Add support for hash chaining to detect modifications in postings

The following details of a posting contribute to its hash:

  fullname of account
  string representation of amount

Each posting hashes contributes to the transaction hash, which is compromised
of:

  previous transaction’s hash (as encountered in parsing order)
  actual date
  optional auxiliary date
  optional code
  payee
  hashes of all postings

Note that this means that changes in the “code” or any of the comments

1 files changed, 2 insertions, 2 deletions

diff --git a/src/journal.cc b/src/journal.cc
index a6559e3d..b5ae3f1b 100644
--- a/src/journal.cc
+++ b/src/journal.cc
@@ -466,7 +466,7 @@ bool journal_t::remove_xact(xact_t * xact)
   return true;
 }
 
-std::size_t journal_t::read(parse_context_stack_t& context)
+std::size_t journal_t::read(parse_context_stack_t& context, bool store_hashes)
 {
   std::size_t count = 0;
   try {
@@ -485,7 +485,7 @@ std::size_t journal_t::read(parse_context_stack_t& context)
     if (! current.master)
       current.master = master;
 
-    count = read_textual(context);
+    count = read_textual(context, store_hashes);
     if (count > 0) {
       if (! current.pathname.empty())
         sources.push_back(fileinfo_t(current.pathname));