#include "llvm/Support/Regex.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/ADT/SmallVector.h"
#include "regex_impl.h"
#include <string>
using namespace llvm;
Regex::Regex(StringRef regex, unsigned Flags) {
unsigned flags = 0;
preg = new llvm_regex();
preg->re_endp = regex.end();
if (Flags & IgnoreCase)
flags |= REG_ICASE;
if (Flags & Newline)
flags |= REG_NEWLINE;
error = llvm_regcomp(preg, regex.data(), flags|REG_EXTENDED|REG_PEND);
}
Regex::~Regex() {
llvm_regfree(preg);
delete preg;
}
bool Regex::isValid(std::string &Error) {
if (!error)
return true;
size_t len = llvm_regerror(error, preg, NULL, 0);
Error.resize(len);
llvm_regerror(error, preg, &Error[0], len);
return false;
}
unsigned Regex::getNumMatches() const {
return preg->re_nsub;
}
bool Regex::match(StringRef String, SmallVectorImpl<StringRef> *Matches){
unsigned nmatch = Matches ? preg->re_nsub+1 : 0;
SmallVector<llvm_regmatch_t, 8> pm;
pm.resize(nmatch > 0 ? nmatch : 1);
pm[0].rm_so = 0;
pm[0].rm_eo = String.size();
int rc = llvm_regexec(preg, String.data(), nmatch, pm.data(), REG_STARTEND);
if (rc == REG_NOMATCH)
return false;
if (rc != 0) {
error = rc;
return false;
}
if (Matches) { Matches->clear();
for (unsigned i = 0; i != nmatch; ++i) {
if (pm[i].rm_so == -1) {
Matches->push_back(StringRef());
continue;
}
assert(pm[i].rm_eo >= pm[i].rm_so);
Matches->push_back(StringRef(String.data()+pm[i].rm_so,
pm[i].rm_eo-pm[i].rm_so));
}
}
return true;
}
std::string Regex::sub(StringRef Repl, StringRef String,
std::string *Error) {
SmallVector<StringRef, 8> Matches;
if (Error && !Error->empty()) *Error = "";
if (!match(String, &Matches))
return String;
std::string Res(String.begin(), Matches[0].begin());
while (!Repl.empty()) {
std::pair<StringRef, StringRef> Split = Repl.split('\\');
Res += Split.first;
if (Split.second.empty()) {
if (Repl.size() != Split.first.size() &&
Error && Error->empty())
*Error = "replacement string contained trailing backslash";
break;
}
Repl = Split.second;
switch (Repl[0]) {
default:
Res += Repl[0];
Repl = Repl.substr(1);
break;
case 't':
Res += '\t';
Repl = Repl.substr(1);
break;
case 'n':
Res += '\n';
Repl = Repl.substr(1);
break;
case '0': case '1': case '2': case '3': case '4':
case '5': case '6': case '7': case '8': case '9': {
StringRef Ref = Repl.slice(0, Repl.find_first_not_of("0123456789"));
Repl = Repl.substr(Ref.size());
unsigned RefValue;
if (!Ref.getAsInteger(10, RefValue) &&
RefValue < Matches.size())
Res += Matches[RefValue];
else if (Error && Error->empty())
*Error = "invalid backreference string '" + Ref.str() + "'";
break;
}
}
}
Res += StringRef(Matches[0].end(), String.end() - Matches[0].end());
return Res;
}