No more patching libc.a on 64bit platforms

native/src/Application.mk

@@ -4,7 +4,7 @@ APP_CFLAGS       := -Wall -Oz -fomit-frame-pointer -flto
 APP_LDFLAGS      := -flto
 APP_CPPFLAGS     := -std=c++20
 APP_STL          := none
-APP_PLATFORM     := android-21
+APP_PLATFORM     := android-23
 APP_THIN_ARCHIVE := true
 APP_STRIP_MODE   := --strip-all
 

native/src/base/compat/compat.cpp

@@ -10,11 +10,13 @@
 #include <sys/syscall.h>
 #include <sys/stat.h>
 
+#if !defined(__LP64__)
 extern "C" {
 
 // Original source: https://github.com/freebsd/freebsd/blob/master/contrib/file/src/getline.c
 // License: BSD, full copyright notice please check original source
 
+[[gnu::weak]]
 ssize_t getdelim(char **buf, size_t *bufsiz, int delimiter, FILE *fp) {
     char *ptr, *eptr;
 
@@ -51,14 +53,17 @@ ssize_t getdelim(char **buf, size_t *bufsiz, int delimiter, FILE *fp) {
     }
 }
 
+[[gnu::weak]]
 ssize_t getline(char **buf, size_t *bufsiz, FILE *fp) {
     return getdelim(buf, bufsiz, '\n', fp);
 }
 
+[[gnu::weak]]
 FILE *setmntent(const char *path, const char *mode) {
     return fopen(path, mode);
 }
 
+[[gnu::weak]]
 int endmntent(FILE *fp) {
     if (fp != nullptr) {
         fclose(fp);
@@ -68,43 +73,53 @@ int endmntent(FILE *fp) {
 
 // Missing system call wrappers
 
+[[gnu::weak]]
 int setns(int fd, int nstype) {
     return syscall(__NR_setns, fd, nstype);
 }
 
+[[gnu::weak]]
 int unshare(int flags) {
     return syscall(__NR_unshare, flags);
 }
 
+[[gnu::weak]]
 int accept4(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags) {
     return syscall(__NR_accept4, sockfd, addr, addrlen, flags);
 }
 
+[[gnu::weak]]
 int dup3(int oldfd, int newfd, int flags) {
     return syscall(__NR_dup3, oldfd, newfd, flags);
 }
 
+[[gnu::weak]]
 ssize_t readlinkat(int dirfd, const char *pathname, char *buf, size_t bufsiz) {
     return syscall(__NR_readlinkat, dirfd, pathname, buf, bufsiz);
 }
 
+[[gnu::weak]]
 int symlinkat(const char *target, int newdirfd, const char *linkpath) {
     return syscall(__NR_symlinkat, target, newdirfd, linkpath);
 }
 
+[[gnu::weak]]
 int linkat(int olddirfd, const char *oldpath,
            int newdirfd, const char *newpath, int flags) {
     return syscall(__NR_linkat, olddirfd, oldpath, newdirfd, newpath, flags);
 }
 
+[[gnu::weak]]
 int inotify_init1(int flags) {
     return syscall(__NR_inotify_init1, flags);
 }
 
+[[gnu::weak]]
 int faccessat(int dirfd, const char *pathname, int mode, int flags) {
     return syscall(__NR_faccessat, dirfd, pathname, mode, flags);
 }
 
+[[gnu::weak]]
 int mkfifo(const char *path, mode_t mode) {
     return mknod(path, (mode & ~S_IFMT) | S_IFIFO, 0);
 }
@@ -113,19 +128,22 @@ int mkfifo(const char *path, mode_t mode) {
 
 #if defined(__arm__)
 // Why the additional 0 is required: https://man7.org/linux/man-pages/man2/syscall.2.html
+[[gnu::weak]]
 int ftruncate64(int fd, off64_t length) {
     return syscall(__NR_ftruncate64, fd, 0, SPLIT_64(length));
 }
 #elif defined(__i386__)
+[[gnu::weak]]
 int ftruncate64(int fd, off64_t length) {
     return syscall(__NR_ftruncate64, fd, SPLIT_64(length));
 }
 #endif
 
-#if !defined(__LP64__)
+[[gnu::weak]]
 void android_set_abort_message(const char *) {}
 
 // Original source: <android/legacy_signal_inlines.h>
+[[gnu::weak]]
 int sigaddset(sigset_t *set, int signum) {
     /* Signal numbers start at 1, but bit positions start at 0. */
     int bit = signum - 1;
@@ -137,6 +155,8 @@ int sigaddset(sigset_t *set, int signum) {
     local_set[bit / LONG_BIT] |= 1UL << (bit % LONG_BIT);
     return 0;
 }
+
+[[gnu::weak]]
 int sigemptyset(sigset_t *set) {
     if (set == nullptr) {
         errno = EINVAL;
@@ -150,6 +170,11 @@ int sigemptyset(sigset_t *set) {
 #undef snprintf
 #include "fortify.hpp"
 
-#endif
+extern FILE __sF[];
+
+[[gnu::weak]] FILE* stdin = &__sF[0];
+[[gnu::weak]] FILE* stdout = &__sF[1];
+[[gnu::weak]] FILE* stderr = &__sF[2];
 
 } // extern "C"
+#endif

native/src/base/compat/fortify.hpp

@@ -26,22 +26,30 @@ static inline void __check_buffer_access(const char* fn, const char* action,
         __fortify_fatal("%s: prevented %zu-byte %s %zu-byte buffer", fn, claim, action, actual);
     }
 }
+
+[[gnu::weak]]
 void* __memcpy_chk(void* dst, const void* src, size_t count, size_t dst_len) {
     __check_count("memcpy", "count", count);
     __check_buffer_access("memcpy", "write into", count, dst_len);
     return __call_bypassing_fortify(memcpy)(dst, src, count);
 }
+
+[[gnu::weak]]
 char* __strcpy_chk(char* dst, const char* src, size_t dst_len) {
     // TODO: optimize so we don't scan src twice.
     size_t src_len = __builtin_strlen(src) + 1;
     __check_buffer_access("strcpy", "write into", src_len, dst_len);
     return __builtin_strcpy(dst, src);
 }
+
+[[gnu::weak]]
 size_t __strlcpy_chk(char* dst, const char* src,
                      size_t supplied_size, size_t dst_len_from_compiler) {
     __check_buffer_access("strlcpy", "write into", supplied_size, dst_len_from_compiler);
     return __call_bypassing_fortify(strlcpy)(dst, src, supplied_size);
 }
+
+[[gnu::weak]]
 char* __strchr_chk(const char* p, int ch, size_t s_len) {
     for (;; ++p, s_len--) {
         if (__predict_false(s_len == 0)) {
@@ -55,6 +63,8 @@ char* __strchr_chk(const char* p, int ch, size_t s_len) {
         }
     }
 }
+
+[[gnu::weak]]
 char* __strcat_chk(char* dst, const char* src, size_t dst_buf_size) {
     char* save = dst;
     size_t dst_len = __strlen_chk(dst, dst_buf_size);
@@ -68,6 +78,8 @@ char* __strcat_chk(char* dst, const char* src, size_t dst_buf_size) {
     }
     return save;
 }
+
+[[gnu::weak]]
 size_t __strlen_chk(const char* s, size_t s_len) {
     // TODO: "prevented" here would be a lie because this strlen can run off the end.
     // strlen is too important to be expensive, so we wanted to be able to call the optimized
@@ -78,6 +90,8 @@ size_t __strlen_chk(const char* s, size_t s_len) {
     }
     return ret;
 }
+
+[[gnu::weak]]
 int __vsprintf_chk(char* dst, int /*flags*/,
                    size_t dst_len_from_compiler, const char* format, va_list va) {
     // The compiler uses SIZE_MAX to mean "no idea", but our vsnprintf rejects sizes that large.
@@ -88,12 +102,16 @@ int __vsprintf_chk(char* dst, int /*flags*/,
     __check_buffer_access("vsprintf", "write into", result + 1, dst_len_from_compiler);
     return result;
 }
+
+[[gnu::weak]]
 mode_t __umask_chk(mode_t mode) {
     if (__predict_false((mode & 0777) != mode)) {
         __fortify_fatal("umask: called with invalid mask %o", mode);
     }
     return __umask_real(mode);
 }
+
+[[gnu::weak]]
 ssize_t __read_chk(int fd, void* buf, size_t count, size_t buf_size) {
     __check_count("read", "count", count);
     __check_buffer_access("read", "write into", count, buf_size);
@@ -105,11 +123,22 @@ static inline bool needs_mode(int flags) {
 static inline int force_O_LARGEFILE(int flags) {
     return flags | O_LARGEFILE;
 }
+
+[[gnu::weak]]
 int __open_2(const char* pathname, int flags) {
     if (needs_mode(flags)) __fortify_fatal("open: called with O_CREAT/O_TMPFILE but no mode");
     return __openat_real(AT_FDCWD, pathname, force_O_LARGEFILE(flags), 0);
 }
+
+[[gnu::weak]]
 int __openat_2(int fd, const char* pathname, int flags) {
     if (needs_mode(flags)) __fortify_fatal("open: called with O_CREAT/O_TMPFILE but no mode");
     return __openat_real(fd, pathname, force_O_LARGEFILE(flags), 0);
 }
+
+[[gnu::weak]]
+int __vsnprintf_chk(char* dst, size_t supplied_size, int /*flags*/,
+                               size_t dst_len_from_compiler, const char* format, va_list va) {
+    __check_buffer_access("vsnprintf", "write into", supplied_size, dst_len_from_compiler);
+    return vsnprintf(dst, supplied_size, format, va);
+}

native/src/base/missing.hpp

@@ -6,15 +6,6 @@
 #include <cerrno>
 #include <cstdio>
 
-static inline int sigtimedwait(const sigset_t* set, siginfo_t* info, const timespec* timeout) {
-    union {
-        sigset_t set;
-        sigset64_t set64;
-    } s{};
-    s.set = *set;
-    return syscall(__NR_rt_sigtimedwait, &s.set64, info, timeout, sizeof(s.set64));
-}
-
 static inline int fexecve(int fd, char* const* argv, char* const* envp) {
     syscall(__NR_execveat, fd, "", argv, envp, AT_EMPTY_PATH);
     if (errno == ENOSYS) {