commit e4a11b890e7c5fe45dc1f5f271fbd8130ccc9c55 Author: Andrea Shepard andrea@torproject.org Date: Mon Sep 24 08:52:05 2012 -0700
Implement circuitmux_alloc()/circuitmux_free() and chanid/circid->muxinfo hash table --- src/or/circuitmux.c | 144 ++++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 143 insertions(+), 1 deletions(-)
diff --git a/src/or/circuitmux.c b/src/or/circuitmux.c index 45b72f2..d4866ca 100644 --- a/src/or/circuitmux.c +++ b/src/or/circuitmux.c @@ -10,6 +10,33 @@ #include "circuitmux.h"
/* + * Private typedefs for circuitmux.c + */ + +/* + * Map of muxinfos for circuitmux_t to use; struct is defined below (name + * of struct must match HT_HEAD line). + */ +typedef struct chanid_circid_muxinfo_map chanid_circid_muxinfo_map_t; + +/* + * Hash table entry (yeah, calling it chanid_circid_muxinfo_s seems to + * break the hash table code). + */ +typedef struct chanid_circid_muxinfo_t chanid_circid_muxinfo_t; + +/* + * Anything the mux wants to store per-circuit in the map; right now just + * a count of queued cells. + */ + +typedef struct circuit_muxinfo_s circuit_muxinfo_t; + +/* + * Structures for circuitmux.c + */ + +/* * A circuitmux is a collection of circuits; it tracks which subset * of the attached circuits are 'active' (i.e., have cells available * to transmit) and how many cells on each. It expoes three distinct @@ -40,6 +67,14 @@ */
struct circuitmux_s { + /* Keep count of attached, active circuits */ + unsigned int n_circuits, n_active_circuits; + + /* + * Map from (channel ID, circuit ID) pairs to circuit_muxinfo_t + */ + chanid_circid_muxinfo_map_t *chanid_circid_map; + /* * Double-linked ring of circuits with queued cells waiting for room to * free up on this connection's outbuf. Every time we pull cells from @@ -62,6 +97,113 @@ struct circuitmux_s { * The tick on which the cell_ewma_ts in active_circuit_pqueue last had * their ewma values rescaled. */ - unsigned active_circuit_pqueue_last_recalibrated; + unsigned int active_circuit_pqueue_last_recalibrated; +}; + +/* + * This struct holds whatever we want to store per attached circuit on a + * circuitmux_t; right now, just the count of queued cells. + */ + +struct circuit_muxinfo_s { + unsigned int cell_count; +}; + +/* + * A map from channel ID and circuit ID to a circuit_muxinfo_t for that + * circuit. + */ + +struct chanid_circid_muxinfo_t { + HT_ENTRY(chanid_circid_muxinfo_t) node; + uint64_t chan_id; + circid_t circ_id; + circuit_muxinfo_t muxinfo; };
+/* + * Static function declarations + */ + +static INLINE int +chanid_circid_entries_eq(chanid_circid_muxinfo_t *a, + chanid_circid_muxinfo_t *b); +static INLINE unsigned int +chanid_circid_entry_hash(chanid_circid_muxinfo_t *a); + +/* Function definitions */ + +/** + * Helper for chanid_circid_cell_count_map_t hash table: compare the channel + * ID and circuit ID for a and b, and return less than, equal to, or greater + * than zero appropriately. + */ + +static INLINE int +chanid_circid_entries_eq(chanid_circid_muxinfo_t *a, + chanid_circid_muxinfo_t *b) +{ + return a->chan_id == b->chan_id && a->circ_id == b->circ_id; +} + +/** + * Helper: return a hash based on circuit ID and channel ID in a. + */ + +static INLINE unsigned int +chanid_circid_entry_hash(chanid_circid_muxinfo_t *a) +{ + return (((unsigned int)(a->circ_id) << 8) ^ + ((unsigned int)((a->chan_id >> 32) & 0xffffffff)) ^ + ((unsigned int)(a->chan_id & 0xffffffff))); +} + +/* Declare the struct chanid_circid_muxinfo_map type */ +HT_HEAD(chanid_circid_muxinfo_map, chanid_circid_muxinfo_t); + +/* Emit a bunch of hash table stuff */ +HT_PROTOTYPE(chanid_circid_muxinfo_map, chanid_circid_muxinfo_t, node, + chanid_circid_entry_hash, chanid_circid_entries_eq); +HT_GENERATE(chanid_circid_muxinfo_map, chanid_circid_muxinfo_t, node, + chanid_circid_entry_hash, chanid_circid_entries_eq, 0.6, + malloc, realloc, free); + +/** + * Allocate a new circuitmux_t + */ + +circuitmux_t * +circuitmux_alloc(void) +{ + circuitmux_t *rv = NULL; + + rv = tor_malloc_zero(sizeof(*rv)); + rv->chanid_circid_map = tor_malloc_zero(sizeof(*( rv->chanid_circid_map))); + HT_INIT(chanid_circid_muxinfo_map, rv->chanid_circid_map); + + return rv; +} + +/** + * Free a circuitmux_t; the circuits must be detached first with + * circuitmux_detach_all_circuits(). + */ + +void +circuitmux_free(circuitmux_t *cmux) +{ + if (!cmux) return; + + tor_assert(cmux->n_circuits == 0); + tor_assert(cmux->n_active_circuits == 0); + + smartlist_free(cmux->active_circuit_pqueue); + + if (cmux->chanid_circid_map) { + HT_CLEAR(chanid_circid_muxinfo_map, cmux->chanid_circid_map); + tor_free(cmux->chanid_circid_map); + } + + tor_free(cmux); +} +