/* Copyright (C) 1996, 1997 Free Software Foundation, Inc. * * This program 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 2, or (at your option) * any later version. * * This program 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 this software; see the file COPYING. If not, write to * the Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307 USA * * As a special exception, the Free Software Foundation gives permission * for additional uses of the text contained in its release of GUILE. * * The exception is that, if you link the GUILE library with other files * to produce an executable, this does not by itself cause the * resulting executable to be covered by the GNU General Public License. * Your use of that executable is in no way restricted on account of * linking the GUILE library code into it. * * This exception does not however invalidate any other reasons why * the executable file might be covered by the GNU General Public License. * * This exception applies only to the code released by the * Free Software Foundation under the name GUILE. If you copy * code from other Free Software Foundation releases into a copy of * GUILE, as the General Public License permits, the exception does * not apply to the code that you add in this way. To avoid misleading * anyone as to the status of such modified files, you must delete * this exception notice from them. * * If you write modifications of your own for GUILE, it is your choice * whether to permit this exception to apply to your modifications. * If you do not wish that, delete this exception notice. */ #include "_scm.h" #include "print.h" #include "smob.h" #include "dynwind.h" #include "fluids.h" #include "alist.h" #include "eval.h" #define INITIAL_FLUIDS 10 static volatile int n_fluids; long scm_tc16_fluid; SCM scm_make_initial_fluids () { return scm_make_vector (SCM_MAKINUM (INITIAL_FLUIDS), SCM_BOOL_F); } static void grow_fluids SCM_P ((scm_root_state *, int new_length)); static void grow_fluids (root_state, new_length) scm_root_state *root_state; int new_length; { SCM old_fluids, new_fluids; int old_length, i; old_fluids = root_state->fluids; old_length = SCM_LENGTH (old_fluids); new_fluids = scm_make_vector (SCM_MAKINUM (new_length), SCM_BOOL_F); i = 0; while (i < old_length) { SCM_VELTS(new_fluids)[i] = SCM_VELTS(old_fluids)[i]; i++; } while (i < new_length) { SCM_VELTS(new_fluids)[i] = SCM_BOOL_F; i++; } root_state->fluids = new_fluids; } void scm_copy_fluids (root_state) scm_root_state *root_state; { grow_fluids (root_state, SCM_LENGTH(root_state->fluids)); } static int print_fluid SCM_P ((SCM exp, SCM port, scm_print_state *pstate)); static int print_fluid (exp, port, pstate) SCM exp; SCM port; scm_print_state *pstate; { scm_puts ("#', port); return 1; } static scm_smobfuns fluid_smob = { 0, scm_free0, print_fluid }; static int next_fluid_num () { int n; #ifdef USE_THREADS SCM_THREAD_CRITICAL_SECTION_START; #endif n = n_fluids++; #ifdef USE_THREADS SCM_THREAD_CRITICAL_SECTION_END; #endif return n; } SCM_PROC (s_make_fluid, "make-fluid", 0, 0, 0, scm_make_fluid); SCM scm_make_fluid () { SCM z; int n; SCM_DEFER_INTS; n = next_fluid_num (); SCM_NEWCELL (z); SCM_SETCAR (z, scm_tc16_fluid); SCM_SETCDR (z, n); SCM_ALLOW_INTS; return z; } SCM_PROC (s_fluid_p, "fluid?", 1, 0, 0, scm_fluid_p); SCM scm_fluid_p (fl) SCM fl; { return (SCM_NIMP (fl) && SCM_FLUIDP (fl))? SCM_BOOL_T : SCM_BOOL_F; } SCM_PROC (s_fluid_ref, "fluid-ref", 1, 0, 0, scm_fluid_ref); SCM scm_fluid_ref (fl) SCM fl; { int n; SCM_ASSERT (SCM_NIMP (fl) && SCM_FLUIDP (fl), fl, SCM_ARG1, s_fluid_ref); n = SCM_FLUID_NUM (fl); if (SCM_LENGTH (scm_root->fluids) <= n) grow_fluids (scm_root, n+1); return SCM_VELTS(scm_root->fluids)[n]; } SCM_PROC (s_fluid_set_x, "fluid-set!", 2, 0, 0, scm_fluid_set_x); SCM scm_fluid_set_x (fl, val) SCM fl; SCM val; { int n; SCM_ASSERT (SCM_NIMP (fl) && SCM_FLUIDP (fl), fl, SCM_ARG1, s_fluid_set_x); n = SCM_FLUID_NUM (fl); if (SCM_LENGTH (scm_root->fluids) <= n) grow_fluids (scm_root, n+1); SCM_VELTS(scm_root->fluids)[n] = val; return val; } void scm_swap_fluids (fluids, vals) SCM fluids, vals; { while (SCM_NIMP (fluids)) { SCM fl = SCM_CAR (fluids); SCM old_val = scm_fluid_ref (fl); scm_fluid_set_x (fl, SCM_CAR (vals)); SCM_SETCAR (vals, old_val); fluids = SCM_CDR (fluids); vals = SCM_CDR (vals); } } /* Swap the fluid values in reverse order. This is important when the same fluid appears multiple times in the fluids list. */ void scm_swap_fluids_reverse (fluids, vals) SCM fluids, vals; { if (SCM_NIMP (fluids)) { SCM fl, old_val; scm_swap_fluids_reverse (SCM_CDR (fluids), SCM_CDR (vals)); fl = SCM_CAR (fluids); old_val = scm_fluid_ref (fl); scm_fluid_set_x (fl, SCM_CAR (vals)); SCM_SETCAR (vals, old_val); } } SCM_PROC (s_with_fluids, "with-fluids*", 3, 0, 0, scm_with_fluids); SCM scm_internal_with_fluids (fluids, vals, cproc, cdata) SCM fluids, vals; SCM (*cproc) (); void *cdata; { SCM ans; int flen = scm_ilength (fluids); int vlen = scm_ilength (vals); SCM_ASSERT (flen >= 0, fluids, SCM_ARG1, s_with_fluids); SCM_ASSERT (vlen >= 0, vals, SCM_ARG2, s_with_fluids); if (flen != vlen) scm_out_of_range (s_with_fluids, vals); scm_swap_fluids (fluids, vals); scm_dynwinds = scm_acons (fluids, vals, scm_dynwinds); ans = cproc (cdata); scm_dynwinds = SCM_CDR (scm_dynwinds); scm_swap_fluids_reverse (fluids, vals); return ans; } static SCM apply_thunk (void *thunk) { return scm_apply ((SCM) thunk, SCM_EOL, SCM_EOL); } SCM scm_with_fluids (fluids, vals, thunk) SCM fluids, vals, thunk; { return scm_internal_with_fluids (fluids, vals, apply_thunk, (void *)thunk); } void scm_init_fluids () { scm_tc16_fluid = scm_newsmob(&fluid_smob); #include "fluids.x" }