Python/dynload_mac.c

   1
   2 /* Support for dynamic loading of extension modules */
   3
   4 #include "Python.h"
   5 #include "importdl.h"
   6
   7 #include <Aliases.h>
   8 #include <CodeFragments.h>
   9 #ifdef USE_GUSI1
  10 #include "TFileSpec.h"          /* for Path2FSSpec() */
  11 #endif
  12 #include <Files.h>
  13 #include <TextUtils.h>
  14 #include "macdefs.h"
  15 #include "macglue.h"
  16
  17
  18 const struct filedescr _PyImport_DynLoadFiletab[] = {
  19         {".slb", "rb", C_EXTENSION},
  20 #ifdef __CFM68K__
  21         {".CFM68K.slb", "rb", C_EXTENSION},
  22 #else
  23 #if TARGET_API_MAC_CARBON
  24         {".carbon.slb", "rb", C_EXTENSION},
  25 #else
  26         {".ppc.slb", "rb", C_EXTENSION},
  27 #endif
  28 #endif
  29         {0, 0}
  30 };
  31
  32
  33 dl_funcptr _PyImport_GetDynLoadFunc(const char *fqname, const char *shortname,
  34                                     const char *pathname, FILE *fp)
  35 {
  36         dl_funcptr p;
  37         char funcname[258];
  38
  39         /*
  40         ** Dynamic loading of CFM shared libraries on the Mac.  The
  41         ** code has become more convoluted than it was, because we
  42         ** want to be able to put multiple modules in a single
  43         ** file. For this reason, we have to determine the fragment
  44         ** name, and we cannot use the library entry point but we have
  45         ** to locate the correct init routine "by hand".
  46         */
  47         FSSpec libspec;
  48         CFragConnectionID connID;
  49         Ptr mainAddr;
  50         Str255 errMessage;
  51         OSErr err;
  52 #ifndef USE_GUSI1
  53         Boolean isfolder, didsomething;
  54 #endif
  55         char buf[512];
  56         Str63 fragname;
  57         Ptr symAddr;
  58         CFragSymbolClass class;
  59
  60         /* First resolve any aliases to find the real file */
  61 #ifdef USE_GUSI1
  62         err = Path2FSSpec(pathname, &libspec);
  63 #else
  64         c2pstrcpy((unsigned char *)buf, pathname);
  65         (void)FSMakeFSSpec(0, 0, (unsigned char *)buf, &libspec);
  66         err = ResolveAliasFile(&libspec, 1, &isfolder, &didsomething);
  67 #endif
  68         if ( err ) {
  69                 PyOS_snprintf(buf, sizeof(buf),
  70                               "%.200s: %.200s", pathname, PyMac_StrError(err));
  71                 PyErr_SetString(PyExc_ImportError, buf);
  72                 return NULL;
  73         }
  74         /* Next, determine the fragment name,
  75            by stripping '.slb' and 'module' */
  76         memcpy(fragname+1, libspec.name+1, libspec.name[0]);
  77         fragname[0] = libspec.name[0];
  78         if( strncmp((char *)(fragname+1+fragname[0]-4),
  79                     ".slb", 4) == 0 )
  80                 fragname[0] -= 4;
  81         if ( strncmp((char *)(fragname+1+fragname[0]-6),
  82                      "module", 6) == 0 )
  83                 fragname[0] -= 6;
  84         /* Load the fragment
  85            (or return the connID if it is already loaded */
  86         err = GetDiskFragment(&libspec, 0, 0, fragname,
  87                               kLoadCFrag, &connID, &mainAddr,
  88                               errMessage);
  89         if ( err == cfragImportTooOldErr || err == cfragImportTooNewErr ) {
  90                 /*
  91                 ** Special-case code: if PythonCore is too old or too new this means
  92                 ** the dynamic module was meant for a different Python.
  93                 */
  94                 if (errMessage[0] == 10 && strncmp((char *)errMessage+1, "PythonCore", 10) == 0 ) {
  95                         PyOS_snprintf(buf, sizeof(buf),
  96                       "Dynamic module was built for %s version of MacPython",
  97                       (err == cfragImportTooOldErr ? "a newer" : "an older"));
  98                         PyErr_SetString(PyExc_ImportError, buf);
  99                         return NULL;
 100                 }
 101         }
 102         if ( err ) {
 103                 PyOS_snprintf(buf, sizeof(buf), "%.*s: %.200s",
 104                         errMessage[0], errMessage+1,
 105                         PyMac_StrError(err));
 106                 PyErr_SetString(PyExc_ImportError, buf);
 107                 return NULL;
 108         }
 109         /* Locate the address of the correct init function */
 110         PyOS_snprintf(funcname, sizeof(funcname), "init%.200s", shortname);
 111         err = FindSymbol(connID, Pstring(funcname), &symAddr, &class);
 112         if ( err ) {
 113                 PyOS_snprintf(buf, sizeof(buf), "%s: %.200s",
 114                               funcname, PyMac_StrError(err));
 115                 PyErr_SetString(PyExc_ImportError, buf);
 116                 return NULL;
 117         }
 118         p = (dl_funcptr)symAddr;
 119
 120         return p;
 121 }