Files
2ine-tms34010/lx_loader.c
T

2226 lines
84 KiB
C

/**
* 2ine; an OS/2 emulator for Linux.
*
* Please see the file LICENSE.txt in the source's root directory.
*
* This file written by Ryan C. Gordon.
*/
#define _GNU_SOURCE 1
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <stdint.h>
#include <errno.h>
#include <sys/mman.h>
#include <assert.h>
#include <dlfcn.h>
#include <dirent.h>
#include <pthread.h>
#include <signal.h>
#include <ucontext.h>
// 16-bit selector kernel nonsense...
#include <sys/syscall.h>
#include <sys/types.h>
#include <asm/ldt.h>
#include "lx_loader.h"
static LxLoaderState _GLoaderState;
static LxLoaderState *GLoaderState = &_GLoaderState;
// !!! FIXME: move this into an lx_common.c file.
static int sanityCheckLxModule(uint8 **_exe, uint32 *_exelen)
{
if (*_exelen < 196) {
fprintf(stderr, "not an OS/2 LX module\n");
return 0;
}
const uint32 header_offset = *((uint32 *) (*_exe + 0x3C));
//printf("header offset is %u\n", (uint) header_offset);
if ((header_offset + sizeof (LxHeader)) >= *_exelen) {
fprintf(stderr, "not an OS/2 LX module\n");
return 0;
}
*_exe += header_offset; // skip the DOS stub, etc.
*_exelen -= header_offset;
const LxHeader *lx = (const LxHeader *) *_exe;
if ((lx->magic_l != 'L') || (lx->magic_x != 'X')) {
fprintf(stderr, "not an OS/2 LX module\n");
return 0;
}
if ((lx->byte_order != 0) || (lx->word_order != 0)) {
fprintf(stderr, "Program is not little-endian!\n");
return 0;
}
if (lx->lx_version != 0) {
fprintf(stderr, "Program is unknown LX module version (%u)\n", (uint) lx->lx_version);
return 0;
}
if (lx->cpu_type > 3) { // 1==286, 2==386, 3==486
fprintf(stderr, "Program needs unknown CPU type (%u)\n", (uint) lx->cpu_type);
return 0;
}
if (lx->os_type != 1) { // 1==OS/2, others: dos4, windows, win386, unknown.
fprintf(stderr, "Program needs unknown OS type (%u)\n", (uint) lx->os_type);
return 0;
}
if (lx->page_size != 4096) {
fprintf(stderr, "Program page size isn't 4096 (%u)\n", (uint) lx->page_size);
return 0;
}
if (lx->module_flags & 0x2000) {
fprintf(stderr, "Module is flagged as not-loadable\n");
return 0;
}
// !!! FIXME: check if EIP and ESP are non-zero vs per-process library bits, etc.
return 1;
} // sanityCheckLxModule
static char *makeOS2Path(const char *fname)
{
char *full = realpath(fname, NULL);
if (!full)
return NULL;
char *retval = (char *) malloc(strlen(full) + 3);
if (!retval)
return NULL;
retval[0] = 'C';
retval[1] = ':';
strcpy(retval + 2, full);
free(full);
for (char *ptr = retval + 2; *ptr; ptr++) {
if (*ptr == '/')
*ptr = '\\';
} // for
return retval;
} // makeOS2Path
// based on case-insensitive search code from PhysicsFS:
// https://icculus.org/physfs/
// It's also zlib-licensed, plus I wrote it. :) --ryan.
// !!! FIXME: this doesn't work as-is for UTF-8 case folding, since string
// !!! FIXNE: length can change!
static int locateOneElement(char *buf)
{
if (access(buf, F_OK) == 0)
return 1; // quick rejection: exists in current case.
DIR *dirp;
char *ptr = strrchr(buf, '/'); // find entry at end of path.
if (ptr == NULL) {
dirp = opendir(".");
ptr = buf;
} else if (ptr == buf) {
dirp = opendir("/");
} else {
*ptr = '\0';
dirp = opendir(buf);
*ptr = '/';
ptr++; // point past dirsep to entry itself.
} // else
for (struct dirent *dent = readdir(dirp); dent; dent = readdir(dirp)) {
if (strcasecmp(dent->d_name, ptr) == 0) {
strcpy(ptr, dent->d_name); // found a match. Overwrite with this case.
closedir(dirp);
return 1;
} // if
} // for
// no match at all...
closedir(dirp);
return 0;
} // locateOneElement
static int locatePathCaseInsensitive(char *buf)
{
int rc;
char *ptr = buf;
if (*ptr == '\0')
return 0; // Uh...I guess that's success?
if (access(buf, F_OK) == 0)
return 0; // quick rejection: exists in current case.
while ( (ptr = strchr(ptr + 1, '/')) != NULL ) {
*ptr = '\0'; // block this path section off
rc = locateOneElement(buf);
*ptr = '/'; // restore path separator
if (!rc)
return -2; // missing element in path.
} // while
// check final element...
return locateOneElement(buf) ? 0 : -1;
} // locatePathCaseInsensitive
static char *makeUnixPath(const char *os2path, uint32 *err)
{
if ((strcasecmp(os2path, "NUL") == 0) || (strcasecmp(os2path, "\\DEV\\NUL") == 0))
os2path = "/dev/null";
// !!! FIXME: emulate other OS/2 device names (CON, etc).
//else if (strcasecmp(os2path, "CON") == 0)
else {
char drive = os2path[0];
if ((drive >= 'a') && (drive <= 'z'))
drive += 'A' - 'a';
if ((drive >= 'A') && (drive <= 'Z')) {
if (os2path[1] == ':') { // it's a drive letter.
if (drive == 'C')
os2path += 2; // skip "C:" if it's there.
else {
*err = 26; //ERROR_NOT_DOS_DISK;
return NULL;
} // else
} // if
} // if
} // else
const size_t len = strlen(os2path);
char *retval = (char *) malloc(len + 1);
if (!retval) {
*err = 8; //ERROR_NOT_ENOUGH_MEMORY;
return NULL;
} // else
strcpy(retval, os2path);
for (char *ptr = strchr(retval, '\\'); ptr; ptr = strchr(ptr + 1, '\\'))
*ptr = '/'; // convert to Unix-style path separators.
locatePathCaseInsensitive(retval);
return retval;
} // makeUnixPath
/* this algorithm is from lxlite 138u. */
static int decompressExePack2(uint8 *dst, const uint32 dstlen, const uint8 *src, const uint32 srclen)
{
uint32 sOf = 0;
uint32 dOf = 0;
uint32 bOf = 0;
uint32 b1 = 0;
uint32 b2 = 0;
#define SRCAVAIL(n) ((sOf + (n)) <= srclen)
#define DSTAVAIL(n) ((dOf + (n)) <= dstlen)
do {
if (!SRCAVAIL(1))
break;
b1 = src[sOf];
switch (b1 & 3) {
case 0:
if (b1 == 0) {
if (SRCAVAIL(2)) {
if (src[sOf + 1] == 0) {
sOf += 2;
break;
} else if (SRCAVAIL(3) && DSTAVAIL(src[sOf + 1])) {
memset(dst + dOf, src[sOf + 2], src[sOf + 1]);
sOf += 3;
dOf += src[sOf - 2];
} else {
return 0;
}
} else {
return 0;
}
} else if (SRCAVAIL((b1 >> 2) + 1) && DSTAVAIL(b1 >> 2)) {
memcpy(dst + dOf, src + (sOf + 1), b1 >> 2);
dOf += b1 >> 2;
sOf += (b1 >> 2) + 1;
} else {
return 0;
}
break;
case 1:
if (!SRCAVAIL(2))
return 0;
bOf = (*((const uint16 *) (src + sOf))) >> 7;
b2 = ((b1 >> 4) & 7) + 3;
b1 = ((b1 >> 2) & 3);
sOf += 2;
if (SRCAVAIL(b1) && DSTAVAIL(b1 + b2) && (dOf + b1 - bOf >= 0)) {
memcpy(dst + dOf, src + sOf, b1);
dOf += b1;
sOf += b1;
memmove(dst + dOf, dst + (dOf - bOf), b2);
dOf += b2;
} else {
return 0;
} // else
break;
case 2:
if (!SRCAVAIL(2))
return 0;
bOf = (*((const uint16 *) (src + sOf))) >> 4;
b1 = ((b1 >> 2) & 3) + 3;
if (DSTAVAIL(b1) && (dOf - bOf >= 0)) {
memmove(dst + dOf, dst + (dOf - bOf), b1);
dOf += b1;
sOf += 2;
} else {
return 0;
} // else
break;
case 3:
if (!SRCAVAIL(3))
return 0;
b2 = ((*((const uint16 *) (src + sOf))) >> 6) & 0x3F;
b1 = (src[sOf] >> 2) & 0x0F;
bOf = (*((const uint16 *) (src + (sOf + 1)))) >> 4;
sOf += 3;
if (SRCAVAIL(b1) && DSTAVAIL(b1 + b2) && (dOf + b1 - bOf >= 0))
{
memcpy(dst + dOf, src + sOf, b1);
dOf += b1;
sOf += b1;
memmove(dst + dOf, dst + (dOf - bOf), b2);
dOf += b2;
} else {
return 0;
} // else
break;
} // switch
} while (dOf < dstlen);
#undef SRCAVAIL
#undef DSTAVAIL
// pad out the rest of the page with zeroes.
if ((dstlen - dOf) > 0)
memset(dst + dOf, '\0', dstlen - dOf);
return 1;
} // decompressExePack2
static int decompressIterated(uint8 *dst, uint32 dstlen, const uint8 *src, uint32 srclen)
{
while (srclen) {
if (srclen < 4)
return 0;
const uint16 iterations = *((uint16 *) src); src += 2;
const uint16 len = *((uint16 *) src); src += 2;
srclen -= 4;
if (dstlen < (iterations * len))
return 0;
else if (srclen < len)
return 0;
for (uint16 i = 0; i < iterations; i++) {
memcpy(dst, src, len);
dst += len;
dstlen -= len;
} // for
src += len;
srclen -= len;
} // while
// pad out the rest of the page with zeroes.
if (dstlen > 0)
memset(dst, '\0', dstlen);
return 1;
} // decompressIterated
// !!! FIXME: mutex this
static int allocateSelector(const uint16 selector, const int pages, const uint32 addr, const unsigned int contents, const int is32bit)
{
assert(selector < (sizeof (GLoaderState->ldt) / sizeof (GLoaderState->ldt[0])));
if (GLoaderState->ldt[selector])
return 0; // already in use.
//const int expand_down = (contents == MODIFY_LDT_CONTENTS_STACK);
struct user_desc entry;
entry.entry_number = (unsigned int) selector;
entry.base_addr = (unsigned int) addr; //(expand_down ? (addr + 0x10000) : addr);
entry.limit = pages; //expand_down ? 0 : 16;
entry.seg_32bit = is32bit;
entry.contents = contents;
entry.read_exec_only = 0;
entry.limit_in_pages = 1;
entry.seg_not_present = 0;
entry.useable = 1;
if (syscall(SYS_modify_ldt, 1, &entry, sizeof (entry)) != 0)
return 0;
GLoaderState->ldt[selector] = addr;
return 1;
} // allocateSelector
// !!! FIXME: mutex this
static int findSelector(const uint32 _addr, uint16 *outselector, uint16 *outoffset, int iscode)
{
uint32 addr = _addr;
if (addr < 4096)
return 0; // we won't map the NULL page.
const uint32 *ldt = GLoaderState->ldt;
int available = -1;
int preferred = -1;
// optimize for the case where we need a selector that happens to be in tiled memory,
// since it's fast to look up.
if (addr < (1024 * 1024 * 512)) {
const uint16 idx = (uint16) (addr >> 16);
const uint32 tile = ldt[idx];
if (tile == 0) {
preferred = available = idx; // we can use this piece.
} else if ((tile <= addr) && ((tile + 0x10000) > addr)) {
*outselector = idx;
*outoffset = (uint16) (addr - tile);
//printf("SELECTOR: found tiled selector 0x%X for address %p\n", (uint) idx, (void *) addr);
return 1; // already allocated to this address.
} // if
} // if
for (int i = 0; i < (sizeof (GLoaderState->ldt) / sizeof (GLoaderState->ldt[0])); i++) {
const uint32 tile = ldt[i];
if (tile == 0)
available = i;
else if ((tile <= addr) && ((tile + 0x10000) > addr)) {
*outselector = (uint16) i;
*outoffset = (uint16) (addr - tile);
//printf("SELECTOR: found existing selector 0x%X for address %p\n", (uint) i, (void *) addr);
return 1; // already allocated to this address.
} // else if
} // for
// nothing allocated to this address so far. Try to allocate something.
if (available == -1) {
fprintf(stderr, "Uhoh, we've run out of LDT selectors! Probably about to crash...\n"); fflush(stderr);
return 0; // uh oh, out of selectors!
} // if
// decide if there is code or data mapped here. If there's an OS/2 API to
// change page permissions, we'll need to update the mapping and our state.
for (LxModule *lxmod = GLoaderState->loaded_modules; (iscode == -1) && lxmod; lxmod = lxmod->next) {
LxMmaps *mmaps = lxmod->mmaps;
for (uint32 i = 0; i < lxmod->lx.module_num_objects; i++, mmaps++) {
const size_t lo = (size_t) mmaps->addr;
const size_t hi = lo + mmaps->size;
if ((addr >= lo) && (addr <= hi)) {
iscode = ((mmaps->prot & PROT_EXEC) != 0);
break;
} // if
} // for
} // for
if (iscode == -1) {
iscode = 0;
}
const uint32 diff = addr % 0x10000;
addr -= diff; // make sure we start on a 64k border.
const uint16 selector = (uint16) (preferred != -1) ? preferred : available;
//printf("setting up LDT mapping for %s at selector %u\n", iscode ? "code" : "data", (unsigned int) selector);
if (!allocateSelector(selector, 16, addr, iscode ? MODIFY_LDT_CONTENTS_CODE : MODIFY_LDT_CONTENTS_DATA, 0)) {
fprintf(stderr, "Uhoh, we've failed to allocate LDT selector %u! Probably about to crash...\n", (uint) selector); fflush(stderr);
return 0;
} // if
//printf("SELECTOR: allocated selector 0x%X for address %p\n", (uint) selector, (void *) addr);
*outselector = selector;
*outoffset = (uint16) diff;
return 1;
} // findSelector
// !!! FIXME: mutex this
static void freeSelector(const uint16 selector)
{
assert(selector < (sizeof (GLoaderState->ldt) / sizeof (GLoaderState->ldt[0])));
if (!GLoaderState->ldt[selector])
return; // already free.
struct user_desc entry;
memset(&entry, '\0', sizeof (entry));
entry.entry_number = (unsigned int) selector;
entry.read_exec_only = 1;
entry.seg_not_present = 1;
if (syscall(SYS_modify_ldt, 1, &entry, sizeof (entry)) != 0)
return; // oh well.
GLoaderState->ldt[selector] = 0;
} // freeSelector
static void *convert1616to32(const uint32 addr1616)
{
if (addr1616 == 0)
return NULL;
const uint16 selector = (uint16) (addr1616 >> 19); // slide segment down, and shift out control bits.
const uint16 offset = (uint16) (addr1616 % 0x10000); // all our LDT segments start at 64k boundaries (at the moment!).
assert(GLoaderState->ldt[selector] != 0);
//printf("convert1616to32: 0x%X -> %p\n", (uint) addr1616, (void *) (size_t) (GLoaderState->ldt[selector] + offset));
return (void *) (size_t) (GLoaderState->ldt[selector] + offset);
} // convert1616to32
static uint32 convert32to1616(void *addr32)
{
if (addr32 == NULL)
return 0;
uint16 selector = 0;
uint16 offset = 0;
if (!findSelector((uint32) addr32, &selector, &offset, -1)) {
fprintf(stderr, "Uhoh, ran out of LDT entries?!\n");
return 0; // oh well, crash, probably.
} // if
//printf("selector: 0x%X\n", (uint) selector);
selector = (selector << 3) | 7;
//printf("shifted selector: 0x%X\n", (uint) selector);
return (((uint32)selector) << 16) | ((uint32) offset);
} // convert32to1616
// EMX (and probably many other things) occasionally has to call a 16-bit
// system API, and assumes its stack is tiled in the LDT; it'll just shift
// the stack pointer and use it as a stack segment for the 16-bit call
// without calling DosFlatToSel(). So we tile the main thread's stack and
// pray that covers it. If we have to tile _every_ thread's stack, we can do
// that later.
// !!! FIXME: if we do this for secondary thread stacks, we'll need to mutex this.
static void initOs2StackSegments(uint32 addr, uint32 stacklen, const int deinit)
{
//printf("base == %p, stacklen == %u\n", (void*)addr, (uint) stacklen);
const uint32 diff = addr % 0x10000;
addr -= diff; // make sure we start on a 64k border.
stacklen += diff; // make sure we start on a 64k border.
// We fill in LDT tiles for the entire stack (EMX, etc, assume this will work).
if (stacklen % 0x10000) // pad this out to 64k
stacklen += 0x10000 - (stacklen % 0x10000);
// !!! FIXME: do we have to allocate these backwards? (stack grows down).
while (stacklen) {
//printf("Allocating selector 0x%X for stack %p ... \n", (uint) (addr >> 16), (void *) addr);
if (deinit) {
freeSelector((uint16) (addr >> 16));
} else {
if (!allocateSelector((uint16) (addr >> 16), 16, addr, MODIFY_LDT_CONTENTS_DATA, 0)) {
FIXME("uhoh, couldn't set up an LDT entry for a stack segment! Might crash later!");
} // if
} // else
stacklen -= 0x10000;
addr += 0x10000;
} // while
} // initOs2StackSegments
// OS/2 threads keep their Thread Information Block at FS:0x0000, so we have
// to ask the Linux kernel to screw around with 16-bit selectors on our
// behalf so we don't crash out when apps try to access it directly.
// OS/2 provides a C-callable API to obtain the (32-bit linear!) TIB address
// without going directly to the FS register, but lots of programs (including
// the EMX runtime) touch the register directly, so we have to deal with it.
// You must call this once for each thread that will go into LX land, from
// that thread, as soon as possible after starting.
static uint16 initOs2Tib(uint8 *tibspace, void *_topOfStack, const size_t stacklen, const uint32 tid)
{
uint8 *topOfStack = (uint8 *) _topOfStack;
LxTIB *tib = (LxTIB *) tibspace;
LxTIB2 *tib2 = (LxTIB2 *) (tib + 1);
FIXME("This is probably 50% wrong");
tib->tib_pexchain = NULL;
tib->tib_pstack = topOfStack - stacklen;
tib->tib_pstacklimit = (void *) topOfStack;
tib->tib_ptib2 = tib2;
tib->tib_version = 20; // !!! FIXME
tib->tib_ordinal = 79; // !!! FIXME
tib2->tib2_ultid = tid;
tib2->tib2_ulpri = 512;
tib2->tib2_version = 20;
tib2->tib2_usMCCount = 0;
tib2->tib2_fMCForceFlag = 0;
// !!! FIXME: I barely know what I'm doing here, this could all be wrong.
struct user_desc entry;
entry.entry_number = -1;
entry.base_addr = (unsigned int) ((size_t)tib);
entry.limit = LXTIBSIZE;
entry.seg_32bit = 1;
entry.contents = MODIFY_LDT_CONTENTS_DATA;
entry.read_exec_only = 0;
entry.limit_in_pages = 0;
entry.seg_not_present = 0;
entry.useable = 1;
const long rc = syscall(SYS_set_thread_area, &entry);
assert(rc == 0); FIXME("this can legit fail, though!");
// The "<< 3 | 3" makes this a GDT selector at ring 3 permissions.
// If this did "| 7" instead of "| 3", it'd be an LDT selector.
// Use findSelector() or allocateSelector() for LDT entries, though!
const unsigned int segment = (entry.entry_number << 3) | 3;
__asm__ __volatile__ ( "movw %%ax, %%fs \n\t" : : "a" (segment) );
return (uint16) entry.entry_number;
} // initOs2Tib
static void deinitOs2Tib(const uint16 selector)
{
// !!! FIXME: I barely know what I'm doing here, this could all be wrong.
struct user_desc entry;
memset(&entry, '\0', sizeof (entry));
entry.entry_number = selector;
entry.read_exec_only = 1;
entry.seg_not_present = 1;
const long rc = syscall(SYS_set_thread_area, &entry);
assert(rc == 0); FIXME("this can legit fail, though!");
} // deinitOs2Tib
static void freeLxModule(LxModule *lxmod);
static __attribute__((noreturn)) void terminate(const uint32 exitcode)
{
// free the actual .exe
freeLxModule(GLoaderState->main_module);
// clear out anything that is still loaded...
// presumably everything in the loaded_modules list is sorted in order
// of dependency, since we prepend the newest loads to the front of the
// list, and anything a load depends on gets listed before the dependent
// module, pushing it futher down.
// if this doesn't work out, maybe just run everything's termination code
// and free everything after there's nothing left to run.
while (GLoaderState->loaded_modules) {
LxModule *lxmod = GLoaderState->loaded_modules;
lxmod->refcount = 1; // force it to free now.
freeLxModule(lxmod);
} // while
// OS/2's docs say this only keeps the lower 16 bits of exitcode.
// !!! FIXME: ...but Unix only keeps the lowest 8 bits. Will have to
// !!! FIXME: tapdance to pass larger values back to OS/2 parent processes.
if (exitcode > 255)
FIXME("deal with process exit codes > 255. We clamped this one!");
_exit((int) (exitcode & 0xFF));
} // terminate
static __attribute__((noreturn)) void endLxProcess(const uint32 exitcode)
{
if (GLoaderState->dosExit)
GLoaderState->dosExit(1, exitcode); // let exit lists run. Should call terminate!
terminate(exitcode); // just in case.
} // endLxProcess
static void missingEntryPointCalled(const char *module, const char *entry)
{
fflush(stdout);
fflush(stderr);
fprintf(stderr, "\n\nMissing entry point '%s' in module '%s'! Aborting.\n\n\n", entry, module);
//STUBBED("output backtrace");
fflush(stderr);
terminate(1);
} // missingEntryPointCalled
static void *generateMissingTrampoline(const char *_module, const char *_entry)
{
static void *page = NULL;
static uint32 pageused = 0;
static uint32 pagesize = 0;
if (pagesize == 0)
pagesize = getpagesize();
if ((!page) || ((pagesize - pageused) < 32))
{
if (page)
mprotect(page, pagesize, PROT_READ | PROT_EXEC);
page = mmap(NULL, pagesize, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
pageused = 0;
} // if
void *trampoline = page + pageused;
char *ptr = (char *) trampoline;
char *module = strdup(_module);
char *entry = strdup(_entry);
*(ptr++) = 0x55; // pushl %ebp
*(ptr++) = 0x89; // movl %esp,%ebp
*(ptr++) = 0xE5; // ...movl %esp,%ebp
*(ptr++) = 0x68; // pushl immediate
memcpy(ptr, &entry, sizeof (char *));
ptr += sizeof (uint32);
*(ptr++) = 0x68; // pushl immediate
memcpy(ptr, &module, sizeof (char *));
ptr += sizeof (uint32);
*(ptr++) = 0xB8; // movl immediate to %eax
const void *fn = missingEntryPointCalled;
memcpy(ptr, &fn, sizeof (void *));
ptr += sizeof (void *);
*(ptr++) = 0xFF; // call absolute in %eax.
*(ptr++) = 0xD0; // ...call absolute in %eax.
const uint32 trampoline_len = (uint32) (ptr - ((char *) trampoline));
assert(trampoline_len <= 32);
pageused += trampoline_len;
if (pageused % 4) // keep these aligned to 32 bits.
pageused += (4 - (pageused % 4));
//printf("Generated trampoline %p for module '%s' export '%s'\n", trampoline, module, entry);
return trampoline;
} // generateMissingTrampoline
static void *generateMissingTrampoline16(const char *_module, const char *_entry, const LxExport **_lxexp)
{
static void *page = NULL;
static uint32 pageused = 0;
const uint32 pagesize = 0x10000;
static uint16 selector = 0xFFFF;
if ((!page) || ((pagesize - pageused) < 64))
{
if (page)
mprotect(page, pagesize, PROT_READ | PROT_EXEC);
page = mmap(NULL, pagesize * 2, PROT_READ | PROT_WRITE | PROT_EXEC, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
const size_t diff = (((size_t)page) % 0x10000);
if (diff) { // align to 64k, unmap the difference.
void *origpage = page;
page = ((uint8 *) page) + (0x10000 - diff);
munmap(origpage, 0x10000 - diff);
} else {
munmap(((uint8 *)page) + 0x10000, 0x10000); // unmap the extra half we didn't need.
} // else
pageused = 0;
uint16 offset = 0xFFFF;
selector = 0xFFFF;
findSelector((uint32) page, &selector, &offset, 1);
assert(selector != 0xFFFF);
assert(offset == 0);
} // if
void *trampoline = page + pageused;
char *ptr = (char *) trampoline;
char *module = strdup(_module);
char *entry = strdup(_entry);
// convert stack to linear address...
*(ptr++) = 0x8C; /* mov ax,ss... */
*(ptr++) = 0xD0; /* ...mov ax,ss */
*(ptr++) = 0xC1; /* shr ax,byte 0x3... */
*(ptr++) = 0xE8; /* ...shr ax,byte 0x3 */
*(ptr++) = 0x03; /* ...shr ax,byte 0x3 */
*(ptr++) = 0x66; /* shl eax,byte 0x10... */
*(ptr++) = 0xC1; /* ...shl eax,byte 0x10 */
*(ptr++) = 0xE0; /* ...shl eax,byte 0x10 */
*(ptr++) = 0x10; /* ...shl eax,byte 0x10 */
*(ptr++) = 0x89; /* mov ax,sp... */
*(ptr++) = 0xE0; /* ...mov ax,sp */
// jmp to 32-bit code...
*(ptr++) = 0x66; /* jmp dword 0x7788:0x33332222... */
*(ptr++) = 0xEA; /* ...jmp dword 0x7788:0x33332222 */
const uint32 jmp32addr = (uint32) (ptr + 6);
memcpy(ptr, &jmp32addr, 4); ptr += 4;
memcpy(ptr, &GLoaderState->original_cs, 2); ptr += 2;
// now we're in 32-bit land again.
*(ptr++) = 0x66; /* mov cx,0xabcd... */
*(ptr++) = 0xB9; /* ...mov cx,0xabcd */
memcpy(ptr, &GLoaderState->original_ss, 2); ptr += 2;
*(ptr++) = 0x8E; /* mov ss,ecx... */
*(ptr++) = 0xD1; /* ...mov ss,ecx */
*(ptr++) = 0x89; /* mov esp,eax... */
*(ptr++) = 0xC4; /* ...mov esp,eax */
*(ptr++) = 0x66; /* mov cx,0x8888... */
*(ptr++) = 0xB9; /* ...mov cx,0x8888 */
memcpy(ptr, &GLoaderState->original_ds, 2); ptr += 2;
*(ptr++) = 0x66; /* mov cx,0x8888... */
*(ptr++) = 0xB9; /* ...mov cx,0x8888 */
memcpy(ptr, &GLoaderState->original_es, 2); ptr += 2;
*(ptr++) = 0x8E; /* mov es,ecx... */ \
*(ptr++) = 0xC1; /* ...mov es,ecx */ \
// okay, CPU is in a sane state again, call the trampoline. Don't bother cleaning up.
*(ptr++) = 0x68; // pushl immediate
memcpy(ptr, &entry, sizeof (char *));
ptr += sizeof (uint32);
*(ptr++) = 0x68; // pushl immediate
memcpy(ptr, &module, sizeof (char *));
ptr += sizeof (uint32);
*(ptr++) = 0xB8; // movl immediate to %eax
const void *fn = missingEntryPointCalled;
memcpy(ptr, &fn, sizeof (void *));
ptr += sizeof (void *);
*(ptr++) = 0xFF; // call absolute in %eax.
*(ptr++) = 0xD0; // ...call absolute in %eax.
// (and never return.)
const uint32 trampoline_len = (uint32) (ptr - ((char *) trampoline));
assert(trampoline_len <= 64);
pageused += trampoline_len;
if (pageused % 4) // keep these aligned to 32 bits.
pageused += (4 - (pageused % 4));
//printf("Generated trampoline %p for module '%s' 16-bit export '%s'\n", trampoline, module, entry);
// this hack is not thread safe and only works at all because we don't store this long-term.
static LxExport lxexp;
static LxMmaps lxmmap;
lxexp.addr = trampoline;
lxexp.object = &lxmmap;
lxmmap.mapped = lxmmap.addr = page;
lxmmap.size = 0x10000;
lxmmap.alias = selector;
*_lxexp = &lxexp;
return trampoline;
} // generateMissingTrampoline16
static __attribute__((noreturn)) void runLxModule(LxModule *lxmod, const int argc, char **argv, char **envp)
{
uint8 *stack = (uint8 *) ((size_t) lxmod->esp);
// ...and you pass it the pointer to argv0. This is (at least as far as the docs suggest) appended to the environment table.
//fprintf(stderr, "jumping into LX land for exe '%s'...! eip=%p esp=%p\n", lxmod->name, (void *) lxmod->eip, stack); fflush(stderr);
GLoaderState->running = 1;
__asm__ __volatile__ (
"movl %%esi,%%esp \n\t" // use the OS/2 process's stack.
"pushl %%eax \n\t" // cmd
"pushl %%ecx \n\t" // env
"pushl $0 \n\t" // reserved
"pushl %%edx \n\t" // module handle
"leal 1f,%%eax \n\t" // address that entry point should return to.
"pushl %%eax \n\t"
"pushl %%edi \n\t" // the OS/2 process entry point (we'll "ret" to it instead of jmp, so stack and registers are all correct).
"xorl %%eax,%%eax \n\t"
"xorl %%ebx,%%ebx \n\t"
"xorl %%ecx,%%ecx \n\t"
"xorl %%edx,%%edx \n\t"
"xorl %%esi,%%esi \n\t"
"xorl %%edi,%%edi \n\t"
"xorl %%ebp,%%ebp \n\t"
"ret \n\t" // go to OS/2 land!
"1: \n\t" // ...and return here.
"pushl %%eax \n\t" // push exit code from OS/2 app.
"call endLxProcess \n\t" // never returns.
// If we returned here, %eax has the exit code from the app.
: // no outputs.
: "a" (GLoaderState->pib.pib_pchcmd),
"c" (GLoaderState->pib.pib_pchenv),
"d" (lxmod), "S" (stack), "D" (lxmod->eip)
: "memory"
);
(void) endLxProcess; // make compiler happy.
__builtin_unreachable();
} // runLxModule
static void runLxLibraryInitOrTerm(LxModule *lxmod, const int isTermination)
{
uint8 *stack = NULL;
// force us over to OS/2 main module's stack if we aren't already on it.
if (!GLoaderState->running)
stack = (uint8 *) ((size_t) GLoaderState->main_module->esp);
//fprintf(stderr, "jumping into LX land to %s library '%s'...! eip=%p esp=%p\n", isTermination ? "terminate" : "initialize", lxmod->name, (void *) lxmod->eip, stack); fflush(stderr);
__asm__ __volatile__ (
"pushal \n\t" // save all the current registers.
"pushfl \n\t" // save all the current flags.
"movl %%esp,%%ecx \n\t" // save our stack to a temporary register.
"testl %%esi,%%esi \n\t" // force the OS/2 process's stack?
"je 1f \n\t" // if 0, nope, we're already good.
"movl %%esi,%%esp \n\t" // use the OS/2 process's stack.
"1: \n\t" //
"pushl %%ecx \n\t" // save original stack pointer for real.
"pushl %%eax \n\t" // isTermination
"pushl %%edx \n\t" // library module handle
"leal 2f,%%eax \n\t" // address that entry point should return to.
"pushl %%eax \n\t"
"pushl %%edi \n\t" // the OS/2 library entry point (we'll "ret" to it instead of jmp, so stack and registers are all correct).
"xorl %%eax,%%eax \n\t"
"xorl %%ebx,%%ebx \n\t"
"xorl %%ecx,%%ecx \n\t"
"xorl %%edx,%%edx \n\t"
"xorl %%esi,%%esi \n\t"
"xorl %%edi,%%edi \n\t"
"xorl %%ebp,%%ebp \n\t"
"ret \n\t" // go to OS/2 land!
"2: \n\t" // ...and return here.
"addl $8,%%esp \n\t" // drop arguments to entry point.
"popl %%esp \n\t" // restore native process stack now.
"popfl \n\t" // restore our original flags.
"popal \n\t" // restore our original registers.
: // no outputs
: "a" (isTermination), "d" (lxmod), "S" (stack), "D" (lxmod->eip)
: "memory"
);
//fprintf(stderr, "...survived time in LX land!\n"); fflush(stderr);
// !!! FIXME: this entry point returns a result...do we abort if it reports error?
// !!! FIXME: (actually, DosLoadModule() can report that failure. Abort if (GLoaderState->running == 0), though!)
} // runLxLibraryInitOrTerm
static void runLxLibraryInit(LxModule *lxmod)
{
// we don't check the LIBINIT flag, because if the EIP fields are valid
// but this bit is missing, we're supposed to do "global" initialization,
// which I guess means it runs once for all processes on the system
// instead of once per process...but we aren't really a full OS/2 system
// so maybe it's okay to do global init in isolation...? We'll cross that
// bridge when we come to it, I guess. Either way: this is running here,
// flag or not.
if (1) { //if (lxmod->module_flags & 0x4) { // LIBINIT flag
if (lxmod->lx.eip_object != 0)
runLxLibraryInitOrTerm(lxmod, 0);
} // if
} // runLxLibraryInit
static void runLxLibraryTerm(LxModule *lxmod)
{
// See notes about global initialization in runLxLibraryInit(); it
// applies to deinit here, too.
if (1) { //if (lxmod->module_flags & 0x40000000) { // LIBTERM flag
if (lxmod->lx.eip_object != 0)
runLxLibraryInitOrTerm(lxmod, 1);
} // if
} // runLxLibraryTerm
static void freeLxModule(LxModule *lxmod)
{
if (!lxmod)
return;
//printf("freeing %s module '%s' (starting refcount=%d) ...\n", lxmod->nativelib ? "native" : "LX", lxmod->name, (int) lxmod->refcount); fflush(stdout);
// !!! FIXME: mutex from here
lxmod->refcount--;
//fprintf(stderr, "unref'd module '%s' to %u\n", lxmod->name, (uint) lxmod->refcount);
if (lxmod->refcount > 0)
return; // something is still using it.
if ((lxmod->initialized) && (lxmod != GLoaderState->main_module)) {
if (!lxmod->nativelib) {
runLxLibraryTerm(lxmod);
} else {
LxNativeModuleDeinitEntryPoint fn = (LxNativeModuleDeinitEntryPoint) dlsym(lxmod->nativelib, "lxNativeModuleDeinit");
if (fn)
fn();
} // else
} // if
if (lxmod->next)
lxmod->next->prev = lxmod->prev;
if (lxmod->prev)
lxmod->prev->next = lxmod->next;
if (lxmod == GLoaderState->loaded_modules)
GLoaderState->loaded_modules = lxmod->next;
if (GLoaderState->main_module == lxmod) {
GLoaderState->main_module = NULL;
LxMmaps *lxmmap = &lxmod->mmaps[lxmod->lx.esp_object - 1];
const uint32 stackbase = (uint32) ((size_t)lxmmap->addr);
initOs2StackSegments(stackbase, lxmmap->size, 1);
lxmmap->mapped = NULL; // don't unmap the stack we're probably using!
} // if
// !!! FIXME: mutex to here
for (uint32 i = lxmod->lx.num_import_mod_entries; i > 0; i--)
freeLxModule(lxmod->dependencies[i-1]);
free(lxmod->dependencies);
for (uint32 i = 0; i < lxmod->lx.module_num_objects; i++) {
if (lxmod->mmaps[i].alias != 0xFFFF)
freeSelector(lxmod->mmaps[i].alias);
if (lxmod->mmaps[i].mapped)
munmap(lxmod->mmaps[i].mapped, lxmod->mmaps[i].size);
} // for
free(lxmod->mmaps);
if (lxmod->nativelib)
dlclose(lxmod->nativelib);
else {
for (uint32 i = 0; i < lxmod->num_exports; i++)
free((void *) lxmod->exports[i].name);
free((void *) lxmod->exports);
} // else
//printf("Freed module '%s'\n", lxmod->name); fflush(stdout);
free(lxmod);
} // freeLxModule
static LxModule *loadLxModuleByModuleNameInternal(const char *modname, const int dependency_tree_depth);
static void *getModuleProcAddrByOrdinal(const LxModule *module, const uint32 ordinal, const LxExport **_lxexp, const int want16bit)
{
//printf("lookup module == '%s', ordinal == %u\n", module->name, (uint) ordinal);
const LxExport *lxexp = module->exports;
for (uint32 i = 0; i < module->num_exports; i++, lxexp++) {
if (lxexp->ordinal == ordinal) {
if (_lxexp)
*_lxexp = lxexp;
void *retval = lxexp->addr;
if (lxexp->object && lxexp->object->alias != 0xFFFF) // 16-bit bridge? this is actually a void**, due to some macro salsa. :/
retval = *((void**) retval);
return retval;
} // if
} // for
if (_lxexp)
*_lxexp = NULL;
#if 1
char entry[128];
snprintf(entry, sizeof (entry), "ordinal #%u", (uint) ordinal);
return want16bit ? generateMissingTrampoline16(module->name, entry, _lxexp) : generateMissingTrampoline(module->name, entry);
#else
return NULL;
#endif
} // getModuleProcAddrByOrdinal
static void *getModuleProcAddrByName(const LxModule *module, const char *name, const LxExport **_lxexp, const int want16bit)
{
//printf("lookup module == '%s', name == '%s'\n", module->name, name);
const LxExport *lxexp = module->exports;
for (uint32 i = 0; i < module->num_exports; i++, lxexp++) {
if (strcmp(lxexp->name, name) == 0) {
if (_lxexp)
*_lxexp = lxexp;
void *retval = lxexp->addr;
if (lxexp->object && lxexp->object->alias != 0xFFFF) // 16-bit bridge? this is actually a void**, due to some macro salsa. :/
retval = *((void**) retval);
return retval;
} // if
} // for
if (_lxexp)
*_lxexp = NULL;
#if 1
return want16bit ? generateMissingTrampoline16(module->name, name, _lxexp) : generateMissingTrampoline(module->name, name);
#else
return NULL;
#endif
} // getModuleProcAddrByName
static void doFixup(uint8 *page, const sint16 offset, const uint32 finalval, const uint16 finalval2, const uint32 finalsize)
{
#if 0
if (finalsize == 6) {
printf("fixing up %p to 0x%X:0x%X (6 bytes)...\n", page + offset, (uint) finalval2, (uint) finalval);
} else {
printf("fixing up %p to 0x%X (%u bytes)...\n", page + offset, (uint) finalval, (uint) finalsize);
} // else
fflush(stdout);
#endif
switch (finalsize) {
case 1: { uint8 *dst = (uint8 *) (page + offset); *dst = (uint8) finalval; } break;
case 2: { uint16 *dst = (uint16 *) (page + offset); *dst = (uint16) finalval; } break;
case 4: { uint32 *dst = (uint32 *) (page + offset); *dst = (uint32) finalval; } break;
case 6: {
uint32 *dst1 = (uint32 *) (page + offset);
*dst1 = (uint32) finalval;
uint16 *dst2 = (uint16 *) (page + offset + 4);
*dst2 = (uint16) finalval2;
break;
} // case
default:
fprintf(stderr, "BUG! Unexpected fixup final size of %u\n", (uint) finalsize);
exit(1);
} // switch
} // doFixup
static void fixupPage(const uint8 *exe, LxModule *lxmod, const LxObjectTableEntry *obj, const uint32 pagenum, uint8 *page)
{
const LxHeader *lx = &lxmod->lx;
//const LxObjectTableEntry *origobj = ((const LxObjectTableEntry *) (exe + lx->object_table_offset));
const uint32 *fixuppage = (((const uint32 *) (exe + lx->fixup_page_table_offset)) + ((obj->page_table_index - 1) + pagenum));
const uint32 fixupoffset = *fixuppage;
const uint32 fixuplen = fixuppage[1] - fixuppage[0];
const uint8 *fixup = (exe + lx->fixup_record_table_offset) + fixupoffset;
const uint8 *fixupend = fixup + fixuplen;
//int record = 0;
while (fixup < fixupend) {
//record++; printf("FIXUP obj #%u page #%u record #: %d\n", (uint) (obj - origobj), (uint) pagenum, record);
const uint8 srctype = *(fixup++);
const uint8 fixupflags = *(fixup++);
uint8 srclist_count = 0;
sint16 srcoffset = 0;
uint32 finalval = 0;
uint16 finalval2 = 0;
uint32 finalsize = 0;
int allow_fixup_to_alias = 0;
switch (srctype & 0xF) {
case 0x0: // byte fixup
finalsize = 1;
break;
case 0x2: // 16-bit selector fixup
finalsize = 2;
allow_fixup_to_alias = 1;
break;
case 0x5: // 16-bit offset fixup
finalsize = 2;
break;
case 0x3: // 16:16 pointer fixup
finalsize = 4;
allow_fixup_to_alias = 1;
break;
case 0x7: // 32-bit offset fixup
case 0x8: // 32-bit self-relative offset fixup
finalsize = 4;
break;
case 0x6: // 16:32 pointer fixup
finalval2 = GLoaderState->original_cs;
finalsize = 6;
allow_fixup_to_alias = 1;
break;
} // switch
const int fixup_to_alias = ((srctype & 0x10) != 0);
if (fixup_to_alias) { // fixup to alias flag.
if (!allow_fixup_to_alias)
fprintf(stderr, "WARNING: Bogus fixup srctype (%u) with fixup-to-alias flag!\n", (uint) (srctype & 0xF));
} // if
if (srctype & 0x20) { // contains a source list
srclist_count = *(fixup++);
} else {
srcoffset = *((sint16 *) fixup);
fixup += 2;
} // else
switch (fixupflags & 0x3) {
case 0x0: { // Internal fixup record
uint16 objectid = 0;
if (fixupflags & 0x40) { // 16 bit value
objectid = *((uint16 *) fixup); fixup += 2;
} else {
objectid = (uint16) *(fixup++);
} // else
uint32 targetoffset = 0;
if ((srctype & 0xF) != 2) { // not used for 16-bit selector fixups.
if (fixupflags & 0x10) { // 32-bit target offset
targetoffset = *((uint32 *) fixup); fixup += 4;
} else { // 16-bit target offset
targetoffset = (uint32) (*((uint16 *) fixup)); fixup += 2;
} // else
} // if
if (!fixup_to_alias) {
const uint32 base = (uint32) (size_t) lxmod->mmaps[objectid - 1].addr;
finalval = base + targetoffset;
} else {
if (lxmod->mmaps[objectid - 1].alias == 0xFFFF) {
fprintf(stderr, "uhoh, need a 16-bit alias fixup, but object has no 16:16 alias!\n");
} else {
const uint16 selector = (lxmod->mmaps[objectid - 1].alias << 3) | 7;
switch (srctype & 0xF) {
case 0x2: finalval = selector; break; // 16-bit selector fixup?
case 0x3: finalval = (((uint32) selector) << 16) | targetoffset; break; // 16:16 pointer fixup
case 0x6: finalval = targetoffset; finalval2 = selector; break; // 16:32 pointer fixup
default: assert(!"shouldn't hit this code"); break;
} // switch
} // else
} // else
break;
} // case
case 0x1: { // Import by ordinal fixup record
uint16 moduleid = 0; // module ordinal
if (fixupflags & 0x40) { // 16 bit value
moduleid = *((uint16 *) fixup); fixup += 2;
} else {
moduleid = (uint16) *(fixup++);
} // else
uint32 importid = 0; // import ordinal
if (fixupflags & 0x80) { // 8 bit value
importid = (uint32) *(fixup++);
} else if (fixupflags & 0x10) { // 32-bit value
importid = *((uint32 *) fixup); fixup += 4;
} else { // 16-bit value
importid = (uint32) *((uint16 *) fixup); fixup += 2;
} // else
const LxExport *lxexp = NULL;
if (moduleid == 0) {
fprintf(stderr, "uhoh, looking for module ordinal 0, which is illegal.\n");
} else if (moduleid > lx->num_import_mod_entries) {
fprintf(stderr, "uhoh, looking for module ordinal %u, but only %u available.\n", (uint) moduleid, (uint) lx->num_import_mod_entries);
} else {
//printf("import-by-ordinal fixup: module=%u import=%u\n", (uint) moduleid, (uint) importid);
finalval = (uint32) (size_t) getModuleProcAddrByOrdinal(lxmod->dependencies[moduleid-1], importid, &lxexp, fixup_to_alias);
} // else
if (fixup_to_alias) {
if (!lxexp || !lxexp->object || (lxexp->object->alias == 0xFFFF)) {
fprintf(stderr, "uhoh, couldn't find a selector for a fixup-to-alias address!\n");
} else {
const uint16 selector = (lxexp->object->alias << 3) | 7;
switch (srctype & 0xF) {
case 0x2: finalval = selector; break; // 16-bit selector fixup? !!! FIXME:
case 0x3: finalval = (((uint32) selector) << 16) | (finalval - ((uint32)lxexp->object->addr)); break; // 16:16 pointer fixup
case 0x6: finalval -= ((uint32)lxexp->object->addr); finalval2 = selector; break; // 16:32 pointer fixup
default: assert(!"shouldn't hit this code"); break;
} // switch
} // else
} // else
break;
} // case
case 0x2: { // Import by name fixup record
uint16 moduleid = 0; // module ordinal
if (fixupflags & 0x40) { // 16 bit value
moduleid = *((uint16 *) fixup); fixup += 2;
} else {
moduleid = (uint16) *(fixup++);
} // else
uint32 name_offset = 0;
if (fixupflags & 0x10) { // 32-bit value
name_offset = *((uint32 *) fixup); fixup += 4;
} else { // 16-bit value
name_offset = *((uint16 *) fixup); fixup += 2;
} // else
const LxExport *lxexp = NULL;
if (moduleid == 0) {
fprintf(stderr, "uhoh, looking for module ordinal 0, which is illegal.\n");
} else if (moduleid > lx->num_import_mod_entries) {
fprintf(stderr, "uhoh, looking for module ordinal %u, but only %u available.\n", (uint) moduleid, (uint) lx->num_import_mod_entries);
} else {
const uint8 *import_name = (exe + lx->import_proc_table_offset) + name_offset;
char name[128];
const uint8 namelen = *(import_name++) & 0x7F; // the top bit is reserved.
memcpy(name, import_name, namelen);
name[namelen] = '\0';
//printf("import-by-name fixup: module=%u import='%s'\n", (uint) moduleid, name);
finalval = (uint32) (size_t) getModuleProcAddrByName(lxmod->dependencies[moduleid-1], name, &lxexp, fixup_to_alias);
} // else
if (fixup_to_alias) {
if (!lxexp || !lxexp->object || (lxexp->object->alias == 0xFFFF)) {
fprintf(stderr, "uhoh, couldn't find a selector for a fixup-to-alias address!\n");
} else {
const uint16 selector = (lxexp->object->alias << 3) | 7;
switch (srctype & 0xF) {
case 0x2: finalval = selector; break; // 16-bit selector fixup? !!! FIXME:
case 0x3: finalval = (((uint32) selector) << 16) | (finalval - ((uint32)lxexp->object->addr)); break; // 16:16 pointer fixup
case 0x6: finalval -= ((uint32)lxexp->object->addr); finalval2 = selector; break; // 16:32 pointer fixup
default: assert(!"shouldn't hit this code"); break;
} // switch
} // else
} // else
break;
} // case
case 0x3: { // Internal entry table fixup record
FIXME("FIXUP 0x3 WRITE ME");
assert(!"write me");
_exit(1);
break;
} // case
} // switch
if (fixupflags & 0x4) { // Has additive.
uint32 additive = 0;
if (fixupflags & 0x20) { // 32-bit value
additive = *((uint32 *) fixup); fixup += 4;
} else { // 16-bit value
additive = (uint32) *((uint16 *) fixup);
fixup += 2;
} // else
finalval += additive;
} // if
if (srctype & 0x20) { // source list
for (uint8 i = 0; i < srclist_count; i++) {
const sint16 offset = *((sint16 *) fixup); fixup += 2;
if ((srctype & 0xF) == 0x08) { // self-relative fixup?
assert(finalval2 == 0);
doFixup(page, offset, finalval - (((uint32)page)+offset+4), 0, finalsize);
} else {
doFixup(page, offset, finalval, finalval2, finalsize);
} // else
} // for
} else {
if ((srctype & 0xF) == 0x08) { // self-relative fixup?
assert(finalval2 == 0);
doFixup(page, srcoffset, finalval - (((uint32)page)+srcoffset+4), 0, finalsize);
} else {
doFixup(page, srcoffset, finalval, finalval2, finalsize);
} // else
} // else
} // while
} // fixupPage
static int loadLxNameTable(LxModule *lxmod, const uint8 *name_table)
{
for (uint32 i = 0; *name_table; i++) {
const uint8 namelen = *(name_table++);
const uint8 *nameptr = name_table;
name_table += namelen;
const uint16 ordinal = *((const uint16 *) name_table); name_table += 2;
if (ordinal == 0)
continue; // skip this one.
LxExport *export = (LxExport *) lxmod->exports;
const uint32 num_exports = lxmod->num_exports;
for (uint32 i = 0; i < num_exports; i++, export++) {
if (export->ordinal == ordinal) {
char *name = (char *) malloc(namelen + 1);
if (!name) {
fprintf(stderr, "Out of memory!\n");
return 0;
} // if
memcpy(name, nameptr, namelen);
name[namelen] = '\0';
export->name = name;
break;
} // if
} // for
} // for
return 1;
} // loadLxNameTable
// This is how I understand this mess, which I could be wrong about.
// Apparently 32-bit ring-3 code on OS/2 uses code segment 0x5B, even though
// generally 32-bit apps don't think about their _segment_ because they have
// a linear address space. This is true on Linux, too, and the kernel
// hardcodes a segment for user-space code (0x23 at the moment, at least for
// x86-32 code running on an x86-64 kernel. It's a different hardcoded number
// on x86-32 kernels, too).
// Code (from IBM!) exists in the wild that hardcodes references to the OS/2
// code segment, which means if the linear address space isn't on that
// segment, programs will crash if they explicitly reference it.
// This is hard to map around on Linux because we can't meaningfully mess with
// the GDT in a flexible way.
// In theory, the only place we should ever see a hardcoded reference to
// CS 0x5B is in a 16-bit thunk that is trying to jump back to 32-bit mode.
// 16-bit code wouldn't otherwise reference it, being 16-bit, and 32-bit
// code wouldn't need to explicitly reference it.
// Even still, most tools (EMX, etc) don't do this. I couldn't find any
// mention that OS/2 guarantees this code segment will exist, just that it
// seems to map 32-bit apps there and it's probably normal since Linux uses
// roughly the same approach. If it had ever changed, it would definitely
// break some programs.
// So we go through object pages that are marked as 16:16 and EXEC, and look
// for things that look like absolute jmps to code segment 0x5B, and patch
// them up to the host's actual linear address code segment. This is nasty,
// but oh well.
static void fixupLinearCodeSegmentReferences(uint8 *addr, size_t size)
{
// in lieu of writing a full x86 instruction decoder, we just look for
// 0xEA (JMP LARGE FAR PTR ADDR), skip 4 bytes (the 32-bit offset), and
// see if the next two bytes are 0x5B 0x00 (the 16-bit segment). This is
// wrong but "good enough" for now.
while (size >= 7) {
size--;
if (*(addr++) == 0xEA) {
if ((addr[4] == 0x5B) && (addr[5] == 0x00)) {
//printf("Patching out code segment 0x5B at %p\n", addr+4);
memcpy(&addr[4], &GLoaderState->original_cs, 2);
size -= 6;
addr += 6;
} // if
} // if
} // while
} // fixupLinearCodeSegmentReferences
// !!! FIXME: break up this function.
static LxModule *loadLxModule(const char *fname, uint8 *exe, uint32 exelen, int dependency_tree_depth)
{
//printf("loadLxModule('%s')\n", fname); fflush(stdout);
LxModule *retval = NULL;
const uint8 *origexe = exe;
//const uint32 origexelen = exelen;
if (!sanityCheckLxModule(&exe, &exelen))
goto loadlx_failed;
const LxHeader *lx = (const LxHeader *) exe;
const uint32 module_type = lx->module_flags & 0x00038000;
if ((module_type != 0x0000) && (module_type != 0x8000)) {
fprintf(stderr, "This is not a standard .exe or .dll (maybe device driver?)\n");
goto loadlx_failed;
} // if
const int isDLL = (module_type == 0x8000);
if (isDLL && !GLoaderState->main_module) {
fprintf(stderr, "uhoh, need to load an .exe before a .dll!\n");
goto loadlx_failed;
} else if (!isDLL && GLoaderState->main_module) {
fprintf(stderr, "uhoh, loading an .exe after already loading one!\n");
goto loadlx_failed;
} // if else if
retval = (LxModule *) malloc(sizeof (LxModule));
if (!retval) {
fprintf(stderr, "Out of memory!\n");
goto loadlx_failed;
} // if
memset(retval, '\0', sizeof (*retval));
retval->refcount = 1;
retval->dependencies = (LxModule **) malloc(sizeof (LxModule *) * lx->num_import_mod_entries);
retval->mmaps = (LxMmaps *) malloc(sizeof (LxMmaps) * lx->module_num_objects);
if (!retval->dependencies || !retval->mmaps) {
fprintf(stderr, "Out of memory!\n");
goto loadlx_failed;
} // if
memset(retval->dependencies, '\0', sizeof (LxModule *) * lx->num_import_mod_entries);
memset(retval->mmaps, '\0', sizeof (LxMmaps) * lx->module_num_objects);
for (int i = 0; i < lx->module_num_objects; i++)
retval->mmaps[i].alias = 0xFFFF;
memcpy(&retval->lx, lx, sizeof (*lx));
if (lx->resident_name_table_offset) {
const uint8 *name_table = exe + lx->resident_name_table_offset;
const uint8 namelen = *(name_table++);
char *ptr = retval->name;
for (uint32 i = 0; i < namelen; i++) {
const char ch = *(name_table++);
*(ptr++) = ((ch >= 'a') && (ch <= 'z')) ? (ch + ('A' - 'a')) : ch;
} // for
*ptr = '\0';
} // if
if (!isDLL) {
GLoaderState->main_module = retval;
GLoaderState->pib.pib_hmte = retval;
} // else if
const char *modname = retval->name;
//printf("ref'd new module '%s' to %u\n", modname, 1);
// !!! FIXME: apparently OS/2 does 1024, but they're not loading the module into RAM each time.
// !!! FIXME: the spec mentions the 1024 thing for "forwarder" records in the entry table,
// !!! FIXME: specifically. _Can_ two DLLs depend on each other? We'll have to load both and
// !!! FIXME: then fix them up without recursing.
if (++dependency_tree_depth > 32) {
fprintf(stderr, "Likely circular dependency in module '%s'\n", modname);
goto loadlx_failed;
} // if
int uses_aliases = 0;
const LxObjectTableEntry *obj = ((const LxObjectTableEntry *) (exe + lx->object_table_offset));
for (uint32 i = 0; i < lx->module_num_objects; i++, obj++) {
if (obj->object_flags & 0x8) // !!! FIXME: resource object; ignore this until resource support is written, later.
continue;
uint32 vsize = obj->virtual_size;
if ((vsize % lx->page_size) != 0)
vsize += lx->page_size - (vsize % lx->page_size);
const int needs_1616_alias = ((obj->object_flags & 0x1000) != 0); // Object needs a 16:16 alias.
if (needs_1616_alias) {
if (vsize > 0x10000) {
fprintf(stderr, "Module '%s' object #%u needs a 16:16 alias, but is > 64k\n", modname, (uint) (i+1));
goto loadlx_failed; // I guess this is an error...?
} // if
uses_aliases = 1;
if (isDLL) // (specifically: if !MAP_FIXED)
vsize += 0x10000; // make sure we can align to a 64k boundary.
} // if
const int mmapflags = MAP_ANONYMOUS | MAP_PRIVATE | (isDLL ? 0 : MAP_FIXED);
void *base = isDLL ? NULL : (void *) ((size_t) obj->reloc_base_addr);
void *mmapaddr = mmap(base, vsize, PROT_READ|PROT_WRITE, mmapflags, -1, 0);
// we'll mprotect() these pages to the proper permissions later.
//fprintf(stderr, "%s lxobj #%u mmap(%p, %u, %c%c%c, ANON|PRIVATE%s, -1, 0) == %p\n", retval->name, (uint) i, base, (uint) vsize, (obj->object_flags & 0x1) ? 'R' : '-', (obj->object_flags & 0x2) ? 'W' : '-', (obj->object_flags & 0x4) ? 'X' : '-', isDLL ? "" : "|FIXED", mmapaddr);
if (mmapaddr == ((void *) MAP_FAILED)) {
fprintf(stderr, "mmap(%p, %u, RW-, ANON|PRIVATE%s, -1, 0) failed (%d): %s\n",
base, (uint) vsize, isDLL ? "" : "|FIXED", errno, strerror(errno));
goto loadlx_failed;
} // if
retval->mmaps[i].mapped = mmapaddr;
retval->mmaps[i].size = vsize;
// force objects with a 16:16 alias to a 64k boundary.
size_t adjust = (size_t) mmapaddr;
if (needs_1616_alias && ((adjust % 0x10000) != 0)) {
assert(isDLL); // this must be fixed to a specific address, hopefully handled this...?
const size_t diff = 0x10000 - (adjust % 0x10000);
vsize -= diff;
adjust += diff;
mmapaddr = (void *) adjust;
} // if
retval->mmaps[i].addr = mmapaddr;
const LxObjectPageTableEntry *objpage = ((const LxObjectPageTableEntry *) (exe + lx->object_page_table_offset));
objpage += obj->page_table_index - 1;
uint8 *dst = (uint8 *) mmapaddr;
const uint32 numPageTableEntries = obj->num_page_table_entries;
for (uint32 pagenum = 0; pagenum < numPageTableEntries; pagenum++, objpage++) {
const uint8 *src;
switch (objpage->flags) {
case 0x00: // preload
src = origexe + lx->data_pages_offset + (objpage->page_data_offset << lx->page_offset_shift);
memcpy(dst, src, objpage->data_size);
if (objpage->data_size < lx->page_size) {
memset(dst + objpage->data_size, '\0', lx->page_size - objpage->data_size);
}
break;
case 0x01: // iterated data.
// LX format docs say object_iter_pages_offset must be zero or equal to data_pages_offset for OS/2 2.0. So just use data_pages_offset here.
//src = origexe + lx->object_iter_pages_offset + (objpage->page_data_offset << lx->page_offset_shift);
src = origexe + lx->data_pages_offset + (objpage->page_data_offset << lx->page_offset_shift);
if (!decompressIterated(dst, lx->page_size, src, objpage->data_size)) {
fprintf(stderr, "Failed to decompress iterated object page (corrupt file or bug).\n");
goto loadlx_failed;
} // if
break;
case 0x02: // INVALID, just zero it out.
case 0x03: // ZEROFILL, just zero it out.
memset(dst, '\0', lx->page_size);
break;
case 0x05: // exepack2
src = origexe + lx->data_pages_offset + (objpage->page_data_offset << lx->page_offset_shift);
if (!decompressExePack2(dst, lx->page_size, src, objpage->data_size)) {
fprintf(stderr, "Failed to decompress object page (corrupt file or bug).\n");
goto loadlx_failed;
} // if
break;
case 0x08: // !!! FIXME: this is listed in lxlite, presumably this is exepack3 or something. Maybe this was new to Warp4, like exepack2 was new to Warp3. Pull this algorithm in from lxlite later.
default:
fprintf(stderr, "Don't know how to load an object page of type %u!\n", (uint) objpage->flags);
goto loadlx_failed;
} // switch
dst += lx->page_size;
} // for
// any bytes at the end of this object that we didn't initialize? Zero them out.
const uint32 remain = vsize - ((uint32) (dst - ((uint8 *) mmapaddr)));
if (remain)
memset(dst, '\0', remain);
} // for
// All the pages we need from the EXE are loaded into the appropriate spots in memory.
//printf("mmap()'d everything we need!\n");
retval->eip = lx->eip;
if (lx->eip_object != 0) {
const uint32 base = (uint32) ((size_t)retval->mmaps[lx->eip_object - 1].addr);
retval->eip += base;
} // if
// !!! FIXME: esp==0 means something special for programs (and is ignored for library init).
// !!! FIXME: "A zero value in this field indicates that the stack pointer is to be initialized to the highest address/offset in the object"
if (!isDLL) {
assert(lx->esp_object != 0);
const LxMmaps *lxmmap = &retval->mmaps[lx->esp_object - 1];
const uint32 stackbase = (uint32) ((size_t)lxmmap->addr);
const uint32 stacksize = (uint32) lxmmap->size;
retval->esp = lx->esp + stackbase;
// This needs to be set up now, so it's available to any library
// init code that runs in LX land.
initOs2Tib(GLoaderState->main_tibspace, (void *) ((size_t) retval->esp), stacksize, 0);
initOs2StackSegments(stackbase, stacksize, 0);
} // if
// now we have the stack tiled--and it got the specific selectors it
// needed--let's start making 16:16 aliases for the appropriate objects.
if (uses_aliases) {
obj = ((const LxObjectTableEntry *) (exe + lx->object_table_offset));
for (uint32 i = 0; i < lx->module_num_objects; i++, obj++) {
if ((obj->object_flags & 0x1000) == 0)
continue; // Object doesn't need a 16:16 alias, skip it.
uint16 offset = 0;
const int iscode = (obj->object_flags & 0x4) ? 1 : 0;
if (!findSelector((uint32) (size_t) retval->mmaps[i].addr, &retval->mmaps[i].alias, &offset, iscode)) {
fprintf(stderr, "Ran out of LDT entries getting a 16:16 alias for '%s' object #%u!\n", modname, (uint) (i + 1));
goto loadlx_failed;
} // if
assert(offset == 0);
if (obj->object_flags & 0x4) { // 16:16 segment with code.
fixupLinearCodeSegmentReferences((uint8 *) (size_t) retval->mmaps[i].mapped, retval->mmaps[i].size);
}
} // for
} // if
// Set up our exports...
uint32 total_ordinals = 0;
const uint8 *entryptr = exe + lx->entry_table_offset;
while (*entryptr) { /* end field has a value of zero. */
const uint8 numentries = *(entryptr++); /* number of entries in this bundle */
const uint8 bundletype = *(entryptr++) & ~0x80;
if (bundletype != 0x00) {
total_ordinals += numentries;
entryptr += 2 + ((bundletype == 0x01) ? 3 : 5) * numentries;
} // if
} // while
LxExport *lxexp = (LxExport *) malloc(sizeof (LxExport) * total_ordinals);
if (!lxexp) {
fprintf(stderr, "Out of memory!\n");
goto loadlx_failed;
} // if
memset(lxexp, '\0', sizeof (LxExport) * total_ordinals);
retval->exports = lxexp;
uint32 ordinal = 1;
entryptr = exe + lx->entry_table_offset;
while (*entryptr) { /* end field has a value of zero. */
const uint8 numentries = *(entryptr++); /* number of entries in this bundle */
const uint8 bundletype = *(entryptr++) & ~0x80;
uint16 objidx = 0;
switch (bundletype) {
case 0x00: // UNUSED
ordinal += numentries;
break;
case 0x01: // 16BIT
objidx = *((const uint16 *) entryptr) - 1;
entryptr += 2;
for (uint8 i = 0; i < numentries; i++) {
entryptr++;
lxexp->ordinal = ordinal++;
lxexp->addr = ((uint8 *) retval->mmaps[objidx].addr) + *((const uint16 *) entryptr);
lxexp->object = &retval->mmaps[objidx];
lxexp++;
entryptr += 2;
} // for
break;
case 0x03: // 32BIT
objidx = *((const uint16 *) entryptr) - 1;
entryptr += 2;
for (uint8 i = 0; i < numentries; i++) {
entryptr++;
lxexp->ordinal = ordinal++;
lxexp->addr = ((uint8 *) retval->mmaps[objidx].addr) + *((const uint32 *) entryptr);
lxexp->object = &retval->mmaps[objidx];
lxexp++;
entryptr += 4;
}
break;
case 0x02: // 286CALLGATE
case 0x04: // FORWARDER
fprintf(stderr, "WRITE ME %s:%d\n", __FILE__, __LINE__);
goto loadlx_failed;
default:
fprintf(stderr, "UNKNOWN ENTRY TYPE (%u)\n\n", (uint) bundletype);
goto loadlx_failed;
} // switch
} // while
retval->num_exports = (uint32) (lxexp - retval->exports);
// Now load named entry points.
if (lx->resident_name_table_offset) {
if (!loadLxNameTable(retval, exe + lx->resident_name_table_offset))
goto loadlx_failed;
} // if
if (lx->non_resident_name_table_offset && lx->non_resident_name_table_len) {
if (!loadLxNameTable(retval, origexe + lx->non_resident_name_table_offset))
goto loadlx_failed;
} // if
// Load other dependencies of this module.
const uint8 *import_modules_table = exe + lx->import_module_table_offset;
for (uint32 i = 0; i < lx->num_import_mod_entries; i++) {
const uint8 namelen = *(import_modules_table++);
if (namelen > 127) {
fprintf(stderr, "Import module %u name is > 127 chars (%u). Corrupt file or bug!\n", (uint) (i + 1), (uint) namelen);
goto loadlx_failed;
}
char name[128];
memcpy(name, import_modules_table, namelen);
import_modules_table += namelen;
name[namelen] = '\0';
retval->dependencies[i] = loadLxModuleByModuleNameInternal(name, dependency_tree_depth);
if (!retval->dependencies[i]) {
fprintf(stderr, "Failed to load dependency '%s' for module '%s'\n", name, modname);
goto loadlx_failed;
} // if
} // for
// Run through again and do all the fixups...
obj = ((const LxObjectTableEntry *) (exe + lx->object_table_offset));
for (uint32 i = 0; i < lx->module_num_objects; i++, obj++) {
if (obj->object_flags & 0x8) // !!! FIXME: resource object; ignore this until resource support is written, later.
continue;
uint8 *dst = (uint8 *) retval->mmaps[i].addr;
const uint32 numPageTableEntries = obj->num_page_table_entries;
for (uint32 pagenum = 0; pagenum < numPageTableEntries; pagenum++) {
fixupPage(exe, retval, obj, pagenum, dst);
dst += lx->page_size;
} // for
// !!! FIXME: hack to nop out some 16-bit code in emx.dll startup...
if ((i == 1) && (strcasecmp(modname, "EMX") == 0)) {
// This is the 16-bit signal handler installer. nop it out.
uint8 *ptr = ((uint8 *) retval->mmaps[1].addr) + 28596;
for (uint32 j = 0; j < 37; j++)
*(ptr++) = 0x90; // nop
} // if
// !!! FIXME: hack for Java that fails to mark a code page as executable
// !!! FIXME: (on 386 machines, read implies execute, so this error could go unnoticed).
uint32 object_flags = obj->object_flags;
if ((i == 4) && (strcasecmp(modname, "HPI") == 0)) {
fprintf(stderr, "fixed page permissions to workaround bug in Java DLL\n");
object_flags |= 0x4;
} // if
// Now set all the pages of this object to the proper final permissions...
const int prot = ((object_flags & 0x1) ? PROT_READ : 0) |
((object_flags & 0x2) ? PROT_WRITE : 0) |
((object_flags & 0x4) ? PROT_EXEC : 0);
retval->mmaps[i].prot = prot;
if (mprotect(retval->mmaps[i].mapped, retval->mmaps[i].size, prot) == -1) {
fprintf(stderr, "mprotect(%p, %u, %s%s%s, ANON|PRIVATE|FIXED, -1, 0) failed (%d): %s\n",
retval->mmaps[i].addr, (uint) retval->mmaps[i].size,
(prot&PROT_READ) ? "R" : "-",
(prot&PROT_WRITE) ? "W" : "-",
(prot&PROT_EXEC) ? "X" : "-",
errno, strerror(errno));
goto loadlx_failed;
} // if
} // for
retval->os2path = makeOS2Path(fname);
if (!retval->os2path)
goto loadlx_failed;
if (!isDLL) {
retval->initialized = 1;
} else {
// call library init code...
assert(GLoaderState->main_module != NULL);
assert(GLoaderState->main_module != retval);
runLxLibraryInit(retval);
retval->initialized = 1;
// module is ready to use, put it in the loaded list.
// !!! FIXME: mutex this
if (GLoaderState->loaded_modules) {
retval->next = GLoaderState->loaded_modules;
GLoaderState->loaded_modules->prev = retval;
} // if
GLoaderState->loaded_modules = retval;
} // if
return retval;
loadlx_failed:
freeLxModule(retval);
return NULL;
} // loadLxModule
static LxModule *loadLxModuleByPathInternal(const char *fname, const int dependency_tree_depth)
{
const char *what = NULL; (void) what;
uint8 *module = NULL;
uint32 modulelen = 0;
FILE *io = NULL;
// !!! FIXME: locate correct file (case-insensitive checking, convert '\\' to '/' etc)...
#define LOADFAIL(x) { what = x; goto loadmod_failed; }
if ((io = fopen(fname, "rb")) == NULL) LOADFAIL("open");
if (fseek(io, 0, SEEK_END) < 0) LOADFAIL("seek");
modulelen = ftell(io);
if ((module = (uint8 *) malloc(modulelen)) == NULL) LOADFAIL("malloc");
rewind(io);
if (fread(module, modulelen, 1, io) != 1) LOADFAIL("read");
fclose(io);
#undef LOADFAIL
LxModule *retval = loadLxModule(fname, module, modulelen, dependency_tree_depth);
free(module);
return retval;
loadmod_failed:
fprintf(stderr, "%s failure on '%s: %s'\n", what, fname, strerror(errno));
if (io)
fclose(io);
free(module);
return NULL;
} // loadLxModuleByPathInternal
static inline LxModule *loadLxModuleByPath(const char *fname)
{
return loadLxModuleByPathInternal(fname, 0);
} // loadLxModuleByPath
static LxModule *loadNativeModule(const char *fname, const char *modname)
{
LxModule *retval = (LxModule *) malloc(sizeof (LxModule));
void *lib = NULL;
LxNativeModuleInitEntryPoint fn = NULL;
const LxExport *exports = NULL;
uint32 num_exports = 0;
char *os2path = makeOS2Path(fname);
if (!retval || !modname || !os2path)
goto loadnative_failed;
memset(retval, '\0', sizeof(*retval));
// !!! FIXME: mutex this.
lib = dlopen(fname, RTLD_LOCAL | RTLD_NOW);
if (lib == NULL) {
fprintf(stderr, "dlopen('%s') failed: %s\n", fname, dlerror());
goto loadnative_failed;
} // if
fn = (LxNativeModuleInitEntryPoint) dlsym(lib, "lxNativeModuleInit");
if (!fn)
goto loadnative_failed;
exports = fn(GLoaderState, &num_exports);
if (!exports)
goto loadnative_failed;
retval->refcount = 1;
strcpy(retval->name, modname);
retval->nativelib = lib;
retval->os2path = os2path;
retval->exports = exports;
retval->num_exports = num_exports;
retval->initialized = 1;
//fprintf(stderr, "Loaded native module '%s' (%u exports).\n", fname, (uint) num_exports);
return retval;
loadnative_failed:
if (lib) dlclose(lib);
free(os2path);
free(retval);
return NULL;
} // loadNativeModule
static LxModule *loadLxModuleByModuleNameInternal(const char *modname, const int dependency_tree_depth)
{
// !!! FIXME: mutex this
for (LxModule *i = GLoaderState->loaded_modules; i != NULL; i = i->next) {
if (strcasecmp(i->name, modname) == 0) {
i->refcount++;
//printf("ref'd module '%s' to %u\n", i->name, (uint) i->refcount);
return i;
} // if
} // for
// !!! FIXME: decide the right path to the file, or if it's a native replacement library.
char fname[256];
snprintf(fname, sizeof (fname), "%s.dll", modname);
locatePathCaseInsensitive(fname);
LxModule *retval = NULL;
if (access(fname, F_OK) == 0)
retval = loadLxModuleByPathInternal(fname, dependency_tree_depth);
if (!retval) {
snprintf(fname, sizeof (fname), "./lib%s.so", modname);
for (char *ptr = fname; *ptr; ptr++) {
*ptr = (((*ptr >= 'A') && (*ptr <= 'Z')) ? (*ptr - ('A' - 'a')) : *ptr);
} // for
retval = loadNativeModule(fname, modname);
if (retval != NULL) {
// module is ready to use, put it in the loaded list.
// !!! FIXME: mutex this
if (GLoaderState->loaded_modules) {
retval->next = GLoaderState->loaded_modules;
GLoaderState->loaded_modules->prev = retval;
} // if
GLoaderState->loaded_modules = retval;
} // if
} // if
return retval;
} // loadLxModuleByModuleNameInternal
static void initPib(LxPIB *pib, const int argc, char **argv, char **envp)
{
// !!! FIXME: this is incomplete.
memset(pib, '\0', sizeof (*pib));
// Eventually, the environment table looks like this (double-null to terminate list): var1=a\0var2=b\0var3=c\0\0
// The command line looks like this: \0argv0\0argv1 argv2 argvN\0\0
// Between env and cmd is the exe name: argv0\0
size_t len = 1;
for (int i = 0; i < argc; i++) {
int needs_escape = 0;
int num_backslashes = 0;
for (const char *arg = argv[i]; *arg; arg++) {
const char ch = *arg;
if ((ch == ' ') || (ch == '\t'))
needs_escape = 1;
else if ((ch == '\\') || (ch == '\"'))
num_backslashes++;
len++;
} // for
if (needs_escape) {
len += 2 + num_backslashes;
} // if
len++; // terminator
} // for
len += strlen(argv[0]) + 1; // for the exe name.
const char *default_os2path = "PATH=C:\\home\\icculus\\Dropbox\\emx\\bin;C:\\WATCOM\\binp;C:\\home\\icculus"; // !!! FIXME: noooooope.
for (int i = 0; envp[i]; i++) {
const char *str = envp[i];
if (strncmp(str, "PATH=", 5) == 0) {
if (!GLoaderState->subprocess)
str = default_os2path;
} else if (strncmp(str, "IS_2INE=", 8) == 0) {
continue;
} // if
len += strlen(str) + 1;
} // for
len += 4; // null terminators.
char *env = (char *) malloc(len);
if (!env) {
fprintf(stderr, "Out of memory\n");
exit(1);
} // if
const char *libpath = NULL;
char *ptr = env;
for (int i = 0; envp[i]; i++) {
const char *str = envp[i];
if (strncmp(str, "PATH=", 5) == 0) {
if (!GLoaderState->subprocess)
str = default_os2path;
} else if (strncmp(str, "LIBPATH=", 8) == 0) {
libpath = str + 8;
} else if (strncmp(str, "IS_2INE=", 8) == 0) {
continue;
} // if
strcpy(ptr, str);
ptr += strlen(str) + 1;
}
*(ptr++) = '\0';
// we keep a copy of LIBPATH for undocumented API
// DosQueryHandleInfo(..., QHINF_LIBPATH, ...). I guess in case the app
// has changed the environment var after start? Java uses this.
if (libpath == NULL)
libpath = "";
GLoaderState->libpath = strdup(libpath);
GLoaderState->libpathlen = strlen(libpath) + 1;
// put the exe name between the environment and the command line.
strcpy(ptr, argv[0]);
ptr += strlen(argv[0]) + 1;
char *cmd = ptr;
strcpy(ptr, argv[0]);
ptr += strlen(argv[0]);
*(ptr++) = '\0';
for (int i = 1; i < argc; i++) {
int needs_escape = 0;
for (const char *arg = argv[i]; *arg; arg++) {
const char ch = *arg;
if ((ch == ' ') || (ch == '\t'))
needs_escape = 1;
} // for
if (needs_escape) {
*(ptr++) = '"';
for (const char *arg = argv[i]; *arg; arg++) {
const char ch = *arg;
if ((ch == '\\') || (ch == '\n'))
*(ptr++) = '\\';
*(ptr++) = ch;
} // for
*(ptr++) = '"';
} else {
for (const char *arg = argv[i]; *arg; arg++)
*(ptr++) = *arg;
} // if
if (i < (argc-1))
*(ptr++) = ' ';
} // for
*(ptr++) = '\0';
pib->pib_ulpid = (uint32) getpid();
pib->pib_ulppid = (uint32) getppid();
pib->pib_pchcmd = cmd;
pib->pib_pchenv = env;
//pib->pib_hmte is filled in later during loadLxModule()
// !!! FIXME: uint32 pib_flstatus;
// !!! FIXME: uint32 pib_ultype;
} // initPib
static LxModule *loadLxModuleByModuleName(const char *modname)
{
return loadLxModuleByModuleNameInternal(modname, 0);
} // loadLxModuleByModuleName
static LxModule *loadLxModuleByPathOrModuleName(const char *modname)
{
LxModule *retval = NULL;
if (!strchr(modname, '/') && !strchr(modname, '\\')) {
char *str = (char *) alloca(strlen(modname) + 1);
if (str) {
strcpy(str, modname);
char *ptr = strrchr(str, '.');
if (ptr) {
*ptr = '\0';
}
retval = loadLxModuleByModuleName(str);
} // if
} else {
uint32 err = 0;
char *path = makeUnixPath(modname, &err);
if (!path)
return NULL;
retval = loadLxModuleByPath(path);
free(path);
} // else
return retval;
} // loadLxModuleByPathOrModuleName
static __attribute__((noreturn)) void handleThreadLocalStorageAccess(const int slot, ucontext_t *uctx)
{
greg_t *gregs = uctx->uc_mcontext.gregs;
// use the segfaulting thread's FS register, so we can get its TIB2 pointer.
LxTIB2 *ptib2 = NULL;
__asm__ __volatile__ (
"pushw %%fs \n\t"
"movw %%ax, %%fs \n\t"
"movl %%fs:0xC, %%eax \n\t"
"popw %%fs \n\t"
: "=a" (ptib2)
: "eax" (gregs[REG_FS])
);
// The thread's TLS data is stored in LxPostTIB, right after its TIB2 struct.
LxPostTIB *posttib = (LxPostTIB *) (ptib2 + 1);
uint32 *tls = posttib->tls;
tls += slot;
//printf("We wanted to access thread %p TLS slot %d (currently holds %u)\n", tls - slot, slot, (uint) *tls);
static const int x86RegisterToUContextEnum[] = {
REG_EAX, REG_ECX, REG_EDX, REG_EBX, REG_ESP, REG_EBP, REG_ESI, REG_EDI
};
// this is a hack; we'll want a much more serious x86 instruction decoder before long.
int handled = 1;
uint8 *eip = (void *) (size_t) gregs[REG_EIP]; // program counter at point of segfault.
switch (eip[0]) {
case 0xC7: // mov imm16/32 -> r/m
//printf("setting TLS slot %d to imm %u.\n", slot, (uint) *((uint32 *) (eip + 2)));
*tls = *((uint32 *) (eip + 2)); // !!! FIXME: verify it's a imm32, not 16
gregs[REG_EIP] += 6;
break;
case 0x89: // mov r -> r/m
//printf("setting TLS slot %d to reg %d (%u).\n", slot, x86RegisterToUContextEnum[eip[1] >> 3], (uint) gregs[x86RegisterToUContextEnum[eip[1] >> 3]]);
*tls = (uint32) gregs[x86RegisterToUContextEnum[eip[1] >> 3]];
gregs[REG_EIP] += 2;
break;
case 0x8B: // mov r/m -> r
//printf("setting reg %d to TLS slot %d (%u).\n", (uint) x86RegisterToUContextEnum[eip[1] >> 3], slot, *tls);
gregs[x86RegisterToUContextEnum[eip[1] >> 3]] = (greg_t) *tls;
gregs[REG_EIP] += 2;
break;
default:
handled = 0;
break;
} // switch
if (!handled) {
fprintf(stderr, "Oh no, unhandled opcode 0x%X at %p accessing TLS register! File a bug!\n", (uint) eip[0], eip);
} else {
// drop out of signal handler to (hopefully) next instruction in the app,
// as if it accessed the TLS slot normally and none of this ever happened.
//printf("TLS access handler jumping back into app at %p...\n", (void *) gregs[REG_EIP]); fflush(stdout);
setcontext(uctx);
fprintf(stderr, "panic: setcontext() failed in the TLS access handler! Aborting! (%s)\n", strerror(errno));
} // else
fflush(stderr);
abort();
} // handleThreadLocalStorageAccess
static void segfault_catcher(int sig, siginfo_t *info, void *ctx)
{
ucontext_t *uctx = (ucontext_t *) ctx;
const uint32 *addr = (const uint32 *) info->si_addr;
const uint32 *tlspage = GLoaderState->tlspage;
if (tlspage && (addr >= tlspage))
{
// was the app accessing one of the OS/2 TLS slots?
const int slot = (int) (addr - tlspage);
if (slot < 32)
handleThreadLocalStorageAccess(slot, uctx);
} // if
static int faults = 0;
faults++;
switch (faults) {
// !!! FIXME: case #1 should be a much more detailed crash dump.
case 1: fprintf(stderr, "SIGSEGV at addr=%p (eip=%p)\n", addr, (void *) ((ucontext_t *) ctx)->uc_mcontext.gregs[REG_EIP]); break;
case 2: write(2, "SIGSEGV, aborting.\n", 19); break;
default: break;
} // switch
abort(); // cash out.
} // segfault_catcher
static int installSignalHandlers(void)
{
struct sigaction action;
memset(&action, '\0', sizeof (action));
action.sa_sigaction = segfault_catcher;
action.sa_flags = SA_NODEFER | SA_SIGINFO;
if (sigaction(SIGSEGV, &action, NULL) == -1) {
fprintf(stderr, "Couldn't install SIGSEGV handler! (%s)\n", strerror(errno));
return 0;
} // if
return 1;
} // installSignalHandlers
int main(int argc, char **argv, char **envp)
{
if (argc < 2) {
fprintf(stderr, "USAGE: %s <program.exe> [...programargs...]\n", argv[0]);
return 1;
}
if (!installSignalHandlers())
return 1;
if (getenv("TRACE_NATIVE"))
GLoaderState->trace_native = 1;
if (getenv("TRACE_EVENTS"))
GLoaderState->trace_events = 1;
unsigned int segment = 0;
__asm__ __volatile__ ( "movw %%cs, %%ax \n\t" : "=a" (segment) );
GLoaderState->original_cs = segment;
__asm__ __volatile__ ( "movw %%ds, %%ax \n\t" : "=a" (segment) );
GLoaderState->original_ds = segment;
__asm__ __volatile__ ( "movw %%es, %%ax \n\t" : "=a" (segment) );
GLoaderState->original_es = segment;
__asm__ __volatile__ ( "movw %%ss, %%ax \n\t" : "=a" (segment) );
GLoaderState->original_ss = segment;
const char *envr = getenv("IS_2INE");
GLoaderState->subprocess = (envr != NULL);
GLoaderState->initOs2Tib = initOs2Tib;
GLoaderState->deinitOs2Tib = deinitOs2Tib;
GLoaderState->findSelector = findSelector;
GLoaderState->freeSelector = freeSelector;
GLoaderState->convert1616to32 = convert1616to32;
GLoaderState->convert32to1616 = convert32to1616;
GLoaderState->loadModule = loadLxModuleByPathOrModuleName;
GLoaderState->locatePathCaseInsensitive = locatePathCaseInsensitive;
GLoaderState->makeUnixPath = makeUnixPath;
GLoaderState->makeOS2Path = makeOS2Path;
GLoaderState->terminate = terminate;
const char *modulename = GLoaderState->subprocess ? envr : argv[1];
// standalone, drop argv[0]. As a subprocess, keep it.
if (!GLoaderState->subprocess) {
argc--;
argv++;
} // if
initPib(&GLoaderState->pib, argc, argv, envp);
LxModule *lxmod = loadLxModuleByPath(modulename);
if (lxmod != NULL)
runLxModule(lxmod, argc, argv, envp);
return 1;
} // main
// end of lx_loader.c ...