Add compat mode for old (32bit FileSize) CacheDB (LP: #1274466)

1 files changed, 19 insertions, 1 deletions

diff --git a/ftparchive/cachedb.h b/ftparchive/cachedb.h
index edb8594bf..29d710d2c 100644
--- a/ftparchive/cachedb.h
+++ b/ftparchive/cachedb.h
@@ -85,8 +85,12 @@ class CacheDB
    bool OpenDebFile();
    void CloseDebFile();
 
-   bool GetFileStat(bool const &doStat = false);
+   // GetCurStat needs some compat code, see lp #1274466)
+   bool GetCurStatCompatOldFormat();
+   bool GetCurStatCompatNewFormat();
    bool GetCurStat();
+
+   bool GetFileStat(bool const &doStat = false);
    bool LoadControl();
    bool LoadContents(bool const &GenOnly);
    bool LoadSource();
@@ -101,6 +105,20 @@ class CacheDB
                   FlSHA512=(1<<6), FlSource=(1<<7),
    };
 
+   // the on-disk format changed (FileSize increased to 64bit) in 
+   // commit 650faab0 which will lead to corruption with old caches
+   struct StatStoreOldFormat
+   {
+      uint32_t Flags;
+      uint32_t mtime;
+      uint32_t FileSize;
+      uint8_t  MD5[16];
+      uint8_t  SHA1[20];
+      uint8_t  SHA256[32];
+   } CurStatOldFormat;
+
+   // WARNING: this struct is read/written to the DB so do not change the
+   //          layout of the fields (see lp #1274466), only append to it
    struct StatStore
    {
       uint32_t Flags;