/* dl_vms.xs
*
* Platform: OpenVMS, VAX or AXP
* Author: Charles Bailey [email protected]
* Revised: 12-Dec-1994
*
* Implementation Note
* This section is added as an aid to users and DynaLoader developers, in
* order to clarify the process of dynamic linking under VMS.
* dl_vms.xs uses the supported VMS dynamic linking call, which allows
* a running program to map an arbitrary file of executable code and call
* routines within that file. This is done via the VMS RTL routine
* lib$find_image_symbol, whose calling sequence is as follows:
* status = lib$find_image_symbol(imgname,symname,symval,defspec);
* where
* status = a standard VMS status value (unsigned long int)
* imgname = a fixed-length string descriptor, passed by
* reference, containing the NAME ONLY of the image
* file to be mapped. An attempt will be made to
* translate this string as a logical name, so it may
* not contain any characters which are not allowed in
* logical names. If no translation is found, imgname
* is used directly as the name of the image file.
* symname = a fixed-length string descriptor, passed by
* reference, containing the name of the routine
* to be located.
* symval = an unsigned long int, passed by reference, into
* which is written the entry point address of the
* routine whose name is specified in symname.
* defspec = a fixed-length string descriptor, passed by
* reference, containing a default file specification
* whichis used to fill in any missing parts of the
* image file specification after the imgname argument
* is processed.
* In order to accommodate the handling of the imgname argument, the routine
* dl_expandspec() is provided for use by perl code (e.g. dl_findfile)
* which wants to see what image file lib$find_image_symbol would use if
* it were passed a given file specification. The file specification passed
* to dl_expandspec() and dl_load_file() can be partial or complete, and can
* use VMS or Unix syntax; these routines perform the necessary conversions.
* In general, writers of perl extensions need only conform to the
* procedures set out in the DynaLoader documentation, and let the details
* be taken care of by the routines here and in DynaLoader.pm. If anyone
* comes across any incompatibilities, please let me know. Thanks.
*
*/
#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"
/* N.B.:
* dl_debug and dl_last_error are static vars; you'll need to deal
* with them appropriately if you need context independence
*/
#include <descrip.h>
#include <fscndef.h>
#include <lib$routines.h>
#include <rms.h>
#include <ssdef.h>
#include <starlet.h>
#if defined(VMS_WE_ARE_CASE_SENSITIVE)
#define DL_CASE_SENSITIVE 1<<4
#else
#define DL_CASE_SENSITIVE 0
#endif
typedef unsigned long int vmssts;
struct libref {
struct dsc$descriptor_s name;
struct dsc$descriptor_s defspec;
};
typedef struct {
AV * x_require_symbols;
/* "Static" data for dl_expand_filespec() - This is static to save
* initialization on each call; if you need context-independence,
* just make these auto variables in dl_expandspec() and dl_load_file()
*/
char x_esa[NAM$C_MAXRSS];
char x_rsa[NAM$C_MAXRSS];
struct FAB x_fab;
struct NAM x_nam;
} my_cxtx_t; /* this *must* be named my_cxtx_t */
#define DL_CXT_EXTRA /* ask for dl_cxtx to be defined in dlutils.c */
#include "dlutils.c" /* dl_debug, dl_last_error; SaveError not used */
#define dl_require_symbols (dl_cxtx.x_require_symbols)
#define dl_esa (dl_cxtx.x_esa)
#define dl_rsa (dl_cxtx.x_rsa)
#define dl_fab (dl_cxtx.x_fab)
#define dl_nam (dl_cxtx.x_nam)
/* $PutMsg action routine - records error message in dl_last_error */
static vmssts
copy_errmsg(msg,unused)
struct dsc$descriptor_s * msg;
vmssts unused;
{
dTHX;
dMY_CXT;
if (*(msg->dsc$a_pointer) == '%') { /* first line */
if (dl_last_error)
strncpy((dl_last_error = saferealloc(dl_last_error,msg->dsc$w_length+1)),
msg->dsc$a_pointer, msg->dsc$w_length);
else
strncpy((dl_last_error = safemalloc(msg->dsc$w_length+1)),
msg->dsc$a_pointer, msg->dsc$w_length);
dl_last_error[msg->dsc$w_length] = '\0';
}
else { /* continuation line */
int errlen = strlen(dl_last_error);
dl_last_error = saferealloc(dl_last_error, errlen + msg->dsc$w_length + 2);
dl_last_error[errlen] = '\n'; dl_last_error[errlen+1] = '\0';
strncat(dl_last_error, msg->dsc$a_pointer, msg->dsc$w_length);
dl_last_error[errlen+msg->dsc$w_length+1] = '\0';
}
return 0;
}
/* Use $PutMsg to retrieve error message for failure status code */
static void
dl_set_error(sts,stv)
vmssts sts;
vmssts stv;
{
vmssts vec[3];
dTHX;
vec[0] = stv ? 2 : 1;
vec[1] = sts; vec[2] = stv;
_ckvmssts(sys$putmsg(vec,copy_errmsg,0,0));
}
static unsigned int
findsym_handler(void *sig, void *mech)
{
dTHX;
unsigned long int myvec[8],args, *usig = (unsigned long int *) sig;
/* Be paranoid and assume signal vector passed in might be readonly */
myvec[0] = args = usig[0] > 10 ? 9 : usig[0] - 1;
while (--args) myvec[args] = usig[args];
_ckvmssts(sys$putmsg(myvec,copy_errmsg,0,0));
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "findsym_handler: received\n\t%s\n",dl_last_error));
return SS$_CONTINUE;
}
/* wrapper for lib$find_image_symbol, so signalled errors can be saved
* for dl_error and then returned */
static unsigned long int
my_find_image_symbol(struct dsc$descriptor_s *imgname,
struct dsc$descriptor_s *symname,
void (**entry)(),
struct dsc$descriptor_s *defspec)
{
unsigned long int retsts;
VAXC$ESTABLISH(findsym_handler);
retsts = lib$find_image_symbol(imgname,symname,entry,defspec,DL_CASE_SENSITIVE);
return retsts;
}
static void
dl_private_init(pTHX)
{
dl_generic_private_init(aTHX);
{
dMY_CXT;
dl_require_symbols = get_av("DynaLoader::dl_require_symbols", 0x4);
/* Set up the static control blocks for dl_expand_filespec() */
dl_fab = cc$rms_fab;
dl_nam = cc$rms_nam;
dl_fab.fab$l_nam = &dl_nam;
dl_nam.nam$l_esa = dl_esa;
dl_nam.nam$b_ess = sizeof dl_esa;
dl_nam.nam$l_rsa = dl_rsa;
dl_nam.nam$b_rss = sizeof dl_rsa;
}
}
MODULE = DynaLoader PACKAGE = DynaLoader
BOOT:
(void)dl_private_init(aTHX);
void
dl_expandspec(filespec)
char * filespec
CODE:
char vmsspec[NAM$C_MAXRSS], defspec[NAM$C_MAXRSS];
size_t deflen;
vmssts sts;
dMY_CXT;
tovmsspec(filespec,vmsspec);
dl_fab.fab$l_fna = vmsspec;
dl_fab.fab$b_fns = strlen(vmsspec);
dl_fab.fab$l_dna = 0;
dl_fab.fab$b_dns = 0;
DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_expand_filespec(%s):\n",vmsspec));
/* On the first pass, just parse the specification string */
dl_nam.nam$b_nop = NAM$M_SYNCHK;
sts = sys$parse(&dl_fab);
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tSYNCHK sys$parse = %d\n",sts));
if (!(sts & 1)) {
dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv);
ST(0) = &PL_sv_undef;
}
else {
/* Now set up a default spec - everything but the name */
deflen = dl_nam.nam$l_name - dl_esa;
memcpy(defspec,dl_esa,deflen);
memcpy(defspec+deflen,dl_nam.nam$l_type,
dl_nam.nam$b_type + dl_nam.nam$b_ver);
deflen += dl_nam.nam$b_type + dl_nam.nam$b_ver;
memcpy(vmsspec,dl_nam.nam$l_name,dl_nam.nam$b_name);
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsplit filespec: name = %.*s, default = %.*s\n",
dl_nam.nam$b_name,vmsspec,deflen,defspec));
/* . . . and go back to expand it */
dl_nam.nam$b_nop = 0;
dl_fab.fab$l_dna = defspec;
dl_fab.fab$b_dns = deflen;
dl_fab.fab$b_fns = dl_nam.nam$b_name;
sts = sys$parse(&dl_fab);
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tname/default sys$parse = %d\n",sts));
if (!(sts & 1)) {
dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv);
ST(0) = &PL_sv_undef;
}
else {
/* Now find the actual file */
sts = sys$search(&dl_fab);
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsys$search = %d\n",sts));
if (!(sts & 1)) {
dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv);
ST(0) = &PL_sv_undef;
}
else {
ST(0) = sv_2mortal(newSVpvn(dl_nam.nam$l_rsa,dl_nam.nam$b_rsl));
DLDEBUG(1,PerlIO_printf(Perl_debug_log, "\tresult = \\%.*s\\\n",
dl_nam.nam$b_rsl,dl_nam.nam$l_rsa));
}
}
}
void
dl_load_file(filespec, flags)
char * filespec
int flags
PREINIT:
dTHX;
dMY_CXT;
char vmsspec[NAM$C_MAXRSS];
SV *reqSV, **reqSVhndl;
STRLEN deflen;
struct dsc$descriptor_s
specdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0},
symdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0};
struct fscnlst {
unsigned short int len;
unsigned short int code;
char *string;
} namlst[2] = {{0,FSCN$_NAME,0},{0,0,0}};
struct libref *dlptr;
vmssts sts, failed = 0;
void (*entry)();
CODE:
DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_load_file(%s,%x):\n", filespec,flags));
specdsc.dsc$a_pointer = tovmsspec(filespec,vmsspec);
specdsc.dsc$w_length = strlen(specdsc.dsc$a_pointer);
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tVMS-ified filespec is %s\n",
specdsc.dsc$a_pointer));
New(1399,dlptr,1,struct libref);
dlptr->name.dsc$b_dtype = dlptr->defspec.dsc$b_dtype = DSC$K_DTYPE_T;
dlptr->name.dsc$b_class = dlptr->defspec.dsc$b_class = DSC$K_CLASS_S;
sts = sys$filescan(&specdsc,namlst,0);
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsys$filescan: returns %d, name is %.*s\n",
sts,namlst[0].len,namlst[0].string));
if (!(sts & 1)) {
failed = 1;
dl_set_error(sts,0);
}
else {
dlptr->name.dsc$w_length = namlst[0].len;
dlptr->name.dsc$a_pointer = savepvn(namlst[0].string,namlst[0].len);
dlptr->defspec.dsc$w_length = specdsc.dsc$w_length - namlst[0].len;
New(1097, dlptr->defspec.dsc$a_pointer, dlptr->defspec.dsc$w_length + 1, char);
deflen = namlst[0].string - specdsc.dsc$a_pointer;
memcpy(dlptr->defspec.dsc$a_pointer,specdsc.dsc$a_pointer,deflen);
memcpy(dlptr->defspec.dsc$a_pointer + deflen,
namlst[0].string + namlst[0].len,
dlptr->defspec.dsc$w_length - deflen);
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlibref = name: %s, defspec: %.*s\n",
dlptr->name.dsc$a_pointer,
dlptr->defspec.dsc$w_length,
dlptr->defspec.dsc$a_pointer));
if (!(reqSVhndl = av_fetch(dl_require_symbols,0,FALSE)) || !(reqSV = *reqSVhndl)) {
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\t@dl_require_symbols empty, returning untested libref\n"));
}
else {
symdsc.dsc$w_length = SvCUR(reqSV);
symdsc.dsc$a_pointer = SvPVX(reqSV);
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\t$dl_require_symbols[0] = %.*s\n",
symdsc.dsc$w_length, symdsc.dsc$a_pointer));
sts = my_find_image_symbol(&(dlptr->name),&symdsc,
&entry,&(dlptr->defspec));
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlib$find_image_symbol returns %d\n",sts));
if (!(sts&1)) {
failed = 1;
dl_set_error(sts,0);
}
}
}
if (failed) {
Safefree(dlptr->name.dsc$a_pointer);
Safefree(dlptr->defspec.dsc$a_pointer);
Safefree(dlptr);
ST(0) = &PL_sv_undef;
}
else {
ST(0) = sv_2mortal(newSViv(PTR2IV(dlptr)));
}
void
dl_find_symbol(librefptr,symname)
void * librefptr
SV * symname
CODE:
struct libref thislib = *((struct libref *)librefptr);
struct dsc$descriptor_s
symdsc = {SvCUR(symname),DSC$K_DTYPE_T,DSC$K_CLASS_S,SvPVX(symname)};
void (*entry)();
vmssts sts;
DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_find_dymbol(%.*s,%.*s):\n",
thislib.name.dsc$w_length, thislib.name.dsc$a_pointer,
symdsc.dsc$w_length,symdsc.dsc$a_pointer));
sts = my_find_image_symbol(&(thislib.name),&symdsc,
&entry,&(thislib.defspec));
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlib$find_image_symbol returns %d\n",sts));
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tentry point is %d\n",
(unsigned long int) entry));
if (!(sts & 1)) {
/* error message already saved by findsym_handler */
ST(0) = &PL_sv_undef;
}
else ST(0) = sv_2mortal(newSViv(PTR2IV(entry)));
void
dl_undef_symbols()
PPCODE:
# These functions should not need changing on any platform:
void
dl_install_xsub(perl_name, symref, filename="$Package")
char * perl_name
void * symref
char * filename
CODE:
DLDEBUG(2,PerlIO_printf(Perl_debug_log, "dl_install_xsub(name=%s, symref=%x)\n",
perl_name, symref));
ST(0) = sv_2mortal(newRV((SV*)newXS(perl_name,
(void(*)(pTHX_ CV *))symref,
filename)));
char *
dl_error()
CODE:
dMY_CXT;
RETVAL = dl_last_error ;
OUTPUT:
RETVAL
# end.
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