s3: VFS: shadow_copy2: Add two currently unused functions to make pathnames absolute or relative to $cwd.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=12531

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Uri Simchoni <uri@samba.org>
(backported from commit 9d65107b8f2864dba8d41b3316c483b3f36d0697)

1 files changed, 45 insertions, 0 deletions

diff --git a/source3/modules/vfs_shadow_copy2.c b/source3/modules/vfs_shadow_copy2.c
index 53d3e74c5a0..c03bf465f4a 100644
--- a/source3/modules/vfs_shadow_copy2.c
+++ b/source3/modules/vfs_shadow_copy2.c
@@ -34,6 +34,7 @@
 #include "system/filesys.h"
 #include "include/ntioctl.h"
 #include "util_tdb.h"
+#include "lib/util_path.h"
 
 struct shadow_copy2_config {
 	char *gmt_format;
@@ -219,6 +220,50 @@ static char *shadow_copy2_snapshot_path(TALLOC_CTX *mem_ctx,
 	return result;
 }
 
+static char *make_path_absolute(TALLOC_CTX *mem_ctx,
+				struct shadow_copy2_config *config,
+				const char *name)
+{
+	char *newpath = NULL;
+	char *abs_path = NULL;
+
+	if (name[0] != '/') {
+		newpath = talloc_asprintf(mem_ctx,
+					"%s/%s",
+					config->shadow_cwd,
+					name);
+		if (newpath == NULL) {
+			return NULL;
+		}
+		name = newpath;
+	}
+	abs_path = canonicalize_absolute_path(mem_ctx, name);
+	TALLOC_FREE(newpath);
+	return abs_path;
+}
+
+/* Return a $cwd-relative path. */
+static bool make_relative_path(const char *cwd, char *abs_path)
+{
+	size_t cwd_len = strlen(cwd);
+	size_t abs_len = strlen(abs_path);
+
+	if (abs_len < cwd_len) {
+		return false;
+	}
+	if (memcmp(abs_path, cwd, cwd_len) != 0) {
+		return false;
+	}
+	if (abs_path[cwd_len] != '/' && abs_path[cwd_len] != '\0') {
+		return false;
+	}
+	if (abs_path[cwd_len] == '/') {
+		cwd_len++;
+	}
+	memmove(abs_path, &abs_path[cwd_len], abs_len + 1 - cwd_len);
+	return true;
+}
+
 /**
  * Strip a snapshot component from a filename as
  * handed in via the smb layer.