This is a live mirror of the Perl 5 development currently hosted at https://github.com/perl/perl5
Small documentation fix to ExtUtils::Constant
[perl5.git] / util.c
diff --git a/util.c b/util.c
index 4a1a45f..52319d3 100644 (file)
--- a/util.c
+++ b/util.c
@@ -1,7 +1,7 @@
 /*    util.c
  *
  *    Copyright (C) 1993, 1994, 1995, 1996, 1997, 1998, 1999,
- *    2000, 2001, 2002, 2003, by Larry Wall and others
+ *    2000, 2001, 2002, 2003, 2004, by Larry Wall and others
  *
  *    You may distribute under the terms of either the GNU General Public
  *    License or the Artistic License, as specified in the README file.
  * not content."  --Gandalf
  */
 
+/* This file contains assorted utility routines.
+ * Which is a polite way of saying any stuff that people couldn't think of
+ * a better place for. Amongst other things, it includes the warning and
+ * dieing stuff, plus wrappers for malloc code.
+ */
+
 #include "EXTERN.h"
 #define PERL_IN_UTIL_C
 #include "perl.h"
 
 #ifndef PERL_MICRO
-#if !defined(NSIG) || defined(M_UNIX) || defined(M_XENIX)
 #include <signal.h>
-#endif
-
 #ifndef SIG_ERR
 # define SIG_ERR ((Sighandler_t) -1)
 #endif
@@ -75,7 +78,9 @@ Perl_safesysmalloc(MEM_SIZE size)
     else if (PL_nomemok)
        return Nullch;
     else {
-       PerlIO_puts(Perl_error_log,PL_no_mem) FLUSH;
+       /* Can't use PerlIO to write as it allocates memory */
+       PerlLIO_write(PerlIO_fileno(Perl_error_log),
+                     PL_no_mem, strlen(PL_no_mem));
        my_exit(1);
        return Nullch;
     }
@@ -122,7 +127,9 @@ Perl_safesysrealloc(Malloc_t where,MEM_SIZE size)
     else if (PL_nomemok)
        return Nullch;
     else {
-       PerlIO_puts(Perl_error_log,PL_no_mem) FLUSH;
+       /* Can't use PerlIO to write as it allocates memory */
+       PerlLIO_write(PerlIO_fileno(Perl_error_log),
+                     PL_no_mem, strlen(PL_no_mem));
        my_exit(1);
        return Nullch;
     }
@@ -174,7 +181,9 @@ Perl_safesyscalloc(MEM_SIZE count, MEM_SIZE size)
     else if (PL_nomemok)
        return Nullch;
     else {
-       PerlIO_puts(Perl_error_log,PL_no_mem) FLUSH;
+       /* Can't use PerlIO to write as it allocates memory */
+       PerlLIO_write(PerlIO_fileno(Perl_error_log),
+                     PL_no_mem, strlen(PL_no_mem));
        my_exit(1);
        return Nullch;
     }
@@ -748,12 +757,12 @@ be freed with the C<Safefree()> function.
 char *
 Perl_savepv(pTHX_ const char *pv)
 {
-    register char *newaddr = Nullch;
-    if (pv) {
-       New(902,newaddr,strlen(pv)+1,char);
-       (void)strcpy(newaddr,pv);
-    }
-    return newaddr;
+    register char *newaddr;
+    if (!pv)
+       return Nullch;
+
+    New(902,newaddr,strlen(pv)+1,char);
+    return strcpy(newaddr,pv);
 }
 
 /* same thing but with a known length */
@@ -777,13 +786,13 @@ Perl_savepvn(pTHX_ const char *pv, register I32 len)
     New(903,newaddr,len+1,char);
     /* Give a meaning to NULL pointer mainly for the use in sv_magic() */
     if (pv) {
-       Copy(pv,newaddr,len,char);      /* might not be null terminated */
-       newaddr[len] = '\0';            /* is now */
+       /* might not be null terminated */
+       newaddr[len] = '\0';
+       return CopyD(pv,newaddr,len,char);
     }
     else {
-       Zero(newaddr,len+1,char);
+       return ZeroD(newaddr,len+1,char);
     }
-    return newaddr;
 }
 
 /*
@@ -797,12 +806,17 @@ which is shared between threads.
 char *
 Perl_savesharedpv(pTHX_ const char *pv)
 {
-    register char *newaddr = Nullch;
-    if (pv) {
-       newaddr = (char*)PerlMemShared_malloc(strlen(pv)+1);
-       (void)strcpy(newaddr,pv);
+    register char *newaddr;
+    if (!pv)
+       return Nullch;
+
+    newaddr = (char*)PerlMemShared_malloc(strlen(pv)+1);
+    if (!newaddr) {
+       PerlLIO_write(PerlIO_fileno(Perl_error_log),
+                     PL_no_mem, strlen(PL_no_mem));
+       my_exit(1);
     }
-    return newaddr;
+    return strcpy(newaddr,pv);
 }
 
 
@@ -1023,74 +1037,94 @@ Perl_write_to_stderr(pTHX_ const char* message, int msglen)
     }
 }
 
-OP *
-Perl_vdie(pTHX_ const char* pat, va_list *args)
+/* Common code used by vcroak, vdie and vwarner  */
+
+void S_vdie_common(pTHX_ const char *message, STRLEN msglen, I32 utf8);
+
+char *
+S_vdie_croak_common(pTHX_ const char* pat, va_list* args, STRLEN* msglen,
+                   I32* utf8)
 {
     char *message;
-    int was_in_eval = PL_in_eval;
-    HV *stash;
-    GV *gv;
-    CV *cv;
-    SV *msv;
-    STRLEN msglen;
-    I32 utf8 = 0;
-
-    DEBUG_S(PerlIO_printf(Perl_debug_log,
-                         "%p: die: curstack = %p, mainstack = %p\n",
-                         thr, PL_curstack, PL_mainstack));
 
     if (pat) {
-       msv = vmess(pat, args);
+       SV *msv = vmess(pat, args);
        if (PL_errors && SvCUR(PL_errors)) {
            sv_catsv(PL_errors, msv);
-           message = SvPV(PL_errors, msglen);
+           message = SvPV(PL_errors, *msglen);
            SvCUR_set(PL_errors, 0);
        }
        else
-           message = SvPV(msv,msglen);
-       utf8 = SvUTF8(msv);
+           message = SvPV(msv,*msglen);
+       *utf8 = SvUTF8(msv);
     }
     else {
        message = Nullch;
-       msglen = 0;
     }
 
     DEBUG_S(PerlIO_printf(Perl_debug_log,
-                         "%p: die: message = %s\ndiehook = %p\n",
+                         "%p: die/croak: message = %s\ndiehook = %p\n",
                          thr, message, PL_diehook));
     if (PL_diehook) {
-       /* sv_2cv might call Perl_croak() */
-       SV *olddiehook = PL_diehook;
-       ENTER;
-       SAVESPTR(PL_diehook);
-       PL_diehook = Nullsv;
-       cv = sv_2cv(olddiehook, &stash, &gv, 0);
-       LEAVE;
-       if (cv && !CvDEPTH(cv) && (CvROOT(cv) || CvXSUB(cv))) {
-           dSP;
-           SV *msg;
+       S_vdie_common(aTHX_ message, *msglen, *utf8);
+    }
+    return message;
+}
 
-           ENTER;
-           save_re_context();
-           if (message) {
-               msg = newSVpvn(message, msglen);
-               SvFLAGS(msg) |= utf8;
-               SvREADONLY_on(msg);
-               SAVEFREESV(msg);
-           }
-           else {
-               msg = ERRSV;
-           }
+void
+S_vdie_common(pTHX_ const char *message, STRLEN msglen, I32 utf8)
+{
+    HV *stash;
+    GV *gv;
+    CV *cv;
+    /* sv_2cv might call Perl_croak() */
+    SV *olddiehook = PL_diehook;
+
+    assert(PL_diehook);
+    ENTER;
+    SAVESPTR(PL_diehook);
+    PL_diehook = Nullsv;
+    cv = sv_2cv(olddiehook, &stash, &gv, 0);
+    LEAVE;
+    if (cv && !CvDEPTH(cv) && (CvROOT(cv) || CvXSUB(cv))) {
+       dSP;
+       SV *msg;
 
-           PUSHSTACKi(PERLSI_DIEHOOK);
-           PUSHMARK(SP);
-           XPUSHs(msg);
-           PUTBACK;
-           call_sv((SV*)cv, G_DISCARD);
-           POPSTACK;
-           LEAVE;
+       ENTER;
+       save_re_context();
+       if (message) {
+           msg = newSVpvn(message, msglen);
+           SvFLAGS(msg) |= utf8;
+           SvREADONLY_on(msg);
+           SAVEFREESV(msg);
+       }
+       else {
+           msg = ERRSV;
        }
+
+       PUSHSTACKi(PERLSI_DIEHOOK);
+       PUSHMARK(SP);
+       XPUSHs(msg);
+       PUTBACK;
+       call_sv((SV*)cv, G_DISCARD);
+       POPSTACK;
+       LEAVE;
     }
+}
+
+OP *
+Perl_vdie(pTHX_ const char* pat, va_list *args)
+{
+    char *message;
+    int was_in_eval = PL_in_eval;
+    STRLEN msglen;
+    I32 utf8 = 0;
+
+    DEBUG_S(PerlIO_printf(Perl_debug_log,
+                         "%p: die: curstack = %p, mainstack = %p\n",
+                         thr, PL_curstack, PL_mainstack));
+
+    message = S_vdie_croak_common(aTHX_ pat, args, &msglen, &utf8);
 
     PL_restartop = die_where(message, msglen);
     SvFLAGS(ERRSV) |= utf8;
@@ -1131,65 +1165,11 @@ void
 Perl_vcroak(pTHX_ const char* pat, va_list *args)
 {
     char *message;
-    HV *stash;
-    GV *gv;
-    CV *cv;
-    SV *msv;
     STRLEN msglen;
     I32 utf8 = 0;
 
-    if (pat) {
-       msv = vmess(pat, args);
-       if (PL_errors && SvCUR(PL_errors)) {
-           sv_catsv(PL_errors, msv);
-           message = SvPV(PL_errors, msglen);
-           SvCUR_set(PL_errors, 0);
-       }
-       else
-           message = SvPV(msv,msglen);
-       utf8 = SvUTF8(msv);
-    }
-    else {
-       message = Nullch;
-       msglen = 0;
-    }
-
-    DEBUG_S(PerlIO_printf(Perl_debug_log, "croak: 0x%"UVxf" %s",
-                         PTR2UV(thr), message));
-
-    if (PL_diehook) {
-       /* sv_2cv might call Perl_croak() */
-       SV *olddiehook = PL_diehook;
-       ENTER;
-       SAVESPTR(PL_diehook);
-       PL_diehook = Nullsv;
-       cv = sv_2cv(olddiehook, &stash, &gv, 0);
-       LEAVE;
-       if (cv && !CvDEPTH(cv) && (CvROOT(cv) || CvXSUB(cv))) {
-           dSP;
-           SV *msg;
+    message = S_vdie_croak_common(aTHX_ pat, args, &msglen, &utf8);
 
-           ENTER;
-           save_re_context();
-           if (message) {
-               msg = newSVpvn(message, msglen);
-               SvFLAGS(msg) |= utf8;
-               SvREADONLY_on(msg);
-               SAVEFREESV(msg);
-           }
-           else {
-               msg = ERRSV;
-           }
-
-           PUSHSTACKi(PERLSI_DIEHOOK);
-           PUSHMARK(SP);
-           XPUSHs(msg);
-           PUTBACK;
-           call_sv((SV*)cv, G_DISCARD);
-           POPSTACK;
-           LEAVE;
-       }
-    }
     if (PL_in_eval) {
        PL_restartop = die_where(message, msglen);
        SvFLAGS(ERRSV) |= utf8;
@@ -1221,8 +1201,9 @@ Perl_croak_nocontext(const char *pat, ...)
 =for apidoc croak
 
 This is the XSUB-writer's interface to Perl's C<die> function.
-Normally use this function the same way you use the C C<printf>
-function.  See C<warn>.
+Normally call this function the same way you call the C C<printf>
+function.  Calling C<croak> returns control directly to Perl,
+sidestepping the normal C order of execution. See C<warn>.
 
 If you want to throw an exception object, assign the object to
 C<$@> and then pass C<Nullch> to croak():
@@ -1307,9 +1288,8 @@ Perl_warn_nocontext(const char *pat, ...)
 /*
 =for apidoc warn
 
-This is the XSUB-writer's interface to Perl's C<warn> function.  Use this
-function the same way you use the C C<printf> function.  See
-C<croak>.
+This is the XSUB-writer's interface to Perl's C<warn> function.  Call this
+function the same way you call the C C<printf> function.  See C<croak>.
 
 =cut
 */
@@ -1347,46 +1327,15 @@ Perl_warner(pTHX_ U32  err, const char* pat,...)
 void
 Perl_vwarner(pTHX_ U32  err, const char* pat, va_list* args)
 {
-    char *message;
-    HV *stash;
-    GV *gv;
-    CV *cv;
-    SV *msv;
-    STRLEN msglen;
-    I32 utf8 = 0;
-
-    msv = vmess(pat, args);
-    message = SvPV(msv, msglen);
-    utf8 = SvUTF8(msv);
-
     if (ckDEAD(err)) {
+       SV *msv = vmess(pat, args);
+       STRLEN msglen;
+       char *message = SvPV(msv, msglen);
+       I32 utf8 = SvUTF8(msv);
+
        if (PL_diehook) {
-           /* sv_2cv might call Perl_croak() */
-           SV *olddiehook = PL_diehook;
-           ENTER;
-           SAVESPTR(PL_diehook);
-           PL_diehook = Nullsv;
-           cv = sv_2cv(olddiehook, &stash, &gv, 0);
-           LEAVE;
-           if (cv && !CvDEPTH(cv) && (CvROOT(cv) || CvXSUB(cv))) {
-               dSP;
-               SV *msg;
-
-               ENTER;
-               save_re_context();
-               msg = newSVpvn(message, msglen);
-               SvFLAGS(msg) |= utf8;
-               SvREADONLY_on(msg);
-               SAVEFREESV(msg);
-
-               PUSHSTACKi(PERLSI_DIEHOOK);
-               PUSHMARK(sp);
-               XPUSHs(msg);
-               PUTBACK;
-               call_sv((SV*)cv, G_DISCARD);
-               POPSTACK;
-               LEAVE;
-           }
+           assert(message);
+           S_vdie_common(aTHX_ message, msglen, utf8);
        }
        if (PL_in_eval) {
            PL_restartop = die_where(message, msglen);
@@ -1397,36 +1346,7 @@ Perl_vwarner(pTHX_ U32  err, const char* pat, va_list* args)
        my_failure_exit();
     }
     else {
-       if (PL_warnhook) {
-           /* sv_2cv might call Perl_warn() */
-           SV *oldwarnhook = PL_warnhook;
-           ENTER;
-           SAVESPTR(PL_warnhook);
-           PL_warnhook = Nullsv;
-           cv = sv_2cv(oldwarnhook, &stash, &gv, 0);
-           LEAVE;
-           if (cv && !CvDEPTH(cv) && (CvROOT(cv) || CvXSUB(cv))) {
-               dSP;
-               SV *msg;
-
-               ENTER;
-               save_re_context();
-               msg = newSVpvn(message, msglen);
-               SvFLAGS(msg) |= utf8;
-               SvREADONLY_on(msg);
-               SAVEFREESV(msg);
-
-               PUSHSTACKi(PERLSI_WARNHOOK);
-               PUSHMARK(sp);
-               XPUSHs(msg);
-               PUTBACK;
-               call_sv((SV*)cv, G_DISCARD);
-               POPSTACK;
-               LEAVE;
-               return;
-           }
-       }
-       write_to_stderr(message, msglen);
+       Perl_vwarn(aTHX_ pat, args);
     }
 }
 
@@ -1743,7 +1663,7 @@ Perl_my_ntohl(pTHX_ long l)
  * -DWS
  */
 
-#define HTOV(name,type)                                                \
+#define HTOLE(name,type)                                       \
        type                                                    \
        name (register type n)                                  \
        {                                                       \
@@ -1752,14 +1672,14 @@ Perl_my_ntohl(pTHX_ long l)
                char c[sizeof(type)];                           \
            } u;                                                \
            register I32 i;                                     \
-           register I32 s;                                     \
-           for (i = 0, s = 0; i < sizeof(u.c); i++, s += 8) {  \
+           register I32 s = 0;                                 \
+           for (i = 0; i < sizeof(u.c); i++, s += 8) {         \
                u.c[i] = (n >> s) & 0xFF;                       \
            }                                                   \
            return u.value;                                     \
        }
 
-#define VTOH(name,type)                                                \
+#define LETOH(name,type)                                       \
        type                                                    \
        name (register type n)                                  \
        {                                                       \
@@ -1768,27 +1688,218 @@ Perl_my_ntohl(pTHX_ long l)
                char c[sizeof(type)];                           \
            } u;                                                \
            register I32 i;                                     \
-           register I32 s;                                     \
+           register I32 s = 0;                                 \
            u.value = n;                                        \
            n = 0;                                              \
-           for (i = 0, s = 0; i < sizeof(u.c); i++, s += 8) {  \
-               n += (u.c[i] & 0xFF) << s;                      \
+           for (i = 0; i < sizeof(u.c); i++, s += 8) {         \
+               n |= ((type)(u.c[i] & 0xFF)) << s;              \
            }                                                   \
            return n;                                           \
        }
 
+/*
+ * Big-endian byte order functions.
+ */
+
+#define HTOBE(name,type)                                       \
+       type                                                    \
+       name (register type n)                                  \
+       {                                                       \
+           union {                                             \
+               type value;                                     \
+               char c[sizeof(type)];                           \
+           } u;                                                \
+           register I32 i;                                     \
+           register I32 s = 8*(sizeof(u.c)-1);                 \
+           for (i = 0; i < sizeof(u.c); i++, s -= 8) {         \
+               u.c[i] = (n >> s) & 0xFF;                       \
+           }                                                   \
+           return u.value;                                     \
+       }
+
+#define BETOH(name,type)                                       \
+       type                                                    \
+       name (register type n)                                  \
+       {                                                       \
+           union {                                             \
+               type value;                                     \
+               char c[sizeof(type)];                           \
+           } u;                                                \
+           register I32 i;                                     \
+           register I32 s = 8*(sizeof(u.c)-1);                 \
+           u.value = n;                                        \
+           n = 0;                                              \
+           for (i = 0; i < sizeof(u.c); i++, s -= 8) {         \
+               n |= ((type)(u.c[i] & 0xFF)) << s;              \
+           }                                                   \
+           return n;                                           \
+       }
+
+/*
+ * If we just can't do it...
+ */
+
+#define NOT_AVAIL(name,type)                                    \
+        type                                                    \
+        name (register type n)                                  \
+        {                                                       \
+            Perl_croak_nocontext(#name "() not available");     \
+            return n; /* not reached */                         \
+        }
+
+
 #if defined(HAS_HTOVS) && !defined(htovs)
-HTOV(htovs,short)
+HTOLE(htovs,short)
 #endif
 #if defined(HAS_HTOVL) && !defined(htovl)
-HTOV(htovl,long)
+HTOLE(htovl,long)
 #endif
 #if defined(HAS_VTOHS) && !defined(vtohs)
-VTOH(vtohs,short)
+LETOH(vtohs,short)
 #endif
 #if defined(HAS_VTOHL) && !defined(vtohl)
-VTOH(vtohl,long)
+LETOH(vtohl,long)
+#endif
+
+#ifdef PERL_NEED_MY_HTOLE16
+# if U16SIZE == 2
+HTOLE(Perl_my_htole16,U16)
+# else
+NOT_AVAIL(Perl_my_htole16,U16)
+# endif
+#endif
+#ifdef PERL_NEED_MY_LETOH16
+# if U16SIZE == 2
+LETOH(Perl_my_letoh16,U16)
+# else
+NOT_AVAIL(Perl_my_letoh16,U16)
+# endif
+#endif
+#ifdef PERL_NEED_MY_HTOBE16
+# if U16SIZE == 2
+HTOBE(Perl_my_htobe16,U16)
+# else
+NOT_AVAIL(Perl_my_htobe16,U16)
+# endif
+#endif
+#ifdef PERL_NEED_MY_BETOH16
+# if U16SIZE == 2
+BETOH(Perl_my_betoh16,U16)
+# else
+NOT_AVAIL(Perl_my_betoh16,U16)
+# endif
+#endif
+
+#ifdef PERL_NEED_MY_HTOLE32
+# if U32SIZE == 4
+HTOLE(Perl_my_htole32,U32)
+# else
+NOT_AVAIL(Perl_my_htole32,U32)
+# endif
+#endif
+#ifdef PERL_NEED_MY_LETOH32
+# if U32SIZE == 4
+LETOH(Perl_my_letoh32,U32)
+# else
+NOT_AVAIL(Perl_my_letoh32,U32)
+# endif
+#endif
+#ifdef PERL_NEED_MY_HTOBE32
+# if U32SIZE == 4
+HTOBE(Perl_my_htobe32,U32)
+# else
+NOT_AVAIL(Perl_my_htobe32,U32)
+# endif
+#endif
+#ifdef PERL_NEED_MY_BETOH32
+# if U32SIZE == 4
+BETOH(Perl_my_betoh32,U32)
+# else
+NOT_AVAIL(Perl_my_betoh32,U32)
+# endif
+#endif
+
+#ifdef PERL_NEED_MY_HTOLE64
+# if U64SIZE == 8
+HTOLE(Perl_my_htole64,U64)
+# else
+NOT_AVAIL(Perl_my_htole64,U64)
+# endif
+#endif
+#ifdef PERL_NEED_MY_LETOH64
+# if U64SIZE == 8
+LETOH(Perl_my_letoh64,U64)
+# else
+NOT_AVAIL(Perl_my_letoh64,U64)
+# endif
+#endif
+#ifdef PERL_NEED_MY_HTOBE64
+# if U64SIZE == 8
+HTOBE(Perl_my_htobe64,U64)
+# else
+NOT_AVAIL(Perl_my_htobe64,U64)
+# endif
+#endif
+#ifdef PERL_NEED_MY_BETOH64
+# if U64SIZE == 8
+BETOH(Perl_my_betoh64,U64)
+# else
+NOT_AVAIL(Perl_my_betoh64,U64)
+# endif
+#endif
+
+#ifdef PERL_NEED_MY_HTOLES
+HTOLE(Perl_my_htoles,short)
+#endif
+#ifdef PERL_NEED_MY_LETOHS
+LETOH(Perl_my_letohs,short)
+#endif
+#ifdef PERL_NEED_MY_HTOBES
+HTOBE(Perl_my_htobes,short)
+#endif
+#ifdef PERL_NEED_MY_BETOHS
+BETOH(Perl_my_betohs,short)
+#endif
+
+#ifdef PERL_NEED_MY_HTOLEI
+HTOLE(Perl_my_htolei,int)
+#endif
+#ifdef PERL_NEED_MY_LETOHI
+LETOH(Perl_my_letohi,int)
+#endif
+#ifdef PERL_NEED_MY_HTOBEI
+HTOBE(Perl_my_htobei,int)
+#endif
+#ifdef PERL_NEED_MY_BETOHI
+BETOH(Perl_my_betohi,int)
+#endif
+
+#ifdef PERL_NEED_MY_HTOLEL
+HTOLE(Perl_my_htolel,long)
+#endif
+#ifdef PERL_NEED_MY_LETOHL
+LETOH(Perl_my_letohl,long)
+#endif
+#ifdef PERL_NEED_MY_HTOBEL
+HTOBE(Perl_my_htobel,long)
 #endif
+#ifdef PERL_NEED_MY_BETOHL
+BETOH(Perl_my_betohl,long)
+#endif
+
+void
+Perl_my_swabn(void *ptr, int n)
+{
+    register char *s = (char *)ptr;
+    register char *e = s + (n-1);
+    register char tc;
+
+    for (n /= 2; n > 0; s++, e--, n--) {
+      tc = *s;
+      *s = *e;
+      *e = tc;
+    }
+}
 
 PerlIO *
 Perl_my_popen_list(pTHX_ char *mode, int n, SV **args)
@@ -3660,19 +3771,21 @@ an RV.
 
 Function must be called with an already existing SV like
 
-    sv = NEWSV(92,0);
-    s = scan_version(s,sv);
+    sv = newSV(0);
+    s = scan_version(s,SV *sv, bool qv);
 
 Performs some preprocessing to the string to ensure that
 it has the correct characteristics of a version.  Flags the
 object if it contains an underscore (which denotes this
-is a beta version).
+is a alpha version).  The boolean qv denotes that the version
+should be interpreted as if it had multiple decimals, even if
+it doesn't.
 
 =cut
 */
 
 char *
-Perl_scan_version(pTHX_ char *s, SV *rv)
+Perl_scan_version(pTHX_ char *s, SV *rv, bool qv)
 {
     const char *start = s;
     char *pos = s;
@@ -3680,6 +3793,7 @@ Perl_scan_version(pTHX_ char *s, SV *rv)
     bool saw_under = 0;
     SV* sv = newSVrv(rv, "version"); /* create an SV and upgrade the RV */
     (void)sv_upgrade(sv, SVt_PVAV); /* needs to be an AV type */
+    AvREAL_on((AV*)sv);
 
     /* pre-scan the imput string to check for decimals */
     while ( *pos == '.' || *pos == '_' || isDIGIT(*pos) )
@@ -3700,7 +3814,10 @@ Perl_scan_version(pTHX_ char *s, SV *rv)
     }
     pos = s;
 
-    if (*pos == 'v') pos++;  /* get past 'v' */
+    if (*pos == 'v') {
+       pos++;  /* get past 'v' */
+       qv = 1; /* force quoted version processing */
+    }
     while (isDIGIT(*pos))
        pos++;
     if (!isALPHA(*pos)) {
@@ -3716,14 +3833,14 @@ Perl_scan_version(pTHX_ char *s, SV *rv)
                I32 mult = 1;
                I32 orev;
                if ( s < pos && s > start && *(s-1) == '_' ) {
-                       mult *= -1;     /* beta version */
+                       mult *= -1;     /* alpha version */
                }
                /* the following if() will only be true after the decimal
                 * point of a version originally created with a bare
                 * floating point number, i.e. not quoted in any way
                 */
-               if ( s > start+1 && saw_period == 1 && !saw_under ) {
-                   mult = 100;
+               if ( !qv && s > start+1 && saw_period == 1 ) {
+                   mult *= 100;
                    while ( s < end ) {
                        orev = rev;
                        rev += (*s - '0') * mult;
@@ -3755,12 +3872,25 @@ Perl_scan_version(pTHX_ char *s, SV *rv)
                break;
            }
            while ( isDIGIT(*pos) ) {
-               if ( !saw_under && saw_period == 1 && pos-s == 3 )
+               if ( saw_period == 1 && pos-s == 3 )
                    break;
                pos++;
            }
        }
     }
+    if ( qv ) { /* quoted versions always become full version objects */
+       I32 len = av_len((AV *)sv);
+       /* This for loop appears to trigger a compiler bug on OS X, as it
+          loops infinitely. Yes, len is negative. No, it makes no sense.
+          Compiler in question is:
+          gcc version 3.3 20030304 (Apple Computer, Inc. build 1640)
+          for ( len = 2 - len; len > 0; len-- )
+          av_push((AV *)sv, newSViv(0));
+       */
+       len = 2 - len;
+       while (len-- > 0)
+           av_push((AV *)sv, newSViv(0));
+    }
     return s;
 }
 
@@ -3781,24 +3911,35 @@ SV *
 Perl_new_version(pTHX_ SV *ver)
 {
     SV *rv = newSV(0);
-    char *version;
-    if ( SvNOK(ver) ) /* may get too much accuracy */ 
+    if ( sv_derived_from(ver,"version") ) /* can just copy directly */
     {
-       char tbuf[64];
-       sprintf(tbuf,"%.9"NVgf, SvNVX(ver));
-       version = savepv(tbuf);
+       I32 key;
+       AV *av = (AV *)SvRV(ver);
+       SV* sv = newSVrv(rv, "version"); /* create an SV and upgrade the RV */
+       (void)sv_upgrade(sv, SVt_PVAV); /* needs to be an AV type */
+       AvREAL_on((AV*)sv);
+       for ( key = 0; key <= av_len(av); key++ )
+       {
+           I32 rev = SvIV(*av_fetch(av, key, FALSE));
+           av_push((AV *)sv, newSViv(rev));
+       }
+       return rv;
     }
 #ifdef SvVOK
-    else if ( SvVOK(ver) ) { /* already a v-string */
+    if ( SvVOK(ver) ) { /* already a v-string */
+       char *version;
        MAGIC* mg = mg_find(ver,PERL_MAGIC_vstring);
        version = savepvn( (const char*)mg->mg_ptr,mg->mg_len );
+       sv_setpv(rv,version);
+       Safefree(version);
     }
+    else {
 #endif
-    else /* must be a string or something like a string */
-    {
-       version = (char *)SvPV(ver,PL_na);
+    sv_setsv(rv,ver); /* make a duplicate */
+#ifdef SvVOK
     }
-    version = scan_version(version,rv);
+#endif
+    upg_version(rv);
     return rv;
 }
 
@@ -3817,14 +3958,29 @@ Returns a pointer to the upgraded SV.
 SV *
 Perl_upg_version(pTHX_ SV *ver)
 {
-    char *version = savepvn(SvPVX(ver),SvCUR(ver));
+    char *version;
+    bool qv = 0;
+
+    if ( SvNOK(ver) ) /* may get too much accuracy */ 
+    {
+       char tbuf[64];
+       sprintf(tbuf,"%.9"NVgf, SvNVX(ver));
+       version = savepv(tbuf);
+    }
 #ifdef SvVOK
-    if ( SvVOK(ver) ) { /* already a v-string */
+    else if ( SvVOK(ver) ) { /* already a v-string */
        MAGIC* mg = mg_find(ver,PERL_MAGIC_vstring);
        version = savepvn( (const char*)mg->mg_ptr,mg->mg_len );
+       qv = 1;
     }
 #endif
-    version = scan_version(version,ver);
+    else /* must be a string or something like a string */
+    {
+       STRLEN n_a;
+       version = savepv(SvPV(ver,n_a));
+    }
+    (void)scan_version(version, ver, qv);
+    Safefree(version);
     return ver;
 }
 
@@ -3847,7 +4003,7 @@ SV *
 Perl_vnumify(pTHX_ SV *vs)
 {
     I32 i, len, digit;
-    SV *sv = NEWSV(92,0);
+    SV *sv = newSV(0);
     if ( SvROK(vs) )
        vs = SvRV(vs);
     len = av_len((AV *)vs);
@@ -3857,25 +4013,38 @@ Perl_vnumify(pTHX_ SV *vs)
        return sv;
     }
     digit = SvIVX(*av_fetch((AV *)vs, 0, 0));
-    Perl_sv_setpvf(aTHX_ sv,"%d.", PERL_ABS(digit));
-    for ( i = 1 ; i <= len ; i++ )
+    Perl_sv_setpvf(aTHX_ sv,"%d.", (int)PERL_ABS(digit));
+    for ( i = 1 ; i < len ; i++ )
     {
        digit = SvIVX(*av_fetch((AV *)vs, i, 0));
-       Perl_sv_catpvf(aTHX_ sv,"%03d", PERL_ABS(digit));
+       Perl_sv_catpvf(aTHX_ sv,"%03d", (int)PERL_ABS(digit));
+    }
+
+    if ( len > 0 )
+    {
+       digit = SvIVX(*av_fetch((AV *)vs, len, 0));
+       if ( (int)PERL_ABS(digit) != 0 || len == 1 )
+       {
+           if ( digit < 0 ) /* alpha version */
+               Perl_sv_catpv(aTHX_ sv,"_");
+           /* Don't display additional trailing zeros */
+           Perl_sv_catpvf(aTHX_ sv,"%03d", (int)PERL_ABS(digit));
+       }
     }
-    if ( len == 0 )
+    else /* len == 0 */
+    {
         Perl_sv_catpv(aTHX_ sv,"000");
-    sv_setnv(sv, SvNV(sv));
+    }
     return sv;
 }
 
 /*
-=for apidoc vstringify
+=for apidoc vnormal
 
 Accepts a version object and returns the normalized string
 representation.  Call like:
 
-    sv = vstringify(rv);
+    sv = vnormal(rv);
 
 NOTE: you can pass either the object directly or the SV
 contained within the RV.
@@ -3884,10 +4053,10 @@ contained within the RV.
 */
 
 SV *
-Perl_vstringify(pTHX_ SV *vs)
+Perl_vnormal(pTHX_ SV *vs)
 {
     I32 i, len, digit;
-    SV *sv = NEWSV(92,0);
+    SV *sv = newSV(0);
     if ( SvROK(vs) )
        vs = SvRV(vs);
     len = av_len((AV *)vs);
@@ -3906,12 +4075,42 @@ Perl_vstringify(pTHX_ SV *vs)
        else
            Perl_sv_catpvf(aTHX_ sv,".%"IVdf,(IV)digit);
     }
-    if ( len == 0 )
-        Perl_sv_catpv(aTHX_ sv,".0");
+    
+    if ( len <= 2 ) { /* short version, must be at least three */
+       for ( len = 2 - len; len != 0; len-- )
+           Perl_sv_catpv(aTHX_ sv,".0");
+    }
+
     return sv;
 } 
 
 /*
+=for apidoc vstringify
+
+In order to maintain maximum compatibility with earlier versions
+of Perl, this function will return either the floating point
+notation or the multiple dotted notation, depending on whether
+the original version contained 1 or more dots, respectively
+
+=cut
+*/
+
+SV *
+Perl_vstringify(pTHX_ SV *vs)
+{
+    I32 len, digit;
+    if ( SvROK(vs) )
+       vs = SvRV(vs);
+    len = av_len((AV *)vs);
+    digit = SvIVX(*av_fetch((AV *)vs, len, 0));
+    
+    if ( len < 2 || ( len == 2 && digit < 0 ) )
+       return vnumify(vs);
+    else
+       return vnormal(vs);
+}
+
+/*
 =for apidoc vcmp
 
 Version object aware cmp.  Both operands must already have been 
@@ -3937,23 +4136,36 @@ Perl_vcmp(pTHX_ SV *lsv, SV *rsv)
     {
        I32 left  = SvIV(*av_fetch((AV *)lsv,i,0));
        I32 right = SvIV(*av_fetch((AV *)rsv,i,0));
-       bool lbeta = left  < 0 ? 1 : 0;
-       bool rbeta = right < 0 ? 1 : 0;
-       left  = PERL_ABS(left);
-       right = PERL_ABS(right);
-       if ( left < right || (left == right && lbeta && !rbeta) )
+       bool lalpha = left  < 0 ? 1 : 0;
+       bool ralpha = right < 0 ? 1 : 0;
+       left  = abs(left);
+       right = abs(right);
+       if ( left < right || (left == right && lalpha && !ralpha) )
            retval = -1;
-       if ( left > right || (left == right && rbeta && !lbeta) )
+       if ( left > right || (left == right && ralpha && !lalpha) )
            retval = +1;
        i++;
     }
 
-    if ( l != r && retval == 0 ) /* possible match except for trailing 0 */
+    if ( l != r && retval == 0 ) /* possible match except for trailing 0's */
     {
-       if ( !( l < r && r-l == 1 && SvIV(*av_fetch((AV *)rsv,r,0)) == 0 ) &&
-            !( l-r == 1 && SvIV(*av_fetch((AV *)lsv,l,0)) == 0 ) )
+       if ( l < r )
        {
-           retval = l < r ? -1 : +1; /* not a match after all */
+           while ( i <= r && retval == 0 )
+           {
+               if ( SvIV(*av_fetch((AV *)rsv,i,0)) != 0 )
+                   retval = -1; /* not a match after all */
+               i++;
+           }
+       }
+       else
+       {
+           while ( i <= l && retval == 0 )
+           {
+               if ( SvIV(*av_fetch((AV *)lsv,i,0)) != 0 )
+                   retval = +1; /* not a match after all */
+               i++;
+           }
        }
     }
     return retval;