libsanitizer/sanitizer_common/sanitizer_flag_parser.cc

   1 //===-- sanitizer_flag_parser.cc ------------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is a part of ThreadSanitizer/AddressSanitizer runtime.
   9 //
  10 //===----------------------------------------------------------------------===//
  11
  12 #include "sanitizer_flag_parser.h"
  13
  14 #include "sanitizer_common.h"
  15 #include "sanitizer_libc.h"
  16 #include "sanitizer_flags.h"
  17 #include "sanitizer_flag_parser.h"
  18
  19 namespace __sanitizer {
  20
  21 LowLevelAllocator FlagParser::Alloc;
  22
  23 class UnknownFlags {
  24   static const int kMaxUnknownFlags = 20;
  25   const char *unknown_flags_[kMaxUnknownFlags];
  26   int n_unknown_flags_;
  27
  28  public:
  29   void Add(const char *name) {
  30     CHECK_LT(n_unknown_flags_, kMaxUnknownFlags);
  31     unknown_flags_[n_unknown_flags_++] = name;
  32   }
  33
  34   void Report() {
  35     if (!n_unknown_flags_) return;
  36     Printf("WARNING: found %d unrecognized flag(s):\n", n_unknown_flags_);
  37     for (int i = 0; i < n_unknown_flags_; ++i)
  38       Printf("    %s\n", unknown_flags_[i]);
  39     n_unknown_flags_ = 0;
  40   }
  41 };
  42
  43 UnknownFlags unknown_flags;
  44
  45 void ReportUnrecognizedFlags() {
  46   unknown_flags.Report();
  47 }
  48
  49 char *FlagParser::ll_strndup(const char *s, uptr n) {
  50   uptr len = internal_strnlen(s, n);
  51   char *s2 = (char*)Alloc.Allocate(len + 1);
  52   internal_memcpy(s2, s, len);
  53   s2[len] = 0;
  54   return s2;
  55 }
  56
  57 void FlagParser::PrintFlagDescriptions() {
  58   Printf("Available flags for %s:\n", SanitizerToolName);
  59   for (int i = 0; i < n_flags_; ++i)
  60     Printf("\t%s\n\t\t- %s\n", flags_[i].name, flags_[i].desc);
  61 }
  62
  63 void FlagParser::fatal_error(const char *err) {
  64   Printf("ERROR: %s\n", err);
  65   Die();
  66 }
  67
  68 bool FlagParser::is_space(char c) {
  69   return c == ' ' || c == ',' || c == ':' || c == '\n' || c == '\t' ||
  70          c == '\r';
  71 }
  72
  73 void FlagParser::skip_whitespace() {
  74   while (is_space(buf_[pos_])) ++pos_;
  75 }
  76
  77 void FlagParser::parse_flag() {
  78   uptr name_start = pos_;
  79   while (buf_[pos_] != 0 && buf_[pos_] != '=' && !is_space(buf_[pos_])) ++pos_;
  80   if (buf_[pos_] != '=') fatal_error("expected '='");
  81   char *name = ll_strndup(buf_ + name_start, pos_ - name_start);
  82
  83   uptr value_start = ++pos_;
  84   char *value;
  85   if (buf_[pos_] == '\'' || buf_[pos_] == '"') {
  86     char quote = buf_[pos_++];
  87     while (buf_[pos_] != 0 && buf_[pos_] != quote) ++pos_;
  88     if (buf_[pos_] == 0) fatal_error("unterminated string");
  89     value = ll_strndup(buf_ + value_start + 1, pos_ - value_start - 1);
  90     ++pos_; // consume the closing quote
  91   } else {
  92     while (buf_[pos_] != 0 && !is_space(buf_[pos_])) ++pos_;
  93     if (buf_[pos_] != 0 && !is_space(buf_[pos_]))
  94       fatal_error("expected separator or eol");
  95     value = ll_strndup(buf_ + value_start, pos_ - value_start);
  96   }
  97
  98   bool res = run_handler(name, value);
  99   if (!res) fatal_error("Flag parsing failed.");
 100 }
 101
 102 void FlagParser::parse_flags() {
 103   while (true) {
 104     skip_whitespace();
 105     if (buf_[pos_] == 0) break;
 106     parse_flag();
 107   }
 108
 109   // Do a sanity check for certain flags.
 110   if (common_flags_dont_use.malloc_context_size < 1)
 111     common_flags_dont_use.malloc_context_size = 1;
 112 }
 113
 114 void FlagParser::ParseString(const char *s) {
 115   if (!s) return;
 116   // Backup current parser state to allow nested ParseString() calls.
 117   const char *old_buf_ = buf_;
 118   uptr old_pos_ = pos_;
 119   buf_ = s;
 120   pos_ = 0;
 121
 122   parse_flags();
 123
 124   buf_ = old_buf_;
 125   pos_ = old_pos_;
 126 }
 127
 128 bool FlagParser::ParseFile(const char *path, bool ignore_missing) {
 129   static const uptr kMaxIncludeSize = 1 << 15;
 130   char *data;
 131   uptr data_mapped_size;
 132   error_t err;
 133   uptr len;
 134   if (!ReadFileToBuffer(path, &data, &data_mapped_size, &len,
 135                         Max(kMaxIncludeSize, GetPageSizeCached()), &err)) {
 136     if (ignore_missing)
 137       return true;
 138     Printf("Failed to read options from '%s': error %d\n", path, err);
 139     return false;
 140   }
 141   ParseString(data);
 142   UnmapOrDie(data, data_mapped_size);
 143   return true;
 144 }
 145
 146 bool FlagParser::run_handler(const char *name, const char *value) {
 147   for (int i = 0; i < n_flags_; ++i) {
 148     if (internal_strcmp(name, flags_[i].name) == 0)
 149       return flags_[i].handler->Parse(value);
 150   }
 151   // Unrecognized flag. This is not a fatal error, we may print a warning later.
 152   unknown_flags.Add(name);
 153   return true;
 154 }
 155
 156 void FlagParser::RegisterHandler(const char *name, FlagHandlerBase *handler,
 157                                  const char *desc) {
 158   CHECK_LT(n_flags_, kMaxFlags);
 159   flags_[n_flags_].name = name;
 160   flags_[n_flags_].desc = desc;
 161   flags_[n_flags_].handler = handler;
 162   ++n_flags_;
 163 }
 164
 165 FlagParser::FlagParser() : n_flags_(0), buf_(nullptr), pos_(0) {
 166   flags_ = (Flag *)Alloc.Allocate(sizeof(Flag) * kMaxFlags);
 167 }
 168
 169 }  // namespace __sanitizer