Retrieve the flag bit that only 'p' uses, so that it is spare for

future use.

p4raw-id: //depot/perl@23892

diff --git a/genpacksizetables.pl b/genpacksizetables.pl
index b3e3a8c..2987499 100755 (executable)
--- a/genpacksizetables.pl
+++ b/genpacksizetables.pl
@@ -7,10 +7,10 @@ use Encode;
 my @lines = grep {!/^#/} <DATA>;
 
 sub addline {
-  my ($arrays, $chrmap, $letter, $arrayname, $noone, $nocsum, $size,
+  my ($arrays, $chrmap, $letter, $arrayname, $spare, $nocsum, $size,
       $condition) = @_;
   my $line = "/* $letter */ $size";
-  $line .= " | PACK_SIZE_CANNOT_ONLY_ONE" if $noone;
+  $line .= " | PACK_SIZE_SPARE" if $spare;
   $line .= " | PACK_SIZE_CANNOT_CSUM" if $nocsum;
   $line .= ",";
   # And then the hack
@@ -24,7 +24,7 @@ sub output_tables {
 
   my $chrmap = shift;
   foreach (@_) {
-    my ($letter, $shriek, $noone, $nocsum, $size, $condition)
+    my ($letter, $shriek, $spare, $nocsum, $size, $condition)
       = /^([A-Za-z])(!?)\t(\S*)\t(\S*)\t([^\t\n]+)(?:\t+(.*))?$/;
     die "Can't parse '$_'" unless $size;
 
@@ -36,7 +36,7 @@ sub output_tables {
     }
 
     addline (\%arrays, $chrmap, $letter, $shriek ? 'shrieking' : 'normal',
-            $noone, $nocsum, $size, $condition);
+            $spare, $nocsum, $size, $condition);
   }
 
   my %earliest;
@@ -100,7 +100,7 @@ output_tables (\%ebcdicmap, @lines);
 print "#endif\n";
 
 __DATA__
-#Symbol        nooone  nocsum  size
+#Symbol        spare   nocsum  size
 c                      char
 C                      unsigned char
 U                      char
@@ -126,7 +126,7 @@ N                   =SIZE32
 V!                     =SIZE32 PERL_PACK_CAN_SHRIEKSIGN
 N!                     =SIZE32 PERL_PACK_CAN_SHRIEKSIGN
 L                      =SIZE32
-p      *       *       char *
+p              *       char *
 w              *       char
 q                      Quad_t  HAS_QUAD
 Q                      Uquad_t HAS_QUAD

diff --git a/pp_pack.c b/pp_pack.c
index 4136893..8f76d69 100644 (file)
--- a/pp_pack.c
+++ b/pp_pack.c
@@ -272,7 +272,7 @@ S_mul128(pTHX_ SV *sv, U8 m)
 #endif
 
 #define PACK_SIZE_CANNOT_CSUM          0x80
-#define PACK_SIZE_CANNOT_ONLY_ONE      0x40
+#define PACK_SIZE_SPARE                        0x40
 #define PACK_SIZE_MASK                 0x3F
 
 
@@ -329,7 +329,7 @@ unsigned char size_normal[53] = {
   0,
   /* n */ SIZE16,
   0,
-  /* p */ sizeof(char *) | PACK_SIZE_CANNOT_ONLY_ONE | PACK_SIZE_CANNOT_CSUM,
+  /* p */ sizeof(char *) | PACK_SIZE_CANNOT_CSUM,
 #if defined(HAS_QUAD)
   /* q */ sizeof(Quad_t),
 #else
@@ -398,7 +398,7 @@ unsigned char size_normal[99] = {
   0,
   /* n */ SIZE16,
   0,
-  /* p */ sizeof(char *) | PACK_SIZE_CANNOT_ONLY_ONE | PACK_SIZE_CANNOT_CSUM,
+  /* p */ sizeof(char *) | PACK_SIZE_CANNOT_CSUM,
 #if defined(HAS_QUAD)
   /* q */ sizeof(Quad_t),
 #else
@@ -935,7 +935,8 @@ S_unpack_rec(pTHX_ register tempsym_t* symptr, register char *s, char *strbeg, c
        {
            int which = (symptr->code & TYPE_IS_SHRIEKING)
                ? PACK_SIZE_SHRIEKING : PACK_SIZE_NORMAL;
-           int offset = TYPE_NO_MODIFIERS(datumtype) - packsize[which].first;
+           const int rawtype = TYPE_NO_MODIFIERS(datumtype);
+           int offset = rawtype - packsize[which].first;
 
            if (offset >= 0 && offset < packsize[which].size) {
                /* Data about this template letter  */
@@ -948,9 +949,17 @@ S_unpack_rec(pTHX_ register tempsym_t* symptr, register char *s, char *strbeg, c
                    if (len > howmany)
                        len = howmany;
 
+                   /* In the old code, 'p' was the only type without shortcut
+                      code to curtail unpacking to only one.  As far as I can
+                      see the only point of retaining this anomaly is to make
+                      code such as $_ = unpack "p2", pack "pI", "Hi", 2
+                      continue to segfault. ie, it probably should be
+                      construed as a bug.
+                   */
+
                    if (!checksum || (data & PACK_SIZE_CANNOT_CSUM)) {
                        if (len && unpack_only_one &&
-                           !(data & PACK_SIZE_CANNOT_ONLY_ONE))
+                           rawtype != 'p')
                            len = 1;
                        EXTEND(SP, len);
                        EXTEND_MORTAL(len);