3 * Platform: OpenVMS, VAX or AXP
4 * Author: Charles Bailey bailey@genetics.upenn.edu
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$find_image_symbol would use if
38 * it were passed a given file specification. The file specification passed
39 * to dl_expandspec() and dl_load_file() can be partial or complete, and can
40 * use VMS or Unix syntax; these routines perform the necessary conversions.
41 * In general, writers of perl extensions need only conform to the
42 * procedures set out in the DynaLoader documentation, and let the details
43 * be taken care of by the routines here and in DynaLoader.pm. If anyone
44 * comes across any incompatibilities, please let me know. Thanks.
52 #include "dlutils.c" /* dl_debug, LastError; SaveError not used */
54 * dl_debug and LastError are static vars; you'll need to deal
55 * with them appropriately if you need context independence
60 #include <lib$routines.h>
65 typedef unsigned long int vmssts;
68 struct dsc$descriptor_s name;
69 struct dsc$descriptor_s defspec;
72 /* Static data for dl_expand_filespec() - This is static to save
73 * initialization on each call; if you need context-independence,
74 * just make these auto variables in dl_expandspec() and dl_load_file()
76 static char dlesa[NAM$C_MAXRSS], dlrsa[NAM$C_MAXRSS];
77 static struct FAB dlfab;
78 static struct NAM dlnam;
80 /* $PutMsg action routine - records error message in LastError */
82 copy_errmsg(msg,unused)
83 struct dsc$descriptor_s * msg;
86 if (*(msg->dsc$a_pointer) == '%') { /* first line */
88 strncpy((LastError = saferealloc(LastError,msg->dsc$w_length)),
89 msg->dsc$a_pointer, msg->dsc$w_length);
91 strncpy((LastError = safemalloc(msg->dsc$w_length)),
92 msg->dsc$a_pointer, msg->dsc$w_length);
95 else { /* continuation line */
96 int errlen = strlen(LastError);
97 LastError = saferealloc(LastError, errlen + msg->dsc$w_length + 1);
98 LastError[errlen] = '\n'; LastError[errlen+1] = '\0';
99 strncat(LastError, msg->dsc$a_pointer, msg->dsc$w_length);
103 /* Use $PutMsg to retrieve error message for failure status code */
105 dl_set_error(sts,stv)
111 vec[0] = stv ? 2 : 1;
112 vec[1] = sts; vec[2] = stv;
113 _ckvmssts(sys$putmsg(vec,copy_errmsg,0,0));
119 dl_generic_private_init();
120 /* Set up the static control blocks for dl_expand_filespec() */
123 dlfab.fab$l_nam = &dlnam;
124 dlnam.nam$l_esa = dlesa;
125 dlnam.nam$b_ess = sizeof dlesa;
126 dlnam.nam$l_rsa = dlrsa;
127 dlnam.nam$b_rss = sizeof dlrsa;
129 MODULE = DynaLoader PACKAGE = DynaLoader
132 (void)dl_private_init();
135 dl_expandspec(filespec)
138 char vmsspec[NAM$C_MAXRSS], defspec[NAM$C_MAXRSS];
142 tovmsspec(filespec,vmsspec);
143 dlfab.fab$l_fna = vmsspec;
144 dlfab.fab$b_fns = strlen(vmsspec);
147 DLDEBUG(1,fprintf(stderr,"dl_expand_filespec(%s):\n",vmsspec));
148 /* On the first pass, just parse the specification string */
149 dlnam.nam$b_nop = NAM$M_SYNCHK;
150 sts = sys$parse(&dlfab);
151 DLDEBUG(2,fprintf(stderr,"\tSYNCHK sys$parse = %d\n",sts));
153 dl_set_error(dlfab.fab$l_sts,dlfab.fab$l_stv);
157 /* Now set up a default spec - everything but the name */
158 deflen = dlnam.nam$l_name - dlesa;
159 memcpy(defspec,dlesa,deflen);
160 memcpy(defspec+deflen,dlnam.nam$l_type,
161 dlnam.nam$b_type + dlnam.nam$b_ver);
162 deflen += dlnam.nam$b_type + dlnam.nam$b_ver;
163 memcpy(vmsspec,dlnam.nam$l_name,dlnam.nam$b_name);
164 DLDEBUG(2,fprintf(stderr,"\tsplit filespec: name = %.*s, default = %.*s\n",
165 dlnam.nam$b_name,vmsspec,deflen,defspec));
166 /* . . . and go back to expand it */
168 dlfab.fab$l_dna = defspec;
169 dlfab.fab$b_dns = deflen;
170 dlfab.fab$b_fns = dlnam.nam$b_name;
171 sts = sys$parse(&dlfab);
172 DLDEBUG(2,fprintf(stderr,"\tname/default sys$parse = %d\n",sts));
174 dl_set_error(dlfab.fab$l_sts,dlfab.fab$l_stv);
178 /* Now find the actual file */
179 sts = sys$search(&dlfab);
180 DLDEBUG(2,fprintf(stderr,"\tsys$search = %d\n",sts));
181 if (!(sts & 1) && sts != RMS$_FNF) {
182 dl_set_error(dlfab.fab$l_sts,dlfab.fab$l_stv);
186 ST(0) = sv_2mortal(newSVpv(dlnam.nam$l_rsa,dlnam.nam$b_rsl));
187 DLDEBUG(1,fprintf(stderr,"\tresult = \\%.*s\\\n",
188 dlnam.nam$b_rsl,dlnam.nam$l_rsa));
194 dl_load_file(filespec)
197 char vmsspec[NAM$C_MAXRSS];
199 SV *reqSV, **reqSVhndl;
201 struct dsc$descriptor_s
202 specdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0},
203 symdsc = {0, DSC$K_DTYPE_T, DSC$K_CLASS_S, 0};
205 unsigned short int len;
206 unsigned short int code;
208 } namlst[2] = {{0,FSCN$_NAME,0},{0,0,0}};
209 struct libref *dlptr;
210 vmssts sts, failed = 0;
213 DLDEBUG(1,fprintf(stderr,"dl_load_file(%s):\n",filespec));
214 specdsc.dsc$a_pointer = tovmsspec(filespec,vmsspec);
215 specdsc.dsc$w_length = strlen(specdsc.dsc$a_pointer);
216 DLDEBUG(2,fprintf(stderr,"\tVMS-ified filespec is %s\n",
217 specdsc.dsc$a_pointer));
218 New(7901,dlptr,1,struct libref);
219 dlptr->name.dsc$b_dtype = dlptr->defspec.dsc$b_dtype = DSC$K_DTYPE_T;
220 dlptr->name.dsc$b_class = dlptr->defspec.dsc$b_class = DSC$K_CLASS_S;
221 sts = sys$filescan(&specdsc,namlst,0);
222 DLDEBUG(2,fprintf(stderr,"\tsys$filescan: returns %d, name is %.*s\n",
223 sts,namlst[0].len,namlst[0].string));
229 dlptr->name.dsc$w_length = namlst[0].len;
230 dlptr->name.dsc$a_pointer = savepvn(namlst[0].string,namlst[0].len);
231 dlptr->defspec.dsc$w_length = specdsc.dsc$w_length - namlst[0].len;
232 dlptr->defspec.dsc$a_pointer = safemalloc(dlptr->defspec.dsc$w_length + 1);
233 deflen = namlst[0].string - specdsc.dsc$a_pointer;
234 memcpy(dlptr->defspec.dsc$a_pointer,specdsc.dsc$a_pointer,deflen);
235 memcpy(dlptr->defspec.dsc$a_pointer + deflen,
236 namlst[0].string + namlst[0].len,
237 dlptr->defspec.dsc$w_length - deflen);
238 DLDEBUG(2,fprintf(stderr,"\tlibref = name: %s, defspec: %.*s\n",
239 dlptr->name.dsc$a_pointer,
240 dlptr->defspec.dsc$w_length,
241 dlptr->defspec.dsc$a_pointer));
242 if (!(reqAV = GvAV(gv_fetchpv("DynaLoader::dl_require_symbols",
244 || !(reqSVhndl = av_fetch(reqAV,0,FALSE)) || !(reqSV = *reqSVhndl)) {
245 DLDEBUG(2,fprintf(stderr,"\t@dl_require_symbols empty, returning untested libref\n"));
248 symdsc.dsc$w_length = SvCUR(reqSV);
249 symdsc.dsc$a_pointer = SvPVX(reqSV);
250 DLDEBUG(2,fprintf(stderr,"\t$dl_require_symbols[0] = %.*s\n",
251 symdsc.dsc$w_length, symdsc.dsc$a_pointer));
252 sts = lib$find_image_symbol(&(dlptr->name),&symdsc,
253 &entry,&(dlptr->defspec));
254 DLDEBUG(2,fprintf(stderr,"\tlib$find_image_symbol returns %d\n",sts));
263 Safefree(dlptr->name.dsc$a_pointer);
264 Safefree(dlptr->defspec.dsc$a_pointer);
269 ST(0) = sv_2mortal(newSViv((IV) dlptr));
274 dl_find_symbol(librefptr,symname)
278 struct libref thislib = *((struct libref *)librefptr);
279 struct dsc$descriptor_s
280 symdsc = {SvCUR(symname),DSC$K_DTYPE_T,DSC$K_CLASS_S,SvPVX(symname)};
284 DLDEBUG(1,fprintf(stderr,"dl_find_dymbol(%.*s,%.*s):\n",
285 thislib.name.dsc$w_length, thislib.name.dsc$a_pointer,
286 symdsc.dsc$w_length,symdsc.dsc$a_pointer));
287 sts = lib$find_image_symbol(&(thislib.name),&symdsc,
288 &entry,&(thislib.defspec));
289 DLDEBUG(2,fprintf(stderr,"\tlib$find_image_symbol returns %d\n",sts));
290 DLDEBUG(2,fprintf(stderr,"\tentry point is %d\n",
291 (unsigned long int) entry));
296 else ST(0) = sv_2mortal(newSViv((IV) entry));
304 # These functions should not need changing on any platform:
307 dl_install_xsub(perl_name, symref, filename="$Package")
312 DLDEBUG(2,fprintf(stderr,"dl_install_xsub(name=%s, symref=%x)\n",
314 ST(0)=sv_2mortal(newRV((SV*)newXS(perl_name, (void(*)())symref, filename)));