Patch #27397: Improved DPX/Cineon code

Patch by Julien Enche, thanks!

From the patch comment:

It allows Blender to load:
- 1, 8, 10, 12 and 16 bits files. For 10 and 12 bits files, packed or
  filled type A/B are supported.
- RGB, Log, Luma and YCbCr colorspaces.
- Big and little endian storage.
- Multi-elements (planar) storage.

It allows Blender to save :
- 8, 10, 12 and 16 bits file. For 10 and 12 bits files, the most used
  type A padding is used.
- RGB and Log colorspaces (Cineon can only be saved in Log colorspace).
  For Log colorspace, the common default values are used for gamma,
  reference black and reference white (respectively 1.7, 95 and 685 for
  10 bits files).
- Saved DPX/Cineon files now match the viewer.

Some files won't load (mostly because I haven't seen any of them):
- Compressed files
- 32 and 64 bits files
- Image orientation information are not taken in account. Here too,
  I haven't seen any file that was not top-bottom/left-right oriented.

1 files changed, 89 insertions, 51 deletions

diff --git a/source/blender/imbuf/intern/cineon/logmemfile.c b/source/blender/imbuf/intern/cineon/logmemfile.c
index a9938582f2a..54bc62276cf 100644
--- a/source/blender/imbuf/intern/cineon/logmemfile.c
+++ b/source/blender/imbuf/intern/cineon/logmemfile.c
@@ -1,21 +1,23 @@
 /*
- *	 Cineon image file format library routines.
+ * Cineon image file format library routines.
  *
- *	 Copyright 2006 Joseph Eagar (joeedh@gmail.com)
+ * Copyright 2006 Joseph Eagar (joeedh@gmail.com)
  *
- *	 This program is free software; you can redistribute it and/or modify it
- *	 under the terms of the GNU General Public License as published by the Free
- *	 Software Foundation; either version 2 of the License, or (at your option)
- *	 any later version.
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
  *
- *	 This program is distributed in the hope that it will be useful, but
- *	 WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
- *	 or FITNESS FOR A PARTICULAR PURPOSE.	 See the GNU General Public License
- *	 for more details.
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * for more details.
  *
- *	 You should have received a copy of the GNU General Public License
- *	 along with this program; if not, write to the Free Software
- *	 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * Contributor(s): Julien Enche.
  *
  */
 
@@ -23,64 +25,100 @@
  *  \ingroup imbcineon
  */
 
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 
 #include "logImageCore.h"
+#include "logmemfile.h"
 
-#include "logmemfile.h" /* own include */
-
-int logimage_fseek(void* logfile, intptr_t offsett, int origin)
-{	
-	struct _Log_Image_File_t_ *file = (struct _Log_Image_File_t_*) logfile;
-	intptr_t offset = offsett;
-	
-	if (file->file) fseek(file->file, offset, origin);
-	else { /*we're seeking in memory*/
-		if (origin==SEEK_SET) {
-			if (offset > file->membuffersize) return 1;
-			file->memcursor = file->membuffer + offset;
-		}
-		else if (origin==SEEK_END) {
-			if (offset > file->membuffersize) return 1;
-			file->memcursor = (file->membuffer + file->membuffersize) - offset;
-		}
-		else if (origin==SEEK_CUR) {
-			uintptr_t pos = (uintptr_t)file->membuffer - (uintptr_t)file->memcursor;
-			if (pos + offset > file->membuffersize) return 1;
-			if (pos < 0) return 1;
-			file->memcursor += offset;
+int logimage_fseek(LogImageFile *logFile, intptr_t offset, int origin)
+{
+	if (logFile->file)
+		fseek(logFile->file, offset, origin);
+	else { /* we're seeking in memory */
+		if (origin == SEEK_SET) {
+			if (offset > logFile->memBufferSize)
+				return 1;
+			logFile->memCursor = logFile->memBuffer + offset;
+		} else if (origin == SEEK_END) {
+			if (offset > logFile->memBufferSize)
+				return 1;
+			logFile->memCursor = (logFile->memBuffer + logFile->memBufferSize) - offset;
+		} else if (origin == SEEK_CUR) {
+			uintptr_t pos = (uintptr_t)logFile->memCursor - (uintptr_t)logFile->memBuffer;
+			if (pos + offset > logFile->memBufferSize || pos < 0)
+				return 1;
+
+			logFile->memCursor += offset;
 		}
 	}
 	return 0;
 }
 
-int logimage_fwrite(void *buffer, unsigned int size, unsigned int count, void *logfile)
+int logimage_fwrite(void *buffer, size_t size, unsigned int count, LogImageFile* logFile)
 {
-	struct _Log_Image_File_t_ *file = (struct _Log_Image_File_t_*) logfile;
-	if (file->file) return fwrite(buffer, size, count, file->file);
+	if (logFile->file)
+		return fwrite(buffer, size, count, logFile->file);
 	else { /*we're writing to memory*/
 		/*do nothing as this isn't supported yet*/
 		return count;
 	}
 }
 
-int logimage_fread(void *buffer, unsigned int size, unsigned int count, void *logfile)
+int logimage_fread(void *buffer, size_t size, unsigned int count, LogImageFile *logFile)
 {
-	struct _Log_Image_File_t_ *file = (struct _Log_Image_File_t_*) logfile;
-	if (file->file) return fread(buffer, size, count, file->file);
-	else { /*we're reading from memory*/
-		int i;
-		/* we convert ot uchar just on the off chance some platform can't handle
-		 * pointer arithmetic with type (void*). */
-		unsigned char *buf = (unsigned char *) buffer; 
-		
-		for (i=0; i<count; i++) {
-			memcpy(buf, file->memcursor, size);
-			file->memcursor += size;
-			buf += size;
+	if (logFile->file) {
+		return fread(buffer, size, count, logFile->file);
+	}
+	else { /* we're reading from memory */
+		unsigned char *buf = (unsigned char*)buffer;
+		uintptr_t pos = (uintptr_t)logFile->memCursor - (uintptr_t)logFile->memBuffer;
+		size_t total_size = size * count;
+		if (pos + total_size > logFile->memBufferSize) {
+			/* how many elements can we read without overflow ? */
+			count = (logFile->memBufferSize - pos) / size;
+			/* recompute the size */
+			total_size = size * count;
 		}
+
+		if (total_size != 0)
+			memcpy(buf, logFile->memCursor, total_size);
+
 		return count;
 	}
 }
+
+int logimage_read_uchar(unsigned char *x, LogImageFile *logFile)
+{
+	uintptr_t pos = (uintptr_t)logFile->memCursor - (uintptr_t)logFile->memBuffer;
+	if (pos + sizeof(unsigned char) > logFile->memBufferSize)
+		return 1;
+
+	*x = *(unsigned char*)logFile->memCursor;
+	logFile->memCursor += sizeof(unsigned char);
+	return 0;
+}
+
+int logimage_read_ushort(unsigned short *x, LogImageFile *logFile)
+{
+	uintptr_t pos = (uintptr_t)logFile->memCursor - (uintptr_t)logFile->memBuffer;
+	if (pos + sizeof(unsigned short) > logFile->memBufferSize)
+		return 1;
+
+	*x = *(unsigned short*)logFile->memCursor;
+	logFile->memCursor += sizeof(unsigned short);
+	return 0;
+}
+
+int logimage_read_uint(unsigned int *x, LogImageFile *logFile)
+{
+	uintptr_t pos = (uintptr_t)logFile->memCursor - (uintptr_t)logFile->memBuffer;
+	if (pos + sizeof(unsigned int) > logFile->memBufferSize)
+		return 1;
+
+	*x = *(unsigned int*)logFile->memCursor;
+	logFile->memCursor += sizeof(unsigned int);
+	return 0;
+}