/* Copyright (C) 1995, 1996, 1998, 1999, 2000, 2001, 2003, 2004, 2006, * 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc. * * This library 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. * * This library 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 this library; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA * 02110-1301 USA */ #ifdef HAVE_CONFIG_H # include #endif #include #include #include #include "libguile/_scm.h" #include "libguile/async.h" #include "libguile/goops.h" #include "libguile/instructions.h" #include "libguile/objcodes.h" #include "libguile/programs.h" #include "libguile/smob.h" #include "libguile/bdw-gc.h" #include /* scm_smobs scm_numsmob * implement a fixed sized array of smob records. * Indexes into this table are used when generating type * tags for smobjects (if you know a tag you can get an index and conversely). */ #define MAX_SMOB_COUNT SCM_I_MAX_SMOB_TYPE_COUNT long scm_numsmob; scm_smob_descriptor scm_smobs[MAX_SMOB_COUNT]; void scm_assert_smob_type (scm_t_bits tag, SCM val) { if (!SCM_SMOB_PREDICATE (tag, val)) scm_wrong_type_arg_msg (NULL, 0, val, scm_smobs[SCM_TC2SMOBNUM(tag)].name); } /* {Mark} */ /* This function is vestigial. It used to be the mark function's responsibility to set the mark bit on the smob or port, but now the generic marking routine in gc.c takes care of that, and a zero pointer for a mark function means "don't bother". So you never need scm_mark0. However, we leave it here because it's harmless to call it, and people out there have smob code that uses it, and there's no reason to make their links fail. */ SCM scm_mark0 (SCM ptr SCM_UNUSED) { return SCM_BOOL_F; } SCM /* Dirk::FIXME: The name markcdr is misleading, since the term cdr should only be used for real pairs. */ scm_markcdr (SCM ptr) { return SCM_CELL_OBJECT_1 (ptr); } /* {Free} */ size_t scm_free0 (SCM ptr SCM_UNUSED) { return 0; } /* {Print} */ int scm_smob_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED) { long n = SCM_SMOBNUM (exp); scm_puts ("#<", port); scm_puts (SCM_SMOBNAME (n) ? SCM_SMOBNAME (n) : "smob", port); scm_putc (' ', port); if (scm_smobs[n].size) scm_uintprint (SCM_CELL_WORD_1 (exp), 16, port); else scm_uintprint (SCM_UNPACK (exp), 16, port); scm_putc ('>', port); return 1; } /* {Apply} */ static SCM scm_smob_trampolines[16]; /* (nargs * nargs) + nopt + rest * (nargs + 1) */ #define SCM_SMOB_TRAMPOLINE(nreq,nopt,rest) \ scm_smob_trampolines[(nreq + nopt + rest) * (nreq + nopt + rest) \ + nopt + rest * (nreq + nopt + rest + 1)] static SCM apply_0 (SCM smob) { SCM (*subr)() = SCM_SMOB_DESCRIPTOR (smob).apply; return subr (smob); } static SCM apply_1 (SCM smob, SCM a) { SCM (*subr)() = SCM_SMOB_DESCRIPTOR (smob).apply; return subr (smob, a); } static SCM apply_2 (SCM smob, SCM a, SCM b) { SCM (*subr)() = SCM_SMOB_DESCRIPTOR (smob).apply; return subr (smob, a, b); } static SCM apply_3 (SCM smob, SCM a, SCM b, SCM c) { SCM (*subr)() = SCM_SMOB_DESCRIPTOR (smob).apply; return subr (smob, a, b, c); } static SCM scm_smob_trampoline (unsigned int nreq, unsigned int nopt, unsigned int rest) { SCM trampoline; if (SCM_UNLIKELY (rest > 1 || nreq + nopt + rest > 3)) scm_out_of_range ("make-smob", scm_from_uint (nreq + nopt + rest)); trampoline = SCM_SMOB_TRAMPOLINE (nreq, nopt, rest); if (SCM_LIKELY (SCM_UNPACK (trampoline))) return trampoline; switch (nreq + nopt + rest) { /* The + 1 is for the smob itself. */ case 0: trampoline = scm_c_make_gsubr ("apply-smob/0", nreq + 1, nopt, rest, apply_0); break; case 1: trampoline = scm_c_make_gsubr ("apply-smob/1", nreq + 1, nopt, rest, apply_1); break; case 2: trampoline = scm_c_make_gsubr ("apply-smob/2", nreq + 1, nopt, rest, apply_2); break; case 3: trampoline = scm_c_make_gsubr ("apply-smob/3", nreq + 1, nopt, rest, apply_3); break; default: abort (); } SCM_SMOB_TRAMPOLINE (nreq, nopt, rest) = trampoline; return trampoline; } scm_t_bits scm_make_smob_type (char const *name, size_t size) #define FUNC_NAME "scm_make_smob_type" { long new_smob; SCM_CRITICAL_SECTION_START; new_smob = scm_numsmob; if (scm_numsmob != MAX_SMOB_COUNT) ++scm_numsmob; SCM_CRITICAL_SECTION_END; if (new_smob == MAX_SMOB_COUNT) scm_misc_error (FUNC_NAME, "maximum number of smobs exceeded", SCM_EOL); scm_smobs[new_smob].name = name; scm_smobs[new_smob].size = size; /* Make a class object if Goops is present. */ if (SCM_UNPACK (scm_smob_class[0]) != 0) scm_smob_class[new_smob] = scm_make_extended_class (name, 0); return scm_tc7_smob + new_smob * 256; } #undef FUNC_NAME void scm_set_smob_mark (scm_t_bits tc, SCM (*mark) (SCM)) { scm_smobs[SCM_TC2SMOBNUM (tc)].mark = mark; } void scm_set_smob_free (scm_t_bits tc, size_t (*free) (SCM)) { scm_smobs[SCM_TC2SMOBNUM (tc)].free = free; } void scm_set_smob_print (scm_t_bits tc, int (*print) (SCM, SCM, scm_print_state*)) { scm_smobs[SCM_TC2SMOBNUM (tc)].print = print; } void scm_set_smob_equalp (scm_t_bits tc, SCM (*equalp) (SCM, SCM)) { scm_smobs[SCM_TC2SMOBNUM (tc)].equalp = equalp; } void scm_set_smob_apply (scm_t_bits tc, SCM (*apply) (), unsigned int req, unsigned int opt, unsigned int rst) { SCM trampoline = scm_smob_trampoline (req, opt, rst); scm_smobs[SCM_TC2SMOBNUM (tc)].apply = apply; /* In 2.2 this field is renamed to "apply_trampoline". */ scm_smobs[SCM_TC2SMOBNUM (tc)].apply_trampoline_objcode = trampoline; if (SCM_UNPACK (scm_smob_class[0]) != 0) scm_i_inherit_applicable (scm_smob_class[SCM_TC2SMOBNUM (tc)]); } SCM scm_make_smob (scm_t_bits tc) { scm_t_bits n = SCM_TC2SMOBNUM (tc); size_t size = scm_smobs[n].size; scm_t_bits data = (size > 0 ? (scm_t_bits) scm_gc_malloc (size, SCM_SMOBNAME (n)) : 0); SCM_RETURN_NEWSMOB (tc, data); } /* Marking SMOBs using user-supplied mark procedures. */ /* The GC kind used for SMOB types that provide a custom mark procedure. */ static int smob_gc_kind; /* Mark stack pointer and limit, used by `scm_gc_mark'. */ static scm_i_pthread_key_t current_mark_stack_pointer; static scm_i_pthread_key_t current_mark_stack_limit; /* The generic SMOB mark procedure that gets called for SMOBs allocated with smob_gc_kind. */ static struct GC_ms_entry * smob_mark (GC_word *addr, struct GC_ms_entry *mark_stack_ptr, struct GC_ms_entry *mark_stack_limit, GC_word env) { register SCM cell; register scm_t_bits tc, smobnum; cell = PTR2SCM (addr); if (SCM_TYP7 (cell) != scm_tc7_smob) /* It is likely that the GC passed us a pointer to a free-list element which we must ignore (see warning in `gc/gc_mark.h'). */ return mark_stack_ptr; tc = SCM_CELL_WORD_0 (cell); smobnum = SCM_TC2SMOBNUM (tc); if (smobnum >= scm_numsmob) /* The first word looks corrupt. */ abort (); mark_stack_ptr = GC_MARK_AND_PUSH (SCM2PTR (SCM_CELL_OBJECT_1 (cell)), mark_stack_ptr, mark_stack_limit, NULL); mark_stack_ptr = GC_MARK_AND_PUSH (SCM2PTR (SCM_CELL_OBJECT_2 (cell)), mark_stack_ptr, mark_stack_limit, NULL); mark_stack_ptr = GC_MARK_AND_PUSH (SCM2PTR (SCM_CELL_OBJECT_3 (cell)), mark_stack_ptr, mark_stack_limit, NULL); if (scm_smobs[smobnum].mark) { SCM obj; scm_i_pthread_setspecific (current_mark_stack_pointer, mark_stack_ptr); scm_i_pthread_setspecific (current_mark_stack_limit, mark_stack_limit); /* Invoke the SMOB's mark procedure, which will in turn invoke `scm_gc_mark', which may modify `current_mark_stack_pointer'. */ obj = scm_smobs[smobnum].mark (cell); mark_stack_ptr = scm_i_pthread_getspecific (current_mark_stack_pointer); if (SCM_NIMP (obj)) /* Mark the returned object. */ mark_stack_ptr = GC_MARK_AND_PUSH (SCM2PTR (obj), mark_stack_ptr, mark_stack_limit, NULL); scm_i_pthread_setspecific (current_mark_stack_pointer, NULL); scm_i_pthread_setspecific (current_mark_stack_limit, NULL); } return mark_stack_ptr; } /* Mark object O. We assume that this function is only called during the mark phase, i.e., from within `smob_mark' or one of its descendants. */ void scm_gc_mark (SCM o) { if (SCM_NIMP (o)) { void *mark_stack_ptr, *mark_stack_limit; mark_stack_ptr = scm_i_pthread_getspecific (current_mark_stack_pointer); mark_stack_limit = scm_i_pthread_getspecific (current_mark_stack_limit); if (mark_stack_ptr == NULL) /* The function was not called from a mark procedure. */ abort (); mark_stack_ptr = GC_MARK_AND_PUSH (SCM2PTR (o), mark_stack_ptr, mark_stack_limit, NULL); scm_i_pthread_setspecific (current_mark_stack_pointer, mark_stack_ptr); } } /* Finalize SMOB by calling its SMOB type's free function, if any. */ static void finalize_smob (void *ptr, void *data) { SCM smob; size_t (* free_smob) (SCM); smob = PTR2SCM (ptr); #if 0 printf ("finalizing SMOB %p (smobnum: %u)\n", ptr, SCM_SMOBNUM (smob)); #endif free_smob = scm_smobs[SCM_SMOBNUM (smob)].free; if (free_smob) free_smob (smob); } /* Return a SMOB with typecode TC. The SMOB type corresponding to TC may provide a custom mark procedure and it will be honored. */ SCM scm_i_new_smob (scm_t_bits tc, scm_t_bits data) { scm_t_bits smobnum = SCM_TC2SMOBNUM (tc); SCM ret; /* Use the smob_gc_kind if needed to allow the mark procedure to run. Since the marker only deals with double cells, that case allocates a double cell. We leave words 2 and 3 to there initial values, which is 0. */ if (scm_smobs [smobnum].mark) ret = PTR2SCM (GC_generic_malloc (2 * sizeof (scm_t_cell), smob_gc_kind)); else ret = PTR2SCM (GC_MALLOC (sizeof (scm_t_cell))); SCM_SET_CELL_WORD_1 (ret, data); SCM_SET_CELL_WORD_0 (ret, tc); if (scm_smobs[smobnum].free) scm_i_set_finalizer (SCM2PTR (ret), finalize_smob, NULL); return ret; } /* Return a SMOB with typecode TC. The SMOB type corresponding to TC may provide a custom mark procedure and it will be honored. */ SCM scm_i_new_double_smob (scm_t_bits tc, scm_t_bits data1, scm_t_bits data2, scm_t_bits data3) { scm_t_bits smobnum = SCM_TC2SMOBNUM (tc); SCM ret; /* Use the smob_gc_kind if needed to allow the mark procedure to run. */ if (scm_smobs [smobnum].mark) ret = PTR2SCM (GC_generic_malloc (2 * sizeof (scm_t_cell), smob_gc_kind)); else ret = PTR2SCM (GC_MALLOC (2 * sizeof (scm_t_cell))); SCM_SET_CELL_WORD_3 (ret, data3); SCM_SET_CELL_WORD_2 (ret, data2); SCM_SET_CELL_WORD_1 (ret, data1); SCM_SET_CELL_WORD_0 (ret, tc); if (scm_smobs[smobnum].free) scm_i_set_finalizer (SCM2PTR (ret), finalize_smob, NULL); return ret; } /* These two are internal details of the previous implementation of SCM_NEWSMOB and are no longer used. They are still here to preserve ABI stability in the 2.0 series. */ void scm_i_finalize_smob (void *ptr, void *data) { finalize_smob (ptr, data); } SCM scm_i_new_smob_with_mark_proc (scm_t_bits tc, scm_t_bits word1, scm_t_bits word2, scm_t_bits word3) { return scm_new_double_smob (tc, word1, word2, word3); } void scm_smob_prehistory () { long i; scm_i_pthread_key_create (¤t_mark_stack_pointer, NULL); scm_i_pthread_key_create (¤t_mark_stack_limit, NULL); smob_gc_kind = GC_new_kind (GC_new_free_list (), GC_MAKE_PROC (GC_new_proc (smob_mark), 0), 0, /* Clear new objects. As of version 7.1, libgc doesn't seem to support passing 0 here. */ 1); scm_numsmob = 0; for (i = 0; i < MAX_SMOB_COUNT; ++i) { scm_smobs[i].name = 0; scm_smobs[i].size = 0; scm_smobs[i].mark = 0; scm_smobs[i].free = 0; scm_smobs[i].print = scm_smob_print; scm_smobs[i].equalp = 0; scm_smobs[i].apply = 0; scm_smobs[i].apply_trampoline_objcode = SCM_BOOL_F; } } /* Local Variables: c-file-style: "gnu" End: */