libdpkg: Add a size argument to varbufinit

Change modstatdb_init to use varbufinit instead of its own
initialization.

ChangeLog

@@ -1,3 +1,12 @@
+2008-06-04  Guillem Jover  <guillem@debian.org>
+
+	* lib/dpkg-db.h (varbufinit): Add a size argument, fix all callers.
+	(varbuf::init): Add an optional size argument.
+	(varbuf::varbuf): Likewise.
+	* lib/varbuf.c (varbufinit): Allocate a buffer if size is not zero.
+	* lib/dbmodify.c (modstatdb_init): Use varbufinit instead of its
+	own initialization.
+
 2008-06-04  Guillem Jover  <guillem@debian.org>
 
 	* lib/dpkg-db.h (VARBUF_INIT): New macro.

lib/dbmodify.c

@@ -191,9 +191,7 @@ enum modstatdb_rw modstatdb_init(const char *adir, enum modstatdb_rw readwritere
 
   if (cstatus >= msdbrw_write) {
     createimptmp();
-    uvb.used= 0;
-    uvb.size= 10240;
-    uvb.buf= m_malloc(uvb.size);
+    varbufinit(&uvb, 10240);
   }
 
   trig_incorporate(cstatus, admindir);

lib/dpkg-db.h

@@ -372,7 +372,7 @@ extern void varbufaddc(struct varbuf *v, int c);
 extern void varbufdupc(struct varbuf *v, int c, ssize_t s);
 int varbufprintf(struct varbuf *v, const char *fmt, ...) PRINTFFORMAT(2,3);
 int varbufvprintf(struct varbuf *v, const char *fmt, va_list va);
-void varbufinit(struct varbuf *v);
+void varbufinit(struct varbuf *v, size_t size);
 void varbufreset(struct varbuf *v);
 void varbufextend(struct varbuf *v);
 void varbuffree(struct varbuf *v);
@@ -399,9 +399,9 @@ struct varbuf {
   char *buf;
 
 #ifdef __cplusplus
-  void init() { varbufinit(this); }
+  void init(size_t _size = 0) { varbufinit(this, _size); }
   void free() { varbuffree(this); }
-  varbuf() { varbufinit(this); }
+  varbuf(size_t _size = 0) { varbufinit(this, _size); }
   ~varbuf() { varbuffree(this); }
   void operator()(int c) { varbufaddc(this,c); }
   void operator()(const char *s) { varbufaddstr(this,s); }

lib/varbuf.c

@@ -87,10 +87,15 @@ void varbufaddbuf(struct varbuf *v, const void *s, const int l) {
   memcpy(v->buf + ou, s, l);
 }
 
-void varbufinit(struct varbuf *v) {
-  /* NB: dbmodify.c does its own init to get a big buffer */
-  v->size= v->used= 0;
-  v->buf= NULL;
+void
+varbufinit(struct varbuf *v, size_t size)
+{
+  v->used = 0;
+  v->size = size;
+  if (size)
+    v->buf = m_malloc(size);
+  else
+    v->buf = NULL;
 }
 
 void varbufreset(struct varbuf *v) {