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- /* Copyright (c) 2014, Vsevolod Stakhov
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions are met:
- * * Redistributions of source code must retain the above copyright
- * notice, this list of conditions and the following disclaimer.
- * * Redistributions in binary form must reproduce the above copyright
- * notice, this list of conditions and the following disclaimer in the
- * documentation and/or other materials provided with the distribution.
- *
- * THIS SOFTWARE IS PROVIDED ''AS IS'' AND ANY
- * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
- * DISCLAIMED. IN NO EVENT SHALL AUTHOR BE LIABLE FOR ANY
- * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
- * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
- * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
- * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
- * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
- */
-
- /**
- * @file lua ucl bindings
- */
-
- #include "ucl.h"
- #include "ucl_internal.h"
- #include "lua_ucl.h"
- #include <strings.h>
-
- /***
- * @module ucl
- * This lua module allows to parse objects from strings and to store data into
- * ucl objects. It uses `libucl` C library to parse and manipulate with ucl objects.
- * @example
- local ucl = require("ucl")
-
- local parser = ucl.parser()
- local res,err = parser:parse_string('{key=value}')
-
- if not res then
- print('parser error: ' .. err)
- else
- local obj = parser:get_object()
- local got = ucl.to_format(obj, 'json')
- endif
-
- local table = {
- str = 'value',
- num = 100500,
- null = ucl.null,
- func = function ()
- return 'huh'
- end
- }
-
- print(ucl.to_format(table, 'ucl'))
- -- Output:
- --[[
- num = 100500;
- str = "value";
- null = null;
- func = "huh";
- --]]
- */
-
- #define PARSER_META "ucl.parser.meta"
- #define EMITTER_META "ucl.emitter.meta"
- #define NULL_META "null.emitter.meta"
-
- static int ucl_object_lua_push_array (lua_State *L, const ucl_object_t *obj);
- static int ucl_object_lua_push_scalar (lua_State *L, const ucl_object_t *obj, bool allow_array);
- static ucl_object_t* ucl_object_lua_fromtable (lua_State *L, int idx);
- static ucl_object_t* ucl_object_lua_fromelt (lua_State *L, int idx);
-
- static void *ucl_null;
-
- /**
- * Push a single element of an object to lua
- * @param L
- * @param key
- * @param obj
- */
- static void
- ucl_object_lua_push_element (lua_State *L, const char *key,
- const ucl_object_t *obj)
- {
- lua_pushstring (L, key);
- ucl_object_push_lua (L, obj, true);
- lua_settable (L, -3);
- }
-
- static void
- lua_ucl_userdata_dtor (void *ud)
- {
- struct ucl_lua_funcdata *fd = (struct ucl_lua_funcdata *)ud;
-
- luaL_unref (fd->L, LUA_REGISTRYINDEX, fd->idx);
- if (fd->ret != NULL) {
- free (fd->ret);
- }
- free (fd);
- }
-
- static const char *
- lua_ucl_userdata_emitter (void *ud)
- {
- struct ucl_lua_funcdata *fd = (struct ucl_lua_funcdata *)ud;
- const char *out = "";
-
- lua_rawgeti (fd->L, LUA_REGISTRYINDEX, fd->idx);
-
- lua_pcall (fd->L, 0, 1, 0);
- out = lua_tostring (fd->L, -1);
-
- if (out != NULL) {
- /* We need to store temporary string in a more appropriate place */
- if (fd->ret) {
- free (fd->ret);
- }
- fd->ret = strdup (out);
- }
-
- lua_settop (fd->L, 0);
-
- return fd->ret;
- }
-
- /**
- * Push a single object to lua
- * @param L
- * @param obj
- * @return
- */
- static int
- ucl_object_lua_push_object (lua_State *L, const ucl_object_t *obj,
- bool allow_array)
- {
- const ucl_object_t *cur;
- ucl_object_iter_t it = NULL;
- int nelt = 0;
-
- if (allow_array && obj->next != NULL) {
- /* Actually we need to push this as an array */
- return ucl_object_lua_push_array (L, obj);
- }
-
- /* Optimize allocation by preallocation of table */
- while (ucl_iterate_object (obj, &it, true) != NULL) {
- nelt ++;
- }
-
- lua_createtable (L, 0, nelt);
- it = NULL;
-
- while ((cur = ucl_iterate_object (obj, &it, true)) != NULL) {
- ucl_object_lua_push_element (L, ucl_object_key (cur), cur);
- }
-
- return 1;
- }
-
- /**
- * Push an array to lua as table indexed by integers
- * @param L
- * @param obj
- * @return
- */
- static int
- ucl_object_lua_push_array (lua_State *L, const ucl_object_t *obj)
- {
- const ucl_object_t *cur;
- int i = 1, nelt = 0;
-
- /* Optimize allocation by preallocation of table */
- LL_FOREACH (obj, cur) {
- nelt ++;
- }
-
- lua_createtable (L, nelt, 0);
-
- LL_FOREACH (obj, cur) {
- ucl_object_push_lua (L, cur, false);
- lua_rawseti (L, -2, i);
- i ++;
- }
-
- return 1;
- }
-
- /**
- * Push a simple object to lua depending on its actual type
- */
- static int
- ucl_object_lua_push_scalar (lua_State *L, const ucl_object_t *obj,
- bool allow_array)
- {
- struct ucl_lua_funcdata *fd;
-
- if (allow_array && obj->next != NULL) {
- /* Actually we need to push this as an array */
- return ucl_object_lua_push_array (L, obj);
- }
-
- switch (obj->type) {
- case UCL_BOOLEAN:
- lua_pushboolean (L, ucl_obj_toboolean (obj));
- break;
- case UCL_STRING:
- lua_pushstring (L, ucl_obj_tostring (obj));
- break;
- case UCL_INT:
- #if LUA_VERSION_NUM >= 501
- lua_pushinteger (L, ucl_obj_toint (obj));
- #else
- lua_pushnumber (L, ucl_obj_toint (obj));
- #endif
- break;
- case UCL_FLOAT:
- case UCL_TIME:
- lua_pushnumber (L, ucl_obj_todouble (obj));
- break;
- case UCL_NULL:
- lua_getfield (L, LUA_REGISTRYINDEX, "ucl.null");
- break;
- case UCL_USERDATA:
- fd = (struct ucl_lua_funcdata *)obj->value.ud;
- lua_rawgeti (L, LUA_REGISTRYINDEX, fd->idx);
- break;
- default:
- lua_pushnil (L);
- break;
- }
-
- return 1;
- }
-
- /***
- * @function ucl_object_push_lua(L, obj, allow_array)
- * This is a `C` function to push `UCL` object as lua variable. This function
- * converts `obj` to lua representation using the following conversions:
- *
- * - *scalar* values are directly presented by lua objects
- * - *userdata* values are converted to lua function objects using `LUA_REGISTRYINDEX`,
- * this can be used to pass functions from lua to c and vice-versa
- * - *arrays* are converted to lua tables with numeric indicies suitable for `ipairs` iterations
- * - *objects* are converted to lua tables with string indicies
- * @param {lua_State} L lua state pointer
- * @param {ucl_object_t} obj object to push
- * @param {bool} allow_array expand implicit arrays (should be true for all but partial arrays)
- * @return {int} `1` if an object is pushed to lua
- */
- int
- ucl_object_push_lua (lua_State *L, const ucl_object_t *obj, bool allow_array)
- {
- switch (obj->type) {
- case UCL_OBJECT:
- return ucl_object_lua_push_object (L, obj, allow_array);
- case UCL_ARRAY:
- return ucl_object_lua_push_array (L, obj->value.av);
- default:
- return ucl_object_lua_push_scalar (L, obj, allow_array);
- }
- }
-
- /**
- * Parse lua table into object top
- * @param L
- * @param top
- * @param idx
- */
- static ucl_object_t *
- ucl_object_lua_fromtable (lua_State *L, int idx)
- {
- ucl_object_t *obj, *top = NULL;
- size_t keylen;
- const char *k;
- bool is_array = true;
- int max = INT_MIN;
-
- if (idx < 0) {
- /* For negative indicies we want to invert them */
- idx = lua_gettop (L) + idx + 1;
- }
- /* Check for array */
- lua_pushnil (L);
- while (lua_next (L, idx) != 0) {
- if (lua_type (L, -2) == LUA_TNUMBER) {
- double num = lua_tonumber (L, -2);
- if (num == (int)num) {
- if (num > max) {
- max = num;
- }
- }
- else {
- /* Keys are not integer */
- lua_pop (L, 2);
- is_array = false;
- break;
- }
- }
- else {
- /* Keys are not numeric */
- lua_pop (L, 2);
- is_array = false;
- break;
- }
- lua_pop (L, 1);
- }
-
- /* Table iterate */
- if (is_array) {
- int i;
-
- top = ucl_object_typed_new (UCL_ARRAY);
- for (i = 1; i <= max; i ++) {
- lua_pushinteger (L, i);
- lua_gettable (L, idx);
- obj = ucl_object_lua_fromelt (L, lua_gettop (L));
- if (obj != NULL) {
- ucl_array_append (top, obj);
- }
- }
- }
- else {
- lua_pushnil (L);
- top = ucl_object_typed_new (UCL_OBJECT);
- while (lua_next (L, idx) != 0) {
- /* copy key to avoid modifications */
- k = lua_tolstring (L, -2, &keylen);
- obj = ucl_object_lua_fromelt (L, lua_gettop (L));
-
- if (obj != NULL) {
- ucl_object_insert_key (top, obj, k, keylen, true);
- }
- lua_pop (L, 1);
- }
- }
-
- return top;
- }
-
- /**
- * Get a single element from lua to object obj
- * @param L
- * @param obj
- * @param idx
- */
- static ucl_object_t *
- ucl_object_lua_fromelt (lua_State *L, int idx)
- {
- int type;
- double num;
- ucl_object_t *obj = NULL;
- struct ucl_lua_funcdata *fd;
-
- type = lua_type (L, idx);
-
- switch (type) {
- case LUA_TSTRING:
- obj = ucl_object_fromstring_common (lua_tostring (L, idx), 0, 0);
- break;
- case LUA_TNUMBER:
- num = lua_tonumber (L, idx);
- if (num == (int64_t)num) {
- obj = ucl_object_fromint (num);
- }
- else {
- obj = ucl_object_fromdouble (num);
- }
- break;
- case LUA_TBOOLEAN:
- obj = ucl_object_frombool (lua_toboolean (L, idx));
- break;
- case LUA_TUSERDATA:
- if (lua_topointer (L, idx) == ucl_null) {
- obj = ucl_object_typed_new (UCL_NULL);
- }
- break;
- case LUA_TTABLE:
- case LUA_TFUNCTION:
- case LUA_TTHREAD:
- if (luaL_getmetafield (L, idx, "__gen_ucl")) {
- if (lua_isfunction (L, -1)) {
- lua_settop (L, 3); /* gen, obj, func */
- lua_insert (L, 1); /* func, gen, obj */
- lua_insert (L, 2); /* func, obj, gen */
- lua_call(L, 2, 1);
- obj = ucl_object_lua_fromelt (L, 1);
- }
- lua_pop (L, 2);
- }
- else {
- if (type == LUA_TTABLE) {
- obj = ucl_object_lua_fromtable (L, idx);
- }
- else if (type == LUA_TFUNCTION) {
- fd = malloc (sizeof (*fd));
- if (fd != NULL) {
- lua_pushvalue (L, idx);
- fd->L = L;
- fd->ret = NULL;
- fd->idx = luaL_ref (L, LUA_REGISTRYINDEX);
-
- obj = ucl_object_new_userdata (lua_ucl_userdata_dtor,
- lua_ucl_userdata_emitter);
- obj->type = UCL_USERDATA;
- obj->value.ud = (void *)fd;
- }
- }
- }
- break;
- }
-
- return obj;
- }
-
- /**
- * @function ucl_object_lua_import(L, idx)
- * Extracts ucl object from lua variable at `idx` position,
- * @see ucl_object_push_lua for conversion definitions
- * @param {lua_state} L lua state machine pointer
- * @param {int} idx index where the source variable is placed
- * @return {ucl_object_t} new ucl object extracted from lua variable. Reference count of this object is 1,
- * this object thus needs to be unref'ed after usage.
- */
- ucl_object_t *
- ucl_object_lua_import (lua_State *L, int idx)
- {
- ucl_object_t *obj;
- int t;
-
- t = lua_type (L, idx);
- switch (t) {
- case LUA_TTABLE:
- obj = ucl_object_lua_fromtable (L, idx);
- break;
- default:
- obj = ucl_object_lua_fromelt (L, idx);
- break;
- }
-
- return obj;
- }
-
- static int
- lua_ucl_parser_init (lua_State *L)
- {
- struct ucl_parser *parser, **pparser;
- int flags = 0;
-
- if (lua_gettop (L) >= 1) {
- flags = lua_tonumber (L, 1);
- }
-
- parser = ucl_parser_new (flags);
- if (parser == NULL) {
- lua_pushnil (L);
- }
-
- pparser = lua_newuserdata (L, sizeof (parser));
- *pparser = parser;
- luaL_getmetatable (L, PARSER_META);
- lua_setmetatable (L, -2);
-
- return 1;
- }
-
- static struct ucl_parser *
- lua_ucl_parser_get (lua_State *L, int index)
- {
- return *((struct ucl_parser **) luaL_checkudata(L, index, PARSER_META));
- }
-
- /***
- * @method parser:parse_file(name)
- * Parse UCL object from file.
- * @param {string} name filename to parse
- * @return {bool[, string]} if res is `true` then file has been parsed successfully, otherwise an error string is also returned
- @example
- local parser = ucl.parser()
- local res,err = parser:parse_file('/some/file.conf')
-
- if not res then
- print('parser error: ' .. err)
- else
- -- Do something with object
- end
- */
- static int
- lua_ucl_parser_parse_file (lua_State *L)
- {
- struct ucl_parser *parser;
- const char *file;
- int ret = 2;
-
- parser = lua_ucl_parser_get (L, 1);
- file = luaL_checkstring (L, 2);
-
- if (parser != NULL && file != NULL) {
- if (ucl_parser_add_file (parser, file)) {
- lua_pushboolean (L, true);
- ret = 1;
- }
- else {
- lua_pushboolean (L, false);
- lua_pushstring (L, ucl_parser_get_error (parser));
- }
- }
- else {
- lua_pushboolean (L, false);
- lua_pushstring (L, "invalid arguments");
- }
-
- return ret;
- }
-
- /***
- * @method parser:parse_string(input)
- * Parse UCL object from file.
- * @param {string} input string to parse
- * @return {bool[, string]} if res is `true` then file has been parsed successfully, otherwise an error string is also returned
- */
- static int
- lua_ucl_parser_parse_string (lua_State *L)
- {
- struct ucl_parser *parser;
- const char *string;
- size_t llen;
- int ret = 2;
-
- parser = lua_ucl_parser_get (L, 1);
- string = luaL_checklstring (L, 2, &llen);
-
- if (parser != NULL && string != NULL) {
- if (ucl_parser_add_chunk (parser, (const unsigned char *)string, llen)) {
- lua_pushboolean (L, true);
- ret = 1;
- }
- else {
- lua_pushboolean (L, false);
- lua_pushstring (L, ucl_parser_get_error (parser));
- }
- }
- else {
- lua_pushboolean (L, false);
- lua_pushstring (L, "invalid arguments");
- }
-
- return ret;
- }
-
- /***
- * @method parser:get_object()
- * Get top object from parser and export it to lua representation.
- * @return {variant or nil} ucl object as lua native variable
- */
- static int
- lua_ucl_parser_get_object (lua_State *L)
- {
- struct ucl_parser *parser;
- ucl_object_t *obj;
- int ret = 1;
-
- parser = lua_ucl_parser_get (L, 1);
- obj = ucl_parser_get_object (parser);
-
- if (obj != NULL) {
- ret = ucl_object_push_lua (L, obj, false);
- /* no need to keep reference */
- ucl_object_unref (obj);
- }
- else {
- lua_pushnil (L);
- }
-
- return ret;
- }
-
- static int
- lua_ucl_parser_gc (lua_State *L)
- {
- struct ucl_parser *parser;
-
- parser = lua_ucl_parser_get (L, 1);
- ucl_parser_free (parser);
-
- return 0;
- }
-
- static void
- lua_ucl_parser_mt (lua_State *L)
- {
- luaL_newmetatable (L, PARSER_META);
-
- lua_pushvalue(L, -1);
- lua_setfield(L, -2, "__index");
-
- lua_pushcfunction (L, lua_ucl_parser_gc);
- lua_setfield (L, -2, "__gc");
-
- lua_pushcfunction (L, lua_ucl_parser_parse_file);
- lua_setfield (L, -2, "parse_file");
-
- lua_pushcfunction (L, lua_ucl_parser_parse_string);
- lua_setfield (L, -2, "parse_string");
-
- lua_pushcfunction (L, lua_ucl_parser_get_object);
- lua_setfield (L, -2, "get_object");
-
- lua_pop (L, 1);
- }
-
- static int
- lua_ucl_to_string (lua_State *L, const ucl_object_t *obj, enum ucl_emitter type)
- {
- unsigned char *result;
-
- result = ucl_object_emit (obj, type);
-
- if (result != NULL) {
- lua_pushstring (L, (const char *)result);
- free (result);
- }
- else {
- lua_pushnil (L);
- }
-
- return 1;
- }
-
- static int
- lua_ucl_to_json (lua_State *L)
- {
- ucl_object_t *obj;
- int format = UCL_EMIT_JSON;
-
- if (lua_gettop (L) > 1) {
- if (lua_toboolean (L, 2)) {
- format = UCL_EMIT_JSON_COMPACT;
- }
- }
-
- obj = ucl_object_lua_import (L, 1);
- if (obj != NULL) {
- lua_ucl_to_string (L, obj, format);
- ucl_object_unref (obj);
- }
- else {
- lua_pushnil (L);
- }
-
- return 1;
- }
-
- static int
- lua_ucl_to_config (lua_State *L)
- {
- ucl_object_t *obj;
-
- obj = ucl_object_lua_import (L, 1);
- if (obj != NULL) {
- lua_ucl_to_string (L, obj, UCL_EMIT_CONFIG);
- ucl_object_unref (obj);
- }
- else {
- lua_pushnil (L);
- }
-
- return 1;
- }
-
- /***
- * @function ucl.to_format(var, format)
- * Converts lua variable `var` to the specified `format`. Formats supported are:
- *
- * - `json` - fine printed json
- * - `json-compact` - compacted json
- * - `config` - fine printed configuration
- * - `ucl` - same as `config`
- * - `yaml` - embedded yaml
- *
- * If `var` contains function, they are called during output formatting and if
- * they return string value, then this value is used for ouptut.
- * @param {variant} var any sort of lua variable (if userdata then metafield `__to_ucl` is searched for output)
- * @param {string} format any available format
- * @return {string} string representation of `var` in the specific `format`.
- * @example
- local table = {
- str = 'value',
- num = 100500,
- null = ucl.null,
- func = function ()
- return 'huh'
- end
- }
-
- print(ucl.to_format(table, 'ucl'))
- -- Output:
- --[[
- num = 100500;
- str = "value";
- null = null;
- func = "huh";
- --]]
- */
- static int
- lua_ucl_to_format (lua_State *L)
- {
- ucl_object_t *obj;
- int format = UCL_EMIT_JSON;
-
- if (lua_gettop (L) > 1) {
- if (lua_type (L, 2) == LUA_TNUMBER) {
- format = lua_tonumber (L, 2);
- if (format < 0 || format >= UCL_EMIT_YAML) {
- lua_pushnil (L);
- return 1;
- }
- }
- else if (lua_type (L, 2) == LUA_TSTRING) {
- const char *strtype = lua_tostring (L, 2);
-
- if (strcasecmp (strtype, "json") == 0) {
- format = UCL_EMIT_JSON;
- }
- else if (strcasecmp (strtype, "json-compact") == 0) {
- format = UCL_EMIT_JSON_COMPACT;
- }
- else if (strcasecmp (strtype, "yaml") == 0) {
- format = UCL_EMIT_YAML;
- }
- else if (strcasecmp (strtype, "config") == 0 ||
- strcasecmp (strtype, "ucl") == 0) {
- format = UCL_EMIT_CONFIG;
- }
- }
- }
-
- obj = ucl_object_lua_import (L, 1);
- if (obj != NULL) {
- lua_ucl_to_string (L, obj, format);
- ucl_object_unref (obj);
- }
- else {
- lua_pushnil (L);
- }
-
- return 1;
- }
-
- static int
- lua_ucl_null_tostring (lua_State* L)
- {
- lua_pushstring (L, "null");
- return 1;
- }
-
- static void
- lua_ucl_null_mt (lua_State *L)
- {
- luaL_newmetatable (L, NULL_META);
-
- lua_pushcfunction (L, lua_ucl_null_tostring);
- lua_setfield (L, -2, "__tostring");
-
- lua_pop (L, 1);
- }
-
- int
- luaopen_ucl (lua_State *L)
- {
- lua_ucl_parser_mt (L);
- lua_ucl_null_mt (L);
-
- /* Create the refs weak table: */
- lua_createtable (L, 0, 2);
- lua_pushliteral (L, "v"); /* tbl, "v" */
- lua_setfield (L, -2, "__mode");
- lua_pushvalue (L, -1); /* tbl, tbl */
- lua_setmetatable (L, -2); /* tbl */
- lua_setfield (L, LUA_REGISTRYINDEX, "ucl.refs");
-
- lua_newtable (L);
-
- lua_pushcfunction (L, lua_ucl_parser_init);
- lua_setfield (L, -2, "parser");
-
- lua_pushcfunction (L, lua_ucl_to_json);
- lua_setfield (L, -2, "to_json");
-
- lua_pushcfunction (L, lua_ucl_to_config);
- lua_setfield (L, -2, "to_config");
-
- lua_pushcfunction (L, lua_ucl_to_format);
- lua_setfield (L, -2, "to_format");
-
- ucl_null = lua_newuserdata (L, 0);
- luaL_getmetatable (L, NULL_META);
- lua_setmetatable (L, -2);
-
- lua_pushvalue (L, -1);
- lua_setfield (L, LUA_REGISTRYINDEX, "ucl.null");
-
- lua_setfield (L, -2, "null");
-
- return 1;
- }
-
- struct ucl_lua_funcdata*
- ucl_object_toclosure (const ucl_object_t *obj)
- {
- if (obj == NULL || obj->type != UCL_USERDATA) {
- return NULL;
- }
-
- return (struct ucl_lua_funcdata*)obj->value.ud;
- }
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