odb_loose: fsync tests

Introduce a simple counter that `p_fsync` implements.  This is useful
for ensuring that `p_fsync` is called when we expect it to be, for
example when we have enabled an odb backend to perform `fsync`s when
writing objects.

4 files changed, 16 insertions, 1 deletions

diff --git a/src/posix.c b/src/posix.c
index e68f324f6..94deb6ab0 100644
--- a/src/posix.c
+++ b/src/posix.c
@@ -10,6 +10,8 @@
 #include <stdio.h>
 #include <ctype.h>
 
+size_t p_fsync__cnt = 0;
+
 #ifndef GIT_WIN32
 
 #ifdef NO_ADDRINFO
diff --git a/src/posix.h b/src/posix.h
index f204751cf..bd5a98e26 100644
--- a/src/posix.h
+++ b/src/posix.h
@@ -111,6 +111,12 @@ extern int p_rename(const char *from, const char *to);
 extern int git__page_size(size_t *page_size);
 extern int git__mmap_alignment(size_t *page_size);
 
+/* The number of times `p_fsync` has been called.  Note that this is for
+ * test code only; it it not necessarily thread-safe and should not be
+ * relied upon in production.
+ */
+extern size_t p_fsync__cnt;
+
 /**
  * Platform-dependent methods
  */
diff --git a/src/unix/posix.h b/src/unix/posix.h
index b4786403f..52985fd8a 100644
--- a/src/unix/posix.h
+++ b/src/unix/posix.h
@@ -40,9 +40,14 @@ typedef int GIT_SOCKET;
 #define p_link(o,n) link(o, n)
 #define p_unlink(p) unlink(p)
 #define p_mkdir(p,m) mkdir(p, m)
-#define p_fsync(fd) fsync(fd)
 extern char *p_realpath(const char *, char *);
 
+GIT_INLINE(int) p_fsync(int fd)
+{
+	p_fsync__cnt++;
+	return fsync(fd);
+}
+
 #define p_recv(s,b,l,f) recv(s,b,l,f)
 #define p_send(s,b,l,f) send(s,b,l,f)
 #define p_inet_pton(a, b, c) inet_pton(a, b, c)
diff --git a/src/win32/posix_w32.c b/src/win32/posix_w32.c
index fea634b00..5172627b0 100644
--- a/src/win32/posix_w32.c
+++ b/src/win32/posix_w32.c
@@ -113,6 +113,8 @@ int p_fsync(int fd)
 {
 	HANDLE fh = (HANDLE)_get_osfhandle(fd);
 
+	p_fsync__cnt++;
+
 	if (fh == INVALID_HANDLE_VALUE) {
 		errno = EBADF;
 		return -1;