diff options
Diffstat (limited to 'loader/ldt_keeper.c')
| -rw-r--r-- | loader/ldt_keeper.c | 91 |
1 files changed, 53 insertions, 38 deletions
diff --git a/loader/ldt_keeper.c b/loader/ldt_keeper.c index 8ae013c616..d71bac8ce2 100644 --- a/loader/ldt_keeper.c +++ b/loader/ldt_keeper.c @@ -4,8 +4,13 @@ * 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 */ #include "ldt_keeper.h" #include <string.h> @@ -19,6 +24,14 @@ #ifdef __linux__ #include <asm/unistd.h> #include <asm/ldt.h> +/* prototype it here, so we won't depend on kernel headers */ +#ifdef __cplusplus +extern "C" { +#endif +int modify_ldt(int func, void *ptr, unsigned long bytecount); +#ifdef __cplusplus +} +#endif #else #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__) #include <machine/segments.h> @@ -33,7 +46,7 @@ #ifdef __cplusplus extern "C" { #endif -extern int sysi86(int, void*); +int sysi86(int, void*); #ifdef __cplusplus } #endif @@ -69,20 +82,13 @@ struct modify_ldt_ldt_s { /* 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 */ #ifndef TEB_SEL_IDX -#define TEB_SEL_IDX 1 +#define TEB_SEL_IDX 17 #endif -#define TEB_SEL LDT_SEL(TEB_SEL_IDX) -/** - * - * This should be performed before we create first thread. See remarks - * for write_ldt(), linux/kernel/ldt.c. - * - */ +#define TEB_SEL LDT_SEL(TEB_SEL_IDX) -void* fs_seg = NULL; -static char* prev_struct = NULL; /** * here is a small logical problem with Restore for multithreaded programs - * in C++ we use static class for this... @@ -98,6 +104,8 @@ void Setup_FS_Segment(void) ); } +/* 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 */ @@ -130,6 +138,7 @@ static int LDT_Modify( int func, struct modify_ldt_ldt_s *ptr, return -1; } #endif +#endif #if defined(__NetBSD__) || defined(__FreeBSD__) || defined(__OpenBSD__) static void LDT_EntryToBytes( unsigned long *buffer, const struct modify_ldt_ldt_s *content ) @@ -147,31 +156,34 @@ static void LDT_EntryToBytes( unsigned long *buffer, const struct modify_ldt_ldt } #endif -void Setup_LDT_Keeper(void) +//void* fs_seg=0; + +ldt_fs_t* Setup_LDT_Keeper(void) { struct modify_ldt_ldt_s array; - int fd; int ret; + ldt_fs_t* ldt_fs = (ldt_fs_t*) malloc(sizeof(ldt_fs_t)); - if (fs_seg) - return; + if (!ldt_fs) + return NULL; - prev_struct = 0; - fd = open("/dev/zero", O_RDWR); - if(fd<0){ - perror( "Cannot open /dev/zero for READ+WRITE. Check permissions! error: " ); - return; + ldt_fs->fd = open("/dev/zero", O_RDWR); + if(ldt_fs->fd<0){ + perror( "Cannot open /dev/zero for READ+WRITE. Check permissions! error: "); + return NULL; } - fs_seg = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE, MAP_PRIVATE, - fd, 0); - if(fs_seg==(void*)-1) +// fs_seg= + ldt_fs->fs_seg = mmap(NULL, getpagesize(), PROT_READ | PROT_WRITE, MAP_PRIVATE, + ldt_fs->fd, 0); + if (ldt_fs->fs_seg == (void*)-1) { perror("ERROR: Couldn't allocate memory for fs segment"); - return; + close(ldt_fs->fd); + free(ldt_fs); + return NULL; } -// printf("fs seg %p\n", fs_seg); - *(void**)((char*)fs_seg+0x18) = fs_seg; - array.base_addr=(int)fs_seg; + *(void**)((char*)ldt_fs->fs_seg+0x18) = ldt_fs->fs_seg; + 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; @@ -180,7 +192,8 @@ void Setup_LDT_Keeper(void) 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=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"); @@ -200,7 +213,6 @@ void Setup_LDT_Keeper(void) printf("Couldn't install fs segment, expect segfault\n"); printf("Did you reconfigure the kernel with \"options USER_LDT\"?\n"); } - printf("Set_LDT\n"); } #endif /* __NetBSD__ || __FreeBSD__ || __OpenBSD__ */ @@ -223,17 +235,20 @@ void Setup_LDT_Keeper(void) Setup_FS_Segment(); - prev_struct = (char*)malloc(sizeof(char) * 8); - *(void**)array.base_addr = prev_struct; - close(fd); + ldt_fs->prev_struct = (char*)malloc(sizeof(char) * 8); + *(void**)array.base_addr = ldt_fs->prev_struct; + + return ldt_fs; } -void Restore_LDT_Keeper(void) +void Restore_LDT_Keeper(ldt_fs_t* ldt_fs) { - if (fs_seg == 0) + if (ldt_fs == NULL || ldt_fs->fs_seg == 0) return; - if (prev_struct) - free(prev_struct); - munmap((char*)fs_seg, getpagesize()); - fs_seg = 0; + if (ldt_fs->prev_struct) + free(ldt_fs->prev_struct); + munmap((char*)ldt_fs->fs_seg, getpagesize()); + ldt_fs->fs_seg = 0; + close(ldt_fs->fd); + free(ldt_fs); } |