diff options
Diffstat (limited to 'src')
-rw-r--r-- | src/common.h | 21 | ||||
-rw-r--r-- | src/honey_lua.c | 26 |
2 files changed, 47 insertions, 0 deletions
diff --git a/src/common.h b/src/common.h index cb0ba45..03d6944 100644 --- a/src/common.h +++ b/src/common.h @@ -153,6 +153,27 @@ typedef enum { */ int honey_lua_parse_arguments(lua_State* L, unsigned int n, ...); +/** @brief Process a param table. + * + * Please ensure that the param table is on top of the stack before calling this function. + * + * The first m elements of the param table are required, and their absence from + * the table will trigger an error. + * + * The variadic portion of this function expects arguments as + * param_name_1, function1, (void*) data1, param_name_2, function_2, (void*) data_2, ... + * + * Each function should be of the form void (*)(lua_State*, void*) + * + * @param[in] L The lua state to parse the table from. + * @param[in] n The number of params to parse. + * @param[in] m The number of required params. + * @param[inout] ... Variadic list of param processing functions, as described above. + * + * @returns Nothing, but throws a lua error if a required argument is not found. + */ +void honey_lua_parse_params(lua_State* L, int n, int m, ...); + /** @brief Wrap C objects for lua. */ typedef struct honey_lua_element { char* name; diff --git a/src/honey_lua.c b/src/honey_lua.c index f3ca0a5..ff1d82d 100644 --- a/src/honey_lua.c +++ b/src/honey_lua.c @@ -247,6 +247,32 @@ int honey_lua_parse_arguments(lua_State* L, unsigned int n, ...) return index; } +/* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ */ + +void honey_lua_parse_params(lua_State* L, int n, int m, ...) +{ + int table_index = lua_gettop(L); + + va_list args; + va_start(args, m); + + for (int i=0; i<n; i++) { + const char* param = va_arg(args, const char*); + void (*function)(lua_State*, void*) = va_arg(args, void (*)(lua_State*, void*)); + void* data = va_arg(args, void*); + + lua_getfield(L, table_index, param); + if (lua_isnil(L, -1) && n < m) + honey_lua_throw_error + (L, "required parameter '%s' was not found in param table!", param); + + function(L, data); + lua_pop(L, 1); + } + + va_end(args); +} + /* ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * * Table creation functions |