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Bunch of work on getting java.exe to start up. Not there yet.
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Lots of fixes, improvements, and a few more APIs implemented.
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@icculus
icculus committed Oct 27, 2016
1 parent 411c204 commit 2481f59
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Showing 8 changed files with 306 additions and 55 deletions.
58 changes: 48 additions & 10 deletions lx_loader.c
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Expand Up @@ -1470,10 +1470,18 @@ static LxModule *loadLxModule(const char *fname, uint8 *exe, uint32 exelen, int
*(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 = ((obj->object_flags & 0x1) ? PROT_READ : 0) |
((obj->object_flags & 0x2) ? PROT_WRITE : 0) |
((obj->object_flags & 0x4) ? PROT_EXEC : 0);
const int prot = ((object_flags & 0x1) ? PROT_READ : 0) |
((object_flags & 0x2) ? PROT_WRITE : 0) |
((object_flags & 0x4) ? PROT_EXEC : 0);

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",
Expand Down Expand Up @@ -1692,12 +1700,15 @@ static void initPib(LxPIB *pib, const int argc, char **argv, char **envp)
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
Expand All @@ -1707,6 +1718,15 @@ static void initPib(LxPIB *pib, const int argc, char **argv, char **envp)
}
*(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;
Expand Down Expand Up @@ -1758,6 +1778,23 @@ static LxModule *loadLxModuleByModuleName(const char *modname)
return loadLxModuleByModuleNameInternal(modname, 0);
} // loadLxModuleByModuleName

static LxModule *loadLxModuleByPathOrModuleName(const char *modname)
{
LxModule *retval = NULL;
// !!! FIXME: can a module name be specified as "NAME.DLL" and not be considered a filename?
if (strrchr(modname, '.') == NULL) {
retval = loadLxModuleByModuleName(modname);
} 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;
Expand All @@ -1775,7 +1812,7 @@ static __attribute__((noreturn)) void handleThreadLocalStorageAccess(const int s
uint32 *tls = (uint32 *) (ptib2 + 1); // The thread's TLS data is stored right after its TIB2 struct.
tls += slot;

printf("We wanted to access thread %p TLS slot %d (currently holds %u)\n", tls - slot, slot, (uint) *tls);
//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
Expand All @@ -1786,19 +1823,19 @@ static __attribute__((noreturn)) void handleThreadLocalStorageAccess(const int s
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)));
//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]]);
//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 to reg %d to TLS slot %d (%u).\n", (uint) x86RegisterToUContextEnum[eip[1] >> 3], slot, *tls);
//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;
Expand All @@ -1813,7 +1850,7 @@ static __attribute__((noreturn)) void handleThreadLocalStorageAccess(const int s
} 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);
//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
Expand Down Expand Up @@ -1841,6 +1878,7 @@ static void segfault_catcher(int sig, siginfo_t *info, void *ctx)
// !!! 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.
Expand All @@ -1855,7 +1893,7 @@ static int installSignalHandlers(void)
action.sa_flags = SA_NODEFER | SA_SIGINFO;

if (sigaction(SIGSEGV, &action, NULL) == -1) {
fprintf(stderr, "Couldn't install signal handler! (%s)\n", strerror(errno));
fprintf(stderr, "Couldn't install SIGSEGV handler! (%s)\n", strerror(errno));
return 0;
} // if

Expand Down Expand Up @@ -1890,7 +1928,7 @@ int main(int argc, char **argv, char **envp)
GLoaderState->findSelector = findSelector;
GLoaderState->freeSelector = freeSelector;
GLoaderState->convert1616to32 = convert1616to32;
GLoaderState->loadModule = loadLxModuleByModuleName;
GLoaderState->loadModule = loadLxModuleByPathOrModuleName;
GLoaderState->locatePathCaseInsensitive = locatePathCaseInsensitive;
GLoaderState->makeUnixPath = makeUnixPath;
GLoaderState->makeOS2Path = makeOS2Path;
Expand Down
2 changes: 2 additions & 0 deletions lx_loader.h
View file
Expand Up @@ -215,6 +215,8 @@ typedef struct LxLoaderState
uint16 original_ss;
uint16 original_ds;
uint32 ldt[8192];
char *libpath;
uint32 libpathlen;
uint32 *tlspage;
uint32 tlsmask; // one bit for each TLS slot in use.
uint8 tlsallocs[32]; // number of TLS slots allocated in one block, indexed by starting block (zero if not the starting block).
Expand Down

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