libasan/sanitizer_common/sanitizer_flags.cc

   1 //===-- sanitizer_flags.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_flags.h"
  13
  14 #include "sanitizer_common.h"
  15 #include "sanitizer_libc.h"
  16
  17 namespace __sanitizer {
  18
  19 static bool GetFlagValue(const char *env, const char *name,
  20                          const char **value, int *value_length) {
  21   if (env == 0)
  22     return false;
  23   const char *pos = internal_strstr(env, name);
  24   const char *end;
  25   if (pos == 0)
  26     return false;
  27   pos += internal_strlen(name);
  28   if (pos[0] != '=') {
  29     end = pos;
  30   } else {
  31     pos += 1;
  32     if (pos[0] == '"') {
  33       pos += 1;
  34       end = internal_strchr(pos, '"');
  35     } else if (pos[0] == '\'') {
  36       pos += 1;
  37       end = internal_strchr(pos, '\'');
  38     } else {
  39       end = internal_strchr(pos, ' ');
  40     }
  41     if (end == 0)
  42       end = pos + internal_strlen(pos);
  43   }
  44   *value = pos;
  45   *value_length = end - pos;
  46   return true;
  47 }
  48
  49 static bool StartsWith(const char *flag, int flag_length, const char *value) {
  50   if (!flag || !value)
  51     return false;
  52   int value_length = internal_strlen(value);
  53   return (flag_length >= value_length) &&
  54          (0 == internal_strncmp(flag, value, value_length));
  55 }
  56
  57 void ParseFlag(const char *env, bool *flag, const char *name) {
  58   const char *value;
  59   int value_length;
  60   if (!GetFlagValue(env, name, &value, &value_length))
  61     return;
  62   if (StartsWith(value, value_length, "0") ||
  63       StartsWith(value, value_length, "no") ||
  64       StartsWith(value, value_length, "false"))
  65     *flag = false;
  66   if (StartsWith(value, value_length, "1") ||
  67       StartsWith(value, value_length, "yes") ||
  68       StartsWith(value, value_length, "true"))
  69     *flag = true;
  70 }
  71
  72 void ParseFlag(const char *env, int *flag, const char *name) {
  73   const char *value;
  74   int value_length;
  75   if (!GetFlagValue(env, name, &value, &value_length))
  76     return;
  77   *flag = internal_atoll(value);
  78 }
  79
  80 static LowLevelAllocator allocator_for_flags;
  81
  82 void ParseFlag(const char *env, const char **flag, const char *name) {
  83   const char *value;
  84   int value_length;
  85   if (!GetFlagValue(env, name, &value, &value_length))
  86     return;
  87   // Copy the flag value. Don't use locks here, as flags are parsed at
  88   // tool startup.
  89   char *value_copy = (char*)(allocator_for_flags.Allocate(value_length + 1));
  90   internal_memcpy(value_copy, value, value_length);
  91   value_copy[value_length] = '\0';
  92   *flag = value_copy;
  93 }
  94
  95 }  // namespace __sanitizer