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mirror of https://github.com/python/cpython.git synced 2024-12-01 11:15:56 +01:00
cpython/PC/import_nt.c
Guido van Rossum 271f977686 Seem to be some changes related to DLL version from string resource,
again (Mark Hammond is the cause of all this).
1997-09-29 23:39:31 +00:00

76 lines
2.3 KiB
C

/********************************************************************
import_nt.c
Win32 specific import code.
*/
#include "Python.h"
#include "osdefs.h"
#include <windows.h>
#include "importdl.h"
#include "malloc.h" // for alloca
extern const char *PyWin_DLLVersionString; // a string loaded from the DLL at startup.
/* Return whether this is Win32s, i.e., Win32 API on Win 3.1(1).
This function is exported! */
BOOL PyWin_IsWin32s()
{
static BOOL bIsWin32s = -1; /* flag as "not yet looked" */
if (bIsWin32s == -1) {
OSVERSIONINFO ver;
ver.dwOSVersionInfoSize = sizeof(ver);
GetVersionEx(&ver);
bIsWin32s = ver.dwPlatformId == VER_PLATFORM_WIN32s;
}
return bIsWin32s;
}
FILE *PyWin_FindRegisteredModule( const char *moduleName, struct filedescr **ppFileDesc, char *pathBuf, int pathLen)
{
char *moduleKey;
char *pos;
const char keyPrefix[] = "Software\\Python\\PythonCore\\";
const char keySuffix[] = "\\Modules\\";
struct filedescr *fdp = NULL;
FILE *fp;
int modNameSize = pathLen;
int versionLen, moduleLen;
HKEY keyBase = PyWin_IsWin32s() ? HKEY_CLASSES_ROOT : HKEY_LOCAL_MACHINE;
// conceptually, this code is setting up:
// sprintf(buf, "Software\\Python\\PythonCore\\%s\\Modules\\%s", PyWin_DLLVersionString, moduleName);
// the sprintf would be clearer, but slower and less "length-safe"
versionLen = strlen(PyWin_DLLVersionString);
moduleLen = strlen(moduleName);
// alloca == no free required, but memory only local to fn, also no heap fragmentation!
moduleKey = alloca(sizeof(keyPrefix)-1 + versionLen + sizeof(keySuffix) + moduleLen); // chars only, plus 1 NULL.
pos = moduleKey;
memcpy(pos, keyPrefix, sizeof(keyPrefix)-1);
pos += sizeof(keyPrefix)-1;
memcpy(pos, PyWin_DLLVersionString, versionLen);
pos +=versionLen;
memcpy(pos, keySuffix, sizeof(keySuffix));
pos += sizeof(keySuffix)-1;
memcpy(pos, moduleName, moduleLen+1); // NULL comes with this one!
if (RegQueryValue(keyBase, moduleKey, pathBuf, &modNameSize)!=ERROR_SUCCESS)
return NULL;
// use the file extension to locate the type entry.
for (fdp = _PyImport_Filetab; fdp->suffix != NULL; fdp++) {
int extLen=strlen(fdp->suffix);
if (modNameSize>extLen && strnicmp(pathBuf+(modNameSize-extLen-1),fdp->suffix,extLen)==0)
break;
}
if (fdp->suffix==NULL)
return NULL;
fp = fopen(pathBuf, fdp->mode);
if (fp != NULL)
*ppFileDesc = fdp;
return fp;
}