X-Git-Url: https://git.creatis.insa-lyon.fr/pubgit/?a=blobdiff_plain;f=src%2Fjdatasrc.cxx;h=cfb526abd8593898d18c825923ecb1f799227669;hb=224876ca6cbe71952f2a1d66d9853eca7745d3a0;hp=e6c644307dd4b8840ba28903a23c4637b90cef67;hpb=fea9426f960497d2d9124ab532d2097f2915678f;p=gdcm.git

diff --git a/src/jdatasrc.cxx b/src/jdatasrc.cxx
index e6c64430..cfb526ab 100644
--- a/src/jdatasrc.cxx
+++ b/src/jdatasrc.cxx
@@ -1,5 +1,5 @@
 /*
- * jdatasrc.c
+ * jdatasrc.cxx
  *
  * Copyright (C) 1994-1996, Thomas G. Lane.
  * This file is part of the Independent JPEG Group's software.
@@ -18,12 +18,21 @@
 
 /* Expanded data source object for stdio input */
 
+extern "C" {
+  typedef  boolean(*boolean_jpeg_decompress_struct)(jpeg_decompress_struct*);
+  typedef  void(*void_jpeg_decompress_struct)(jpeg_decompress_struct*);
+  typedef  void(*void_jpeg_decompress_struct_long)(jpeg_decompress_struct*,long);
+}
+
 typedef struct {
   struct jpeg_source_mgr pub;  /* public fields */
 
-  std::ifstream *infile;  /* source stream */ 
+  std::istream *infile;  /* source stream */ 
   JOCTET * buffer;        /* start of buffer */
   boolean start_of_file;  /* have we gotten any data yet? */
+
+  GDCM_NAME_SPACE::JPEGFragment *frag;
+  size_t bytes_read;
 } my_source_mgr;
 
 typedef my_source_mgr * my_src_ptr;
@@ -87,7 +96,19 @@ fill_input_buffer (j_decompress_ptr cinfo)
 {
   my_src_ptr src = (my_src_ptr) cinfo->src;
 
-  src->infile->read( (char*)src->buffer, INPUT_BUF_SIZE);
+  if( src->bytes_read == src->frag->GetLength() )
+    {
+    // Start the I/O suspension simply by returning false here:
+    return FALSE;
+    }
+
+  size_t input_buf_size = INPUT_BUF_SIZE;
+  if( (src->bytes_read + INPUT_BUF_SIZE) > src->frag->GetLength() )
+    {
+    input_buf_size = src->frag->GetLength() - src->bytes_read;
+    }
+
+  src->infile->read( (char*)src->buffer, input_buf_size);
   size_t nbytes = src->infile->gcount();
 
   if (nbytes <= 0) {
@@ -103,6 +124,7 @@ fill_input_buffer (j_decompress_ptr cinfo)
   src->pub.next_input_byte = src->buffer;
   src->pub.bytes_in_buffer = nbytes;
   src->start_of_file = FALSE;
+  src->bytes_read += nbytes;
 
   return TRUE;
 }
@@ -176,7 +198,7 @@ term_source (j_decompress_ptr cinfo)
  */
 
 GLOBAL(void)
-jpeg_stdio_src (j_decompress_ptr cinfo, std::ifstream * infile)
+jpeg_stdio_src (j_decompress_ptr cinfo, std::istream * infile, GDCM_NAME_SPACE::JPEGFragment *frag, int flag)
 {
   my_src_ptr src;
 
@@ -198,12 +220,20 @@ jpeg_stdio_src (j_decompress_ptr cinfo, std::ifstream * infile)
   }
 
   src = (my_src_ptr) cinfo->src;
-  src->pub.init_source = init_source;
-  src->pub.fill_input_buffer = fill_input_buffer;
-  src->pub.skip_input_data = skip_input_data;
+  src->pub.init_source = reinterpret_cast<void_jpeg_decompress_struct>(init_source);
+  src->pub.fill_input_buffer = reinterpret_cast<boolean_jpeg_decompress_struct>(fill_input_buffer);
+  src->pub.skip_input_data = reinterpret_cast<void_jpeg_decompress_struct_long>(skip_input_data);
   src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */
-  src->pub.term_source = term_source;
+  src->pub.term_source = reinterpret_cast<void_jpeg_decompress_struct>(term_source);
   src->infile = infile;
-  src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
-  src->pub.next_input_byte = NULL; /* until buffer loaded */
+  
+  // Need to setup a new buffer, clean bytes_in_buffer and next_input_byte
+  if( flag )
+    {
+    src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
+    src->pub.next_input_byte = NULL; /* until buffer loaded */
+    }
+  //only upate the new fragment, valid for both 'flag' value
+  src->frag = frag;
+  src->bytes_read = 0;
 }