cpython/Python/dynload_win.c

/* Support for dynamic loading of extension modules */

#include <windows.h>
#include <direct.h>

#include "Python.h"
#include "importdl.h"

const struct filedescr _PyImport_DynLoadFiletab[] = {
#ifdef _DEBUG
	{"_d.pyd", "rb", C_EXTENSION},
	{"_d.dll", "rb", C_EXTENSION},
#else
	{".pyd", "rb", C_EXTENSION},
	{".dll", "rb", C_EXTENSION},
#endif
	{0, 0}
};


dl_funcptr _PyImport_GetDynLoadFunc(const char *fqname, const char *shortname,
				    const char *pathname, FILE *fp)
{
	dl_funcptr p;
	char funcname[258];

	sprintf(funcname, "init%.200s", shortname);

#ifdef MS_WIN32
	{
		HINSTANCE hDLL;
		char pathbuf[260];
		if (strchr(pathname, '\\') == NULL &&
		    strchr(pathname, '/') == NULL)
		{
			/* Prefix bare filename with ".\" */
			char *p = pathbuf;
			*p = '\0';
			_getcwd(pathbuf, sizeof pathbuf);
			if (*p != '\0' && p[1] == ':')
				p += 2;
			sprintf(p, ".\\%-.255s", pathname);
			pathname = pathbuf;
		}
		/* Look for dependent DLLs in directory of pathname first */
		/* XXX This call doesn't exist in Windows CE */
		hDLL = LoadLibraryEx(pathname, NULL,
				     LOAD_WITH_ALTERED_SEARCH_PATH);
		if (hDLL==NULL){
			char errBuf[256];
			unsigned int errorCode;

			/* Get an error string from Win32 error code */
			char theInfo[256]; /* Pointer to error text
					      from system */
			int theLength; /* Length of error text */

			errorCode = GetLastError();

			theLength = FormatMessage(
				FORMAT_MESSAGE_FROM_SYSTEM, /* flags */
				NULL, /* message source */
				errorCode, /* the message (error) ID */
				0, /* default language environment */
				(LPTSTR) theInfo, /* the buffer */
				sizeof(theInfo), /* the buffer size */
				NULL); /* no additional format args. */

			/* Problem: could not get the error message.
			   This should not happen if called correctly. */
			if (theLength == 0) {
				sprintf(errBuf,
					"DLL load failed with error code %d",
					errorCode);
			} else {
				size_t len;
				/* For some reason a \r\n
				   is appended to the text */
				if (theLength >= 2 &&
				    theInfo[theLength-2] == '\r' &&
				    theInfo[theLength-1] == '\n') {
					theLength -= 2;
					theInfo[theLength] = '\0';
				}
				strcpy(errBuf, "DLL load failed: ");
				len = strlen(errBuf);
				strncpy(errBuf+len, theInfo,
					sizeof(errBuf)-len);
				errBuf[sizeof(errBuf)-1] = '\0';
			}
			PyErr_SetString(PyExc_ImportError, errBuf);
		return NULL;
		}
		p = GetProcAddress(hDLL, funcname);
	}
#endif /* MS_WIN32 */
#ifdef MS_WIN16
	{
		HINSTANCE hDLL;
		char pathbuf[16];
		if (strchr(pathname, '\\') == NULL &&
		    strchr(pathname, '/') == NULL)
		{
			/* Prefix bare filename with ".\" */
			sprintf(pathbuf, ".\\%-.13s", pathname);
			pathname = pathbuf;
		}
		hDLL = LoadLibrary(pathname);
		if (hDLL < HINSTANCE_ERROR){
			char errBuf[256];
			sprintf(errBuf,
				"DLL load failed with error code %d", hDLL);
			PyErr_SetString(PyExc_ImportError, errBuf);
			return NULL;
		}
		p = GetProcAddress(hDLL, funcname);
	}
#endif /* MS_WIN16 */

	return p;
}