Add atomic_rm_rf and atomic_rm_rf_tmp

1 files changed, 32 insertions, 0 deletions

diff --git a/src/libunixonacid/atomic_rm_rf_tmp.c b/src/libunixonacid/atomic_rm_rf_tmp.c
new file mode 100644
index 0000000..8be5189
--- /dev/null
+++ b/src/libunixonacid/atomic_rm_rf_tmp.c
@@ -0,0 +1,32 @@
+/* ISC license. */
+
+#include <errno.h>
+#include <stdio.h>
+#include <skalibs/stralloc.h>
+#include <skalibs/djbunix.h>
+#include <skalibs/random.h>
+#include <skalibs/unix-transactional.h>
+
+int atomic_rm_rf_tmp (char const *filename, stralloc *tmp)
+{
+  unsigned int tmpbase = tmp->len ;
+  unsigned int start ;
+  if (!stralloc_cats(tmp, ".skalibs-rmrf-")
+   || !stralloc_cats(tmp, filename)) return -1 ;
+  start = tmp->len ;
+  for (;;)
+  {
+    if (random_sauniquename(tmp, 64) < 0) goto err ;
+    if (!stralloc_0(tmp)) goto err ;
+    if (!rename(filename, tmp->s + tmpbase)) break ;
+    if (errno != EEXIST && errno != ENOTEMPTY) goto err ;
+    tmp->len = start ;
+  }
+  if (rm_rf_in_tmp(tmp, tmpbase) < 0) goto err ;
+  tmp->len = tmpbase ;
+  return 0 ;
+
+err:
+  tmp->len = tmpbase ;
+  return -1 ;
+}