mirror of
https://git.savannah.gnu.org/git/emacs.git
synced 2024-11-23 07:19:15 +00:00
1644 lines
52 KiB
C
1644 lines
52 KiB
C
/* emacs-module.c - Module loading and runtime implementation
|
||
|
||
Copyright (C) 2015-2023 Free Software Foundation, Inc.
|
||
|
||
This file is part of GNU Emacs.
|
||
|
||
GNU Emacs 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.
|
||
|
||
GNU Emacs 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 GNU Emacs. If not, see <https://www.gnu.org/licenses/>. */
|
||
|
||
/*
|
||
The public module API is defined in the header emacs-module.h. The
|
||
configure script generates emacs-module.h from emacs-module.h.in and
|
||
the version-specific environment fragments in module-env-*.h.
|
||
|
||
If you want to change the module API, please abide to the following
|
||
rules:
|
||
|
||
- Don't remove publicly documented declarations from the headers.
|
||
|
||
- Don't remove, reorder, or rename structure fields, as such changes
|
||
break ABI compatibility.
|
||
|
||
- Don't change the types of structure fields.
|
||
|
||
- Likewise, the presence, order, and type of structure fields may not
|
||
depend on preprocessor macros.
|
||
|
||
- Add structure fields only at the end of structures.
|
||
|
||
- For every Emacs major version there is a new fragment file
|
||
module-env-VER.h. Add functions solely at the end of the fragment
|
||
file for the next (not yet released) major version of Emacs. For
|
||
example, if the current Emacs release is 26.2, add functions only to
|
||
module-env-27.h.
|
||
|
||
- emacs-module.h should only depend on standard C headers. In
|
||
particular, don't include config.h or lisp.h from emacs-module.h.
|
||
|
||
- The contents of emacs-module.h should be the same on all platforms
|
||
and architectures.
|
||
|
||
- emacs-module.h may not depend on Emacs configuration options.
|
||
|
||
- Prefix all names in emacs-module.h with "emacs_" or "EMACS_".
|
||
|
||
To add a new module function, proceed as follows:
|
||
|
||
1. Add a new function pointer field at the end of the module-env-*.h
|
||
file for the next major version of Emacs.
|
||
|
||
2. Run config.status or configure to regenerate emacs-module.h.
|
||
|
||
3. Create a corresponding implementation function in this file. See
|
||
"Implementation of runtime and environment functions" below for
|
||
further rules.
|
||
|
||
4. Assign the new field in the initialize_environment function.
|
||
|
||
5. Add a test function that calls your new function to
|
||
test/data/emacs-module/mod-test.c. Add a unit test that invokes
|
||
your new test function to test/src/emacs-module-tests.el.
|
||
|
||
6. Document your new function in the manual and in etc/NEWS.
|
||
*/
|
||
|
||
#include <config.h>
|
||
|
||
#include "emacs-module.h"
|
||
|
||
#include <stdarg.h>
|
||
#include <stddef.h>
|
||
#include <stdint.h>
|
||
#include <stdlib.h>
|
||
#include <time.h>
|
||
|
||
#include "lisp.h"
|
||
#include "bignum.h"
|
||
#include "dynlib.h"
|
||
#include "coding.h"
|
||
#include "keyboard.h"
|
||
#include "process.h"
|
||
#include "syssignal.h"
|
||
#include "sysstdio.h"
|
||
#include "thread.h"
|
||
|
||
#include <intprops.h>
|
||
#include <verify.h>
|
||
|
||
/* Work around GCC bug 83162. */
|
||
#if GNUC_PREREQ (4, 3, 0)
|
||
# pragma GCC diagnostic ignored "-Wclobbered"
|
||
#endif
|
||
|
||
/* We use different strategies for allocating the user-visible objects
|
||
(struct emacs_runtime, emacs_env, emacs_value), depending on
|
||
whether the user supplied the -module-assertions flag. If
|
||
assertions are disabled, all objects are allocated from the stack.
|
||
If assertions are enabled, all objects are allocated from the free
|
||
store, and objects are never freed; this guarantees that they all
|
||
have different addresses. We use that for checking which objects
|
||
are live. Without unique addresses, we might consider some dead
|
||
objects live because their addresses would have been reused in the
|
||
meantime. */
|
||
|
||
|
||
/* Feature tests. */
|
||
|
||
#ifdef WINDOWSNT
|
||
#include <windows.h>
|
||
#include "w32term.h"
|
||
#endif
|
||
|
||
/* Function prototype for the module init function. */
|
||
typedef int (*emacs_init_function) (struct emacs_runtime *);
|
||
|
||
|
||
/* Memory management. */
|
||
|
||
/* An `emacs_value' is just a pointer to a structure holding an
|
||
internal Lisp object. */
|
||
struct emacs_value_tag { Lisp_Object v; };
|
||
|
||
/* Local value objects use a simple fixed-sized block allocation
|
||
scheme without explicit deallocation. All local values are
|
||
deallocated when the lifetime of their environment ends. Keep
|
||
track of a current frame from which new values are allocated,
|
||
appending further dynamically-allocated frames if necessary. */
|
||
|
||
enum { value_frame_size = 512 };
|
||
|
||
/* A block from which `emacs_value' object can be allocated. */
|
||
struct emacs_value_frame
|
||
{
|
||
/* Storage for values. */
|
||
struct emacs_value_tag objects[value_frame_size];
|
||
|
||
/* Index of the next free value in `objects'. */
|
||
int offset;
|
||
|
||
/* Pointer to next frame, if any. */
|
||
struct emacs_value_frame *next;
|
||
};
|
||
|
||
/* A structure that holds an initial frame (so that the first local
|
||
values require no dynamic allocation) and keeps track of the
|
||
current frame. */
|
||
struct emacs_value_storage
|
||
{
|
||
struct emacs_value_frame initial;
|
||
struct emacs_value_frame *current;
|
||
};
|
||
|
||
|
||
/* Private runtime and environment members. */
|
||
|
||
/* The private part of an environment stores the current non local exit state
|
||
and holds the `emacs_value' objects allocated during the lifetime
|
||
of the environment. */
|
||
struct emacs_env_private
|
||
{
|
||
enum emacs_funcall_exit pending_non_local_exit;
|
||
|
||
/* Dedicated storage for non-local exit symbol and data so that
|
||
storage is always available for them, even in an out-of-memory
|
||
situation. */
|
||
struct emacs_value_tag non_local_exit_symbol, non_local_exit_data;
|
||
|
||
struct emacs_value_storage storage;
|
||
};
|
||
|
||
/* The private parts of an `emacs_runtime' object contain the initial
|
||
environment. */
|
||
struct emacs_runtime_private
|
||
{
|
||
emacs_env *env;
|
||
};
|
||
|
||
|
||
/* Forward declarations. */
|
||
|
||
static Lisp_Object value_to_lisp (emacs_value);
|
||
static emacs_value allocate_emacs_value (emacs_env *, Lisp_Object);
|
||
static emacs_value lisp_to_value (emacs_env *, Lisp_Object);
|
||
static enum emacs_funcall_exit module_non_local_exit_check (emacs_env *);
|
||
static void module_assert_thread (void);
|
||
static void module_assert_runtime (struct emacs_runtime *);
|
||
static void module_assert_env (emacs_env *);
|
||
static AVOID module_abort (const char *, ...) ATTRIBUTE_FORMAT_PRINTF (1, 2);
|
||
static emacs_env *initialize_environment (emacs_env *,
|
||
struct emacs_env_private *);
|
||
static void finalize_environment (emacs_env *);
|
||
static void module_handle_nonlocal_exit (emacs_env *, enum nonlocal_exit,
|
||
Lisp_Object);
|
||
static void module_non_local_exit_signal_1 (emacs_env *,
|
||
Lisp_Object, Lisp_Object);
|
||
static void module_non_local_exit_throw_1 (emacs_env *,
|
||
Lisp_Object, Lisp_Object);
|
||
static void module_out_of_memory (emacs_env *);
|
||
static void module_reset_handlerlist (struct handler **);
|
||
static bool value_storage_contains_p (const struct emacs_value_storage *,
|
||
emacs_value, ptrdiff_t *);
|
||
|
||
static bool module_assertions = false;
|
||
|
||
|
||
/* Small helper functions. */
|
||
|
||
/* Interprets the string at STR with length LEN as UTF-8 string.
|
||
Signals an error if it's not a valid UTF-8 string. */
|
||
|
||
static Lisp_Object
|
||
module_decode_utf_8 (const char *str, ptrdiff_t len)
|
||
{
|
||
/* We set HANDLE-8-BIT and HANDLE-OVER-UNI to nil to signal an error
|
||
if the argument is not a valid UTF-8 string. While it isn't
|
||
documented how make_string and make_function behave in this case,
|
||
signaling an error is the most defensive and obvious reaction. */
|
||
Lisp_Object s = decode_string_utf_8 (Qnil, str, len, Qnil, false, Qnil, Qnil);
|
||
CHECK_TYPE (!NILP (s), Qutf_8_string_p, make_string_from_utf8 (str, len));
|
||
return s;
|
||
}
|
||
|
||
|
||
/* Convenience macros for non-local exit handling. */
|
||
|
||
/* FIXME: The following implementation for non-local exit handling
|
||
does not support recovery from stack overflow, see sysdep.c. */
|
||
|
||
/* Emacs uses setjmp and longjmp for non-local exits, but
|
||
module frames cannot be skipped because they are in general
|
||
not prepared for long jumps (e.g., the behavior in C++ is undefined
|
||
if objects with nontrivial destructors would be skipped).
|
||
Therefore, catch all non-local exits. There are two kinds of
|
||
non-local exits: `signal' and `throw'. The macro in this section
|
||
can be used to catch both. Use a macro to avoid additional variants
|
||
of `internal_condition_case' etc., and to avoid worrying about
|
||
passing information to the handler functions. */
|
||
|
||
#if !HAS_ATTRIBUTE (cleanup)
|
||
#error "__attribute__ ((cleanup)) not supported by this compiler; try GCC"
|
||
#endif
|
||
|
||
/* Place this macro at the beginning of a function returning a number
|
||
or a pointer to handle non-local exits. The function must have an
|
||
ENV parameter. The function will return the specified value if a
|
||
signal or throw is caught. */
|
||
|
||
/* It is very important that pushing the handler doesn't itself raise
|
||
a signal. Install the cleanup only after the handler has been
|
||
pushed. Use __attribute__ ((cleanup)) to avoid
|
||
non-local-exit-prone manual cleanup.
|
||
|
||
The do-while forces uses of the macro to be followed by a semicolon.
|
||
This macro cannot enclose its entire body inside a do-while, as the
|
||
code after the macro may longjmp back into the macro, which means
|
||
its local variable INTERNAL_CLEANUP must stay live in later code. */
|
||
|
||
/* TODO: Make backtraces work if this macro is used. */
|
||
|
||
#define MODULE_HANDLE_NONLOCAL_EXIT(retval) \
|
||
if (module_non_local_exit_check (env) != emacs_funcall_exit_return) \
|
||
return retval; \
|
||
struct handler *internal_handler = \
|
||
push_handler_nosignal (Qt, CATCHER_ALL); \
|
||
if (!internal_handler) \
|
||
{ \
|
||
module_out_of_memory (env); \
|
||
return retval; \
|
||
} \
|
||
struct handler *internal_cleanup \
|
||
__attribute__ ((cleanup (module_reset_handlerlist))) \
|
||
= internal_handler; \
|
||
if (sys_setjmp (internal_cleanup->jmp)) \
|
||
{ \
|
||
module_handle_nonlocal_exit (env, \
|
||
internal_cleanup->nonlocal_exit, \
|
||
internal_cleanup->val); \
|
||
return retval; \
|
||
} \
|
||
do { } while (false)
|
||
|
||
|
||
/* Implementation of runtime and environment functions.
|
||
|
||
These should abide by the following rules:
|
||
|
||
1. The first argument should always be a pointer to emacs_env.
|
||
|
||
2. Each function should first call check_thread. Note that
|
||
this function is a no-op unless Emacs was built with
|
||
--enable-checking.
|
||
|
||
3. The very next thing each function should do is check that the
|
||
emacs_env object does not have a non-local exit indication set,
|
||
by calling module_non_local_exit_check. If that returns
|
||
anything but emacs_funcall_exit_return, the function should do
|
||
nothing and return immediately with an error indication, without
|
||
clobbering the existing error indication in emacs_env. This is
|
||
needed for correct reporting of Lisp errors to the Emacs Lisp
|
||
interpreter.
|
||
|
||
4. Any function that needs to call Emacs facilities, such as
|
||
encoding or decoding functions, or 'intern', or 'make_string',
|
||
should protect itself from signals and 'throw' in the called
|
||
Emacs functions, by placing the macro
|
||
MODULE_HANDLE_NONLOCAL_EXIT right after the above 2 tests.
|
||
|
||
5. Do NOT use 'eassert' for checking validity of user code in the
|
||
module. Instead, make those checks part of the code, and if the
|
||
check fails, call 'module_non_local_exit_signal_1' or
|
||
'module_non_local_exit_throw_1' to report the error. This is
|
||
because using 'eassert' in these situations will abort Emacs
|
||
instead of reporting the error back to Lisp, and also because
|
||
'eassert' is compiled to nothing in the release version. */
|
||
|
||
/* Use MODULE_FUNCTION_BEGIN_NO_CATCH to implement steps 2 and 3 for
|
||
environment functions that are known to never exit non-locally. On
|
||
error it will return its argument, which can be a sentinel
|
||
value. */
|
||
|
||
#define MODULE_FUNCTION_BEGIN_NO_CATCH(error_retval) \
|
||
do { \
|
||
module_assert_thread (); \
|
||
module_assert_env (env); \
|
||
if (module_non_local_exit_check (env) != emacs_funcall_exit_return) \
|
||
return error_retval; \
|
||
} while (false)
|
||
|
||
/* Use MODULE_FUNCTION_BEGIN to implement steps 2 through 4 for most
|
||
environment functions. On error it will return its argument, which
|
||
can be a sentinel value. */
|
||
|
||
#define MODULE_FUNCTION_BEGIN(error_retval) \
|
||
MODULE_FUNCTION_BEGIN_NO_CATCH (error_retval); \
|
||
MODULE_HANDLE_NONLOCAL_EXIT (error_retval)
|
||
|
||
static void
|
||
CHECK_MODULE_FUNCTION (Lisp_Object obj)
|
||
{
|
||
CHECK_TYPE (MODULE_FUNCTIONP (obj), Qmodule_function_p, obj);
|
||
}
|
||
|
||
static void
|
||
CHECK_USER_PTR (Lisp_Object obj)
|
||
{
|
||
CHECK_TYPE (USER_PTRP (obj), Quser_ptrp, obj);
|
||
}
|
||
|
||
/* Catch signals and throws only if the code can actually signal or
|
||
throw. If checking is enabled, abort if the current thread is not
|
||
the Emacs main thread. */
|
||
|
||
static emacs_env *
|
||
module_get_environment (struct emacs_runtime *runtime)
|
||
{
|
||
module_assert_thread ();
|
||
module_assert_runtime (runtime);
|
||
return runtime->private_members->env;
|
||
}
|
||
|
||
/* To make global refs (GC-protected global values) keep a hash that
|
||
maps global Lisp objects to 'struct module_global_reference'
|
||
objects. We store the 'emacs_value' in the hash table so that it
|
||
is automatically garbage-collected (Bug#42482). */
|
||
|
||
static Lisp_Object Vmodule_refs_hash;
|
||
|
||
/* Pseudovector type for global references. The pseudovector tag is
|
||
PVEC_OTHER since these values are never printed and don't need to
|
||
be special-cased for garbage collection. */
|
||
|
||
struct module_global_reference {
|
||
/* Pseudovector header, must come first. */
|
||
union vectorlike_header header;
|
||
|
||
/* Holds the emacs_value for the object. The Lisp_Object stored
|
||
therein must be the same as the hash key. */
|
||
struct emacs_value_tag value;
|
||
|
||
/* Reference count, always positive. */
|
||
ptrdiff_t refcount;
|
||
};
|
||
|
||
static struct module_global_reference *
|
||
XMODULE_GLOBAL_REFERENCE (Lisp_Object o)
|
||
{
|
||
eassert (PSEUDOVECTORP (o, PVEC_OTHER));
|
||
return XUNTAG (o, Lisp_Vectorlike, struct module_global_reference);
|
||
}
|
||
|
||
/* Returns whether V is a global reference. Only used to check module
|
||
assertions. If V is not a global reference, increment *N by the
|
||
number of global references (for debugging output). */
|
||
|
||
static bool
|
||
module_global_reference_p (emacs_value v, ptrdiff_t *n)
|
||
{
|
||
struct Lisp_Hash_Table *h = XHASH_TABLE (Vmodule_refs_hash);
|
||
/* Note that we can't use `hash_lookup' because V might be a local
|
||
reference that's identical to some global reference. */
|
||
for (ptrdiff_t i = 0; i < HASH_TABLE_SIZE (h); ++i)
|
||
{
|
||
if (!BASE_EQ (HASH_KEY (h, i), Qunbound)
|
||
&& &XMODULE_GLOBAL_REFERENCE (HASH_VALUE (h, i))->value == v)
|
||
return true;
|
||
}
|
||
/* Only used for debugging, so we don't care about overflow, just
|
||
make sure the operation is defined. */
|
||
INT_ADD_WRAPV (*n, h->count, n);
|
||
return false;
|
||
}
|
||
|
||
static emacs_value
|
||
module_make_global_ref (emacs_env *env, emacs_value value)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
struct Lisp_Hash_Table *h = XHASH_TABLE (Vmodule_refs_hash);
|
||
Lisp_Object new_obj = value_to_lisp (value), hashcode;
|
||
ptrdiff_t i = hash_lookup (h, new_obj, &hashcode);
|
||
|
||
/* Note: This approach requires the garbage collector to never move
|
||
objects. */
|
||
|
||
if (i >= 0)
|
||
{
|
||
Lisp_Object value = HASH_VALUE (h, i);
|
||
struct module_global_reference *ref = XMODULE_GLOBAL_REFERENCE (value);
|
||
bool overflow = INT_ADD_WRAPV (ref->refcount, 1, &ref->refcount);
|
||
if (overflow)
|
||
overflow_error ();
|
||
return &ref->value;
|
||
}
|
||
else
|
||
{
|
||
struct module_global_reference *ref
|
||
= ALLOCATE_PLAIN_PSEUDOVECTOR (struct module_global_reference,
|
||
PVEC_OTHER);
|
||
ref->value.v = new_obj;
|
||
ref->refcount = 1;
|
||
Lisp_Object value;
|
||
XSETPSEUDOVECTOR (value, ref, PVEC_OTHER);
|
||
hash_put (h, new_obj, value, hashcode);
|
||
return &ref->value;
|
||
}
|
||
}
|
||
|
||
static void
|
||
module_free_global_ref (emacs_env *env, emacs_value global_value)
|
||
{
|
||
/* TODO: This probably never signals. */
|
||
/* FIXME: Wait a minute. Shouldn't this function report an error if
|
||
the hash lookup fails? */
|
||
MODULE_FUNCTION_BEGIN ();
|
||
struct Lisp_Hash_Table *h = XHASH_TABLE (Vmodule_refs_hash);
|
||
Lisp_Object obj = value_to_lisp (global_value);
|
||
ptrdiff_t i = hash_lookup (h, obj, NULL);
|
||
|
||
if (module_assertions)
|
||
{
|
||
ptrdiff_t n = 0;
|
||
if (! module_global_reference_p (global_value, &n))
|
||
module_abort ("Global value was not found in list of %"pD"d globals",
|
||
n);
|
||
}
|
||
|
||
if (i >= 0)
|
||
{
|
||
Lisp_Object value = HASH_VALUE (h, i);
|
||
struct module_global_reference *ref = XMODULE_GLOBAL_REFERENCE (value);
|
||
eassert (0 < ref->refcount);
|
||
if (--ref->refcount == 0)
|
||
hash_remove_from_table (h, obj);
|
||
}
|
||
}
|
||
|
||
static enum emacs_funcall_exit
|
||
module_non_local_exit_check (emacs_env *env)
|
||
{
|
||
module_assert_thread ();
|
||
module_assert_env (env);
|
||
return env->private_members->pending_non_local_exit;
|
||
}
|
||
|
||
static void
|
||
module_non_local_exit_clear (emacs_env *env)
|
||
{
|
||
module_assert_thread ();
|
||
module_assert_env (env);
|
||
env->private_members->pending_non_local_exit = emacs_funcall_exit_return;
|
||
}
|
||
|
||
static enum emacs_funcall_exit
|
||
module_non_local_exit_get (emacs_env *env,
|
||
emacs_value *symbol, emacs_value *data)
|
||
{
|
||
module_assert_thread ();
|
||
module_assert_env (env);
|
||
struct emacs_env_private *p = env->private_members;
|
||
if (p->pending_non_local_exit != emacs_funcall_exit_return)
|
||
{
|
||
*symbol = &p->non_local_exit_symbol;
|
||
*data = &p->non_local_exit_data;
|
||
}
|
||
return p->pending_non_local_exit;
|
||
}
|
||
|
||
/* Like for `signal', DATA must be a list. */
|
||
static void
|
||
module_non_local_exit_signal (emacs_env *env,
|
||
emacs_value symbol, emacs_value data)
|
||
{
|
||
module_assert_thread ();
|
||
module_assert_env (env);
|
||
if (module_non_local_exit_check (env) == emacs_funcall_exit_return)
|
||
module_non_local_exit_signal_1 (env, value_to_lisp (symbol),
|
||
value_to_lisp (data));
|
||
}
|
||
|
||
static void
|
||
module_non_local_exit_throw (emacs_env *env, emacs_value tag, emacs_value value)
|
||
{
|
||
module_assert_thread ();
|
||
module_assert_env (env);
|
||
if (module_non_local_exit_check (env) == emacs_funcall_exit_return)
|
||
module_non_local_exit_throw_1 (env, value_to_lisp (tag),
|
||
value_to_lisp (value));
|
||
}
|
||
|
||
/* Module function. */
|
||
|
||
/* A function environment is an auxiliary structure returned by
|
||
`module_make_function' to store information about a module
|
||
function. It is stored in a pseudovector. Its members correspond
|
||
to the arguments given to `module_make_function'. */
|
||
|
||
struct Lisp_Module_Function
|
||
{
|
||
union vectorlike_header header;
|
||
|
||
/* Fields traced by GC; these must come first. */
|
||
Lisp_Object documentation, interactive_form, command_modes;
|
||
|
||
/* Fields ignored by GC. */
|
||
ptrdiff_t min_arity, max_arity;
|
||
emacs_function subr;
|
||
void *data;
|
||
emacs_finalizer finalizer;
|
||
} GCALIGNED_STRUCT;
|
||
|
||
static struct Lisp_Module_Function *
|
||
allocate_module_function (void)
|
||
{
|
||
return ALLOCATE_PSEUDOVECTOR (struct Lisp_Module_Function,
|
||
command_modes, PVEC_MODULE_FUNCTION);
|
||
}
|
||
|
||
#define XSET_MODULE_FUNCTION(var, ptr) \
|
||
XSETPSEUDOVECTOR (var, ptr, PVEC_MODULE_FUNCTION)
|
||
|
||
/* A module function is a pseudovector of subtype
|
||
PVEC_MODULE_FUNCTION; see lisp.h for the definition. */
|
||
|
||
static emacs_value
|
||
module_make_function (emacs_env *env, ptrdiff_t min_arity, ptrdiff_t max_arity,
|
||
emacs_function func, const char *docstring, void *data)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
|
||
if (! (0 <= min_arity
|
||
&& (max_arity < 0
|
||
? (min_arity <= MOST_POSITIVE_FIXNUM
|
||
&& max_arity == emacs_variadic_function)
|
||
: min_arity <= max_arity && max_arity <= MOST_POSITIVE_FIXNUM)))
|
||
xsignal2 (Qinvalid_arity, make_fixnum (min_arity), make_fixnum (max_arity));
|
||
|
||
struct Lisp_Module_Function *function = allocate_module_function ();
|
||
function->min_arity = min_arity;
|
||
function->max_arity = max_arity;
|
||
function->subr = func;
|
||
function->data = data;
|
||
function->finalizer = NULL;
|
||
|
||
if (docstring)
|
||
function->documentation
|
||
= module_decode_utf_8 (docstring, strlen (docstring));
|
||
|
||
Lisp_Object result;
|
||
XSET_MODULE_FUNCTION (result, function);
|
||
eassert (MODULE_FUNCTIONP (result));
|
||
|
||
return lisp_to_value (env, result);
|
||
}
|
||
|
||
static emacs_finalizer
|
||
module_get_function_finalizer (emacs_env *env, emacs_value arg)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
Lisp_Object lisp = value_to_lisp (arg);
|
||
CHECK_MODULE_FUNCTION (lisp);
|
||
return XMODULE_FUNCTION (lisp)->finalizer;
|
||
}
|
||
|
||
static void
|
||
module_set_function_finalizer (emacs_env *env, emacs_value arg,
|
||
emacs_finalizer fin)
|
||
{
|
||
MODULE_FUNCTION_BEGIN ();
|
||
Lisp_Object lisp = value_to_lisp (arg);
|
||
CHECK_MODULE_FUNCTION (lisp);
|
||
XMODULE_FUNCTION (lisp)->finalizer = fin;
|
||
}
|
||
|
||
void
|
||
module_finalize_function (const struct Lisp_Module_Function *func)
|
||
{
|
||
if (func->finalizer != NULL)
|
||
func->finalizer (func->data);
|
||
}
|
||
|
||
static void
|
||
module_make_interactive (emacs_env *env, emacs_value function, emacs_value spec)
|
||
{
|
||
MODULE_FUNCTION_BEGIN ();
|
||
Lisp_Object lisp_fun = value_to_lisp (function);
|
||
CHECK_MODULE_FUNCTION (lisp_fun);
|
||
Lisp_Object lisp_spec = value_to_lisp (spec);
|
||
/* Normalize (interactive nil) to (interactive). */
|
||
XMODULE_FUNCTION (lisp_fun)->interactive_form
|
||
= NILP (lisp_spec) ? list1 (Qinteractive) : list2 (Qinteractive, lisp_spec);
|
||
}
|
||
|
||
Lisp_Object
|
||
module_function_interactive_form (const struct Lisp_Module_Function *fun)
|
||
{
|
||
return fun->interactive_form;
|
||
}
|
||
|
||
Lisp_Object
|
||
module_function_command_modes (const struct Lisp_Module_Function *fun)
|
||
{
|
||
return fun->command_modes;
|
||
}
|
||
|
||
static emacs_value
|
||
module_funcall (emacs_env *env, emacs_value func, ptrdiff_t nargs,
|
||
emacs_value *args)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
|
||
/* Make a new Lisp_Object array starting with the function as the
|
||
first arg, because that's what Ffuncall takes. */
|
||
Lisp_Object *newargs;
|
||
USE_SAFE_ALLOCA;
|
||
ptrdiff_t nargs1;
|
||
if (INT_ADD_WRAPV (nargs, 1, &nargs1))
|
||
overflow_error ();
|
||
SAFE_ALLOCA_LISP (newargs, nargs1);
|
||
newargs[0] = value_to_lisp (func);
|
||
for (ptrdiff_t i = 0; i < nargs; i++)
|
||
newargs[1 + i] = value_to_lisp (args[i]);
|
||
emacs_value result = lisp_to_value (env, Ffuncall (nargs1, newargs));
|
||
SAFE_FREE ();
|
||
return result;
|
||
}
|
||
|
||
static emacs_value
|
||
module_intern (emacs_env *env, const char *name)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
return lisp_to_value (env, intern (name));
|
||
}
|
||
|
||
static emacs_value
|
||
module_type_of (emacs_env *env, emacs_value arg)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
return lisp_to_value (env, Ftype_of (value_to_lisp (arg)));
|
||
}
|
||
|
||
static bool
|
||
module_is_not_nil (emacs_env *env, emacs_value arg)
|
||
{
|
||
MODULE_FUNCTION_BEGIN_NO_CATCH (false);
|
||
return ! NILP (value_to_lisp (arg));
|
||
}
|
||
|
||
static bool
|
||
module_eq (emacs_env *env, emacs_value a, emacs_value b)
|
||
{
|
||
MODULE_FUNCTION_BEGIN_NO_CATCH (false);
|
||
return EQ (value_to_lisp (a), value_to_lisp (b));
|
||
}
|
||
|
||
static intmax_t
|
||
module_extract_integer (emacs_env *env, emacs_value arg)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (0);
|
||
Lisp_Object lisp = value_to_lisp (arg);
|
||
CHECK_INTEGER (lisp);
|
||
intmax_t i;
|
||
if (! integer_to_intmax (lisp, &i))
|
||
xsignal1 (Qoverflow_error, lisp);
|
||
return i;
|
||
}
|
||
|
||
static emacs_value
|
||
module_make_integer (emacs_env *env, intmax_t n)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
return lisp_to_value (env, make_int (n));
|
||
}
|
||
|
||
static double
|
||
module_extract_float (emacs_env *env, emacs_value arg)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (0);
|
||
Lisp_Object lisp = value_to_lisp (arg);
|
||
CHECK_TYPE (FLOATP (lisp), Qfloatp, lisp);
|
||
return XFLOAT_DATA (lisp);
|
||
}
|
||
|
||
static emacs_value
|
||
module_make_float (emacs_env *env, double d)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
return lisp_to_value (env, make_float (d));
|
||
}
|
||
|
||
static bool
|
||
module_copy_string_contents (emacs_env *env, emacs_value value, char *buf,
|
||
ptrdiff_t *len)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (false);
|
||
Lisp_Object lisp_str = value_to_lisp (value);
|
||
CHECK_STRING (lisp_str);
|
||
|
||
/* We can set NOCOPY to true here because we only use the byte
|
||
sequence starting at SDATA and don't modify the original string
|
||
before copying out the data.
|
||
|
||
We set HANDLE-8-BIT and HANDLE-OVER-UNI to nil to signal an error
|
||
if the argument is not a valid Unicode string. While it isn't
|
||
documented how copy_string_contents behaves in this case,
|
||
signaling an error is the most defensive and obvious reaction. */
|
||
Lisp_Object lisp_str_utf8
|
||
= encode_string_utf_8 (lisp_str, Qnil, true, Qnil, Qnil);
|
||
|
||
/* Since we set HANDLE-8-BIT and HANDLE-OVER-UNI to nil, the return
|
||
value can be nil, and we have to check for that. */
|
||
CHECK_TYPE (!NILP (lisp_str_utf8), Qunicode_string_p, lisp_str);
|
||
|
||
ptrdiff_t raw_size = SBYTES (lisp_str_utf8);
|
||
ptrdiff_t required_buf_size = raw_size + 1;
|
||
|
||
if (buf == NULL)
|
||
{
|
||
*len = required_buf_size;
|
||
return true;
|
||
}
|
||
|
||
if (*len < required_buf_size)
|
||
{
|
||
ptrdiff_t actual = *len;
|
||
*len = required_buf_size;
|
||
args_out_of_range_3 (INT_TO_INTEGER (actual),
|
||
INT_TO_INTEGER (required_buf_size),
|
||
INT_TO_INTEGER (PTRDIFF_MAX));
|
||
}
|
||
|
||
*len = required_buf_size;
|
||
memcpy (buf, SDATA (lisp_str_utf8), raw_size + 1);
|
||
|
||
return true;
|
||
}
|
||
|
||
static emacs_value
|
||
module_make_string (emacs_env *env, const char *str, ptrdiff_t len)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
if (! (0 <= len && len <= STRING_BYTES_BOUND))
|
||
overflow_error ();
|
||
Lisp_Object lstr
|
||
= len == 0 ? empty_multibyte_string : module_decode_utf_8 (str, len);
|
||
return lisp_to_value (env, lstr);
|
||
}
|
||
|
||
static emacs_value
|
||
module_make_unibyte_string (emacs_env *env, const char *str, ptrdiff_t length)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
if (! (0 <= length && length <= STRING_BYTES_BOUND))
|
||
overflow_error ();
|
||
Lisp_Object lstr
|
||
= length == 0 ? empty_unibyte_string : make_unibyte_string (str, length);
|
||
return lisp_to_value (env, lstr);
|
||
}
|
||
|
||
static emacs_value
|
||
module_make_user_ptr (emacs_env *env, emacs_finalizer fin, void *ptr)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
return lisp_to_value (env, make_user_ptr (fin, ptr));
|
||
}
|
||
|
||
static void *
|
||
module_get_user_ptr (emacs_env *env, emacs_value arg)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
Lisp_Object lisp = value_to_lisp (arg);
|
||
CHECK_USER_PTR (lisp);
|
||
return XUSER_PTR (lisp)->p;
|
||
}
|
||
|
||
static void
|
||
module_set_user_ptr (emacs_env *env, emacs_value arg, void *ptr)
|
||
{
|
||
MODULE_FUNCTION_BEGIN ();
|
||
Lisp_Object lisp = value_to_lisp (arg);
|
||
CHECK_USER_PTR (lisp);
|
||
XUSER_PTR (lisp)->p = ptr;
|
||
}
|
||
|
||
static emacs_finalizer
|
||
module_get_user_finalizer (emacs_env *env, emacs_value arg)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
Lisp_Object lisp = value_to_lisp (arg);
|
||
CHECK_USER_PTR (lisp);
|
||
return XUSER_PTR (lisp)->finalizer;
|
||
}
|
||
|
||
static void
|
||
module_set_user_finalizer (emacs_env *env, emacs_value arg,
|
||
emacs_finalizer fin)
|
||
{
|
||
MODULE_FUNCTION_BEGIN ();
|
||
Lisp_Object lisp = value_to_lisp (arg);
|
||
CHECK_USER_PTR (lisp);
|
||
XUSER_PTR (lisp)->finalizer = fin;
|
||
}
|
||
|
||
static void
|
||
check_vec_index (Lisp_Object lvec, ptrdiff_t i)
|
||
{
|
||
CHECK_VECTOR (lvec);
|
||
if (! (0 <= i && i < ASIZE (lvec)))
|
||
args_out_of_range_3 (INT_TO_INTEGER (i),
|
||
make_fixnum (0), make_fixnum (ASIZE (lvec) - 1));
|
||
}
|
||
|
||
static void
|
||
module_vec_set (emacs_env *env, emacs_value vector, ptrdiff_t index,
|
||
emacs_value value)
|
||
{
|
||
MODULE_FUNCTION_BEGIN ();
|
||
Lisp_Object lisp = value_to_lisp (vector);
|
||
check_vec_index (lisp, index);
|
||
ASET (lisp, index, value_to_lisp (value));
|
||
}
|
||
|
||
static emacs_value
|
||
module_vec_get (emacs_env *env, emacs_value vector, ptrdiff_t index)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
Lisp_Object lisp = value_to_lisp (vector);
|
||
check_vec_index (lisp, index);
|
||
return lisp_to_value (env, AREF (lisp, index));
|
||
}
|
||
|
||
static ptrdiff_t
|
||
module_vec_size (emacs_env *env, emacs_value vector)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (0);
|
||
Lisp_Object lisp = value_to_lisp (vector);
|
||
CHECK_VECTOR (lisp);
|
||
return ASIZE (lisp);
|
||
}
|
||
|
||
/* This function should return true if and only if maybe_quit would
|
||
quit. */
|
||
static bool
|
||
module_should_quit (emacs_env *env)
|
||
{
|
||
MODULE_FUNCTION_BEGIN_NO_CATCH (false);
|
||
return QUITP;
|
||
}
|
||
|
||
static enum emacs_process_input_result
|
||
module_process_input (emacs_env *env)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (emacs_process_input_quit);
|
||
maybe_quit ();
|
||
return emacs_process_input_continue;
|
||
}
|
||
|
||
static struct timespec
|
||
module_extract_time (emacs_env *env, emacs_value arg)
|
||
{
|
||
MODULE_FUNCTION_BEGIN ((struct timespec) {0});
|
||
return lisp_time_argument (value_to_lisp (arg));
|
||
}
|
||
|
||
static emacs_value
|
||
module_make_time (emacs_env *env, struct timespec time)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
return lisp_to_value (env, timespec_to_lisp (time));
|
||
}
|
||
|
||
/*
|
||
Big integer support.
|
||
|
||
There are two possible ways to support big integers in the module API
|
||
that have been discussed:
|
||
|
||
1. Exposing GMP numbers (mpz_t) directly in the API.
|
||
|
||
2. Isolating the API from GMP by converting to/from a custom
|
||
sign-magnitude representation.
|
||
|
||
Approach (1) has the advantage of being faster (no import/export
|
||
required) and requiring less code in Emacs and in modules that would
|
||
use GMP anyway. However, (1) also couples big integer support
|
||
directly to the current implementation in Emacs (GMP). Also (1)
|
||
requires each module author to ensure that their module is linked to
|
||
the same GMP library as Emacs itself; in particular, module authors
|
||
can't link GMP statically. (1) also requires conditional compilation
|
||
and workarounds to ensure the module interface still works if GMP
|
||
isn't available while including emacs-module.h. It also means that
|
||
modules written in languages such as Go and Java that support big
|
||
integers without GMP now have to carry an otherwise unnecessary GMP
|
||
dependency. Approach (2), on the other hand, neatly decouples the
|
||
module interface from the GMP-based implementation. It's not
|
||
significantly more complex than (1) either: the additional code is
|
||
mostly straightforward. Over all, the benefits of (2) over (1) are
|
||
large enough to prefer it here.
|
||
|
||
We use a simple sign-magnitude representation for the big integers.
|
||
For the magnitude we pick an array of an unsigned integer type similar
|
||
to mp_limb_t instead of e.g. unsigned char. This matches in most
|
||
cases the representation of a GMP limb. In such cases GMP picks an
|
||
optimized algorithm for mpz_import and mpz_export that boils down to a
|
||
single memcpy to convert the magnitude. This way we largely avoid the
|
||
import/export overhead on most platforms.
|
||
*/
|
||
|
||
/* Documented maximum count of magnitude elements. */
|
||
#define module_bignum_count_max \
|
||
((ptrdiff_t) min (SIZE_MAX, PTRDIFF_MAX) / sizeof (emacs_limb_t))
|
||
|
||
/* Verify that emacs_limb_t indeed has unique object
|
||
representations. */
|
||
verify (CHAR_BIT == 8);
|
||
verify ((sizeof (emacs_limb_t) == 4 && EMACS_LIMB_MAX == 0xFFFFFFFF)
|
||
|| (sizeof (emacs_limb_t) == 8
|
||
&& EMACS_LIMB_MAX == 0xFFFFFFFFFFFFFFFF));
|
||
|
||
static bool
|
||
module_extract_big_integer (emacs_env *env, emacs_value arg, int *sign,
|
||
ptrdiff_t *count, emacs_limb_t *magnitude)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (false);
|
||
Lisp_Object o = value_to_lisp (arg);
|
||
CHECK_INTEGER (o);
|
||
int dummy;
|
||
if (sign == NULL)
|
||
sign = &dummy;
|
||
/* See
|
||
https://gmplib.org/manual/Integer-Import-and-Export.html#index-Export. */
|
||
enum
|
||
{
|
||
order = -1,
|
||
size = sizeof *magnitude,
|
||
bits = size * CHAR_BIT,
|
||
endian = 0,
|
||
nails = 0,
|
||
numb = 8 * size - nails
|
||
};
|
||
if (FIXNUMP (o))
|
||
{
|
||
EMACS_INT x = XFIXNUM (o);
|
||
*sign = (0 < x) - (x < 0);
|
||
if (x == 0 || count == NULL)
|
||
return true;
|
||
/* As a simplification we don't check how many array elements
|
||
are exactly required, but use a reasonable static upper
|
||
bound. For most architectures exactly one element should
|
||
suffice. */
|
||
EMACS_UINT u;
|
||
enum { required = (sizeof u + size - 1) / size };
|
||
verify (0 < required && +required <= module_bignum_count_max);
|
||
if (magnitude == NULL)
|
||
{
|
||
*count = required;
|
||
return true;
|
||
}
|
||
if (*count < required)
|
||
{
|
||
ptrdiff_t actual = *count;
|
||
*count = required;
|
||
args_out_of_range_3 (INT_TO_INTEGER (actual),
|
||
INT_TO_INTEGER (required),
|
||
INT_TO_INTEGER (module_bignum_count_max));
|
||
}
|
||
/* Set u = abs(x). See https://stackoverflow.com/a/17313717. */
|
||
if (0 < x)
|
||
u = (EMACS_UINT) x;
|
||
else
|
||
u = -(EMACS_UINT) x;
|
||
verify (required * bits < PTRDIFF_MAX);
|
||
for (ptrdiff_t i = 0; i < required; ++i)
|
||
magnitude[i] = (emacs_limb_t) (u >> (i * bits));
|
||
return true;
|
||
}
|
||
const mpz_t *x = xbignum_val (o);
|
||
*sign = mpz_sgn (*x);
|
||
if (count == NULL)
|
||
return true;
|
||
size_t required_size = (mpz_sizeinbase (*x, 2) + numb - 1) / numb;
|
||
eassert (required_size <= PTRDIFF_MAX);
|
||
ptrdiff_t required = (ptrdiff_t) required_size;
|
||
eassert (required <= module_bignum_count_max);
|
||
if (magnitude == NULL)
|
||
{
|
||
*count = required;
|
||
return true;
|
||
}
|
||
if (*count < required)
|
||
{
|
||
ptrdiff_t actual = *count;
|
||
*count = required;
|
||
args_out_of_range_3 (INT_TO_INTEGER (actual), INT_TO_INTEGER (required),
|
||
INT_TO_INTEGER (module_bignum_count_max));
|
||
}
|
||
size_t written;
|
||
mpz_export (magnitude, &written, order, size, endian, nails, *x);
|
||
eassert (written == required_size);
|
||
return true;
|
||
}
|
||
|
||
static emacs_value
|
||
module_make_big_integer (emacs_env *env, int sign,
|
||
ptrdiff_t count, const emacs_limb_t *magnitude)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (NULL);
|
||
if (sign == 0)
|
||
return lisp_to_value (env, make_fixed_natnum (0));
|
||
enum { order = -1, size = sizeof *magnitude, endian = 0, nails = 0 };
|
||
mpz_import (mpz[0], count, order, size, endian, nails, magnitude);
|
||
if (sign < 0)
|
||
mpz_neg (mpz[0], mpz[0]);
|
||
return lisp_to_value (env, make_integer_mpz ());
|
||
}
|
||
|
||
static int
|
||
module_open_channel (emacs_env *env, emacs_value pipe_process)
|
||
{
|
||
MODULE_FUNCTION_BEGIN (-1);
|
||
return open_channel_for_module (value_to_lisp (pipe_process));
|
||
}
|
||
|
||
|
||
/* Subroutines. */
|
||
|
||
static void
|
||
module_signal_or_throw (struct emacs_env_private *env)
|
||
{
|
||
switch (env->pending_non_local_exit)
|
||
{
|
||
case emacs_funcall_exit_return:
|
||
return;
|
||
case emacs_funcall_exit_signal:
|
||
xsignal (value_to_lisp (&env->non_local_exit_symbol),
|
||
value_to_lisp (&env->non_local_exit_data));
|
||
case emacs_funcall_exit_throw:
|
||
Fthrow (value_to_lisp (&env->non_local_exit_symbol),
|
||
value_to_lisp (&env->non_local_exit_data));
|
||
default:
|
||
eassume (false);
|
||
}
|
||
}
|
||
|
||
DEFUN ("module-load", Fmodule_load, Smodule_load, 1, 1, 0,
|
||
doc: /* Load module FILE. */)
|
||
(Lisp_Object file)
|
||
{
|
||
dynlib_handle_ptr handle;
|
||
emacs_init_function module_init;
|
||
void *gpl_sym;
|
||
|
||
CHECK_STRING (file);
|
||
handle = dynlib_open (SSDATA (file));
|
||
if (!handle)
|
||
xsignal2 (Qmodule_open_failed, file, build_string (dynlib_error ()));
|
||
|
||
gpl_sym = dynlib_sym (handle, "plugin_is_GPL_compatible");
|
||
if (!gpl_sym)
|
||
xsignal1 (Qmodule_not_gpl_compatible, file);
|
||
|
||
module_init = (emacs_init_function) dynlib_func (handle, "emacs_module_init");
|
||
if (!module_init)
|
||
xsignal1 (Qmissing_module_init_function, file);
|
||
|
||
struct emacs_runtime rt_pub;
|
||
struct emacs_runtime_private rt_priv;
|
||
emacs_env env_pub;
|
||
struct emacs_env_private env_priv;
|
||
rt_priv.env = initialize_environment (&env_pub, &env_priv);
|
||
|
||
/* If we should use module assertions, reallocate the runtime object
|
||
from the free store, but never free it. That way the addresses
|
||
for two different runtime objects are guaranteed to be distinct,
|
||
which we can use for checking the liveness of runtime
|
||
pointers. */
|
||
struct emacs_runtime *rt;
|
||
if (module_assertions)
|
||
{
|
||
rt = xmalloc (sizeof *rt);
|
||
__lsan_ignore_object (rt);
|
||
}
|
||
else
|
||
rt = &rt_pub;
|
||
rt->size = sizeof *rt;
|
||
rt->private_members = &rt_priv;
|
||
rt->get_environment = module_get_environment;
|
||
|
||
specpdl_ref count = SPECPDL_INDEX ();
|
||
record_unwind_protect_module (SPECPDL_MODULE_RUNTIME, rt);
|
||
record_unwind_protect_module (SPECPDL_MODULE_ENVIRONMENT, rt_priv.env);
|
||
|
||
int r = module_init (rt);
|
||
|
||
/* Process the quit flag first, so that quitting doesn't get
|
||
overridden by other non-local exits. */
|
||
maybe_quit ();
|
||
|
||
if (r != 0)
|
||
xsignal2 (Qmodule_init_failed, file, INT_TO_INTEGER (r));
|
||
|
||
module_signal_or_throw (&env_priv);
|
||
return unbind_to (count, Qt);
|
||
}
|
||
|
||
Lisp_Object
|
||
funcall_module (Lisp_Object function, ptrdiff_t nargs, Lisp_Object *arglist)
|
||
{
|
||
const struct Lisp_Module_Function *func = XMODULE_FUNCTION (function);
|
||
eassume (0 <= func->min_arity);
|
||
if (! (func->min_arity <= nargs
|
||
&& (func->max_arity < 0 || nargs <= func->max_arity)))
|
||
xsignal2 (Qwrong_number_of_arguments, function, make_fixnum (nargs));
|
||
|
||
emacs_env pub;
|
||
struct emacs_env_private priv;
|
||
emacs_env *env = initialize_environment (&pub, &priv);
|
||
specpdl_ref count = SPECPDL_INDEX ();
|
||
record_unwind_protect_module (SPECPDL_MODULE_ENVIRONMENT, env);
|
||
|
||
USE_SAFE_ALLOCA;
|
||
emacs_value *args = nargs > 0 ? SAFE_ALLOCA (nargs * sizeof *args) : NULL;
|
||
for (ptrdiff_t i = 0; i < nargs; ++i)
|
||
{
|
||
args[i] = lisp_to_value (env, arglist[i]);
|
||
if (! args[i])
|
||
memory_full (sizeof *args[i]);
|
||
}
|
||
|
||
/* The only possibility of getting an error until here is failure to
|
||
allocate memory for the arguments, but then we already should
|
||
have signaled an error before. */
|
||
eassert (priv.pending_non_local_exit == emacs_funcall_exit_return);
|
||
|
||
emacs_value ret = func->subr (env, nargs, args, func->data);
|
||
|
||
eassert (&priv == env->private_members);
|
||
|
||
/* Process the quit flag first, so that quitting doesn't get
|
||
overridden by other non-local exits. */
|
||
maybe_quit ();
|
||
|
||
module_signal_or_throw (&priv);
|
||
return SAFE_FREE_UNBIND_TO (count, value_to_lisp (ret));
|
||
}
|
||
|
||
Lisp_Object
|
||
module_function_arity (const struct Lisp_Module_Function *const function)
|
||
{
|
||
ptrdiff_t minargs = function->min_arity;
|
||
ptrdiff_t maxargs = function->max_arity;
|
||
return Fcons (make_fixnum (minargs),
|
||
maxargs == MANY ? Qmany : make_fixnum (maxargs));
|
||
}
|
||
|
||
Lisp_Object
|
||
module_function_documentation (const struct Lisp_Module_Function *function)
|
||
{
|
||
return function->documentation;
|
||
}
|
||
|
||
module_funcptr
|
||
module_function_address (const struct Lisp_Module_Function *function)
|
||
{
|
||
return (module_funcptr) function->subr;
|
||
}
|
||
|
||
void *
|
||
module_function_data (const struct Lisp_Module_Function *function)
|
||
{
|
||
return function->data;
|
||
}
|
||
|
||
|
||
/* Helper functions. */
|
||
|
||
static void
|
||
module_assert_thread (void)
|
||
{
|
||
if (!module_assertions)
|
||
return;
|
||
if (!in_current_thread ())
|
||
module_abort ("Module function called from outside "
|
||
"the current Lisp thread");
|
||
if (gc_in_progress)
|
||
module_abort ("Module function called during garbage collection");
|
||
}
|
||
|
||
static void
|
||
module_assert_runtime (struct emacs_runtime *runtime)
|
||
{
|
||
if (! module_assertions)
|
||
return;
|
||
ptrdiff_t count = 0;
|
||
for (const union specbinding *pdl = specpdl; pdl != specpdl_ptr; ++pdl)
|
||
if (pdl->kind == SPECPDL_MODULE_RUNTIME)
|
||
{
|
||
if (pdl->unwind_ptr.arg == runtime)
|
||
return;
|
||
++count;
|
||
}
|
||
module_abort ("Runtime pointer not found in list of %"pD"d runtimes",
|
||
count);
|
||
}
|
||
|
||
static void
|
||
module_assert_env (emacs_env *env)
|
||
{
|
||
if (! module_assertions)
|
||
return;
|
||
ptrdiff_t count = 0;
|
||
for (const union specbinding *pdl = specpdl; pdl != specpdl_ptr; ++pdl)
|
||
if (pdl->kind == SPECPDL_MODULE_ENVIRONMENT)
|
||
{
|
||
if (pdl->unwind_ptr.arg == env)
|
||
return;
|
||
++count;
|
||
}
|
||
module_abort ("Environment pointer not found in list of %"pD"d environments",
|
||
count);
|
||
}
|
||
|
||
static void
|
||
module_non_local_exit_signal_1 (emacs_env *env, Lisp_Object sym,
|
||
Lisp_Object data)
|
||
{
|
||
struct emacs_env_private *p = env->private_members;
|
||
if (p->pending_non_local_exit == emacs_funcall_exit_return)
|
||
{
|
||
p->pending_non_local_exit = emacs_funcall_exit_signal;
|
||
p->non_local_exit_symbol.v = sym;
|
||
p->non_local_exit_data.v = data;
|
||
}
|
||
}
|
||
|
||
static void
|
||
module_non_local_exit_throw_1 (emacs_env *env, Lisp_Object tag,
|
||
Lisp_Object value)
|
||
{
|
||
struct emacs_env_private *p = env->private_members;
|
||
if (p->pending_non_local_exit == emacs_funcall_exit_return)
|
||
{
|
||
p->pending_non_local_exit = emacs_funcall_exit_throw;
|
||
p->non_local_exit_symbol.v = tag;
|
||
p->non_local_exit_data.v = value;
|
||
}
|
||
}
|
||
|
||
/* Signal an out-of-memory condition to the caller. */
|
||
static void
|
||
module_out_of_memory (emacs_env *env)
|
||
{
|
||
/* TODO: Reimplement this so it works even if memory-signal-data has
|
||
been modified. */
|
||
module_non_local_exit_signal_1 (env, XCAR (Vmemory_signal_data),
|
||
XCDR (Vmemory_signal_data));
|
||
}
|
||
|
||
|
||
/* Value conversion. */
|
||
|
||
/* Convert an `emacs_value' to the corresponding internal object.
|
||
Never fails. */
|
||
|
||
/* If V was computed from lisp_to_value (O), then return O.
|
||
Exits non-locally only if the stack overflows. */
|
||
static Lisp_Object
|
||
value_to_lisp (emacs_value v)
|
||
{
|
||
if (module_assertions)
|
||
{
|
||
/* Check the liveness of the value by iterating over all live
|
||
environments. */
|
||
ptrdiff_t num_environments = 0;
|
||
ptrdiff_t num_values = 0;
|
||
for (const union specbinding *pdl = specpdl; pdl != specpdl_ptr; ++pdl)
|
||
if (pdl->kind == SPECPDL_MODULE_ENVIRONMENT)
|
||
{
|
||
const emacs_env *env = pdl->unwind_ptr.arg;
|
||
struct emacs_env_private *priv = env->private_members;
|
||
/* The value might be one of the nonlocal exit values. Note
|
||
that we don't check whether a nonlocal exit is currently
|
||
pending, because the module might have cleared the flag
|
||
in the meantime. */
|
||
if (&priv->non_local_exit_symbol == v
|
||
|| &priv->non_local_exit_data == v)
|
||
goto ok;
|
||
if (value_storage_contains_p (&priv->storage, v, &num_values))
|
||
goto ok;
|
||
++num_environments;
|
||
}
|
||
/* Also check global values. */
|
||
if (module_global_reference_p (v, &num_values))
|
||
goto ok;
|
||
module_abort (("Emacs value not found in %"pD"d values "
|
||
"of %"pD"d environments"),
|
||
num_values, num_environments);
|
||
}
|
||
|
||
ok: return v->v;
|
||
}
|
||
|
||
/* Convert an internal object to an `emacs_value'. Allocate storage
|
||
from the environment; return NULL if allocation fails. */
|
||
static emacs_value
|
||
lisp_to_value (emacs_env *env, Lisp_Object o)
|
||
{
|
||
struct emacs_env_private *p = env->private_members;
|
||
if (p->pending_non_local_exit != emacs_funcall_exit_return)
|
||
return NULL;
|
||
return allocate_emacs_value (env, o);
|
||
}
|
||
|
||
/* Must be called for each frame before it can be used for allocation. */
|
||
static void
|
||
initialize_frame (struct emacs_value_frame *frame)
|
||
{
|
||
frame->offset = 0;
|
||
frame->next = NULL;
|
||
}
|
||
|
||
/* Must be called for any storage object before it can be used for
|
||
allocation. */
|
||
static void
|
||
initialize_storage (struct emacs_value_storage *storage)
|
||
{
|
||
initialize_frame (&storage->initial);
|
||
storage->current = &storage->initial;
|
||
}
|
||
|
||
/* Must be called for any initialized storage object before its
|
||
lifetime ends. Free all dynamically-allocated frames. */
|
||
static void
|
||
finalize_storage (struct emacs_value_storage *storage)
|
||
{
|
||
struct emacs_value_frame *next = storage->initial.next;
|
||
while (next != NULL)
|
||
{
|
||
struct emacs_value_frame *current = next;
|
||
next = current->next;
|
||
free (current);
|
||
}
|
||
}
|
||
|
||
/* Allocate a new value from STORAGE and stores OBJ in it. Return
|
||
NULL if allocation fails and use ENV for non local exit reporting. */
|
||
static emacs_value
|
||
allocate_emacs_value (emacs_env *env, Lisp_Object obj)
|
||
{
|
||
struct emacs_value_storage *storage = &env->private_members->storage;
|
||
eassert (storage->current);
|
||
eassert (storage->current->offset < value_frame_size);
|
||
eassert (! storage->current->next);
|
||
if (storage->current->offset == value_frame_size - 1)
|
||
{
|
||
storage->current->next = malloc (sizeof *storage->current->next);
|
||
if (! storage->current->next)
|
||
{
|
||
module_out_of_memory (env);
|
||
return NULL;
|
||
}
|
||
initialize_frame (storage->current->next);
|
||
storage->current = storage->current->next;
|
||
}
|
||
emacs_value value = storage->current->objects + storage->current->offset;
|
||
value->v = obj;
|
||
++storage->current->offset;
|
||
return value;
|
||
}
|
||
|
||
/* Mark all objects allocated from local environments so that they
|
||
don't get garbage-collected. */
|
||
void
|
||
mark_module_environment (void *ptr)
|
||
{
|
||
emacs_env *env = ptr;
|
||
struct emacs_env_private *priv = env->private_members;
|
||
for (struct emacs_value_frame *frame = &priv->storage.initial; frame != NULL;
|
||
frame = frame->next)
|
||
for (int i = 0; i < frame->offset; ++i)
|
||
mark_object (frame->objects[i].v);
|
||
}
|
||
|
||
|
||
/* Environment lifetime management. */
|
||
|
||
/* Must be called before the environment can be used. Returns another
|
||
pointer that callers should use instead of the ENV argument. If
|
||
module assertions are disabled, the return value is ENV. If module
|
||
assertions are enabled, the return value points to a heap-allocated
|
||
object. That object is never freed to guarantee unique
|
||
addresses. */
|
||
static emacs_env *
|
||
initialize_environment (emacs_env *env, struct emacs_env_private *priv)
|
||
{
|
||
if (module_assertions)
|
||
{
|
||
env = xmalloc (sizeof *env);
|
||
__lsan_ignore_object (env);
|
||
}
|
||
|
||
priv->pending_non_local_exit = emacs_funcall_exit_return;
|
||
initialize_storage (&priv->storage);
|
||
env->size = sizeof *env;
|
||
env->private_members = priv;
|
||
env->make_global_ref = module_make_global_ref;
|
||
env->free_global_ref = module_free_global_ref;
|
||
env->non_local_exit_check = module_non_local_exit_check;
|
||
env->non_local_exit_clear = module_non_local_exit_clear;
|
||
env->non_local_exit_get = module_non_local_exit_get;
|
||
env->non_local_exit_signal = module_non_local_exit_signal;
|
||
env->non_local_exit_throw = module_non_local_exit_throw;
|
||
env->make_function = module_make_function;
|
||
env->funcall = module_funcall;
|
||
env->intern = module_intern;
|
||
env->type_of = module_type_of;
|
||
env->is_not_nil = module_is_not_nil;
|
||
env->eq = module_eq;
|
||
env->extract_integer = module_extract_integer;
|
||
env->make_integer = module_make_integer;
|
||
env->extract_float = module_extract_float;
|
||
env->make_float = module_make_float;
|
||
env->copy_string_contents = module_copy_string_contents;
|
||
env->make_string = module_make_string;
|
||
env->make_unibyte_string = module_make_unibyte_string;
|
||
env->make_user_ptr = module_make_user_ptr;
|
||
env->get_user_ptr = module_get_user_ptr;
|
||
env->set_user_ptr = module_set_user_ptr;
|
||
env->get_user_finalizer = module_get_user_finalizer;
|
||
env->set_user_finalizer = module_set_user_finalizer;
|
||
env->vec_set = module_vec_set;
|
||
env->vec_get = module_vec_get;
|
||
env->vec_size = module_vec_size;
|
||
env->should_quit = module_should_quit;
|
||
env->process_input = module_process_input;
|
||
env->extract_time = module_extract_time;
|
||
env->make_time = module_make_time;
|
||
env->extract_big_integer = module_extract_big_integer;
|
||
env->make_big_integer = module_make_big_integer;
|
||
env->get_function_finalizer = module_get_function_finalizer;
|
||
env->set_function_finalizer = module_set_function_finalizer;
|
||
env->open_channel = module_open_channel;
|
||
env->make_interactive = module_make_interactive;
|
||
return env;
|
||
}
|
||
|
||
/* Must be called before the lifetime of the environment object
|
||
ends. */
|
||
static void
|
||
finalize_environment (emacs_env *env)
|
||
{
|
||
finalize_storage (&env->private_members->storage);
|
||
}
|
||
|
||
void
|
||
finalize_environment_unwind (void *env)
|
||
{
|
||
finalize_environment (env);
|
||
}
|
||
|
||
void
|
||
finalize_runtime_unwind (void *raw_ert)
|
||
{
|
||
/* No further cleanup is required, as the initial environment is
|
||
unwound separately. See the logic in Fmodule_load. */
|
||
}
|
||
|
||
|
||
/* Non-local exit handling. */
|
||
|
||
/* Must be called after setting up a handler immediately before
|
||
returning from the function. See the comments in lisp.h and the
|
||
code in eval.c for details. The macros below arrange for this
|
||
function to be called automatically. PHANDLERLIST points to a word
|
||
containing the handler list, for sanity checking. */
|
||
static void
|
||
module_reset_handlerlist (struct handler **phandlerlist)
|
||
{
|
||
eassert (handlerlist == *phandlerlist);
|
||
handlerlist = handlerlist->next;
|
||
}
|
||
|
||
/* Called on `signal' and `throw'. DATA is a pair
|
||
(ERROR-SYMBOL . ERROR-DATA) or (TAG . VALUE), which gets stored in
|
||
the environment. Set the pending non-local exit flag. */
|
||
static void
|
||
module_handle_nonlocal_exit (emacs_env *env, enum nonlocal_exit type,
|
||
Lisp_Object data)
|
||
{
|
||
switch (type)
|
||
{
|
||
case NONLOCAL_EXIT_SIGNAL:
|
||
module_non_local_exit_signal_1 (env, XCAR (data), XCDR (data));
|
||
break;
|
||
case NONLOCAL_EXIT_THROW:
|
||
module_non_local_exit_throw_1 (env, XCAR (data), XCDR (data));
|
||
break;
|
||
}
|
||
}
|
||
|
||
|
||
/* Support for assertions. */
|
||
void
|
||
init_module_assertions (bool enable)
|
||
{
|
||
module_assertions = enable;
|
||
}
|
||
|
||
/* Return whether STORAGE contains VALUE. Used to check module
|
||
assertions. Increment *COUNT by the number of values searched. */
|
||
|
||
static bool
|
||
value_storage_contains_p (const struct emacs_value_storage *storage,
|
||
emacs_value value, ptrdiff_t *count)
|
||
{
|
||
for (const struct emacs_value_frame *frame = &storage->initial; frame != NULL;
|
||
frame = frame->next)
|
||
{
|
||
for (int i = 0; i < frame->offset; ++i)
|
||
{
|
||
if (&frame->objects[i] == value)
|
||
return true;
|
||
++*count;
|
||
}
|
||
}
|
||
return false;
|
||
}
|
||
|
||
static AVOID ATTRIBUTE_FORMAT_PRINTF (1, 2)
|
||
module_abort (const char *format, ...)
|
||
{
|
||
fputs ("Emacs module assertion: ", stderr);
|
||
va_list args;
|
||
va_start (args, format);
|
||
vfprintf (stderr, format, args);
|
||
va_end (args);
|
||
putc ('\n', stderr);
|
||
fflush (NULL);
|
||
emacs_abort ();
|
||
}
|
||
|
||
|
||
/* Segment initializer. */
|
||
|
||
void
|
||
syms_of_module (void)
|
||
{
|
||
staticpro (&Vmodule_refs_hash);
|
||
Vmodule_refs_hash
|
||
= make_hash_table (hashtest_eq, DEFAULT_HASH_SIZE,
|
||
DEFAULT_REHASH_SIZE, DEFAULT_REHASH_THRESHOLD,
|
||
Qnil, false);
|
||
|
||
DEFSYM (Qmodule_load_failed, "module-load-failed");
|
||
Fput (Qmodule_load_failed, Qerror_conditions,
|
||
pure_list (Qmodule_load_failed, Qerror));
|
||
Fput (Qmodule_load_failed, Qerror_message,
|
||
build_pure_c_string ("Module load failed"));
|
||
|
||
DEFSYM (Qmodule_open_failed, "module-open-failed");
|
||
Fput (Qmodule_open_failed, Qerror_conditions,
|
||
pure_list (Qmodule_open_failed, Qmodule_load_failed, Qerror));
|
||
Fput (Qmodule_open_failed, Qerror_message,
|
||
build_pure_c_string ("Module could not be opened"));
|
||
|
||
DEFSYM (Qmodule_not_gpl_compatible, "module-not-gpl-compatible");
|
||
Fput (Qmodule_not_gpl_compatible, Qerror_conditions,
|
||
pure_list (Qmodule_not_gpl_compatible, Qmodule_load_failed, Qerror));
|
||
Fput (Qmodule_not_gpl_compatible, Qerror_message,
|
||
build_pure_c_string ("Module is not GPL compatible"));
|
||
|
||
DEFSYM (Qmissing_module_init_function, "missing-module-init-function");
|
||
Fput (Qmissing_module_init_function, Qerror_conditions,
|
||
pure_list (Qmissing_module_init_function, Qmodule_load_failed,
|
||
Qerror));
|
||
Fput (Qmissing_module_init_function, Qerror_message,
|
||
build_pure_c_string ("Module does not export an "
|
||
"initialization function"));
|
||
|
||
DEFSYM (Qmodule_init_failed, "module-init-failed");
|
||
Fput (Qmodule_init_failed, Qerror_conditions,
|
||
pure_list (Qmodule_init_failed, Qmodule_load_failed, Qerror));
|
||
Fput (Qmodule_init_failed, Qerror_message,
|
||
build_pure_c_string ("Module initialization failed"));
|
||
|
||
DEFSYM (Qinvalid_arity, "invalid-arity");
|
||
Fput (Qinvalid_arity, Qerror_conditions, pure_list (Qinvalid_arity, Qerror));
|
||
Fput (Qinvalid_arity, Qerror_message,
|
||
build_pure_c_string ("Invalid function arity"));
|
||
|
||
DEFSYM (Qmodule_function_p, "module-function-p");
|
||
DEFSYM (Qunicode_string_p, "unicode-string-p");
|
||
|
||
defsubr (&Smodule_load);
|
||
}
|