freebsd-dev/contrib/perl5/ext/Opcode/Opcode.xs
2000-06-25 11:04:01 +00:00

478 lines
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#define PERL_NO_GET_CONTEXT
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
/* PL_maxo shouldn't differ from MAXO but leave room anyway (see BOOT:) */
#define OP_MASK_BUF_SIZE (MAXO + 100)
/* XXX op_named_bits and opset_all are never freed */
static HV *op_named_bits; /* cache shared for whole process */
static SV *opset_all; /* mask with all bits set */
static IV opset_len; /* length of opmasks in bytes */
static int opcode_debug = 0;
static SV *new_opset (pTHX_ SV *old_opset);
static int verify_opset (pTHX_ SV *opset, int fatal);
static void set_opset_bits (pTHX_ char *bitmap, SV *bitspec, int on, char *opname);
static void put_op_bitspec (pTHX_ char *optag, STRLEN len, SV *opset);
static SV *get_op_bitspec (pTHX_ char *opname, STRLEN len, int fatal);
/* Initialise our private op_named_bits HV.
* It is first loaded with the name and number of each perl operator.
* Then the builtin tags :none and :all are added.
* Opcode.pm loads the standard optags from __DATA__
* XXX leak-alert: data allocated here is never freed, call this
* at most once
*/
static void
op_names_init(pTHX)
{
int i;
STRLEN len;
char **op_names;
char *bitmap;
op_named_bits = newHV();
op_names = get_op_names();
for(i=0; i < PL_maxo; ++i) {
SV *sv;
sv = newSViv(i);
SvREADONLY_on(sv);
hv_store(op_named_bits, op_names[i], strlen(op_names[i]), sv, 0);
}
put_op_bitspec(aTHX_ ":none",0, sv_2mortal(new_opset(aTHX_ Nullsv)));
opset_all = new_opset(aTHX_ Nullsv);
bitmap = SvPV(opset_all, len);
i = len-1; /* deal with last byte specially, see below */
while(i-- > 0)
bitmap[i] = 0xFF;
/* Take care to set the right number of bits in the last byte */
bitmap[len-1] = (PL_maxo & 0x07) ? ~(0xFF << (PL_maxo & 0x07)) : 0xFF;
put_op_bitspec(aTHX_ ":all",0, opset_all); /* don't mortalise */
}
/* Store a new tag definition. Always a mask.
* The tag must not already be defined.
* SV *mask is copied not referenced.
*/
static void
put_op_bitspec(pTHX_ char *optag, STRLEN len, SV *mask)
{
SV **svp;
verify_opset(aTHX_ mask,1);
if (!len)
len = strlen(optag);
svp = hv_fetch(op_named_bits, optag, len, 1);
if (SvOK(*svp))
croak("Opcode tag \"%s\" already defined", optag);
sv_setsv(*svp, mask);
SvREADONLY_on(*svp);
}
/* Fetch a 'bits' entry for an opname or optag (IV/PV).
* Note that we return the actual entry for speed.
* Always sv_mortalcopy() if returing it to user code.
*/
static SV *
get_op_bitspec(pTHX_ char *opname, STRLEN len, int fatal)
{
SV **svp;
if (!len)
len = strlen(opname);
svp = hv_fetch(op_named_bits, opname, len, 0);
if (!svp || !SvOK(*svp)) {
if (!fatal)
return Nullsv;
if (*opname == ':')
croak("Unknown operator tag \"%s\"", opname);
if (*opname == '!') /* XXX here later, or elsewhere? */
croak("Can't negate operators here (\"%s\")", opname);
if (isALPHA(*opname))
croak("Unknown operator name \"%s\"", opname);
croak("Unknown operator prefix \"%s\"", opname);
}
return *svp;
}
static SV *
new_opset(pTHX_ SV *old_opset)
{
SV *opset;
if (old_opset) {
verify_opset(aTHX_ old_opset,1);
opset = newSVsv(old_opset);
}
else {
opset = NEWSV(1156, opset_len);
Zero(SvPVX(opset), opset_len + 1, char);
SvCUR_set(opset, opset_len);
(void)SvPOK_only(opset);
}
/* not mortalised here */
return opset;
}
static int
verify_opset(pTHX_ SV *opset, int fatal)
{
char *err = Nullch;
if (!SvOK(opset)) err = "undefined";
else if (!SvPOK(opset)) err = "wrong type";
else if (SvCUR(opset) != opset_len) err = "wrong size";
if (err && fatal) {
croak("Invalid opset: %s", err);
}
return !err;
}
static void
set_opset_bits(pTHX_ char *bitmap, SV *bitspec, int on, char *opname)
{
if (SvIOK(bitspec)) {
int myopcode = SvIV(bitspec);
int offset = myopcode >> 3;
int bit = myopcode & 0x07;
if (myopcode >= PL_maxo || myopcode < 0)
croak("panic: opcode \"%s\" value %d is invalid", opname, myopcode);
if (opcode_debug >= 2)
warn("set_opset_bits bit %2d (off=%d, bit=%d) %s %s\n",
myopcode, offset, bit, opname, (on)?"on":"off");
if (on)
bitmap[offset] |= 1 << bit;
else
bitmap[offset] &= ~(1 << bit);
}
else if (SvPOK(bitspec) && SvCUR(bitspec) == opset_len) {
STRLEN len;
char *specbits = SvPV(bitspec, len);
if (opcode_debug >= 2)
warn("set_opset_bits opset %s %s\n", opname, (on)?"on":"off");
if (on)
while(len-- > 0) bitmap[len] |= specbits[len];
else
while(len-- > 0) bitmap[len] &= ~specbits[len];
}
else
croak("panic: invalid bitspec for \"%s\" (type %u)",
opname, (unsigned)SvTYPE(bitspec));
}
static void
opmask_add(pTHX_ SV *opset) /* THE ONLY FUNCTION TO EDIT PL_op_mask ITSELF */
{
int i,j;
char *bitmask;
STRLEN len;
int myopcode = 0;
verify_opset(aTHX_ opset,1); /* croaks on bad opset */
if (!PL_op_mask) /* caller must ensure PL_op_mask exists */
croak("Can't add to uninitialised PL_op_mask");
/* OPCODES ALREADY MASKED ARE NEVER UNMASKED. See opmask_addlocal() */
bitmask = SvPV(opset, len);
for (i=0; i < opset_len; i++) {
U16 bits = bitmask[i];
if (!bits) { /* optimise for sparse masks */
myopcode += 8;
continue;
}
for (j=0; j < 8 && myopcode < PL_maxo; )
PL_op_mask[myopcode++] |= bits & (1 << j++);
}
}
static void
opmask_addlocal(pTHX_ SV *opset, char *op_mask_buf) /* Localise PL_op_mask then opmask_add() */
{
char *orig_op_mask = PL_op_mask;
SAVEVPTR(PL_op_mask);
#if !defined(PERL_OBJECT)
/* XXX casting to an ordinary function ptr from a member function ptr
* is disallowed by Borland
*/
if (opcode_debug >= 2)
SAVEDESTRUCTOR((void(*)(void*))Perl_warn,"PL_op_mask restored");
#endif
PL_op_mask = &op_mask_buf[0];
if (orig_op_mask)
Copy(orig_op_mask, PL_op_mask, PL_maxo, char);
else
Zero(PL_op_mask, PL_maxo, char);
opmask_add(aTHX_ opset);
}
MODULE = Opcode PACKAGE = Opcode
PROTOTYPES: ENABLE
BOOT:
assert(PL_maxo < OP_MASK_BUF_SIZE);
opset_len = (PL_maxo + 7) / 8;
if (opcode_debug >= 1)
warn("opset_len %ld\n", (long)opset_len);
op_names_init(aTHX);
void
_safe_call_sv(Package, mask, codesv)
char * Package
SV * mask
SV * codesv
PPCODE:
char op_mask_buf[OP_MASK_BUF_SIZE];
GV *gv;
ENTER;
opmask_addlocal(aTHX_ mask, op_mask_buf);
save_aptr(&PL_endav);
PL_endav = (AV*)sv_2mortal((SV*)newAV()); /* ignore END blocks for now */
save_hptr(&PL_defstash); /* save current default stack */
/* the assignment to global defstash changes our sense of 'main' */
PL_defstash = gv_stashpv(Package, GV_ADDWARN); /* should exist already */
save_hptr(&PL_curstash);
PL_curstash = PL_defstash;
/* defstash must itself contain a main:: so we'll add that now */
/* take care with the ref counts (was cause of long standing bug) */
/* XXX I'm still not sure if this is right, GV_ADDWARN should warn! */
gv = gv_fetchpv("main::", GV_ADDWARN, SVt_PVHV);
sv_free((SV*)GvHV(gv));
GvHV(gv) = (HV*)SvREFCNT_inc(PL_defstash);
PUSHMARK(SP);
perl_call_sv(codesv, GIMME|G_EVAL|G_KEEPERR); /* use callers context */
SPAGAIN; /* for the PUTBACK added by xsubpp */
LEAVE;
int
verify_opset(opset, fatal = 0)
SV *opset
int fatal
CODE:
RETVAL = verify_opset(aTHX_ opset,fatal);
OUTPUT:
RETVAL
void
invert_opset(opset)
SV *opset
CODE:
{
char *bitmap;
STRLEN len = opset_len;
opset = sv_2mortal(new_opset(aTHX_ opset)); /* verify and clone opset */
bitmap = SvPVX(opset);
while(len-- > 0)
bitmap[len] = ~bitmap[len];
/* take care of extra bits beyond PL_maxo in last byte */
if (PL_maxo & 07)
bitmap[opset_len-1] &= ~(0xFF << (PL_maxo & 0x07));
}
ST(0) = opset;
void
opset_to_ops(opset, desc = 0)
SV *opset
int desc
PPCODE:
{
STRLEN len;
int i, j, myopcode;
char *bitmap = SvPV(opset, len);
char **names = (desc) ? get_op_descs() : get_op_names();
verify_opset(aTHX_ opset,1);
for (myopcode=0, i=0; i < opset_len; i++) {
U16 bits = bitmap[i];
for (j=0; j < 8 && myopcode < PL_maxo; j++, myopcode++) {
if ( bits & (1 << j) )
XPUSHs(sv_2mortal(newSVpv(names[myopcode], 0)));
}
}
}
void
opset(...)
CODE:
int i, j;
SV *bitspec, *opset;
char *bitmap;
STRLEN len, on;
opset = sv_2mortal(new_opset(aTHX_ Nullsv));
bitmap = SvPVX(opset);
for (i = 0; i < items; i++) {
char *opname;
on = 1;
if (verify_opset(aTHX_ ST(i),0)) {
opname = "(opset)";
bitspec = ST(i);
}
else {
opname = SvPV(ST(i), len);
if (*opname == '!') { on=0; ++opname;--len; }
bitspec = get_op_bitspec(aTHX_ opname, len, 1);
}
set_opset_bits(aTHX_ bitmap, bitspec, on, opname);
}
ST(0) = opset;
#define PERMITING (ix == 0 || ix == 1)
#define ONLY_THESE (ix == 0 || ix == 2)
void
permit_only(safe, ...)
SV *safe
ALIAS:
permit = 1
deny_only = 2
deny = 3
CODE:
int i, on;
SV *bitspec, *mask;
char *bitmap, *opname;
STRLEN len;
if (!SvROK(safe) || !SvOBJECT(SvRV(safe)) || SvTYPE(SvRV(safe))!=SVt_PVHV)
croak("Not a Safe object");
mask = *hv_fetch((HV*)SvRV(safe), "Mask",4, 1);
if (ONLY_THESE) /* *_only = new mask, else edit current */
sv_setsv(mask, sv_2mortal(new_opset(aTHX_ PERMITING ? opset_all : Nullsv)));
else
verify_opset(aTHX_ mask,1); /* croaks */
bitmap = SvPVX(mask);
for (i = 1; i < items; i++) {
on = PERMITING ? 0 : 1; /* deny = mask bit on */
if (verify_opset(aTHX_ ST(i),0)) { /* it's a valid mask */
opname = "(opset)";
bitspec = ST(i);
}
else { /* it's an opname/optag */
opname = SvPV(ST(i), len);
/* invert if op has ! prefix (only one allowed) */
if (*opname == '!') { on = !on; ++opname; --len; }
bitspec = get_op_bitspec(aTHX_ opname, len, 1); /* croaks */
}
set_opset_bits(aTHX_ bitmap, bitspec, on, opname);
}
ST(0) = &PL_sv_yes;
void
opdesc(...)
PPCODE:
int i, myopcode;
STRLEN len;
SV **args;
char **op_desc = get_op_descs();
/* copy args to a scratch area since we may push output values onto */
/* the stack faster than we read values off it if masks are used. */
args = (SV**)SvPVX(sv_2mortal(newSVpvn((char*)&ST(0), items*sizeof(SV*))));
for (i = 0; i < items; i++) {
char *opname = SvPV(args[i], len);
SV *bitspec = get_op_bitspec(aTHX_ opname, len, 1);
if (SvIOK(bitspec)) {
myopcode = SvIV(bitspec);
if (myopcode < 0 || myopcode >= PL_maxo)
croak("panic: opcode %d (%s) out of range",myopcode,opname);
XPUSHs(sv_2mortal(newSVpv(op_desc[myopcode], 0)));
}
else if (SvPOK(bitspec) && SvCUR(bitspec) == opset_len) {
int b, j;
STRLEN n_a;
char *bitmap = SvPV(bitspec,n_a);
myopcode = 0;
for (b=0; b < opset_len; b++) {
U16 bits = bitmap[b];
for (j=0; j < 8 && myopcode < PL_maxo; j++, myopcode++)
if (bits & (1 << j))
XPUSHs(sv_2mortal(newSVpv(op_desc[myopcode], 0)));
}
}
else
croak("panic: invalid bitspec for \"%s\" (type %u)",
opname, (unsigned)SvTYPE(bitspec));
}
void
define_optag(optagsv, mask)
SV *optagsv
SV *mask
CODE:
STRLEN len;
char *optag = SvPV(optagsv, len);
put_op_bitspec(aTHX_ optag, len, mask); /* croaks */
ST(0) = &PL_sv_yes;
void
empty_opset()
CODE:
ST(0) = sv_2mortal(new_opset(aTHX_ Nullsv));
void
full_opset()
CODE:
ST(0) = sv_2mortal(new_opset(aTHX_ opset_all));
void
opmask_add(opset)
SV *opset
PREINIT:
if (!PL_op_mask)
Newz(0, PL_op_mask, PL_maxo, char);
CODE:
opmask_add(aTHX_ opset);
void
opcodes()
PPCODE:
if (GIMME == G_ARRAY) {
croak("opcodes in list context not yet implemented"); /* XXX */
}
else {
XPUSHs(sv_2mortal(newSViv(PL_maxo)));
}
void
opmask()
CODE:
ST(0) = sv_2mortal(new_opset(aTHX_ Nullsv));
if (PL_op_mask) {
char *bitmap = SvPVX(ST(0));
int myopcode;
for(myopcode=0; myopcode < PL_maxo; ++myopcode) {
if (PL_op_mask[myopcode])
bitmap[myopcode >> 3] |= 1 << (myopcode & 0x07);
}
}