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+// Copyright 2003-2009 Google Inc. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+// This is a variant of PCRE's pcrecpp.cc, originally written at Google.
+// The main changes are the addition of the HitLimit method and
+// compilation as PCRE in namespace re2.
+
+#include <errno.h>
+#include "util/util.h"
+#include "util/flags.h"
+#include "util/pcre.h"
+
+#define PCREPORT(level) LOG(level)
+
+// Default PCRE limits.
+// Defaults chosen to allow a plausible amount of CPU and
+// not exceed main thread stacks. Note that other threads
+// often have smaller stacks, and therefore tightening
+// regexp_stack_limit may frequently be necessary.
+DEFINE_int32(regexp_stack_limit, 256<<10, "default PCRE stack limit (bytes)");
+DEFINE_int32(regexp_match_limit, 1000000,
+ "default PCRE match limit (function calls)");
+
+namespace re2 {
+
+// Maximum number of args we can set
+static const int kMaxArgs = 16;
+static const int kVecSize = (1 + kMaxArgs) * 3; // results + PCRE workspace
+
+// Approximate size of a recursive invocation of PCRE's
+// internal "match()" frame. This varies depending on the
+// compiler and architecture, of course, so the constant is
+// just a conservative estimate. To find the exact number,
+// run regexp_unittest with --regexp_stack_limit=0 under
+// a debugger and look at the frames when it crashes.
+// The exact frame size was 656 in production on 2008/02/03.
+static const int kPCREFrameSize = 700;
+
+// Special name for missing C++ arguments.
+PCRE::Arg PCRE::no_more_args((void*)NULL);
+
+const PCRE::PartialMatchFunctor PCRE::PartialMatch = { };
+const PCRE::FullMatchFunctor PCRE::FullMatch = { } ;
+const PCRE::ConsumeFunctor PCRE::Consume = { };
+const PCRE::FindAndConsumeFunctor PCRE::FindAndConsume = { };
+
+// If a regular expression has no error, its error_ field points here
+static const string empty_string;
+
+void PCRE::Init(const char* pattern, Option options, int match_limit,
+ int stack_limit, bool report_errors) {
+ pattern_ = pattern;
+ options_ = options;
+ match_limit_ = match_limit;
+ stack_limit_ = stack_limit;
+ hit_limit_ = false;
+ error_ = &empty_string;
+ report_errors_ = report_errors;
+ re_full_ = NULL;
+ re_partial_ = NULL;
+
+ if (options & ~(EnabledCompileOptions | EnabledExecOptions)) {
+ error_ = new string("illegal regexp option");
+ PCREPORT(ERROR)
+ << "Error compiling '" << pattern << "': illegal regexp option";
+ } else {
+ re_partial_ = Compile(UNANCHORED);
+ if (re_partial_ != NULL) {
+ re_full_ = Compile(ANCHOR_BOTH);
+ }
+ }
+}
+
+PCRE::PCRE(const char* pattern) {
+ Init(pattern, None, 0, 0, true);
+}
+PCRE::PCRE(const char* pattern, Option option) {
+ Init(pattern, option, 0, 0, true);
+}
+PCRE::PCRE(const string& pattern) {
+ Init(pattern.c_str(), None, 0, 0, true);
+}
+PCRE::PCRE(const string& pattern, Option option) {
+ Init(pattern.c_str(), option, 0, 0, true);
+}
+PCRE::PCRE(const string& pattern, const PCRE_Options& re_option) {
+ Init(pattern.c_str(), re_option.option(), re_option.match_limit(),
+ re_option.stack_limit(), re_option.report_errors());
+}
+
+PCRE::PCRE(const char *pattern, const PCRE_Options& re_option) {
+ Init(pattern, re_option.option(), re_option.match_limit(),
+ re_option.stack_limit(), re_option.report_errors());
+}
+
+PCRE::~PCRE() {
+ if (re_full_ != NULL) pcre_free(re_full_);
+ if (re_partial_ != NULL) pcre_free(re_partial_);
+ if (error_ != &empty_string) delete error_;
+}
+
+pcre* PCRE::Compile(Anchor anchor) {
+ // Special treatment for anchoring. This is needed because at
+ // runtime pcre only provides an option for anchoring at the
+ // beginning of a string.
+ //
+ // There are three types of anchoring we want:
+ // UNANCHORED Compile the original pattern, and use
+ // a pcre unanchored match.
+ // ANCHOR_START Compile the original pattern, and use
+ // a pcre anchored match.
+ // ANCHOR_BOTH Tack a "\z" to the end of the original pattern
+ // and use a pcre anchored match.
+
+ const char* error;
+ int eoffset;
+ pcre* re;
+ if (anchor != ANCHOR_BOTH) {
+ re = pcre_compile(pattern_.c_str(),
+ (options_ & EnabledCompileOptions),
+ &error, &eoffset, NULL);
+ } else {
+ // Tack a '\z' at the end of PCRE. Parenthesize it first so that
+ // the '\z' applies to all top-level alternatives in the regexp.
+ string wrapped = "(?:"; // A non-counting grouping operator
+ wrapped += pattern_;
+ wrapped += ")\\z";
+ re = pcre_compile(wrapped.c_str(),
+ (options_ & EnabledCompileOptions),
+ &error, &eoffset, NULL);
+ }
+ if (re == NULL) {
+ if (error_ == &empty_string) error_ = new string(error);
+ PCREPORT(ERROR) << "Error compiling '" << pattern_ << "': " << error;
+ }
+ return re;
+}
+
+/***** Convenience interfaces *****/
+
+bool PCRE::FullMatchFunctor::operator ()(const StringPiece& text,
+ const PCRE& re,
+ const Arg& a0,
+ const Arg& a1,
+ const Arg& a2,
+ const Arg& a3,
+ const Arg& a4,
+ const Arg& a5,
+ const Arg& a6,
+ const Arg& a7,
+ const Arg& a8,
+ const Arg& a9,
+ const Arg& a10,
+ const Arg& a11,
+ const Arg& a12,
+ const Arg& a13,
+ const Arg& a14,
+ const Arg& a15) const {
+ const Arg* args[kMaxArgs];
+ int n = 0;
+ if (&a0 == &no_more_args) goto done; args[n++] = &a0;
+ if (&a1 == &no_more_args) goto done; args[n++] = &a1;
+ if (&a2 == &no_more_args) goto done; args[n++] = &a2;
+ if (&a3 == &no_more_args) goto done; args[n++] = &a3;
+ if (&a4 == &no_more_args) goto done; args[n++] = &a4;
+ if (&a5 == &no_more_args) goto done; args[n++] = &a5;
+ if (&a6 == &no_more_args) goto done; args[n++] = &a6;
+ if (&a7 == &no_more_args) goto done; args[n++] = &a7;
+ if (&a8 == &no_more_args) goto done; args[n++] = &a8;
+ if (&a9 == &no_more_args) goto done; args[n++] = &a9;
+ if (&a10 == &no_more_args) goto done; args[n++] = &a10;
+ if (&a11 == &no_more_args) goto done; args[n++] = &a11;
+ if (&a12 == &no_more_args) goto done; args[n++] = &a12;
+ if (&a13 == &no_more_args) goto done; args[n++] = &a13;
+ if (&a14 == &no_more_args) goto done; args[n++] = &a14;
+ if (&a15 == &no_more_args) goto done; args[n++] = &a15;
+done:
+
+ int consumed;
+ int vec[kVecSize];
+ return re.DoMatchImpl(text, ANCHOR_BOTH, &consumed, args, n, vec, kVecSize);
+}
+
+bool PCRE::PartialMatchFunctor::operator ()(const StringPiece& text,
+ const PCRE& re,
+ const Arg& a0,
+ const Arg& a1,
+ const Arg& a2,
+ const Arg& a3,
+ const Arg& a4,
+ const Arg& a5,
+ const Arg& a6,
+ const Arg& a7,
+ const Arg& a8,
+ const Arg& a9,
+ const Arg& a10,
+ const Arg& a11,
+ const Arg& a12,
+ const Arg& a13,
+ const Arg& a14,
+ const Arg& a15) const {
+ const Arg* args[kMaxArgs];
+ int n = 0;
+ if (&a0 == &no_more_args) goto done; args[n++] = &a0;
+ if (&a1 == &no_more_args) goto done; args[n++] = &a1;
+ if (&a2 == &no_more_args) goto done; args[n++] = &a2;
+ if (&a3 == &no_more_args) goto done; args[n++] = &a3;
+ if (&a4 == &no_more_args) goto done; args[n++] = &a4;
+ if (&a5 == &no_more_args) goto done; args[n++] = &a5;
+ if (&a6 == &no_more_args) goto done; args[n++] = &a6;
+ if (&a7 == &no_more_args) goto done; args[n++] = &a7;
+ if (&a8 == &no_more_args) goto done; args[n++] = &a8;
+ if (&a9 == &no_more_args) goto done; args[n++] = &a9;
+ if (&a10 == &no_more_args) goto done; args[n++] = &a10;
+ if (&a11 == &no_more_args) goto done; args[n++] = &a11;
+ if (&a12 == &no_more_args) goto done; args[n++] = &a12;
+ if (&a13 == &no_more_args) goto done; args[n++] = &a13;
+ if (&a14 == &no_more_args) goto done; args[n++] = &a14;
+ if (&a15 == &no_more_args) goto done; args[n++] = &a15;
+done:
+
+ int consumed;
+ int vec[kVecSize];
+ return re.DoMatchImpl(text, UNANCHORED, &consumed, args, n, vec, kVecSize);
+}
+
+bool PCRE::ConsumeFunctor::operator ()(StringPiece* input,
+ const PCRE& pattern,
+ const Arg& a0,
+ const Arg& a1,
+ const Arg& a2,
+ const Arg& a3,
+ const Arg& a4,
+ const Arg& a5,
+ const Arg& a6,
+ const Arg& a7,
+ const Arg& a8,
+ const Arg& a9,
+ const Arg& a10,
+ const Arg& a11,
+ const Arg& a12,
+ const Arg& a13,
+ const Arg& a14,
+ const Arg& a15) const {
+ const Arg* args[kMaxArgs];
+ int n = 0;
+ if (&a0 == &no_more_args) goto done; args[n++] = &a0;
+ if (&a1 == &no_more_args) goto done; args[n++] = &a1;
+ if (&a2 == &no_more_args) goto done; args[n++] = &a2;
+ if (&a3 == &no_more_args) goto done; args[n++] = &a3;
+ if (&a4 == &no_more_args) goto done; args[n++] = &a4;
+ if (&a5 == &no_more_args) goto done; args[n++] = &a5;
+ if (&a6 == &no_more_args) goto done; args[n++] = &a6;
+ if (&a7 == &no_more_args) goto done; args[n++] = &a7;
+ if (&a8 == &no_more_args) goto done; args[n++] = &a8;
+ if (&a9 == &no_more_args) goto done; args[n++] = &a9;
+ if (&a10 == &no_more_args) goto done; args[n++] = &a10;
+ if (&a11 == &no_more_args) goto done; args[n++] = &a11;
+ if (&a12 == &no_more_args) goto done; args[n++] = &a12;
+ if (&a13 == &no_more_args) goto done; args[n++] = &a13;
+ if (&a14 == &no_more_args) goto done; args[n++] = &a14;
+ if (&a15 == &no_more_args) goto done; args[n++] = &a15;
+done:
+
+ int consumed;
+ int vec[kVecSize];
+ if (pattern.DoMatchImpl(*input, ANCHOR_START, &consumed,
+ args, n, vec, kVecSize)) {
+ input->remove_prefix(consumed);
+ return true;
+ } else {
+ return false;
+ }
+}
+
+bool PCRE::FindAndConsumeFunctor::operator ()(StringPiece* input,
+ const PCRE& pattern,
+ const Arg& a0,
+ const Arg& a1,
+ const Arg& a2,
+ const Arg& a3,
+ const Arg& a4,
+ const Arg& a5,
+ const Arg& a6,
+ const Arg& a7,
+ const Arg& a8,
+ const Arg& a9,
+ const Arg& a10,
+ const Arg& a11,
+ const Arg& a12,
+ const Arg& a13,
+ const Arg& a14,
+ const Arg& a15) const {
+ const Arg* args[kMaxArgs];
+ int n = 0;
+ if (&a0 == &no_more_args) goto done; args[n++] = &a0;
+ if (&a1 == &no_more_args) goto done; args[n++] = &a1;
+ if (&a2 == &no_more_args) goto done; args[n++] = &a2;
+ if (&a3 == &no_more_args) goto done; args[n++] = &a3;
+ if (&a4 == &no_more_args) goto done; args[n++] = &a4;
+ if (&a5 == &no_more_args) goto done; args[n++] = &a5;
+ if (&a6 == &no_more_args) goto done; args[n++] = &a6;
+ if (&a7 == &no_more_args) goto done; args[n++] = &a7;
+ if (&a8 == &no_more_args) goto done; args[n++] = &a8;
+ if (&a9 == &no_more_args) goto done; args[n++] = &a9;
+ if (&a10 == &no_more_args) goto done; args[n++] = &a10;
+ if (&a11 == &no_more_args) goto done; args[n++] = &a11;
+ if (&a12 == &no_more_args) goto done; args[n++] = &a12;
+ if (&a13 == &no_more_args) goto done; args[n++] = &a13;
+ if (&a14 == &no_more_args) goto done; args[n++] = &a14;
+ if (&a15 == &no_more_args) goto done; args[n++] = &a15;
+done:
+
+ int consumed;
+ int vec[kVecSize];
+ if (pattern.DoMatchImpl(*input, UNANCHORED, &consumed,
+ args, n, vec, kVecSize)) {
+ input->remove_prefix(consumed);
+ return true;
+ } else {
+ return false;
+ }
+}
+
+bool PCRE::Replace(string *str,
+ const PCRE& pattern,
+ const StringPiece& rewrite) {
+ int vec[kVecSize];
+ int matches = pattern.TryMatch(*str, 0, UNANCHORED, true, vec, kVecSize);
+ if (matches == 0)
+ return false;
+
+ string s;
+ if (!pattern.Rewrite(&s, rewrite, *str, vec, matches))
+ return false;
+
+ assert(vec[0] >= 0);
+ assert(vec[1] >= 0);
+ str->replace(vec[0], vec[1] - vec[0], s);
+ return true;
+}
+
+int PCRE::GlobalReplace(string *str,
+ const PCRE& pattern,
+ const StringPiece& rewrite) {
+ int count = 0;
+ int vec[kVecSize];
+ string out;
+ int start = 0;
+ bool last_match_was_empty_string = false;
+
+ for (; start <= str->length();) {
+ // If the previous match was for the empty string, we shouldn't
+ // just match again: we'll match in the same way and get an
+ // infinite loop. Instead, we do the match in a special way:
+ // anchored -- to force another try at the same position --
+ // and with a flag saying that this time, ignore empty matches.
+ // If this special match returns, that means there's a non-empty
+ // match at this position as well, and we can continue. If not,
+ // we do what perl does, and just advance by one.
+ // Notice that perl prints '@@@' for this;
+ // perl -le '$_ = "aa"; s/b*|aa/@/g; print'
+ int matches;
+ if (last_match_was_empty_string) {
+ matches = pattern.TryMatch(*str, start, ANCHOR_START, false,
+ vec, kVecSize);
+ if (matches <= 0) {
+ if (start < str->length())
+ out.push_back((*str)[start]);
+ start++;
+ last_match_was_empty_string = false;
+ continue;
+ }
+ } else {
+ matches = pattern.TryMatch(*str, start, UNANCHORED, true, vec, kVecSize);
+ if (matches <= 0)
+ break;
+ }
+ int matchstart = vec[0], matchend = vec[1];
+ assert(matchstart >= start);
+ assert(matchend >= matchstart);
+
+ out.append(*str, start, matchstart - start);
+ pattern.Rewrite(&out, rewrite, *str, vec, matches);
+ start = matchend;
+ count++;
+ last_match_was_empty_string = (matchstart == matchend);
+ }
+
+ if (count == 0)
+ return 0;
+
+ if (start < str->length())
+ out.append(*str, start, str->length() - start);
+ swap(out, *str);
+ return count;
+}
+
+bool PCRE::Extract(const StringPiece &text,
+ const PCRE& pattern,
+ const StringPiece &rewrite,
+ string *out) {
+ int vec[kVecSize];
+ int matches = pattern.TryMatch(text, 0, UNANCHORED, true, vec, kVecSize);
+ if (matches == 0)
+ return false;
+ out->clear();
+ return pattern.Rewrite(out, rewrite, text, vec, matches);
+}
+
+string PCRE::QuoteMeta(const StringPiece& unquoted) {
+ string result;
+ result.reserve(unquoted.size() << 1);
+
+ // Escape any ascii character not in [A-Za-z_0-9].
+ //
+ // Note that it's legal to escape a character even if it has no
+ // special meaning in a regular expression -- so this function does
+ // that. (This also makes it identical to the perl function of the
+ // same name except for the null-character special case;
+ // see `perldoc -f quotemeta`.)
+ for (int ii = 0; ii < unquoted.length(); ++ii) {
+ // Note that using 'isalnum' here raises the benchmark time from
+ // 32ns to 58ns:
+ if ((unquoted[ii] < 'a' || unquoted[ii] > 'z') &&
+ (unquoted[ii] < 'A' || unquoted[ii] > 'Z') &&
+ (unquoted[ii] < '0' || unquoted[ii] > '9') &&
+ unquoted[ii] != '_' &&
+ // If this is the part of a UTF8 or Latin1 character, we need
+ // to copy this byte without escaping. Experimentally this is
+ // what works correctly with the regexp library.
+ !(unquoted[ii] & 128)) {
+ if (unquoted[ii] == '\0') { // Special handling for null chars.
+ // Can't use "\\0" since the next character might be a digit.
+ result += "\\x00";
+ continue;
+ }
+ result += '\\';
+ }
+ result += unquoted[ii];
+ }
+
+ return result;
+}
+
+/***** Actual matching and rewriting code *****/
+
+bool PCRE::HitLimit() {
+ return hit_limit_;
+}
+
+void PCRE::ClearHitLimit() {
+ hit_limit_ = 0;
+}
+
+int PCRE::TryMatch(const StringPiece& text,
+ int startpos,
+ Anchor anchor,
+ bool empty_ok,
+ int *vec,
+ int vecsize) const {
+ pcre* re = (anchor == ANCHOR_BOTH) ? re_full_ : re_partial_;
+ if (re == NULL) {
+ PCREPORT(ERROR) << "Matching against invalid re: " << *error_;
+ return 0;
+ }
+
+ int match_limit = match_limit_;
+ if (match_limit <= 0) {
+ match_limit = FLAGS_regexp_match_limit;
+ }
+
+ int stack_limit = stack_limit_;
+ if (stack_limit <= 0) {
+ stack_limit = FLAGS_regexp_stack_limit;
+ }
+
+ pcre_extra extra = { 0 };
+ if (match_limit > 0) {
+ extra.flags |= PCRE_EXTRA_MATCH_LIMIT;
+ extra.match_limit = match_limit;
+ }
+ if (stack_limit > 0) {
+ extra.flags |= PCRE_EXTRA_MATCH_LIMIT_RECURSION;
+ extra.match_limit_recursion = stack_limit / kPCREFrameSize;
+ }
+
+ int options = 0;
+ if (anchor != UNANCHORED)
+ options |= PCRE_ANCHORED;
+ if (!empty_ok)
+ options |= PCRE_NOTEMPTY;
+
+ int rc = pcre_exec(re, // The regular expression object
+ &extra,
+ (text.data() == NULL) ? "" : text.data(),
+ text.size(),
+ startpos,
+ options,
+ vec,
+ vecsize);
+
+ // Handle errors
+ if (rc == 0) {
+ // pcre_exec() returns 0 as a special case when the number of
+ // capturing subpatterns exceeds the size of the vector.
+ // When this happens, there is a match and the output vector
+ // is filled, but we miss out on the positions of the extra subpatterns.
+ rc = vecsize / 2;
+ } else if (rc < 0) {
+ switch (rc) {
+ case PCRE_ERROR_NOMATCH:
+ return 0;
+ case PCRE_ERROR_MATCHLIMIT:
+ // Writing to hit_limit is not safe if multiple threads
+ // are using the PCRE, but the flag is only intended
+ // for use by unit tests anyway, so we let it go.
+ hit_limit_ = true;
+ PCREPORT(WARNING) << "Exceeded match limit of " << match_limit
+ << " when matching '" << pattern_ << "'"
+ << " against text that is " << text.size() << " bytes.";
+ return 0;
+ case PCRE_ERROR_RECURSIONLIMIT:
+ // See comment about hit_limit above.
+ hit_limit_ = true;
+ PCREPORT(WARNING) << "Exceeded stack limit of " << stack_limit
+ << " when matching '" << pattern_ << "'"
+ << " against text that is " << text.size() << " bytes.";
+ return 0;
+ default:
+ // There are other return codes from pcre.h :
+ // PCRE_ERROR_NULL (-2)
+ // PCRE_ERROR_BADOPTION (-3)
+ // PCRE_ERROR_BADMAGIC (-4)
+ // PCRE_ERROR_UNKNOWN_NODE (-5)
+ // PCRE_ERROR_NOMEMORY (-6)
+ // PCRE_ERROR_NOSUBSTRING (-7)
+ // ...
+ PCREPORT(ERROR) << "Unexpected return code: " << rc
+ << " when matching '" << pattern_ << "'"
+ << ", re=" << re
+ << ", text=" << text
+ << ", vec=" << vec
+ << ", vecsize=" << vecsize;
+ return 0;
+ }
+ }
+
+ return rc;
+}
+
+bool PCRE::DoMatchImpl(const StringPiece& text,
+ Anchor anchor,
+ int* consumed,
+ const Arg* const* args,
+ int n,
+ int* vec,
+ int vecsize) const {
+ assert((1 + n) * 3 <= vecsize); // results + PCRE workspace
+ int matches = TryMatch(text, 0, anchor, true, vec, vecsize);
+ assert(matches >= 0); // TryMatch never returns negatives
+ if (matches == 0)
+ return false;
+
+ *consumed = vec[1];
+
+ if (n == 0 || args == NULL) {
+ // We are not interested in results
+ return true;
+ }
+ if (NumberOfCapturingGroups() < n) {
+ // PCRE has fewer capturing groups than number of arg pointers passed in
+ return false;
+ }
+
+ // If we got here, we must have matched the whole pattern.
+ // We do not need (can not do) any more checks on the value of 'matches' here
+ // -- see the comment for TryMatch.
+ for (int i = 0; i < n; i++) {
+ const int start = vec[2*(i+1)];
+ const int limit = vec[2*(i+1)+1];
+ if (!args[i]->Parse(text.data() + start, limit-start)) {
+ // TODO: Should we indicate what the error was?
+ return false;
+ }
+ }
+
+ return true;
+}
+
+bool PCRE::DoMatch(const StringPiece& text,
+ Anchor anchor,
+ int* consumed,
+ const Arg* const args[],
+ int n) const {
+ assert(n >= 0);
+ size_t const vecsize = (1 + n) * 3; // results + PCRE workspace
+ // (as for kVecSize)
+ int *vec = new int[vecsize];
+ bool b = DoMatchImpl(text, anchor, consumed, args, n, vec, vecsize);
+ delete[] vec;
+ return b;
+}
+
+bool PCRE::Rewrite(string *out, const StringPiece &rewrite,
+ const StringPiece &text, int *vec, int veclen) const {
+ int number_of_capturing_groups = NumberOfCapturingGroups();
+ for (const char *s = rewrite.data(), *end = s + rewrite.size();
+ s < end; s++) {
+ int c = *s;
+ if (c == '\\') {
+ c = *++s;
+ if (isdigit(c)) {
+ int n = (c - '0');
+ if (n >= veclen) {
+ if (n <= number_of_capturing_groups) {
+ // unmatched optional capturing group. treat
+ // its value as empty string; i.e., nothing to append.
+ } else {
+ PCREPORT(ERROR) << "requested group " << n
+ << " in regexp " << rewrite.data();
+ return false;
+ }
+ }
+ int start = vec[2 * n];
+ if (start >= 0)
+ out->append(text.data() + start, vec[2 * n + 1] - start);
+ } else if (c == '\\') {
+ out->push_back('\\');
+ } else {
+ PCREPORT(ERROR) << "invalid rewrite pattern: " << rewrite.data();
+ return false;
+ }
+ } else {
+ out->push_back(c);
+ }
+ }
+ return true;
+}
+
+bool PCRE::CheckRewriteString(const StringPiece& rewrite, string* error) const {
+ int max_token = -1;
+ for (const char *s = rewrite.data(), *end = s + rewrite.size();
+ s < end; s++) {
+ int c = *s;
+ if (c != '\\') {
+ continue;
+ }
+ if (++s == end) {
+ *error = "Rewrite schema error: '\\' not allowed at end.";
+ return false;
+ }
+ c = *s;
+ if (c == '\\') {
+ continue;
+ }
+ if (!isdigit(c)) {
+ *error = "Rewrite schema error: "
+ "'\\' must be followed by a digit or '\\'.";
+ return false;
+ }
+ int n = (c - '0');
+ if (max_token < n) {
+ max_token = n;
+ }
+ }
+
+ if (max_token > NumberOfCapturingGroups()) {
+ SStringPrintf(error, "Rewrite schema requests %d matches, "
+ "but the regexp only has %d parenthesized subexpressions.",
+ max_token, NumberOfCapturingGroups());
+ return false;
+ }
+ return true;
+}
+
+
+// Return the number of capturing subpatterns, or -1 if the
+// regexp wasn't valid on construction.
+int PCRE::NumberOfCapturingGroups() const {
+ if (re_partial_ == NULL) return -1;
+
+ int result;
+ CHECK(pcre_fullinfo(re_partial_, // The regular expression object
+ NULL, // We did not study the pattern
+ PCRE_INFO_CAPTURECOUNT,
+ &result) == 0);
+ return result;
+}
+
+
+/***** Parsers for various types *****/
+
+bool PCRE::Arg::parse_null(const char* str, int n, void* dest) {
+ // We fail if somebody asked us to store into a non-NULL void* pointer
+ return (dest == NULL);
+}
+
+bool PCRE::Arg::parse_string(const char* str, int n, void* dest) {
+ if (dest == NULL) return true;
+ reinterpret_cast<string*>(dest)->assign(str, n);
+ return true;
+}
+
+bool PCRE::Arg::parse_stringpiece(const char* str, int n, void* dest) {
+ if (dest == NULL) return true;
+ reinterpret_cast<StringPiece*>(dest)->set(str, n);
+ return true;
+}
+
+bool PCRE::Arg::parse_char(const char* str, int n, void* dest) {
+ if (n != 1) return false;
+ if (dest == NULL) return true;
+ *(reinterpret_cast<char*>(dest)) = str[0];
+ return true;
+}
+
+bool PCRE::Arg::parse_uchar(const char* str, int n, void* dest) {
+ if (n != 1) return false;
+ if (dest == NULL) return true;
+ *(reinterpret_cast<unsigned char*>(dest)) = str[0];
+ return true;
+}
+
+// Largest number spec that we are willing to parse
+static const int kMaxNumberLength = 32;
+
+// PCREQUIPCRES "buf" must have length at least kMaxNumberLength+1
+// PCREQUIPCRES "n > 0"
+// Copies "str" into "buf" and null-terminates if necessary.
+// Returns one of:
+// a. "str" if no termination is needed
+// b. "buf" if the string was copied and null-terminated
+// c. "" if the input was invalid and has no hope of being parsed
+static const char* TerminateNumber(char* buf, const char* str, int n) {
+ if ((n > 0) && isspace(*str)) {
+ // We are less forgiving than the strtoxxx() routines and do not
+ // allow leading spaces.
+ return "";
+ }
+
+ // See if the character right after the input text may potentially
+ // look like a digit.
+ if (isdigit(str[n]) ||
+ ((str[n] >= 'a') && (str[n] <= 'f')) ||
+ ((str[n] >= 'A') && (str[n] <= 'F'))) {
+ if (n > kMaxNumberLength) return ""; // Input too big to be a valid number
+ memcpy(buf, str, n);
+ buf[n] = '\0';
+ return buf;
+ } else {
+ // We can parse right out of the supplied string, so return it.
+ return str;
+ }
+}
+
+bool PCRE::Arg::parse_long_radix(const char* str,
+ int n,
+ void* dest,
+ int radix) {
+ if (n == 0) return false;
+ char buf[kMaxNumberLength+1];
+ str = TerminateNumber(buf, str, n);
+ char* end;
+ errno = 0;
+ long r = strtol(str, &end, radix);
+ if (end != str + n) return false; // Leftover junk
+ if (errno) return false;
+ if (dest == NULL) return true;
+ *(reinterpret_cast<long*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_ulong_radix(const char* str,
+ int n,
+ void* dest,
+ int radix) {
+ if (n == 0) return false;
+ char buf[kMaxNumberLength+1];
+ str = TerminateNumber(buf, str, n);
+ if (str[0] == '-') {
+ // strtoul() will silently accept negative numbers and parse
+ // them. This module is more strict and treats them as errors.
+ return false;
+ }
+
+ char* end;
+ errno = 0;
+ unsigned long r = strtoul(str, &end, radix);
+ if (end != str + n) return false; // Leftover junk
+ if (errno) return false;
+ if (dest == NULL) return true;
+ *(reinterpret_cast<unsigned long*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_short_radix(const char* str,
+ int n,
+ void* dest,
+ int radix) {
+ long r;
+ if (!parse_long_radix(str, n, &r, radix)) return false; // Could not parse
+ if ((short)r != r) return false; // Out of range
+ if (dest == NULL) return true;
+ *(reinterpret_cast<short*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_ushort_radix(const char* str,
+ int n,
+ void* dest,
+ int radix) {
+ unsigned long r;
+ if (!parse_ulong_radix(str, n, &r, radix)) return false; // Could not parse
+ if ((ushort)r != r) return false; // Out of range
+ if (dest == NULL) return true;
+ *(reinterpret_cast<unsigned short*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_int_radix(const char* str,
+ int n,
+ void* dest,
+ int radix) {
+ long r;
+ if (!parse_long_radix(str, n, &r, radix)) return false; // Could not parse
+ if ((int)r != r) return false; // Out of range
+ if (dest == NULL) return true;
+ *(reinterpret_cast<int*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_uint_radix(const char* str,
+ int n,
+ void* dest,
+ int radix) {
+ unsigned long r;
+ if (!parse_ulong_radix(str, n, &r, radix)) return false; // Could not parse
+ if ((uint)r != r) return false; // Out of range
+ if (dest == NULL) return true;
+ *(reinterpret_cast<unsigned int*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_longlong_radix(const char* str,
+ int n,
+ void* dest,
+ int radix) {
+ if (n == 0) return false;
+ char buf[kMaxNumberLength+1];
+ str = TerminateNumber(buf, str, n);
+ char* end;
+ errno = 0;
+ int64 r = strtoll(str, &end, radix);
+ if (end != str + n) return false; // Leftover junk
+ if (errno) return false;
+ if (dest == NULL) return true;
+ *(reinterpret_cast<int64*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_ulonglong_radix(const char* str,
+ int n,
+ void* dest,
+ int radix) {
+ if (n == 0) return false;
+ char buf[kMaxNumberLength+1];
+ str = TerminateNumber(buf, str, n);
+ if (str[0] == '-') {
+ // strtoull() will silently accept negative numbers and parse
+ // them. This module is more strict and treats them as errors.
+ return false;
+ }
+ char* end;
+ errno = 0;
+ uint64 r = strtoull(str, &end, radix);
+ if (end != str + n) return false; // Leftover junk
+ if (errno) return false;
+ if (dest == NULL) return true;
+ *(reinterpret_cast<uint64*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_double(const char* str, int n, void* dest) {
+ if (n == 0) return false;
+ static const int kMaxLength = 200;
+ char buf[kMaxLength];
+ if (n >= kMaxLength) return false;
+ memcpy(buf, str, n);
+ buf[n] = '\0';
+ errno = 0;
+ char* end;
+ double r = strtod(buf, &end);
+ if (end != buf + n) {
+#ifdef COMPILER_MSVC
+ // Microsoft's strtod() doesn't handle inf and nan, so we have to
+ // handle it explicitly. Speed is not important here because this
+ // code is only called in unit tests.
+ bool pos = true;
+ const char* i = buf;
+ if ('-' == *i) {
+ pos = false;
+ ++i;
+ } else if ('+' == *i) {
+ ++i;
+ }
+ if (0 == stricmp(i, "inf") || 0 == stricmp(i, "infinity")) {
+ r = numeric_limits<double>::infinity();
+ if (!pos)
+ r = -r;
+ } else if (0 == stricmp(i, "nan")) {
+ r = numeric_limits<double>::quiet_NaN();
+ } else {
+ return false;
+ }
+#else
+ return false; // Leftover junk
+#endif
+ }
+ if (errno) return false;
+ if (dest == NULL) return true;
+ *(reinterpret_cast<double*>(dest)) = r;
+ return true;
+}
+
+bool PCRE::Arg::parse_float(const char* str, int n, void* dest) {
+ double r;
+ if (!parse_double(str, n, &r)) return false;
+ if (dest == NULL) return true;
+ *(reinterpret_cast<float*>(dest)) = static_cast<float>(r);
+ return true;
+}
+
+
+#define DEFINE_INTEGER_PARSERS(name) \
+ bool PCRE::Arg::parse_##name(const char* str, int n, void* dest) { \
+ return parse_##name##_radix(str, n, dest, 10); \
+ } \
+ bool PCRE::Arg::parse_##name##_hex(const char* str, int n, void* dest) { \
+ return parse_##name##_radix(str, n, dest, 16); \
+ } \
+ bool PCRE::Arg::parse_##name##_octal(const char* str, int n, void* dest) { \
+ return parse_##name##_radix(str, n, dest, 8); \
+ } \
+ bool PCRE::Arg::parse_##name##_cradix(const char* str, int n, void* dest) { \
+ return parse_##name##_radix(str, n, dest, 0); \
+ }
+
+DEFINE_INTEGER_PARSERS(short);
+DEFINE_INTEGER_PARSERS(ushort);
+DEFINE_INTEGER_PARSERS(int);
+DEFINE_INTEGER_PARSERS(uint);
+DEFINE_INTEGER_PARSERS(long);
+DEFINE_INTEGER_PARSERS(ulong);
+DEFINE_INTEGER_PARSERS(longlong);
+DEFINE_INTEGER_PARSERS(ulonglong);
+
+#undef DEFINE_INTEGER_PARSERS
+
+} // namespace re2
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