1 files changed, 18 insertions, 11 deletions

diff --git a/indra/llcommon/llstring.cpp b/indra/llcommon/llstring.cpp
index f3b48b0156..fa0eb9f72c 100644
--- a/indra/llcommon/llstring.cpp
+++ b/indra/llcommon/llstring.cpp
@@ -912,22 +912,24 @@ S32 LLStringUtil::format(std::string& s, const format_map_t& substitutions);
 template<> 
 void LLStringUtil::getTokens(const std::string& instr, std::vector<std::string >& tokens, const std::string& delims)
 {
-	std::string currToken;
-	std::string::size_type begIdx, endIdx;
-
-	begIdx = instr.find_first_not_of (delims);
-	while (begIdx != std::string::npos)
+	// Starting at offset 0, scan forward for the next non-delimiter. We're
+	// done when the only characters left in 'instr' are delimiters.
+	for (std::string::size_type begIdx, endIdx = 0;
+		 (begIdx = instr.find_first_not_of (delims, endIdx)) != std::string::npos; )
 	{
+		// Found a non-delimiter. After that, find the next delimiter.
 		endIdx = instr.find_first_of (delims, begIdx);
 		if (endIdx == std::string::npos)
 		{
+			// No more delimiters: this token extends to the end of the string.
 			endIdx = instr.length();
 		}
 
-		currToken = instr.substr(begIdx, endIdx - begIdx);
+		// extract the token between begIdx and endIdx; substr() needs length
+		std::string currToken(instr.substr(begIdx, endIdx - begIdx));
 		LLStringUtil::trim (currToken);
 		tokens.push_back(currToken);
-		begIdx = instr.find_first_not_of (delims, endIdx);
+		// next scan past delimiters starts at endIdx
 	}
 }
 
@@ -936,13 +938,18 @@ LLStringUtil::size_type LLStringUtil::getSubstitution(const std::string& instr,
 {
 	const std::string delims (",");
 	
-	// Find the first ]
-	size_type pos2 = instr.find(']', start);
+	// Find the first [
+	size_type pos1 = instr.find('[', start);
+	if (pos1 == std::string::npos)
+		return std::string::npos;
+
+	//Find the first ] after the initial [
+	size_type pos2 = instr.find(']', pos1);
 	if (pos2 == std::string::npos)
 		return std::string::npos;
 
-	// Find the last [ before ]
-	size_type pos1 = instr.find_last_of('[', pos2-1);
+	// Find the last [ before ] in case of nested [[]]
+	pos1 = instr.find_last_of('[', pos2-1);
 	if (pos1 == std::string::npos || pos1 < start)
 		return std::string::npos;