qb_ringbuffer_t * qb_rb_open(const char *name, size_t size, uint32_t flags, size_t shared_user_data_size) { struct qb_ringbuffer_s *rb; size_t real_size; size_t shared_size; char path[PATH_MAX]; int32_t fd_hdr; int32_t fd_data; uint32_t file_flags = O_RDWR; char filename[PATH_MAX]; int32_t error = 0; void *shm_addr; long page_size = sysconf(_SC_PAGESIZE); #ifdef QB_FORCE_SHM_ALIGN page_size = QB_MAX(page_size, 16 * 1024); #endif /* QB_FORCE_SHM_ALIGN */ real_size = QB_ROUNDUP(size, page_size); shared_size = sizeof(struct qb_ringbuffer_shared_s) + shared_user_data_size; if (flags & QB_RB_FLAG_CREATE) { file_flags |= O_CREAT | O_TRUNC; } rb = calloc(1, sizeof(struct qb_ringbuffer_s)); if (rb == NULL) { return NULL; } /* * Create a shared_hdr memory segment for the header. */ snprintf(filename, PATH_MAX, "qb-%s-header", name); fd_hdr = qb_sys_mmap_file_open(path, filename, shared_size, file_flags); if (fd_hdr < 0) { error = fd_hdr; qb_util_log(LOG_ERR, "couldn't create file for mmap"); goto cleanup_hdr; } rb->shared_hdr = mmap(0, shared_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd_hdr, 0); if (rb->shared_hdr == MAP_FAILED) { error = -errno; qb_util_log(LOG_ERR, "couldn't create mmap for header"); goto cleanup_hdr; } rb->flags = flags; /* * create the semaphore */ if (flags & QB_RB_FLAG_CREATE) { rb->shared_data = NULL; /* rb->shared_hdr->word_size tracks data by ints and not bytes/chars. */ rb->shared_hdr->word_size = real_size / sizeof(uint32_t); rb->shared_hdr->write_pt = 0; rb->shared_hdr->read_pt = 0; (void)strlcpy(rb->shared_hdr->hdr_path, path, PATH_MAX); } error = qb_rb_sem_create(rb, flags); if (error < 0) { qb_util_perror(LOG_ERR, "couldn't get a semaphore"); goto cleanup_hdr; } /* Create the shared_data memory segment for the actual ringbuffer. * They have to be separate. */ if (flags & QB_RB_FLAG_CREATE) { snprintf(filename, PATH_MAX, "qb-%s-data", name); fd_data = qb_sys_mmap_file_open(path, filename, real_size, file_flags); (void)strlcpy(rb->shared_hdr->data_path, path, PATH_MAX); } else { fd_data = qb_sys_mmap_file_open(path, rb->shared_hdr->data_path, real_size, file_flags); } if (fd_data < 0) { error = fd_data; qb_util_log(LOG_ERR, "couldn't create file for mmap"); goto cleanup_hdr; } qb_util_log(LOG_DEBUG, "shm size:%zd; real_size:%zd; rb->word_size:%d", size, real_size, rb->shared_hdr->word_size); error = qb_sys_circular_mmap(fd_data, &shm_addr, real_size); rb->shared_data = shm_addr; if (error != 0) { qb_util_log(LOG_ERR, "couldn't create circular mmap on %s", rb->shared_hdr->data_path); goto cleanup_data; } if (flags & QB_RB_FLAG_CREATE) { memset(rb->shared_data, 0, real_size); rb->shared_data[rb->shared_hdr->word_size] = 5; rb->shared_hdr->ref_count = 1; } else { qb_atomic_int_inc(&rb->shared_hdr->ref_count); } close(fd_hdr); close(fd_data); return rb; cleanup_data: close(fd_data); if (flags & QB_RB_FLAG_CREATE) { unlink(rb->shared_hdr->data_path); } cleanup_hdr: if (fd_hdr >= 0) { close(fd_hdr); } if (rb && (flags & QB_RB_FLAG_CREATE)) { unlink(rb->shared_hdr->hdr_path); (void)rb->sem_destroy_fn(rb); } if (rb && (rb->shared_hdr != MAP_FAILED && rb->shared_hdr != NULL)) { munmap(rb->shared_hdr, sizeof(struct qb_ringbuffer_shared_s)); } free(rb); errno = -error; return NULL; }
qb_ringbuffer_t * qb_rb_open_2(const char *name, size_t size, uint32_t flags, size_t shared_user_data_size, struct qb_rb_notifier *notifiers) { struct qb_ringbuffer_s *rb; size_t real_size; size_t shared_size; char path[PATH_MAX]; int32_t fd_hdr; int32_t fd_data; uint32_t file_flags = O_RDWR; char filename[PATH_MAX]; int32_t error = 0; void *shm_addr; long page_size = sysconf(_SC_PAGESIZE); #ifdef QB_ARCH_HPPA page_size = QB_MAX(page_size, 0x00400000); /* align to page colour */ #elif defined(QB_FORCE_SHM_ALIGN) page_size = QB_MAX(page_size, 16 * 1024); #endif /* QB_FORCE_SHM_ALIGN */ /* The user of this api expects the 'size' parameter passed into this function * to be reflective of the max size single write we can do to the * ringbuffer. This means we have to add both the 'margin' space used * to calculate if there is enough space for a new chunk as well as the '+1' that * prevents overlap of the read/write pointers */ size += QB_RB_CHUNK_MARGIN + 1; real_size = QB_ROUNDUP(size, page_size); shared_size = sizeof(struct qb_ringbuffer_shared_s) + shared_user_data_size; if (flags & QB_RB_FLAG_CREATE) { file_flags |= O_CREAT | O_TRUNC; } rb = calloc(1, sizeof(struct qb_ringbuffer_s)); if (rb == NULL) { return NULL; } /* * Create a shared_hdr memory segment for the header. */ snprintf(filename, PATH_MAX, "qb-%s-header", name); fd_hdr = qb_sys_mmap_file_open(path, filename, shared_size, file_flags); if (fd_hdr < 0) { error = fd_hdr; qb_util_log(LOG_ERR, "couldn't create file for mmap"); goto cleanup_hdr; } rb->shared_hdr = mmap(0, shared_size, PROT_READ | PROT_WRITE, MAP_SHARED, fd_hdr, 0); if (rb->shared_hdr == MAP_FAILED) { error = -errno; qb_util_log(LOG_ERR, "couldn't create mmap for header"); goto cleanup_hdr; } qb_atomic_init(); rb->flags = flags; /* * create the semaphore */ if (flags & QB_RB_FLAG_CREATE) { rb->shared_data = NULL; /* rb->shared_hdr->word_size tracks data by ints and not bytes/chars. */ rb->shared_hdr->word_size = real_size / sizeof(uint32_t); rb->shared_hdr->write_pt = 0; rb->shared_hdr->read_pt = 0; (void)strlcpy(rb->shared_hdr->hdr_path, path, PATH_MAX); } if (notifiers && notifiers->post_fn) { error = 0; memcpy(&rb->notifier, notifiers, sizeof(struct qb_rb_notifier)); } else { error = qb_rb_sem_create(rb, flags); } if (error < 0) { errno = -error; qb_util_perror(LOG_ERR, "couldn't create a semaphore"); goto cleanup_hdr; } /* Create the shared_data memory segment for the actual ringbuffer. * They have to be separate. */ if (flags & QB_RB_FLAG_CREATE) { snprintf(filename, PATH_MAX, "qb-%s-data", name); fd_data = qb_sys_mmap_file_open(path, filename, real_size, file_flags); (void)strlcpy(rb->shared_hdr->data_path, path, PATH_MAX); } else { fd_data = qb_sys_mmap_file_open(path, rb->shared_hdr->data_path, real_size, file_flags); } if (fd_data < 0) { error = fd_data; qb_util_log(LOG_ERR, "couldn't create file for mmap"); goto cleanup_hdr; } qb_util_log(LOG_DEBUG, "shm size:%ld; real_size:%ld; rb->word_size:%d", size, real_size, rb->shared_hdr->word_size); /* this function closes fd_data */ error = qb_sys_circular_mmap(fd_data, &shm_addr, real_size); rb->shared_data = shm_addr; if (error != 0) { qb_util_log(LOG_ERR, "couldn't create circular mmap on %s", rb->shared_hdr->data_path); goto cleanup_data; } if (flags & QB_RB_FLAG_CREATE) { memset(rb->shared_data, 0, real_size); rb->shared_data[rb->shared_hdr->word_size] = 5; rb->shared_hdr->ref_count = 1; } else { qb_atomic_int_inc(&rb->shared_hdr->ref_count); } close(fd_hdr); return rb; cleanup_data: if (flags & QB_RB_FLAG_CREATE) { unlink(rb->shared_hdr->data_path); } cleanup_hdr: if (fd_hdr >= 0) { close(fd_hdr); } if (rb && (flags & QB_RB_FLAG_CREATE)) { unlink(rb->shared_hdr->hdr_path); if (rb->notifier.destroy_fn) { (void)rb->notifier.destroy_fn(rb->notifier.instance); } } if (rb && (rb->shared_hdr != MAP_FAILED && rb->shared_hdr != NULL)) { munmap(rb->shared_hdr, sizeof(struct qb_ringbuffer_shared_s)); } free(rb); errno = -error; return NULL; }