new files that may replace GSList in relaycon

If I want to move relaycon into common so Android can use it (assuming
the jni code starts including json-c and libcurl so it can handle
networking) I'll need a replacement for GSList. This is a start.

xwords4/common/xwlist.c

@@ -0,0 +1,127 @@
+/* -*-mode: C; fill-column: 78; c-basic-offset: 4; -*- */
+/* 
+ * Copyright 2009 by Eric House (xwords@eehouse.org).  All rights reserved.
+ *
+ * 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 program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#include "xwlist.h"
+
+#define MAX_HERE 16
+
+typedef struct XWList {
+    XP_U16 len;
+    XP_U16 size;
+    elem* list;
+    MPSLOT
+} XWList;
+
+XWList*
+mk_list(MPFORMAL XP_U16 XP_UNUSED(sizeHint))
+{
+    XWList* list = XP_CALLOC( mpool, sizeof(*list));
+    MPASSIGN( list->mpool, mpool);
+    return list;
+}
+
+void
+list_append( XWList* self, elem one )
+{
+    if ( self->size == 0 ) { /* initial case */
+        self->size = 2;
+        self->list = XP_MALLOC( self->mpool, self->size * sizeof(self->list[0]) );
+    }
+    if ( self->len == self->size ) { /* need to grow? */
+        self->size *= 2;
+        self->list = XP_REALLOC( self->mpool, self->list, self->size * sizeof(self->list[0]) );
+    }
+        
+    self->list[self->len++] = one;
+    XP_LOGF( "%s(): put %p at position %d (size: %d)", __func__, one, self->len-1, self->size );
+}
+
+XP_U16
+list_get_len( const XWList* list )
+{
+    return list->len;
+}
+
+void
+list_remove_front( XWList* self, elem* out, XP_U16* countp )
+{
+    const XP_U16 nMoved = XP_MIN( *countp, self->len );
+    XP_MEMCPY( out, self->list, nMoved * sizeof(out[0]) );
+    *countp = nMoved;
+
+    // Now copy the survivors down
+    self->len -= nMoved;
+    XP_MEMMOVE( &self->list[0], &self->list[nMoved], self->len * sizeof(self->list[0]));
+}
+
+void
+list_remove_back(XWList* XP_UNUSED(self), elem* XP_UNUSED(here), XP_U16* XP_UNUSED(count))
+{
+}
+
+void
+list_free( XWList* self, destructor proc, void* closure )
+{
+    if ( !!proc ) {
+        for ( XP_U16 ii = 0; ii < self->len; ++ii ) {
+            (*proc)(self->list[ii], closure);
+        }
+    }
+
+    if ( !!self->list ) {
+        XP_FREE( self->mpool, self->list );
+    }
+    XP_FREE( self->mpool, self );
+}
+
+#ifdef DEBUG
+
+static void
+dest(elem elem, void* XP_UNUSED(closure))
+{
+    XP_LOGF( "%s(%p)", __func__, elem);
+}
+
+void
+list_test_lists(MPFORMAL_NOCOMMA)
+{
+    XWList* list = mk_list( mpool, 16 );
+    for ( char* ii = 0; ii < (char*)100; ++ii ) {
+        (void)list_append( list, ii );
+    }
+
+    XP_ASSERT( list_get_len(list) == 100 );
+
+    char* prev = 0;
+    while ( 0 < list_get_len( list ) ) {
+        elem here;
+        XP_U16 count = 1;
+        list_remove_front( list, &here, &count );
+        XP_LOGF( "%s(): got here: %p", __func__, here );
+        XP_ASSERT( count == 1 );
+        XP_ASSERT( prev++ == here );
+    }
+
+    for ( char* ii = 0; ii < (char*)10; ++ii ) {
+        (void)list_append( list, ii );
+    }
+
+    list_free( list, dest, NULL );
+}
+#endif

xwords4/common/xwlist.h

@@ -0,0 +1,44 @@
+/* -*-mode: C; fill-column: 78; c-basic-offset: 4; -*- */
+/* 
+ * Copyright 2017 by Eric House (xwords@eehouse.org).  All rights reserved.
+ *
+ * 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 program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#ifndef _XWLIST_H_
+#define _XWLIST_H_
+
+#include "comtypes.h"
+#include "mempool.h"
+
+#include "xptypes.h"
+
+typedef void* elem;
+typedef struct XWList XWList;
+typedef void (*destructor)(elem one, void* closure);
+
+XWList* mk_list(MPFORMAL XP_U16 sizeHint);
+void list_free(XWList* list, destructor proc, void* closure);
+
+void list_append(XWList* list, elem one);
+XP_U16 list_get_len(const XWList* list);
+void list_remove_front(XWList* list, elem* here, XP_U16* count);
+void list_remove_back(XWList* list, elem* here, XP_U16* count);
+
+#ifdef DEBUG
+void list_test_lists(MPFORMAL_NOCOMMA);
+#endif
+
+#endif