gdb/top.h

   1 /* Top level stuff for GDB, the GNU debugger.
   2
   3    Copyright (C) 1986-2020 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 TOP_H
  21 #define TOP_H
  22
  23 #include "gdbsupport/buffer.h"
  24 #include "gdbsupport/event-loop.h"
  25 #include "gdbsupport/next-iterator.h"
  26 #include "value.h"
  27
  28 struct tl_interp_info;
  29
  30 /* Prompt state.  */
  31
  32 enum prompt_state
  33 {
  34   /* The command line is blocked simulating synchronous execution.
  35      This is used to implement the foreground execution commands
  36      ('run', 'continue', etc.).  We won't display the prompt and
  37      accept further commands until the execution is actually over.  */
  38   PROMPT_BLOCKED,
  39
  40   /* The command finished; display the prompt before returning back to
  41      the top level.  */
  42   PROMPT_NEEDED,
  43
  44   /* We've displayed the prompt already, ready for input.  */
  45   PROMPTED,
  46 };
  47
  48 /* All about a user interface instance.  Each user interface has its
  49    own I/O files/streams, readline state, its own top level
  50    interpreter (for the main UI, this is the interpreter specified
  51    with -i on the command line) and secondary interpreters (for
  52    interpreter-exec ...), etc.  There's always one UI associated with
  53    stdin/stdout/stderr, but the user can create secondary UIs, for
  54    example, to create a separate MI channel on its own stdio
  55    streams.  */
  56
  57 struct ui
  58 {
  59   /* Create a new UI.  */
  60   ui (FILE *instream, FILE *outstream, FILE *errstream);
  61   ~ui ();
  62
  63   DISABLE_COPY_AND_ASSIGN (ui);
  64
  65   /* Pointer to next in singly-linked list.  */
  66   struct ui *next;
  67
  68   /* The UI's command line buffer.  This is to used to accumulate
  69      input until we have a whole command line.  */
  70   struct buffer line_buffer;
  71
  72   /* The callback used by the event loop whenever an event is detected
  73      on the UI's input file descriptor.  This function incrementally
  74      builds a buffer where it accumulates the line read up to the
  75      point of invocation.  In the special case in which the character
  76      read is newline, the function invokes the INPUT_HANDLER callback
  77      (see below).  */
  78   void (*call_readline) (gdb_client_data);
  79
  80   /* The function to invoke when a complete line of input is ready for
  81      processing.  */
  82   void (*input_handler) (gdb::unique_xmalloc_ptr<char> &&);
  83
  84   /* True if this UI is using the readline library for command
  85      editing; false if using GDB's own simple readline emulation, with
  86      no editing support.  */
  87   int command_editing;
  88
  89   /* Each UI has its own independent set of interpreters.  */
  90   struct ui_interp_info *interp_info;
  91
  92   /* True if the UI is in async mode, false if in sync mode.  If in
  93      sync mode, a synchronous execution command (e.g, "next") does not
  94      return until the command is finished.  If in async mode, then
  95      running a synchronous command returns right after resuming the
  96      target.  Waiting for the command's completion is later done on
  97      the top event loop.  For the main UI, this starts out disabled,
  98      until all the explicit command line arguments (e.g., `gdb -ex
  99      "start" -ex "next"') are processed.  */
 100   int async;
 101
 102   /* The number of nested readline secondary prompts that are
 103      currently active.  */
 104   int secondary_prompt_depth;
 105
 106   /* The UI's stdin.  Set to stdin for the main UI.  */
 107   FILE *stdin_stream;
 108
 109   /* stdio stream that command input is being read from.  Set to stdin
 110      normally.  Set by source_command to the file we are sourcing.
 111      Set to NULL if we are executing a user-defined command or
 112      interacting via a GUI.  */
 113   FILE *instream;
 114   /* Standard output stream.  */
 115   FILE *outstream;
 116   /* Standard error stream.  */
 117   FILE *errstream;
 118
 119   /* The file descriptor for the input stream, so that we can register
 120      it with the event loop.  */
 121   int input_fd;
 122
 123   /* Whether ISATTY returns true on input_fd.  Cached here because
 124      quit_force needs to know this _after_ input_fd might be
 125      closed.  */
 126   int input_interactive_p;
 127
 128   /* See enum prompt_state's description.  */
 129   enum prompt_state prompt_state;
 130
 131   /* The fields below that start with "m_" are "private".  They're
 132      meant to be accessed through wrapper macros that make them look
 133      like globals.  */
 134
 135   /* The ui_file streams.  */
 136   /* Normal results */
 137   struct ui_file *m_gdb_stdout;
 138   /* Input stream */
 139   struct ui_file *m_gdb_stdin;
 140   /* Serious error notifications */
 141   struct ui_file *m_gdb_stderr;
 142   /* Log/debug/trace messages that should bypass normal stdout/stderr
 143      filtering.  For moment, always call this stream using
 144      *_unfiltered.  In the very near future that restriction shall be
 145      removed - either call shall be unfiltered.  (cagney 1999-06-13).  */
 146   struct ui_file *m_gdb_stdlog;
 147
 148   /* The current ui_out.  */
 149   struct ui_out *m_current_uiout;
 150 };
 151
 152 /* The main UI.  This is the UI that is bound to stdin/stdout/stderr.
 153    It always exists and is created automatically when GDB starts
 154    up.  */
 155 extern struct ui *main_ui;
 156
 157 /* The current UI.  */
 158 extern struct ui *current_ui;
 159
 160 /* The list of all UIs.  */
 161 extern struct ui *ui_list;
 162
 163 /* State for SWITCH_THRU_ALL_UIS.  */
 164 class switch_thru_all_uis
 165 {
 166 public:
 167
 168   switch_thru_all_uis () : m_iter (ui_list), m_save_ui (&current_ui)
 169   {
 170     current_ui = ui_list;
 171   }
 172
 173   /* If done iterating, return true; otherwise return false.  */
 174   bool done () const
 175   {
 176     return m_iter == NULL;
 177   }
 178
 179   /* Move to the next UI, setting current_ui if iteration is not yet
 180      complete.  */
 181   void next ()
 182   {
 183     m_iter = m_iter->next;
 184     if (m_iter != NULL)
 185       current_ui = m_iter;
 186   }
 187
 188  private:
 189
 190   /* No need for these.  They are intentionally not defined
 191      anywhere.  */
 192   switch_thru_all_uis &operator= (const switch_thru_all_uis &);
 193   switch_thru_all_uis (const switch_thru_all_uis &);
 194
 195   /* Used to iterate through the UIs.  */
 196   struct ui *m_iter;
 197
 198   /* Save and restore current_ui.  */
 199   scoped_restore_tmpl<struct ui *> m_save_ui;
 200 };
 201
 202   /* Traverse through all UI, and switch the current UI to the one
 203      being iterated.  */
 204 #define SWITCH_THRU_ALL_UIS()           \
 205   for (switch_thru_all_uis stau_state; !stau_state.done (); stau_state.next ())
 206
 207 /* An adapter that can be used to traverse over all UIs.  */
 208 static inline
 209 next_adapter<ui> all_uis ()
 210 {
 211   return next_adapter<ui> (ui_list);
 212 }
 213
 214 /* Register the UI's input file descriptor in the event loop.  */
 215 extern void ui_register_input_event_handler (struct ui *ui);
 216
 217 /* Unregister the UI's input file descriptor from the event loop.  */
 218 extern void ui_unregister_input_event_handler (struct ui *ui);
 219
 220 /* From top.c.  */
 221 extern bool confirm;
 222 extern int inhibit_gdbinit;
 223
 224 /* Print the GDB version banner to STREAM.  If INTERACTIVE is false,
 225    then information referring to commands (e.g., "show configuration")
 226    is omitted; this mode is used for the --version command line
 227    option.  If INTERACTIVE is true, then interactive commands are
 228    mentioned.  */
 229 extern void print_gdb_version (struct ui_file *stream, bool interactive);
 230
 231 extern void print_gdb_configuration (struct ui_file *);
 232
 233 extern void read_command_file (FILE *);
 234 extern void init_history (void);
 235 extern void command_loop (void);
 236 extern int quit_confirm (void);
 237 extern void quit_force (int *, int);
 238 extern void quit_command (const char *, int);
 239 extern void quit_cover (void);
 240 extern void execute_command (const char *, int);
 241
 242 /* If the interpreter is in sync mode (we're running a user command's
 243    list, running command hooks or similars), and we just ran a
 244    synchronous command that started the target, wait for that command
 245    to end.  WAS_SYNC indicates whether sync_execution was set before
 246    the command was run.  */
 247
 248 extern void maybe_wait_sync_command_done (int was_sync);
 249
 250 /* Wait for a synchronous execution command to end.  */
 251 extern void wait_sync_command_done (void);
 252
 253 extern void check_frame_language_change (void);
 254
 255 /* Prepare for execution of a command.
 256    Call this before every command, CLI or MI.
 257    Returns a cleanup to be run after the command is completed.  */
 258 extern scoped_value_mark prepare_execute_command (void);
 259
 260 /* This function returns a pointer to the string that is used
 261    by gdb for its command prompt.  */
 262 extern char *get_prompt (void);
 263
 264 /* This function returns a pointer to the string that is used
 265    by gdb for its command prompt.  */
 266 extern void set_prompt (const char *s);
 267
 268 /* Return 1 if UI's current input handler is a secondary prompt, 0
 269    otherwise.  */
 270
 271 extern int gdb_in_secondary_prompt_p (struct ui *ui);
 272
 273 /* From random places.  */
 274 extern int readnow_symbol_files;
 275 extern int readnever_symbol_files;
 276
 277 /* Perform _initialize initialization.  */
 278 extern void gdb_init (char *);
 279
 280 /* For use by event-top.c.  */
 281 /* Variables from top.c.  */
 282 extern int source_line_number;
 283 extern std::string source_file_name;
 284 extern bool history_expansion_p;
 285 extern bool server_command;
 286 extern char *lim_at_start;
 287
 288 extern void gdb_add_history (const char *);
 289
 290 extern void show_commands (const char *args, int from_tty);
 291
 292 extern void set_verbose (const char *, int, struct cmd_list_element *);
 293
 294 extern char *handle_line_of_input (struct buffer *cmd_line_buffer,
 295                                    const char *rl, int repeat,
 296                                    const char *annotation_suffix);
 297
 298 #endif