Revert shared_ptr<io_data_t> changes until kinks are ironed out

https://github.com/fish-shell/fish-shell/pull/487

Revert "Merge branch 'oo-io' of git://github.com/xiaq/fish-shell into xiaq-oo-io"

This reverts commit f3c8f535a4, reversing
changes made to b02f6cf3bc.

Also reverts ac023f7588 and a79d3c680c

io.cpp

@@ -133,7 +133,7 @@ io_data_t *io_buffer_create(bool is_input)
     return buffer_redirect;
 }
 
-void io_buffer_destroy(const shared_ptr<io_data_t> &io_buffer)
+void io_buffer_destroy(io_data_t *io_buffer)
 {
 
     /**
@@ -151,9 +151,10 @@ void io_buffer_destroy(const shared_ptr<io_data_t> &io_buffer)
       Dont free fd for writing. This should already be free'd before
       calling exec_read_io_buffer on the buffer
     */
+    delete io_buffer;
 }
 
-void io_chain_t::remove(const shared_ptr<const io_data_t> &element)
+void io_chain_t::remove(const io_data_t *element)
 {
     // See if you can guess why std::find doesn't work here
     for (io_chain_t::iterator iter = this->begin(); iter != this->end(); ++iter)
@@ -166,22 +167,48 @@ void io_chain_t::remove(const shared_ptr<const io_data_t> &element)
     }
 }
 
+io_chain_t io_chain_t::duplicate() const
+{
+    io_chain_t result;
+    result.reserve(this->size());
+    for (io_chain_t::const_iterator iter = this->begin(); iter != this->end(); iter++)
+    {
+        const io_data_t *io = *iter;
+        result.push_back(new io_data_t(*io));
+    }
+    return result;
+}
+
 void io_chain_t::duplicate_prepend(const io_chain_t &src)
 {
-    /* Prepend a duplicate of src before this. */
-    this->insert(this->begin(), src.begin(), src.end());
+    /* Prepend a duplicate of src before this. Start by inserting a bunch of NULLs (so we only have to reallocate once) and then replace them. */
+    this->insert(this->begin(), src.size(), NULL);
+    for (size_t idx = 0; idx < src.size(); idx++)
+    {
+        const io_data_t *src_data = src.at(idx);
+        this->at(idx) = new io_data_t(*src_data);
+    }
 }
 
 void io_chain_t::destroy()
 {
+    for (size_t idx = 0; idx < this->size(); idx++)
+    {
+        delete this->at(idx);
+    }
     this->clear();
 }
 
-void io_remove(io_chain_t &list, const shared_ptr<const io_data_t> &element)
+void io_remove(io_chain_t &list, const io_data_t *element)
 {
     list.remove(element);
 }
 
+io_chain_t io_duplicate(const io_chain_t &chain)
+{
+    return chain.duplicate();
+}
+
 void io_print(const io_chain_t &chain)
 {
     if (chain.empty())
@@ -193,7 +220,7 @@ void io_print(const io_chain_t &chain)
     fprintf(stderr, "Chain %p (%ld items):\n", &chain, (long)chain.size());
     for (size_t i=0; i < chain.size(); i++)
     {
-        const shared_ptr<const io_data_t> &io = chain.at(i);
+        const io_data_t *io = chain.at(i);
         fprintf(stderr, "\t%lu: fd:%d, input:%s, ", (unsigned long)i, io->fd, io->is_input ? "yes" : "no");
         switch (io->io_mode)
         {
@@ -227,51 +254,50 @@ void io_chain_destroy(io_chain_t &chain)
 }
 
 /* Return the last IO for the given fd */
-shared_ptr<const io_data_t> io_chain_t::get_io_for_fd(int fd) const
+const io_data_t *io_chain_t::get_io_for_fd(int fd) const
 {
     size_t idx = this->size();
     while (idx--)
     {
-        const shared_ptr<const io_data_t> &data = this->at(idx);
+        const io_data_t *data = this->at(idx);
         if (data->fd == fd)
         {
             return data;
         }
     }
-    return shared_ptr<const io_data_t>();
+    return NULL;
 }
 
-shared_ptr<io_data_t> io_chain_t::get_io_for_fd(int fd)
+io_data_t *io_chain_t::get_io_for_fd(int fd)
 {
     size_t idx = this->size();
     while (idx--)
     {
-        const shared_ptr<io_data_t> &data = this->at(idx);
+        io_data_t *data = this->at(idx);
         if (data->fd == fd)
         {
             return data;
         }
     }
-    return shared_ptr<io_data_t>();
+    return NULL;
 }
 
 /* The old function returned the last match, so we mimic that. */
-shared_ptr<const io_data_t> io_chain_get(const io_chain_t &src, int fd)
+const io_data_t *io_chain_get(const io_chain_t &src, int fd)
 {
     return src.get_io_for_fd(fd);
 }
 
-shared_ptr<io_data_t> io_chain_get(io_chain_t &src, int fd)
+io_data_t *io_chain_get(io_chain_t &src, int fd)
 {
     return src.get_io_for_fd(fd);
 }
 
-io_chain_t::io_chain_t(const shared_ptr<io_data_t> &data) :
-    std::vector<shared_ptr<io_data_t> >(1, data)
+io_chain_t::io_chain_t(io_data_t *data) : std::vector<io_data_t *>(1, data)
 {
 
 }
 
-io_chain_t::io_chain_t() : std::vector<shared_ptr<io_data_t> >()
+io_chain_t::io_chain_t() : std::vector<io_data_t *>()
 {
 }