bitmap: Use g_try_new0/g_new0/g_renew

Avoids an explicit use of sizeof().  The GLib allocation macros
ensure that the multiplication by the size of the element
uses the right type and does not overflow.

While at it, change bitmap_new() to use g_new0 directly.  Its current
impl of calling bitmap_try_new() followed by a plain abort() has
worse diagnostics than g_new0, which uses g_error to report the actual
allocation size that failed.

Cc: qemu-trivial@nongnu.org
Cc: Roman Kiryanov <rkir@google.com>
Reviewed-by: Daniel Berrange <berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/include/qemu/bitmap.h b/include/qemu/bitmap.h
index 9780681..1cf2884 100644
--- a/include/qemu/bitmap.h
+++ b/include/qemu/bitmap.h
@@ -92,17 +92,14 @@
 
 static inline unsigned long *bitmap_try_new(long nbits)
 {
-    long len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
-    return g_try_malloc0(len);
+    long nelem = BITS_TO_LONGS(nbits);
+    return g_try_new0(unsigned long, nelem);
 }
 
 static inline unsigned long *bitmap_new(long nbits)
 {
-    unsigned long *ptr = bitmap_try_new(nbits);
-    if (ptr == NULL) {
-        abort();
-    }
-    return ptr;
+    long nelem = BITS_TO_LONGS(nbits);
+    return g_new0(unsigned long, nelem);
 }
 
 static inline void bitmap_zero(unsigned long *dst, long nbits)
@@ -265,10 +262,10 @@
 static inline unsigned long *bitmap_zero_extend(unsigned long *old,
                                                 long old_nbits, long new_nbits)
 {
-    long new_len = BITS_TO_LONGS(new_nbits) * sizeof(unsigned long);
-    unsigned long *new = g_realloc(old, new_len);
-    bitmap_clear(new, old_nbits, new_nbits - old_nbits);
-    return new;
+    long new_nelem = BITS_TO_LONGS(new_nbits);
+    unsigned long *ptr = g_renew(unsigned long, old, new_nelem);
+    bitmap_clear(ptr, old_nbits, new_nbits - old_nbits);
+    return ptr;
 }
 
 void bitmap_to_le(unsigned long *dst, const unsigned long *src,