From 3794aa7ac7d92cadfd446a3ff8b00de838885ace Mon Sep 17 00:00:00 2001
From: ed <s@ocv.me>
Date: Tue, 2 Jul 2019 22:58:31 +0000
Subject: [PATCH] support repetitive files

---
 copyparty/httpcli.py | 42 +++++++++++++++++++++++++++++++-----------
 copyparty/up2k.py    | 27 ++++++++++++++++++---------
 2 files changed, 49 insertions(+), 20 deletions(-)

diff --git a/copyparty/httpcli.py b/copyparty/httpcli.py
index bc4447aa..9abd8a33 100644
--- a/copyparty/httpcli.py
+++ b/copyparty/httpcli.py
@@ -282,7 +282,7 @@ class HttpCli(object):
 
         x = self.conn.hsrv.broker.put(True, "up2k.handle_chunk", wark, chash)
         response = x.get()
-        chunksize, ofs, path = response
+        chunksize, cstart, path = response
 
         if self.args.nw:
             path = os.devnull
@@ -290,21 +290,40 @@ class HttpCli(object):
         if remains > chunksize:
             raise Pebkac(400, "your chunk is too big to fit")
 
-        self.log("writing {} #{} @{} len {}".format(path, chash, ofs, remains))
+        self.log("writing {} #{} @{} len {}".format(path, chash, cstart, remains))
 
         reader = read_socket(self.sr, remains)
 
-        with open(path, "rb+") as f:
-            f.seek(ofs)
+        with open(path, "rb+", 512 * 1024) as f:
+            f.seek(cstart[0])
             post_sz, _, sha_b64 = hashcopy(self.conn, reader, f)
 
-        if sha_b64 != chash:
-            raise Pebkac(
-                400,
-                "your chunk got corrupted somehow:\n{} expected,\n{} received ({} bytes)".format(
-                    chash, sha_b64, post_sz
-                ),
-            )
+            if sha_b64 != chash:
+                raise Pebkac(
+                    400,
+                    "your chunk got corrupted somehow:\n{} expected,\n{} received ({} bytes)".format(
+                        chash, sha_b64, post_sz
+                    ),
+                )
+
+            if len(cstart) > 1:
+                self.log(
+                    "clone {} to {}".format(
+                        cstart[0], " & ".join(str(x) for x in cstart[1:])
+                    )
+                )
+                ofs = 0
+                while ofs < chunksize:
+                    bufsz = min(chunksize - ofs, 4 * 1024 * 1024)
+                    f.seek(cstart[0] + ofs)
+                    buf = f.read(bufsz)
+                    for wofs in cstart[1:]:
+                        f.seek(wofs + ofs)
+                        f.write(buf)
+
+                    ofs += len(buf)
+
+                self.log("clone {} done".format(cstart[0]))
 
         x = self.conn.hsrv.broker.put(True, "up2k.confirm_chunk", wark, chash)
         response = x.get()
@@ -652,3 +671,4 @@ class HttpCli(object):
         )
         self.reply(html.encode("utf-8", "replace"))
         return True
+
diff --git a/copyparty/up2k.py b/copyparty/up2k.py
index 6d744538..fe8d4b4a 100644
--- a/copyparty/up2k.py
+++ b/copyparty/up2k.py
@@ -56,15 +56,24 @@ class Up2k(object):
                     "name": cj["name"],
                     "size": cj["size"],
                     "hash": deepcopy(cj["hash"]),
-                    # upload state
-                    "pend": deepcopy(cj["hash"]),
                 }
+
+                # one chunk may occur multiple times in a file;
+                # filter to unique values for the list of missing chunks
+                # (preserve order to reduce disk thrashing)
+                job["need"] = []
+                lut = {}
+                for k in cj["hash"]:
+                    if k not in lut:
+                        job["need"].append(k)
+                        lut[k] = 1
+
                 self._new_upload(job)
 
             return {
                 "name": job["name"],
                 "size": job["size"],
-                "hash": job["pend"],
+                "hash": job["need"],
                 "wark": wark,
             }
 
@@ -74,16 +83,15 @@ class Up2k(object):
             if not job:
                 raise Pebkac(404, "unknown wark")
 
-            if chash not in job["pend"]:
+            if chash not in job["need"]:
                 raise Pebkac(200, "already got that but thanks??")
 
-            try:
-                nchunk = job["hash"].index(chash)
-            except ValueError:
+            nchunk = [n for n, v in enumerate(job["hash"]) if v == chash]
+            if not nchunk:
                 raise Pebkac(404, "unknown chunk")
 
         chunksize = self._get_chunksize(job["size"])
-        ofs = nchunk * chunksize
+        ofs = [chunksize * x for x in nchunk]
 
         path = os.path.join(job["vdir"], job["name"])
 
@@ -91,7 +99,7 @@ class Up2k(object):
 
     def confirm_chunk(self, wark, chash):
         with self.mutex:
-            self.registry[wark]["pend"].remove(chash)
+            self.registry[wark]["need"].remove(chash)
 
     def _get_chunksize(self, filesize):
         chunksize = 1024 * 1024
@@ -131,3 +139,4 @@ class Up2k(object):
         with open(path, "wb") as f:
             f.seek(job["size"] - 1)
             f.write(b"e")
+