From: Volker Lendecke <vl@samba.org>
Date: Wed, 25 Mar 2020 21:07:44 +0000 (+0100)
Subject: lib: Add macro ARRAY_DEL_ELEMENT()
X-Git-Url: http://git.samba.org/samba.git/?a=commitdiff_plain;h=94d580c062d7a167a7493542cb746b213880358a;p=bbaumbach%2Fsamba-autobuild%2F.git

lib: Add macro ARRAY_DEL_ELEMENT()

Every time I have to remove an element from within an array I have to
scratch my head about the memmove arguments. Make this easier to use.

Signed-off-by: Volker Lendecke <vl@samba.org>
Reviewed-by: Ralph Boehme <slow@samba.org>
---

diff --git a/lib/replace/replace.h b/lib/replace/replace.h
index 177be37edbe..59f0b60f8a0 100644
--- a/lib/replace/replace.h
+++ b/lib/replace/replace.h
@@ -849,6 +849,12 @@ typedef unsigned long long ptrdiff_t ;
 #endif
 #define ARRAY_SIZE(a) (sizeof(a)/sizeof(a[0]))
 
+/**
+ * Remove an array element by moving the rest one down
+ */
+#define ARRAY_DEL_ELEMENT(a,i,n) \
+if((i)<((n)-1)){memmove(&((a)[(i)]),&((a)[(i)+1]),(sizeof(*(a))*((n)-(i)-1)));}
+
 /**
  * Pointer difference macro
  */
diff --git a/lib/replace/tests/testsuite.c b/lib/replace/tests/testsuite.c
index 7f9801e9f98..2ece95332d2 100644
--- a/lib/replace/tests/testsuite.c
+++ b/lib/replace/tests/testsuite.c
@@ -1095,6 +1095,47 @@ static bool test_closefrom(void)
 	return true;
 }
 
+static bool test_array_del_element(void)
+{
+	int a[] = { 1,2,3,4,5 };
+
+	printf("test: array_del_element\n");
+
+	ARRAY_DEL_ELEMENT(a, 4, ARRAY_SIZE(a));
+
+	if ((a[0] != 1) ||
+	    (a[1] != 2) ||
+	    (a[2] != 3) ||
+	    (a[3] != 4) ||
+	    (a[4] != 5)) {
+		return false;
+	}
+
+	ARRAY_DEL_ELEMENT(a, 0, ARRAY_SIZE(a));
+
+	if ((a[0] != 2) ||
+	    (a[1] != 3) ||
+	    (a[2] != 4) ||
+	    (a[3] != 5) ||
+	    (a[4] != 5)) {
+		return false;
+	}
+
+	ARRAY_DEL_ELEMENT(a, 2, ARRAY_SIZE(a));
+
+	if ((a[0] != 2) ||
+	    (a[1] != 3) ||
+	    (a[2] != 5) ||
+	    (a[3] != 5) ||
+	    (a[4] != 5)) {
+		return false;
+	}
+
+	printf("success: array_del_element\n");
+
+	return true;
+}
+
 bool torture_local_replace(struct torture_context *ctx)
 {
 	bool ret = true;
@@ -1145,6 +1186,7 @@ bool torture_local_replace(struct torture_context *ctx)
 	ret &= test_utimes();
 	ret &= test_memmem();
 	ret &= test_closefrom();
+	ret &= test_array_del_element();
 
 	return ret;
 }