lua_toboolean(L, lua_upvalueindex(2)); + if (lua_isnil(L, 1)) + { + // no more data available + if (finished) + { + // we were finished parsing + lua_pushboolean(L, true); + return 1; + } + else + { + lua_pushnil(L); + lua_pushstring(L, "Incomplete JSON data"); + return 2; + } + } + else + { + if (finished) + { + lua_pushnil(L); + lua_pushstring(L, "Unexpected data after complete JSON object"); + return 2; + } + else + { + // luci.jsonc.parser.chunk() + lua_pushcfunction(L, json_parse_chunk); + // parser object from closure + lua_pushvalue(L, lua_upvalueindex(1)); + // chunk + lua_pushvalue(L, 1); + lua_call(L, 2, 2); + + if (lua_isnil(L, -2)) + { + // an error occurred, leave (nil, errmsg) on the stack and return it + return 2; + } + else if (lua_toboolean(L, -2)) + { + // finished reading, set finished=true and return nil to prevent further input + lua_pop(L, 2); + lua_pushboolean(L, true); + lua_replace(L, lua_upvalueindex(2)); + lua_pushnil(L); + return 1; + } + else + { + // not finished reading, return true + lua_pop(L, 2); + lua_pushboolean(L, true); + return 1; + } + } + } +} + +static int json_parse_sink(lua_State *L) +{ + luaL_checkudata(L, 1, LUCI_JSONC_PARSER); + lua_pushboolean(L, false); + lua_pushcclosure(L, json_parse_sink_closure, 2); + return 1; +} + static int json_tostring(lua_State *L) { struct json_state *s = luaL_checkudata(L, 1, LUCI_JSONC_PARSER); @@ -367,6 +437,7 @@ static const luaL_reg jsonc_parser_methods[] = { { "parse", json_parse_chunk }, { "get", json_parse_get }, { "set", json_parse_set }, + { "sink", json_parse_sink }, { "stringify", json_tostring }, { "__gc", json_gc }, diff --git a/libs/luci-lib-jsonc/src/jsonc.luadoc b/libs/luci-lib-jsonc/src/jsonc.luadoc index 2ee9ceb..720b17d 100644 --- a/libs/luci-lib-jsonc/src/jsonc.luadoc +++ b/libs/luci-lib-jsonc/src/jsonc.luadoc @@ -121,10 +121,22 @@ parser:set({ "some", "data" })` ]] ---[[ -Serialize current parser state as JSON. +Generate an ltn12-compatible sink. @class function @sort 4 +@name parser.sink +@return Returns a function that can be used as an ltn12 sink. +@usage `parser = luci.jsonc.new() +ltn12.pump.all(ltn12.source.file(io.input()), parser:sink()) +print(parser:get())` +]] + +---[[ +Serialize current parser state as JSON. + +@class function +@sort 5 @name parser.stringify @param pretty A boolean value indicating whether the resulting JSON should be pretty printed. @return Returns the serialized JSON data of this parser instance.