1 files changed, 92 insertions, 0 deletions
diff --git a/compat/win32/dirent.c b/compat/win32/dirent.c
new file mode 100644
index 000000000000..52420ec7d4da
--- /dev/null
+++ b/compat/win32/dirent.c
@@ -0,0 +1,92 @@
+#include "../../git-compat-util.h"
+
+struct DIR {
+	struct dirent dd_dir; /* includes d_type */
+	HANDLE dd_handle;     /* FindFirstFile handle */
+	int dd_stat;          /* 0-based index */
+};
+
+static inline void finddata2dirent(struct dirent *ent, WIN32_FIND_DATAW *fdata)
+{
+	/* convert UTF-16 name to UTF-8 */
+	xwcstoutf(ent->d_name, fdata->cFileName, sizeof(ent->d_name));
+
+	/* Set file type, based on WIN32_FIND_DATA */
+	if (fdata->dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+		ent->d_type = DT_DIR;
+	else
+		ent->d_type = DT_REG;
+}
+
+DIR *opendir(const char *name)
+{
+	wchar_t pattern[MAX_PATH + 2]; /* + 2 for '/' '*' */
+	WIN32_FIND_DATAW fdata;
+	HANDLE h;
+	int len;
+	DIR *dir;
+
+	/* convert name to UTF-16 and check length < MAX_PATH */
+	if ((len = xutftowcs_path(pattern, name)) < 0)
+		return NULL;
+
+	/* append optional '/' and wildcard '*' */
+	if (len && !is_dir_sep(pattern[len - 1]))
+		pattern[len++] = '/';
+	pattern[len++] = '*';
+	pattern[len] = 0;
+
+	/* open find handle */
+	h = FindFirstFileW(pattern, &fdata);
+	if (h == INVALID_HANDLE_VALUE) {
+		DWORD err = GetLastError();
+		errno = (err == ERROR_DIRECTORY) ? ENOTDIR : err_win_to_posix(err);
+		return NULL;
+	}
+
+	/* initialize DIR structure and copy first dir entry */
+	dir = xmalloc(sizeof(DIR));
+	dir->dd_handle = h;
+	dir->dd_stat = 0;
+	finddata2dirent(&dir->dd_dir, &fdata);
+	return dir;
+}
+
+struct dirent *readdir(DIR *dir)
+{
+	if (!dir) {
+		errno = EBADF; /* No set_errno for mingw */
+		return NULL;
+	}
+
+	/* if first entry, dirent has already been set up by opendir */
+	if (dir->dd_stat) {
+		/* get next entry and convert from WIN32_FIND_DATA to dirent */
+		WIN32_FIND_DATAW fdata;
+		if (FindNextFileW(dir->dd_handle, &fdata)) {
+			finddata2dirent(&dir->dd_dir, &fdata);
+		} else {
+			DWORD lasterr = GetLastError();
+			/* POSIX says you shouldn't set errno when readdir can't
+			   find any more files; so, if another error we leave it set. */
+			if (lasterr != ERROR_NO_MORE_FILES)
+				errno = err_win_to_posix(lasterr);
+			return NULL;
+		}
+	}
+
+	++dir->dd_stat;
+	return &dir->dd_dir;
+}
+
+int closedir(DIR *dir)
+{
+	if (!dir) {
+		errno = EBADF;
+		return -1;
+	}
+
+	FindClose(dir->dd_handle);
+	free(dir);
+	return 0;
+}