/* Copyright 1995-1998,2000-2003,2006,2008-2012,2018-2019
Free Software Foundation, Inc.
This file is part of Guile.
Guile is free software: you can redistribute it and/or modify it
under the terms of the GNU Lesser General Public License as published
by the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Guile 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 Lesser General Public
License for more details.
You should have received a copy of the GNU Lesser General Public
License along with Guile. If not, see
. */
#ifdef HAVE_CONFIG_H
# include
#endif
#include "boolean.h"
#include "gsubr.h"
#include "modules.h"
#include "ports.h"
#include "print.h"
#include "private-options.h"
#include "procs.h"
#include "random.h"
#include "smob.h"
#include "symbols.h"
#include "variable.h"
#include "macros.h"
static scm_t_bits scm_tc16_macro;
#define SCM_MACROP(x) SCM_SMOB_PREDICATE (scm_tc16_macro, (x))
#define SCM_MACRO_PRIMITIVE(m) ((scm_t_macro_primitive)SCM_SMOB_DATA (m))
#define SCM_MACRO_NAME(m) (SCM_SMOB_OBJECT_2 (m))
#define SCM_MACRO_TYPE(m) (SCM_SMOB_OBJECT_3 (m))
#define SCM_MACRO_BINDING(m) (SCM_CELL_OBJECT ((m), 4))
#define SCM_VALIDATE_MACRO(p,v) SCM_MAKE_VALIDATE ((p), (v), MACROP)
SCM_API scm_t_bits scm_tc16_macro;
static int
macro_print (SCM macro, SCM port, scm_print_state *pstate)
{
if (scm_is_false (SCM_MACRO_TYPE (macro)))
scm_puts ("#', port);
return 1;
}
SCM_SYMBOL (sym_primitive_macro, "primitive-macro");
/* Return a mmacro that is known to be one of guile's built in macros. */
SCM
scm_i_make_primitive_macro (const char *name, scm_t_macro_primitive fn)
{
SCM z = scm_words (scm_tc16_macro, 5);
SCM_SET_SMOB_DATA_N (z, 1, (scm_t_bits)fn);
SCM_SET_SMOB_OBJECT_N (z, 2, scm_from_utf8_symbol (name));
SCM_SET_SMOB_OBJECT_N (z, 3, sym_primitive_macro);
SCM_SET_SMOB_OBJECT_N (z, 4, SCM_BOOL_F);
return z;
}
scm_t_macro_primitive
scm_i_macro_primitive (SCM macro)
{
return SCM_MACRO_PRIMITIVE (macro);
}
SCM_DEFINE (scm_make_syntax_transformer, "make-syntax-transformer", 3, 0, 0,
(SCM name, SCM type, SCM binding),
"Construct a @dfn{syntax transformer}.\n\n"
"This function is part of Guile's low-level support for the psyntax\n"
"syntax expander. Users should not call this function.")
#define FUNC_NAME s_scm_make_syntax_transformer
{
SCM z;
SCM (*prim)(SCM,SCM) = NULL;
if (scm_is_true (name))
{
SCM existing_var;
SCM_VALIDATE_SYMBOL (1, name);
existing_var = scm_module_variable (scm_current_module (), name);
if (scm_is_true (existing_var)
&& scm_is_true (scm_variable_bound_p (existing_var))
&& SCM_MACROP (SCM_VARIABLE_REF (existing_var)))
prim = SCM_MACRO_PRIMITIVE (SCM_VARIABLE_REF (existing_var));
}
SCM_VALIDATE_SYMBOL (2, type);
z = scm_words (scm_tc16_macro, 5);
SCM_SET_SMOB_DATA_N (z, 1, prim);
SCM_SET_SMOB_OBJECT_N (z, 2, name);
SCM_SET_SMOB_OBJECT_N (z, 3, type);
SCM_SET_SMOB_OBJECT_N (z, 4, binding);
return z;
}
#undef FUNC_NAME
SCM_DEFINE (scm_macro_p, "macro?", 1, 0, 0,
(SCM obj),
"Return @code{#t} if @var{obj} is a syntax transformer (an object that "
"transforms Scheme expressions at expansion-time).\n\n"
"Macros are actually just one kind of syntax transformer; this\n"
"procedure has its name due to historical reasons.")
#define FUNC_NAME s_scm_macro_p
{
return scm_from_bool (SCM_MACROP (obj));
}
#undef FUNC_NAME
SCM_DEFINE (scm_macro_type, "macro-type", 1, 0, 0,
(SCM m),
"Return the type of the syntax transformer @var{m}, as passed to\n"
"@code{make-syntax-transformer}. If @var{m} is a primitive syntax\n"
"transformer, @code{#f} will be returned.")
#define FUNC_NAME s_scm_macro_type
{
SCM_VALIDATE_MACRO (1, m);
return SCM_MACRO_TYPE (m);
}
#undef FUNC_NAME
SCM_DEFINE (scm_macro_name, "macro-name", 1, 0, 0,
(SCM m),
"Return the name of the syntax transformer @var{m}.")
#define FUNC_NAME s_scm_macro_name
{
SCM_VALIDATE_MACRO (1, m);
return SCM_MACRO_NAME (m);
}
#undef FUNC_NAME
SCM_DEFINE (scm_macro_transformer, "macro-transformer", 1, 0, 0,
(SCM m),
"Return the transformer procedure of the macro @var{m}.\n\n"
"If @var{m} is a syntax transformer but not a macro, @code{#f}\n"
"will be returned. (This can happen, for example, with primitive\n"
"syntax transformers).")
#define FUNC_NAME s_scm_macro_transformer
{
SCM_VALIDATE_MACRO (1, m);
/* here we rely on knowledge of how psyntax represents macro bindings, but
hey, there is code out there that calls this function, and expects to get
a procedure in return... */
if (scm_is_true (scm_procedure_p (SCM_MACRO_BINDING (m))))
return SCM_MACRO_BINDING (m);
else
return SCM_BOOL_F;
}
#undef FUNC_NAME
SCM_DEFINE (scm_macro_binding, "macro-binding", 1, 0, 0,
(SCM m),
"Return the binding of the syntax transformer @var{m}, as passed to\n"
"@code{make-syntax-transformer}. If @var{m} is a primitive syntax\n"
"transformer, @code{#f} will be returned.")
#define FUNC_NAME s_scm_macro_binding
{
SCM_VALIDATE_MACRO (1, m);
return SCM_MACRO_BINDING (m);
}
#undef FUNC_NAME
static SCM syntax_session_id;
#define SESSION_ID_LENGTH 22 /* bytes */
#define BASE64_RADIX_BITS 6
#define BASE64_RADIX (1 << (BASE64_RADIX_BITS))
#define BASE64_MASK (BASE64_RADIX - 1)
static SCM
fresh_syntax_session_id (void)
{
static const char base64[BASE64_RADIX] =
"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789$@";
unsigned char digit_buf[SESSION_ID_LENGTH];
char char_buf[SESSION_ID_LENGTH];
size_t i;
scm_i_random_bytes_from_platform (digit_buf, SESSION_ID_LENGTH);
for (i = 0; i < SESSION_ID_LENGTH; ++i)
char_buf[i] = base64[digit_buf[i] & BASE64_MASK];
return scm_from_latin1_stringn (char_buf, SESSION_ID_LENGTH);
}
static SCM
scm_syntax_session_id (void)
{
return syntax_session_id;
}
void
scm_init_macros ()
{
scm_tc16_macro = scm_make_smob_type ("macro", 0);
scm_set_smob_print (scm_tc16_macro, macro_print);
#include "macros.x"
syntax_session_id = fresh_syntax_session_id();
scm_c_define_gsubr ("syntax-session-id", 0, 0, 0, scm_syntax_session_id);
}