1//===-- sanitizer_wrappers.cc -----------------------------------*- 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// Redirect some functions to sanitizer interceptors.
11//
12//===----------------------------------------------------------------------===//
13
14#include <dlfcn.h>
15#include <errno.h>
16#include <fcntl.h>
17#include <stdarg.h>
18#include <stdio.h>
19#include <unistd.h>
20
21#include <tuple>
22
23// Need to match ../sanitizer_common/sanitizer_internal_defs.h
24#if defined(ARCH_PPC)
25#define OFF_T unsigned long
26#else
27#define OFF_T unsigned long long
28#endif
29
30namespace __sanitizer {
31unsigned long internal_open(const char *filename, int flags);
32unsigned long internal_open(const char *filename, int flags, unsigned mode);
33unsigned long internal_close(int fd);
34unsigned long internal_stat(const char *path, void *buf);
35unsigned long internal_lstat(const char *path, void *buf);
36unsigned long internal_fstat(int fd, void *buf);
37size_t internal_strlen(const char *s);
38unsigned long internal_mmap(void *addr, unsigned long length, int prot,
39                            int flags, int fd, OFF_T offset);
40void *internal_memcpy(void *dest, const void *src, unsigned long n);
41// Used to propagate errno.
42bool internal_iserror(unsigned long retval, int *rverrno = 0);
43}  // namespace __sanitizer
44
45namespace {
46
47template <typename T>
48struct GetTypes;
49
50template <typename R, typename... Args>
51struct GetTypes<R(Args...)> {
52  using Result = R;
53  template <size_t i>
54  struct Arg {
55    using Type = typename std::tuple_element<i, std::tuple<Args...>>::type;
56  };
57};
58
59#define LLVM_SYMBOLIZER_GET_FUNC(Function) \
60  ((__interceptor_##Function)              \
61       ? (__interceptor_##Function)        \
62       : reinterpret_cast<decltype(&Function)>(dlsym(RTLD_NEXT, #Function)))
63
64#define LLVM_SYMBOLIZER_INTERCEPTOR1(Function, ...)               \
65  GetTypes<__VA_ARGS__>::Result __interceptor_##Function(         \
66      GetTypes<__VA_ARGS__>::Arg<0>::Type) __attribute__((weak)); \
67  GetTypes<__VA_ARGS__>::Result Function(                         \
68      GetTypes<__VA_ARGS__>::Arg<0>::Type arg0) {                 \
69    return LLVM_SYMBOLIZER_GET_FUNC(Function)(arg0);              \
70  }
71
72#define LLVM_SYMBOLIZER_INTERCEPTOR2(Function, ...)               \
73  GetTypes<__VA_ARGS__>::Result __interceptor_##Function(         \
74      GetTypes<__VA_ARGS__>::Arg<0>::Type,                        \
75      GetTypes<__VA_ARGS__>::Arg<1>::Type) __attribute__((weak)); \
76  GetTypes<__VA_ARGS__>::Result Function(                         \
77      GetTypes<__VA_ARGS__>::Arg<0>::Type arg0,                   \
78      GetTypes<__VA_ARGS__>::Arg<1>::Type arg1) {                 \
79    return LLVM_SYMBOLIZER_GET_FUNC(Function)(arg0, arg1);        \
80  }
81
82#define LLVM_SYMBOLIZER_INTERCEPTOR3(Function, ...)               \
83  GetTypes<__VA_ARGS__>::Result __interceptor_##Function(         \
84      GetTypes<__VA_ARGS__>::Arg<0>::Type,                        \
85      GetTypes<__VA_ARGS__>::Arg<1>::Type,                        \
86      GetTypes<__VA_ARGS__>::Arg<2>::Type) __attribute__((weak)); \
87  GetTypes<__VA_ARGS__>::Result Function(                         \
88      GetTypes<__VA_ARGS__>::Arg<0>::Type arg0,                   \
89      GetTypes<__VA_ARGS__>::Arg<1>::Type arg1,                   \
90      GetTypes<__VA_ARGS__>::Arg<2>::Type arg2) {                 \
91    return LLVM_SYMBOLIZER_GET_FUNC(Function)(arg0, arg1, arg2);  \
92  }
93
94#define LLVM_SYMBOLIZER_INTERCEPTOR4(Function, ...)                    \
95  GetTypes<__VA_ARGS__>::Result __interceptor_##Function(              \
96      GetTypes<__VA_ARGS__>::Arg<0>::Type,                             \
97      GetTypes<__VA_ARGS__>::Arg<1>::Type,                             \
98      GetTypes<__VA_ARGS__>::Arg<2>::Type,                             \
99      GetTypes<__VA_ARGS__>::Arg<3>::Type) __attribute__((weak));      \
100  GetTypes<__VA_ARGS__>::Result Function(                              \
101      GetTypes<__VA_ARGS__>::Arg<0>::Type arg0,                        \
102      GetTypes<__VA_ARGS__>::Arg<1>::Type arg1,                        \
103      GetTypes<__VA_ARGS__>::Arg<2>::Type arg2,                        \
104      GetTypes<__VA_ARGS__>::Arg<3>::Type arg3) {                      \
105    return LLVM_SYMBOLIZER_GET_FUNC(Function)(arg0, arg1, arg2, arg3); \
106  }
107
108}  // namespace
109
110// C-style interface around internal sanitizer libc functions.
111extern "C" {
112
113#define RETURN_OR_SET_ERRNO(T, res)                   \
114  int rverrno;                                        \
115  if (__sanitizer::internal_iserror(res, &rverrno)) { \
116    errno = rverrno;                                  \
117    return (T)-1;                                     \
118  }                                                   \
119  return (T)res;
120
121int open(const char *filename, int flags, ...) {
122  unsigned long res;
123  if (flags | O_CREAT) {
124    va_list va;
125    va_start(va, flags);
126    unsigned mode = va_arg(va, unsigned);
127    va_end(va);
128    res = __sanitizer::internal_open(filename, flags, mode);
129  } else {
130    res = __sanitizer::internal_open(filename, flags);
131  }
132  RETURN_OR_SET_ERRNO(int, res);
133}
134
135int close(int fd) {
136  unsigned long res = __sanitizer::internal_close(fd);
137  RETURN_OR_SET_ERRNO(int, res);
138}
139
140#define STAT(func, arg, buf)                                  \
141  unsigned long res = __sanitizer::internal_##func(arg, buf); \
142  RETURN_OR_SET_ERRNO(int, res);
143
144int stat(const char *path, struct stat *buf) { STAT(stat, path, buf); }
145
146int lstat(const char *path, struct stat *buf) { STAT(lstat, path, buf); }
147
148int fstat(int fd, struct stat *buf) { STAT(fstat, fd, buf); }
149
150// Redirect versioned stat functions to the __sanitizer::internal() as well.
151int __xstat(int version, const char *path, struct stat *buf) {
152  STAT(stat, path, buf);
153}
154
155int __lxstat(int version, const char *path, struct stat *buf) {
156  STAT(lstat, path, buf);
157}
158
159int __fxstat(int version, int fd, struct stat *buf) { STAT(fstat, fd, buf); }
160
161size_t strlen(const char *s) { return __sanitizer::internal_strlen(s); }
162
163void *mmap(void *addr, size_t length, int prot, int flags, int fd,
164           off_t offset) {
165  unsigned long res = __sanitizer::internal_mmap(
166      addr, (unsigned long)length, prot, flags, fd, (unsigned long long)offset);
167  RETURN_OR_SET_ERRNO(void *, res);
168}
169
170LLVM_SYMBOLIZER_INTERCEPTOR3(read, ssize_t(int, void *, size_t))
171LLVM_SYMBOLIZER_INTERCEPTOR4(pread, ssize_t(int, void *, size_t, off_t))
172LLVM_SYMBOLIZER_INTERCEPTOR4(pread64, ssize_t(int, void *, size_t, off64_t))
173LLVM_SYMBOLIZER_INTERCEPTOR2(realpath, char *(const char *, char *))
174
175LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_cond_broadcast, int(pthread_cond_t *))
176LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_cond_wait,
177                             int(pthread_cond_t *, pthread_mutex_t *))
178LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutex_lock, int(pthread_mutex_t *))
179LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutex_unlock, int(pthread_mutex_t *))
180LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutex_destroy, int(pthread_mutex_t *))
181LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_mutex_init,
182                             int(pthread_mutex_t *,
183                                 const pthread_mutexattr_t *))
184LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutexattr_destroy,
185                             int(pthread_mutexattr_t *))
186LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_mutexattr_init, int(pthread_mutexattr_t *))
187LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_mutexattr_settype,
188                             int(pthread_mutexattr_t *, int))
189LLVM_SYMBOLIZER_INTERCEPTOR1(pthread_getspecific, void *(pthread_key_t))
190LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_key_create,
191                             int(pthread_key_t *, void (*)(void *)))
192LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_once,
193                             int(pthread_once_t *, void (*)(void)))
194LLVM_SYMBOLIZER_INTERCEPTOR2(pthread_setspecific,
195                             int(pthread_key_t, const void *))
196LLVM_SYMBOLIZER_INTERCEPTOR3(pthread_sigmask,
197                             int(int, const sigset_t *, sigset_t *))
198
199}  // extern "C"
200