1
2/* Support for dynamic loading of extension modules */
3
4#include <kernel/image.h>
5#include <kernel/OS.h>
6#include <stdlib.h>
7
8#include "Python.h"
9#include "importdl.h"
10
11const struct filedescr _PyImport_DynLoadFiletab[] = {
12    {".so", "rb", C_EXTENSION},
13    {"module.so", "rb", C_EXTENSION},
14    {0, 0}
15};
16
17#if defined(MAXPATHLEN) && !defined(_SYS_PARAM_H)
18#undef MAXPATHLEN
19#endif
20
21#ifdef WITH_THREAD
22#include "pythread.h"
23static PyThread_type_lock beos_dyn_lock;
24#endif
25
26static PyObject *beos_dyn_images = NULL;
27
28/* ----------------------------------------------------------------------
29 * BeOS dynamic loading support
30 *
31 * This uses shared libraries, but BeOS has its own way of doing things
32 * (much easier than dlfnc.h, from the look of things).  We'll use a
33 * Python Dictionary object to store the images_ids so we can be very
34 * nice and unload them when we exit.
35 *
36 * Note that this is thread-safe.  Probably irrelevent, because of losing
37 * systems... Python probably disables threads while loading modules.
38 * Note the use of "probably"!  Better to be safe than sorry. [chrish]
39 *
40 * As of 1.5.1 this should also work properly when you've configured
41 * Python without thread support; the 1.5 version required it, which wasn't
42 * very friendly.  Note that I haven't tested it without threading... why
43 * would you want to avoid threads on BeOS? [chrish]
44 *
45 * As of 1.5.2, the PyImport_BeImageID() function has been removed; Donn
46 * tells me it's not necessary anymore because of PyCObject_Import().
47 * [chrish]
48 */
49
50/* Whack an item; the item is an image_id in disguise, so we'll call
51 * unload_add_on() for it.
52 */
53static void beos_nuke_dyn( PyObject *item )
54{
55    status_t retval;
56
57    if( item ) {
58        image_id id = (image_id)PyInt_AsLong( item );
59
60        retval = unload_add_on( id );
61    }
62}
63
64/* atexit() handler that'll call unload_add_on() for every item in the
65 * dictionary.
66 */
67static void beos_cleanup_dyn( void )
68{
69    if( beos_dyn_images ) {
70        int idx;
71        int list_size;
72        PyObject *id_list;
73
74#ifdef WITH_THREAD
75        PyThread_acquire_lock( beos_dyn_lock, 1 );
76#endif
77
78        id_list = PyDict_Values( beos_dyn_images );
79
80        list_size = PyList_Size( id_list );
81        for( idx = 0; idx < list_size; idx++ ) {
82            PyObject *the_item;
83
84            the_item = PyList_GetItem( id_list, idx );
85            beos_nuke_dyn( the_item );
86        }
87
88        PyDict_Clear( beos_dyn_images );
89
90#ifdef WITH_THREAD
91        PyThread_free_lock( beos_dyn_lock );
92#endif
93    }
94}
95
96/*
97 * Initialize our dictionary, and the dictionary mutex.
98 */
99static void beos_init_dyn( void )
100{
101    /* We're protected from a race condition here by the atomic init_count
102     * variable.
103     */
104    static int32 init_count = 0;
105    int32 val;
106
107    val = atomic_add( &init_count, 1 );
108    if( beos_dyn_images == NULL && val == 0 ) {
109        beos_dyn_images = PyDict_New();
110#ifdef WITH_THREAD
111        beos_dyn_lock = PyThread_allocate_lock();
112#endif
113        atexit( beos_cleanup_dyn );
114    }
115}
116
117/*
118 * Add an image_id to the dictionary; the module name of the loaded image
119 * is the key.  Note that if the key is already in the dict, we unload
120 * that image; this should allow reload() to work on dynamically loaded
121 * modules (super-keen!).
122 */
123static void beos_add_dyn( char *name, image_id id )
124{
125    int retval;
126    PyObject *py_id;
127
128    if( beos_dyn_images == NULL ) {
129        beos_init_dyn();
130    }
131
132#ifdef WITH_THREAD
133    retval = PyThread_acquire_lock( beos_dyn_lock, 1 );
134#endif
135
136    /* If there's already an object with this key in the dictionary,
137     * we're doing a reload(), so let's nuke it.
138     */
139    py_id = PyDict_GetItemString( beos_dyn_images, name );
140    if( py_id ) {
141        beos_nuke_dyn( py_id );
142        retval = PyDict_DelItemString( beos_dyn_images, name );
143    }
144
145    py_id = PyInt_FromLong( (long)id );
146    if( py_id ) {
147        retval = PyDict_SetItemString( beos_dyn_images, name, py_id );
148    }
149
150#ifdef WITH_THREAD
151    PyThread_release_lock( beos_dyn_lock );
152#endif
153}
154
155
156
157dl_funcptr _PyImport_GetDynLoadFunc(const char *fqname, const char *shortname,
158                                    const char *pathname, FILE *fp)
159{
160    dl_funcptr p;
161    image_id the_id;
162    status_t retval;
163    char fullpath[PATH_MAX];
164    char funcname[258];
165
166    if( Py_VerboseFlag ) {
167        printf( "load_add_on( %s )\n", pathname );
168    }
169
170    /* Hmm, this old bug appears to have regenerated itself; if the
171     * path isn't absolute, load_add_on() will fail.  Reported to Be
172     * April 21, 1998.
173     */
174    if( pathname[0] != '/' ) {
175        (void)getcwd( fullpath, PATH_MAX );
176        (void)strncat( fullpath, "/", PATH_MAX );
177        (void)strncat( fullpath, pathname, PATH_MAX );
178
179        if( Py_VerboseFlag ) {
180            printf( "load_add_on( %s )\n", fullpath );
181        }
182    } else {
183        (void)strcpy( fullpath, pathname );
184    }
185
186    the_id = load_add_on( fullpath );
187    if( the_id < B_NO_ERROR ) {
188        /* It's too bad load_add_on() doesn't set errno or something...
189         */
190        char buff[256];  /* hate hard-coded string sizes... */
191
192        if( Py_VerboseFlag ) {
193            printf( "load_add_on( %s ) failed", fullpath );
194        }
195
196        if( the_id == B_ERROR )
197            PyOS_snprintf( buff, sizeof(buff),
198                           "BeOS: Failed to load %.200s",
199                           fullpath );
200        else
201            PyOS_snprintf( buff, sizeof(buff),
202                           "Unknown error loading %.200s",
203                           fullpath );
204
205        PyErr_SetString( PyExc_ImportError, buff );
206        return NULL;
207    }
208
209    PyOS_snprintf(funcname, sizeof(funcname), "init%.200s", shortname);
210    if( Py_VerboseFlag ) {
211        printf( "get_image_symbol( %s )\n", funcname );
212    }
213
214    retval = get_image_symbol( the_id, funcname, B_SYMBOL_TYPE_TEXT, &p );
215    if( retval != B_NO_ERROR || p == NULL ) {
216        /* That's bad, we can't find that symbol in the module...
217         */
218        char buff[256];  /* hate hard-coded string sizes... */
219
220        if( Py_VerboseFlag ) {
221            printf( "get_image_symbol( %s ) failed", funcname );
222        }
223
224        switch( retval ) {
225        case B_BAD_IMAGE_ID:
226            PyOS_snprintf( buff, sizeof(buff),
227                   "can't load init function for dynamic module: "
228                   "Invalid image ID for %.180s", fullpath );
229            break;
230        case B_BAD_INDEX:
231            PyOS_snprintf( buff, sizeof(buff),
232                   "can't load init function for dynamic module: "
233                   "Bad index for %.180s", funcname );
234            break;
235        default:
236            PyOS_snprintf( buff, sizeof(buff),
237                   "can't load init function for dynamic module: "
238                   "Unknown error looking up %.180s", funcname );
239            break;
240        }
241
242        retval = unload_add_on( the_id );
243
244        PyErr_SetString( PyExc_ImportError, buff );
245        return NULL;
246    }
247
248    /* Save the module name and image ID for later so we can clean up
249     * gracefully.
250     */
251    beos_add_dyn( fqname, the_id );
252
253    return p;
254}
255