compiler-rt/lib/sanitizer_common/sanitizer_file.cpp

   1 //===-- sanitizer_file.cpp -----------------------------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===---------------------------------------------------------------------===//
   8 //
   9 // This file is shared between AddressSanitizer and ThreadSanitizer
  10 // run-time libraries.  It defines filesystem-related interfaces.  This
  11 // is separate from sanitizer_common.cpp so that it's simpler to disable
  12 // all the filesystem support code for a port that doesn't use it.
  13 //
  14 //===---------------------------------------------------------------------===//
  15
  16 #include "sanitizer_platform.h"
  17
  18 #if !SANITIZER_FUCHSIA
  19
  20 #include "sanitizer_common.h"
  21 #include "sanitizer_file.h"
  22 #  include "sanitizer_interface_internal.h"
  23
  24 namespace __sanitizer {
  25
  26 void CatastrophicErrorWrite(const char *buffer, uptr length) {
  27   WriteToFile(kStderrFd, buffer, length);
  28 }
  29
  30 StaticSpinMutex report_file_mu;
  31 ReportFile report_file = {&report_file_mu, kStderrFd, "", "", 0};
  32
  33 void RawWrite(const char *buffer) {
  34   report_file.Write(buffer, internal_strlen(buffer));
  35 }
  36
  37 void ReportFile::ReopenIfNecessary() {
  38   mu->CheckLocked();
  39   if (fd == kStdoutFd || fd == kStderrFd) return;
  40
  41   uptr pid = internal_getpid();
  42   // If in tracer, use the parent's file.
  43   if (pid == stoptheworld_tracer_pid)
  44     pid = stoptheworld_tracer_ppid;
  45   if (fd != kInvalidFd) {
  46     // If the report file is already opened by the current process,
  47     // do nothing. Otherwise the report file was opened by the parent
  48     // process, close it now.
  49     if (fd_pid == pid)
  50       return;
  51     else
  52       CloseFile(fd);
  53   }
  54
  55   const char *exe_name = GetProcessName();
  56   if (common_flags()->log_exe_name && exe_name) {
  57     internal_snprintf(full_path, kMaxPathLength, "%s.%s.%zu", path_prefix,
  58                       exe_name, pid);
  59   } else {
  60     internal_snprintf(full_path, kMaxPathLength, "%s.%zu", path_prefix, pid);
  61   }
  62   if (common_flags()->log_suffix) {
  63     internal_strlcat(full_path, common_flags()->log_suffix, kMaxPathLength);
  64   }
  65   error_t err;
  66   fd = OpenFile(full_path, WrOnly, &err);
  67   if (fd == kInvalidFd) {
  68     const char *ErrorMsgPrefix = "ERROR: Can't open file: ";
  69     WriteToFile(kStderrFd, ErrorMsgPrefix, internal_strlen(ErrorMsgPrefix));
  70     WriteToFile(kStderrFd, full_path, internal_strlen(full_path));
  71     char errmsg[100];
  72     internal_snprintf(errmsg, sizeof(errmsg), " (reason: %d)", err);
  73     WriteToFile(kStderrFd, errmsg, internal_strlen(errmsg));
  74     Die();
  75   }
  76   fd_pid = pid;
  77 }
  78
  79 static void RecursiveCreateParentDirs(char *path) {
  80   if (path[0] == '\0')
  81     return;
  82   for (int i = 1; path[i] != '\0'; ++i) {
  83     char save = path[i];
  84     if (!IsPathSeparator(path[i]))
  85       continue;
  86     path[i] = '\0';
  87     if (!DirExists(path) && !CreateDir(path)) {
  88       const char *ErrorMsgPrefix = "ERROR: Can't create directory: ";
  89       WriteToFile(kStderrFd, ErrorMsgPrefix, internal_strlen(ErrorMsgPrefix));
  90       WriteToFile(kStderrFd, path, internal_strlen(path));
  91       Die();
  92     }
  93     path[i] = save;
  94   }
  95 }
  96
  97 void ReportFile::SetReportPath(const char *path) {
  98   if (path) {
  99     uptr len = internal_strlen(path);
 100     if (len > sizeof(path_prefix) - 100) {
 101       Report("ERROR: Path is too long: %c%c%c%c%c%c%c%c...\n", path[0], path[1],
 102              path[2], path[3], path[4], path[5], path[6], path[7]);
 103       Die();
 104     }
 105   }
 106
 107   SpinMutexLock l(mu);
 108   if (fd != kStdoutFd && fd != kStderrFd && fd != kInvalidFd)
 109     CloseFile(fd);
 110   fd = kInvalidFd;
 111   if (!path || internal_strcmp(path, "stderr") == 0) {
 112     fd = kStderrFd;
 113   } else if (internal_strcmp(path, "stdout") == 0) {
 114     fd = kStdoutFd;
 115   } else {
 116     internal_snprintf(path_prefix, kMaxPathLength, "%s", path);
 117     RecursiveCreateParentDirs(path_prefix);
 118   }
 119 }
 120
 121 const char *ReportFile::GetReportPath() {
 122   SpinMutexLock l(mu);
 123   ReopenIfNecessary();
 124   return full_path;
 125 }
 126
 127 bool ReadFileToBuffer(const char *file_name, char **buff, uptr *buff_size,
 128                       uptr *read_len, uptr max_len, error_t *errno_p) {
 129   *buff = nullptr;
 130   *buff_size = 0;
 131   *read_len = 0;
 132   if (!max_len)
 133     return true;
 134   uptr PageSize = GetPageSizeCached();
 135   uptr kMinFileLen = Min(PageSize, max_len);
 136
 137   // The files we usually open are not seekable, so try different buffer sizes.
 138   for (uptr size = kMinFileLen;; size = Min(size * 2, max_len)) {
 139     UnmapOrDie(*buff, *buff_size);
 140     *buff = (char*)MmapOrDie(size, __func__);
 141     *buff_size = size;
 142     fd_t fd = OpenFile(file_name, RdOnly, errno_p);
 143     if (fd == kInvalidFd) {
 144       UnmapOrDie(*buff, *buff_size);
 145       return false;
 146     }
 147     *read_len = 0;
 148     // Read up to one page at a time.
 149     bool reached_eof = false;
 150     while (*read_len < size) {
 151       uptr just_read;
 152       if (!ReadFromFile(fd, *buff + *read_len, size - *read_len, &just_read,
 153                         errno_p)) {
 154         UnmapOrDie(*buff, *buff_size);
 155         CloseFile(fd);
 156         return false;
 157       }
 158       *read_len += just_read;
 159       if (just_read == 0 || *read_len == max_len) {
 160         reached_eof = true;
 161         break;
 162       }
 163     }
 164     CloseFile(fd);
 165     if (reached_eof)  // We've read the whole file.
 166       break;
 167   }
 168   return true;
 169 }
 170
 171 bool ReadFileToVector(const char *file_name,
 172                       InternalMmapVectorNoCtor<char> *buff, uptr max_len,
 173                       error_t *errno_p) {
 174   buff->clear();
 175   if (!max_len)
 176     return true;
 177   uptr PageSize = GetPageSizeCached();
 178   fd_t fd = OpenFile(file_name, RdOnly, errno_p);
 179   if (fd == kInvalidFd)
 180     return false;
 181   uptr read_len = 0;
 182   while (read_len < max_len) {
 183     if (read_len >= buff->size())
 184       buff->resize(Min(Max(PageSize, read_len * 2), max_len));
 185     CHECK_LT(read_len, buff->size());
 186     CHECK_LE(buff->size(), max_len);
 187     uptr just_read;
 188     if (!ReadFromFile(fd, buff->data() + read_len, buff->size() - read_len,
 189                       &just_read, errno_p)) {
 190       CloseFile(fd);
 191       return false;
 192     }
 193     read_len += just_read;
 194     if (!just_read)
 195       break;
 196   }
 197   CloseFile(fd);
 198   buff->resize(read_len);
 199   return true;
 200 }
 201
 202 static const char kPathSeparator = SANITIZER_WINDOWS ? ';' : ':';
 203
 204 char *FindPathToBinary(const char *name) {
 205   if (FileExists(name)) {
 206     return internal_strdup(name);
 207   }
 208
 209   const char *path = GetEnv("PATH");
 210   if (!path)
 211     return nullptr;
 212   uptr name_len = internal_strlen(name);
 213   InternalMmapVector<char> buffer(kMaxPathLength);
 214   const char *beg = path;
 215   while (true) {
 216     const char *end = internal_strchrnul(beg, kPathSeparator);
 217     uptr prefix_len = end - beg;
 218     if (prefix_len + name_len + 2 <= kMaxPathLength) {
 219       internal_memcpy(buffer.data(), beg, prefix_len);
 220       buffer[prefix_len] = '/';
 221       internal_memcpy(&buffer[prefix_len + 1], name, name_len);
 222       buffer[prefix_len + 1 + name_len] = '\0';
 223       if (FileExists(buffer.data()))
 224         return internal_strdup(buffer.data());
 225     }
 226     if (*end == '\0') break;
 227     beg = end + 1;
 228   }
 229   return nullptr;
 230 }
 231
 232 } // namespace __sanitizer
 233
 234 using namespace __sanitizer;
 235
 236 extern "C" {
 237 void __sanitizer_set_report_path(const char *path) {
 238   report_file.SetReportPath(path);
 239 }
 240
 241 void __sanitizer_set_report_fd(void *fd) {
 242   report_file.fd = (fd_t)reinterpret_cast<uptr>(fd);
 243   report_file.fd_pid = internal_getpid();
 244 }
 245
 246 const char *__sanitizer_get_report_path() {
 247   return report_file.GetReportPath();
 248 }
 249 } // extern "C"
 250
 251 #endif  // !SANITIZER_FUCHSIA