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path: root/newlib/libc/sys/linux/mq_open.c
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Diffstat (limited to 'newlib/libc/sys/linux/mq_open.c')
-rw-r--r--newlib/libc/sys/linux/mq_open.c346
1 files changed, 0 insertions, 346 deletions
diff --git a/newlib/libc/sys/linux/mq_open.c b/newlib/libc/sys/linux/mq_open.c
deleted file mode 100644
index 9b72e9073..000000000
--- a/newlib/libc/sys/linux/mq_open.c
+++ /dev/null
@@ -1,346 +0,0 @@
-/* Copyright 2002, Red Hat Inc. */
-
-#include <mqueue.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <errno.h>
-#include <sys/stat.h>
-#include <sys/mman.h>
-#include <sys/ipc.h>
-#include <sys/sem.h>
-#include <string.h>
-#include <stdlib.h>
-#include <time.h>
-#include <stdarg.h>
-#include <machine/weakalias.h>
-#define _LIBC 1
-#include <sys/lock.h>
-#undef _LIBC
-
-#include "mqlocal.h"
-
-#define NHASH 32 /* Num of hash lists, must be a power of 2 */
-#define LOCHASH(i) ((i)&(NHASH-1))
-
-static long mq_index; /* Index of next entry */
-static struct libc_mq *mq_hash[NHASH]; /* Hash list heads for mqopen_infos */
-
-__LOCK_INIT(static, mq_hash_lock);
-
-mqd_t
-mq_open (const char *name, int oflag, ...)
-{
- MSG *wrbuf = NULL;
- MSG *rdbuf = NULL;
- int msgqid = -1;
- int rc = -1;
- int fd = -1;
- int semid = -1;
- int created = 0;
- key_t key = (key_t)-1;
- struct mq_attr *attr = (struct mq_attr *)MAP_FAILED;
- struct sembuf sb = {0, 0, 0};
- mode_t mode = 0;
- int size;
- int i, index, saved_errno;
- char *real_name;
- char *ptr;
- struct mq_attr *user_attr = NULL;
- struct libc_mq *info;
- union semun arg;
-
- /* ignore opening slash if present */
- if (*name == '/')
- ++name;
- size = strlen(name);
-
- if ((real_name = (char *)malloc (size + sizeof(MSGQ_PREFIX))) == NULL ||
- (info = (struct libc_mq *)malloc (sizeof(struct libc_mq))) == NULL)
- {
- errno = ENOSPC;
- if (real_name)
- free (real_name);
- return (mqd_t)-1;
- }
-
- /* use given name to create shared memory file name - we convert any
- slashes to underscores so we don't have to create directories */
- memcpy (real_name, MSGQ_PREFIX, sizeof(MSGQ_PREFIX) - 1);
- memcpy (real_name + sizeof(MSGQ_PREFIX) - 1, name, size + 1);
- ptr = real_name + sizeof(MSGQ_PREFIX) - 1;
- for (i = 0; i < size; ++i)
- {
- if (*ptr == '/')
- *ptr = '_';
- ++ptr;
- }
-
- /* open shared memory file based on msg queue open flags and then use memory
- file to create a unique key to use for semaphores, etc.. */
- if (oflag & O_CREAT)
- {
- va_list list;
- va_start (list, oflag);
-
- saved_errno = errno;
- mode = (mode_t)va_arg (list, int);
- user_attr = va_arg(list,struct mq_attr *);
- va_end (list);
-
- /* attempt to open the shared memory file for exclusive create so we know
- whether we are the owners or not */
- fd = open (real_name, O_RDWR | O_CREAT | O_EXCL, mode);
- if (fd < 0 && (oflag & O_EXCL))
- {
- /* we failed and the user wanted exclusive create */
- free (real_name);
- free (info);
- return (mqd_t)-1;
- }
- errno = saved_errno;
- /* check if we created the file or not */
- if (fd >= 0)
- created = 1;
- }
-
- if (fd < 0)
- fd = open (real_name, O_RDWR, 0);
-
- if (fd >= 0)
- key = ftok(real_name, 255);
-
- if (key != (key_t)-1)
- /* memory map the shared memory file so we have a global shared data area to use */
- attr = (struct mq_attr *)mmap (0, sizeof(struct mq_attr), PROT_READ | PROT_WRITE,
- MAP_SHARED, fd, 0);
-
- if (attr != (struct mq_attr *)MAP_FAILED)
- {
- /* we need semaphores to prevent multi-process race conditions on the
- shared storage which contains a shared structure. The following
- are the ones we need.
-
- 0 = open semaphore
- 1 = number of opens
- 2 = number of writes left until queue is full
- 3 = number of reads available in queue
- 4 = notify semaphore
- 5 = number of readers */
- arg.val = 0;
- /* make sure the creator of the shared memory file also is the creator of the
- semaphores...this will ensure that it also creates the message queue */
- if (created)
- {
- saved_errno = errno;
- semid = semget (key, 6, IPC_CREAT | IPC_EXCL | mode);
- errno = saved_errno;
- /* now that we have created the semaphore, we should initialize it */
- if (semid != -1)
- semctl (semid, 0, SETVAL, arg);
- }
- else
- {
- /* if we didn't create the shared memory file but have gotten to here, we want
- to ensure we haven't gotten ahead of the creator temporarily so we will
- loop until the semaphore exists. This ensures that the creator will be the
- one to create the message queue with the correct mode and we will be blocked
- by the open semaphore 0. We impose a time limit to ensure something terrible
- hasn't gone wrong. */
- struct timespec tms;
- int i;
-
- tms.tv_sec = 0;
- tms.tv_nsec = 10000; /* 10 microseconds */
- for (i = 0; i < 100; ++i)
- {
- if ((semid = semget (key, 6, 0)) != -1)
- break;
- /* sleep in case we our a higher priority process */
- nanosleep (&tms, NULL);
- }
- }
- }
-
- if (semid != -1)
- {
- /* acquire main open semaphore if we didn't create it */
- if (!created)
- {
- sb.sem_op = -1;
- rc = semop (semid, &sb, 1);
- }
- else
- rc = 0; /* need this to continue below */
- }
-
- if (rc == 0)
- {
- if (created)
- {
- /* the creator must get here first so the message queue will be created */
- msgqid = msgget (key, IPC_CREAT | mode);
- if (msgqid >= 0)
- {
- /* we have created the message queue so check and set the attributes */
- if ((wrbuf = (MSG *)malloc (user_attr->mq_msgsize + sizeof(int))) == NULL ||
- (rdbuf = (MSG *)malloc (user_attr->mq_msgsize + sizeof(int))) == NULL ||
- user_attr == NULL || user_attr->mq_msgsize <= 0 || user_attr->mq_maxmsg <= 0)
- {
- /* we're out of space and we created the message queue so we should
- try to remove it */
- msgctl (msgqid, IPC_RMID, NULL);
- msgqid = -1; /* allow clean up to occur below */
- if (wrbuf && rdbuf)
- errno = EINVAL;
- else
- errno = ENOSPC;
- }
- else /* valid attributes */
- {
- write (fd, user_attr, sizeof(struct mq_attr));
- attr->mq_curmsgs = 0;
- attr->mq_flags = oflag & O_NONBLOCK;
- arg.val = 0;
- semctl (semid, 1, SETVAL, arg); /* number of opens starts at 0 */
- semctl (semid, 3, SETVAL, arg); /* number of reads available starts at 0 */
- semctl (semid, 5, SETVAL, arg); /* number of readers starts at 0 */
- arg.val = 1;
- semctl (semid, 4, SETVAL, arg); /* notify semaphore */
- arg.val = user_attr->mq_maxmsg;
- semctl (semid, 2, SETVAL, arg); /* number of writes left starts at mq_maxmsg */
- }
- }
- }
- else /* just open it */
- {
- msgqid = msgget (key, 0);
- wrbuf = (MSG *)malloc (attr->mq_msgsize + sizeof(int));
- rdbuf = (MSG *)malloc (attr->mq_msgsize + sizeof(int));
- }
-
- /* release semaphore acquired earlier */
- sb.sem_op = 1;
- semop (semid, &sb, 1);
- }
-
- /* if we get here and we haven't got a message queue id, then we need to clean up
- our mess and return failure */
- if (msgqid < 0)
- {
- if (fd >= 0)
- close (fd);
- if (attr != (struct mq_attr *)MAP_FAILED)
- munmap (attr, sizeof(struct mq_attr));
- if (created)
- {
- unlink (real_name);
- if (semid != -1)
- semctl (semid, 0, IPC_RMID);
- }
- free (real_name);
- free (info);
- if (wrbuf)
- free (wrbuf);
- if (rdbuf)
- free (rdbuf);
- return (mqd_t)-1;
- }
-
- /* we are successful so register the message queue */
-
- /* up the count of msg queue opens */
- sb.sem_op = 1;
- sb.sem_num = 1;
- semop (semid, &sb, 1);
-
- /* success, translate into index into mq_info array */
- __lock_acquire(mq_hash_lock);
- index = mq_index++;
- info->index = index;
- info->msgqid = msgqid;
- info->name = real_name;
- info->semid = semid;
- info->fd = fd;
- info->oflag = oflag;
- info->wrbuf = wrbuf;
- info->rdbuf = rdbuf;
- info->cleanup_notify = NULL;
- info->next = mq_hash[LOCHASH(index)];
- info->attr = attr;
- mq_hash[LOCHASH(index)] = info;
- __lock_release(mq_hash_lock);
-
- return (mqd_t)index;
-}
-
-struct libc_mq *
-__find_mq (mqd_t mq)
-{
- struct libc_mq *ptr;
-
- __lock_acquire(mq_hash_lock);
-
- ptr = mq_hash[LOCHASH((int)mq)];
-
- while (ptr)
- {
- if (ptr->index == (int)mq)
- break;
- ptr = ptr->next;
- }
-
- __lock_release(mq_hash_lock);
-
- return ptr;
-}
-
-void
-__cleanup_mq (mqd_t mq)
-{
- struct libc_mq *ptr;
- struct libc_mq *prev;
- int semid;
- struct sembuf sb = {0, 0, 0};
-
- __lock_acquire(mq_hash_lock);
-
- ptr = mq_hash[LOCHASH((int)mq)];
- prev = NULL;
-
- while (ptr)
- {
- if (ptr->index == (int)mq)
- break;
- prev = ptr;
- ptr = ptr->next;
- }
-
- if (ptr != NULL)
- {
- if (ptr->cleanup_notify != NULL)
- ptr->cleanup_notify (ptr);
- if (prev != NULL)
- prev->next = ptr->next;
- else
- mq_hash[LOCHASH((int)mq)] = NULL;
- munmap (ptr->attr, sizeof(struct mq_attr));
- close (ptr->fd);
- free (ptr->name);
- free (ptr->wrbuf);
- free (ptr->rdbuf);
- semid = ptr->semid;
- free (ptr);
- /* lower the count of msg queue opens */
- sb.sem_op = -1;
- sb.sem_num = 1;
- sb.sem_flg = IPC_NOWAIT;
- semop (semid, &sb, 1);
- }
-
- __lock_release(mq_hash_lock);
-}
-
-
-
-
-
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