|
Tor 0.4.9.0-alpha-dev
|
Track status and retry schedule of a downloadable object. More...
#include "core/or/or.h"#include "app/config/config.h"#include "feature/client/entrynodes.h"#include "feature/dirclient/dlstatus.h"#include "feature/nodelist/networkstatus.h"#include "feature/relay/routermode.h"#include "lib/crypt_ops/crypto_rand.h"#include "feature/dirclient/download_status_st.h"Go to the source code of this file.
Functions | |
| STATIC int | find_dl_min_delay (const download_status_t *dls, const or_options_t *options) |
| STATIC void | next_random_exponential_delay_range (int *low_bound_out, int *high_bound_out, int delay, int base_delay) |
| STATIC int | next_random_exponential_delay (int delay, int base_delay) |
| STATIC int | download_status_schedule_get_delay (download_status_t *dls, int min_delay, time_t now) |
| static void | download_status_log_helper (const char *item, int was_schedule_incremented, const char *increment_action, const char *not_incremented_response, uint8_t dls_n_download_increments, int increment, time_t dls_next_attempt_at, time_t now) |
| time_t | download_status_increment_failure (download_status_t *dls, int status_code, const char *item, int server, time_t now) |
| time_t | download_status_increment_attempt (download_status_t *dls, const char *item, time_t now) |
| static time_t | download_status_get_initial_delay_from_now (const download_status_t *dls) |
| void | download_status_reset (download_status_t *dls) |
| int | download_status_is_ready (download_status_t *dls, time_t now) |
| void | download_status_mark_impossible (download_status_t *dl) |
| int | download_status_get_n_failures (const download_status_t *dls) |
| int | download_status_get_n_attempts (const download_status_t *dls) |
| time_t | download_status_get_next_attempt_at (const download_status_t *dls) |
Track status and retry schedule of a downloadable object.
Definition in file dlstatus.c.
| #define DLSTATUS_PRIVATE |
Definition at line 11 of file dlstatus.c.
|
static |
Definition at line 344 of file dlstatus.c.
| int download_status_get_n_attempts | ( | const download_status_t * | dls | ) |
Return the number of attempts to download dls since the last success (if any). This can differ from download_status_get_n_failures() due to outstanding concurrent attempts.
Definition at line 410 of file dlstatus.c.
| int download_status_get_n_failures | ( | const download_status_t * | dls | ) |
Return the number of failures on dls since the last success (if any).
Definition at line 401 of file dlstatus.c.
Referenced by authority_cert_dl_looks_uncertain().
| time_t download_status_get_next_attempt_at | ( | const download_status_t * | dls | ) |
Return the next time to attempt to download dls.
Definition at line 417 of file dlstatus.c.
Referenced by download_status_is_ready().
| time_t download_status_increment_attempt | ( | download_status_t * | dls, |
| const char * | item, | ||
| time_t | now | ||
| ) |
Determine when the next download attempt should be made when using an attempt-based (potentially concurrent) download schedule. Called when an attempt to download dls is being initiated. Increment the attempt count and set dls->next_attempt_at to an appropriate time in the future and return it. If dls->increment_on is DL_SCHED_INCREMENT_FAILURE, don't increment the attempts, and return a time in the far future (to avoid launching a concurrent attempt).
Definition at line 308 of file dlstatus.c.
| time_t download_status_increment_failure | ( | download_status_t * | dls, |
| int | status_code, | ||
| const char * | item, | ||
| int | server, | ||
| time_t | now | ||
| ) |
Determine when a failed download attempt should be retried. Called when an attempt to download dls has failed with HTTP status status_code. Increment the failure count (if the code indicates a real failure, or if we're a server) and set dls->next_attempt_at to an appropriate time in the future and return it. If dls->increment_on is DL_SCHED_INCREMENT_ATTEMPT, increment the failure count, and return a time in the far future for the next attempt (to avoid an immediate retry).
Definition at line 249 of file dlstatus.c.
| int download_status_is_ready | ( | download_status_t * | dls, |
| time_t | now | ||
| ) |
Return true iff, as of now, the resource tracked by dls is ready to get its download reattempted.
Definition at line 380 of file dlstatus.c.
Referenced by download_status_is_ready_by_sk_in_cl(), and fetch_bridge_descriptors().
|
static |
Definition at line 216 of file dlstatus.c.
| void download_status_mark_impossible | ( | download_status_t * | dl | ) |
Mark dl as never downloadable.
Definition at line 392 of file dlstatus.c.
Referenced by fetch_bridge_descriptors(), and launch_direct_bridge_descriptor_fetch().
| void download_status_reset | ( | download_status_t * | dls | ) |
Reset dls so that it will be considered downloadable immediately, and/or to show that we don't need it anymore.
Must be called to initialise a download schedule, otherwise the zeroth item in the schedule will never be used.
(We find the zeroth element of the download schedule, and set next_attempt_at to be the appropriate offset from 'now'. In most cases this means setting it to 'now', so the item will be immediately downloadable; when using authorities with fallbacks, there is a few seconds' delay.)
Definition at line 363 of file dlstatus.c.
Referenced by download_status_increment_attempt(), download_status_increment_failure(), download_status_is_ready(), and learned_bridge_descriptor().
| STATIC int download_status_schedule_get_delay | ( | download_status_t * | dls, |
| int | min_delay, | ||
| time_t | now | ||
| ) |
Find the current delay for dls based on min_delay.
This function sets dls->next_attempt_at based on now, and returns the delay. Helper for download_status_increment_failure and download_status_increment_attempt.
Definition at line 153 of file dlstatus.c.
| STATIC int find_dl_min_delay | ( | const download_status_t * | dls, |
| const or_options_t * | options | ||
| ) |
Decide which download schedule we want to use based on descriptor type in dls and options.
Then, return the initial delay for that download schedule, in seconds.
Helper function for download_status_increment_failure(), download_status_reset(), and download_status_increment_attempt().
Definition at line 32 of file dlstatus.c.
| STATIC int next_random_exponential_delay | ( | int | delay, |
| int | base_delay | ||
| ) |
Advance one delay step. The algorithm will generate a random delay, such that each failure is possibly (random) longer than the ones before.
We then clamp that value to be no larger than max_delay, and return it.
The base_delay parameter is lowest possible delay time (can't be zero); the backoff_position parameter is the number of times we've generated a delay; and the delay argument is the most recently used delay.
Definition at line 129 of file dlstatus.c.
| STATIC void next_random_exponential_delay_range | ( | int * | low_bound_out, |
| int * | high_bound_out, | ||
| int | delay, | ||
| int | base_delay | ||
| ) |
As next_random_exponential_delay() below, but does not compute a random value. Instead, compute the range of values that next_random_exponential_delay() should use when computing its random value. Store the low bound into *low_bound_out, and the high bound into *high_bound_out. Guarantees that the low bound is strictly less than the high bound.
Definition at line 99 of file dlstatus.c.
1.9.4