1 /*
2  * Copyright (C) 2013 The Android Open Source Project
3  * All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  *  * Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  *  * Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
16  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
17  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
18  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
19  * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
21  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
22  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
23  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
24  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
25  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 // This file perpetuates the mistakes of the past, but only for 32-bit targets.
30 #if !defined(__LP64__)
31 
32 #include <ctype.h>
33 #include <dirent.h>
34 #include <inttypes.h>
35 #include <pthread.h>
36 #include <signal.h>
37 #include <stdio.h>
38 #include <stdlib.h>
39 #include <string.h>
40 #include <sys/resource.h>
41 #include <sys/syscall.h>
42 #include <sys/time.h>
43 #include <sys/types.h>
44 #include <sys/wait.h>
45 #include <unistd.h>
46 #include <wchar.h>
47 
48 // These were accidentally declared in <unistd.h> because we stupidly used to inline
49 // getpagesize() and __getpageshift(). Needed for backwards compatibility with old NDK apps.
50 extern "C" {
51   unsigned int __page_size = PAGE_SIZE;
52   unsigned int __page_shift = 12;
53 }
54 
55 // TODO: remove this backward compatibility hack (for jb-mr1 strace binaries).
__wait4(pid_t pid,int * status,int options,struct rusage * rusage)56 extern "C" pid_t __wait4(pid_t pid, int* status, int options, struct rusage* rusage) {
57   return wait4(pid, status, options, rusage);
58 }
59 
60 // TODO: does anything still need this?
__open()61 extern "C" int __open() {
62   abort();
63 }
64 
65 // TODO: does anything still need this?
__get_tls()66 extern "C" void** __get_tls() {
67 #include "private/__get_tls.h"
68   return __get_tls();
69 }
70 
71 // This non-standard function was in our <string.h> for some reason.
memswap(void * m1,void * m2,size_t n)72 extern "C" void memswap(void* m1, void* m2, size_t n) {
73   char* p = reinterpret_cast<char*>(m1);
74   char* p_end = p + n;
75   char* q = reinterpret_cast<char*>(m2);
76   while (p < p_end) {
77     char tmp = *p;
78     *p = *q;
79     *q = tmp;
80     p++;
81     q++;
82   }
83 }
84 
pthread_attr_setstackaddr(pthread_attr_t *,void *)85 extern "C" int pthread_attr_setstackaddr(pthread_attr_t*, void*) {
86   // This was removed from POSIX.1-2008, and is not implemented on bionic.
87   // Needed for ABI compatibility with the NDK.
88   return ENOSYS;
89 }
90 
pthread_attr_getstackaddr(const pthread_attr_t * attr,void ** stack_addr)91 extern "C" int pthread_attr_getstackaddr(const pthread_attr_t* attr, void** stack_addr) {
92   // This was removed from POSIX.1-2008.
93   // Needed for ABI compatibility with the NDK.
94   *stack_addr = (char*)attr->stack_base + attr->stack_size;
95   return 0;
96 }
97 
98 // Non-standard cruft that should only ever have been in system/core/toolbox.
strtotimeval(const char * str,struct timeval * ts)99 extern "C" char* strtotimeval(const char* str, struct timeval* ts) {
100   char* s;
101   ts->tv_sec = strtoumax(str, &s, 10);
102 
103   long fractional_seconds = 0;
104   if (*s == '.') {
105     s++;
106     int count = 0;
107 
108     // Read up to 6 digits (microseconds).
109     while (*s && isdigit(*s)) {
110       if (++count < 7) {
111         fractional_seconds = fractional_seconds*10 + (*s - '0');
112       }
113       s++;
114     }
115 
116     for (; count < 6; count++) {
117       fractional_seconds *= 10;
118     }
119   }
120 
121   ts->tv_usec = fractional_seconds;
122   return s;
123 }
124 
digitval(int ch)125 static inline int digitval(int ch) {
126   unsigned d;
127 
128   d = (unsigned)(ch - '0');
129   if (d < 10) return (int)d;
130 
131   d = (unsigned)(ch - 'a');
132   if (d < 6) return (int)(d+10);
133 
134   d = (unsigned)(ch - 'A');
135   if (d < 6) return (int)(d+10);
136 
137   return -1;
138 }
139 
140 // This non-standard function was in our <inttypes.h> for some reason.
strntoumax(const char * nptr,char ** endptr,int base,size_t n)141 extern "C" uintmax_t strntoumax(const char *nptr, char **endptr, int base, size_t n) {
142   const unsigned char*  p   = (const unsigned char *)nptr;
143   const unsigned char*  end = p + n;
144   int                   minus = 0;
145   uintmax_t             v = 0;
146   int                   d;
147 
148   while (p < end && isspace(*p)) {
149     p++;
150   }
151 
152   if (p < end) {
153     char c = p[0];
154     if (c == '-' || c == '+') {
155       minus = (c == '-');
156       p++;
157     }
158   }
159 
160   if (base == 0) {
161     if (p+2 < end && p[0] == '0' && (p[1] == 'x' || p[1] == 'X')) {
162       p += 2;
163       base = 16;
164     } else if (p+1 < end && p[0] == '0') {
165       p   += 1;
166       base = 8;
167     } else {
168       base = 10;
169     }
170   } else if (base == 16) {
171     if (p+2 < end && p[0] == '0' && (p[1] == 'x' || p[1] == 'X')) {
172       p += 2;
173     }
174   }
175 
176   while (p < end && (d = digitval(*p)) >= 0 && d < base) {
177     v = v*base + d;
178     p += 1;
179   }
180 
181   if (endptr) {
182     *endptr = (char*) p;
183   }
184 
185   return minus ? -v : v;
186 }
187 
188 // This non-standard function was in our <inttypes.h> for some reason.
strntoimax(const char * nptr,char ** endptr,int base,size_t n)189 extern "C" intmax_t strntoimax(const char* nptr, char** endptr, int base, size_t n) {
190   return (intmax_t) strntoumax(nptr, endptr, base, n);
191 }
192 
193 // POSIX calls this dprintf, but LP32 Android had fdprintf instead.
fdprintf(int fd,const char * fmt,...)194 extern "C" int fdprintf(int fd, const char* fmt, ...) {
195   va_list ap;
196   va_start(ap, fmt);
197   int rc = vdprintf(fd, fmt, ap);
198   va_end(ap);
199   return rc;
200 }
201 
202 // POSIX calls this vdprintf, but LP32 Android had fdprintf instead.
vfdprintf(int fd,const char * fmt,va_list ap)203 extern "C" int vfdprintf(int fd, const char* fmt, va_list ap) {
204   return vdprintf(fd, fmt, ap);
205 }
206 
207 #define __futex_wake __real_futex_wake
208 #define __futex_wait __real_futex_wait
209 #include "private/bionic_futex.h"
210 #undef __futex_wake
211 #undef __futex_wait
212 
213 // This used to be in <sys/atomics.h>.
__futex_wake(volatile void * ftx,int count)214 extern "C" int __futex_wake(volatile void* ftx, int count) {
215   return __real_futex_wake(ftx, count);
216 }
217 
218 // This used to be in <sys/atomics.h>.
__futex_wait(volatile void * ftx,int value,const struct timespec * timeout)219 extern "C" int __futex_wait(volatile void* ftx, int value, const struct timespec* timeout) {
220   return __real_futex_wait(ftx, value, timeout);
221 }
222 
223 // Unity's libmono uses this.
tkill(pid_t tid,int sig)224 extern "C" int tkill(pid_t tid, int sig) {
225   return syscall(__NR_tkill, tid, sig);
226 }
227 
228 // This was removed from POSIX 2008.
wcswcs(wchar_t * haystack,wchar_t * needle)229 extern "C" wchar_t* wcswcs(wchar_t* haystack, wchar_t* needle) {
230   return wcsstr(haystack, needle);
231 }
232 
233 // This was removed from POSIX 2008.
bsd_signal(int signum,sighandler_t handler)234 extern "C" sighandler_t bsd_signal(int signum, sighandler_t handler) {
235   return signal(signum, handler);
236 }
237 
238 // sysv_signal() was never in POSIX.
239 extern sighandler_t _signal(int signum, sighandler_t handler, int flags);
sysv_signal(int signum,sighandler_t handler)240 extern "C" sighandler_t sysv_signal(int signum, sighandler_t handler) {
241   return _signal(signum, handler, SA_RESETHAND);
242 }
243 
244 // This is a system call that was never in POSIX. Use readdir(3) instead.
245 extern "C" int __getdents64(unsigned int, dirent*, unsigned int);
getdents(unsigned int fd,dirent * dirp,unsigned int count)246 extern "C" int getdents(unsigned int fd, dirent* dirp, unsigned int count) {
247   return __getdents64(fd, dirp, count);
248 }
249 
250 // This is a BSDism that we never implemented correctly. Used by Firefox.
issetugid()251 extern "C" int issetugid() {
252   return 0;
253 }
254 
255 // This was removed from POSIX 2004.
wait3(int * status,int options,struct rusage * rusage)256 extern "C" pid_t wait3(int* status, int options, struct rusage* rusage) {
257   return wait4(-1, status, options, rusage);
258 }
259 
260 // This was removed from POSIX 2004.
getdtablesize()261 extern "C" int getdtablesize() {
262   struct rlimit r;
263 
264   if (getrlimit(RLIMIT_NOFILE, &r) < 0) {
265     return sysconf(_SC_OPEN_MAX);
266   }
267 
268   return r.rlim_cur;
269 }
270 
271 // Only used by ftime, which was removed from POSIX 2008.
272 struct timeb {
273   time_t          time;
274   unsigned short  millitm;
275   short           timezone;
276   short           dstflag;
277 };
278 
279 // This was removed from POSIX 2008.
ftime(struct timeb * tb)280 extern "C" int ftime(struct timeb* tb) {
281   struct timeval  tv;
282   struct timezone tz;
283 
284   if (gettimeofday(&tv, &tz) < 0)
285     return -1;
286 
287   tb->time    = tv.tv_sec;
288   tb->millitm = (tv.tv_usec + 500) / 1000;
289 
290   if (tb->millitm == 1000) {
291     ++tb->time;
292     tb->millitm = 0;
293   }
294 
295   tb->timezone = tz.tz_minuteswest;
296   tb->dstflag  = tz.tz_dsttime;
297 
298   return 0;
299 }
300 
301 // This was removed from POSIX 2008.
index(const char * str,int ch)302 extern "C" char* index(const char* str, int ch) {
303   return strchr(str, ch);
304 }
305 
306 // This was removed from BSD.
arc4random_stir(void)307 extern "C" void arc4random_stir(void) {
308   // The current implementation stirs itself as needed.
309 }
310 
311 // This was removed from BSD.
arc4random_addrandom(unsigned char *,int)312 extern "C" void arc4random_addrandom(unsigned char*, int) {
313   // The current implementation adds randomness as needed.
314 }
315 
316 // Old versions of the NDK did not export malloc_usable_size, but did
317 // export dlmalloc_usable_size. We are moving away from dlmalloc in L
318 // so make this call malloc_usable_size.
dlmalloc_usable_size(void * ptr)319 extern "C" size_t dlmalloc_usable_size(void* ptr) {
320   return malloc_usable_size(ptr);
321 }
322 
323 // Older versions of appportable used dlmalloc directly instead of malloc,
324 // so export this compatibility shim that simply calls malloc.
dlmalloc(size_t size)325 extern "C" void* dlmalloc(size_t size) {
326   return malloc(size);
327 }
328 
329 #endif
330