+ /*
+ * We have either a filter or some exclusions, so we need to set up
+ * a variable-length memory block from where to send the data
+ */
+
+ /* Parse filter expression */
+ if (filter_expression != NULL) {
+
+ /*
+ * casting const to non-const, as the underlying function will
+ * use it in read-only mode.
+ */
+ fmem = lttng_fmemopen((void *) filter_expression,
+ strlen(filter_expression), "r");
+ if (!fmem) {
+ fprintf(stderr, "Error opening memory as stream\n");
+ return -LTTNG_ERR_FILTER_NOMEM;
+ }
+ ctx = filter_parser_ctx_alloc(fmem);
+ if (!ctx) {
+ fprintf(stderr, "Error allocating parser\n");
+ ret = -LTTNG_ERR_FILTER_NOMEM;
+ goto filter_alloc_error;
+ }
+ ret = filter_parser_ctx_append_ast(ctx);
+ if (ret) {
+ fprintf(stderr, "Parse error\n");
+ ret = -LTTNG_ERR_FILTER_INVAL;
+ goto parse_error;
+ }
+ ret = filter_visitor_set_parent(ctx);
+ if (ret) {
+ fprintf(stderr, "Set parent error\n");
+ ret = -LTTNG_ERR_FILTER_INVAL;
+ goto parse_error;
+ }
+ if (print_xml) {
+ ret = filter_visitor_print_xml(ctx, stdout, 0);
+ if (ret) {
+ fflush(stdout);
+ fprintf(stderr, "XML print error\n");
+ ret = -LTTNG_ERR_FILTER_INVAL;
+ goto parse_error;
+ }
+ }
+
+ dbg_printf("Generating IR... ");
+ fflush(stdout);
+ ret = filter_visitor_ir_generate(ctx);
+ if (ret) {
+ fprintf(stderr, "Generate IR error\n");
+ ret = -LTTNG_ERR_FILTER_INVAL;
+ goto parse_error;
+ }
+ dbg_printf("done\n");
+
+ dbg_printf("Validating IR... ");
+ fflush(stdout);
+ ret = filter_visitor_ir_check_binary_op_nesting(ctx);
+ if (ret) {
+ ret = -LTTNG_ERR_FILTER_INVAL;
+ goto parse_error;
+ }
+ dbg_printf("done\n");
+
+ dbg_printf("Generating bytecode... ");
+ fflush(stdout);
+ ret = filter_visitor_bytecode_generate(ctx);
+ if (ret) {
+ fprintf(stderr, "Generate bytecode error\n");
+ ret = -LTTNG_ERR_FILTER_INVAL;
+ goto parse_error;
+ }
+ dbg_printf("done\n");
+ dbg_printf("Size of bytecode generated: %u bytes.\n",
+ bytecode_get_len(&ctx->bytecode->b));
+
+ lsm.u.enable.bytecode_len = sizeof(ctx->bytecode->b)
+ + bytecode_get_len(&ctx->bytecode->b);
+ lsm.u.enable.expression_len = strlen(filter_expression) + 1;
+ }
+
+ varlen_data = zmalloc(lsm.u.enable.bytecode_len
+ + lsm.u.enable.expression_len
+ + LTTNG_SYMBOL_NAME_LEN * exclusion_count);
+ if (!varlen_data) {
+ ret = -LTTNG_ERR_EXCLUSION_NOMEM;
+ goto varlen_alloc_error;
+ }
+ /* Put exclusion names first in the data */
+ while (exclusion_count--) {
+ strncpy(varlen_data + LTTNG_SYMBOL_NAME_LEN * exclusion_count,
+ *(exclusion_list + exclusion_count),
+ LTTNG_SYMBOL_NAME_LEN);
+ }
+ /* Add filter expression next */
+ if (lsm.u.enable.expression_len != 0) {
+ memcpy(varlen_data
+ + LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count,
+ filter_expression,
+ lsm.u.enable.expression_len);
+ }
+ /* Add filter bytecode next */
+ if (lsm.u.enable.bytecode_len != 0) {
+ memcpy(varlen_data
+ + LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count
+ + lsm.u.enable.expression_len,
+ &ctx->bytecode->b,
+ lsm.u.enable.bytecode_len);
+ }
+
+ ret = lttng_ctl_ask_sessiond_varlen(&lsm, varlen_data,
+ (LTTNG_SYMBOL_NAME_LEN * lsm.u.enable.exclusion_count) +
+ lsm.u.enable.bytecode_len + lsm.u.enable.expression_len,
+ NULL);
+ free(varlen_data);
+
+varlen_alloc_error:
+ if (filter_expression) {
+ filter_bytecode_free(ctx);
+ filter_ir_free(ctx);
+ filter_parser_ctx_free(ctx);
+ if (fclose(fmem) != 0) {
+ perror("fclose");
+ }