1 //===-- sanitizer_linux.h ---------------------------------------*- C++ -*-===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // Linux-specific syscall wrappers and classes.
11 //
12 //===----------------------------------------------------------------------===//
13 #ifndef SANITIZER_LINUX_H
14 #define SANITIZER_LINUX_H
15 
16 #include "sanitizer_platform.h"
17 #if SANITIZER_FREEBSD || SANITIZER_LINUX
18 #include "sanitizer_common.h"
19 #include "sanitizer_internal_defs.h"
20 #include "sanitizer_posix.h"
21 #include "sanitizer_platform_limits_posix.h"
22 
23 struct link_map;  // Opaque type returned by dlopen().
24 struct sigaltstack;
25 
26 namespace __sanitizer {
27 // Dirent structure for getdents(). Note that this structure is different from
28 // the one in <dirent.h>, which is used by readdir().
29 struct linux_dirent;
30 
31 // Syscall wrappers.
32 uptr internal_getdents(fd_t fd, struct linux_dirent *dirp, unsigned int count);
33 uptr internal_sigaltstack(const struct sigaltstack* ss,
34                           struct sigaltstack* oss);
35 uptr internal_sigprocmask(int how, __sanitizer_sigset_t *set,
36     __sanitizer_sigset_t *oldset);
37 void internal_sigfillset(__sanitizer_sigset_t *set);
38 
39 // Linux-only syscalls.
40 #if SANITIZER_LINUX
41 uptr internal_prctl(int option, uptr arg2, uptr arg3, uptr arg4, uptr arg5);
42 // Used only by sanitizer_stoptheworld. Signal handlers that are actually used
43 // (like the process-wide error reporting SEGV handler) must use
44 // internal_sigaction instead.
45 int internal_sigaction_norestorer(int signum, const void *act, void *oldact);
46 void internal_sigdelset(__sanitizer_sigset_t *set, int signum);
47 #if defined(__x86_64__) || defined(__mips__)
48 uptr internal_clone(int (*fn)(void *), void *child_stack, int flags, void *arg,
49                     int *parent_tidptr, void *newtls, int *child_tidptr);
50 #endif
51 #endif  // SANITIZER_LINUX
52 
53 // This class reads thread IDs from /proc/<pid>/task using only syscalls.
54 class ThreadLister {
55  public:
56   explicit ThreadLister(int pid);
57   ~ThreadLister();
58   // GetNextTID returns -1 if the list of threads is exhausted, or if there has
59   // been an error.
60   int GetNextTID();
61   void Reset();
62   bool error();
63 
64  private:
65   bool GetDirectoryEntries();
66 
67   int pid_;
68   int descriptor_;
69   InternalScopedBuffer<char> buffer_;
70   bool error_;
71   struct linux_dirent* entry_;
72   int bytes_read_;
73 };
74 
75 // Exposed for testing.
76 uptr ThreadDescriptorSize();
77 uptr ThreadSelf();
78 uptr ThreadSelfOffset();
79 
80 // Matches a library's file name against a base name (stripping path and version
81 // information).
82 bool LibraryNameIs(const char *full_name, const char *base_name);
83 
84 // Cache the value of /proc/self/exe.
85 void CacheBinaryName();
86 
87 // Call cb for each region mapped by map.
88 void ForEachMappedRegion(link_map *map, void (*cb)(const void *, uptr));
89 }  // namespace __sanitizer
90 
91 #endif  // SANITIZER_FREEBSD || SANITIZER_LINUX
92 #endif  // SANITIZER_LINUX_H
93