[Libguestfs] [nbdkit PATCH 1/3] vector: Add VECT_remove

[Eric Blake]

An upcoming patch wants to remove an arbitrary element from a vector.

Also, add testsuite coverage for other functions added since the
original unit test was written.  It's a bit awkward that the compare
for VECT_search and VECT_sort differ in type, but such is life (we
indeed have search code where typing the key differently is useful).

Signed-off-by: Eric Blake <eblake at redhat.com>
---
 common/utils/vector.h      | 10 ++++++++++
 common/utils/test-vector.c | 26 +++++++++++++++++++++++++-
 2 files changed, 35 insertions(+), 1 deletion(-)

diff --git a/common/utils/vector.h b/common/utils/vector.h
index c14644a7..880fd308 100644
--- a/common/utils/vector.h
+++ b/common/utils/vector.h
@@ -125,6 +125,16 @@
       f (v->ptr[i]);                                                    \
   }                                                                     \
                                                                         \
+  /* Remove i'th element.  i=0 => beginning  i=size-1 => end */         \
+  static inline int                                                     \
+  name##_remove (name *v, size_t i)                                     \
+  {                                                                     \
+    if (i >= v->size) return -1;                                        \
+    memmove (&v->ptr[i], &v->ptr[i+1], (v->size-i) * sizeof (type));    \
+    v->size--;                                                          \
+    return 0;                                                           \
+  }                                                                     \
+                                                                        \
   /* Sort the elements of the vector. */                                \
   static inline void                                                    \
   name##_sort (name *v,                                                 \
diff --git a/common/utils/test-vector.c b/common/utils/test-vector.c
index 7b0a7424..a87f89ec 100644
--- a/common/utils/test-vector.c
+++ b/common/utils/test-vector.c
@@ -43,19 +43,43 @@
 DEFINE_VECTOR_TYPE(int64_vector, int64_t);
 DEFINE_VECTOR_TYPE(string_vector, char *);

+static int
+compare (const int64_t *a, const int64_t *b)
+{
+  return (*a > *b) - (*a < *b);
+}
+
 static void
 test_int64_vector (void)
 {
   int64_vector v = empty_vector;
   size_t i;
   int r;
+  int64_t tmp, *p;

   for (i = 0; i < 10; ++i) {
-    r = int64_vector_append (&v, i);
+    r = int64_vector_insert (&v, i, 0);
     assert (r == 0);
   }
+
+  for (i = 0; i < 10; ++i)
+    assert (v.ptr[i] == 9 - i);
+  int64_vector_sort (&v, compare);
   for (i = 0; i < 10; ++i)
     assert (v.ptr[i] == i);
+
+  r = int64_vector_remove (&v, 1);
+  assert (r == 0);
+  assert (v.size == 9);
+  assert (v.ptr[1] == 2);
+
+  tmp = 10;
+  p = int64_vector_search (&v, &tmp, (void*) compare);
+  assert (p == NULL);
+  tmp = 8;
+  p = int64_vector_search (&v, &tmp, (void*) compare);
+  assert (p == &v.ptr[7]);
+
   free (v.ptr);
 }

-- 
2.27.0