--- JSON-XS/XS.xs	2007/07/01 22:20:00	1.48
+++ JSON-XS/XS.xs	2007/07/02 00:48:18	1.51
@@ -27,11 +27,12 @@
 #define F_ALLOW_NONREF   0x00000100UL
 #define F_SHRINK         0x00000200UL
 #define F_ALLOW_BLESSED  0x00000400UL
-#define F_CONV_BLESSED   0x00000800UL // NYI
+#define F_CONV_BLESSED   0x00000800UL
 #define F_MAXDEPTH       0xf8000000UL
 #define S_MAXDEPTH       27
 #define F_MAXSIZE        0x01f00000UL
 #define S_MAXSIZE        20
+#define F_HOOK           0x00080000UL // some hooks exist, so slow-path processing
 
 #define DEC_DEPTH(flags) (1UL << ((flags & F_MAXDEPTH) >> S_MAXDEPTH))
 #define DEC_SIZE(flags)  (1UL << ((flags & F_MAXSIZE ) >> S_MAXSIZE ))
@@ -63,6 +64,7 @@
 
 typedef struct {
   U32 flags;
+  SV *cb_object, *cb_sk_object;
 } JSON;
 
 /////////////////////////////////////////////////////////////////////////////
@@ -472,10 +474,10 @@
     {
       if (SvSTASH (sv) == json_boolean_stash)
         {
-          if (SvIV (sv) == 0)
-            encode_str (enc, "false", 5, 0);
-          else
+          if (SvIV (sv))
             encode_str (enc, "true", 4, 0);
+          else
+            encode_str (enc, "false", 5, 0);
         }
       else
         {
@@ -492,10 +494,7 @@
 
               if (to_json)
                 {
-                  dSP;
-                  ENTER;
-                  SAVETMPS;
-                  PUSHMARK (SP);
+                  dSP; ENTER; SAVETMPS; PUSHMARK (SP);
                   XPUSHs (sv_bless (sv_2mortal (newRV_inc (sv)), SvSTASH (sv)));
 
                   // calling with G_SCALAR ensures that we always get a 1 reutrn value
@@ -506,8 +505,7 @@
 
                   encode_sv (enc, POPs);
 
-                  FREETMPS;
-                  LEAVE;
+                  FREETMPS; LEAVE;
                 }
               else if (enc->json.flags & F_ALLOW_BLESSED)
                 encode_str (enc, "null", 4, 0);
@@ -528,10 +526,13 @@
     encode_av (enc, (AV *)sv);
   else if (svt < SVt_PVAV)
     {
-      if (SvNIOK (sv) && SvIV (sv) == 0)
-        encode_str (enc, "false", 5, 0);
-      else if (SvNIOK (sv) && SvIV (sv) == 1)
+      STRLEN len = 0;
+      char *pv = svt ? SvPV (sv, len) : 0;
+
+      if (len == 1 && *pv == '1')
         encode_str (enc, "true", 4, 0);
+      else if (len == 1 && *pv == '0')
+        encode_str (enc, "false", 5, 0);
       else
         croak ("cannot encode reference to scalar '%s' unless the scalar is 0 or 1",
                SvPV_nolen (sv_2mortal (newRV_inc (sv))));
@@ -1010,6 +1011,7 @@
 static SV *
 decode_hv (dec_t *dec)
 {
+  SV *sv;
   HV *hv = newHV ();
 
   DEC_INC_DEPTH;
@@ -1093,7 +1095,54 @@
       }
 
   DEC_DEC_DEPTH;
-  return newRV_noinc ((SV *)hv);
+  sv = newRV_noinc ((SV *)hv);
+
+  // check filter callbacks
+  if (dec->json.flags & F_HOOK)
+    {
+      ENTER; SAVETMPS;
+
+      if (dec->json.cb_sk_object && HvKEYS (hv) == 1)
+        {
+          int count;
+
+          dSP; PUSHMARK (SP);
+          XPUSHs (sv_2mortal (sv));
+
+          PUTBACK; count = call_sv (dec->json.cb_sk_object, G_ARRAY); SPAGAIN;
+
+          if (count == 1)
+            {
+              sv = newSVsv (POPs);
+              goto filter_ok;
+            }
+
+          SvREFCNT_inc (sv);
+        }
+
+      if (dec->json.cb_object)
+        {
+          int count;
+
+          dSP; ENTER; SAVETMPS; PUSHMARK (SP);
+          XPUSHs (sv_2mortal (sv));
+
+          PUTBACK; count = call_sv (dec->json.cb_object, G_ARRAY); SPAGAIN;
+
+          if (count == 1)
+            {
+              sv = newSVsv (POPs);
+              goto filter_ok;
+            }
+
+          SvREFCNT_inc (sv);
+        }
+
+filter_ok:
+      FREETMPS; LEAVE;
+    }
+
+  return sv;
 
 fail:
   SvREFCNT_dec (hv);
@@ -1189,6 +1238,9 @@
   dec.depth    = 0;
   dec.maxdepth = DEC_DEPTH (dec.json.flags);
 
+  if (dec.json.cb_object || dec.json.cb_sk_object)
+    dec.json.flags |= F_HOOK;
+
   *dec.end = 0; // this should basically be a nop, too, but make sure it's there
   sv = decode_sv (&dec);
 
@@ -1272,7 +1324,7 @@
 {
   	SV *pv = NEWSV (0, sizeof (JSON));
         SvPOK_only (pv);
-        Zero (SvPVX (pv), 1, sizeof (JSON));
+        Zero (SvPVX (pv), 1, JSON);
         ((JSON *)SvPVX (pv))->flags = F_DEFAULT;
         XPUSHs (sv_2mortal (sv_bless (newRV_noinc (pv), json_stash)));
 }
@@ -1331,6 +1383,32 @@
 
         XPUSHs (ST (0));
 }
+
+void filter_json_object (JSON *self, SV *cb = &PL_sv_undef)
+	ALIAS:
+        filter_json_single_key_object = 1
+	PPCODE:
+{
+  	SV **svp;
+
+  	if (!SvOK (cb))
+          cb = 0;
+        else
+          cb = newSVsv (cb);
+
+        switch (ix)
+          {
+            case 0: svp = &self->cb_object   ; break;
+            case 1: svp = &self->cb_sk_object; break;
+          }
+
+        if (*svp)
+          SvREFCNT_dec (*svp);
+
+        *svp = cb;
+
+        XPUSHs (ST (0));
+}
 
 void encode (JSON *self, SV *scalar)
 	PPCODE: