| 1 | /* Interface between gdb and its extension languages. |
| 2 | |
| 3 | Copyright (C) 2014-2019 Free Software Foundation, Inc. |
| 4 | |
| 5 | This file is part of GDB. |
| 6 | |
| 7 | This program is free software; you can redistribute it and/or modify |
| 8 | it under the terms of the GNU General Public License as published by |
| 9 | the Free Software Foundation; either version 3 of the License, or |
| 10 | (at your option) any later version. |
| 11 | |
| 12 | This program is distributed in the hope that it will be useful, |
| 13 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | GNU General Public License for more details. |
| 16 | |
| 17 | You should have received a copy of the GNU General Public License |
| 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
| 19 | |
| 20 | #ifndef EXTENSION_H |
| 21 | #define EXTENSION_H |
| 22 | |
| 23 | #include "common/array-view.h" |
| 24 | #include "common/vec.h" |
| 25 | #include "mi/mi-cmds.h" |
| 26 | |
| 27 | struct breakpoint; |
| 28 | struct command_line; |
| 29 | struct frame_info; |
| 30 | struct language_defn; |
| 31 | struct objfile; |
| 32 | struct extension_language_defn; |
| 33 | struct type; |
| 34 | struct ui_file; |
| 35 | struct ui_out; |
| 36 | struct value; |
| 37 | struct value_print_options; |
| 38 | |
| 39 | /* A function to load and process a script file. |
| 40 | The file has been opened and is ready to be read from the beginning. |
| 41 | Any exceptions are not caught, and are passed to the caller. */ |
| 42 | typedef void script_sourcer_func (const struct extension_language_defn *, |
| 43 | FILE *stream, const char *filename); |
| 44 | |
| 45 | /* A function to load and process a script for an objfile. |
| 46 | The file has been opened and is ready to be read from the beginning. |
| 47 | Any exceptions are not caught, and are passed to the caller. */ |
| 48 | typedef void objfile_script_sourcer_func |
| 49 | (const struct extension_language_defn *, |
| 50 | struct objfile *, FILE *stream, const char *filename); |
| 51 | |
| 52 | /* A function to execute a script for an objfile. |
| 53 | Any exceptions are not caught, and are passed to the caller. */ |
| 54 | typedef void objfile_script_executor_func |
| 55 | (const struct extension_language_defn *, |
| 56 | struct objfile *, const char *name, const char *script); |
| 57 | |
| 58 | /* Enum of each extension(/scripting) language. */ |
| 59 | |
| 60 | enum extension_language |
| 61 | { |
| 62 | EXT_LANG_NONE, |
| 63 | EXT_LANG_GDB, |
| 64 | EXT_LANG_PYTHON, |
| 65 | EXT_LANG_GUILE |
| 66 | }; |
| 67 | |
| 68 | /* Extension language frame-filter status return values. */ |
| 69 | |
| 70 | enum ext_lang_bt_status |
| 71 | { |
| 72 | /* Return when an error has occurred in processing frame filters, |
| 73 | or when printing the stack. */ |
| 74 | EXT_LANG_BT_ERROR = -1, |
| 75 | |
| 76 | /* Return from internal routines to indicate that the function |
| 77 | succeeded. */ |
| 78 | EXT_LANG_BT_OK = 1, |
| 79 | |
| 80 | /* Return when the frame filter process is complete, but there |
| 81 | were no filter registered and enabled to process. */ |
| 82 | EXT_LANG_BT_NO_FILTERS = 2 |
| 83 | }; |
| 84 | |
| 85 | /* Flags to pass to apply_extlang_frame_filter. */ |
| 86 | |
| 87 | enum frame_filter_flag |
| 88 | { |
| 89 | /* Set this flag if frame level is to be printed. */ |
| 90 | PRINT_LEVEL = 1 << 0, |
| 91 | |
| 92 | /* Set this flag if frame information is to be printed. */ |
| 93 | PRINT_FRAME_INFO = 1 << 1, |
| 94 | |
| 95 | /* Set this flag if frame arguments are to be printed. */ |
| 96 | PRINT_ARGS = 1 << 2, |
| 97 | |
| 98 | /* Set this flag if frame locals are to be printed. */ |
| 99 | PRINT_LOCALS = 1 << 3, |
| 100 | |
| 101 | /* Set this flag if a "More frames" message is to be printed. */ |
| 102 | PRINT_MORE_FRAMES = 1 << 4, |
| 103 | |
| 104 | /* Set this flag if elided frames should not be printed. */ |
| 105 | PRINT_HIDE = 1 << 5, |
| 106 | }; |
| 107 | |
| 108 | DEF_ENUM_FLAGS_TYPE (enum frame_filter_flag, frame_filter_flags); |
| 109 | |
| 110 | /* A choice of the different frame argument printing strategies that |
| 111 | can occur in different cases of frame filter instantiation. */ |
| 112 | |
| 113 | enum ext_lang_frame_args |
| 114 | { |
| 115 | /* Print no values for arguments when invoked from the MI. */ |
| 116 | NO_VALUES = PRINT_NO_VALUES, |
| 117 | |
| 118 | MI_PRINT_ALL_VALUES = PRINT_ALL_VALUES, |
| 119 | |
| 120 | /* Print only simple values (what MI defines as "simple") for |
| 121 | arguments when invoked from the MI. */ |
| 122 | MI_PRINT_SIMPLE_VALUES = PRINT_SIMPLE_VALUES, |
| 123 | |
| 124 | /* Print only scalar values for arguments when invoked from the CLI. */ |
| 125 | CLI_SCALAR_VALUES, |
| 126 | |
| 127 | /* Print all values for arguments when invoked from the CLI. */ |
| 128 | CLI_ALL_VALUES |
| 129 | }; |
| 130 | |
| 131 | /* The possible results of |
| 132 | extension_language_ops.breakpoint_cond_says_stop. */ |
| 133 | |
| 134 | enum ext_lang_bp_stop |
| 135 | { |
| 136 | /* No "stop" condition is set. */ |
| 137 | EXT_LANG_BP_STOP_UNSET, |
| 138 | |
| 139 | /* A "stop" condition is set, and it says "don't stop". */ |
| 140 | EXT_LANG_BP_STOP_NO, |
| 141 | |
| 142 | /* A "stop" condition is set, and it says "stop". */ |
| 143 | EXT_LANG_BP_STOP_YES |
| 144 | }; |
| 145 | |
| 146 | /* Table of type printers associated with the global typedef table. */ |
| 147 | |
| 148 | struct ext_lang_type_printers |
| 149 | { |
| 150 | ext_lang_type_printers (); |
| 151 | ~ext_lang_type_printers (); |
| 152 | |
| 153 | DISABLE_COPY_AND_ASSIGN (ext_lang_type_printers); |
| 154 | |
| 155 | /* Type-printers from Python. */ |
| 156 | void *py_type_printers = nullptr; |
| 157 | }; |
| 158 | |
| 159 | /* The return code for some API calls. */ |
| 160 | |
| 161 | enum ext_lang_rc |
| 162 | { |
| 163 | /* The operation completed successfully. */ |
| 164 | EXT_LANG_RC_OK, |
| 165 | |
| 166 | /* The operation was not performed (e.g., no pretty-printer). */ |
| 167 | EXT_LANG_RC_NOP, |
| 168 | |
| 169 | /* There was an error (e.g., Python error while printing a value). |
| 170 | When an error occurs no further extension languages are tried. |
| 171 | This is to preserve existing behaviour, and because it's convenient |
| 172 | for Python developers. |
| 173 | Note: This is different than encountering a memory error trying to read |
| 174 | a value for pretty-printing. Here we're referring to, e.g., programming |
| 175 | errors that trigger an exception in the extension language. */ |
| 176 | EXT_LANG_RC_ERROR |
| 177 | }; |
| 178 | |
| 179 | /* A type which holds its extension language specific xmethod worker data. */ |
| 180 | |
| 181 | struct xmethod_worker |
| 182 | { |
| 183 | xmethod_worker (const extension_language_defn *extlang) |
| 184 | : m_extlang (extlang) |
| 185 | {} |
| 186 | |
| 187 | virtual ~xmethod_worker () = default; |
| 188 | |
| 189 | /* Invoke the xmethod encapsulated in this worker and return the result. |
| 190 | The method is invoked on OBJ with arguments in the ARGS array. */ |
| 191 | |
| 192 | virtual value *invoke (value *obj, gdb::array_view<value *> args) = 0; |
| 193 | |
| 194 | /* Return the arg types of the xmethod encapsulated in this worker. |
| 195 | The type of the 'this' object is returned as the first element of |
| 196 | the vector. */ |
| 197 | |
| 198 | std::vector<type *> get_arg_types (); |
| 199 | |
| 200 | /* Return the type of the result of the xmethod encapsulated in this worker. |
| 201 | OBJECT and ARGS are the same as for invoke. */ |
| 202 | |
| 203 | type *get_result_type (value *object, gdb::array_view<value *> args); |
| 204 | |
| 205 | private: |
| 206 | |
| 207 | /* Return the types of the arguments the method takes. The types |
| 208 | are returned in TYPE_ARGS, one per argument. */ |
| 209 | |
| 210 | virtual enum ext_lang_rc do_get_arg_types |
| 211 | (std::vector<type *> *type_args) = 0; |
| 212 | |
| 213 | /* Fetch the type of the result of the method implemented by this |
| 214 | worker. OBJECT and ARGS are the same as for the invoked method. |
| 215 | The result type is stored in *RESULT_TYPE. */ |
| 216 | |
| 217 | virtual enum ext_lang_rc do_get_result_type |
| 218 | (struct value *obj, gdb::array_view<value *> args, |
| 219 | struct type **result_type_ptr) = 0; |
| 220 | |
| 221 | /* The language the xmethod worker is implemented in. */ |
| 222 | |
| 223 | const extension_language_defn *m_extlang; |
| 224 | }; |
| 225 | |
| 226 | typedef std::unique_ptr<xmethod_worker> xmethod_worker_up; |
| 227 | |
| 228 | /* The interface for gdb's own extension(/scripting) language. */ |
| 229 | extern const struct extension_language_defn extension_language_gdb; |
| 230 | |
| 231 | extern const struct extension_language_defn *get_ext_lang_defn |
| 232 | (enum extension_language lang); |
| 233 | |
| 234 | extern const struct extension_language_defn *get_ext_lang_of_file |
| 235 | (const char *file); |
| 236 | |
| 237 | extern int ext_lang_present_p (const struct extension_language_defn *); |
| 238 | |
| 239 | extern int ext_lang_initialized_p (const struct extension_language_defn *); |
| 240 | |
| 241 | extern void throw_ext_lang_unsupported |
| 242 | (const struct extension_language_defn *); |
| 243 | |
| 244 | /* Accessors for "public" attributes of the extension language definition. */ |
| 245 | |
| 246 | extern enum extension_language ext_lang_kind |
| 247 | (const struct extension_language_defn *); |
| 248 | |
| 249 | extern const char *ext_lang_name (const struct extension_language_defn *); |
| 250 | |
| 251 | extern const char *ext_lang_capitalized_name |
| 252 | (const struct extension_language_defn *); |
| 253 | |
| 254 | extern const char *ext_lang_suffix (const struct extension_language_defn *); |
| 255 | |
| 256 | extern const char *ext_lang_auto_load_suffix |
| 257 | (const struct extension_language_defn *); |
| 258 | |
| 259 | extern script_sourcer_func *ext_lang_script_sourcer |
| 260 | (const struct extension_language_defn *); |
| 261 | |
| 262 | extern objfile_script_sourcer_func *ext_lang_objfile_script_sourcer |
| 263 | (const struct extension_language_defn *); |
| 264 | |
| 265 | extern objfile_script_executor_func *ext_lang_objfile_script_executor |
| 266 | (const struct extension_language_defn *); |
| 267 | |
| 268 | extern int ext_lang_auto_load_enabled (const struct extension_language_defn *); |
| 269 | |
| 270 | /* Wrappers for each extension language API function that iterate over all |
| 271 | extension languages. */ |
| 272 | |
| 273 | extern void finish_ext_lang_initialization (void); |
| 274 | |
| 275 | extern void eval_ext_lang_from_control_command (struct command_line *cmd); |
| 276 | |
| 277 | extern void auto_load_ext_lang_scripts_for_objfile (struct objfile *); |
| 278 | |
| 279 | extern char *apply_ext_lang_type_printers (struct ext_lang_type_printers *, |
| 280 | struct type *); |
| 281 | |
| 282 | extern int apply_ext_lang_val_pretty_printer |
| 283 | (struct type *type, |
| 284 | LONGEST embedded_offset, CORE_ADDR address, |
| 285 | struct ui_file *stream, int recurse, |
| 286 | struct value *val, const struct value_print_options *options, |
| 287 | const struct language_defn *language); |
| 288 | |
| 289 | extern enum ext_lang_bt_status apply_ext_lang_frame_filter |
| 290 | (struct frame_info *frame, frame_filter_flags flags, |
| 291 | enum ext_lang_frame_args args_type, |
| 292 | struct ui_out *out, int frame_low, int frame_high); |
| 293 | |
| 294 | extern void preserve_ext_lang_values (struct objfile *, htab_t copied_types); |
| 295 | |
| 296 | extern const struct extension_language_defn *get_breakpoint_cond_ext_lang |
| 297 | (struct breakpoint *b, enum extension_language skip_lang); |
| 298 | |
| 299 | extern int breakpoint_ext_lang_cond_says_stop (struct breakpoint *); |
| 300 | |
| 301 | /* If a method with name METHOD_NAME is to be invoked on an object of type |
| 302 | TYPE, then all extension languages are searched for implementations of |
| 303 | methods with name METHOD_NAME. All matches found are appended to the WORKERS |
| 304 | vector. */ |
| 305 | |
| 306 | extern void get_matching_xmethod_workers |
| 307 | (struct type *type, const char *method_name, |
| 308 | std::vector<xmethod_worker_up> *workers); |
| 309 | |
| 310 | #endif /* EXTENSION_H */ |