int jlog_ctx_add_subscriber(jlog_ctx *ctx, const char *s, jlog_position whence) { jlog_id chkpt; jlog_ctx *tmpctx = NULL; jlog_file *jchkpt; ctx->last_error = JLOG_ERR_SUCCESS; jchkpt = __jlog_open_named_checkpoint(ctx, s, O_CREAT|O_EXCL); if(!jchkpt) { ctx->last_error = JLOG_ERR_SUBSCRIBER_EXISTS; ctx->last_errno = EEXIST; return -1; } jlog_file_close(jchkpt); if(whence == JLOG_BEGIN) { memset(&chkpt, 0, sizeof(chkpt)); jlog_ctx_first_log_id(ctx, &chkpt); if(__jlog_set_checkpoint(ctx, s, &chkpt) != 0) { ctx->last_error = JLOG_ERR_CHECKPOINT; ctx->last_errno = 0; return -1; } return 0; } if(whence == JLOG_END) { jlog_id start, finish; memset(&chkpt, 0, sizeof(chkpt)); if(__jlog_open_metastore(ctx) != 0) SYS_FAIL(JLOG_ERR_META_OPEN); if(__jlog_restore_metastore(ctx, 0)) SYS_FAIL(JLOG_ERR_META_OPEN); chkpt.log = ctx->storage.log; if(__jlog_set_checkpoint(ctx, s, &chkpt) != 0) SYS_FAIL(JLOG_ERR_CHECKPOINT); tmpctx = jlog_new(ctx->path); if(jlog_ctx_open_reader(tmpctx, s) < 0) goto finish; if(jlog_ctx_read_interval(tmpctx, &start, &finish) < 0) goto finish; jlog_ctx_close(tmpctx); tmpctx = NULL; if(__jlog_set_checkpoint(ctx, s, &finish) != 0) SYS_FAIL(JLOG_ERR_CHECKPOINT); return 0; } ctx->last_error = JLOG_ERR_NOT_SUPPORTED; finish: if(tmpctx) jlog_ctx_close(tmpctx); return -1; }
/* * returns -1 when the incoming checkpoint is out of range of the log * returns -2 if there was an error actually setting the checkpoint */ static int queue_log_add_checkpoint(fqd_queue_impl_data data, const char *name, const fq_msgid *id) { struct queue_jlog *d = (struct queue_jlog *)data; jlog_id jid = { .log = id->id.u32.p1, .marker = id->id.u32.p2 }; /* ensure the checkpoint makes sense */ jlog_id first = { .log = 0, .marker = 0 }; jlog_id last = { .log = 0, .marker = 0 }; jlog_ctx_first_log_id(d->reader, &first); jlog_ctx_last_log_id(d->reader, &last); if (! (jid.log >= first.log && jid.log <= last.log && jid.marker >= first.marker && jid.marker <= last.marker)) { return -1; } char **subs; int sub_count = jlog_ctx_list_subscribers(d->reader, &subs); int have_it = 0; for (int i = 0; i < sub_count; i++) { have_it += strcmp(subs[i], name) == 0 ? 1 : 0; } if (have_it == 0) { jlog_ctx_add_subscriber(d->reader, name, JLOG_BEGIN); } if (jlog_ctx_read_checkpoint(d->reader, &jid) == -1) { /* If we failed to checkpoint we are in a situation where the 'add_subscriber' call above put them at the beginning of the log so we have to remove the subscriber if we just added them However, if they already existed and had a previous good checkpoint, leave it alone */ if (have_it == 0) { jlog_ctx_remove_subscriber(d->reader, name); } return -2; } return 0; } /* * return -1 if the subscriber doesn't exist * return 0 on success */ static int queue_log_remove_checkpoint(fqd_queue_impl_data data, const char *name) { struct queue_jlog *d = (struct queue_jlog *)data; if (jlog_ctx_remove_subscriber(d->reader, name) == 0) { return -1; } return 0; } /* * return -1 if the subscriber doesn't exist * return -2 if we can't reset the checkpoint * return 0 on success */ static int queue_log_reset_to_checkpoint(fqd_queue_impl_data data, const char *name) { struct queue_jlog *d = (struct queue_jlog *)data; char **subs; int sub_count = jlog_ctx_list_subscribers(d->reader, &subs); int have_it = 0; for (int i = 0; i < sub_count; i++) { have_it += strcmp(subs[i], name) == 0 ? 1 : 0; } if (have_it == 0) { return -1; } jlog_id checkpoint; if (jlog_get_checkpoint(d->reader, name, &checkpoint) == -1) { return -2; } if (jlog_ctx_read_checkpoint(d->reader, &checkpoint) == -1) { return -2; } return 0; } static int write_sig(struct queue_jlog *d) { char sigfile[PATH_MAX]; int fd; snprintf(sigfile, sizeof(sigfile), "%s/.sig", d->qpath); fd = open(sigfile, O_CREAT|O_TRUNC|O_WRONLY, 0640); if(fd < 0) return -1; write(fd, d->uuid, 16); close(fd); return 0; } static int read_sig(struct queue_jlog *d, uuid_t out) { char sigfile[PATH_MAX]; int fd, rv; snprintf(sigfile, sizeof(sigfile), "%s/.sig", d->qpath); fd = open(sigfile, O_RDONLY); if(fd < 0) return -1; rv = read(fd, out, 16); close(fd); return (rv == 16) ? 0 : -1; } static fqd_queue_impl_data queue_jlog_setup(fq_rk *qname, uint32_t *count) { char qpath[PATH_MAX]; jlog_id chkpt; struct queue_jlog *d; d = calloc(1, sizeof(*d)); d->auto_chkpt = true; fqd_config_construct_queue_path(qpath, sizeof(qpath), qname); d->qpath = strdup(qpath); d->writer = jlog_new(d->qpath); jlog_ctx_set_pre_commit_buffer_size(d->writer, 1024 * 1024); jlog_ctx_set_multi_process(d->writer, 0); jlog_ctx_set_use_compression(d->writer, 1); if(jlog_ctx_open_writer(d->writer) != 0) { jlog_ctx_close(d->writer); d->writer = jlog_new(d->qpath); jlog_ctx_set_pre_commit_buffer_size(d->writer, 1024 * 1024); jlog_ctx_set_multi_process(d->writer, 0); jlog_ctx_set_use_compression(d->writer, 1); if(jlog_ctx_init(d->writer) != 0) { fq_debug(FQ_DEBUG_IO, "jlog init: %s\n", jlog_ctx_err_string(d->writer)); goto bail; } jlog_ctx_close(d->writer); d->writer = jlog_new(d->qpath); jlog_ctx_set_pre_commit_buffer_size(d->writer, 1024 * 1024); jlog_ctx_set_multi_process(d->writer, 0); jlog_ctx_set_use_compression(d->writer, 1); if(jlog_ctx_open_writer(d->writer) != 0) { fq_debug(FQ_DEBUG_IO, "jlog writer: %s\n", jlog_ctx_err_string(d->writer)); goto bail; } } /* 128MB journal chunks */ jlog_ctx_alter_journal_size(d->writer, 128 * 1024 * 1024); d->reader = jlog_new(d->qpath); if(jlog_get_checkpoint(d->reader, "fq", &chkpt) != 0) { if(jlog_ctx_add_subscriber(d->reader, "fq", JLOG_BEGIN) != 0) { fq_debug(FQ_DEBUG_IO, "jlog add sub: %s\n", jlog_ctx_err_string(d->reader)); goto bail; } } if(jlog_ctx_open_reader(d->reader, "fq") != 0) { fq_debug(FQ_DEBUG_IO, "jlog: %s\n", jlog_ctx_err_string(d->reader)); goto bail; } uuid_generate(d->uuid); write_sig(d); *count = d->count = jlog_ctx_read_interval(d->reader, &d->start, &d->finish); (void)qname; return d; bail: if(d->writer) jlog_ctx_close(d->writer); if(d->reader) jlog_ctx_close(d->reader); free(d->qpath); free(d); return NULL; }