/* Define the fundamental Lisp data structures. */
-/* This is the set of Lisp data types. */
+/* This is the set of Lisp data types. If you want to define a new
+ data type, read the comments after Lisp_Fwd_Type definition
+ below. */
/* Lisp integers use 2 tags, to give them one extra bit, thus
extending their range from, e.g., -2^28..2^28-1 to -2^29..2^29-1. */
Lisp_Fwd_Kboard_Obj, /* Fwd to a Lisp_Object field of kboards. */
};
+/* If you want to define a new Lisp data type, here are some
+ instructions. See the thread at
+ http://lists.gnu.org/archive/html/emacs-devel/2012-10/msg00561.html
+ for more info.
+
+ First, there are already a couple of Lisp types that can be used if
+ your new type does not need to be exposed to Lisp programs nor
+ displayed to users. These are Lisp_Save_Value, a Lisp_Misc
+ subtype; and PVEC_OTHER, a kind of vectorlike object. The former
+ is suitable for temporarily stashing away pointers and integers in
+ a Lisp object (see the existing uses of make_save_value and
+ XSAVE_VALUE). The latter is useful for vector-like Lisp objects
+ that need to be used as part of other objects, but which are never
+ shown to users or Lisp code (search for PVEC_OTHER in xterm.c for
+ an example).
+
+ These two types don't look pretty when printed, so they are
+ unsuitable for Lisp objects that can be exposed to users.
+
+ To define a new data type, add one more Lisp_Misc subtype or one
+ more pseudovector subtype. Pseudovectors are more suitable for
+ objects with several slots that need to support fast random access,
+ while Lisp_Misc types are for everything else. A pseudovector object
+ provides one or more slots for Lisp objects, followed by struct
+ members that are accessible only from C. A Lisp_Misc object is a
+ wrapper for a C struct that can contain anything you like.
+
+ To add a new pseudovector type, extend the pvec_type enumeration;
+ to add a new Lisp_Misc, extend the Lisp_Misc_Type enumeration.
+
+ For a Lisp_Misc, you will also need to add your entry to union
+ Lisp_Misc (but make sure the first word has the same structure as
+ the others, starting with a 16-bit member of the Lisp_Misc_Type
+ enumeration and a 1-bit GC markbit) and make sure the overall size
+ of the union is not increased by your addition.
+
+ Then you will need to add switch branches in print.c (in
+ print_object, to print your object, and possibly also in
+ print_preprocess) and to alloc.c, to mark your object (in
+ mark_object) and to free it (in gc_sweep). The latter is also the
+ right place to call any code specific to your data type that needs
+ to run when the object is recycled -- e.g., free any additional
+ resources allocated for it that are not Lisp objects. You can even
+ make a pointer to the function that frees the resources a slot in
+ your object -- this way, the same object could be used to represent
+ several disparate C structures. */
+
#ifdef CHECK_LISP_OBJECT_TYPE
typedef struct { EMACS_INT i; } Lisp_Object;
= PSEUDOVECTOR_FLAG;
/* In a pseudovector, the size field actually contains a word with one
- PSEUDOVECTOR_FLAG bit set, and exactly one of the following bits to
- indicate the actual type.
- We use a bitset, even tho only one of the bits can be set at any
- particular time just so as to be able to use micro-optimizations such as
- testing membership of a particular subset of pseudovectors in Fequal.
- It is not crucial, but there are plenty of bits here, so why not do it? */
+ PSEUDOVECTOR_FLAG bit set, and one of the following values extracted
+ with PVEC_TYPE_MASK to indicate the actual type. */
enum pvec_type
{
- PVEC_NORMAL_VECTOR = 0, /* Unused! */
+ PVEC_NORMAL_VECTOR,
PVEC_FREE,
PVEC_PROCESS,
PVEC_FRAME,
struct backtrace
{
struct backtrace *next;
- Lisp_Object *function;
+ Lisp_Object function;
Lisp_Object *args; /* Points to vector of args. */
ptrdiff_t nargs; /* Length of vector. */
/* Nonzero means call value of debugger when done with this operation. */
a request to exit Emacs when it is safe to do. */
extern void process_pending_signals (void);
-extern int volatile pending_signals;
+extern bool volatile pending_signals;
extern void process_quit_flag (void);
#define QUIT \
} while (0)
extern int openp (Lisp_Object, Lisp_Object, Lisp_Object,
Lisp_Object *, Lisp_Object);
-Lisp_Object string_to_number (char const *, int, int);
+extern Lisp_Object string_to_number (char const *, int, bool);
extern void map_obarray (Lisp_Object, void (*) (Lisp_Object, Lisp_Object),
Lisp_Object);
extern void dir_warning (const char *, Lisp_Object);
extern Lisp_Object make_buffer_string_both (ptrdiff_t, ptrdiff_t, ptrdiff_t,
ptrdiff_t, bool);
extern void init_editfns (void);
-const char *get_system_name (void);
extern void syms_of_editfns (void);
extern void set_time_zone_rule (const char *);
extern void syms_of_fileio (void);
extern Lisp_Object make_temp_name (Lisp_Object, bool);
extern Lisp_Object Qdelete_file;
+extern bool check_existing (const char *);
/* Defined in search.c. */
extern void shrink_regexp_cache (void);
extern ptrdiff_t fast_looking_at (Lisp_Object, ptrdiff_t, ptrdiff_t,
ptrdiff_t, ptrdiff_t, Lisp_Object);
extern ptrdiff_t scan_buffer (int, ptrdiff_t, ptrdiff_t, ptrdiff_t,
- ptrdiff_t *, int);
+ ptrdiff_t *, bool);
extern EMACS_INT scan_newline (ptrdiff_t, ptrdiff_t, ptrdiff_t, ptrdiff_t,
- EMACS_INT, int);
+ EMACS_INT, bool);
extern ptrdiff_t find_next_newline (ptrdiff_t, int);
extern ptrdiff_t find_next_newline_no_quit (ptrdiff_t, ptrdiff_t);
extern ptrdiff_t find_before_next_newline (ptrdiff_t, ptrdiff_t, ptrdiff_t);
extern Lisp_Object Qup, Qdown, Qbottom;
extern Lisp_Object Qtop;
extern Lisp_Object last_undo_boundary;
-extern int input_pending;
+extern bool input_pending;
extern Lisp_Object menu_bar_items (Lisp_Object);
extern Lisp_Object tool_bar_items (Lisp_Object, int *);
extern void discard_mouse_events (void);
void handle_input_available_signal (int);
#endif
extern Lisp_Object pending_funcalls;
-extern int detect_input_pending (void);
-extern int detect_input_pending_ignore_squeezables (void);
-extern int detect_input_pending_run_timers (int);
+extern bool detect_input_pending (void);
+extern bool detect_input_pending_ignore_squeezables (void);
+extern bool detect_input_pending_run_timers (bool);
extern void safe_run_hooks (Lisp_Object);
extern void cmd_error_internal (Lisp_Object, const char *);
extern Lisp_Object command_loop_1 (void);
extern Lisp_Object QCtype, Qlocal;
extern Lisp_Object Qprocessp;
extern void kill_buffer_processes (Lisp_Object);
-extern int wait_reading_process_output (intmax_t, int, int, int,
+extern int wait_reading_process_output (intmax_t, int, int, bool,
Lisp_Object,
struct Lisp_Process *,
int);
extern char *get_current_dir_name (void);
#endif
extern void stuff_char (char c);
+extern void init_foreground_group (void);
extern void init_sigio (int);
extern void sys_subshell (void);
extern void sys_suspend (void);
Used during startup to detect startup of dumped Emacs. */
extern bool initialized;
-extern int immediate_quit; /* Nonzero means ^G can quit instantly. */
+/* True means ^G can quit instantly. */
+extern bool immediate_quit;
extern void *xmalloc (size_t);
extern void *xzalloc (size_t);