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Diffstat (limited to 'util/pcre.cc')
| -rw-r--r-- | util/pcre.cc | 961 |
1 files changed, 961 insertions, 0 deletions
diff --git a/util/pcre.cc b/util/pcre.cc new file mode 100644 index 0000000..5e67e1f --- /dev/null +++ b/util/pcre.cc @@ -0,0 +1,961 @@ +// 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 |