diff options
Diffstat (limited to 'Modules/_ctypes/libffi/src/closures.c')
| -rw-r--r-- | Modules/_ctypes/libffi/src/closures.c | 660 |
1 files changed, 0 insertions, 660 deletions
diff --git a/Modules/_ctypes/libffi/src/closures.c b/Modules/_ctypes/libffi/src/closures.c deleted file mode 100644 index c7863f3d0a..0000000000 --- a/Modules/_ctypes/libffi/src/closures.c +++ /dev/null @@ -1,660 +0,0 @@ -/* ----------------------------------------------------------------------- - closures.c - Copyright (c) 2007, 2009, 2010 Red Hat, Inc. - Copyright (C) 2007, 2009, 2010 Free Software Foundation, Inc - Copyright (c) 2011 Plausible Labs Cooperative, Inc. - - Code to allocate and deallocate memory for closures. - - Permission is hereby granted, free of charge, to any person obtaining - a copy of this software and associated documentation files (the - ``Software''), to deal in the Software without restriction, including - without limitation the rights to use, copy, modify, merge, publish, - distribute, sublicense, and/or sell copies of the Software, and to - permit persons to whom the Software is furnished to do so, subject to - the following conditions: - - The above copyright notice and this permission notice shall be included - in all copies or substantial portions of the Software. - - THE SOFTWARE IS PROVIDED ``AS IS'', WITHOUT WARRANTY OF ANY KIND, - EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF - MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND - NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT - HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, - WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, - OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER - DEALINGS IN THE SOFTWARE. - ----------------------------------------------------------------------- */ - -#if defined __linux__ && !defined _GNU_SOURCE -#define _GNU_SOURCE 1 -#endif - -#include <ffi.h> -#include <ffi_common.h> - -#if !FFI_MMAP_EXEC_WRIT && !FFI_EXEC_TRAMPOLINE_TABLE -# if __gnu_linux__ && !defined(__ANDROID__) -/* This macro indicates it may be forbidden to map anonymous memory - with both write and execute permission. Code compiled when this - option is defined will attempt to map such pages once, but if it - fails, it falls back to creating a temporary file in a writable and - executable filesystem and mapping pages from it into separate - locations in the virtual memory space, one location writable and - another executable. */ -# define FFI_MMAP_EXEC_WRIT 1 -# define HAVE_MNTENT 1 -# endif -# if defined(X86_WIN32) || defined(X86_WIN64) || defined(__OS2__) -/* Windows systems may have Data Execution Protection (DEP) enabled, - which requires the use of VirtualMalloc/VirtualFree to alloc/free - executable memory. */ -# define FFI_MMAP_EXEC_WRIT 1 -# endif -#endif - -#if FFI_MMAP_EXEC_WRIT && !defined FFI_MMAP_EXEC_SELINUX -# ifdef __linux__ -/* When defined to 1 check for SELinux and if SELinux is active, - don't attempt PROT_EXEC|PROT_WRITE mapping at all, as that - might cause audit messages. */ -# define FFI_MMAP_EXEC_SELINUX 1 -# endif -#endif - -#if FFI_CLOSURES - -# if FFI_EXEC_TRAMPOLINE_TABLE - -// Per-target implementation; It's unclear what can reasonable be shared between two OS/architecture implementations. - -# elif FFI_MMAP_EXEC_WRIT /* !FFI_EXEC_TRAMPOLINE_TABLE */ - -#define USE_LOCKS 1 -#define USE_DL_PREFIX 1 -#ifdef __GNUC__ -#ifndef USE_BUILTIN_FFS -#define USE_BUILTIN_FFS 1 -#endif -#endif - -/* We need to use mmap, not sbrk. */ -#define HAVE_MORECORE 0 - -/* We could, in theory, support mremap, but it wouldn't buy us anything. */ -#define HAVE_MREMAP 0 - -/* We have no use for this, so save some code and data. */ -#define NO_MALLINFO 1 - -/* We need all allocations to be in regular segments, otherwise we - lose track of the corresponding code address. */ -#define DEFAULT_MMAP_THRESHOLD MAX_SIZE_T - -/* Don't allocate more than a page unless needed. */ -#define DEFAULT_GRANULARITY ((size_t)malloc_getpagesize) - -#if FFI_CLOSURE_TEST -/* Don't release single pages, to avoid a worst-case scenario of - continuously allocating and releasing single pages, but release - pairs of pages, which should do just as well given that allocations - are likely to be small. */ -#define DEFAULT_TRIM_THRESHOLD ((size_t)malloc_getpagesize) -#endif - -#include <sys/types.h> -#include <sys/stat.h> -#include <fcntl.h> -#include <errno.h> -#ifndef _MSC_VER -#include <unistd.h> -#endif -#include <string.h> -#include <stdio.h> -#if !defined(X86_WIN32) && !defined(X86_WIN64) -#ifdef HAVE_MNTENT -#include <mntent.h> -#endif /* HAVE_MNTENT */ -#include <sys/param.h> -#include <pthread.h> - -/* We don't want sys/mman.h to be included after we redefine mmap and - dlmunmap. */ -#include <sys/mman.h> -#define LACKS_SYS_MMAN_H 1 - -#if FFI_MMAP_EXEC_SELINUX -#include <sys/statfs.h> -#include <stdlib.h> - -static int selinux_enabled = -1; - -static int -selinux_enabled_check (void) -{ - struct statfs sfs; - FILE *f; - char *buf = NULL; - size_t len = 0; - - if (statfs ("/selinux", &sfs) >= 0 - && (unsigned int) sfs.f_type == 0xf97cff8cU) - return 1; - f = fopen ("/proc/mounts", "r"); - if (f == NULL) - return 0; - while (getline (&buf, &len, f) >= 0) - { - char *p = strchr (buf, ' '); - if (p == NULL) - break; - p = strchr (p + 1, ' '); - if (p == NULL) - break; - if (strncmp (p + 1, "selinuxfs ", 10) == 0) - { - free (buf); - fclose (f); - return 1; - } - } - free (buf); - fclose (f); - return 0; -} - -#define is_selinux_enabled() (selinux_enabled >= 0 ? selinux_enabled \ - : (selinux_enabled = selinux_enabled_check ())) - -#else - -#define is_selinux_enabled() 0 - -#endif /* !FFI_MMAP_EXEC_SELINUX */ - -/* On PaX enable kernels that have MPROTECT enable we can't use PROT_EXEC. */ -#ifdef FFI_MMAP_EXEC_EMUTRAMP_PAX -#include <stdlib.h> - -static int emutramp_enabled = -1; - -static int -emutramp_enabled_check (void) -{ - char *buf = NULL; - size_t len = 0; - FILE *f; - int ret; - f = fopen ("/proc/self/status", "r"); - if (f == NULL) - return 0; - ret = 0; - - while (getline (&buf, &len, f) != -1) - if (!strncmp (buf, "PaX:", 4)) - { - char emutramp; - if (sscanf (buf, "%*s %*c%c", &emutramp) == 1) - ret = (emutramp == 'E'); - break; - } - free (buf); - fclose (f); - return ret; -} - -#define is_emutramp_enabled() (emutramp_enabled >= 0 ? emutramp_enabled \ - : (emutramp_enabled = emutramp_enabled_check ())) -#endif /* FFI_MMAP_EXEC_EMUTRAMP_PAX */ - -#elif defined (__CYGWIN__) || defined(__INTERIX) - -#include <sys/mman.h> - -/* Cygwin is Linux-like, but not quite that Linux-like. */ -#define is_selinux_enabled() 0 - -#endif /* !defined(X86_WIN32) && !defined(X86_WIN64) */ - -#ifndef FFI_MMAP_EXEC_EMUTRAMP_PAX -#define is_emutramp_enabled() 0 -#endif /* FFI_MMAP_EXEC_EMUTRAMP_PAX */ - -/* Declare all functions defined in dlmalloc.c as static. */ -static void *dlmalloc(size_t); -static void dlfree(void*); -static void *dlcalloc(size_t, size_t) MAYBE_UNUSED; -static void *dlrealloc(void *, size_t) MAYBE_UNUSED; -static void *dlmemalign(size_t, size_t) MAYBE_UNUSED; -static void *dlvalloc(size_t) MAYBE_UNUSED; -static int dlmallopt(int, int) MAYBE_UNUSED; -static size_t dlmalloc_footprint(void) MAYBE_UNUSED; -static size_t dlmalloc_max_footprint(void) MAYBE_UNUSED; -static void** dlindependent_calloc(size_t, size_t, void**) MAYBE_UNUSED; -static void** dlindependent_comalloc(size_t, size_t*, void**) MAYBE_UNUSED; -static void *dlpvalloc(size_t) MAYBE_UNUSED; -static int dlmalloc_trim(size_t) MAYBE_UNUSED; -static size_t dlmalloc_usable_size(void*) MAYBE_UNUSED; -static void dlmalloc_stats(void) MAYBE_UNUSED; - -#if !(defined(X86_WIN32) || defined(X86_WIN64) || defined(__OS2__)) || defined (__CYGWIN__) || defined(__INTERIX) -/* Use these for mmap and munmap within dlmalloc.c. */ -static void *dlmmap(void *, size_t, int, int, int, off_t); -static int dlmunmap(void *, size_t); -#endif /* !(defined(X86_WIN32) || defined(X86_WIN64) || defined(__OS2__)) || defined (__CYGWIN__) || defined(__INTERIX) */ - -#define mmap dlmmap -#define munmap dlmunmap - -#include "dlmalloc.c" - -#undef mmap -#undef munmap - -#if !(defined(X86_WIN32) || defined(X86_WIN64) || defined(__OS2__)) || defined (__CYGWIN__) || defined(__INTERIX) - -/* A mutex used to synchronize access to *exec* variables in this file. */ -static pthread_mutex_t open_temp_exec_file_mutex = PTHREAD_MUTEX_INITIALIZER; - -/* A file descriptor of a temporary file from which we'll map - executable pages. */ -static int execfd = -1; - -/* The amount of space already allocated from the temporary file. */ -static size_t execsize = 0; - -/* Open a temporary file name, and immediately unlink it. */ -static int -open_temp_exec_file_name (char *name) -{ - int fd = mkstemp (name); - - if (fd != -1) - unlink (name); - - return fd; -} - -/* Open a temporary file in the named directory. */ -static int -open_temp_exec_file_dir (const char *dir) -{ - static const char suffix[] = "/ffiXXXXXX"; - size_t lendir = strlen (dir); - char *tempname = __builtin_alloca (lendir + sizeof (suffix)); - - if (!tempname) - return -1; - - memcpy (tempname, dir, lendir); - memcpy (tempname + lendir, suffix, sizeof (suffix)); - - return open_temp_exec_file_name (tempname); -} - -/* Open a temporary file in the directory in the named environment - variable. */ -static int -open_temp_exec_file_env (const char *envvar) -{ - const char *value = getenv (envvar); - - if (!value) - return -1; - - return open_temp_exec_file_dir (value); -} - -#ifdef HAVE_MNTENT -/* Open a temporary file in an executable and writable mount point - listed in the mounts file. Subsequent calls with the same mounts - keep searching for mount points in the same file. Providing NULL - as the mounts file closes the file. */ -static int -open_temp_exec_file_mnt (const char *mounts) -{ - static const char *last_mounts; - static FILE *last_mntent; - - if (mounts != last_mounts) - { - if (last_mntent) - endmntent (last_mntent); - - last_mounts = mounts; - - if (mounts) - last_mntent = setmntent (mounts, "r"); - else - last_mntent = NULL; - } - - if (!last_mntent) - return -1; - - for (;;) - { - int fd; - struct mntent mnt; - char buf[MAXPATHLEN * 3]; - - if (getmntent_r (last_mntent, &mnt, buf, sizeof (buf)) == NULL) - return -1; - - if (hasmntopt (&mnt, "ro") - || hasmntopt (&mnt, "noexec") - || access (mnt.mnt_dir, W_OK)) - continue; - - fd = open_temp_exec_file_dir (mnt.mnt_dir); - - if (fd != -1) - return fd; - } -} -#endif /* HAVE_MNTENT */ - -/* Instructions to look for a location to hold a temporary file that - can be mapped in for execution. */ -static struct -{ - int (*func)(const char *); - const char *arg; - int repeat; -} open_temp_exec_file_opts[] = { - { open_temp_exec_file_env, "TMPDIR", 0 }, - { open_temp_exec_file_dir, "/tmp", 0 }, - { open_temp_exec_file_dir, "/var/tmp", 0 }, - { open_temp_exec_file_dir, "/dev/shm", 0 }, - { open_temp_exec_file_env, "HOME", 0 }, -#ifdef HAVE_MNTENT - { open_temp_exec_file_mnt, "/etc/mtab", 1 }, - { open_temp_exec_file_mnt, "/proc/mounts", 1 }, -#endif /* HAVE_MNTENT */ -}; - -/* Current index into open_temp_exec_file_opts. */ -static int open_temp_exec_file_opts_idx = 0; - -/* Reset a current multi-call func, then advances to the next entry. - If we're at the last, go back to the first and return nonzero, - otherwise return zero. */ -static int -open_temp_exec_file_opts_next (void) -{ - if (open_temp_exec_file_opts[open_temp_exec_file_opts_idx].repeat) - open_temp_exec_file_opts[open_temp_exec_file_opts_idx].func (NULL); - - open_temp_exec_file_opts_idx++; - if (open_temp_exec_file_opts_idx - == (sizeof (open_temp_exec_file_opts) - / sizeof (*open_temp_exec_file_opts))) - { - open_temp_exec_file_opts_idx = 0; - return 1; - } - - return 0; -} - -/* Return a file descriptor of a temporary zero-sized file in a - writable and executable filesystem. */ -static int -open_temp_exec_file (void) -{ - int fd; - - do - { - fd = open_temp_exec_file_opts[open_temp_exec_file_opts_idx].func - (open_temp_exec_file_opts[open_temp_exec_file_opts_idx].arg); - - if (!open_temp_exec_file_opts[open_temp_exec_file_opts_idx].repeat - || fd == -1) - { - if (open_temp_exec_file_opts_next ()) - break; - } - } - while (fd == -1); - - return fd; -} - -/* Map in a chunk of memory from the temporary exec file into separate - locations in the virtual memory address space, one writable and one - executable. Returns the address of the writable portion, after - storing an offset to the corresponding executable portion at the - last word of the requested chunk. */ -static void * -dlmmap_locked (void *start, size_t length, int prot, int flags, off_t offset) -{ - void *ptr; - - if (execfd == -1) - { - open_temp_exec_file_opts_idx = 0; - retry_open: - execfd = open_temp_exec_file (); - if (execfd == -1) - return MFAIL; - } - - offset = execsize; - - if (ftruncate (execfd, offset + length)) - return MFAIL; - - flags &= ~(MAP_PRIVATE | MAP_ANONYMOUS); - flags |= MAP_SHARED; - - ptr = mmap (NULL, length, (prot & ~PROT_WRITE) | PROT_EXEC, - flags, execfd, offset); - if (ptr == MFAIL) - { - if (!offset) - { - close (execfd); - goto retry_open; - } - ftruncate (execfd, offset); - return MFAIL; - } - else if (!offset - && open_temp_exec_file_opts[open_temp_exec_file_opts_idx].repeat) - open_temp_exec_file_opts_next (); - - start = mmap (start, length, prot, flags, execfd, offset); - - if (start == MFAIL) - { - munmap (ptr, length); - ftruncate (execfd, offset); - return start; - } - - mmap_exec_offset ((char *)start, length) = (char*)ptr - (char*)start; - - execsize += length; - - return start; -} - -/* Map in a writable and executable chunk of memory if possible. - Failing that, fall back to dlmmap_locked. */ -static void * -dlmmap (void *start, size_t length, int prot, - int flags, int fd, off_t offset) -{ - void *ptr; - - assert (start == NULL && length % malloc_getpagesize == 0 - && prot == (PROT_READ | PROT_WRITE) - && flags == (MAP_PRIVATE | MAP_ANONYMOUS) - && fd == -1 && offset == 0); - -#if FFI_CLOSURE_TEST - printf ("mapping in %zi\n", length); -#endif - - if (execfd == -1 && is_emutramp_enabled ()) - { - ptr = mmap (start, length, prot & ~PROT_EXEC, flags, fd, offset); - return ptr; - } - - if (execfd == -1 && !is_selinux_enabled ()) - { - ptr = mmap (start, length, prot | PROT_EXEC, flags, fd, offset); - - if (ptr != MFAIL || (errno != EPERM && errno != EACCES)) - /* Cool, no need to mess with separate segments. */ - return ptr; - - /* If MREMAP_DUP is ever introduced and implemented, try mmap - with ((prot & ~PROT_WRITE) | PROT_EXEC) and mremap with - MREMAP_DUP and prot at this point. */ - } - - if (execsize == 0 || execfd == -1) - { - pthread_mutex_lock (&open_temp_exec_file_mutex); - ptr = dlmmap_locked (start, length, prot, flags, offset); - pthread_mutex_unlock (&open_temp_exec_file_mutex); - - return ptr; - } - - return dlmmap_locked (start, length, prot, flags, offset); -} - -/* Release memory at the given address, as well as the corresponding - executable page if it's separate. */ -static int -dlmunmap (void *start, size_t length) -{ - /* We don't bother decreasing execsize or truncating the file, since - we can't quite tell whether we're unmapping the end of the file. - We don't expect frequent deallocation anyway. If we did, we - could locate pages in the file by writing to the pages being - deallocated and checking that the file contents change. - Yuck. */ - msegmentptr seg = segment_holding (gm, start); - void *code; - -#if FFI_CLOSURE_TEST - printf ("unmapping %zi\n", length); -#endif - - if (seg && (code = add_segment_exec_offset (start, seg)) != start) - { - int ret = munmap (code, length); - if (ret) - return ret; - } - - return munmap (start, length); -} - -#if FFI_CLOSURE_FREE_CODE -/* Return segment holding given code address. */ -static msegmentptr -segment_holding_code (mstate m, char* addr) -{ - msegmentptr sp = &m->seg; - for (;;) { - if (addr >= add_segment_exec_offset (sp->base, sp) - && addr < add_segment_exec_offset (sp->base, sp) + sp->size) - return sp; - if ((sp = sp->next) == 0) - return 0; - } -} -#endif - -#endif /* !(defined(X86_WIN32) || defined(X86_WIN64) || defined(__OS2__)) || defined (__CYGWIN__) || defined(__INTERIX) */ - -/* Allocate a chunk of memory with the given size. Returns a pointer - to the writable address, and sets *CODE to the executable - corresponding virtual address. */ -void * -ffi_closure_alloc (size_t size, void **code) -{ - void *ptr; - - if (!code) - return NULL; - - ptr = dlmalloc (size); - - if (ptr) - { - msegmentptr seg = segment_holding (gm, ptr); - - *code = add_segment_exec_offset (ptr, seg); - } - - return ptr; -} - -/* Release a chunk of memory allocated with ffi_closure_alloc. If - FFI_CLOSURE_FREE_CODE is nonzero, the given address can be the - writable or the executable address given. Otherwise, only the - writable address can be provided here. */ -void -ffi_closure_free (void *ptr) -{ -#if FFI_CLOSURE_FREE_CODE - msegmentptr seg = segment_holding_code (gm, ptr); - - if (seg) - ptr = sub_segment_exec_offset (ptr, seg); -#endif - - dlfree (ptr); -} - - -#if FFI_CLOSURE_TEST -/* Do some internal sanity testing to make sure allocation and - deallocation of pages are working as intended. */ -int main () -{ - void *p[3]; -#define GET(idx, len) do { p[idx] = dlmalloc (len); printf ("allocated %zi for p[%i]\n", (len), (idx)); } while (0) -#define PUT(idx) do { printf ("freeing p[%i]\n", (idx)); dlfree (p[idx]); } while (0) - GET (0, malloc_getpagesize / 2); - GET (1, 2 * malloc_getpagesize - 64 * sizeof (void*)); - PUT (1); - GET (1, 2 * malloc_getpagesize); - GET (2, malloc_getpagesize / 2); - PUT (1); - PUT (0); - PUT (2); - return 0; -} -#endif /* FFI_CLOSURE_TEST */ -# else /* ! FFI_MMAP_EXEC_WRIT */ - -/* On many systems, memory returned by malloc is writable and - executable, so just use it. */ - -#include <stdlib.h> - -void * -ffi_closure_alloc (size_t size, void **code) -{ - if (!code) - return NULL; - - return *code = malloc (size); -} - -void -ffi_closure_free (void *ptr) -{ - free (ptr); -} - -# endif /* ! FFI_MMAP_EXEC_WRIT */ -#endif /* FFI_CLOSURES */ |