dl_aix.xs

UNIX下perl实现代码

	if (--mp->refCnt > 0)
		return 0;
	result = UNLOAD(mp->entry);
	if (result == -1) {
		errvalid++;
		strerrorcpy(errbuf, errno);
	}
	if (mp->exports) {
		register ExportPtr ep;
		register int i;
		for (ep = mp->exports, i = mp->nExports; i; i--, ep++)
			if (ep->name)
				safefree(ep->name);
		safefree(mp->exports);
	}
	if (mp == modList)
		modList = mp->next;
	else {
		for (mp1 = modList; mp1; mp1 = mp1->next)
			if (mp1->next == mp) {
				mp1->next = mp->next;
				break;
			}
	}
	safefree(mp->name);
	safefree(mp);
	return result;
}

/* Added by Wayne Scott 
 * This is needed because the ldopen system call calls
 * calloc to allocated a block of date.  The ldclose call calls free.
 * Without this we get this system calloc and perl's free, resulting
 * in a "Bad free" message.  This way we always use perl's malloc.
 */
void *calloc(size_t ne, size_t sz) 
{
  void *out;

  out = (void *) safemalloc(ne*sz);
  memzero(out, ne*sz);
  return(out);
}
 
/*
 * Build the export table from the XCOFF .loader section.
 */
static int readExports(ModulePtr mp)
{
	dTHX;
	LDFILE *ldp = NULL;
	AIX_SCNHDR sh;
	AIX_LDHDR *lhp;
	char *ldbuf;
	AIX_LDSYM *ls;
	int i;
	ExportPtr ep;

	if ((ldp = ldopen(mp->name, ldp)) == NULL) {
		struct ld_info *lp;
		char *buf;
		int size = 4*1024;
		if (errno != ENOENT) {
			errvalid++;
			strcpy(errbuf, "readExports: ");
			strerrorcat(errbuf, errno);
			return -1;
		}
		/*
		 * The module might be loaded due to the LIBPATH
		 * environment variable. Search for the loaded
		 * module using L_GETINFO.
		 */
		if ((buf = safemalloc(size)) == NULL) {
			errvalid++;
			strcpy(errbuf, "readExports: ");
			strerrorcat(errbuf, errno);
			return -1;
		}
		while ((i = loadquery(L_GETINFO, buf, size)) == -1 && errno == ENOMEM) {
			safefree(buf);
			size += 4*1024;
			if ((buf = safemalloc(size)) == NULL) {
				errvalid++;
				strcpy(errbuf, "readExports: ");
				strerrorcat(errbuf, errno);
				return -1;
			}
		}
		if (i == -1) {
			errvalid++;
			strcpy(errbuf, "readExports: ");
			strerrorcat(errbuf, errno);
			safefree(buf);
			return -1;
		}
		/*
		 * Traverse the list of loaded modules. The entry point
		 * returned by LOAD() does actually point to the data
		 * segment origin.
		 */
		lp = (struct ld_info *)buf;
		while (lp) {
			if (lp->ldinfo_dataorg == mp->entry) {
				ldp = ldopen(lp->ldinfo_filename, ldp);
				break;
			}
			if (lp->ldinfo_next == 0)
				lp = NULL;
			else
				lp = (struct ld_info *)((char *)lp + lp->ldinfo_next);
		}
		safefree(buf);
		if (!ldp) {
			errvalid++;
			strcpy(errbuf, "readExports: ");
			strerrorcat(errbuf, errno);
			return -1;
		}
	}
#ifdef USE_64_BIT_ALL
	if (TYPE(ldp) != U803XTOCMAGIC) {
#else
	if (TYPE(ldp) != U802TOCMAGIC) {
#endif
		errvalid++;
		strcpy(errbuf, "readExports: bad magic");
		while(ldclose(ldp) == FAILURE)
			;
		return -1;
	}
	if (ldnshread(ldp, _LOADER, &sh) != SUCCESS) {
		errvalid++;
		strcpy(errbuf, "readExports: cannot read loader section header");
		while(ldclose(ldp) == FAILURE)
			;
		return -1;
	}
	/*
	 * We read the complete loader section in one chunk, this makes
	 * finding long symbol names residing in the string table easier.
	 */
	if ((ldbuf = (char *)safemalloc(sh.s_size)) == NULL) {
		errvalid++;
		strcpy(errbuf, "readExports: ");
		strerrorcat(errbuf, errno);
		while(ldclose(ldp) == FAILURE)
			;
		return -1;
	}
	if (FSEEK(ldp, sh.s_scnptr, BEGINNING) != OKFSEEK) {
		errvalid++;
		strcpy(errbuf, "readExports: cannot seek to loader section");
		safefree(ldbuf);
		while(ldclose(ldp) == FAILURE)
			;
		return -1;
	}
/* This first case is a hack, since it assumes that the 3rd parameter to
   FREAD is 1. See the redefinition of FREAD above to see how this works. */
	if (FREAD(ldbuf, sh.s_size, 1, ldp) != 1) {
		errvalid++;
		strcpy(errbuf, "readExports: cannot read loader section");
		safefree(ldbuf);
		while(ldclose(ldp) == FAILURE)
			;
		return -1;
	}
	lhp = (AIX_LDHDR *)ldbuf;
	ls = (AIX_LDSYM *)(ldbuf+AIX_LDHDRSZ);
	/*
	 * Count the number of exports to include in our export table.
	 */
	for (i = lhp->l_nsyms; i; i--, ls++) {
		if (!LDR_EXPORT(*ls))
			continue;
		mp->nExports++;
	}
	Newz(1001, mp->exports, mp->nExports, Export);
	if (mp->exports == NULL) {
		errvalid++;
		strcpy(errbuf, "readExports: ");
		strerrorcat(errbuf, errno);
		safefree(ldbuf);
		while(ldclose(ldp) == FAILURE)
			;
		return -1;
	}
	/*
	 * Fill in the export table. All entries are relative to
	 * the entry point we got from load.
	 */
	ep = mp->exports;
	ls = (AIX_LDSYM *)(ldbuf+AIX_LDHDRSZ);
	for (i = lhp->l_nsyms; i; i--, ls++) {
		char *symname;
		if (!LDR_EXPORT(*ls))
			continue;
#ifndef USE_64_BIT_ALL
		if (ls->l_zeroes == 0)
#endif
			symname = ls->l_offset+lhp->l_stoff+ldbuf;
#ifndef USE_64_BIT_ALL
		else
			symname = ls->l_name;
#endif
		ep->name = savepv(symname);
		ep->addr = (void *)((unsigned long)mp->entry + ls->l_value);
		ep++;
	}
	safefree(ldbuf);
	while(ldclose(ldp) == FAILURE)
		;
	return 0;
}

/*
 * Find the main modules entry point. This is used as export pointer
 * for loadbind() to be able to resolve references to the main part.
 */
static void * findMain(void)
{
	struct ld_info *lp;
	char *buf;
	int size = 4*1024;
	int i;
	void *ret;

	if ((buf = safemalloc(size)) == NULL) {
		errvalid++;
		strcpy(errbuf, "findMain: ");
		strerrorcat(errbuf, errno);
		return NULL;
	}
	while ((i = loadquery(L_GETINFO, buf, size)) == -1 && errno == ENOMEM) {
		safefree(buf);
		size += 4*1024;
		if ((buf = safemalloc(size)) == NULL) {
			errvalid++;
			strcpy(errbuf, "findMain: ");
			strerrorcat(errbuf, errno);
			return NULL;
		}
	}
	if (i == -1) {
		errvalid++;
		strcpy(errbuf, "findMain: ");
		strerrorcat(errbuf, errno);
		safefree(buf);
		return NULL;
	}
	/*
	 * The first entry is the main module. The entry point
	 * returned by load() does actually point to the data
	 * segment origin.
	 */
	lp = (struct ld_info *)buf;
	ret = lp->ldinfo_dataorg;
	safefree(buf);
	return ret;
}

/* dl_dlopen.xs
 * 
 * Platform:	SunOS/Solaris, possibly others which use dlopen.
 * Author:	Paul Marquess ([e-mail])
 * Created:	10th July 1994
 *
 * Modified:
 * 15th July 1994   - Added code to explicitly save any error messages.
 * 3rd August 1994  - Upgraded to v3 spec.
 * 9th August 1994  - Changed to use IV
 * 10th August 1994 - Tim Bunce: Added RTLD_LAZY, switchable debugging,
 *                    basic FreeBSD support, removed ClearError
 *
 */

/* Porting notes:

	see dl_dlopen.xs

*/

#include "dlutils.c"	/* SaveError() etc	*/


static void
dl_private_init(pTHX)
{
    (void)dl_generic_private_init(aTHX);
}
 
MODULE = DynaLoader     PACKAGE = DynaLoader

BOOT:
    (void)dl_private_init(aTHX);


void *
dl_load_file(filename, flags=0)
	char *	filename
	int	flags
	CODE:
	DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_load_file(%s,%x):\n", filename,flags));
	if (flags & 0x01)
	    Perl_warn(aTHX_ "Can't make loaded symbols global on this platform while loading %s",filename);
	RETVAL = dlopen(filename, 1) ;
	DLDEBUG(2,PerlIO_printf(Perl_debug_log, " libref=%x\n", RETVAL));
	ST(0) = sv_newmortal() ;
	if (RETVAL == NULL)
	    SaveError(aTHX_ "%s",dlerror()) ;
	else
	    sv_setiv( ST(0), PTR2IV(RETVAL) );

int
dl_unload_file(libref)
    void *	libref
  CODE:
    DLDEBUG(1,PerlIO_printf(Perl_debug_log, "dl_unload_file(%lx):\n", libref));
    RETVAL = (dlclose(libref) == 0 ? 1 : 0);
    if (!RETVAL)
        SaveError(aTHX_ "%s", dlerror()) ;
    DLDEBUG(2,PerlIO_printf(Perl_debug_log, " retval = %d\n", RETVAL));
  OUTPUT:
    RETVAL

void *
dl_find_symbol(libhandle, symbolname)
	void *		libhandle
	char *		symbolname
	CODE:
	DLDEBUG(2,PerlIO_printf(Perl_debug_log, "dl_find_symbol(handle=%x, symbol=%s)\n",
		libhandle, symbolname));
	RETVAL = dlsym(libhandle, symbolname);
	DLDEBUG(2,PerlIO_printf(Perl_debug_log, "  symbolref = %x\n", RETVAL));
	ST(0) = sv_newmortal() ;
	if (RETVAL == NULL)
	    SaveError(aTHX_ "%s",dlerror()) ;
	else
	    sv_setiv( ST(0), PTR2IV(RETVAL));


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:
    RETVAL = LastError ;
    OUTPUT:
    RETVAL

# end.