/* Interface between gdb and its extension languages. Copyright (C) 2014-2019 Free Software Foundation, Inc. This file is part of GDB. 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 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see <http://www.gnu.org/licenses/>. */ #ifndef EXTENSION_H #define EXTENSION_H #include "mi/mi-cmds.h" /* For PRINT_NO_VALUES, etc. */ #include "gdbsupport/vec.h" #include "gdbsupport/array-view.h" struct breakpoint; struct command_line; struct frame_info; struct language_defn; struct objfile; struct extension_language_defn; struct type; struct ui_file; struct ui_out; struct value; struct value_print_options; /* A function to load and process a script file. The file has been opened and is ready to be read from the beginning. Any exceptions are not caught, and are passed to the caller. */ typedef void script_sourcer_func (const struct extension_language_defn *, FILE *stream, const char *filename); /* A function to load and process a script for an objfile. The file has been opened and is ready to be read from the beginning. Any exceptions are not caught, and are passed to the caller. */ typedef void objfile_script_sourcer_func (const struct extension_language_defn *, struct objfile *, FILE *stream, const char *filename); /* A function to execute a script for an objfile. Any exceptions are not caught, and are passed to the caller. */ typedef void objfile_script_executor_func (const struct extension_language_defn *, struct objfile *, const char *name, const char *script); /* Enum of each extension(/scripting) language. */ enum extension_language { EXT_LANG_NONE, EXT_LANG_GDB, EXT_LANG_PYTHON, EXT_LANG_GUILE }; /* Extension language frame-filter status return values. */ enum ext_lang_bt_status { /* Return when an error has occurred in processing frame filters, or when printing the stack. */ EXT_LANG_BT_ERROR = -1, /* Return from internal routines to indicate that the function succeeded. */ EXT_LANG_BT_OK = 1, /* Return when the frame filter process is complete, but there were no filter registered and enabled to process. */ EXT_LANG_BT_NO_FILTERS = 2 }; /* Flags to pass to apply_extlang_frame_filter. */ enum frame_filter_flag { /* Set this flag if frame level is to be printed. */ PRINT_LEVEL = 1 << 0, /* Set this flag if frame information is to be printed. */ PRINT_FRAME_INFO = 1 << 1, /* Set this flag if frame arguments are to be printed. */ PRINT_ARGS = 1 << 2, /* Set this flag if frame locals are to be printed. */ PRINT_LOCALS = 1 << 3, /* Set this flag if a "More frames" message is to be printed. */ PRINT_MORE_FRAMES = 1 << 4, /* Set this flag if elided frames should not be printed. */ PRINT_HIDE = 1 << 5, }; DEF_ENUM_FLAGS_TYPE (enum frame_filter_flag, frame_filter_flags); /* A choice of the different frame argument printing strategies that can occur in different cases of frame filter instantiation. */ enum ext_lang_frame_args { /* Print no values for arguments when invoked from the MI. */ NO_VALUES = PRINT_NO_VALUES, MI_PRINT_ALL_VALUES = PRINT_ALL_VALUES, /* Print only simple values (what MI defines as "simple") for arguments when invoked from the MI. */ MI_PRINT_SIMPLE_VALUES = PRINT_SIMPLE_VALUES, /* Print only scalar values for arguments when invoked from the CLI. */ CLI_SCALAR_VALUES, /* Print all values for arguments when invoked from the CLI. */ CLI_ALL_VALUES }; /* The possible results of extension_language_ops.breakpoint_cond_says_stop. */ enum ext_lang_bp_stop { /* No "stop" condition is set. */ EXT_LANG_BP_STOP_UNSET, /* A "stop" condition is set, and it says "don't stop". */ EXT_LANG_BP_STOP_NO, /* A "stop" condition is set, and it says "stop". */ EXT_LANG_BP_STOP_YES }; /* Table of type printers associated with the global typedef table. */ struct ext_lang_type_printers { ext_lang_type_printers (); ~ext_lang_type_printers (); DISABLE_COPY_AND_ASSIGN (ext_lang_type_printers); /* Type-printers from Python. */ void *py_type_printers = nullptr; }; /* The return code for some API calls. */ enum ext_lang_rc { /* The operation completed successfully. */ EXT_LANG_RC_OK, /* The operation was not performed (e.g., no pretty-printer). */ EXT_LANG_RC_NOP, /* There was an error (e.g., Python error while printing a value). When an error occurs no further extension languages are tried. This is to preserve existing behaviour, and because it's convenient for Python developers. Note: This is different than encountering a memory error trying to read a value for pretty-printing. Here we're referring to, e.g., programming errors that trigger an exception in the extension language. */ EXT_LANG_RC_ERROR }; /* A type which holds its extension language specific xmethod worker data. */ struct xmethod_worker { xmethod_worker (const extension_language_defn *extlang) : m_extlang (extlang) {} virtual ~xmethod_worker () = default; /* Invoke the xmethod encapsulated in this worker and return the result. The method is invoked on OBJ with arguments in the ARGS array. */ virtual value *invoke (value *obj, gdb::array_view<value *> args) = 0; /* Return the arg types of the xmethod encapsulated in this worker. The type of the 'this' object is returned as the first element of the vector. */ std::vector<type *> get_arg_types (); /* Return the type of the result of the xmethod encapsulated in this worker. OBJECT and ARGS are the same as for invoke. */ type *get_result_type (value *object, gdb::array_view<value *> args); private: /* Return the types of the arguments the method takes. The types are returned in TYPE_ARGS, one per argument. */ virtual enum ext_lang_rc do_get_arg_types (std::vector<type *> *type_args) = 0; /* Fetch the type of the result of the method implemented by this worker. OBJECT and ARGS are the same as for the invoked method. The result type is stored in *RESULT_TYPE. */ virtual enum ext_lang_rc do_get_result_type (struct value *obj, gdb::array_view<value *> args, struct type **result_type_ptr) = 0; /* The language the xmethod worker is implemented in. */ const extension_language_defn *m_extlang; }; typedef std::unique_ptr<xmethod_worker> xmethod_worker_up; /* The interface for gdb's own extension(/scripting) language. */ extern const struct extension_language_defn extension_language_gdb; extern const struct extension_language_defn *get_ext_lang_defn (enum extension_language lang); extern const struct extension_language_defn *get_ext_lang_of_file (const char *file); extern int ext_lang_present_p (const struct extension_language_defn *); extern int ext_lang_initialized_p (const struct extension_language_defn *); extern void throw_ext_lang_unsupported (const struct extension_language_defn *); /* Accessors for "public" attributes of the extension language definition. */ extern enum extension_language ext_lang_kind (const struct extension_language_defn *); extern const char *ext_lang_name (const struct extension_language_defn *); extern const char *ext_lang_capitalized_name (const struct extension_language_defn *); extern const char *ext_lang_suffix (const struct extension_language_defn *); extern const char *ext_lang_auto_load_suffix (const struct extension_language_defn *); extern script_sourcer_func *ext_lang_script_sourcer (const struct extension_language_defn *); extern objfile_script_sourcer_func *ext_lang_objfile_script_sourcer (const struct extension_language_defn *); extern objfile_script_executor_func *ext_lang_objfile_script_executor (const struct extension_language_defn *); extern int ext_lang_auto_load_enabled (const struct extension_language_defn *); /* Wrappers for each extension language API function that iterate over all extension languages. */ extern void finish_ext_lang_initialization (void); extern void eval_ext_lang_from_control_command (struct command_line *cmd); extern void auto_load_ext_lang_scripts_for_objfile (struct objfile *); extern char *apply_ext_lang_type_printers (struct ext_lang_type_printers *, struct type *); extern int apply_ext_lang_val_pretty_printer (struct type *type, LONGEST embedded_offset, CORE_ADDR address, struct ui_file *stream, int recurse, struct value *val, const struct value_print_options *options, const struct language_defn *language); extern enum ext_lang_bt_status apply_ext_lang_frame_filter (struct frame_info *frame, frame_filter_flags flags, enum ext_lang_frame_args args_type, struct ui_out *out, int frame_low, int frame_high); extern void preserve_ext_lang_values (struct objfile *, htab_t copied_types); extern const struct extension_language_defn *get_breakpoint_cond_ext_lang (struct breakpoint *b, enum extension_language skip_lang); extern int breakpoint_ext_lang_cond_says_stop (struct breakpoint *); /* If a method with name METHOD_NAME is to be invoked on an object of type TYPE, then all extension languages are searched for implementations of methods with name METHOD_NAME. All matches found are appended to the WORKERS vector. */ extern void get_matching_xmethod_workers (struct type *type, const char *method_name, std::vector<xmethod_worker_up> *workers); #endif /* EXTENSION_H */