/** \brief Get a POSIX shared object identifier for a shared
* memory segment by name
*
* \b os_posix_getShmObjName tries to find a POSIX shared object
* name for a named shared memory segment by calling \b os_posix_findKeyFile.
*
* If the shared object identifier is not found, one is created by
* calling \b mkstemp. And an related key file is produced containing
* the name, the map address and the size. The name of the shared object
* identifier is returned.
*
* If the shared object identifier is found, it's name is returned.
*
* The name of the shared object is equal to the path of the related
* key file except for the leading "/tmp/"
*/
static char *
os_posix_getShmObjName (
const char *name,
void *map_address,
os_address size,
const int id)
{
int key_file_fd;
char *key_file_name;
unsigned int name_len;
char *db_file_name;
char buffer[50];
key_file_name = os_posix_findKeyFileByIdAndName (id,name);
if (key_file_name == NULL) {
if (map_address != NULL) {
name_len = strlen (os_posix_key_file_prefix) + 1;
key_file_name = os_malloc (name_len);
if (key_file_name != NULL) {
snprintf (key_file_name, name_len, "%s", os_posix_key_file_prefix);
key_file_fd = os_mkstemp (key_file_name);
write (key_file_fd, name, strlen(name) + 1);
write (key_file_fd, "\n", 1);
snprintf (buffer, sizeof (buffer), PA_ADDRFMT"\n", (PA_ADDRCAST)map_address);
write (key_file_fd, buffer, strlen(buffer));
snprintf (buffer, sizeof (buffer), PA_ADDRFMT"\n", (PA_ADDRCAST)size);
write (key_file_fd, buffer, strlen(buffer));
snprintf (buffer, sizeof (buffer), "POSIX-SMO\n");
write (key_file_fd, buffer, strlen(buffer));
snprintf (buffer, sizeof (buffer), "%d\n", getpid());
write (key_file_fd, buffer, strlen(buffer));
snprintf(buffer, sizeof (buffer), "%d\n", id);
write(key_file_fd, buffer, strlen(buffer));
close (key_file_fd);
}
}
}
if (key_file_name != NULL) {
db_file_name = os_malloc(strlen(key_file_name));
if (db_file_name != NULL) {
os_strcpy (db_file_name, "/");
os_strcat (db_file_name, &key_file_name[4]);
}
os_free (key_file_name);
} else {
db_file_name = NULL;
}
return db_file_name;
}
/*
* util_tmpfile -- create a temporary file
*/
int
util_tmpfile(const char *dir, const char *templ)
{
LOG(3, "dir \"%s\" template \"%s\"", dir, templ);
int oerrno;
int fd = -1;
char fullname[MAX_PATH];
int ret = _snprintf(fullname, MAX_PATH, "%s%s", dir, templ);
if (ret < 0 || ret >= MAX_PATH) {
ERR("!snprintf");
goto err;
}
LOG(4, "fullname \"%s\"", fullname);
/*
* XXX - block signals and modify file creation mask for the time
* of mkstmep() execution. Restore previous settings once the file
* is created.
*/
fd = os_mkstemp(fullname);
if (fd < 0) {
ERR("!os_mkstemp");
goto err;
}
/*
* There is no point to use unlink() here. First, because it does not
* work on open files. Second, because the file is created with
* O_TEMPORARY flag, and it looks like such temp files cannot be open
* from another process, even though they are visible on
* the filesystem.
*/
return fd;
err:
oerrno = errno;
if (fd != -1)
(void) os_close(fd);
errno = oerrno;
return -1;
}
