#include "dlfcn.h"
#include "string.h"
#include "stdio.h"
#define INCL_BASE
#include <os2.h>
#include <float.h>
#include <stdlib.h>
static ULONG retcode;
static char fail[300];
static ULONG dllHandle;
static int handle_found;
static int handle_loaded;
#ifdef PERL_CORE
#include "EXTERN.h"
#include "perl.h"
#else
char *os2error(int rc);
#endif
#ifdef DLOPEN_INITTERM
unsigned long _DLL_InitTerm(unsigned long modHandle, unsigned long flag)
{
switch (flag) {
case 0: /* INIT */
/* Save handle */
dllHandle = modHandle;
handle_found = 1;
return TRUE;
case 1: /* TERM */
handle_found = 0;
dllHandle = (unsigned long)NULLHANDLE;
return TRUE;
}
return FALSE;
}
#endif
HMODULE
find_myself(void)
{
static APIRET APIENTRY (*pDosQueryModFromEIP) (HMODULE * hmod, ULONG * obj, ULONG BufLen, PCHAR Buf,
ULONG * Offset, ULONG Address);
HMODULE doscalls_h, mod;
static int failed;
ULONG obj, offset, rc;
char buf[260];
if (failed)
return 0;
failed = 1;
doscalls_h = (HMODULE)dlopen("DOSCALLS",0);
if (!doscalls_h)
return 0;
/* {&doscalls_handle, NULL, 360}, */ /* DosQueryModFromEIP */
rc = DosQueryProcAddr(doscalls_h, 360, 0, (PFN*)&pDosQueryModFromEIP);
if (rc)
return 0;
rc = pDosQueryModFromEIP(&mod, &obj, sizeof(buf), buf, &offset, (ULONG)dlopen);
if (rc)
return 0;
failed = 0;
handle_found = 1;
dllHandle = mod;
return mod;
}
void *
dlopen(const char *path, int mode)
{
HMODULE handle;
char tmp[260];
const char *beg, *dot;
ULONG rc;
unsigned fpflag = _control87(0,0);
fail[0] = 0;
if (!path) { /* Our own handle. */
if (handle_found || find_myself()) {
char dllname[260];
if (handle_loaded)
return (void*)dllHandle;
rc = DosQueryModuleName(dllHandle, sizeof(dllname), dllname);
if (rc) {
strcpy(fail, "can't find my DLL name by the handle");
retcode = rc;
return 0;
}
rc = DosLoadModule(fail, sizeof fail, dllname, &handle);
if (rc) {
strcpy(fail, "can't load my own DLL");
retcode = rc;
return 0;
}
handle_loaded = 1;
goto ret;
}
retcode = ERROR_MOD_NOT_FOUND;
strcpy(fail, "can't load from myself: compiled without -DDLOPEN_INITTERM");
return 0;
}
if ((rc = DosLoadModule(fail, sizeof fail, (char*)path, &handle)) == 0)
goto ret;
retcode = rc;
if (strlen(path) >= sizeof(tmp))
return NULL;
/* Not found. Check for non-FAT name and try truncated name. */
/* Don't know if this helps though... */
for (beg = dot = path + strlen(path);
beg > path && !strchr(":/\\", *(beg-1));
beg--)
if (*beg == '.')
dot = beg;
if (dot - beg > 8) {
int n = beg+8-path;
memmove(tmp, path, n);
memmove(tmp+n, dot, strlen(dot)+1);
if (DosLoadModule(fail, sizeof fail, tmp, &handle) == 0)
goto ret;
}
handle = 0;
ret:
_control87(fpflag, MCW_EM); /* Some modules reset FP flags on load */
return (void *)handle;
}
#define ERROR_WRONG_PROCTYPE 0xffffffff
void *
dlsym(void *handle, const char *symbol)
{
ULONG rc, type;
PFN addr;
fail[0] = 0;
rc = DosQueryProcAddr((HMODULE)handle, 0, symbol, &addr);
if (rc == 0) {
rc = DosQueryProcType((HMODULE)handle, 0, symbol, &type);
if (rc == 0 && type == PT_32BIT)
return (void *)addr;
rc = ERROR_WRONG_PROCTYPE;
}
retcode = rc;
return NULL;
}
char *
dlerror(void)
{
static char buf[700];
ULONG len;
char *err;
if (retcode == 0)
return NULL;
if (retcode == ERROR_WRONG_PROCTYPE)
err = "Wrong procedure type";
else
err = os2error(retcode);
len = strlen(err);
if (len > sizeof(buf) - 1)
len = sizeof(buf) - 1;
strncpy(buf, err, len+1);
if (fail[0] && len + strlen(fail) < sizeof(buf) - 100)
sprintf(buf + len, ", possible problematic module: '%s'", fail);
retcode = 0;
return buf;
}
int
dlclose(void *handle)
{
ULONG rc;
if ((rc = DosFreeModule((HMODULE)handle)) == 0) return 0;
retcode = rc;
return 2;
}