/* A template function which creates/attaches shm seg handle
* to the shared memory. Used by user-exposed functions below
*/
static inline int MPL_shm_seg_create_attach_templ(MPL_shm_hnd_t hnd, intptr_t seg_sz,
void **shm_addr_ptr, int offset, int flag)
{
HANDLE lhnd = INVALID_HANDLE_VALUE;
int rc = MPL_SHM_SUCCESS;
ULARGE_INTEGER seg_sz_large;
seg_sz_large.QuadPart = seg_sz;
if (!MPLI_shm_ghnd_is_valid(hnd)) {
rc = MPLI_shm_ghnd_set_uniq(hnd);
if (rc) {
goto fn_exit;
}
}
if (flag & MPLI_SHM_FLAG_SHM_CREATE) {
lhnd = CreateFileMapping(INVALID_HANDLE_VALUE, NULL,
PAGE_READWRITE, seg_sz_large.HighPart, seg_sz_large.LowPart,
MPLI_shm_ghnd_get_by_ref(hnd));
if (lhnd == NULL) {
rc = MPL_SHM_EINTERN;
goto fn_exit;
}
MPLI_shm_lhnd_set(hnd, lhnd);
} else {
if (!MPLI_shm_lhnd_is_valid(hnd)) {
/* Strangely OpenFileMapping() returns NULL on error! */
lhnd = OpenFileMapping(FILE_MAP_WRITE, FALSE, MPLI_shm_ghnd_get_by_ref(hnd));
if (lhnd == NULL) {
rc = MPL_SHM_EINTERN;
goto fn_exit;
}
MPLI_shm_lhnd_set(hnd, lhnd);
}
}
if (flag & MPLI_SHM_FLAG_SHM_ATTACH) {
if (flag & MPLI_SHM_FLAG_FIXED_ADDR) {
void *start_addr = (void *) *shm_addr_ptr;
/* The start_addr must be a multiple of the system's memory allocation granularity,
* or the function fails. To determine the memory allocation granularity of the system,
* use the GetSystemInfo function. If there is not enough address space at the
* specified address, the function fails.
* If the function fails, the return value is NULL.*/
*shm_addr_ptr = MapViewOfFileEx(MPLI_shm_lhnd_get(hnd),
FILE_MAP_WRITE, 0, offset, 0, start_addr);
} else {
*shm_addr_ptr = MapViewOfFile(MPLI_shm_lhnd_get(hnd), FILE_MAP_WRITE, 0, offset, 0);
}
if (*shm_addr_ptr == NULL) {
rc = MPL_SHM_EINVAL;
}
}
fn_exit:
return rc;
}
/* Remove a shared memory segment
* hnd : Handle to the shared memory segment to be removed
*/
int MPL_shm_seg_remove(MPL_shm_hnd_t hnd)
{
struct shmid_ds ds;
int rc = -1;
rc = shmctl(MPLI_shm_lhnd_get(hnd), IPC_RMID, &ds);
return (rc == 0) ? MPL_SHM_SUCCESS : MPL_SHM_EINTERN;
}
inline int MPLI_shm_lhnd_close(MPL_shm_hnd_t hnd)
{
MPLI_shm_lhnd_t lhnd = MPLI_SHM_LHND_INVALID;
lhnd = MPLI_shm_lhnd_get(hnd);
if (lhnd != MPLI_SHM_LHND_INVALID) {
if (close(lhnd) == 0) {
MPLI_shm_lhnd_set(hnd, MPLI_SHM_LHND_INIT_VAL);
} else {
/* close() failed */
return -1;
}
}
return 0;
}
/* A template function which creates/attaches shm seg handle
* to the shared memory. Used by user-exposed functions below
*/
static inline int MPL_shm_seg_create_attach_templ(MPL_shm_hnd_t hnd, intptr_t seg_sz,
void **shm_addr_ptr, int offset, int flag)
{
int rc = MPL_SHM_SUCCESS;
int lhnd = -1;
if (flag & MPLI_SHM_FLAG_SHM_CREATE) {
lhnd = shmget(IPC_PRIVATE, seg_sz, IPC_CREAT | S_IRWXU);
MPLI_shm_lhnd_set(hnd, lhnd);
rc = MPLI_shm_ghnd_alloc(hnd, MPL_MEM_SHM);
if (rc) {
goto fn_exit;
}
rc = MPLI_shm_ghnd_set_by_val(hnd, "%d", lhnd);
if (rc != MPL_SHM_SUCCESS) {
goto fn_exit;
}
} else {
/* Open an existing shared memory seg */
if (!MPLI_shm_lhnd_is_valid(hnd)) {
lhnd = atoi(MPLI_shm_ghnd_get_by_ref(hnd));
MPLI_shm_lhnd_set(hnd, lhnd);
}
}
if (flag & MPLI_SHM_FLAG_SHM_ATTACH) {
const void *start_addr = NULL;
/* Caller ensures that shmaddr must be a page-aligned address
* at which the attach occurs. EINVAL error would result if a
* mapping already exists in this address range or the address
* is not page-aligned. */
if (flag & MPLI_SHM_FLAG_FIXED_ADDR)
start_addr = (const void *) *shm_addr_ptr;
/* Attach to shared mem seg */
*shm_addr_ptr = shmat(MPLI_shm_lhnd_get(hnd), start_addr, 0x0);
if (*shm_addr_ptr == (void *) -1) {
rc = MPL_SHM_EINVAL;
}
}
fn_exit:
return rc;
}
static inline int MPL_shm_seg_create_attach_templ(
MPL_shm_hnd_t hnd, intptr_t seg_sz, char **shm_addr_ptr,
int offset, int flag)
{
HANDLE lhnd = INVALID_HANDLE_VALUE;
int rc = -1;
ULARGE_INTEGER seg_sz_large;
seg_sz_large.QuadPart = seg_sz;
if(!MPLI_shm_ghnd_is_valid(hnd)){
rc = MPLI_shm_ghnd_set_uniq(hnd);
}
if(flag & MPLI_SHM_FLAG_SHM_CREATE){
lhnd = CreateFileMapping(INVALID_HANDLE_VALUE, NULL,
PAGE_READWRITE, seg_sz_large.HighPart, seg_sz_large.LowPart,
MPLI_shm_ghnd_get_by_ref(hnd));
MPLI_shm_lhnd_set(hnd, lhnd);
}
else{
if(!MPLI_shm_lhnd_is_valid(hnd)){
/* Strangely OpenFileMapping() returns NULL on error! */
lhnd = OpenFileMapping(FILE_MAP_WRITE, FALSE,
MPLI_shm_ghnd_get_by_ref(hnd));
MPLI_shm_lhnd_set(hnd, lhnd);
}
}
if(flag & MPLI_SHM_FLAG_SHM_ATTACH){
*shm_addr_ptr = (char *)MapViewOfFile(MPLI_shm_lhnd_get(hnd),
FILE_MAP_WRITE, 0, offset, 0);
}
fn_exit:
return rc;
fn_fail:
goto fn_exit;
}
