Added support for each entry to remember: the file it came from, and

the beginning and ending character positions of that entry within the
file.  This makes it possible to reproduce the input exactly, with
only the changed entries updated.

journal.cc

@@ -165,7 +165,7 @@ void entry_t::add_transaction(transaction_t * xact)
 
 bool entry_t::valid() const
 {
-  if (! date)
+  if (! date || ! journal)
     return false;
 
   if (state != UNCLEARED && state != CLEARED && state != PENDING)
@@ -276,6 +276,7 @@ account_t * account_t::find_account(const std::string& name,
       return NULL;
 
     account = new account_t(this, first);
+    account->journal = journal;
 
     std::pair<accounts_map::iterator, bool> result
       = accounts.insert(accounts_pair(first, account));
@@ -338,7 +339,7 @@ std::ostream& operator<<(std::ostream& out, const account_t& account)
 
 bool account_t::valid() const
 {
-  if (depth > 256)
+  if (depth > 256 || ! journal)
     return false;
 
   for (accounts_map::const_iterator i = accounts.begin();
@@ -398,6 +399,7 @@ bool journal_t::add_entry(entry_t * entry)
     return false;
 
   entries.push_back(entry);
+  entry->journal = this;
 
   for (transactions_list::const_iterator i = entry->transactions.begin();
        i != entry->transactions.end();
@@ -422,6 +424,7 @@ bool journal_t::remove_entry(entry_t * entry)
     return false;
 
   entries.erase(i);
+  entry->journal = NULL;
 
   return true;
 }
@@ -686,6 +689,7 @@ void export_journal()
     .def(self == self)
     .def(self != self)
 
+    .def_readonly("journal", &account_t::journal)
     .add_property("parent",
 		  make_getter(&account_t::parent,
 			      return_internal_reference<1>()))
@@ -739,6 +743,11 @@ void export_journal()
     .def("__getitem__", transactions_getitem,
 	 return_internal_reference<1>())
 
+    .def_readonly("journal", &entry_base_t::journal)
+    .def_readonly("src_idx", &entry_base_t::src_idx)
+    .def_readonly("beg_pos", &entry_base_t::beg_pos)
+    .def_readonly("end_pos", &entry_base_t::end_pos)
+
     .def("add_transaction", py_add_transaction)
     .def("remove_transaction", &entry_base_t::remove_transaction)
 

journal.h

@@ -74,11 +74,17 @@ class transaction_t
   bool valid() const;
 };
 
+class journal_t;
+
 typedef std::list<transaction_t *> transactions_list;
 
 class entry_base_t
 {
  public:
+  journal_t *            journal;
+  unsigned long          src_idx;
+  std::istream::pos_type beg_pos;
+  std::istream::pos_type end_pos;
   transactions_list	 transactions;
 
   entry_base_t() {
@@ -216,6 +222,7 @@ class account_t
  public:
   typedef unsigned long ident_t;
 
+  journal_t *    journal;
   account_t *	 parent;
   std::string	 name;
   std::string	 note;
@@ -247,9 +254,11 @@ class account_t
 
   void add_account(account_t * acct) {
     accounts.insert(accounts_pair(acct->name, acct));
+    acct->journal = journal;
   }
   bool remove_account(account_t * acct) {
     accounts_map::size_type n = accounts.erase(acct->name);
+    acct->journal = NULL;
     return n > 0;
   }
 
@@ -325,6 +334,7 @@ class journal_t
   journal_t() {
     DEBUG_PRINT("ledger.memory.ctors", "ctor journal_t");
     master = new account_t(NULL, "");
+    master->journal = this;
     item_pool = item_pool_end = NULL;
   }
   ~journal_t();
@@ -338,9 +348,11 @@ class journal_t
 
   void add_account(account_t * acct) {
     master->add_account(acct);
+    acct->journal = this;
   }
   bool remove_account(account_t * acct) {
     return master->remove_account(acct);
+    acct->journal = NULL;
   }
 
   account_t * find_account(const std::string& name, bool auto_create = true) {
@@ -350,6 +362,7 @@ class journal_t
 
     account_t * account = master->find_account(name, auto_create);
     accounts_cache.insert(accounts_pair(name, account));
+    account->journal = this;
     return account;
   }
   account_t * find_account_re(const std::string& regexp);

textual.cc

@@ -7,6 +7,7 @@
 #include "config.h"
 #include "timing.h"
 #include "util.h"
+#include "acconf.h"
 #ifdef USE_BOOST_PYTHON
 #include "py_eval.h"
 #endif
@@ -308,6 +309,8 @@ unsigned int textual_parser_t::parse(std::istream&	 in,
 
   while (in.good() && ! in.eof()) {
     try {
+      std::istream::pos_type beg_pos = in.tellg();
+
       in.getline(line, MAX_LINE);
       if (in.eof())
 	break;
@@ -477,12 +480,16 @@ unsigned int textual_parser_t::parse(std::istream&	 in,
 
 	auto_entry_t * ae = new auto_entry_t(skip_ws(line + 1));
 	if (parse_transactions(in, account_stack.front(), *ae, "automated")) {
-	  if (ae->finalize())
+	  if (ae->finalize()) {
 	    journal->auto_entries.push_back(ae);
-	  else
+	    ae->src_idx = journal->sources.size() - 1;
+	    ae->beg_pos = beg_pos;
+	    ae->end_pos = in.tellg();
+	  } else {
 	    throw parse_error(path, linenum,
 			      "Automated entry failed to balance");
 	  }
+	}
 	break;
       }
 
@@ -496,6 +503,9 @@ unsigned int textual_parser_t::parse(std::istream&	 in,
 	  if (pe->finalize()) {
 	    extend_entry_base(journal, *pe);
 	    journal->period_entries.push_back(pe);
+	    pe->src_idx = journal->sources.size() - 1;
+	    pe->beg_pos = beg_pos;
+	    pe->end_pos = in.tellg();
 	  } else {
 	    throw parse_error(path, linenum, "Period entry failed to balance");
 	  }
@@ -543,9 +553,13 @@ unsigned int textual_parser_t::parse(std::istream&	 in,
 
       default: {
 	unsigned int first_line = linenum;
+
 	if (entry_t * entry = parse_entry(in, line, account_stack.front(),
 					  *this)) {
 	  if (journal->add_entry(entry)) {
+	    entry->src_idx = journal->sources.size() - 1;
+	    entry->beg_pos = beg_pos;
+	    entry->end_pos = in.tellg();
 	    count++;
 	  } else {
 	    delete entry;
@@ -584,6 +598,93 @@ unsigned int textual_parser_t::parse(std::istream&	 in,
   return count;
 }
 
+void write_textual_journal(journal_t& journal, std::string path,
+			   item_handler<transaction_t>& formatter,
+			   std::ostream& out)
+{
+  unsigned long index = 0;
+  std::string   found;
+  char          buf1[PATH_MAX];
+  char          buf2[PATH_MAX];
+
+#ifdef HAVE_REALPATH
+  realpath(path.c_str(), buf1);
+  for (strings_list::iterator i = journal.sources.begin();
+       i != journal.sources.end();
+       i++) {
+    realpath((*i).c_str(), buf2);
+    if (std::strcmp(buf1, buf2) == 0) {
+      found = *i;
+      break;
+    }
+    index++;
+  }
+#else
+  for (strings_list::iterator i = journal.sources.begin();
+       i != journal.sources.end();
+       i++) {
+    if (path == *i) {
+      found = *i;
+      break;
+    }
+    index++;
+  }
+#endif
+
+  if (found.empty())
+    throw error(std::string("Journal does not refer to file '") +
+		found + "'");
+
+  entries_list::iterator	  el = journal.entries.begin();
+  auto_entries_list::iterator	  al = journal.auto_entries.begin();
+  period_entries_list::iterator pl = journal.period_entries.begin();
+
+  std::istream::pos_type pos = 0;
+  std::istream::pos_type jump_to;
+
+  format_t hdr_fmt(config.write_hdr_format);
+
+  std::ifstream in(found.c_str());
+  while (! in.eof()) {
+    entry_base_t * base = NULL;
+    if (el != journal.entries.end() &&
+	pos == (*el)->beg_pos) {
+      hdr_fmt.format(out, details_t(**el));
+      base = *el++;
+    }
+    else if (al != journal.auto_entries.end() &&
+	     pos == (*al)->beg_pos) {
+      out << "= " << (*al)->predicate_string << '\n';
+      base = *al++;
+    }
+    else if (pl != journal.period_entries.end() &&
+	     pos == (*pl)->beg_pos) {
+      out << "~ " << (*pl)->period_string << '\n';
+      base = *pl++;
+    }
+
+    char c;
+    if (base) {
+      for (transactions_list::iterator x = base->transactions.begin();
+	   x != base->transactions.end();
+	   x++)
+	transaction_xdata(**x).dflags |= TRANSACTION_TO_DISPLAY;
+
+      walk_transactions(base->transactions, formatter);
+      formatter.flush();
+
+      while (pos < base->end_pos) {
+	in.get(c);
+	pos = in.tellg(); // pos++;
+      }
+    } else {
+      in.get(c);
+      pos = in.tellg(); // pos++;
+      out.put(c);
+    }
+  }
+}
+
 } // namespace ledger
 
 #ifdef USE_BOOST_PYTHON