Update libjpeg-turbo to r722.

jdmainct.c

 /*
  * jdmainct.c
  *
  * Copyright (C) 1994-1996, Thomas G. Lane.
  * Copyright (C) 2010, D. R. Commander.
  * This file is part of the Independent JPEG Group's software.
  * For conditions of distribution and use, see the accompanying README file.
  *
  * This file contains the main buffer controller for decompression.
  * The main buffer lies between the JPEG decompressor proper and the
@@ skipping 143 matching lines @@
              JDIMENSION *out_row_ctr, JDIMENSION out_rows_avail));
 #endif
 
 
 LOCAL(void)
 alloc_funny_pointers (j_decompress_ptr cinfo)
 /* Allocate space for the funny pointer lists.
  * This is done only once, not once per pass.
  */
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
   int ci, rgroup;
   int M = cinfo->_min_DCT_scaled_size;
   jpeg_component_info *compptr;
   JSAMPARRAY xbuf;
 
   /* Get top-level space for component array pointers.
    * We alloc both arrays with one call to save a few cycles.
    */
-  main->xbuffer[0] = (JSAMPIMAGE)
+  main_ptr->xbuffer[0] = (JSAMPIMAGE)
     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                 cinfo->num_components * 2 * SIZEOF(JSAMPARRAY));
-  main->xbuffer[1] = main->xbuffer[0] + cinfo->num_components;
+  main_ptr->xbuffer[1] = main_ptr->xbuffer[0] + cinfo->num_components;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) /
       cinfo->_min_DCT_scaled_size; /* height of a row group of component */
     /* Get space for pointer lists --- M+4 row groups in each list.
      * We alloc both pointer lists with one call to save a few cycles.
      */
     xbuf = (JSAMPARRAY)
       (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                   2 * (rgroup * (M + 4)) * SIZEOF(JSAMPROW));
     xbuf += rgroup;             /* want one row group at negative offsets */
-    main->xbuffer[0][ci] = xbuf;
+    main_ptr->xbuffer[0][ci] = xbuf;
     xbuf += rgroup * (M + 4);
-    main->xbuffer[1][ci] = xbuf;
+    main_ptr->xbuffer[1][ci] = xbuf;
   }
 }
 
 
 LOCAL(void)
 make_funny_pointers (j_decompress_ptr cinfo)
 /* Create the funny pointer lists discussed in the comments above.
- * The actual workspace is already allocated (in main->buffer),
+ * The actual workspace is already allocated (in main_ptr->buffer),
  * and the space for the pointer lists is allocated too.
  * This routine just fills in the curiously ordered lists.
  * This will be repeated at the beginning of each pass.
  */
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
   int ci, i, rgroup;
   int M = cinfo->_min_DCT_scaled_size;
   jpeg_component_info *compptr;
   JSAMPARRAY buf, xbuf0, xbuf1;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) /
       cinfo->_min_DCT_scaled_size; /* height of a row group of component */
-    xbuf0 = main->xbuffer[0][ci];
-    xbuf1 = main->xbuffer[1][ci];
+    xbuf0 = main_ptr->xbuffer[0][ci];
+    xbuf1 = main_ptr->xbuffer[1][ci];
     /* First copy the workspace pointers as-is */
-    buf = main->buffer[ci];
+    buf = main_ptr->buffer[ci];
     for (i = 0; i < rgroup * (M + 2); i++) {
       xbuf0[i] = xbuf1[i] = buf[i];
     }
     /* In the second list, put the last four row groups in swapped order */
     for (i = 0; i < rgroup * 2; i++) {
       xbuf1[rgroup*(M-2) + i] = buf[rgroup*M + i];
       xbuf1[rgroup*M + i] = buf[rgroup*(M-2) + i];
     }
     /* The wraparound pointers at top and bottom will be filled later
      * (see set_wraparound_pointers, below).  Initially we want the "above"
      * pointers to duplicate the first actual data line.  This only needs
      * to happen in xbuffer[0].
      */
     for (i = 0; i < rgroup; i++) {
       xbuf0[i - rgroup] = xbuf0[0];
     }
   }
 }
 
 
 LOCAL(void)
 set_wraparound_pointers (j_decompress_ptr cinfo)
 /* Set up the "wraparound" pointers at top and bottom of the pointer lists.
  * This changes the pointer list state from top-of-image to the normal state.
  */
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
   int ci, i, rgroup;
   int M = cinfo->_min_DCT_scaled_size;
   jpeg_component_info *compptr;
   JSAMPARRAY xbuf0, xbuf1;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) /
       cinfo->_min_DCT_scaled_size; /* height of a row group of component */
-    xbuf0 = main->xbuffer[0][ci];
-    xbuf1 = main->xbuffer[1][ci];
+    xbuf0 = main_ptr->xbuffer[0][ci];
+    xbuf1 = main_ptr->xbuffer[1][ci];
     for (i = 0; i < rgroup; i++) {
       xbuf0[i - rgroup] = xbuf0[rgroup*(M+1) + i];
       xbuf1[i - rgroup] = xbuf1[rgroup*(M+1) + i];
       xbuf0[rgroup*(M+2) + i] = xbuf0[i];
       xbuf1[rgroup*(M+2) + i] = xbuf1[i];
     }
   }
 }
 
 
 LOCAL(void)
 set_bottom_pointers (j_decompress_ptr cinfo)
 /* Change the pointer lists to duplicate the last sample row at the bottom
  * of the image.  whichptr indicates which xbuffer holds the final iMCU row.
  * Also sets rowgroups_avail to indicate number of nondummy row groups in row.
  */
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
   int ci, i, rgroup, iMCUheight, rows_left;
   jpeg_component_info *compptr;
   JSAMPARRAY xbuf;
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     /* Count sample rows in one iMCU row and in one row group */
     iMCUheight = compptr->v_samp_factor * compptr->_DCT_scaled_size;
     rgroup = iMCUheight / cinfo->_min_DCT_scaled_size;
     /* Count nondummy sample rows remaining for this component */
     rows_left = (int) (compptr->downsampled_height % (JDIMENSION) iMCUheight);
     if (rows_left == 0) rows_left = iMCUheight;
     /* Count nondummy row groups.  Should get same answer for each component,
      * so we need only do it once.
      */
     if (ci == 0) {
-      main->rowgroups_avail = (JDIMENSION) ((rows_left-1) / rgroup + 1);
+      main_ptr->rowgroups_avail = (JDIMENSION) ((rows_left-1) / rgroup + 1);
     }
     /* Duplicate the last real sample row rgroup*2 times; this pads out the
      * last partial rowgroup and ensures at least one full rowgroup of context.
      */
-    xbuf = main->xbuffer[main->whichptr][ci];
+    xbuf = main_ptr->xbuffer[main_ptr->whichptr][ci];
     for (i = 0; i < rgroup * 2; i++) {
       xbuf[rows_left + i] = xbuf[rows_left-1];
     }
   }
 }
 
 
 /*
  * Initialize for a processing pass.
  */
 
 METHODDEF(void)
 start_pass_main (j_decompress_ptr cinfo, J_BUF_MODE pass_mode)
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
 
   switch (pass_mode) {
   case JBUF_PASS_THRU:
     if (cinfo->upsample->need_context_rows) {
-      main->pub.process_data = process_data_context_main;
+      main_ptr->pub.process_data = process_data_context_main;
       make_funny_pointers(cinfo); /* Create the xbuffer[] lists */
-      main->whichptr = 0;       /* Read first iMCU row into xbuffer[0] */
-      main->context_state = CTX_PREPARE_FOR_IMCU;
-      main->iMCU_row_ctr = 0;
+      main_ptr->whichptr = 0;   /* Read first iMCU row into xbuffer[0] */
+      main_ptr->context_state = CTX_PREPARE_FOR_IMCU;
+      main_ptr->iMCU_row_ctr = 0;
     } else {
       /* Simple case with no context needed */
-      main->pub.process_data = process_data_simple_main;
+      main_ptr->pub.process_data = process_data_simple_main;
     }
-    main->buffer_full = FALSE;  /* Mark buffer empty */
-    main->rowgroup_ctr = 0;
+    main_ptr->buffer_full = FALSE;      /* Mark buffer empty */
+    main_ptr->rowgroup_ctr = 0;
     break;
 #ifdef QUANT_2PASS_SUPPORTED
   case JBUF_CRANK_DEST:
     /* For last pass of 2-pass quantization, just crank the postprocessor */
-    main->pub.process_data = process_data_crank_post;
+    main_ptr->pub.process_data = process_data_crank_post;
     break;
 #endif
   default:
     ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
     break;
   }
 }
 
 
 /*
  * Process some data.
  * This handles the simple case where no context is required.
  */
 
 METHODDEF(void)
 process_data_simple_main (j_decompress_ptr cinfo,
                           JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
                           JDIMENSION out_rows_avail)
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
   JDIMENSION rowgroups_avail;
 
   /* Read input data if we haven't filled the main buffer yet */
-  if (! main->buffer_full) {
-    if (! (*cinfo->coef->decompress_data) (cinfo, main->buffer))
+  if (! main_ptr->buffer_full) {
+    if (! (*cinfo->coef->decompress_data) (cinfo, main_ptr->buffer))
       return;                   /* suspension forced, can do nothing more */
-    main->buffer_full = TRUE;   /* OK, we have an iMCU row to work with */
+    main_ptr->buffer_full = TRUE;       /* OK, we have an iMCU row to work with */
   }
 
   /* There are always min_DCT_scaled_size row groups in an iMCU row. */
   rowgroups_avail = (JDIMENSION) cinfo->_min_DCT_scaled_size;
   /* Note: at the bottom of the image, we may pass extra garbage row groups
    * to the postprocessor.  The postprocessor has to check for bottom
    * of image anyway (at row resolution), so no point in us doing it too.
    */
 
   /* Feed the postprocessor */
-  (*cinfo->post->post_process_data) (cinfo, main->buffer,
-                                     &main->rowgroup_ctr, rowgroups_avail,
+  (*cinfo->post->post_process_data) (cinfo, main_ptr->buffer,
+                                     &main_ptr->rowgroup_ctr, rowgroups_avail,
                                      output_buf, out_row_ctr, out_rows_avail);
 
   /* Has postprocessor consumed all the data yet? If so, mark buffer empty */
-  if (main->rowgroup_ctr >= rowgroups_avail) {
-    main->buffer_full = FALSE;
-    main->rowgroup_ctr = 0;
+  if (main_ptr->rowgroup_ctr >= rowgroups_avail) {
+    main_ptr->buffer_full = FALSE;
+    main_ptr->rowgroup_ctr = 0;
   }
 }
 
 
 /*
  * Process some data.
  * This handles the case where context rows must be provided.
  */
 
 METHODDEF(void)
 process_data_context_main (j_decompress_ptr cinfo,
                            JSAMPARRAY output_buf, JDIMENSION *out_row_ctr,
                            JDIMENSION out_rows_avail)
 {
-  my_main_ptr main = (my_main_ptr) cinfo->main;
+  my_main_ptr main_ptr = (my_main_ptr) cinfo->main;
 
   /* Read input data if we haven't filled the main buffer yet */
-  if (! main->buffer_full) {
+  if (! main_ptr->buffer_full) {
     if (! (*cinfo->coef->decompress_data) (cinfo,
-                                           main->xbuffer[main->whichptr]))
+                                           main_ptr->xbuffer[main_ptr->whichptr]))
       return;                   /* suspension forced, can do nothing more */
-    main->buffer_full = TRUE;   /* OK, we have an iMCU row to work with */
-    main->iMCU_row_ctr++;       /* count rows received */
+    main_ptr->buffer_full = TRUE;       /* OK, we have an iMCU row to work with */
+    main_ptr->iMCU_row_ctr++;   /* count rows received */
   }
 
   /* Postprocessor typically will not swallow all the input data it is handed
    * in one call (due to filling the output buffer first).  Must be prepared
    * to exit and restart.  This switch lets us keep track of how far we got.
    * Note that each case falls through to the next on successful completion.
    */
-  switch (main->context_state) {
+  switch (main_ptr->context_state) {
   case CTX_POSTPONED_ROW:
     /* Call postprocessor using previously set pointers for postponed row */
-    (*cinfo->post->post_process_data) (cinfo, main->xbuffer[main->whichptr],
-                        &main->rowgroup_ctr, main->rowgroups_avail,
+    (*cinfo->post->post_process_data) (cinfo, main_ptr->xbuffer[main_ptr->whichptr],
+                        &main_ptr->rowgroup_ctr, main_ptr->rowgroups_avail,
                         output_buf, out_row_ctr, out_rows_avail);
-    if (main->rowgroup_ctr < main->rowgroups_avail)
+    if (main_ptr->rowgroup_ctr < main_ptr->rowgroups_avail)
       return;                   /* Need to suspend */
-    main->context_state = CTX_PREPARE_FOR_IMCU;
+    main_ptr->context_state = CTX_PREPARE_FOR_IMCU;
     if (*out_row_ctr >= out_rows_avail)
       return;                   /* Postprocessor exactly filled output buf */
     /*FALLTHROUGH*/
   case CTX_PREPARE_FOR_IMCU:
     /* Prepare to process first M-1 row groups of this iMCU row */
-    main->rowgroup_ctr = 0;
-    main->rowgroups_avail = (JDIMENSION) (cinfo->_min_DCT_scaled_size - 1);
+    main_ptr->rowgroup_ctr = 0;
+    main_ptr->rowgroups_avail = (JDIMENSION) (cinfo->_min_DCT_scaled_size - 1);
     /* Check for bottom of image: if so, tweak pointers to "duplicate"
      * the last sample row, and adjust rowgroups_avail to ignore padding rows.
      */
-    if (main->iMCU_row_ctr == cinfo->total_iMCU_rows)
+    if (main_ptr->iMCU_row_ctr == cinfo->total_iMCU_rows)
       set_bottom_pointers(cinfo);
-    main->context_state = CTX_PROCESS_IMCU;
+    main_ptr->context_state = CTX_PROCESS_IMCU;
     /*FALLTHROUGH*/
   case CTX_PROCESS_IMCU:
     /* Call postprocessor using previously set pointers */
-    (*cinfo->post->post_process_data) (cinfo, main->xbuffer[main->whichptr],
-                        &main->rowgroup_ctr, main->rowgroups_avail,
+    (*cinfo->post->post_process_data) (cinfo, main_ptr->xbuffer[main_ptr->whichptr],
+                        &main_ptr->rowgroup_ctr, main_ptr->rowgroups_avail,
                         output_buf, out_row_ctr, out_rows_avail);
-    if (main->rowgroup_ctr < main->rowgroups_avail)
+    if (main_ptr->rowgroup_ctr < main_ptr->rowgroups_avail)
       return;                   /* Need to suspend */
     /* After the first iMCU, change wraparound pointers to normal state */
-    if (main->iMCU_row_ctr == 1)
+    if (main_ptr->iMCU_row_ctr == 1)
       set_wraparound_pointers(cinfo);
     /* Prepare to load new iMCU row using other xbuffer list */
-    main->whichptr ^= 1;        /* 0=>1 or 1=>0 */
-    main->buffer_full = FALSE;
+    main_ptr->whichptr ^= 1;    /* 0=>1 or 1=>0 */
+    main_ptr->buffer_full = FALSE;
     /* Still need to process last row group of this iMCU row, */
     /* which is saved at index M+1 of the other xbuffer */
-    main->rowgroup_ctr = (JDIMENSION) (cinfo->_min_DCT_scaled_size + 1);
-    main->rowgroups_avail = (JDIMENSION) (cinfo->_min_DCT_scaled_size + 2);
-    main->context_state = CTX_POSTPONED_ROW;
+    main_ptr->rowgroup_ctr = (JDIMENSION) (cinfo->_min_DCT_scaled_size + 1);
+    main_ptr->rowgroups_avail = (JDIMENSION) (cinfo->_min_DCT_scaled_size + 2);
+    main_ptr->context_state = CTX_POSTPONED_ROW;
   }
 }
 
 
 /*
  * Process some data.
  * Final pass of two-pass quantization: just call the postprocessor.
  * Source data will be the postprocessor controller's internal buffer.
  */
 
@@ skipping 12 matching lines @@
 #endif /* QUANT_2PASS_SUPPORTED */
 
 
 /*
  * Initialize main buffer controller.
  */
 
 GLOBAL(void)
 jinit_d_main_controller (j_decompress_ptr cinfo, boolean need_full_buffer)
 {
-  my_main_ptr main;
+  my_main_ptr main_ptr;
   int ci, rgroup, ngroups;
   jpeg_component_info *compptr;
 
-  main = (my_main_ptr)
+  main_ptr = (my_main_ptr)
     (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE,
                                 SIZEOF(my_main_controller));
-  cinfo->main = (struct jpeg_d_main_controller *) main;
-  main->pub.start_pass = start_pass_main;
+  cinfo->main = (struct jpeg_d_main_controller *) main_ptr;
+  main_ptr->pub.start_pass = start_pass_main;
 
   if (need_full_buffer)         /* shouldn't happen */
     ERREXIT(cinfo, JERR_BAD_BUFFER_MODE);
 
   /* Allocate the workspace.
    * ngroups is the number of row groups we need.
    */
   if (cinfo->upsample->need_context_rows) {
     if (cinfo->_min_DCT_scaled_size < 2) /* unsupported, see comments above */
       ERREXIT(cinfo, JERR_NOTIMPL);
     alloc_funny_pointers(cinfo); /* Alloc space for xbuffer[] lists */
     ngroups = cinfo->_min_DCT_scaled_size + 2;
   } else {
     ngroups = cinfo->_min_DCT_scaled_size;
   }
 
   for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
        ci++, compptr++) {
     rgroup = (compptr->v_samp_factor * compptr->_DCT_scaled_size) /
       cinfo->_min_DCT_scaled_size; /* height of a row group of component */
-    main->buffer[ci] = (*cinfo->mem->alloc_sarray)
+    main_ptr->buffer[ci] = (*cinfo->mem->alloc_sarray)
                         ((j_common_ptr) cinfo, JPOOL_IMAGE,
                          compptr->width_in_blocks * compptr->_DCT_scaled_size,
                          (JDIMENSION) (rgroup * ngroups));
   }
 }