diff options
Diffstat (limited to 'src/core/bandwidth_policy.c')
| -rw-r--r-- | src/core/bandwidth_policy.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/src/core/bandwidth_policy.c b/src/core/bandwidth_policy.c new file mode 100644 index 0000000..47a59d7 --- /dev/null +++ b/src/core/bandwidth_policy.c @@ -0,0 +1,229 @@ +#include "hybbx/bandwidth_policy.h" +#include "hybbx/service.h" +#include "hybbx/session.h" +#include "hybbx/plugin.h" +#include "hybbx/log.h" + +#include <stdio.h> +#include <string.h> +#include <time.h> + +#define BW_USER_MAX 128u + +/** Lower = sacrificed first under pressure (AX.25 users before full-duplex TCP). */ +#define BW_PRIORITY_AX25_USER 0 +#define BW_PRIORITY_TCP_USER 1 + +typedef struct bw_user_entry { + hybbx_session_t *session; + time_t connected_at; + int sacrifice_priority; +} bw_user_entry_t; + +typedef struct bw_collect_ctx { + bw_user_entry_t entries[BW_USER_MAX]; + unsigned count; +} bw_collect_ctx_t; + +static int session_sacrifice_priority(const hybbx_session_t *session) +{ + const hybbx_transport_plugin_t *transport; + + if (session == NULL) { + return -1; + } + + transport = session->transport; + if (transport == NULL) { + return -1; + } + + switch (transport->kind) { + case HYBBX_TRANSPORT_PACKET_RADIO: + return BW_PRIORITY_AX25_USER; + case HYBBX_TRANSPORT_TELNET: + return BW_PRIORITY_TCP_USER; + case HYBBX_TRANSPORT_CIRCUIT: + default: + return -1; + } +} + +static void bw_collect_visitor(hybbx_session_t *session, void *userdata) +{ + bw_collect_ctx_t *ctx = (bw_collect_ctx_t *)userdata; + int priority; + + if (ctx == NULL || session == NULL) { + return; + } + + priority = session_sacrifice_priority(session); + if (priority < 0 || !hybbx_session_logged_in(session)) { + return; + } + + if (ctx->count >= BW_USER_MAX) { + return; + } + + ctx->entries[ctx->count].session = session; + ctx->entries[ctx->count].connected_at = hybbx_session_connected_at(session); + ctx->entries[ctx->count].sacrifice_priority = priority; + ctx->count++; +} + +static void bw_sort_victims_first(bw_collect_ctx_t *ctx) +{ + unsigned i; + unsigned j; + + if (ctx == NULL) { + return; + } + + /* Lowest sacrifice_priority first (AX.25), then newest connected_at. */ + for (i = 0; i + 1 < ctx->count; i++) { + for (j = i + 1; j < ctx->count; j++) { + int swap = 0; + + if (ctx->entries[j].sacrifice_priority < + ctx->entries[i].sacrifice_priority) { + swap = 1; + } else if (ctx->entries[j].sacrifice_priority == + ctx->entries[i].sacrifice_priority) { + if (ctx->entries[j].connected_at > + ctx->entries[i].connected_at) { + swap = 1; + } else if (ctx->entries[j].connected_at == + ctx->entries[i].connected_at && + hybbx_session_id(ctx->entries[j].session) > + hybbx_session_id(ctx->entries[i].session)) { + swap = 1; + } + } + + if (swap) { + bw_user_entry_t tmp = ctx->entries[i]; + + ctx->entries[i] = ctx->entries[j]; + ctx->entries[j] = tmp; + } + } + } +} + +static hybbx_session_t *bw_first_unpaused(const bw_collect_ctx_t *ctx) +{ + unsigned i; + + if (ctx == NULL) { + return NULL; + } + + for (i = 0; i < ctx->count; i++) { + if (!hybbx_session_bandwidth_paused(ctx->entries[i].session)) { + return ctx->entries[i].session; + } + } + + return NULL; +} + +static hybbx_session_t *bw_first_paused(const bw_collect_ctx_t *ctx) +{ + unsigned i; + + if (ctx == NULL) { + return NULL; + } + + for (i = 0; i < ctx->count; i++) { + if (hybbx_session_bandwidth_paused(ctx->entries[i].session)) { + return ctx->entries[i].session; + } + } + + return NULL; +} + +unsigned hybbx_bandwidth_policy_user_count(hybbx_service_t *service) +{ + bw_collect_ctx_t ctx; + + if (service == NULL) { + return 0; + } + + memset(&ctx, 0, sizeof(ctx)); + hybbx_service_visit_sessions(service, bw_collect_visitor, &ctx); + return ctx.count; +} + +unsigned hybbx_bandwidth_policy_apply(hybbx_service_t *service, + hybbx_circuit_balance_action_t action) +{ + bw_collect_ctx_t ctx; + unsigned i; + unsigned affected = 0; + + if (service == NULL) { + return 0; + } + + memset(&ctx, 0, sizeof(ctx)); + hybbx_service_visit_sessions(service, bw_collect_visitor, &ctx); + if (ctx.count == 0) { + return 0; + } + + bw_sort_victims_first(&ctx); + + switch (action) { + case HYBBX_CIRCUIT_BAL_PAUSE: { + hybbx_session_t *target = bw_first_unpaused(&ctx); + + if (target != NULL) { + hybbx_session_set_bandwidth_paused(target, 1); + hybbx_log_stats("[bandwidth] paused user %s (QoS: AX.25 before TCP)", + hybbx_session_display_name(target)); + affected = 1; + } + break; + } + case HYBBX_CIRCUIT_BAL_BREAK: { + hybbx_session_t *target = bw_first_paused(&ctx); + + if (target == NULL && ctx.count > 0) { + target = ctx.entries[0].session; + } + + if (target != NULL) { + hybbx_log_stats("[bandwidth] disconnecting user %s (break)", + hybbx_session_display_name(target)); + hybbx_session_disconnect_bandwidth(target); + affected = 1; + } + break; + } + case HYBBX_CIRCUIT_BAL_CANCEL: + for (i = 0; i + 1 < ctx.count; i++) { + hybbx_log_stats("[bandwidth] disconnecting user %s (cancel)", + hybbx_session_display_name(ctx.entries[i].session)); + hybbx_session_disconnect_bandwidth(ctx.entries[i].session); + affected++; + } + break; + case HYBBX_CIRCUIT_BAL_RESUME: + for (i = 0; i < ctx.count; i++) { + hybbx_session_set_bandwidth_paused(ctx.entries[i].session, 0); + } + affected = ctx.count; + break; + case HYBBX_CIRCUIT_BAL_NONE: + default: + break; + } + + return affected; +} |