1 //===-- sanitizer_file.h ---------------------------------------*- C++ -*-===//
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 run-time libraries of sanitizers.
10 // It declares filesystem-related interfaces.  This is separate from
11 // sanitizer_common.h so that it's simpler to disable all the filesystem
12 // support code for a port that doesn't use it.
13 //
14 //===---------------------------------------------------------------------===//
15 #ifndef SANITIZER_FILE_H
16 #define SANITIZER_FILE_H
17 
18 #include "sanitizer_interface_internal.h"
19 #include "sanitizer_internal_defs.h"
20 #include "sanitizer_libc.h"
21 #include "sanitizer_mutex.h"
22 
23 namespace __sanitizer {
24 
25 struct ReportFile {
26   void Write(const char *buffer, uptr length);
27   bool SupportsColors();
28   void SetReportPath(const char *path);
29 
30   // Don't use fields directly. They are only declared public to allow
31   // aggregate initialization.
32 
33   // Protects fields below.
34   StaticSpinMutex *mu;
35   // Opened file descriptor. Defaults to stderr. It may be equal to
36   // kInvalidFd, in which case new file will be opened when necessary.
37   fd_t fd;
38   // Path prefix of report file, set via __sanitizer_set_report_path.
39   char path_prefix[kMaxPathLength];
40   // Full path to report, obtained as <path_prefix>.PID
41   char full_path[kMaxPathLength];
42   // PID of the process that opened fd. If a fork() occurs,
43   // the PID of child will be different from fd_pid.
44   uptr fd_pid;
45 
46  private:
47   void ReopenIfNecessary();
48 };
49 extern ReportFile report_file;
50 
51 enum FileAccessMode {
52   RdOnly,
53   WrOnly,
54   RdWr
55 };
56 
57 // Returns kInvalidFd on error.
58 fd_t OpenFile(const char *filename, FileAccessMode mode,
59               error_t *errno_p = nullptr);
60 void CloseFile(fd_t);
61 
62 // Return true on success, false on error.
63 bool ReadFromFile(fd_t fd, void *buff, uptr buff_size,
64                   uptr *bytes_read = nullptr, error_t *error_p = nullptr);
65 bool WriteToFile(fd_t fd, const void *buff, uptr buff_size,
66                  uptr *bytes_written = nullptr, error_t *error_p = nullptr);
67 
68 // Scoped file handle closer.
69 struct FileCloser {
70   explicit FileCloser(fd_t fd) : fd(fd) {}
71   ~FileCloser() { CloseFile(fd); }
72   fd_t fd;
73 };
74 
75 bool SupportsColoredOutput(fd_t fd);
76 
77 // OS
78 const char *GetPwd();
79 bool FileExists(const char *filename);
80 char *FindPathToBinary(const char *name);
81 bool IsPathSeparator(const char c);
82 bool IsAbsolutePath(const char *path);
83 // Starts a subprocess and returs its pid.
84 // If *_fd parameters are not kInvalidFd their corresponding input/output
85 // streams will be redirect to the file. The files will always be closed
86 // in parent process even in case of an error.
87 // The child process will close all fds after STDERR_FILENO
88 // before passing control to a program.
89 pid_t StartSubprocess(const char *filename, const char *const argv[],
90                       const char *const envp[], fd_t stdin_fd = kInvalidFd,
91                       fd_t stdout_fd = kInvalidFd, fd_t stderr_fd = kInvalidFd);
92 // Checks if specified process is still running
93 bool IsProcessRunning(pid_t pid);
94 // Waits for the process to finish and returns its exit code.
95 // Returns -1 in case of an error.
96 int WaitForProcess(pid_t pid);
97 
98 // Maps given file to virtual memory, and returns pointer to it
99 // (or NULL if mapping fails). Stores the size of mmaped region
100 // in '*buff_size'.
101 void *MapFileToMemory(const char *file_name, uptr *buff_size);
102 void *MapWritableFileToMemory(void *addr, uptr size, fd_t fd, OFF_T offset);
103 
104 }  // namespace __sanitizer
105 
106 #endif  // SANITIZER_FILE_H
107