X-Git-Url: http://git.tdb.fi/?p=libs%2Fcore.git;a=blobdiff_plain;f=source%2Fstrings%2Fregex.cpp;h=67157c9b185e434adf995ec75eeb3f122869ea9a;hp=bfd25c7036bffc88fbe5ca4a7db0a8057295c6de;hb=dce2985e07e6184f000ef176451150710e21ee35;hpb=00e36d6bf092b98dfa413578d9af58d61cedbc13

diff --git a/source/strings/regex.cpp b/source/strings/regex.cpp
index bfd25c7..67157c9 100644
--- a/source/strings/regex.cpp
+++ b/source/strings/regex.cpp
@@ -1,6 +1,6 @@
-#include <stack>
 #include <limits>
-#include <msp/core/except.h>
+#include <list>
+#include <stack>
 #include "format.h"
 #include "regex.h"
 
@@ -13,16 +13,16 @@ template<typename T>
 void write_int(T n, Msp::Regex::Code &code)
 {
 	for(unsigned i=0; i<sizeof(T); ++i)
-		code += (n>>i*8)&0xFF;
+		code += (n>>(i*8))&0xFF;
 }
 
-/** Reads an integer from a Regex code stream, in little-endian order. */
+/** Reads an integer from a Regex code string, in little-endian order. */
 template<typename T>
 T read_int(Msp::Regex::Code::const_iterator &c)
 {
 	T result = 0;
 	for(unsigned i=0; i<sizeof(T); ++i)
-		result += (*c++)<<i*8;
+		result += (*c++)<<(i*8);
 	return result;
 }
 
@@ -31,6 +31,28 @@ T read_int(Msp::Regex::Code::const_iterator &c)
 
 namespace Msp {
 
+bad_regex::bad_regex(const string &w, const string &e, const string::const_iterator &i):
+	logic_error(w+"\n"+make_where(e, i))
+{ }
+
+string bad_regex::make_where(const string &e, const string::const_iterator &i)
+{
+	string result;
+	string::size_type offset = i-e.begin();
+	if(offset>40)
+	{
+		result = e.substr(offset-40, 60);
+		offset = 40;
+	}
+	else
+		result = e.substr(0, 60);
+	result += '\n';
+	result.append(offset, ' ');
+	result += '^';
+	return result;
+}
+
+
 Regex::Regex(const string &expr)
 {
 	n_groups = 0;
@@ -42,7 +64,7 @@ Regex::Regex(const string &expr)
 Regex::Code Regex::compile(const string &expr, string::const_iterator &iter, unsigned &group, bool branch)
 {
 	bool has_branches = false;
-	unsigned level = 0;
+	stack<string::const_iterator> parens;
 	bool escape = false;
 	unsigned bracket = 0;
 	string::const_iterator end;
@@ -62,19 +84,19 @@ Regex::Code Regex::compile(const string &expr, string::const_iterator &iter, uns
 		else if(*end=='\\')
 			escape = true;
 		else if(*end=='(')
-			++level;
+			parens.push(end);
 		else if(*end==')')
 		{
-			if(level==0)
+			if(parens.empty())
 			{
 				if(group==0)
-					throw InvalidParameterValue("Unexpected )");
+					throw bad_regex("unmatched ')'", expr, end);
 				else
 					break;
 			}
-			--level;
+			parens.pop();
 		}
-		else if(*end=='|' && level==0)
+		else if(*end=='|' && parens.empty())
 		{
 			if(branch)
 				break;
@@ -85,8 +107,8 @@ Regex::Code Regex::compile(const string &expr, string::const_iterator &iter, uns
 			bracket = 1;
 	}
 
-	if(level>0)
-		throw InvalidParameterValue("Unmatched (");
+	if(!parens.empty())
+		throw bad_regex("unmatched '('", expr, parens.top());
 
 	Code result;
 
@@ -107,7 +129,7 @@ Regex::Code Regex::compile(const string &expr, string::const_iterator &iter, uns
 
 			Count repeat_min = 1;
 			Count repeat_max = 1;
-			parse_repeat(i, repeat_min, repeat_max);
+			parse_repeat(expr, i, repeat_min, repeat_max);
 
 			for(unsigned j=0; j<repeat_min; ++j)
 				result += atom;
@@ -189,14 +211,14 @@ Regex::Code Regex::parse_atom(const string &expr, string::const_iterator &i, uns
 	if(*i=='\\')
 	{
 		if(++i==expr.end())
-			throw InvalidParameterValue("Stray backslash");
+			throw bad_regex("stray backslash", expr, i-1);
 		flag = true;
 	}
 
 	if(!flag)
 	{
 		if(*i=='*' || *i=='{' || *i=='}' || *i=='+' || *i=='?' || *i=='|' || *i==')')
-			throw InvalidParameterValue("Invalid atom");
+			throw bad_regex("invalid atom", expr, i);
 		else if(*i=='[')
 			return parse_brackets(expr, i);
 		else if(*i=='.')
@@ -225,7 +247,7 @@ Regex::Code Regex::parse_atom(const string &expr, string::const_iterator &i, uns
 	return result;
 }
 
-bool Regex::parse_repeat(string::const_iterator &i, Count &rmin, Count &rmax)
+bool Regex::parse_repeat(const string &expr, string::const_iterator &i, Count &rmin, Count &rmax)
 {
 	if(*i!='*' && *i!='+' && *i!='?' && *i!='{')
 		return false;
@@ -236,6 +258,8 @@ bool Regex::parse_repeat(string::const_iterator &i, Count &rmin, Count &rmax)
 		rmin = 0;
 	if(*i=='{')
 	{
+		string::const_iterator begin = i;
+
 		rmin = 0;
 		for(++i; isdigit(*i); ++i)
 			rmin = rmin*10+(*i-'0');
@@ -249,7 +273,7 @@ bool Regex::parse_repeat(string::const_iterator &i, Count &rmin, Count &rmax)
 				for(; isdigit(*i); ++i)
 					rmax = rmax*10+(*i-'0');
 				if(rmax<rmin)
-					throw InvalidParameterValue("Invalid bound");
+					throw bad_regex("invalid bound", expr, begin);
 			}
 			else
 				rmax = numeric_limits<Count>::max();
@@ -257,7 +281,7 @@ bool Regex::parse_repeat(string::const_iterator &i, Count &rmin, Count &rmax)
 		else
 			rmax = rmin;
 		if(*i!='}')
-			throw InvalidParameterValue("Invalid bound");
+			throw bad_regex("invalid bound", expr, begin);
 	}
 
 	++i;
@@ -267,6 +291,7 @@ bool Regex::parse_repeat(string::const_iterator &i, Count &rmin, Count &rmax)
 
 Regex::Code Regex::parse_brackets(const string &str, string::const_iterator &iter)
 {
+	string::const_iterator begin = iter;
 	Code result;
 
 	++iter;
@@ -280,12 +305,12 @@ Regex::Code Regex::parse_brackets(const string &str, string::const_iterator &ite
 	string::const_iterator end = iter;
 	for(; (end!=str.end() && (end==iter || *end!=']')); ++end) ;
 	if(end==str.end())
-		throw InvalidParameterValue("Unmatched '['");
+		throw bad_regex("unmatched '['", str, begin);
 
 	unsigned char mask[32] = {0};
 	unsigned type = 0;
 	bool range = false;
-	unsigned char first=0, last = 0;
+	unsigned char first = 0, last = 0;
 	for(string::const_iterator i=iter; i!=end; ++i)
 	{
 		unsigned char c = *i;
@@ -451,7 +476,7 @@ bool Regex::run(const string &str, const string::const_iterator &begin, RegMatch
 						input_consumed = true;
 					}
 					else
-						throw Exception("Invalid instruction");
+						throw logic_error("invalid instruction in regex bytecode");
 
 					if(match_result==negate_match)
 						terminate = true;