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mirror of https://github.com/mpv-player/mpv synced 2024-11-14 22:48:35 +01:00
mpv/loader/ldt_keeper.c
Uoti Urpala 5234c72e28 Restore collapsed whitespace in output messages
For some reason commit e306174952, which
replaced translation macro names with the corresponding English
strings, also collapsed multiple consecutive space characters into
one. Change most of these back. In a couple of cases the amount of
whitespace is important for alignment, and for the rest it at least
keeps the strings closer to the existing translations.
2010-03-07 21:34:54 +02:00

302 lines
8.0 KiB
C

/**
* !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
* This file MUST be in main library because LDT must
* be modified before program creates first thread
* - avifile includes this file from C++ code
* and initializes it at the start of player!
* it might sound like a hack and it really is - but
* as aviplay is deconding video with more than just one
* thread currently it's necessary to do it this way
* this might change in the future
*/
/* applied some modification to make make our xine friend more happy */
/*
* Modified for use with MPlayer, detailed changelog at
* http://svn.mplayerhq.hu/mplayer/trunk/
*/
#include "config.h"
#include "ldt_keeper.h"
#include <string.h>
#include <stdlib.h>
#include <errno.h>
#include <fcntl.h>
#ifdef HAVE_SYS_MMAN_H
#include <sys/mman.h>
#else
#include "osdep/mmap.h"
#endif
#include <sys/types.h>
#include <stdio.h>
#include <unistd.h>
#include "osdep/mmap_anon.h"
#include "mp_msg.h"
#include "help_mp.h"
#ifdef __linux__
#include <asm/unistd.h>
#include <asm/ldt.h>
// 2.5.xx+ calls this user_desc:
#include <linux/version.h>
#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,47)
#define modify_ldt_ldt_s user_desc
#endif
/* prototype it here, so we won't depend on kernel headers */
#ifdef __cplusplus
extern "C" {
#endif
/// declare modify_ldt with the _syscall3 macro for older glibcs
#if defined(__GLIBC__) && (__GLIBC__ < 2 || (__GLIBC__ == 2 && __GLIBC_MINOR__ == 0))
_syscall3( int, modify_ldt, int, func, void *, ptr, unsigned long, bytecount );
#else
int modify_ldt(int func, void *ptr, unsigned long bytecount);
#endif
#ifdef __cplusplus
}
#endif
#else
#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__)
#include <machine/segments.h>
#include <machine/sysarch.h>
#endif
#if defined(__APPLE__)
#include <architecture/i386/table.h>
#include <i386/user_ldt.h>
#endif
#ifdef __svr4__
#include <sys/segment.h>
#include <sys/sysi86.h>
/* solaris x86: add missing prototype for sysi86(), but only when sysi86(int, void*) is known to be valid */
#ifdef HAVE_SYSI86_iv
#ifdef __cplusplus
extern "C" {
#endif
int sysi86(int, void*);
#ifdef __cplusplus
}
#endif
#endif
#ifndef NUMSYSLDTS /* SunOS 2.5.1 does not define NUMSYSLDTS */
#define NUMSYSLDTS 6 /* Let's hope the SunOS 5.8 value is OK */
#endif
#define TEB_SEL_IDX NUMSYSLDTS
#endif
#define LDT_ENTRIES 8192
#define LDT_ENTRY_SIZE 8
#pragma pack(4)
struct modify_ldt_ldt_s {
unsigned int entry_number;
unsigned long base_addr;
unsigned int limit;
unsigned int seg_32bit:1;
unsigned int contents:2;
unsigned int read_exec_only:1;
unsigned int limit_in_pages:1;
unsigned int seg_not_present:1;
unsigned int useable:1;
};
#define MODIFY_LDT_CONTENTS_DATA 0
#define MODIFY_LDT_CONTENTS_STACK 1
#define MODIFY_LDT_CONTENTS_CODE 2
#endif
/* user level (privilege level: 3) ldt (1<<2) segment selector */
#define LDT_SEL(idx) ((idx) << 3 | 1 << 2 | 3)
/* i got this value from wine sources, it's the first free LDT entry */
#if (defined(__APPLE__) || defined(__FreeBSD__)) && defined(LDT_AUTO_ALLOC)
#define TEB_SEL_IDX LDT_AUTO_ALLOC
#define USE_LDT_AA
#endif
#ifndef TEB_SEL_IDX
#define TEB_SEL_IDX 17
#endif
static unsigned int fs_ldt = TEB_SEL_IDX;
/**
* here is a small logical problem with Restore for multithreaded programs -
* in C++ we use static class for this...
*/
#ifdef __cplusplus
extern "C"
#endif
void Setup_FS_Segment(void)
{
unsigned int ldt_desc = LDT_SEL(fs_ldt);
__asm__ volatile(
"movl %0,%%eax; movw %%ax, %%fs" : : "r" (ldt_desc)
:"eax"
);
}
/* we don't need this - use modify_ldt instead */
#if 0
#ifdef __linux__
/* XXX: why is this routine from libc redefined here? */
/* NOTE: the redefined version ignores the count param, count is hardcoded as 16 */
static int LDT_Modify( int func, struct modify_ldt_ldt_s *ptr,
unsigned long count )
{
int res;
#ifdef __PIC__
__asm__ volatile( "pushl %%ebx\n\t"
"movl %2,%%ebx\n\t"
"int $0x80\n\t"
"popl %%ebx"
: "=a" (res)
: "0" (__NR_modify_ldt),
"r" (func),
"c" (ptr),
"d"(16)//sizeof(*ptr) from kernel point of view
:"esi" );
#else
__asm__ volatile("int $0x80"
: "=a" (res)
: "0" (__NR_modify_ldt),
"b" (func),
"c" (ptr),
"d"(16)
:"esi");
#endif /* __PIC__ */
if (res >= 0) return res;
errno = -res;
return -1;
}
#endif
#endif
#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) || defined(__APPLE__)
static void LDT_EntryToBytes( unsigned long *buffer, const struct modify_ldt_ldt_s *content )
{
*buffer++ = ((content->base_addr & 0x0000ffff) << 16) |
(content->limit & 0x0ffff);
*buffer = (content->base_addr & 0xff000000) |
((content->base_addr & 0x00ff0000)>>16) |
(content->limit & 0xf0000) |
(content->contents << 10) |
((content->read_exec_only == 0) << 9) |
((content->seg_32bit != 0) << 22) |
((content->limit_in_pages != 0) << 23) |
0xf000;
}
#endif
void* fs_seg=0;
ldt_fs_t* Setup_LDT_Keeper(void)
{
struct modify_ldt_ldt_s array;
int ret;
ldt_fs_t* ldt_fs = (ldt_fs_t*) malloc(sizeof(ldt_fs_t));
if (!ldt_fs)
return NULL;
#ifdef __APPLE__
if (getenv("DYLD_BIND_AT_LAUNCH") == NULL)
mp_tmsg(MSGT_LOADER, MSGL_WARN, "WARNING: Attempting to use DLL codecs but environment variable\n DYLD_BIND_AT_LAUNCH not set. This will likely crash.\n");
#endif /* __APPLE__ */
fs_seg=
ldt_fs->fs_seg = mmap_anon(NULL, getpagesize(), PROT_READ | PROT_WRITE, MAP_PRIVATE, 0);
if (ldt_fs->fs_seg == (void*)-1)
{
perror("ERROR: Couldn't allocate memory for fs segment");
free(ldt_fs);
return NULL;
}
*(void**)((char*)ldt_fs->fs_seg+0x18) = ldt_fs->fs_seg;
memset(&array, 0, sizeof(array));
array.base_addr=(int)ldt_fs->fs_seg;
array.entry_number=TEB_SEL_IDX;
array.limit=array.base_addr+getpagesize()-1;
array.seg_32bit=1;
array.read_exec_only=0;
array.seg_not_present=0;
array.contents=MODIFY_LDT_CONTENTS_DATA;
array.limit_in_pages=0;
#ifdef __linux__
//ret=LDT_Modify(0x1, &array, sizeof(struct modify_ldt_ldt_s));
ret=modify_ldt(0x1, &array, sizeof(struct modify_ldt_ldt_s));
if(ret<0)
{
perror("install_fs");
printf("Couldn't install fs segment, expect segfault\n");
}
#endif /*linux*/
#if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) || defined(__APPLE__)
{
unsigned long d[2];
LDT_EntryToBytes( d, &array );
#ifdef USE_LDT_AA
ret = i386_set_ldt(LDT_AUTO_ALLOC, (union descriptor *)d, 1);
array.entry_number = ret;
fs_ldt = ret;
#else
ret = i386_set_ldt(array.entry_number, (union descriptor *)d, 1);
#endif
if (ret < 0)
{
perror("install_fs");
printf("Couldn't install fs segment, expect segfault\n");
printf("Did you reconfigure the kernel with \"options USER_LDT\"?\n");
#ifdef __OpenBSD__
printf("On newer OpenBSD systems did you set machdep.userldt to 1?\n");
#endif
}
}
#endif /* __NetBSD__ || __FreeBSD__ || __OpenBSD__ || __DragonFly__ || __APPLE__ */
#if defined(__svr4__)
{
struct ssd ssd;
ssd.sel = LDT_SEL(TEB_SEL_IDX);
ssd.bo = array.base_addr;
ssd.ls = array.limit - array.base_addr;
ssd.acc1 = ((array.read_exec_only == 0) << 1) |
(array.contents << 2) |
0xf0; /* P(resent) | DPL3 | S */
ssd.acc2 = 0x4; /* byte limit, 32-bit segment */
if (sysi86(SI86DSCR, &ssd) < 0) {
perror("sysi86(SI86DSCR)");
printf("Couldn't install fs segment, expect segfault\n");
}
}
#endif
Setup_FS_Segment();
ldt_fs->prev_struct = malloc(8);
*(void**)array.base_addr = ldt_fs->prev_struct;
return ldt_fs;
}
void Restore_LDT_Keeper(ldt_fs_t* ldt_fs)
{
if (ldt_fs == NULL || ldt_fs->fs_seg == 0)
return;
if (ldt_fs->prev_struct)
free(ldt_fs->prev_struct);
munmap((char*)ldt_fs->fs_seg, getpagesize());
ldt_fs->fs_seg = 0;
free(ldt_fs);
}