1 files changed, 94 insertions, 0 deletions
diff --git a/src/util/filebuf.h b/src/util/filebuf.h
new file mode 100644
index 000000000..4a61ae4e3
--- /dev/null
+++ b/src/util/filebuf.h
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) the libgit2 contributors. All rights reserved.
+ *
+ * This file is part of libgit2, distributed under the GNU GPL v2 with
+ * a Linking Exception. For full terms see the included COPYING file.
+ */
+#ifndef INCLUDE_filebuf_h__
+#define INCLUDE_filebuf_h__
+
+#include "git2_util.h"
+
+#include "futils.h"
+#include "hash.h"
+#include <zlib.h>
+
+#ifdef GIT_THREADS
+#	define GIT_FILEBUF_THREADS
+#endif
+
+#define GIT_FILEBUF_HASH_CONTENTS		(1 << 0)
+#define GIT_FILEBUF_APPEND				(1 << 2)
+#define GIT_FILEBUF_CREATE_LEADING_DIRS	(1 << 3)
+#define GIT_FILEBUF_TEMPORARY			(1 << 4)
+#define GIT_FILEBUF_DO_NOT_BUFFER		(1 << 5)
+#define GIT_FILEBUF_FSYNC				(1 << 6)
+#define GIT_FILEBUF_DEFLATE_SHIFT		(7)
+
+#define GIT_FILELOCK_EXTENSION ".lock\0"
+#define GIT_FILELOCK_EXTLENGTH 6
+
+typedef struct git_filebuf git_filebuf;
+struct git_filebuf {
+	char *path_original;
+	char *path_lock;
+
+	int (*write)(git_filebuf *file, void *source, size_t len);
+
+	bool compute_digest;
+	git_hash_ctx digest;
+
+	unsigned char *buffer;
+	unsigned char *z_buf;
+
+	z_stream zs;
+	int flush_mode;
+
+	size_t buf_size, buf_pos;
+	git_file fd;
+	bool fd_is_open;
+	bool created_lock;
+	bool did_rename;
+	bool do_not_buffer;
+	bool do_fsync;
+	int last_error;
+};
+
+#define GIT_FILEBUF_INIT {0}
+
+/*
+ * The git_filebuf object lifecycle is:
+ * - Allocate git_filebuf, preferably using GIT_FILEBUF_INIT.
+ *
+ * - Call git_filebuf_open() to initialize the filebuf for use.
+ *
+ * - Make as many calls to git_filebuf_write(), git_filebuf_printf(),
+ *   git_filebuf_reserve() as you like. The error codes for these
+ *   functions don't need to be checked. They are stored internally
+ *   by the file buffer.
+ *
+ * - While you are writing, you may call git_filebuf_hash() to get
+ *   the hash of all you have written so far. This function will
+ *   fail if any of the previous writes to the buffer failed.
+ *
+ * - To close the git_filebuf, you may call git_filebuf_commit() or
+ *   git_filebuf_commit_at() to save the file, or
+ *   git_filebuf_cleanup() to abandon the file.  All of these will
+ *   free the git_filebuf object. Likewise, all of these will fail
+ *   if any of the previous writes to the buffer failed, and set
+ *   an error code accordingly.
+ */
+int git_filebuf_write(git_filebuf *lock, const void *buff, size_t len);
+int git_filebuf_reserve(git_filebuf *file, void **buff, size_t len);
+int git_filebuf_printf(git_filebuf *file, const char *format, ...) GIT_FORMAT_PRINTF(2, 3);
+
+int git_filebuf_open(git_filebuf *lock, const char *path, int flags, mode_t mode);
+int git_filebuf_open_withsize(git_filebuf *file, const char *path, int flags, mode_t mode, size_t size);
+int git_filebuf_commit(git_filebuf *lock);
+int git_filebuf_commit_at(git_filebuf *lock, const char *path);
+void git_filebuf_cleanup(git_filebuf *lock);
+int git_filebuf_hash(unsigned char *out, git_filebuf *file);
+int git_filebuf_flush(git_filebuf *file);
+int git_filebuf_stats(time_t *mtime, size_t *size, git_filebuf *file);
+
+#endif