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
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);
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
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
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$find_image_symbol would use if
38 * it were passed a given file specification. The file specification passed
39 * to dl_expandspec() and dl_load_file() can be partial or complete, and can
40 * use VMS or Unix syntax; these routines perform the necessary conversions.
41 * In general, writers of perl extensions need only conform to the
42 * procedures set out in the DynaLoader documentation, and let the details
43 * be taken care of by the routines here and in DynaLoader.pm. If anyone
44 * comes across any incompatibilities, please let me know. Thanks.
54 #include <lib$routines.h>
59 #if defined(VMS_WE_ARE_CASE_SENSITIVE)
60 #define DL_CASE_SENSITIVE 1<<4
62 #define DL_CASE_SENSITIVE 0
65 typedef unsigned long int vmssts;
68 struct dsc$descriptor_s name;
69 struct dsc$descriptor_s defspec;
73 AV * x_require_symbols;
74 /* "Static" data for dl_expand_filespec() - This is static to save
75 * initialization on each call; if you need context-independence,
76 * just make these auto variables in dl_expandspec() and dl_load_file()
78 char x_esa[NAM$C_MAXRSS];
79 char x_rsa[NAM$C_MAXRSS];
82 } my_cxtx_t; /* this *must* be named my_cxtx_t */
84 #define DL_CXT_EXTRA /* ask for dl_cxtx to be defined in dlutils.c */
85 #include "dlutils.c" /* dl_debug, dl_last_error; SaveError not used */
87 #define dl_require_symbols (dl_cxtx.x_require_symbols)
88 #define dl_esa (dl_cxtx.x_esa)
89 #define dl_rsa (dl_cxtx.x_rsa)
90 #define dl_fab (dl_cxtx.x_fab)
91 #define dl_nam (dl_cxtx.x_nam)
93 /* $PutMsg action routine - records error message in dl_last_error */
95 copy_errmsg(struct dsc$descriptor_s *msg, vmssts unused)
99 if (*(msg->dsc$a_pointer) == '%') { /* first line */
100 sv_setpvn(MY_CXT.x_dl_last_error, msg->dsc$a_pointer, (STRLEN)msg->dsc$w_length);
102 else { /* continuation line */
103 sv_catpvn(MY_CXT.x_dl_last_error, msg->dsc$a_pointer, (STRLEN)msg->dsc$w_length);
105 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "Saved error message: %s\n", dl_last_error));
109 /* Use $PutMsg to retrieve error message for failure status code */
111 dl_set_error(vmssts sts, vmssts stv)
116 vec[0] = stv ? 2 : 1;
117 vec[1] = sts; vec[2] = stv;
118 _ckvmssts(sys$putmsg(vec,copy_errmsg,0,0));
121 /* wrapper for lib$find_image_symbol, so signalled errors can be saved
122 * for dl_error and then returned */
123 static unsigned long int
124 my_find_image_symbol(struct dsc$descriptor_s *imgname,
125 struct dsc$descriptor_s *symname,
127 struct dsc$descriptor_s *defspec)
129 unsigned long int retsts;
130 VAXC$ESTABLISH(lib$sig_to_ret);
131 retsts = lib$find_image_symbol(imgname,symname,entry,defspec,DL_CASE_SENSITIVE);
137 dl_private_init(pTHX)
139 dl_generic_private_init(aTHX);
142 dl_require_symbols = get_av("DynaLoader::dl_require_symbols", GV_ADDMULTI);
143 /* Set up the static control blocks for dl_expand_filespec() */
146 dl_fab.fab$l_nam = &dl_nam;
147 dl_nam.nam$l_esa = dl_esa;
148 dl_nam.nam$b_ess = sizeof dl_esa;
149 dl_nam.nam$l_rsa = dl_rsa;
150 dl_nam.nam$b_rss = sizeof dl_rsa;
153 MODULE = DynaLoader PACKAGE = DynaLoader
156 (void)dl_private_init(aTHX);
159 dl_expandspec(filespec)
162 char vmsspec[NAM$C_MAXRSS], defspec[NAM$C_MAXRSS];
167 tovmsspec(filespec,vmsspec);
168 dl_fab.fab$l_fna = vmsspec;
169 dl_fab.fab$b_fns = strlen(vmsspec);
170 dl_fab.fab$l_dna = 0;
171 dl_fab.fab$b_dns = 0;
172 DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_expand_filespec(%s):\n",vmsspec));
173 /* On the first pass, just parse the specification string */
174 dl_nam.nam$b_nop = NAM$M_SYNCHK;
175 sts = sys$parse(&dl_fab);
176 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tSYNCHK sys$parse = %d\n",sts));
178 dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv);
179 ST(0) = &PL_sv_undef;
182 /* Now set up a default spec - everything but the name */
183 deflen = dl_nam.nam$l_name - dl_esa;
184 memcpy(defspec,dl_esa,deflen);
185 memcpy(defspec+deflen,dl_nam.nam$l_type,
186 dl_nam.nam$b_type + dl_nam.nam$b_ver);
187 deflen += dl_nam.nam$b_type + dl_nam.nam$b_ver;
188 memcpy(vmsspec,dl_nam.nam$l_name,dl_nam.nam$b_name);
189 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsplit filespec: name = %.*s, default = %.*s\n",
190 dl_nam.nam$b_name,vmsspec,deflen,defspec));
191 /* . . . and go back to expand it */
192 dl_nam.nam$b_nop = 0;
193 dl_fab.fab$l_dna = defspec;
194 dl_fab.fab$b_dns = deflen;
195 dl_fab.fab$b_fns = dl_nam.nam$b_name;
196 sts = sys$parse(&dl_fab);
197 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tname/default sys$parse = %d\n",sts));
199 dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv);
200 ST(0) = &PL_sv_undef;
203 /* Now find the actual file */
204 sts = sys$search(&dl_fab);
205 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsys$search = %d\n",sts));
207 dl_set_error(dl_fab.fab$l_sts,dl_fab.fab$l_stv);
208 ST(0) = &PL_sv_undef;
211 ST(0) = sv_2mortal(newSVpvn(dl_nam.nam$l_rsa,dl_nam.nam$b_rsl));
212 DLDEBUG(1,PerlIO_printf(Perl_debug_log, "\tresult = \\%.*s\\\n",
213 dl_nam.nam$b_rsl,dl_nam.nam$l_rsa));
219 dl_load_file(filename, flags=0)
225 char vmsspec[NAM$C_MAXRSS];
226 SV *reqSV, **reqSVhndl;
228 struct dsc$descriptor_s
229 specdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0},
230 symdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0};
232 unsigned short int len;
233 unsigned short int code;
235 } namlst[2] = {{0,FSCN$_NAME,0},{0,0,0}};
236 struct libref *dlptr;
237 vmssts sts, failed = 0;
241 DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_load_file(%s,%x):\n", filename,flags));
242 specdsc.dsc$a_pointer = tovmsspec(filename,vmsspec);
243 specdsc.dsc$w_length = strlen(specdsc.dsc$a_pointer);
244 if (specdsc.dsc$w_length == 0) { /* undef in, empty out */
247 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tVMS-ified filename is %s\n",
248 specdsc.dsc$a_pointer));
249 Newx(dlptr,1,struct libref);
250 dlptr->name.dsc$b_dtype = dlptr->defspec.dsc$b_dtype = DSC$K_DTYPE_T;
251 dlptr->name.dsc$b_class = dlptr->defspec.dsc$b_class = DSC$K_CLASS_S;
252 sts = sys$filescan(&specdsc,namlst,0);
253 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tsys$filescan: returns %d, name is %.*s\n",
254 sts,namlst[0].len,namlst[0].string));
260 dlptr->name.dsc$w_length = namlst[0].len;
261 dlptr->name.dsc$a_pointer = savepvn(namlst[0].string,namlst[0].len);
262 dlptr->defspec.dsc$w_length = specdsc.dsc$w_length - namlst[0].len;
263 Newx(dlptr->defspec.dsc$a_pointer, dlptr->defspec.dsc$w_length + 1, char);
264 deflen = namlst[0].string - specdsc.dsc$a_pointer;
265 memcpy(dlptr->defspec.dsc$a_pointer,specdsc.dsc$a_pointer,deflen);
266 memcpy(dlptr->defspec.dsc$a_pointer + deflen,
267 namlst[0].string + namlst[0].len,
268 dlptr->defspec.dsc$w_length - deflen);
269 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlibref = name: %s, defspec: %.*s\n",
270 dlptr->name.dsc$a_pointer,
271 dlptr->defspec.dsc$w_length,
272 dlptr->defspec.dsc$a_pointer));
273 if (!(reqSVhndl = av_fetch(dl_require_symbols,0,FALSE)) || !(reqSV = *reqSVhndl)) {
274 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\t@dl_require_symbols empty, returning untested libref\n"));
277 symdsc.dsc$w_length = SvCUR(reqSV);
278 symdsc.dsc$a_pointer = SvPVX(reqSV);
279 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\t$dl_require_symbols[0] = %.*s\n",
280 symdsc.dsc$w_length, symdsc.dsc$a_pointer));
281 sts = my_find_image_symbol(&(dlptr->name),&symdsc,
282 &entry,&(dlptr->defspec));
283 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlib$find_image_symbol returns %d\n",sts));
292 Safefree(dlptr->name.dsc$a_pointer);
293 Safefree(dlptr->defspec.dsc$a_pointer);
295 ST(0) = &PL_sv_undef;
298 ST(0) = sv_2mortal(newSViv(PTR2IV(dlptr)));
303 dl_find_symbol(librefptr,symname)
307 struct libref thislib = *((struct libref *)librefptr);
308 struct dsc$descriptor_s
309 symdsc = {SvCUR(symname),DSC$K_DTYPE_T,DSC$K_CLASS_S,SvPVX(symname)};
313 DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_find_symbol(%.*s,%.*s):\n",
314 thislib.name.dsc$w_length, thislib.name.dsc$a_pointer,
315 symdsc.dsc$w_length,symdsc.dsc$a_pointer));
316 sts = my_find_image_symbol(&(thislib.name),&symdsc,
317 &entry,&(thislib.defspec));
318 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tlib$find_image_symbol returns %d\n",sts));
319 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "\tentry point is %d\n",
320 (unsigned long int) entry));
323 ST(0) = &PL_sv_undef;
325 else ST(0) = sv_2mortal(newSViv(PTR2IV(entry)));
333 # These functions should not need changing on any platform:
336 dl_install_xsub(perl_name, symref, filename="$Package")
339 const char * filename
341 DLDEBUG(2,PerlIO_printf(Perl_debug_log, "dl_install_xsub(name=%s, symref=%x)\n",
343 ST(0) = sv_2mortal(newRV((SV*)newXS_flags(perl_name,
344 (void(*)(pTHX_ CV *))symref,
346 XS_DYNAMIC_FILENAME)));
353 RETVAL = dl_last_error ;
357 #if defined(USE_ITHREADS)
364 /* MY_CXT_CLONE just does a memcpy on the whole structure, so to avoid
365 * using Perl variables that belong to another thread, we create our
366 * own for this thread.
368 MY_CXT.x_dl_last_error = newSVpvn("", 0);
369 dl_require_symbols = get_av("DynaLoader::dl_require_symbols", GV_ADDMULTI);