cmMidiFile.h/c : Added cmMidiFileInsertMsg() Also rearranged code to isolate

cmMidiTrackMsg_t allocation.  These changes are not yet tested.

cmMidiFile.c

@@ -19,8 +19,6 @@
 #define mfSwap32(v)  cmSwap32(v)
 #endif
 
-
-
 typedef struct
 {
   unsigned          cnt;   // count of track records
@@ -160,10 +158,25 @@ cmMfRC_t _cmMidiFileReadVarLen( _cmMidiFile_t* mfp, unsigned* p )
   return kOkMfRC; 
 }
 
-cmMfRC_t _cmMidiFileAppendTrackMsg( _cmMidiFile_t* mfp, unsigned short trkIdx, unsigned dtick, cmMidiByte_t status, cmMidiTrackMsg_t** trkMsgPtrPtr )
+cmMidiTrackMsg_t* _cmMidiFileAllocMsg( _cmMidiFile_t* mfp, unsigned short trkIdx, unsigned dtick, cmMidiByte_t status )
 {
   cmMidiTrackMsg_t* tmp = (cmMidiTrackMsg_t*)_cmMidiFileMalloc(mfp, sizeof(cmMidiTrackMsg_t) );
 
+  // set the generic track record fields
+  tmp->dtick     = dtick;
+  tmp->status   = status;
+  tmp->metaId   = kInvalidMetaMdId;
+  tmp->trkIdx   = trkIdx;
+  tmp->byteCnt  = 0;
+  tmp->uid      = mfp->nextUid++;
+
+  return tmp;
+}
+
+cmMfRC_t _cmMidiFileAppendTrackMsg( _cmMidiFile_t* mfp, unsigned short trkIdx, unsigned dtick, cmMidiByte_t status, cmMidiTrackMsg_t** trkMsgPtrPtr )
+{
+  cmMidiTrackMsg_t* tmp = _cmMidiFileAllocMsg( mfp, trkIdx, dtick, status );
+    
   // link new record onto track record chain
   if( mfp->trkV[trkIdx].base == NULL )
     mfp->trkV[trkIdx].base = tmp;
@@ -174,12 +187,6 @@ cmMfRC_t _cmMidiFileAppendTrackMsg( _cmMidiFile_t* mfp, unsigned short trkIdx, u
   mfp->trkV[trkIdx].cnt++;
 
 
-  // set the generic track record fields
-  tmp->dtick     = dtick;
-  tmp->status   = status;
-  tmp->metaId   = kInvalidMetaMdId;
-  tmp->trkIdx   = trkIdx;
-  tmp->byteCnt  = 0;
   *trkMsgPtrPtr = tmp;
 
   return kOkMfRC;
@@ -521,6 +528,43 @@ cmMfRC_t _cmMidiFileClose( _cmMidiFile_t* mfp )
   
 }
 
+void _cmMidiFileLinearize( _cmMidiFile_t* mfp )
+{
+  unsigned trkIdx,i,j;
+  
+  // get the total trk msg count
+  mfp->msgN = 0;
+  for(trkIdx=0; trkIdx<mfp->trkN; ++trkIdx)
+    mfp->msgN += mfp->trkV[ trkIdx ].cnt;
+
+  // allocate the trk msg index vector: msgV[]
+  mfp->msgV = cmMemResizeZ(cmMidiTrackMsg_t*, mfp->msgV, mfp->msgN);
+
+  // store a pointer to every trk msg in msgV[]
+  for(i=0,j=0; i<mfp->trkN; ++i)
+  {
+    cmMidiTrackMsg_t* m = mfp->trkV[i].base;
+    
+    for(; m!=NULL; m=m->link)
+    {
+      assert( j < mfp->msgN );
+      
+      mfp->msgV[j++] = m;
+    }
+  }
+
+
+  // set the atick value in each msg
+  _cmMidiFileSetAccumulateTicks(mfp);
+    
+  // sort msgV[] in ascending order on atick
+  qsort( mfp->msgV, mfp->msgN, sizeof(cmMidiTrackMsg_t*), _cmMidiFileSortFunc );
+
+  // set the amicro value in each msg
+  _cmMidiFileSetAbsoluteTime(mfp);
+  
+}
+
 
 cmMfRC_t cmMidiFileOpen( cmCtx_t* ctx, cmMidiFileH_t* hPtr, const char* fn )
 {
@@ -528,7 +572,6 @@ cmMfRC_t cmMidiFileOpen( cmCtx_t* ctx, cmMidiFileH_t* hPtr, const char* fn )
   _cmMidiFile_t* mfp    = NULL;
   unsigned short trkIdx = 0;
   cmErr_t        err;
-  unsigned i,j;
 
   if( cmMidiFileIsValid(*hPtr) )
     if((rc = _cmMidiFileClose(_cmMidiFileHandleToPtr(*hPtr))) != kOkMfRC )
@@ -591,43 +634,12 @@ cmMfRC_t cmMidiFileOpen( cmCtx_t* ctx, cmMidiFileH_t* hPtr, const char* fn )
     }
   }
 
-  // get the total trk msg count
+  // store the file name
-  mfp->msgN = 0;
-  for(trkIdx=0; trkIdx<mfp->trkN; ++trkIdx)
-    mfp->msgN += mfp->trkV[ trkIdx ].cnt;
-
-  // allocate the trk msg index vector: msgV[]
-  mfp->msgV = cmMemAllocZ(cmMidiTrackMsg_t*, mfp->msgN);
-
-  mfp->nextUid = 0;
-
-  // store a pointer to every trk msg in msgV[]  and set 'uid'  
-  for(i=0,j=0; i<mfp->trkN; ++i)
-  {
-    cmMidiTrackMsg_t* m = mfp->trkV[i].base;
-    
-    for(; m!=NULL; m=m->link)
-    {
-      assert( j < mfp->msgN );
-      
-      mfp->msgV[j++] = m;
-      m->uid         = mfp->nextUid++;
-    }
-  }
-
   mfp->fn          = _cmMidiFileMalloc(mfp,strlen(fn)+1);
   assert( mfp->fn != NULL );
   strcpy(mfp->fn,fn);
   
-
+  _cmMidiFileLinearize(mfp);
-  // set the atick value in each msg
-  _cmMidiFileSetAccumulateTicks(mfp);
-    
-  // sort msgV[] in ascending order on atick
-  qsort( mfp->msgV, mfp->msgN, sizeof(cmMidiTrackMsg_t*), _cmMidiFileSortFunc );
-
-  // set the amicro value in each msg
-  _cmMidiFileSetAbsoluteTime(mfp);
   
   hPtr->h = mfp;
 
@@ -1141,6 +1153,103 @@ cmMfRC_t cmMidiFileSetVelocity( cmMidiFileH_t h, unsigned uid, cmMidiByte_t vel
   return kOkMfRC;
 }
 
+// Returns NULL if uid is not found or if it the first msg on the track.
+cmMidiTrackMsg_t*  _cmMidiFileMsgBeforeUid( _cmMidiFile_t* p, unsigned uid )
+{
+  cmMidiTrackMsg_t* m;
+  
+  if((m = _cmMidiFileUidToMsg(p,uid)) == NULL )
+    return NULL;
+
+  assert( m->trkIdx < p->trkN );
+
+  cmMidiTrackMsg_t* m0 = NULL;
+  cmMidiTrackMsg_t* m1 = p->trkV[ m->trkIdx ].base;
+  for(; m1!=NULL; m1 = m1->link)
+  {
+    if( m1->uid == uid )
+      break;
+    m0 = m1;
+  }
+
+  return m0;
+}
+
+unsigned _cmMidiFileIsMsgFirstOnTrack( _cmMidiFile_t* p, unsigned uid )
+{
+  unsigned i;
+  for(i=0; i<p->trkN; ++i)
+    if( p->trkV[i].base!=NULL && p->trkV[i].base->uid == uid )
+      return i;
+  
+  return cmInvalidIdx;   
+}
+
+
+cmMfRC_t cmMidiFileInsertMsg( cmMidiFileH_t h, unsigned uid, int dtick, cmMidiByte_t ch, cmMidiByte_t status, cmMidiByte_t d0, cmMidiByte_t d1 )
+{
+  _cmMidiFile_t*    mfp    = _cmMidiFileHandleToPtr(h);
+  assert( mfp != NULL );
+  cmMidiTrackMsg_t* ref    = NULL;
+  unsigned          trkIdx = cmInvalidIdx;
+
+  // if dtick is positive ...
+  if( dtick >= 0 )
+  {
+    ref    = _cmMidiFileUidToMsg(mfp,uid); // ... then get the ref. msg.
+    trkIdx = ref->trkIdx;
+  }
+  else // if dtick is negative ...
+  {
+    // ... get get the msg before the ref. msg.
+    if((ref = _cmMidiFileMsgBeforeUid(mfp,uid)) == NULL )
+    {
+      // ... the ref. msg was first in the track so there is no msg before it
+      trkIdx = _cmMidiFileIsMsgFirstOnTrack(mfp,uid);
+    }
+  }
+
+  // verify that the reference msg was found
+  if( trkIdx == cmInvalidIdx )
+    return cmErrMsg(&mfp->err,kUidNotFoundMfRC,"The UID (%i) reference note could not be located.",uid);
+
+  assert( trkIdx < mfp->trkN );
+
+  // complete the msg setup
+  _cmMidiTrack_t* trk   = mfp->trkV + trkIdx;
+  cmMidiTrackMsg_t* m   = _cmMidiFileAllocMsg(mfp, trkIdx, abs(dtick), status );
+  cmMidiChMsg_t*    c   = (cmMidiChMsg_t*)m->u.chMsgPtr; // cast away const
+  c->ch   = ch;
+  c->d0   = d0;
+  c->d1   = d1;
+
+  // if 'm' is prior to the first msg in the track
+  if( ref == NULL )
+  {
+    // ... then make 'm' the first msg in the first msg
+    m->link = trk->base;
+    trk->base = m;
+    // 'm' is before ref and the track cannot be empty (because ref is in it) 'm'
+    // can never be the last msg in the list
+  } 
+  else // ref is the msg before 'm'
+  {
+    m->link   = ref->link;
+    ref->link = m;
+    
+    // if ref was the last msg in the trk ...
+    if( trk->last == ref )
+      trk->last = m;  //... then 'm' is now the last msg in the trk
+  }
+
+  trk->cnt += 1;
+
+  _cmMidiFileLinearize(mfp);
+
+  return kOkMfRC;
+
+}
+
 unsigned  cmMidiFileSeekUsecs( cmMidiFileH_t h, unsigned long long offsUSecs, unsigned* msgUsecsPtr, unsigned* microsPerTickPtr )
 {
   _cmMidiFile_t* p;

cmMidiFile.h

@@ -161,6 +161,10 @@ extern "C" {
   // Set the velocity of a note-on/off msg identified by 'uid'.
   cmMfRC_t             cmMidiFileSetVelocity( cmMidiFileH_t h, unsigned uid, cmMidiByte_t vel );
 
+  // Insert a MIDI message relative to the reference msg identified by 'uid'.
+  // If dtick is positive/negative then the new msg is inserted after/before the reference msg.  
+  cmMfRC_t             cmMidiFileInsertMsg( cmMidiFileH_t h, unsigned uid, int dtick, cmMidiByte_t ch, cmMidiByte_t status, cmMidiByte_t d0, cmMidiByte_t d1 );
+  
   // Return a pointer to the first msg at or after 'usecsOffs' or kInvalidIdx if no
   // msg exists after 'usecsOffs'.  Note that 'usecOffs' is an offset from the beginning
   // of the file.