added "place=header" (in addition to "place=end" attribuite value) to print code block as a header in spice netlists

src/spice.awk

@@ -141,6 +141,10 @@ function process(        i, iprefix)
     spiceprefix=$3
     return
   }
+  if($0 ~/\*\*\*\* begin user header code/){ #20180129
+    user_code=1
+    return
+  }
   if($0 ~/\*\*\*\* begin user architecture code/){ #20180129
     user_code=1
     print
@@ -151,6 +155,10 @@ function process(        i, iprefix)
     print
     return
   }
+  if($0 ~/\*\*\*\* end user header code/){ #20180129
+    user_code=0
+    return
+  }
   if(user_code) { #20180129
     print
     return

src/spice_netlist.c

@@ -152,6 +152,32 @@ void global_spice_netlist(int global)  /* netlister driver */
    dbg(0, "global_spice_netlist(): problems opening netlist file\n");
    return;
  }
+
+
+
+ first = 0;
+ for(i=0;i<xctx->instances;i++) /* print netlist_commands of top level cell with 'place=header' property */
+ {
+  if( strcmp(get_tok_value(xctx->inst[i].prop_ptr,"spice_ignore",0),"true")==0 ) continue;
+  if(xctx->inst[i].ptr<0) continue;
+  if(!strcmp(get_tok_value( (xctx->inst[i].ptr+ xctx->sym)->prop_ptr, "spice_ignore",0 ), "true") ) {
+    continue;
+  }
+  my_strdup(1264, &type,(xctx->inst[i].ptr+ xctx->sym)->type);
+  my_strdup(1265, &place,get_tok_value((xctx->inst[i].ptr+ xctx->sym)->prop_ptr,"place",0));
+  if( type && !strcmp(type,"netlist_commands") ) {
+   if(!place) {
+     my_strdup(1266, &place,get_tok_value(xctx->inst[i].prop_ptr,"place",0));
+   }
+   if(place && !strcmp(place, "header" )) {
+     if(first == 0) fprintf(fd,"**** begin user header code\n");
+     first++;
+     print_spice_element(fd, i) ;  /* this is the element line  */
+   }
+  }
+ }
+ if(first) fprintf(fd,"**** end user header code\n");
+
  /* netlist_options */
  for(i=0;i<xctx->instances;i++) {
    if(!(xctx->inst[i].ptr+ xctx->sym)->type) continue;
@@ -188,7 +214,8 @@ void global_spice_netlist(int global)  /* netlister driver */
  spice_netlist(fd, 0);
 
  first = 0;
- for(i=0;i<xctx->instances;i++) /* print netlist_commands of top level cell with no 'place=end' property */
+ for(i=0;i<xctx->instances;i++) /* print netlist_commands of top level cell with no 'place=end' property
+                                   and no place=header */
  {
   if( strcmp(get_tok_value(xctx->inst[i].prop_ptr,"spice_ignore",0),"true")==0 ) continue;
   if(xctx->inst[i].ptr<0) continue;
@@ -198,13 +225,13 @@ void global_spice_netlist(int global)  /* netlister driver */
   my_strdup(381, &type,(xctx->inst[i].ptr+ xctx->sym)->type);
   my_strdup(382, &place,get_tok_value((xctx->inst[i].ptr+ xctx->sym)->prop_ptr,"place",0));
   if( type && !strcmp(type,"netlist_commands") ) {
-   if(!place || strcmp(place, "end" )) {
+   if(!place) {
      my_strdup(383, &place,get_tok_value(xctx->inst[i].prop_ptr,"place",0));
-     if(!place || strcmp(place, "end" )) {
-       if(first == 0) fprintf(fd,"**** begin user architecture code\n");
-       first++;
-       print_spice_element(fd, i) ;  /* this is the element line  */
-     }
+   }
+   if(!place || (strcmp(place, "end") && strcmp(place, "header")) ) {
+     if(first == 0) fprintf(fd,"**** begin user architecture code\n");
+     first++;
+     print_spice_element(fd, i) ;  /* this is the element line  */
    }
   }
  }

xschem_library/examples/cmos_example.sch

@@ -6,6 +6,10 @@ S {}
 E {}
 T {CMOS DIFFERENTIAL AMPLIFIER
 EXAMPLE} 250 -650 0 0 0.4 0.4 {}
+T {This is an example of a code block that will
+be placed as a header in the netlist.
+use 'place=header' attribute and set the
+header text as a 'value' attribute} 720 -720 0 0 0.4 0.4 {}
 N 30 -310 30 -280 {lab=VCC}
 N 30 -310 60 -310 {lab=VCC}
 N 260 -240 260 -190 {lab=GN}
@@ -108,3 +112,9 @@ C {ngspice_probe.sym} 600 -260 0 0 {name=r3}
 C {ngspice_probe.sym} 770 -420 0 0 {name=r4}
 C {ngspice_get_value.sym} 620 -160 0 0 {name=r5 node=i(@$\{path\}m1[id])
 descr="I="}
+C {code.sym} 920 -580 0 0 {name=HEADER
+place=header
+only_toplevel=true
+value="** ======================== **
+** This is a netlist header **
+** ======================== **"}