text: //===-- sanitizer_common.cpp ----------------------------------------------===//
  //
  // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
  // See https://llvm.org/LICENSE.txt for license information.
  // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
  //
  //===----------------------------------------------------------------------===//
  //
  // This file is shared between AddressSanitizer and ThreadSanitizer
  // run-time libraries.
  //===----------------------------------------------------------------------===//
  
  #include "sanitizer_common.h"
  
  #include "sanitizer_allocator_interface.h"
  #include "sanitizer_allocator_internal.h"
  #include "sanitizer_atomic.h"
  #include "sanitizer_flags.h"
  #include "sanitizer_interface_internal.h"
  #include "sanitizer_libc.h"
  #include "sanitizer_placement_new.h"
  
  namespace __sanitizer {
  
  const char *SanitizerToolName = "SanitizerTool";
  
  atomic_uint32_t current_verbosity;
  uptr PageSizeCached;
  u32 NumberOfCPUsCached;
  
  // PID of the tracer task in StopTheWorld. It shares the address space with the
  // main process, but has a different PID and thus requires special handling.
  uptr stoptheworld_tracer_pid = 0;
  // Cached pid of parent process - if the parent process dies, we want to keep
  // writing to the same log file.
  uptr stoptheworld_tracer_ppid = 0;
  
  void NORETURN ReportMmapFailureAndDie(uptr size, const char *mem_type,
                                        const char *mmap_type, error_t err,
                                        bool raw_report) {
    static int recursion_count;
    if (raw_report || recursion_count) {
      // If raw report is requested or we went into recursion just die.  The
      // Report() and CHECK calls below may call mmap recursively and fail.
      RawWrite("ERROR: Failed to mmap\n");
      Die();
    }
    recursion_count++;
    Report("ERROR: %s failed to "
           "%s 0x%zx (%zd) bytes of %s (error code: %d)\n",
           SanitizerToolName, mmap_type, size, size, mem_type, err);
  #if !SANITIZER_GO
    DumpProcessMap();
  #endif
    UNREACHABLE("unable to mmap");
  }
  
  typedef bool UptrComparisonFunction(const uptr &a, const uptr &b);
  typedef bool U32ComparisonFunction(const u32 &a, const u32 &b);
  
  const char *StripPathPrefix(const char *filepath,
                              const char *strip_path_prefix) {
    if (!filepath) return nullptr;
    if (!strip_path_prefix) return filepath;
    const char *res = filepath;
    if (const char *pos = internal_strstr(filepath, strip_path_prefix))
      res = pos + internal_strlen(strip_path_prefix);
    if (res[0] == '.' && res[1] == '/')
      res += 2;
    return res;
  }
  
  const char *StripModuleName(const char *module) {
    if (!module)
      return nullptr;
    if (SANITIZER_WINDOWS) {
      // On Windows, both slash and backslash are possible.
      // Pick the one that goes last.
      if (const char *bslash_pos = internal_strrchr(module, '\\'))
        return StripModuleName(bslash_pos + 1);
    }
    if (const char *slash_pos = internal_strrchr(module, '/')) {
      return slash_pos + 1;
    }
    return module;
  }
  
  void ReportErrorSummary(const char *error_message, const char *alt_tool_name) {
    if (!common_flags()->print_summary)
      return;
    InternalScopedString buff;
    buff.append("SUMMARY: %s: %s",
                alt_tool_name ? alt_tool_name : SanitizerToolName, error_message);
    __sanitizer_report_error_summary(buff.data());
  }
  
  // Removes the ANSI escape sequences from the input string (in-place).
  void RemoveANSIEscapeSequencesFromString(char *str) {
    if (!str)
      return;
  
    // We are going to remove the escape sequences in place.
    char *s = str;
    char *z = str;
    while (*s != '\0') {
      CHECK_GE(s, z);
      // Skip over ANSI escape sequences with pointer 's'.
      if (*s == '\033' && *(s + 1) == '[') {
        s = internal_strchrnul(s, 'm');
        if (*s == '\0') {
          break;
        }
        s++;
        continue;
      }
      // 's' now points at a character we want to keep. Copy over the buffer
      // content if the escape sequence has been perviously skipped andadvance
      // both pointers.
      if (s != z)
        *z = *s;
  
      // If we have not seen an escape sequence, just advance both pointers.
      z++;
      s++;
    }
  
    // Null terminate the string.
    *z = '\0';
  }
  
  void LoadedModule::set(const char *module_name, uptr base_address,
                         bool instrumented) {
    clear();
    full_name_ = internal_strdup(module_name);
    base_address_ = base_address;
    instrumented_ = instrumented;
  }
  
  void LoadedModule::set(const char *module_name, uptr base_address,
                         ModuleArch arch, u8 uuid[kModuleUUIDSize],
                         bool instrumented) {
    set(module_name, base_address, instrumented);
    arch_ = arch;
    internal_memcpy(uuid_, uuid, sizeof(uuid_));
    uuid_size_ = kModuleUUIDSize;
  }
  
  void LoadedModule::setUuid(const char *uuid, uptr size) {
    if (size > kModuleUUIDSize)
      size = kModuleUUIDSize;
    internal_memcpy(uuid_, uuid, size);
    uuid_size_ = size;
  }
  
  void LoadedModule::clear() {
    InternalFree(full_name_);
    base_address_ = 0;
    max_address_ = 0;
    full_name_ = nullptr;
    arch_ = kModuleArchUnknown;
    internal_memset(uuid_, 0, kModuleUUIDSize);
    instrumented_ = false;
    while (!ranges_.empty()) {
      AddressRange *r = ranges_.front();
      ranges_.pop_front();
      InternalFree(r);
    }
  }
  
  void LoadedModule::addAddressRange(uptr beg, uptr end, bool executable,
                                     bool writable, const char *name) {
    void *mem = InternalAlloc(sizeof(AddressRange));
    AddressRange *r =
        new(mem) AddressRange(beg, end, executable, writable, name);
    ranges_.push_back(r);
    max_address_ = Max(max_address_, end);
  }
  
  bool LoadedModule::containsAddress(uptr address) const {
    for (const AddressRange &r : ranges()) {
      if (r.beg <= address && address < r.end)
        return true;
    }
    return false;
  }
  
  static atomic_uintptr_t g_total_mmaped;
  
  void IncreaseTotalMmap(uptr size) {
    if (!common_flags()->mmap_limit_mb) return;
    uptr total_mmaped =
        atomic_fetch_add(&g_total_mmaped, size, memory_order_relaxed) + size;
    // Since for now mmap_limit_mb is not a user-facing flag, just kill
    // a program. Use RAW_CHECK to avoid extra mmaps in reporting.
    RAW_CHECK((total_mmaped >> 20) < common_flags()->mmap_limit_mb);
  }
  
  void DecreaseTotalMmap(uptr size) {
    if (!common_flags()->mmap_limit_mb) return;
    atomic_fetch_sub(&g_total_mmaped, size, memory_order_relaxed);
  }
  
  bool TemplateMatch(const char *templ, const char *str) {
    if ((!str) || str[0] == 0)
      return false;
    bool start = false;
    if (templ && templ[0] == '^') {
      start = true;
      templ++;
    }
    bool asterisk = false;
    while (templ && templ[0]) {
      if (templ[0] == '*') {
        templ++;
        start = false;
        asterisk = true;
        continue;
      }
      if (templ[0] == '$')
        return str[0] == 0 || asterisk;
      if (str[0] == 0)
        return false;
      char *tpos = (char*)internal_strchr(templ, '*');
      char *tpos1 = (char*)internal_strchr(templ, '$');
      if ((!tpos) || (tpos1 && tpos1 < tpos))
        tpos = tpos1;
      if (tpos)
        tpos[0] = 0;
      const char *str0 = str;
      const char *spos = internal_strstr(str, templ);
      str = spos + internal_strlen(templ);
      templ = tpos;
      if (tpos)
        tpos[0] = tpos == tpos1 ? '$' : '*';
      if (!spos)
        return false;
      if (start && spos != str0)
        return false;
      start = false;
      asterisk = false;
    }
    return true;
  }
  
  static char binary_name_cache_str[kMaxPathLength];
  static char process_name_cache_str[kMaxPathLength];
  
  const char *GetProcessName() {
    return process_name_cache_str;
  }
  
  static uptr ReadProcessName(/*out*/ char *buf, uptr buf_len) {
    ReadLongProcessName(buf, buf_len);
    char *s = const_cast<char *>(StripModuleName(buf));
    uptr len = internal_strlen(s);
    if (s != buf) {
      internal_memmove(buf, s, len);
      buf[len] = '\0';
    }
    return len;
  }
  
  void UpdateProcessName() {
    ReadProcessName(process_name_cache_str, sizeof(process_name_cache_str));
  }
  
  // Call once to make sure that binary_name_cache_str is initialized
  void CacheBinaryName() {
    if (binary_name_cache_str[0] != '\0')
      return;
    ReadBinaryName(binary_name_cache_str, sizeof(binary_name_cache_str));
    ReadProcessName(process_name_cache_str, sizeof(process_name_cache_str));
  }
  
  uptr ReadBinaryNameCached(/*out*/char *buf, uptr buf_len) {
    CacheBinaryName();
    uptr name_len = internal_strlen(binary_name_cache_str);
    name_len = (name_len < buf_len - 1) ? name_len : buf_len - 1;
    if (buf_len == 0)
      return 0;
    internal_memcpy(buf, binary_name_cache_str, name_len);
    buf[name_len] = '\0';
    return name_len;
  }
  
  uptr ReadBinaryDir(/*out*/ char *buf, uptr buf_len) {
    ReadBinaryNameCached(buf, buf_len);
    const char *exec_name_pos = StripModuleName(buf);
    uptr name_len = exec_name_pos - buf;
    buf[name_len] = '\0';
    return name_len;
  }
  
  #if !SANITIZER_GO
  void PrintCmdline() {
    char **argv = GetArgv();
    if (!argv) return;
    Printf("\nCommand: ");
    for (uptr i = 0; argv[i]; ++i)
      Printf("%s ", argv[i]);
    Printf("\n\n");
  }
  #endif
  
  // Malloc hooks.
  static const int kMaxMallocFreeHooks = 5;
  struct MallocFreeHook {
    void (*malloc_hook)(const void *, uptr);
    void (*free_hook)(const void *);
  };
  
  static MallocFreeHook MFHooks[kMaxMallocFreeHooks];
  
  void RunMallocHooks(void *ptr, uptr size) {
    __sanitizer_malloc_hook(ptr, size);
    for (int i = 0; i < kMaxMallocFreeHooks; i++) {
      auto hook = MFHooks[i].malloc_hook;
      if (!hook)
        break;
      hook(ptr, size);
    }
  }
  
  void RunFreeHooks(void *ptr) {
    __sanitizer_free_hook(ptr);
    for (int i = 0; i < kMaxMallocFreeHooks; i++) {
      auto hook = MFHooks[i].free_hook;
      if (!hook)
        break;
      hook(ptr);
    }
  }
  
  static int InstallMallocFreeHooks(void (*malloc_hook)(const void *, uptr),
                                    void (*free_hook)(const void *)) {
    if (!malloc_hook || !free_hook) return 0;
    for (int i = 0; i < kMaxMallocFreeHooks; i++) {
      if (MFHooks[i].malloc_hook == nullptr) {
        MFHooks[i].malloc_hook = malloc_hook;
        MFHooks[i].free_hook = free_hook;
        return i + 1;
      }
    }
    return 0;
  }
  
  void internal_sleep(unsigned seconds) {
    internal_usleep((u64)seconds * 1000 * 1000);
  }
  void SleepForSeconds(unsigned seconds) {
    internal_usleep((u64)seconds * 1000 * 1000);
  }
  void SleepForMillis(unsigned millis) { internal_usleep((u64)millis * 1000); }
  
  } // namespace __sanitizer
  
  using namespace __sanitizer;
  
  extern "C" {
  SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_report_error_summary,
                               const char *error_summary) {
    Printf("%s\n", error_summary);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  int __sanitizer_acquire_crash_state() {
    static atomic_uint8_t in_crash_state = {};
    return !atomic_exchange(&in_crash_state, 1, memory_order_relaxed);
  }
  
  SANITIZER_INTERFACE_ATTRIBUTE
  int __sanitizer_install_malloc_and_free_hooks(void (*malloc_hook)(const void *,
                                                                    uptr),
                                                void (*free_hook)(const void *)) {
    return InstallMallocFreeHooks(malloc_hook, free_hook);
  }
  
  // Provide default (no-op) implementation of malloc hooks.
  SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_malloc_hook, void *ptr,
                               uptr size) {
    (void)ptr;
    (void)size;
  }
  
  SANITIZER_INTERFACE_WEAK_DEF(void, __sanitizer_free_hook, void *ptr) {
    (void)ptr;
  }
  
  } // extern "C"
  