darray: Add darray_insert() to insert a value at a specified index

This module currently supports removing but not inserting at a
specified index, so this adds that along with some tests. Inserting a
value moves all existing data beyond index over one element.

Signed-off-by: Damien Grassart <damien@grassart.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

diff --git a/ccan/darray/darray.h b/ccan/darray/darray.h
index 75112419dff4a4f11862cb60559b420a86cd7263..fca20b8ad635055f98199afb70f772f1925ff4e5 100644 (file)
--- a/ccan/darray/darray.h
+++ b/ccan/darray/darray.h
@@ -56,6 +56,7 @@
  *
  *     void   darray_append(darray(T) arr, T item);
  *     void   darray_prepend(darray(T) arr, T item);
+ *     void   darray_insert(darray(T) arr, size_t index, T item);
  *     void   darray_push(darray(T) arr, T item); // same as darray_append
  *
  * Insertion (multiple items):
@@ -169,6 +170,12 @@ typedef darray(unsigned long)  darray_ulong;
                memmove((arr).item+1, (arr).item, ((arr).size-1)*sizeof(*(arr).item)); \
                (arr).item[0] = (__VA_ARGS__); \
        } while(0)
+#define darray_insert(arr, index, ...) do { \
+               size_t __index = index; \
+               darray_resize(arr, (arr).size+1); \
+               memmove((arr).item+__index+1, (arr).item+__index, ((arr).size-__index-1)*sizeof(*(arr).item)); \
+               (arr).item[__index] = (__VA_ARGS__); \
+       } while(0)
 #define darray_push(arr, ...) darray_append(arr, __VA_ARGS__)
 
 

diff --git a/ccan/darray/test/run.c b/ccan/darray/test/run.c
index 3d96fa564614cd0b4b987943c48dffb5a9c55f02..5888af60e339afab68f9a5251d58f39af6c06ad9 100644 (file)
--- a/ccan/darray/test/run.c
+++ b/ccan/darray/test/run.c
@@ -38,7 +38,7 @@ int main(void) {
        trace("Generating amalgams (internal)");
        generateAmalgams();
        
-       plan_tests(41);
+       plan_tests(47);
        
        testLits();
        
@@ -70,7 +70,25 @@ int main(void) {
                ok1(darray_size(arr) == 0);
        }
        reset(arr);
-       
+
+       testing(darray_insert);
+       {
+               size_t middle_i;
+
+               for (i=0; i < ARRAY_SIZE(lotsOfNumbers); i++)
+                       darray_insert(arr, i, lotsOfNumbers[i]);
+               ok1(darray_size(arr) == ARRAY_SIZE(lotsOfNumbers));
+               ok1(darray_alloc(arr) >= darray_size(arr));
+               ok1(!memcmp(arr.item, lotsOfNumbers, sizeof(lotsOfNumbers)));
+
+               middle_i = ARRAY_SIZE(lotsOfNumbers) / 2;
+               darray_insert(arr, middle_i, 42);
+               ok1(darray_size(arr) == ARRAY_SIZE(lotsOfNumbers) + 1);
+               ok1(arr.item[middle_i] == 42);
+               ok1(arr.item[middle_i + 1] == lotsOfNumbers[middle_i]);
+       }
+       reset(arr);
+
        testing(darray_from_c, darray_foreach, darray_foreach_reverse);
        {
                long   *i;