X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=chiark-tcl.git;a=blobdiff_plain;f=hbytes%2Fchop.c;h=bbc423322b5675b55a250573be2e54424be210a2;hp=5d89cd22c0f44969a3a043f9a8014f3e18be8784;hb=ca8b96bf81245f21fe3906c71dc2994bfc5e516f;hpb=503f816f2157f764c7c93c873047aad4ca63e10d

diff --git a/hbytes/chop.c b/hbytes/chop.c
index 5d89cd2..bbc4233 100644
--- a/hbytes/chop.c
+++ b/hbytes/chop.c
@@ -1,59 +1,106 @@
 /*
+ * hbytes - hex-stringrep efficient byteblocks for Tcl
+ * Copyright 2006-2012 Ian Jackson
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
  */
 
-#include <string.h>
 
-#include "hbytes.h"
+#include "chiark_tcl_hbytes.h"
 
-static int strs(Tcl_Interp *ip, int strc, Tcl_Obj *const *strv, int *l_r) {
-  int rc, l, i;
+static int strs1(Tcl_Interp *ip, int strc, Tcl_Obj *const *strv, int *l_r) {
+  int rc, l, i, pl;
 
   l= 0;
   for (i=1; i<strc; i++) {
-    rc= Tcl_ConvertToType(ip,strv[i],&hbytes_type);
+    rc= Tcl_ConvertToType(ip,strv[i],&cht_hbytes_type);
     if (rc) return rc;
-    l += HBYTES_LEN(HBYTES(strv[i]));
+    pl= cht_hb_len(OBJ_HBYTES(strv[i]));
+    assert(l < INT_MAX/2 && pl < INT_MAX/2);
+    l += pl;
   }
   *l_r= l;
   return TCL_OK;
 }
 
-int app_pre(ClientData cd, Tcl_Interp *ip, int begin,
-	    HBytes_Var v, int strc, Tcl_Obj *const *strv) {
-  int ol, rc, al, i, tl;
-
-  rc= strs(ip,strc,strv,&al);  if (rc) return rc;
-
-  ol= HBYTES_LEN(*v.hb);
-  v.hb->start= v.hb->end= Tcl_Realloc(v.hb->start, ol + al);
-
-  if (begin) v.hb->end += ol;
-  else memmove(v.hb->start + al, v.hb->start, ol);
+static void strs2(Byte *dest, int strc, Tcl_Obj *const *strv) {
+  int tl, i;
   
   for (i=1; i<strc; i++) {
-    tl= HBYTES_LEN(HBYTES(strv[i]));
-    memcpy(v.hb->end, HBYTES(strv[i]).start, tl);
-    v.hb->end += tl;
+    tl= cht_hb_len(OBJ_HBYTES(strv[i]));
+    memcpy(dest, cht_hb_data(OBJ_HBYTES(strv[i])), tl);
+    dest += tl;
   }
-  return TCL_OK;
-}  
+}
 
-int do_hbytes_append(ClientData cd, Tcl_Interp *ip,
-		     HBytes_Var v, int strc, Tcl_Obj *const *strv) {
-  return app_pre(cd,ip,1,v,strc,strv);
+int cht_do_hbytes_prepend(ClientData cd, Tcl_Interp *ip,
+		      HBytes_Var v, int strc, Tcl_Obj *const *strv) {
+  int rc, el;
+  Byte *dest;
+  
+  rc= strs1(ip,strc,strv,&el);  if (rc) return rc;
+  dest= cht_hb_prepend(v.hb, el);
+  strs2(dest, strc,strv);
+  return TCL_OK;
 }
   
-int do_hbytes_prepend(ClientData cd, Tcl_Interp *ip,
-		      HBytes_Var v, int strc, Tcl_Obj *const *strv) {
-  return app_pre(cd,ip,0,v,strc,strv);
+int cht_do_hbytes_append(ClientData cd, Tcl_Interp *ip,
+		     HBytes_Var v, int strc, Tcl_Obj *const *strv) {
+  int rc, el;
+  Byte *dest;
+
+  rc= strs1(ip,strc,strv,&el);  if (rc) return rc;
+  dest= cht_hb_append(v.hb, el);
+  strs2(dest,  strc,strv);
+  return TCL_OK;
 }
 
-int do_hbytes_concat(ClientData cd, Tcl_Interp *ip,
+int cht_do_hbytes_concat(ClientData cd, Tcl_Interp *ip,
 		     int strc, Tcl_Obj *const *strv, HBytes_Value *result) {
-  HBytes_Var fake;
+  int rc, l;
+  Byte *dest;
   
-  result->start= result->end= 0;
-  fake.hb= result;
-  return app_pre(cd,ip,1,fake,strc,strv);
+  rc= strs1(ip,strc,strv,&l);  if (rc) return rc;
+  dest= cht_hb_arrayspace(result,l);
+  strs2(dest, strc,strv);
+  return TCL_OK;
+}
+
+static int underrun(Tcl_Interp *ip) {
+  return cht_staticerr(ip,"data underrun","HBYTES LENGTH UNDERRUN");
 }
 
+int cht_do_hbytes_unprepend(ClientData cd, Tcl_Interp *ip,
+			HBytes_Var v, int preflength, HBytes_Value *result) {
+  const Byte *rdata= cht_hb_unprepend(v.hb, preflength);
+  if (!rdata) return underrun(ip);
+  cht_hb_array(result, rdata, preflength);
+  return TCL_OK;
+}
+
+int cht_do_hbytes_unappend(ClientData cd, Tcl_Interp *ip,
+		       HBytes_Var v, int suflength, HBytes_Value *result) {
+  const Byte *rdata= cht_hb_unappend(v.hb, suflength);
+  if (!rdata) return underrun(ip);
+  cht_hb_array(result, rdata, suflength);
+  return TCL_OK;
+}
+
+int cht_do_hbytes_chopto(ClientData cd, Tcl_Interp *ip,
+		     HBytes_Var v, int newlength, HBytes_Value *result) {
+  int suflength= cht_hb_len(v.hb) - newlength;
+  return cht_do_hbytes_unappend(0,ip,v, suflength, result);
+}