lh | 9ed821d | 2023-04-07 01:36:19 -0700 | [diff] [blame] | 1 | /* |
| 2 | * mq_open.c - open a message queue. |
| 3 | */ |
| 4 | |
| 5 | #include <errno.h> |
| 6 | #include <stdarg.h> |
| 7 | #include <stddef.h> |
| 8 | #include <sys/syscall.h> |
| 9 | |
| 10 | #include <mqueue.h> |
| 11 | |
| 12 | #ifdef __NR_mq_open |
| 13 | |
| 14 | #define __NR___syscall_mq_open __NR_mq_open |
| 15 | static __inline__ _syscall4(int, __syscall_mq_open, const char *, name, |
| 16 | int, oflag, __kernel_mode_t, mode, void *, attr); |
| 17 | /* |
| 18 | * Establish connection between a process and a message queue and |
| 19 | * return message queue descriptor or (mqd_t) -1 on error. |
| 20 | * oflag determines the type of access used. If O_CREAT is on oflag, the |
| 21 | * third argument is taken as a `mode_t', the mode of the created |
| 22 | * message queue, and the fourth argument is taken as `struct mq_attr *', |
| 23 | * pointer to message queue attributes. |
| 24 | * If the fourth argument is NULL, default attributes are used. |
| 25 | */ |
| 26 | mqd_t mq_open(const char *name, int oflag, ...) |
| 27 | { |
| 28 | mode_t mode; |
| 29 | struct mq_attr *attr; |
| 30 | |
| 31 | if (name[0] != '/') { |
| 32 | __set_errno(EINVAL); |
| 33 | return -1; |
| 34 | } |
| 35 | |
| 36 | mode = 0; |
| 37 | attr = NULL; |
| 38 | |
| 39 | if (oflag & O_CREAT) { |
| 40 | va_list ap; |
| 41 | |
| 42 | va_start(ap, oflag); |
| 43 | mode = va_arg(ap, mode_t); |
| 44 | attr = va_arg(ap, struct mq_attr *); |
| 45 | |
| 46 | va_end(ap); |
| 47 | } |
| 48 | |
| 49 | return __syscall_mq_open(name + 1, oflag, mode, attr); |
| 50 | } |
| 51 | |
| 52 | #endif |