Shm/src/shared_mem.c

195 	hd->shared_header = (struct shm_desc *) start_shared_area;
196 	hd->shared_header->mapfile = mapfile;	/* preliminary, see below */
197 	hd->shared_header->incr = incr;
198 	hd->shared_header->start = start_shared_area;
199 	hd->shared_header->lim = start_shared_area + map_default;
200 	hd->shared_header->brk = start_shared_area + sizeof(struct shm_desc);
201 	hd->shared_header->stop = start_shared_area + size;
202 	a_mutex_init(&hd->shared_header->lock);
203 	hd->heap = &hd->shared_header->heap;
204 	hd->pages = &hd->shared_header->pages;
205 	hd->shared_header->mapfile = mapfile ?
206 		strcpy(hd->shared_header->mapfile_buf, mapfile) : mapfile;
209 	hd->shared_header->processes = 1; /* done last, for synchronisation */
233 	/* preliminarily map admin page to look at the shared_header */
280 	hd->shared_header = (struct shm_desc *) start_shared_area;
281 	hd->heap = &hd->shared_header->heap;
282 	hd->pages = &hd->shared_header->pages;
283 	a_mutex_lock(&hd->shared_header->lock);
284 	hd->shared_header->processes++;
285 	a_mutex_unlock(&hd->shared_header->lock);
294     if (!hd->shared_header)
299     a_mutex_lock(&hd->shared_header->lock);
300     if (--hd->shared_header->processes == 0 && hd->shared_header->mapfile)
302 	if (unlink(hd->shared_header->mapfile) == -1 && errno != ENOENT)
307     a_mutex_unlock(&hd->shared_header->lock);
319     a_mutex_lock(&hd->shared_header->lock);
321     p = hd->shared_header->brk;
326     avail = hd->shared_header->lim - p;
329 	word needed = RoundTo(size - avail, hd->shared_header->incr);
330 	if (hd->shared_header->lim + needed > hd->shared_header->stop)
337 	if ((char *) mmap(hd->shared_header->lim, needed,
340 		(hd->shared_header->mapfile? MAP_FILE: MAP_ANONYMOUS)|
342 		(hd->shared_header->mapfile? MAP_SHARED: MAP_PRIVATE)|MAP_FIXED,
344 		(off_t) (hd->shared_header->lim - hd->shared_header->start))
345 	    != hd->shared_header->lim)
351 	hd->shared_header->lim += needed;
353     hd->shared_header->brk = p + size;
356     a_mutex_unlock(&hd->shared_header->lock);
377     if (!hd->shared_header)
382     return write(fd, hd->shared_header->start,
383 	hd->shared_header->brk - hd->shared_header->start);
397     if (!hd->shared_header)
404     start = hd->shared_header->start;
405     lim = hd->shared_header->lim;
406     processes = hd->shared_header->processes;
407     mapfile = hd->shared_header->mapfile;
409 	(void) strcpy(mapfile_buf, hd->shared_header->mapfile);
415     if (start != hd->shared_header->start)
420     hd->shared_header->processes = processes;
421     hd->shared_header->mapfile = mapfile ?
422 	    strcpy(hd->shared_header->mapfile_buf, mapfile_buf) : mapfile;
427 	hd->shared_header->lim = hd->shared_header->stop;
429     if (hd->shared_header->lim > lim)
432 	    hd->shared_header->lim - lim,
444     else if (hd->shared_header->lim < lim)
446 	if (munmap(hd->shared_header->lim, lim - hd->shared_header->lim) < 0)
454 		hd->shared_header->brk - start - sizeof(struct shm_desc));
469     if (!hd->shared_header)
471     return ptr >= (generic_ptr) hd->shared_header->start
472 	&& ptr <  (generic_ptr) hd->shared_header->brk;