[gs-cvs] rev 8814 - trunk/gs/src

[leonardo at ghostscript.com]

Author: leonardo
Date: 2008-07-01 03:22:25 -0700 (Tue, 01 Jul 2008)
New Revision: 8814

Modified:
   trunk/gs/src/gdevp14.c
   trunk/gs/src/gstparam.h
Log:
Fix (clist writer) : The maximal compositor command size was wrong.

DETAILS :

Bug 689927 "rangecheck in c_pdf14trans_write() causing 'unregistered' error". 

The bug was introduced in revision 8587.
See comments in code.
Thanks to Ray and Marcos for participation.
 
EXPECTED DIFFERENCES :

None.


Modified: trunk/gs/src/gdevp14.c
===================================================================
--- trunk/gs/src/gdevp14.c	2008-06-30 23:56:04 UTC (rev 8813)
+++ trunk/gs/src/gdevp14.c	2008-07-01 10:22:25 UTC (rev 8814)
@@ -2927,19 +2927,16 @@
 {
     const gs_pdf14trans_params_t * pparams = &((const gs_pdf14trans_t *)pct)->params;
     int need, avail = *psize;
-	/* Must be large enough for largest data struct */
-    byte buf[25 /* See sput_matrix. */ +
-	     21 + sizeof(pparams->Background)
-		+ sizeof(pparams->GrayBackground) + sizeof(pparams->bbox)
-		+ sizeof(cdev->mask_id)];
+    byte buf[MAX_CLIST_TRANSPARENCY_BUFFER_SIZE]; /* Must be large enough 
+    	to fit the data written below. We don't implement a dynamic check for the buffer owerflow,
+	assuming that the consistency is verified in the coding phase. 
+	See the definition of MAX_CLIST_TRANSPARENCY_BUFFER_SIZE. */
     byte * pbuf = buf;
     int opcode = pparams->pdf14_op;
     int mask_size = 0;
     uint mask_id = 0;
     int code;
 
-    /* Write PDF 1.4 compositor data into the clist */
-
     *pbuf++ = opcode;			/* 1 byte */
     switch (opcode) {
 	default:			/* Should not occur. */

Modified: trunk/gs/src/gstparam.h
===================================================================
--- trunk/gs/src/gstparam.h	2008-06-30 23:56:04 UTC (rev 8813)
+++ trunk/gs/src/gstparam.h	2008-07-01 10:22:25 UTC (rev 8814)
@@ -123,7 +123,23 @@
     byte transfer_fn[MASK_TRANSFER_FUNCTION_SIZE];
 } gx_transparency_mask_params_t;
 
-#define MAX_CLIST_COMPOSITOR_SIZE (sizeof( gx_transparency_mask_params_t ) + 1)
+/*
+   The longest compositor command includes transparency mask parameters
+   (see gdevp14.c c_pdf14trans_write() the "case PDF14_BEGIN_TRANS_MASK").
+   Note that 'idle' is not written because it is generated by the clist interpreter.
+*/
+#define MAX_CLIST_TRANSPARENCY_BUFFER_SIZE ( \
+             4 /* the clist cmd prefix byte cmd_opv_extend + extended function + 2 bytes for band_id */ + \
+             1 + sizeof(float) * 6 /* See sput_matrix. */ + \
+             sizeof(((gs_pdf14trans_params_t *)0)->subtype) + \
+             3 /* replacing, function_is_identity, Background_components */ + \
+	     sizeof(((gs_pdf14trans_params_t *)0)->bbox) + \
+	     sizeof(((gs_pdf14trans_params_t *)0)->mask_id) + \
+	     sizeof(((gs_pdf14trans_params_t *)0)->Background) + \
+	     sizeof(((gs_pdf14trans_params_t *)0)->GrayBackground))	     
+#define MAX_CLIST_TRANSPARENCY_COMPOSITOR_SIZE (MAX_CLIST_TRANSPARENCY_BUFFER_SIZE + \
+	     sizeof(((gs_pdf14trans_params_t *)0)->transfer_fn))
+#define MAX_CLIST_COMPOSITOR_SIZE MAX_CLIST_TRANSPARENCY_COMPOSITOR_SIZE
 
 /* Select the opacity or shape parameters. */
 typedef enum {