src/cli/babeltrace2-query.c

   1 /*
   2  * SPDX-License-Identifier: MIT
   3  *
   4  * Copyright 2016-2019 EfficiOS Inc.
   5  */
   6
   7 #define BT_LOG_TAG "CLI/QUERY"
   8 #include "logging.h"
   9
  10 #include <babeltrace2/babeltrace.h>
  11
  12 #include "common/common.h"
  13
  14 #include "babeltrace2-query.h"
  15
  16 static
  17 void set_fail_reason(const char **fail_reason, const char *reason)
  18 {
  19         if (fail_reason) {
  20                 *fail_reason = reason;
  21         }
  22 }
  23
  24 bt_query_executor_query_status cli_query(const bt_component_class *comp_cls,
  25                 const char *obj, const bt_value *params,
  26                 bt_logging_level log_level, const bt_interrupter *interrupter,
  27                 const bt_value **user_result, const char **fail_reason)
  28 {
  29         const bt_value *result = NULL;
  30         bt_query_executor_query_status status;
  31         bt_query_executor *query_exec;
  32
  33         set_fail_reason(fail_reason, "unknown error");
  34         BT_ASSERT(user_result);
  35         query_exec = bt_query_executor_create(comp_cls, obj, params);
  36         if (!query_exec) {
  37                 BT_CLI_LOGE_APPEND_CAUSE("Cannot create a query executor.");
  38                 goto error;
  39         }
  40
  41         if (bt_query_executor_set_logging_level(query_exec, log_level) !=
  42                         BT_QUERY_EXECUTOR_SET_LOGGING_LEVEL_STATUS_OK) {
  43                 BT_CLI_LOGE_APPEND_CAUSE(
  44                         "Cannot set query executor's logging level: "
  45                         "log-level=%s",
  46                         bt_common_logging_level_string(log_level));
  47                 goto error;
  48         }
  49
  50         if (interrupter) {
  51                 if (bt_query_executor_add_interrupter(query_exec,
  52                                 interrupter) !=
  53                                 BT_QUERY_EXECUTOR_ADD_INTERRUPTER_STATUS_OK) {
  54                         BT_CLI_LOGE_APPEND_CAUSE(
  55                                 "Cannot add interrupter to query executor.");
  56                         goto error;
  57                 }
  58         }
  59
  60         while (true) {
  61                 status = bt_query_executor_query(query_exec, &result);
  62                 switch (status) {
  63                 case BT_QUERY_EXECUTOR_QUERY_STATUS_OK:
  64                         goto ok;
  65                 case BT_QUERY_EXECUTOR_QUERY_STATUS_AGAIN:
  66                 {
  67                         const uint64_t sleep_time_us = 100000;
  68
  69                         if (interrupter && bt_interrupter_is_set(interrupter)) {
  70                                 set_fail_reason(fail_reason, "interrupted by user");
  71                                 goto error;
  72                         }
  73
  74                         /* Wait 100 ms and retry */
  75                         BT_LOGD("Got BT_QUERY_EXECUTOR_QUERY_STATUS_AGAIN: sleeping: "
  76                                 "time-us=%" PRIu64, sleep_time_us);
  77
  78                         if (usleep(sleep_time_us)) {
  79                                 if (interrupter && bt_interrupter_is_set(interrupter)) {
  80                                         BT_CLI_LOGW_APPEND_CAUSE(
  81                                                 "Query was interrupted by user: "
  82                                                 "comp-cls-addr=%p, comp-cls-name=\"%s\", "
  83                                                 "query-obj=\"%s\"", comp_cls,
  84                                                 bt_component_class_get_name(comp_cls),
  85                                                 obj);
  86                                         set_fail_reason(fail_reason,
  87                                                 "interrupted by user");
  88                                         goto error;
  89                                 }
  90                         }
  91
  92                         continue;
  93                 }
  94                 case BT_QUERY_EXECUTOR_QUERY_STATUS_ERROR:
  95                         if (interrupter && bt_interrupter_is_set(interrupter)) {
  96                                 set_fail_reason(fail_reason, "interrupted by user");
  97                                 goto error;
  98                         }
  99
 100                         goto error;
 101                 case BT_QUERY_EXECUTOR_QUERY_STATUS_UNKNOWN_OBJECT:
 102                         set_fail_reason(fail_reason, "unknown query object");
 103                         goto end;
 104                 case BT_QUERY_EXECUTOR_QUERY_STATUS_MEMORY_ERROR:
 105                         set_fail_reason(fail_reason, "not enough memory");
 106                         goto error;
 107                 default:
 108                         BT_LOGF("Unknown query status: status=%s",
 109                                 bt_common_func_status_string(status));
 110                         bt_common_abort();
 111                 }
 112         }
 113
 114 ok:
 115         *user_result = result;
 116         result = NULL;
 117         goto end;
 118
 119 error:
 120         status = BT_QUERY_EXECUTOR_QUERY_STATUS_ERROR;
 121
 122 end:
 123         bt_query_executor_put_ref(query_exec);
 124         bt_value_put_ref(result);
 125         return status;
 126 }