Add Assimp library in thirdparty

From https://github.com/assimp/assimp repo at d2b45377e4b09a1f43be95e45553afcc06b03f4b

thirdparty/assimp/code/RemoveComments.cpp

@@ -0,0 +1,113 @@
+/*
+Open Asset Import Library (assimp)
+----------------------------------------------------------------------
+
+Copyright (c) 2006-2019, assimp team
+
+
+All rights reserved.
+
+Redistribution and use of this software in source and binary forms,
+with or without modification, are permitted provided that the
+following conditions are met:
+
+* Redistributions of source code must retain the above
+  copyright notice, this list of conditions and the
+  following disclaimer.
+
+* Redistributions in binary form must reproduce the above
+  copyright notice, this list of conditions and the
+  following disclaimer in the documentation and/or other
+  materials provided with the distribution.
+
+* Neither the name of the assimp team, nor the names of its
+  contributors may be used to endorse or promote products
+  derived from this software without specific prior
+  written permission of the assimp team.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+----------------------------------------------------------------------
+*/
+
+/** @file  RemoveComments.cpp
+ *  @brief Defines the CommentRemover utility class
+ */
+
+#include <assimp/RemoveComments.h>
+#include <assimp/ParsingUtils.h>
+
+namespace Assimp    {
+
+// ------------------------------------------------------------------------------------------------
+// Remove line comments from a file
+void CommentRemover::RemoveLineComments(const char* szComment,
+    char* szBuffer, char chReplacement /* = ' ' */)
+{
+    // validate parameters
+    ai_assert(NULL != szComment && NULL != szBuffer && *szComment);
+
+    const size_t len = strlen(szComment);
+    while (*szBuffer)   {
+
+        // skip over quotes
+        if (*szBuffer == '\"' || *szBuffer == '\'')
+            while (*szBuffer++ && *szBuffer != '\"' && *szBuffer != '\'');
+
+        if (!strncmp(szBuffer,szComment,len)) {
+            while (!IsLineEnd(*szBuffer))
+                *szBuffer++ = chReplacement;
+
+            if (!*szBuffer) {
+                break;
+            }
+        }
+        ++szBuffer;
+    }
+}
+
+// ------------------------------------------------------------------------------------------------
+// Remove multi-line comments from a file
+void CommentRemover::RemoveMultiLineComments(const char* szCommentStart,
+    const char* szCommentEnd,char* szBuffer,
+    char chReplacement)
+{
+    // validate parameters
+    ai_assert(NULL != szCommentStart && NULL != szCommentEnd &&
+        NULL != szBuffer && *szCommentStart && *szCommentEnd);
+
+    const size_t len  = strlen(szCommentEnd);
+    const size_t len2 = strlen(szCommentStart);
+
+    while (*szBuffer)   {
+        // skip over quotes
+        if (*szBuffer == '\"' || *szBuffer == '\'')
+            while (*szBuffer++ && *szBuffer != '\"' && *szBuffer != '\'');
+
+        if (!strncmp(szBuffer,szCommentStart,len2))  {
+            while (*szBuffer) {
+                if (!::strncmp(szBuffer,szCommentEnd,len)) {
+                    for (unsigned int i = 0; i < len;++i)
+                        *szBuffer++ = chReplacement;
+
+                    break;
+                }
+            *szBuffer++ = chReplacement;
+            }
+            continue;
+        }
+        ++szBuffer;
+    }
+}
+
+} // !! Assimp