support hashes for compressed pdiff files

At the moment we only have hashes for the uncompressed pdiff files, but
via the new '$HASH-Download' field in the .diff/Index hashes can be
provided for the .gz compressed pdiff file, which apt will pick up now
and use to verify the download. Now, we "just" need a buy in from the
creators of repositories…

2 files changed, 15 insertions, 3 deletions

diff --git a/apt-pkg/contrib/hashes.cc b/apt-pkg/contrib/hashes.cc
index 11a7e479b..46cf0ba08 100644
--- a/apt-pkg/contrib/hashes.cc
+++ b/apt-pkg/contrib/hashes.cc
@@ -188,6 +188,13 @@ unsigned long long HashStringList::FileSize() const			/*{{{*/
    return strtoull(hv.c_str(), NULL, 10);
 }
 									/*}}}*/
+bool HashStringList::FileSize(unsigned long long const Size)		/*{{{*/
+{
+   std::string size;
+   strprintf(size, "%llu", Size);
+   return push_back(HashString("Checksum-FileSize", size));
+}
+									/*}}}*/
 bool HashStringList::supported(char const * const type)			/*{{{*/
 {
    for (char const * const * t = HashString::SupportedHashes(); *t != NULL; ++t)
@@ -361,9 +368,7 @@ APT_IGNORE_DEPRECATED_PUSH
    if ((d->CalcHashes & SHA512SUM) == SHA512SUM)
       hashes.push_back(HashString("SHA512", SHA512.Result().Value()));
 APT_IGNORE_DEPRECATED_POP
-   std::string SizeStr;
-   strprintf(SizeStr, "%llu", d->FileSize);
-   hashes.push_back(HashString("Checksum-FileSize", SizeStr));
+   hashes.FileSize(d->FileSize);
    return hashes;
 }
 APT_IGNORE_DEPRECATED_PUSH
diff --git a/apt-pkg/contrib/hashes.h b/apt-pkg/contrib/hashes.h
index 176ce4faa..e8d84da9e 100644
--- a/apt-pkg/contrib/hashes.h
+++ b/apt-pkg/contrib/hashes.h
@@ -96,6 +96,13 @@ class HashStringList
     */
    unsigned long long FileSize() const;
 
+   /** sets the filesize hash
+    *
+    * @param Size of the file
+    * @return @see #push_back
+    */
+   bool FileSize(unsigned long long const Size);
+
    /** check if the given hash type is supported
     *
     * @param type to check