Get rid of most instance of 'foo == NULL'

fpdfsdk/src/fpdftext.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "public/fpdf_text.h"
 
 #include "core/include/fpdfdoc/fpdf_doc.h"
 #include "core/include/fpdftext/fpdf_text.h"
@@ skipping 137 matching lines @@
                                               double bottom,
                                               unsigned short* buffer,
                                               int buflen) {
   if (!text_page)
     return 0;
   IPDF_TextPage* textpage = (IPDF_TextPage*)text_page;
   CFX_FloatRect rect((FX_FLOAT)left, (FX_FLOAT)bottom, (FX_FLOAT)right,
                      (FX_FLOAT)top);
   CFX_WideString str = textpage->GetTextByRect(rect);
 
-  if (buflen <= 0 || buffer == NULL) {
+  if (buflen <= 0 || !buffer) {
     return str.GetLength();
   }
 
   CFX_ByteString cbUTF16Str = str.UTF16LE_Encode();
   int len = cbUTF16Str.GetLength() / sizeof(unsigned short);
   int size = buflen > len ? len : buflen;
   FXSYS_memcpy(buffer, cbUTF16Str.GetBuffer(size * sizeof(unsigned short)),
                size * sizeof(unsigned short));
   cbUTF16Str.ReleaseBuffer(size * sizeof(unsigned short));
 
@@ skipping 66 matching lines @@
                                       int link_index,
                                       unsigned short* buffer,
                                       int buflen) {
   if (!link_page)
     return 0;
   IPDF_LinkExtract* pageLink = (IPDF_LinkExtract*)link_page;
   CFX_WideString url = pageLink->GetURL(link_index);
 
   CFX_ByteString cbUTF16URL = url.UTF16LE_Encode();
   int len = cbUTF16URL.GetLength() / sizeof(unsigned short);
-  if (buffer == NULL || buflen <= 0)
+  if (!buffer || buflen <= 0)
     return len;
   int size = len < buflen ? len : buflen;
   if (size > 0) {
     FXSYS_memcpy(buffer, cbUTF16URL.GetBuffer(size * sizeof(unsigned short)),
                  size * sizeof(unsigned short));
     cbUTF16URL.ReleaseBuffer(size * sizeof(unsigned short));
   }
   return size;
 }
 DLLEXPORT int STDCALL FPDFLink_CountRects(FPDF_PAGELINK link_page,
@@ skipping 21 matching lines @@
     CFX_FloatRect rect = rectArray.GetAt(rect_index);
     *left = rect.left;
     *right = rect.right;
     *top = rect.top;
     *bottom = rect.bottom;
   }
 }
 DLLEXPORT void STDCALL FPDFLink_CloseWebLinks(FPDF_PAGELINK link_page) {
   delete (IPDF_LinkExtract*)link_page;
 }