[beast: 11/13] BSE: move Bse.collect_stats methods into bseapi.idl and fix offset guard

[Tim Janik <timj src gnome org>]

commit 80b29b1b8cce5df5612e4d9cd41acd9d36e40d17
Author: Tim Janik <timj gnu org>
Date:   Fri Sep 1 00:58:24 2017 +0200

    BSE: move Bse.collect_stats methods into bseapi.idl and fix offset guard
    
    Signed-off-by: Tim Janik <timj gnu org>

 bse/Makefile.am            |    1 -
 bse/bseapi.idl             |    2 +-
 bse/bseeditablesample.cc   |   49 ++++++++++++++++++++++++
 bse/bseeditablesample.hh   |   15 ++++---
 bse/bseeditablesample.proc |   90 --------------------------------------------
 5 files changed, 58 insertions(+), 99 deletions(-)
---
diff --git a/bse/Makefile.am b/bse/Makefile.am
index 57fe7cc..fed5ad8 100644
--- a/bse/Makefile.am
+++ b/bse/Makefile.am
@@ -113,7 +113,6 @@ idl_dummy_files = $(strip   \
 )
 # BSE procedure sources
 bse_proc_sources = $(strip \
-       bseeditablesample.proc  \
        bsejanitor.proc         \
                                                                                bsesource.proc          \
                                bseitem.proc                                    \
diff --git a/bse/bseapi.idl b/bse/bseapi.idl
index 721b8fc..942ee39 100644
--- a/bse/bseapi.idl
+++ b/bse/bseapi.idl
@@ -817,7 +817,7 @@ interface EditableSample : Item {
    * @param max-pairs     Maximum number of (min, max) pairs to collect
    * @return              Block of samples
    */
-  //FloatSeq    collect_stats  (int64 voffset, float64 offset_scale, int64 block_size, int64 stepping, int64 
max_pairs);
+  FloatSeq    collect_stats  (int64 voffset, float64 offset_scale, int64 block_size, int64 stepping, int64 
max_pairs);
   void        close          (); ///< Close an opened sample.
   int64       get_length     (); ///< Return the number of values in the sample.
   int64       get_n_channels (); ///< Return the number of channels in the sample.
diff --git a/bse/bseeditablesample.cc b/bse/bseeditablesample.cc
index 6235a58..ccc68af 100644
--- a/bse/bseeditablesample.cc
+++ b/bse/bseeditablesample.cc
@@ -238,4 +238,53 @@ EditableSampleImpl::open ()
   return error;
 }
 
+FloatSeq
+EditableSampleImpl::collect_stats (int64 voffset, double offset_scale, int64 block_size, int64 stepping, 
int64 max_pairs)
+{
+  BseEditableSample *self = as<BseEditableSample*>();
+  GslDataCache *dcache = NULL;
+  if (BSE_EDITABLE_SAMPLE_OPENED (self) && self->wchunk)
+    dcache = self->wchunk->dcache;
+  FloatSeq floats;
+  floats.resize (max_pairs * 2, 0);
+  const ssize_t dhandle_length = gsl_data_handle_length (dcache->dhandle);
+  if (stepping < 1 || !dcache || voffset + block_size > dhandle_length)
+    return floats;
+  GslDataCacheNode *dnode = gsl_data_cache_ref_node (dcache, voffset, GSL_DATA_CACHE_DEMAND_LOAD);
+  ssize_t j, dnode_length = dcache->node_size;
+  for (j = 0; j < max_pairs; j++)
+    {
+      ssize_t i, cur_offset = j * offset_scale;
+      float min = +1, max = -1;
+      // keep alignment across offset scaling
+      cur_offset /= stepping;
+      cur_offset = voffset + cur_offset * stepping;
+      // collect stats for one block
+      for (i = cur_offset; i < cur_offset + block_size; i += stepping)
+        {
+          size_t pos;
+          if (i < dnode->offset || i >= dnode->offset + dnode_length)
+            {
+              gsl_data_cache_unref_node (dcache, dnode);
+              if (i >= dhandle_length)
+                dnode = NULL;
+              else
+                dnode = gsl_data_cache_ref_node (dcache, i, // demand_load the first block (j==0)
+                                                 j == 0 ? GSL_DATA_CACHE_DEMAND_LOAD : GSL_DATA_CACHE_PEEK);
+              if (!dnode)
+                goto break_loops;
+            }
+          pos = i - dnode->offset;
+          min = MIN (min, dnode->data[pos]);
+          max = MAX (max, dnode->data[pos]);
+        }
+      floats[j * 2] = min;
+      floats[j * 2 + 1] = max;
+    }
+  gsl_data_cache_unref_node (dcache, dnode);
+ break_loops:
+  floats.resize (j * 2);
+  return floats;
+}
+
 } // Bse
diff --git a/bse/bseeditablesample.hh b/bse/bseeditablesample.hh
index 28c76f4..94d6e05 100644
--- a/bse/bseeditablesample.hh
+++ b/bse/bseeditablesample.hh
@@ -30,14 +30,15 @@ namespace Bse {
 
 class EditableSampleImpl : public ItemImpl, public virtual EditableSampleIface {
 protected:
-  virtual       ~EditableSampleImpl ();
+  virtual          ~EditableSampleImpl ();
 public:
-  explicit       EditableSampleImpl (BseObject*);
-  virtual void   close              () override;
-  virtual int64  get_length         () override;
-  virtual int64  get_n_channels     () override;
-  virtual double get_osc_freq       () override;
-  virtual Error  open               () override;
+  explicit         EditableSampleImpl  (BseObject*);
+  virtual FloatSeq collect_stats       (int64 voffset, double offset_scale, int64 block_size, int64 
stepping, int64 max_pairs) override;
+  virtual void     close               () override;
+  virtual int64    get_length          () override;
+  virtual int64    get_n_channels      () override;
+  virtual double   get_osc_freq        () override;
+  virtual Error    open                () override;
 };
 
 } // Bse