diff options
Diffstat (limited to 'winsup/cygwin/shm.cc')
| -rw-r--r-- | winsup/cygwin/shm.cc | 109 |
1 files changed, 84 insertions, 25 deletions
diff --git a/winsup/cygwin/shm.cc b/winsup/cygwin/shm.cc index dbe9bb0e9..baea3a60e 100644 --- a/winsup/cygwin/shm.cc +++ b/winsup/cygwin/shm.cc @@ -1,14 +1,14 @@ /* shm.cc: Single unix specification IPC interface for Cygwin - Copyright 2001 Red Hat, Inc. +Copyright 2001, 2002 Red Hat, Inc. - Originally written by Robert Collins <robert.collins@hotmail.com> +Originally written by Robert Collins <robert.collins@hotmail.com> - This file is part of Cygwin. +This file is part of Cygwin. - This software is a copyrighted work licensed under the terms of the - Cygwin license. Please consult the file "CYGWIN_LICENSE" for - details. */ +This software is a copyrighted work licensed under the terms of the +Cygwin license. Please consult the file "CYGWIN_LICENSE" for +details. */ #include "winsup.h" #include <sys/stat.h> @@ -23,7 +23,6 @@ #include <stdio.h> #include "thread.h" #include <sys/shm.h> -#include "perprocess.h" #include "cygserver_shm.h" // FIXME IS THIS CORRECT @@ -64,9 +63,9 @@ client_request (CYGSERVER_REQUEST_SHM_GET, sizeof (parameters)) } client_request_shm::client_request_shm (key_t nkey, size_t nsize, - int nshmflg, - char psdbuf[4096], - pid_t npid): + int nshmflg, + char psdbuf[4096], + pid_t npid): client_request (CYGSERVER_REQUEST_SHM_GET, sizeof (parameters)) { buffer = (char *) ¶meters; @@ -134,6 +133,34 @@ build_inprocess_shmds (HANDLE hfilemap, HANDLE hattachmap, key_t key, return tempnode; } +static void +delete_inprocess_shmds (shmnode **nodeptr) +{ + shmnode *node = *nodeptr; + + // remove from the list + if (node == shm_head) + shm_head = shm_head->next; + else + { + shmnode *tempnode = shm_head; + while (tempnode && tempnode->next != node) + tempnode = tempnode->next; + if (tempnode) + tempnode->next = node->next; + // else log the unexpected ! + } + + // release the shared data view + UnmapViewOfFile (node->shmds); + CloseHandle (node->filemap); + CloseHandle (node->attachmap); + + // free the memory + delete node; + nodeptr = NULL; +} + int __stdcall fixup_shms_after_fork () { @@ -194,7 +221,7 @@ shmat (int shmid, const void *shmaddr, int shmflg) if (!tempnode) { /* couldn't find a currently open shm control area for the key - probably because - * shmget hasn't been called. + * shmget hasn't been called. * Allocate a new control block - this has to be handled by the daemon */ client_request_shm *req = new client_request_shm (SHM_REATTACH, shmid, GetCurrentProcessId ()); @@ -229,7 +256,7 @@ shmat (int shmid, const void *shmaddr, int shmflg) } - class shmid_ds *shm = tempnode->shmds; + // class shmid_ds *shm = tempnode->shmds; if (shmaddr) { @@ -277,10 +304,40 @@ shmdt (const void *shmaddr) /* this should be "rare" so a hefty search is ok. If this is common, then we * should alter the data structs to allow more optimisation */ - + shmnode *tempnode = shm_head; + _shmattach *attachnode; + while (tempnode) + { + // FIXME: Race potential + attachnode = tempnode->attachhead; + while (attachnode && attachnode->data != shmaddr) + attachnode = attachnode->next; + if (attachnode) + break; + tempnode = tempnode->next; + } + if (!tempnode) + { + // dt cannot be called by an app that hasn't alreadu at'd + set_errno (EINVAL); + return -1; + } + + UnmapViewOfFile (attachnode->data); + /* tell the daemon we have attached */ + client_request_shm *req = + new client_request_shm (SHM_DETACH, tempnode->shm_id); + int rc; + if ((rc = cygserver_request (req))) + { + debug_printf ("failed to tell deaemon that we have detached\n"); + } + delete req; + + return 0; } -//FIXME: who is allowed to perform STAT? +//FIXME: who is allowed to perform STAT? extern "C" int shmctl (int shmid, int cmd, struct shmid_ds *buf) { @@ -338,21 +395,20 @@ shmctl (int shmid, int cmd, struct shmid_ds *buf) break; case IPC_RMID: { - /* TODO: check permissions. Or possibly, the daemon gets to be the only + /* TODO: check permissions. Or possibly, the daemon gets to be the only * one with write access to the memory area? */ if (tempnode->shmds->shm_nattch) system_printf ("call to shmctl with cmd= IPC_RMID when memory area still has" " attachees\n"); - /* how does this work? + /* how does this work? * we mark the ds area as "deleted", and the at and get calls all fail from now on * on, when nattch becomes 0, the mapped data area is destroyed. - * and each process, as they touch this area detaches. eventually only the + * and each process, as they touch this area detaches. eventually only the * daemon has an attach. The daemon gets asked to detach immediately. */ -#if 0 -//waiting for the daemon to handle terminating process's + //waiting for the daemon to handle terminating process's client_request_shm *req = new client_request_shm (SHM_DEL, shmid, GetCurrentProcessId ()); int rc; @@ -372,8 +428,9 @@ shmctl (int shmid, int cmd, struct shmid_ds *buf) /* the daemon has deleted it's references */ /* now for us */ - -#endif + + // FIXME: create a destructor + delete_inprocess_shmds (&tempnode); } break; @@ -385,7 +442,7 @@ shmctl (int shmid, int cmd, struct shmid_ds *buf) return 0; } -/* FIXME: evaluate getuid() and getgid() against the requested mode. Then +/* FIXME: evaluate getuid32() and getgid32() against the requested mode. Then * choose PAGE_READWRITE | PAGE_READONLY and FILE_MAP_WRITE | FILE_MAP_READ * appropriately */ @@ -402,7 +459,9 @@ shmget (key_t key, size_t size, int shmflg) char sd_buf[4096]; PSECURITY_DESCRIPTOR psd = (PSECURITY_DESCRIPTOR) sd_buf; /* create a sd for our open requests based on shmflag & 0x01ff */ - psd = alloc_sd (getuid (), getgid (), cygheap->user.logsrv (), + InitializeSecurityDescriptor (psd, + SECURITY_DESCRIPTOR_REVISION); + psd = alloc_sd (getuid32 (), getgid32 (), shmflg & 0x01ff, psd, &sd_size); if (key == (key_t) - 1) @@ -479,9 +538,9 @@ shmget (key_t key, size_t size, int shmflg) #if 0 /* fill out the node data */ - shmtemp->shm_perm.cuid = getuid (); + shmtemp->shm_perm.cuid = getuid32 (); shmtemp->shm_perm.uid = shmtemp->shm_perm.cuid; - shmtemp->shm_perm.cgid = getgid (); + shmtemp->shm_perm.cgid = getgid32 (); shmtemp->shm_perm.gid = shmtemp->shm_perm.cgid; shmtemp->shm_perm.mode = shmflg & 0x01ff; shmtemp->shm_lpid = 0; |