1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include <sys/types.h>  // Include something that will define __GLIBC__.
6
7// The entire file is wrapped in this #if. We do this so this .cc file can be
8// compiled, even on a non-newlib build.
9#if defined(__native_client__) && !defined(__GLIBC__) && !defined(__BIONIC__)
10
11#include "nacl_io/kernel_wrap.h"
12
13#include <dirent.h>
14#include <errno.h>
15#include <irt.h>
16#include <irt_dev.h>
17#include <sys/mman.h>
18#include <sys/stat.h>
19#include <sys/time.h>
20
21#include "nacl_io/kernel_intercept.h"
22#include "nacl_io/kernel_wrap_real.h"
23#include "nacl_io/log.h"
24
25EXTERN_C_BEGIN
26
27// Macro to get the REAL function pointer
28#define REAL(name) __nacl_irt_##name##_real
29
30// Macro to get the WRAP function
31#define WRAP(name) __nacl_irt_##name##_wrap
32
33// Declare REAL function pointer.
34#define DECLARE_REAL_PTR(group, name) \
35  typeof(__libnacl_irt_##group.name) REAL(name);
36
37// Assign the REAL function pointer.
38#define ASSIGN_REAL_PTR(group, name) REAL(name) = __libnacl_irt_##group.name;
39
40// Switch IRT's pointer to the REAL pointer
41#define USE_REAL(group, name) \
42  __libnacl_irt_##group.name = (typeof(REAL(name)))REAL(name);
43
44// Switch the IRT's pointer to the WRAP function
45#define USE_WRAP(group, name) \
46  __libnacl_irt_##group.name = (typeof(REAL(name)))WRAP(name);
47
48extern void __libnacl_irt_dev_filename_init(void);
49
50extern struct nacl_irt_basic __libnacl_irt_basic;
51extern struct nacl_irt_fdio __libnacl_irt_fdio;
52extern struct nacl_irt_dev_fdio __libnacl_irt_dev_fdio;
53extern struct nacl_irt_dev_filename __libnacl_irt_dev_filename;
54extern struct nacl_irt_memory __libnacl_irt_memory;
55
56// Create function pointers to the REAL implementation
57#define EXPAND_SYMBOL_LIST_OPERATION(OP) \
58  OP(basic, exit);                       \
59  OP(fdio, close);                       \
60  OP(fdio, dup);                         \
61  OP(fdio, dup2);                        \
62  OP(fdio, read);                        \
63  OP(fdio, write);                       \
64  OP(fdio, seek);                        \
65  OP(fdio, fstat);                       \
66  OP(fdio, getdents);                    \
67  OP(dev_fdio, fchdir);                  \
68  OP(dev_fdio, fchmod);                  \
69  OP(dev_fdio, fsync);                   \
70  OP(dev_fdio, fdatasync);               \
71  OP(dev_fdio, ftruncate);               \
72  OP(dev_fdio, isatty);                  \
73  OP(dev_filename, open);                \
74  OP(dev_filename, stat);                \
75  OP(dev_filename, mkdir);               \
76  OP(dev_filename, rmdir);               \
77  OP(dev_filename, chdir);               \
78  OP(dev_filename, getcwd);              \
79  OP(dev_filename, unlink);              \
80  OP(dev_filename, truncate);            \
81  OP(dev_filename, lstat);               \
82  OP(dev_filename, link);                \
83  OP(dev_filename, rename);              \
84  OP(dev_filename, symlink);             \
85  OP(dev_filename, chmod);               \
86  OP(dev_filename, access);              \
87  OP(dev_filename, readlink);            \
88  OP(dev_filename, utimes);              \
89  OP(memory, mmap);                      \
90  OP(memory, munmap);
91
92EXPAND_SYMBOL_LIST_OPERATION(DECLARE_REAL_PTR);
93
94int WRAP(close)(int fd) {
95  ERRNO_RTN(ki_close(fd));
96}
97
98int WRAP(dup)(int fd, int* newfd) {
99  *newfd = ki_dup(fd);
100  ERRNO_RTN(*newfd);
101}
102
103int WRAP(dup2)(int fd, int newfd) {
104  newfd = ki_dup2(fd, newfd);
105  ERRNO_RTN(newfd);
106}
107
108void WRAP(exit)(int status) {
109  ki_exit(status);
110}
111
112int WRAP(read)(int fd, void* buf, size_t count, size_t* nread) {
113  ssize_t signed_nread = ki_read(fd, buf, count);
114  *nread = static_cast<size_t>(signed_nread);
115  ERRNO_RTN(signed_nread);
116}
117
118int WRAP(write)(int fd, const void* buf, size_t count, size_t* nwrote) {
119  ssize_t signed_nwrote = ki_write(fd, buf, count);
120  *nwrote = static_cast<size_t>(signed_nwrote);
121  ERRNO_RTN(signed_nwrote);
122}
123
124int WRAP(seek)(int fd, off_t offset, int whence, off_t* new_offset) {
125  *new_offset = ki_lseek(fd, offset, whence);
126  ERRNO_RTN(*new_offset);
127}
128
129int WRAP(fstat)(int fd, struct stat* buf) {
130  ERRNO_RTN(ki_fstat(fd, buf));
131}
132
133int WRAP(getdents)(int fd, dirent* buf, size_t count, size_t* nread) {
134  int rtn = ki_getdents(fd, buf, count);
135  RTN_ERRNO_IF(rtn < 0);
136  *nread = rtn;
137  return 0;
138}
139
140int WRAP(fchdir)(int fd) {
141  ERRNO_RTN(ki_fchdir(fd));
142}
143
144int WRAP(fchmod)(int fd, mode_t mode) {
145  ERRNO_RTN(ki_fchmod(fd, mode));
146}
147
148int WRAP(fsync)(int fd) {
149  ERRNO_RTN(ki_fsync(fd));
150}
151
152int WRAP(fdatasync)(int fd) {
153  ERRNO_RTN(ki_fdatasync(fd));
154}
155
156int WRAP(ftruncate)(int fd, off_t length) {
157  ERRNO_RTN(ki_ftruncate(fd, length));
158}
159
160int WRAP(isatty)(int fd, int* result) {
161  *result = ki_isatty(fd);
162  RTN_ERRNO_IF(*result == 0);
163  return 0;
164}
165
166int WRAP(mmap)(void** addr,
167               size_t length,
168               int prot,
169               int flags,
170               int fd,
171               off_t offset) {
172  if (flags & MAP_ANONYMOUS)
173    return REAL(mmap)(addr, length, prot, flags, fd, offset);
174
175  *addr = ki_mmap(*addr, length, prot, flags, fd, offset);
176  RTN_ERRNO_IF(*addr == (void*)-1);
177  return 0;
178}
179
180int WRAP(munmap)(void* addr, size_t length) {
181  // Always let the real munmap run on the address range. It is not an error if
182  // there are no mapped pages in that range.
183  ki_munmap(addr, length);
184  return REAL(munmap)(addr, length);
185}
186
187int WRAP(open)(const char* pathname, int oflag, mode_t cmode, int* newfd) {
188  *newfd = ki_open(pathname, oflag);
189  ERRNO_RTN(*newfd);
190}
191
192int WRAP(stat)(const char* pathname, struct stat* buf) {
193  ERRNO_RTN(ki_stat(pathname, buf));
194}
195
196int WRAP(mkdir)(const char* pathname, mode_t mode) {
197  ERRNO_RTN(ki_mkdir(pathname, mode));
198}
199
200int WRAP(rmdir)(const char* pathname) {
201  ERRNO_RTN(ki_rmdir(pathname));
202}
203
204int WRAP(chdir)(const char* pathname) {
205  ERRNO_RTN(ki_chdir(pathname));
206}
207
208int WRAP(getcwd)(char* pathname, size_t len) {
209  char* rtn = ki_getcwd(pathname, len);
210  RTN_ERRNO_IF(NULL == rtn);
211  return 0;
212}
213
214int WRAP(unlink)(const char* pathname) {
215  ERRNO_RTN(ki_unlink(pathname));
216}
217
218int WRAP(truncate)(const char* pathname, off_t length) {
219  ERRNO_RTN(ki_truncate(pathname, length));
220}
221
222int WRAP(lstat)(const char* pathname, struct stat* buf) {
223  ERRNO_RTN(ki_lstat(pathname, buf));
224}
225
226int WRAP(link)(const char* pathname, const char* newpath) {
227  ERRNO_RTN(ki_link(pathname, newpath));
228}
229
230int WRAP(rename)(const char* pathname, const char* newpath) {
231  ERRNO_RTN(ki_rename(pathname, newpath));
232}
233
234int WRAP(symlink)(const char* pathname, const char* newpath) {
235  ERRNO_RTN(ki_symlink(pathname, newpath));
236}
237
238int WRAP(chmod)(const char* pathname, mode_t mode) {
239  ERRNO_RTN(ki_chmod(pathname, mode));
240}
241
242int WRAP(access)(const char* pathname, int amode) {
243  ERRNO_RTN(ki_access(pathname, amode));
244}
245
246int WRAP(readlink)(const char* pathname,
247                   char* buf,
248                   size_t count,
249                   size_t* nread) {
250  int rtn = ki_readlink(pathname, buf, count);
251  RTN_ERRNO_IF(rtn < 0);
252  *nread = rtn;
253  return 0;
254}
255
256int WRAP(utimes)(const char* pathname, const struct timeval times[2]) {
257  ERRNO_RTN(ki_utimes(pathname, times));
258}
259
260static void assign_real_pointers() {
261  static bool assigned = false;
262  if (!assigned) {
263    __libnacl_irt_dev_filename_init();
264    EXPAND_SYMBOL_LIST_OPERATION(ASSIGN_REAL_PTR)
265    assigned = true;
266  }
267}
268
269#define CHECK_REAL(func) \
270  if (!REAL(func))       \
271    assign_real_pointers();
272
273// "real" functions, i.e. the unwrapped original functions.
274
275int _real_close(int fd) {
276  CHECK_REAL(close);
277  return REAL(close)(fd);
278}
279
280void _real_exit(int status) {
281  CHECK_REAL(exit);
282  REAL(exit)(status);
283}
284
285int _real_fstat(int fd, struct stat* buf) {
286  CHECK_REAL(fstat);
287  return REAL(fstat)(fd, buf);
288}
289
290int _real_isatty(int fd, int* result) {
291  CHECK_REAL(isatty);
292  return REAL(isatty)(fd, result);
293}
294
295int _real_getdents(int fd, void* nacl_buf, size_t nacl_count, size_t* nread) {
296  CHECK_REAL(getdents);
297  return REAL(getdents)(fd, static_cast<dirent*>(nacl_buf), nacl_count, nread);
298}
299
300int _real_lseek(int fd, off_t offset, int whence, off_t* new_offset) {
301  CHECK_REAL(seek);
302  return REAL(seek)(fd, offset, whence, new_offset);
303}
304
305int _real_mkdir(const char* pathname, mode_t mode) {
306  return ENOSYS;
307}
308
309int _real_mmap(void** addr,
310               size_t length,
311               int prot,
312               int flags,
313               int fd,
314               off_t offset) {
315  CHECK_REAL(mmap);
316  return REAL(mmap)(addr, length, prot, flags, fd, offset);
317}
318
319int _real_munmap(void* addr, size_t length) {
320  CHECK_REAL(munmap);
321  return REAL(munmap)(addr, length);
322}
323
324int _real_open(const char* pathname, int oflag, mode_t cmode, int* newfd) {
325  CHECK_REAL(open);
326  return REAL(open)(pathname, oflag, cmode, newfd);
327}
328
329int _real_open_resource(const char* file, int* fd) {
330  return ENOSYS;
331}
332
333int _real_read(int fd, void* buf, size_t count, size_t* nread) {
334  CHECK_REAL(read);
335  return REAL(read)(fd, buf, count, nread);
336}
337
338int _real_rmdir(const char* pathname) {
339  return ENOSYS;
340}
341
342int _real_write(int fd, const void* buf, size_t count, size_t* nwrote) {
343  CHECK_REAL(write);
344  return REAL(write)(fd, buf, count, nwrote);
345}
346
347static bool s_wrapped = false;
348
349void kernel_wrap_init() {
350  if (!s_wrapped) {
351    LOG_TRACE("kernel_wrap_init");
352    assign_real_pointers();
353    EXPAND_SYMBOL_LIST_OPERATION(USE_WRAP)
354    s_wrapped = true;
355  }
356}
357
358void kernel_wrap_uninit() {
359  if (s_wrapped) {
360    LOG_TRACE("kernel_wrap_uninit");
361    EXPAND_SYMBOL_LIST_OPERATION(USE_REAL)
362    s_wrapped = false;
363  }
364}
365
366EXTERN_C_END
367
368#endif  // defined(__native_client__) && !defined(__GLIBC__) ...
369