1 /* dl_vms.xs 2 * 3 * Platform: OpenVMS, VAX or AXP or IA64 4 * Author: Charles Bailey bailey@newman.upenn.edu 5 * Revised: See http://public.activestate.com/cgi-bin/perlbrowse 6 * 7 * Implementation Note 8 * This section is added as an aid to users and DynaLoader developers, in 9 * order to clarify the process of dynamic linking under VMS. 10 * dl_vms.xs uses the supported VMS dynamic linking call, which allows 11 * a running program to map an arbitrary file of executable code and call 12 * routines within that file. This is done via the VMS RTL routine 13 * lib$find_image_symbol, whose calling sequence is as follows: 14 * status = lib$find_image_symbol(imgname,symname,symval,defspec); 15 * where 16 * status = a standard VMS status value (unsigned long int) 17 * imgname = a fixed-length string descriptor, passed by 18 * reference, containing the NAME ONLY of the image 19 * file to be mapped. An attempt will be made to 20 * translate this string as a logical name, so it may 21 * not contain any characters which are not allowed in 22 * logical names. If no translation is found, imgname 23 * is used directly as the name of the image file. 24 * symname = a fixed-length string descriptor, passed by 25 * reference, containing the name of the routine 26 * to be located. 27 * symval = an unsigned long int, passed by reference, into 28 * which is written the entry point address of the 29 * routine whose name is specified in symname. 30 * defspec = a fixed-length string descriptor, passed by 31 * reference, containing a default file specification 32 * whichis used to fill in any missing parts of the 33 * image file specification after the imgname argument 34 * is processed. 35 * In order to accommodate the handling of the imgname argument, the routine 36 * dl_expandspec() is provided for use by perl code (e.g. dl_findfile) 37 * which wants to see what image file lib$find_image_symbol would use if 38 * it were passed a given file specification. The file specification passed 39 * to dl_expandspec() and dl_load_file() can be partial or complete, and can 40 * use VMS or Unix syntax; these routines perform the necessary conversions. 41 * In general, writers of perl extensions need only conform to the 42 * procedures set out in the DynaLoader documentation, and let the details 43 * be taken care of by the routines here and in DynaLoader.pm. If anyone 44 * comes across any incompatibilities, please let me know. Thanks. 45 * 46 */ 47 48 #define PERL_EXT 49 #include "EXTERN.h" 50 #define PERL_IN_DL_VMS_XS 51 #include "perl.h" 52 #include "XSUB.h" 53 54 #include <descrip.h> 55 #include <fscndef.h> 56 #include <lib$routines.h> 57 #include <rms.h> 58 #include <ssdef.h> 59 #include <starlet.h> 60 61 #if defined(VMS_WE_ARE_CASE_SENSITIVE) 62 #define DL_CASE_SENSITIVE 1<<4 63 #else 64 #define DL_CASE_SENSITIVE 0 65 #endif 66 67 typedef unsigned long int vmssts; 68 69 struct libref { 70 struct dsc$descriptor_s name; 71 struct dsc$descriptor_s defspec; 72 }; 73 74 typedef struct { 75 AV * x_require_symbols; 76 /* "Static" data for dl_expand_filespec() - This is static to save 77 * initialization on each call; if you need context-independence, 78 * just make these auto variables in dl_expandspec() and dl_load_file() 79 */ 80 char x_esa[NAM$C_MAXRSS]; 81 char x_rsa[NAM$C_MAXRSS]; 82 struct FAB x_fab; 83 struct NAM x_nam; 84 } my_cxtx_t; /* this *must* be named my_cxtx_t */ 85 86 #define DL_CXT_EXTRA /* ask for dl_cxtx to be defined in dlutils.c */ 87 #include "dlutils.c" /* dl_debug, dl_last_error; SaveError not used */ 88 89 #define dl_require_symbols (dl_cxtx.x_require_symbols) 90 #define dl_esa (dl_cxtx.x_esa) 91 #define dl_rsa (dl_cxtx.x_rsa) 92 #define dl_fab (dl_cxtx.x_fab) 93 #define dl_nam (dl_cxtx.x_nam) 94 95 /* $PutMsg action routine - records error message in dl_last_error */ 96 static vmssts 97 copy_errmsg(struct dsc$descriptor_s *msg, vmssts unused) 98 { 99 dTHX; 100 dMY_CXT; 101 if (*(msg->dsc$a_pointer) == '%') { /* first line */ 102 sv_setpvn(MY_CXT.x_dl_last_error, msg->dsc$a_pointer, (STRLEN)msg->dsc$w_length); 103 } 104 else { /* continuation line */ 105 sv_catpvn(MY_CXT.x_dl_last_error, msg->dsc$a_pointer, (STRLEN)msg->dsc$w_length); 106 } 107 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "Saved error message: %s\n", dl_last_error)); 108 return 0; 109 } 110 111 /* Use $PutMsg to retrieve error message for failure status code */ 112 static void 113 dl_set_error(vmssts sts, vmssts stv) 114 { 115 vmssts vec[3]; 116 dTHX; 117 118 vec[0] = stv ? 2 : 1; 119 vec[1] = sts; vec[2] = stv; 120 _ckvmssts(sys$putmsg(vec,copy_errmsg,0,0)); 121 } 122 123 /* wrapper for lib$find_image_symbol, so signalled errors can be saved 124 * for dl_error and then returned */ 125 static unsigned long int 126 my_find_image_symbol(struct dsc$descriptor_s *imgname, 127 struct dsc$descriptor_s *symname, 128 void (**entry)(), 129 struct dsc$descriptor_s *defspec) 130 { 131 unsigned long int retsts; 132 VAXC$ESTABLISH((__vms_handler)lib$sig_to_ret); 133 retsts = lib$find_image_symbol(imgname,symname,entry,defspec,DL_CASE_SENSITIVE); 134 return retsts; 135 } 136 137 138 static void 139 dl_private_init(pTHX) 140 { 141 dl_generic_private_init(aTHX); 142 { 143 dMY_CXT; 144 dl_require_symbols = get_av("DynaLoader::dl_require_symbols", GV_ADDMULTI); 145 /* Set up the static control blocks for dl_expand_filespec() */ 146 dl_fab = cc$rms_fab; 147 dl_nam = cc$rms_nam; 148 dl_fab.fab$l_nam = &dl_nam; 149 dl_nam.nam$l_esa = dl_esa; 150 dl_nam.nam$b_ess = sizeof dl_esa; 151 dl_nam.nam$l_rsa = dl_rsa; 152 dl_nam.nam$b_rss = sizeof dl_rsa; 153 } 154 } 155 MODULE = DynaLoader PACKAGE = DynaLoader 156 157 BOOT: 158 (void)dl_private_init(aTHX); 159 160 void 161 dl_expandspec(filespec) 162 char * filespec 163 CODE: 164 char vmsspec[NAM$C_MAXRSS], defspec[NAM$C_MAXRSS]; 165 size_t deflen; 166 vmssts sts; 167 dMY_CXT; 168 169 tovmsspec(filespec,vmsspec); 170 dl_fab.fab$l_fna = vmsspec; 171 dl_fab.fab$b_fns = strlen(vmsspec); 172 dl_fab.fab$l_dna = 0; 173 dl_fab.fab$b_dns = 0; 174 DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_expand_filespec(%s):\n",vmsspec)); 175 /* On the first pass, just parse the specification string */ 176 dl_nam.nam$b_nop = NAM$M_SYNCHK; 177 sts = sys$parse(&dl_fab); 178 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tSYNCHK sys$parse = %d\n",sts)); 179 if (!(sts & 1)) { 180 dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv); 181 ST(0) = &PL_sv_undef; 182 } 183 else { 184 /* Now set up a default spec - everything but the name */ 185 deflen = dl_nam.nam$l_name - dl_esa; 186 memcpy(defspec,dl_esa,deflen); 187 memcpy(defspec+deflen,dl_nam.nam$l_type, 188 dl_nam.nam$b_type + dl_nam.nam$b_ver); 189 deflen += dl_nam.nam$b_type + dl_nam.nam$b_ver; 190 memcpy(vmsspec,dl_nam.nam$l_name,dl_nam.nam$b_name); 191 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsplit filespec: name = %.*s, default = %.*s\n", 192 dl_nam.nam$b_name,vmsspec,deflen,defspec)); 193 /* . . . and go back to expand it */ 194 dl_nam.nam$b_nop = 0; 195 dl_fab.fab$l_dna = defspec; 196 dl_fab.fab$b_dns = deflen; 197 dl_fab.fab$b_fns = dl_nam.nam$b_name; 198 sts = sys$parse(&dl_fab); 199 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tname/default sys$parse = %d\n",sts)); 200 if (!(sts & 1)) { 201 dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv); 202 ST(0) = &PL_sv_undef; 203 } 204 else { 205 /* Now find the actual file */ 206 sts = sys$search(&dl_fab); 207 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsys$search = %d\n",sts)); 208 if (!(sts & 1)) { 209 dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv); 210 ST(0) = &PL_sv_undef; 211 } 212 else { 213 ST(0) = sv_2mortal(newSVpvn(dl_nam.nam$l_rsa,dl_nam.nam$b_rsl)); 214 DLDEBUG(1,PerlIO_printf(Perl_debug_log, "\tresult = \\%.*s\\\n", 215 dl_nam.nam$b_rsl,dl_nam.nam$l_rsa)); 216 } 217 } 218 } 219 220 void 221 dl_load_file(filename, flags=0) 222 char * filename 223 int flags 224 PREINIT: 225 dTHX; 226 dMY_CXT; 227 char vmsspec[NAM$C_MAXRSS]; 228 SV *reqSV, **reqSVhndl; 229 STRLEN deflen; 230 struct dsc$descriptor_s 231 specdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0}, 232 symdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0}; 233 struct fscnlst { 234 unsigned short int len; 235 unsigned short int code; 236 char *string; 237 } namlst[2] = {{0,FSCN$_NAME,0},{0,0,0}}; 238 struct libref *dlptr; 239 vmssts sts, failed = 0; 240 void (*entry)(); 241 CODE: 242 243 DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_load_file(%s,%x):\n", filename,flags)); 244 specdsc.dsc$a_pointer = tovmsspec(filename,vmsspec); 245 specdsc.dsc$w_length = strlen(specdsc.dsc$a_pointer); 246 if (specdsc.dsc$w_length == 0) { /* undef in, empty out */ 247 XSRETURN_EMPTY; 248 } 249 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tVMS-ified filename is %s\n", 250 specdsc.dsc$a_pointer)); 251 Newx(dlptr,1,struct libref); 252 dlptr->name.dsc$b_dtype = dlptr->defspec.dsc$b_dtype = DSC$K_DTYPE_T; 253 dlptr->name.dsc$b_class = dlptr->defspec.dsc$b_class = DSC$K_CLASS_S; 254 sts = sys$filescan(&specdsc,namlst,0); 255 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsys$filescan: returns %d, name is %.*s\n", 256 sts,namlst[0].len,namlst[0].string)); 257 if (!(sts & 1)) { 258 failed = 1; 259 dl_set_error(sts,0); 260 } 261 else { 262 dlptr->name.dsc$w_length = namlst[0].len; 263 dlptr->name.dsc$a_pointer = savepvn(namlst[0].string,namlst[0].len); 264 dlptr->defspec.dsc$w_length = specdsc.dsc$w_length - namlst[0].len; 265 Newx(dlptr->defspec.dsc$a_pointer, dlptr->defspec.dsc$w_length + 1, char); 266 deflen = namlst[0].string - specdsc.dsc$a_pointer; 267 memcpy(dlptr->defspec.dsc$a_pointer,specdsc.dsc$a_pointer,deflen); 268 memcpy(dlptr->defspec.dsc$a_pointer + deflen, 269 namlst[0].string + namlst[0].len, 270 dlptr->defspec.dsc$w_length - deflen); 271 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlibref = name: %s, defspec: %.*s\n", 272 dlptr->name.dsc$a_pointer, 273 dlptr->defspec.dsc$w_length, 274 dlptr->defspec.dsc$a_pointer)); 275 if (!(reqSVhndl = av_fetch(dl_require_symbols,0,FALSE)) || !(reqSV = *reqSVhndl)) { 276 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\t@dl_require_symbols empty, returning untested libref\n")); 277 } 278 else { 279 symdsc.dsc$w_length = SvCUR(reqSV); 280 symdsc.dsc$a_pointer = SvPVX(reqSV); 281 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\t$dl_require_symbols[0] = %.*s\n", 282 symdsc.dsc$w_length, symdsc.dsc$a_pointer)); 283 sts = my_find_image_symbol(&(dlptr->name),&symdsc, 284 &entry,&(dlptr->defspec)); 285 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlib$find_image_symbol returns %d\n",sts)); 286 if (!(sts&1)) { 287 failed = 1; 288 dl_set_error(sts,0); 289 } 290 } 291 } 292 293 if (failed) { 294 Safefree(dlptr->name.dsc$a_pointer); 295 Safefree(dlptr->defspec.dsc$a_pointer); 296 Safefree(dlptr); 297 ST(0) = &PL_sv_undef; 298 } 299 else { 300 ST(0) = sv_2mortal(newSViv(PTR2IV(dlptr))); 301 } 302 303 304 void 305 dl_find_symbol(librefptr,symname,ign_err=0) 306 void * librefptr 307 SV * symname 308 int ign_err 309 PREINIT: 310 struct libref thislib = *((struct libref *)librefptr); 311 struct dsc$descriptor_s 312 symdsc = {SvCUR(symname),DSC$K_DTYPE_T,DSC$K_CLASS_S,SvPVX(symname)}; 313 void (*entry)(); 314 vmssts sts; 315 CODE: 316 317 DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_find_symbol(%.*s,%.*s):\n", 318 thislib.name.dsc$w_length, thislib.name.dsc$a_pointer, 319 symdsc.dsc$w_length,symdsc.dsc$a_pointer)); 320 sts = my_find_image_symbol(&(thislib.name),&symdsc, 321 &entry,&(thislib.defspec)); 322 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlib$find_image_symbol returns %d\n",sts)); 323 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tentry point is %d\n", 324 (unsigned long int) entry)); 325 if (!(sts & 1)) { 326 if (!ign_err) dl_set_error(sts,0); 327 ST(0) = &PL_sv_undef; 328 } 329 else ST(0) = sv_2mortal(newSViv(PTR2IV(entry))); 330 331 332 void 333 dl_undef_symbols() 334 PPCODE: 335 336 337 # These functions should not need changing on any platform: 338 339 void 340 dl_install_xsub(perl_name, symref, filename="$Package") 341 char * perl_name 342 void * symref 343 const char * filename 344 CODE: 345 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "dl_install_xsub(name=%s, symref=%x)\n", 346 perl_name, symref)); 347 ST(0) = sv_2mortal(newRV((SV*)newXS_flags(perl_name, 348 (void(*)(pTHX_ CV *))symref, 349 filename, NULL, 350 XS_DYNAMIC_FILENAME))); 351 352 353 SV * 354 dl_error() 355 CODE: 356 dMY_CXT; 357 RETVAL = newSVsv(MY_CXT.x_dl_last_error); 358 OUTPUT: 359 RETVAL 360 361 #if defined(USE_ITHREADS) 362 363 void 364 CLONE(...) 365 CODE: 366 MY_CXT_CLONE; 367 368 PERL_UNUSED_VAR(items); 369 370 /* MY_CXT_CLONE just does a memcpy on the whole structure, so to avoid 371 * using Perl variables that belong to another thread, we create our 372 * own for this thread. 373 */ 374 MY_CXT.x_dl_last_error = newSVpvs(""); 375 dl_require_symbols = get_av("DynaLoader::dl_require_symbols", GV_ADDMULTI); 376 377 /* Set up the "static" control blocks for dl_expand_filespec() */ 378 dl_fab = cc$rms_fab; 379 dl_nam = cc$rms_nam; 380 dl_fab.fab$l_nam = &dl_nam; 381 dl_nam.nam$l_esa = dl_esa; 382 dl_nam.nam$b_ess = sizeof dl_esa; 383 dl_nam.nam$l_rsa = dl_rsa; 384 dl_nam.nam$b_rss = sizeof dl_rsa; 385 386 #endif 387 388 # end. 389