commit 6451ed7b8b7c40de68d7deb84a0f26544594fc7c
Author: Joey Hess <joey@kitenet.net>
Date:   Wed Oct 20 18:18:26 2010 -0400

    patch2, hand-applied

diff --git a/src/repository.cpp b/src/repository.cpp
index b7faaa7..a0e5f4c 100644
--- a/src/repository.cpp
+++ b/src/repository.cpp
@@ -51,7 +51,7 @@ public:
 static ProcessCache processCache;
 
 Repository::Repository(const Rules::Repository &rule)
-    : name(rule.name), commitCount(0), outstandingTransactions(0), processHasStarted(false)
+    : name(rule.name), commitCount(0), outstandingTransactions(0), lastrevmark(0), processHasStarted(false)
 {
     foreach (Rules::Repository::Branch branchRule, rule.branches) {
         Branch branch;
@@ -108,8 +108,8 @@ void Repository::reloadBranches()
     }
 }
 
-void Repository::createBranch(const QString &branch, int revnum,
-                              const QString &branchFrom, int)
+int Repository::createBranch(const QString &branch, int revnum,
+                              const QString &branchFrom, int origrev)
 {
     startFastImport();
     if (!branches.contains(branch)) {
@@ -122,7 +122,10 @@ void Repository::createBranch(const QString &branch, int revnum,
         branchRef.prepend("refs/heads/");
 
     Branch &br = branches[branch];
-    if (br.created && br.created != revnum) {
+    /* avoid rewinding master, this crashes if master exists but all
+     * commits so far have gone to a branch and the branch is then copied
+     * to master. JEH */
+    if (br.created && br.created != revnum && ! branch.startsWith("master")) {
         QByteArray backupBranch = branchRef + '_' + QByteArray::number(revnum);
         qWarning() << branch << "already exists; backing up to" << backupBranch;
 
@@ -138,13 +141,21 @@ void Repository::createBranch(const QString &branch, int revnum,
     if (!branches.contains(branchFrom) || !branches.value(branchFrom).created) {
         qCritical() << branch << "in repository" << name
                     << "is branching from branch" << branchFrom
-                    << "but the latter doesn't exist. Can't continue.";
-        exit(1);
+                    << "but the latter doesn't exist. Falling back to copy.";
+        return 0;
     }
 
-    fastImport.write("reset " + branchRef + "\nfrom " + branchFromRef + "\n\n"
-                     "progress Branch " + branchRef + " created from "
-                     + branchFromRef + " r" + QByteArray::number(revnum) + "\n\n");
+    if (origrev == revnum - 1 || rev2mark[origrev] == 0) {
+      fastImport.write("reset " + branchRef + "\nfrom " + branchFromRef + "\n\n"
+                       "progress Branch " + branchRef + " created from plain branch "
+                       + branchFromRef + " r" + QByteArray::number(revnum) + "\n\n");
+    }
+    else {
+       fastImport.write("reset " + branchRef + "\nfrom :1000" + QByteArray::number(rev2mark[origrev]) + "\n\n"
+                     "progress Branch " + branchRef + " created from mark "
+                     + branchFromRef + " r" + QByteArray::number(origrev) + "\n\n");
+    }
+    return 1;
 }
 
 Repository::Transaction *Repository::newTransaction(const QString &branch, const QString &svnprefix,
@@ -318,6 +329,7 @@ QIODevice *Repository::Transaction::addFile(const QString &path, int mode, qint6
 
 void Repository::Transaction::commit()
 {
+	int i;
     processCache.touch(repository);
 
     // create the commit message
@@ -334,6 +346,18 @@ void Repository::Transaction::commit()
 
         QTextStream s(&repository->fastImport);
         s << "commit " << branchRef << endl;
+	
+	for (i=repository->lastrevmark+1;i<revnum; i++) {
+		repository->rev2mark[i]=repository->lastrevmark;
+	}
+	if (repository->lastrevmark+1 != revnum -1)
+		printf("debug: added rev2marks %i..%i = %i\n", repository->lastrevmark+1, revnum-1, repository->lastrevmark);
+	repository->lastrevmark=revnum;
+	
+	repository->rev2mark[revnum]=revnum;
+	s << "mark :1000" << revnum << endl;
+	printf("debug: added mark for %i\n", revnum);
+
         s << "committer " << QString::fromUtf8(author) << ' ' << datetime << " -0000" << endl;
 
         Branch &br = repository->branches[branch];
diff --git a/src/repository.h b/src/repository.h
index ad23559..61fb09d 100644
--- a/src/repository.h
+++ b/src/repository.h
@@ -58,7 +58,7 @@ public:
     ~Repository();
 
     void reloadBranches();
-    void createBranch(const QString &branch, int revnum,
+    int createBranch(const QString &branch, int revnum,
                       const QString &branchFrom, int revFrom);
     Transaction *newTransaction(const QString &branch, const QString &svnprefix, int revnum);
 
@@ -84,11 +84,13 @@ private:
 
     QHash<QString, Branch> branches;
     QHash<QString, AnnotatedTag> annotatedTags;
+    QHash<int, int> rev2mark;
     QString name;
     QProcess fastImport;
     int commitCount;
     int outstandingTransactions;
     int lastmark;
+    int lastrevmark;
     bool processHasStarted;
 
     void startFastImport();
diff --git a/src/svn.cpp b/src/svn.cpp
index 04cf6bf..916a38a 100644
--- a/src/svn.cpp
+++ b/src/svn.cpp
@@ -600,7 +600,7 @@ int SvnRevision::exportInternal(const char *key, const svn_fs_path_change_t *cha
                          << "is an SVN rename from"
                          << qPrintable(previous) << "rev" << rev_from;
                 return EXIT_SUCCESS;
-            } else if (0) { /* XXX HACH REMOVE JEH */
+            } else {
                 // same repository but not same branch
                 // this means this is a plain branch
                 qDebug() << qPrintable(repository) << ": branch"
@@ -615,14 +615,15 @@ int SvnRevision::exportInternal(const char *key, const svn_fs_path_change_t *cha
                     return EXIT_FAILURE;
                 }
 
-                repo->createBranch(branch, revnum, prevbranch, rev_from);
-                if (rule.annotate) {
-                    // create an annotated tag
-                    fetchRevProps();
-                    repo->createAnnotatedTag(branch, svnprefix, revnum, authorident,
+                if (repo->createBranch(branch, revnum, prevbranch, rev_from)) {
+                	if (rule.annotate) {
+                    		// create an annotated tag
+                    		fetchRevProps();
+                    		repo->createAnnotatedTag(branch, svnprefix, revnum, authorident,
                                              epoch, log);
-                }
-                return EXIT_SUCCESS;
+                	}
+                	return EXIT_SUCCESS;
+		}
             }
         }
     }