X-Git-Url: https://git.sesse.net/?a=blobdiff_plain;f=futatabi%2Fframe_on_disk.h;h=f74cb86f717161a9b6a9ffab8575594a5a8548b4;hb=b3a7a9eddd8b800f1b921332e8fdacb72e0d9b20;hp=184385792528130df7e3ba16637385c0c14a35db;hpb=6e116a6bbeb2c047a3bfb084395ec601ce211e6c;p=nageru

diff --git a/futatabi/frame_on_disk.h b/futatabi/frame_on_disk.h
index 1843857..f74cb86 100644
--- a/futatabi/frame_on_disk.h
+++ b/futatabi/frame_on_disk.h
@@ -1,24 +1,32 @@
 #ifndef _FRAME_ON_DISK_H
 #define _FRAME_ON_DISK_H 1
 
+#include "defs.h"
+
+#include <algorithm>
 #include <mutex>
+#include <stdint.h>
 #include <string>
 #include <vector>
 
-#include <stdint.h>
-
-#include "defs.h"
-
 extern std::mutex frame_mu;
 struct FrameOnDisk {
-        int64_t pts = -1;  // -1 means empty.
-        off_t offset;
-        unsigned filename_idx;
-        uint32_t size;  // Not using size_t saves a few bytes; we can have so many frames.
+	int64_t pts = -1;  // -1 means empty.
+	off_t offset;
+	unsigned filename_idx;
+	uint32_t size;  // Not using size_t saves a few bytes; we can have so many frames.
 };
 extern std::vector<FrameOnDisk> frames[MAX_STREAMS];  // Under frame_mu.
 extern std::vector<std::string> frame_filenames;  // Under frame_mu.
 
+static bool inline operator==(const FrameOnDisk &a, const FrameOnDisk &b)
+{
+	return a.pts == b.pts &&
+		a.offset == b.offset &&
+		a.filename_idx == b.filename_idx &&
+		a.size == b.size;
+}
+
 // A helper class to read frames from disk. It caches the file descriptor
 // so that the kernel has a better chance of doing readahead when it sees
 // the sequential reads. (For this reason, each display has a private
@@ -26,6 +34,7 @@ extern std::vector<std::string> frame_filenames;  // Under frame_mu.
 // for a single .frames file.)
 class FrameReader {
 public:
+	FrameReader();
 	~FrameReader();
 	std::string read_frame(FrameOnDisk frame);
 
@@ -34,4 +43,19 @@ private:
 	int last_filename_idx = -1;
 };
 
+// Utility functions for dealing with binary search.
+inline std::vector<FrameOnDisk>::iterator
+find_last_frame_before(std::vector<FrameOnDisk> &frames, int64_t pts_origin)
+{
+	return std::lower_bound(frames.begin(), frames.end(), pts_origin,
+	                        [](const FrameOnDisk &frame, int64_t pts) { return frame.pts < pts; });
+}
+
+inline std::vector<FrameOnDisk>::iterator
+find_first_frame_at_or_after(std::vector<FrameOnDisk> &frames, int64_t pts_origin)
+{
+	return std::upper_bound(frames.begin(), frames.end(), pts_origin - 1,
+	                        [](int64_t pts, const FrameOnDisk &frame) { return pts < frame.pts; });
+}
+
 #endif  // !defined(_FRAME_ON_DISK_H)