X-Git-Url: http://git.lttng.org./?a=blobdiff_plain;f=ltt%2Fbranches%2Fpoly%2Flttv%2Flttv%2Ftracecontext.c;h=7d560557654a2a239ff5fbbbad4a643d93c3f990;hb=1caf96c1c6694cce9ba58f5582de62572781494b;hp=98d91a69fe859dec9ade5b480d38e0f8b3734671;hpb=2c82c4dc9a5a322013842e0bf23008d164f369b6;p=lttv.git diff --git a/ltt/branches/poly/lttv/lttv/tracecontext.c b/ltt/branches/poly/lttv/lttv/tracecontext.c index 98d91a69..7d560557 100644 --- a/ltt/branches/poly/lttv/lttv/tracecontext.c +++ b/ltt/branches/poly/lttv/lttv/tracecontext.c @@ -26,9 +26,10 @@ #include #include #include +#include #include - +#define min(a,b) (((a)<(b))?(a):(b)) gint compare_tracefile(gconstpointer a, gconstpointer b) @@ -39,7 +40,7 @@ gint compare_tracefile(gconstpointer a, gconstpointer b) const LttvTracefileContext *trace_b = (const LttvTracefileContext *)b; if(likely(trace_a != trace_b)) { - comparison = ltt_time_compare(trace_b->timestamp, trace_a->timestamp); + comparison = ltt_time_compare(trace_a->timestamp, trace_b->timestamp); if(unlikely(comparison == 0)) { if(trace_a->index < trace_b->index) comparison = -1; else if(trace_a->index > trace_b->index) comparison = 1; @@ -52,11 +53,19 @@ gint compare_tracefile(gconstpointer a, gconstpointer b) return comparison; } +typedef struct _LttvTracefileContextPosition { + LttEventPosition *event; + LttvTracefileContext *tfc; + gboolean used; /* Tells if the tfc is at end of traceset position */ +} LttvTracefileContextPosition; + + struct _LttvTracesetContextPosition { - GArray *ep; /* Array of LttEventPosition */ - GArray *tfc; /* Array of corresponding - TracefileContext* */ - LttTime timestamp; /* Current time at the saved position */ + GArray *tfcp; /* Array of LttvTracefileContextPosition */ + LttTime timestamp; /* Current time at the saved position */ + /* If ltt_time_infinite : no position is + * set, else, a position is set (may be end + * of trace, with ep->len == 0) */ }; void lttv_context_init(LttvTracesetContext *self, LttvTraceset *ts) @@ -125,6 +134,8 @@ static void lttv_traceset_context_compute_time_span( trace = tc->t; ltt_trace_time_span_get(trace, &s, &e); + tc->time_span.start_time = s; + tc->time_span.end_time = e; if(i==0){ time_span->start_time = s; @@ -178,7 +189,6 @@ init(LttvTracesetContext *self, LttvTraceset *ts) self->traces = g_new(LttvTraceContext *, nb_trace); self->a = g_object_new(LTTV_ATTRIBUTE_TYPE, NULL); self->ts_a = lttv_traceset_attribute(ts); - self->sync_position = lttv_traceset_context_position_new(); for(i = 0 ; i < nb_trace ; i++) { tc = LTTV_TRACESET_CONTEXT_GET_CLASS(self)->new_trace_context(self); self->traces[i] = tc; @@ -231,6 +241,7 @@ init(LttvTracesetContext *self, LttvTraceset *ts) #endif //0 } + self->sync_position = lttv_traceset_context_position_new(self); self->pqueue = g_tree_new(compare_tracefile); lttv_process_traceset_seek_time(self, ltt_time_zero); lttv_traceset_context_compute_time_span(self, &self->time_span); @@ -620,6 +631,10 @@ static gboolean get_first(gpointer key, gpointer value, gpointer user_data) { return TRUE; } +#ifdef DEBUG +// Test to see if pqueue is traversed in the right order. +static LttTime test_time; + static gboolean test_tree(gpointer key, gpointer value, gpointer user_data) { LttvTracefileContext *tfc = (LttvTracefileContext *)key; @@ -628,15 +643,22 @@ static gboolean test_tree(gpointer key, gpointer value, gpointer user_data) { g_quark_to_string(ltt_tracefile_name(tfc->tf)), tfc->timestamp.tv_sec, tfc->timestamp.tv_nsec, tfc->index, tfc->t_context->index); + + if(user_data != NULL) { + if(((LttvTracefileContext *)user_data) == (LttvTracefileContext *)value) { + g_assert(compare_tracefile(user_data, value) == 0); + } else + g_assert(compare_tracefile(user_data, value) != 0); + } + g_assert(ltt_time_compare(test_time, tfc->timestamp) <= 0); + test_time.tv_sec = tfc->timestamp.tv_sec; + test_time.tv_nsec = tfc->timestamp.tv_nsec; - if(((LttvTracefileContext *)user_data) == (LttvTracefileContext *)value) { - g_assert(compare_tracefile(user_data, value) == 0); - } else - g_assert(compare_tracefile(user_data, value) != 0); //g_assert(((LttvTracefileContext *)user_data) != (LttvTracefileContext *)value); return FALSE; } +#endif //DEBUG @@ -659,6 +681,8 @@ void lttv_process_traceset_begin(LttvTracesetContext *self, } +enum read_state { LAST_NONE, LAST_OK, LAST_EMPTY }; + /* Note : a _middle must be preceded from a _seek or another middle */ guint lttv_process_traceset_middle(LttvTracesetContext *self, LttTime end, @@ -675,7 +699,9 @@ guint lttv_process_traceset_middle(LttvTracesetContext *self, unsigned count = 0; - guint read_ret = FALSE; + guint read_ret; + + enum read_state last_read_state = LAST_NONE; gboolean last_ret = FALSE; /* return value of the last hook list called */ @@ -709,44 +735,62 @@ guint lttv_process_traceset_middle(LttvTracesetContext *self, { return count; } - + /* Get the tracefile with an event for the smallest time found. If two or more tracefiles have events for the same time, hope that lookup and remove are consistent. */ #ifdef DEBUG + test_time.tv_sec = 0; + test_time.tv_nsec = 0; g_debug("test tree before remove"); g_tree_foreach(pqueue, test_tree, tfc); #endif //DEBUG g_tree_remove(pqueue, tfc); #ifdef DEBUG + test_time.tv_sec = 0; + test_time.tv_nsec = 0; g_debug("test tree after remove"); g_tree_foreach(pqueue, test_tree, tfc); #endif //DEBUG - count++; - e = ltt_tracefile_get_event(tfc->tf); - fac_id = ltt_event_facility_id(e); - ev_id = ltt_event_eventtype_id(e); - id = GET_HOOK_ID(fac_id, ev_id); - last_ret = lttv_hooks_call_merge(tfc->event, tfc, - lttv_hooks_by_id_get(tfc->event_by_id, id), tfc); + if(last_read_state != LAST_EMPTY) { + /* Only call hooks if the last read has given an event or if we are at the + * first pass (not if last read returned end of tracefile) */ + count++; + + fac_id = ltt_event_facility_id(e); + ev_id = ltt_event_eventtype_id(e); + id = GET_HOOK_ID(fac_id, ev_id); + last_ret = lttv_hooks_call_merge(tfc->event, tfc, + lttv_hooks_by_id_get(tfc->event_by_id, id), tfc); + } + read_ret = ltt_tracefile_read(tfc->tf); if(likely(!read_ret)) { - g_debug("An event is ready"); + //g_debug("An event is ready"); tfc->timestamp = ltt_event_time(e); - + g_assert(ltt_time_compare(tfc->timestamp, ltt_time_infinite) != 0); g_tree_insert(pqueue, tfc, tfc); +#ifdef DEBUG + test_time.tv_sec = 0; + test_time.tv_nsec = 0; + g_debug("test tree after event ready"); + g_tree_foreach(pqueue, test_tree, NULL); +#endif //DEBUG + + last_read_state = LAST_OK; } else { tfc->timestamp = ltt_time_infinite; - if(read_ret == ERANGE) + if(read_ret == ERANGE) { + last_read_state = LAST_EMPTY; g_debug("End of trace"); - else + } else g_error("Error happened in lttv_process_traceset_middle"); } } @@ -772,7 +816,10 @@ void lttv_process_traceset_end(LttvTracesetContext *self, /* Subtile modification : * if tracefile has no event at or after the time requested, it is not put in - * the queue, as the next read would fail. */ + * the queue, as the next read would fail. + * + * Don't forget to empty the traceset pqueue before calling this. + */ void lttv_process_trace_seek_time(LttvTraceContext *self, LttTime start) { guint i, nb_tracefile; @@ -781,25 +828,35 @@ void lttv_process_trace_seek_time(LttvTraceContext *self, LttTime start) LttvTracefileContext **tfc; - GTree *pqueue = self->ts_context->pqueue; - nb_tracefile = self->tracefiles->len; + GTree *pqueue = self->ts_context->pqueue; + for(i = 0 ; i < nb_tracefile ; i++) { tfc = &g_array_index(self->tracefiles, LttvTracefileContext*, i); - g_tree_remove(pqueue, *tfc); + //g_tree_remove(pqueue, *tfc); ret = ltt_tracefile_seek_time((*tfc)->tf, start); if(ret == EPERM) g_error("error in lttv_process_trace_seek_time seek"); if(ret == 0) { /* not ERANGE especially */ (*tfc)->timestamp = ltt_event_time(ltt_tracefile_get_event((*tfc)->tf)); + g_assert(ltt_time_compare((*tfc)->timestamp, ltt_time_infinite) != 0); g_tree_insert(pqueue, (*tfc), (*tfc)); } else { (*tfc)->timestamp = ltt_time_infinite; } } +#ifdef DEBUG + test_time.tv_sec = 0; + test_time.tv_nsec = 0; + g_debug("test tree after seek_time"); + g_tree_foreach(pqueue, test_tree, NULL); +#endif //DEBUG + + + } @@ -809,6 +866,9 @@ void lttv_process_traceset_seek_time(LttvTracesetContext *self, LttTime start) LttvTraceContext *tc; + g_tree_destroy(self->pqueue); + self->pqueue = g_tree_new(compare_tracefile); + nb_trace = lttv_traceset_number(self->ts); for(i = 0 ; i < nb_trace ; i++) { tc = self->traces[i]; @@ -821,23 +881,40 @@ gboolean lttv_process_traceset_seek_position(LttvTracesetContext *self, const LttvTracesetContextPosition *pos) { guint i; - - g_tree_destroy(self->pqueue); - self->pqueue = g_tree_new(compare_tracefile); - for(i=0;iep->len; i++) { - LttEventPosition **ep = &g_array_index(pos->ep, LttEventPosition*, i); - LttvTracefileContext **tfc = - &g_array_index(pos->tfc, LttvTracefileContext*, i); - if(*ep != NULL) { - if(ltt_tracefile_seek_position((*tfc)->tf, *ep) != 0) - return 1; - (*tfc)->timestamp = ltt_event_time(ltt_tracefile_get_event((*tfc)->tf)); - g_tree_insert(self->pqueue, (*tfc), (*tfc)); - } else { - (*tfc)->timestamp = ltt_time_infinite; + /* If a position is set, seek the traceset to this position */ + if(ltt_time_compare(pos->timestamp, ltt_time_infinite) != 0) { + g_tree_destroy(self->pqueue); + self->pqueue = g_tree_new(compare_tracefile); + + for(i=0;itfcp->len; i++) { + LttvTracefileContextPosition *tfcp = + &g_array_index(pos->tfcp, LttvTracefileContextPosition, i); + + + if(tfcp->used == TRUE) { + if(ltt_tracefile_seek_position(tfcp->tfc->tf, tfcp->event) != 0) + return 1; + tfcp->tfc->timestamp = + ltt_event_time(ltt_tracefile_get_event(tfcp->tfc->tf)); + g_assert(ltt_time_compare(tfcp->tfc->timestamp, + ltt_time_infinite) != 0); + g_tree_insert(self->pqueue, tfcp->tfc, tfcp->tfc); + + } else { + tfcp->tfc->timestamp = ltt_time_infinite; + } } } +#ifdef DEBUG + test_time.tv_sec = 0; + test_time.tv_nsec = 0; + g_debug("test tree after seek_position"); + g_tree_foreach(self->pqueue, test_tree, NULL); +#endif //DEBUG + + + return 0; } @@ -942,7 +1019,7 @@ lttv_trace_find_hook(LttTrace *t, GQuark facility, GQuark event, fac_id = g_array_index(facilities, guint, i); f = ltt_trace_get_facility_by_num(t, fac_id); - et = ltt_facility_eventtype_get_by_name(f, ltt_eventtype_name(et)); + et = ltt_facility_eventtype_get_by_name(f, event); if(unlikely(et == NULL)) goto event_error; thf = &g_array_index(th->fac_index, LttvTraceHookByFacility, fac_id); @@ -972,8 +1049,8 @@ lttv_trace_find_hook(LttTrace *t, GQuark facility, GQuark event, type_error: goto free; event_error: - g_error("Event type %s does not exist", - g_quark_to_string(ltt_eventtype_name(et))); + g_error("Event type does not exist for event %s", + g_quark_to_string(event)); goto free; facility_error: g_error("No %s facility", g_quark_to_string(facility)); @@ -993,47 +1070,78 @@ void lttv_trace_hook_destroy(LttvTraceHook *th) } -LttvTracesetContextPosition *lttv_traceset_context_position_new() + + +LttvTracesetContextPosition *lttv_traceset_context_position_new( + const LttvTracesetContext *self) { - LttvTracesetContextPosition *pos = g_new(LttvTracesetContextPosition,1); - pos->ep = g_array_sized_new(FALSE, TRUE, sizeof(LttEventPosition*), - 10); - pos->tfc = g_array_sized_new(FALSE, TRUE, sizeof(LttvTracefileContext*), - 10); + guint num_traces = lttv_traceset_number(self->ts); + guint tf_count = 0; + guint i; + + for(i=0; itraces[i]->tracefiles; + guint j; + guint num_tracefiles = tracefiles->len; + for(j=0;jtfcp = g_array_sized_new(FALSE, TRUE, + sizeof(LttvTracefileContextPosition), + tf_count); + g_array_set_size(pos->tfcp, tf_count); + for(i=0;itfcp->len;i++) { + LttvTracefileContextPosition *tfcp = + &g_array_index(pos->tfcp, LttvTracefileContextPosition, i); + tfcp->event = ltt_event_position_new(); + } + pos->timestamp = ltt_time_infinite; return pos; } -/* Save all positions, the ones not in the pqueue will have NULL +/* Save all positions, the ones with infinite time will have NULL * ep. */ +/* note : a position must be destroyed when a trace is added/removed from a + * traceset */ void lttv_traceset_context_position_save(const LttvTracesetContext *self, LttvTracesetContextPosition *pos) { guint i; guint num_traces = lttv_traceset_number(self->ts); - + guint tf_count = 0; + + pos->timestamp = ltt_time_infinite; + for(i=0; itraces[i]->tracefiles; guint j; guint num_tracefiles = tracefiles->len; for(j=0;jtfcp->len); LttvTracefileContext **tfc = &g_array_index(tracefiles, LttvTracefileContext*, j); + LttvTracefileContextPosition *tfcp = + &g_array_index(pos->tfcp, LttvTracefileContextPosition, tf_count); - LttEvent *event = ltt_tracefile_get_event((*tfc)->tf); - LttEventPosition *ep; + tfcp->tfc = *tfc; if(ltt_time_compare((*tfc)->timestamp, ltt_time_infinite) != 0) { - ep = ltt_event_position_new(); - ltt_event_position(event, ep); + LttEvent *event = ltt_tracefile_get_event((*tfc)->tf); + ltt_event_position(event, tfcp->event); if(ltt_time_compare((*tfc)->timestamp, pos->timestamp) < 0) pos->timestamp = (*tfc)->timestamp; + tfcp->used = TRUE; } else { - ep = NULL; + tfcp->used = FALSE; } - g_array_append_val(pos->tfc, *tfc); - g_array_append_val(pos->ep, ep); + + //g_array_append_val(pos->tfc, *tfc); + //g_array_append_val(pos->ep, ep); + tf_count++; } } @@ -1042,15 +1150,15 @@ void lttv_traceset_context_position_save(const LttvTracesetContext *self, void lttv_traceset_context_position_destroy(LttvTracesetContextPosition *pos) { int i; - LttEventPosition **ep; - for(i=0;iep->len;i++) { - ep = &g_array_index(pos->ep, LttEventPosition*, i); - if(*ep != NULL) - g_free(*ep); + for(i=0;itfcp->len;i++) { + LttvTracefileContextPosition *tfcp = + &g_array_index(pos->tfcp, LttvTracefileContextPosition, i); + g_free(tfcp->event); + tfcp->event = NULL; + tfcp->used = FALSE; } - g_array_free(pos->ep, TRUE); - g_array_free(pos->tfc, TRUE); + g_array_free(pos->tfcp, TRUE); g_free(pos); } @@ -1058,25 +1166,24 @@ void lttv_traceset_context_position_copy(LttvTracesetContextPosition *dest, const LttvTracesetContextPosition *src) { int i; - LttEventPosition **src_ep, **dest_ep; + LttvTracefileContextPosition *src_tfcp, *dest_tfcp; - g_array_set_size(dest->ep, src->ep->len); - g_array_set_size(dest->tfc, src->tfc->len); + g_assert(src->tfcp->len == src->tfcp->len); - for(i=0;iep->len;i++) { - src_ep = &g_array_index(src->ep, LttEventPosition*, i); - dest_ep = &g_array_index(dest->ep, LttEventPosition*, i); - if(*src_ep != NULL) { - *dest_ep = ltt_event_position_new(); + for(i=0;itfcp->len;i++) { + src_tfcp = + &g_array_index(src->tfcp, LttvTracefileContextPosition, i); + dest_tfcp = + &g_array_index(dest->tfcp, LttvTracefileContextPosition, i); + + dest_tfcp->used = src_tfcp->used; + dest_tfcp->tfc = src_tfcp->tfc; + + if(src_tfcp->used) { ltt_event_position_copy( - *dest_ep, - *src_ep); - } else - *dest_ep = NULL; - } - for(i=0;itfc->len;i++) { - g_array_index(dest->tfc, LttvTracefileContext*, i) = - g_array_index(src->tfc, LttvTracefileContext*, i); + dest_tfcp->event, + src_tfcp->event); + } } dest->timestamp = src->timestamp; } @@ -1087,30 +1194,29 @@ gint lttv_traceset_context_ctx_pos_compare(const LttvTracesetContext *self, int i; int ret = 0; - if(pos->ep->len == 0) { + if(pos->tfcp->len == 0) { if(lttv_traceset_number(self->ts) == 0) return 0; else return 1; } if(lttv_traceset_number(self->ts) == 0) return -1; - for(i=0;iep->len;i++) { - LttEventPosition *ep = g_array_index(pos->ep, LttEventPosition*, i); - LttvTracefileContext *tfc = - g_array_index(pos->tfc, LttvTracefileContext*, i); + for(i=0;itfcp->len;i++) { + LttvTracefileContextPosition *tfcp = + &g_array_index(pos->tfcp, LttvTracefileContextPosition, i); - if(ep == NULL) { - if(ltt_time_compare(tfc->timestamp, ltt_time_infinite) != 0) { + if(tfcp->used == FALSE) { + if(ltt_time_compare(tfcp->tfc->timestamp, ltt_time_infinite) < 0) { ret = -1; } } else { - if(ltt_time_compare(tfc->timestamp, ltt_time_infinite) == 0) { + if(ltt_time_compare(tfcp->tfc->timestamp, ltt_time_infinite) == 0) { ret = 1; } else { - LttEvent *event = ltt_tracefile_get_event(tfc->tf); + LttEvent *event = ltt_tracefile_get_event(tfcp->tfc->tf); ret = ltt_event_position_compare((LttEventPosition*)event, - ep); + tfcp->event); } } if(ret != 0) return ret; @@ -1127,40 +1233,40 @@ gint lttv_traceset_context_pos_pos_compare( int i, j; int ret; - if(pos1->ep->len == 0) { - if(pos2->ep->len == 0) return 0; + if(pos1->tfcp->len == 0) { + if(pos2->tfcp->len == 0) return 0; else return 1; } - if(pos2->ep->len == 0) + if(pos2->tfcp->len == 0) return -1; - for(i=0;iep->len;i++) { - LttEventPosition *ep1 = g_array_index(pos1->ep, LttEventPosition*, i); - LttvTracefileContext *tfc1 = g_array_index(pos1->tfc, - LttvTracefileContext*, i); + for(i=0;itfcp->len;i++) { + LttvTracefileContextPosition *tfcp1 = + &g_array_index(pos1->tfcp, LttvTracefileContextPosition, i); - if(ep1 != NULL) { - for(j=0;jep->len;j++) { - LttEventPosition *ep2 = g_array_index(pos2->ep, LttEventPosition*, j); - LttvTracefileContext *tfc2 = g_array_index(pos2->tfc, - LttvTracefileContext*, j); - if(tfc1 == tfc2) { - if(ep2 != NULL) - ret = ltt_event_position_compare(ep1, ep2); + if(tfcp1->used == TRUE) { + for(j=0;jtfcp->len;j++) { + LttvTracefileContextPosition *tfcp2 = + &g_array_index(pos2->tfcp, LttvTracefileContextPosition, j); + + if(tfcp1->tfc == tfcp2->tfc) { + if(tfcp2->used == TRUE) + ret = ltt_event_position_compare(tfcp1->event, tfcp2->event); else ret = -1; if(ret != 0) return ret; } } + } else { - for(j=0;jep->len;j++) { - LttEventPosition *ep2 = g_array_index(pos2->ep, LttEventPosition*, j); - LttvTracefileContext *tfc2 = g_array_index(pos2->tfc, - LttvTracefileContext*, j); - if(tfc1 == tfc2) { - if(ep2 != NULL) ret = 1; - } + for(j=0;jtfcp->len;j++) { + LttvTracefileContextPosition *tfcp2 = + &g_array_index(pos2->tfcp, LttvTracefileContextPosition, j); + + if(tfcp1->tfc == tfcp2->tfc) + if(tfcp2->used == TRUE) ret = 1; + if(ret != 0) return ret; } } } @@ -1205,5 +1311,260 @@ void lttv_process_traceset_get_sync_data(LttvTracesetContext *tsc) lttv_traceset_context_position_save(tsc, tsc->sync_position); } +struct seek_back_data { + guint first_event; /* Index of the first event in the array : we will always + overwrite at this position : this is a circular array. + */ + guint events_found; + guint n; /* number of events requested */ + GPtrArray *array; /* array of LttvTracesetContextPositions pointers */ + LttvFilter *filter; +}; + +static gint seek_back_event_hook(void *hook_data, void* call_data) +{ + struct seek_back_data *sd = (struct seek_back_data*)hook_data; + LttvTracefileContext *tfc = (LttvTracefileContext*)call_data; + LttvTracesetContext *tsc = tfc->t_context->ts_context; + LttvTracesetContextPosition *pos; + + if(sd->filter != NULL) { + if(!lttv_filter_tree_parse(sd->filter->head, + ltt_tracefile_get_event(tfc->tf), + tfc->tf, + tfc->t_context->t, + tfc)) + return FALSE; + } + + pos = (LttvTracesetContextPosition*)g_ptr_array_index (sd->array, + sd->first_event); + + lttv_traceset_context_position_save(tsc, pos); + + if(sd->first_event >= sd->array->len - 1) sd->first_event = 0; + else sd->first_event++; + + sd->events_found = min(sd->n, sd->events_found + 1); + + return FALSE; +} + +/* Seek back n events back from the current position. + * + * Parameters : + * @self The trace set context + * @n number of events to jump over + * @first_offset The initial offset value used. + * never put first_offset at ltt_time_zero. + * @time_seeker Function pointer of the function to use to seek time : + * either lttv_process_traceset_seek_time + * or lttv_state_traceset_seek_time_closest + * @filter The filter to call. + * + * Return value : the number of events found (might be lower than the number + * requested if beginning of traceset is reached). + * + * The first search will go back first_offset and try to find the last n events + * matching the filter. If there are not enough, it will try to go back from the + * new trace point from first_offset*2, and so on, until beginning of trace or n + * events are found. + * + * Note : this function does not take in account the LttvFilter : use the + * similar function found in state.c instead. + * + * Note2 : the caller must make sure that the LttvTracesetContext does not + * contain any hook, as process_traceset_middle is used in this routine. + */ +guint lttv_process_traceset_seek_n_backward(LttvTracesetContext *self, + guint n, LttTime first_offset, + seek_time_fct time_seeker, + LttvFilter *filter) +{ + if(lttv_traceset_number(self->ts) == 0) return 0; + g_assert(ltt_time_compare(first_offset, ltt_time_zero) != 0); + + guint i; + LttvTracesetContextPosition *next_iter_end_pos = + lttv_traceset_context_position_new(self); + LttvTracesetContextPosition *end_pos = + lttv_traceset_context_position_new(self); + LttvTracesetContextPosition *saved_pos = + lttv_traceset_context_position_new(self); + LttTime time; + LttTime time_offset; + struct seek_back_data sd; + LttvHooks *hooks = lttv_hooks_new(); + + sd.first_event = 0; + sd.events_found = 0; + sd.array = g_ptr_array_sized_new(n); + sd.filter = filter; + sd.n = n; + g_ptr_array_set_size(sd.array, n); + for(i=0;itime_span.end_time) > 0) { + time = self->time_span.end_time; + } + time_offset = first_offset; + + lttv_hooks_add(hooks, seek_back_event_hook, &sd, LTTV_PRIO_DEFAULT); + + lttv_process_traceset_begin(self, NULL, NULL, NULL, hooks, NULL); + + while(1) { + /* stop criteria : - n events found + * - time < beginning of trace */ + if(ltt_time_compare(time, self->time_span.start_time) < 0) break; + + lttv_traceset_context_position_copy(end_pos, next_iter_end_pos); + + /* We must seek the traceset back to time - time_offset */ + /* this time becomes the new reference time */ + time = ltt_time_sub(time, time_offset); + + time_seeker(self, time); + lttv_traceset_context_position_save(self, next_iter_end_pos); + /* Resync the time in case of a seek_closest */ + time = lttv_traceset_context_position_get_time(next_iter_end_pos); + if(ltt_time_compare(time, self->time_span.end_time) > 0) { + time = self->time_span.end_time; + } + + /* Process the traceset, calling a hook which adds events + * to the array, overwriting the tail. It changes first_event and + * events_found too. */ + /* We would like to have a clean context here : no other hook than our's */ + + lttv_process_traceset_middle(self, ltt_time_infinite, + G_MAXUINT, end_pos); + + if(sd.events_found < n) { + if(sd.first_event > 0) { + /* Save the first position */ + LttvTracesetContextPosition *pos = + (LttvTracesetContextPosition*)g_ptr_array_index (sd.array, 0); + lttv_traceset_context_position_copy(saved_pos, pos); + } + g_assert(n-sd.events_found <= sd.array->len); + /* Change array size to n - events_found */ + for(i=n-sd.events_found;ilen;i++) { + LttvTracesetContextPosition *pos = + (LttvTracesetContextPosition*)g_ptr_array_index (sd.array, i); + lttv_traceset_context_position_destroy(pos); + } + g_ptr_array_set_size(sd.array, n-sd.events_found); + sd.first_event = 0; + + } else break; /* Second end criterion : n events found */ + + time_offset = ltt_time_mul(time_offset, BACKWARD_SEEK_MUL); + } + + lttv_traceset_context_position_destroy(end_pos); + lttv_traceset_context_position_destroy(next_iter_end_pos); + + lttv_process_traceset_end(self, NULL, NULL, NULL, hooks, NULL); + + if(sd.events_found >= n) { + /* Seek the traceset to the first event in the circular array */ + LttvTracesetContextPosition *pos = + (LttvTracesetContextPosition*)g_ptr_array_index (sd.array, + sd.first_event); + g_assert(lttv_process_traceset_seek_position(self, pos) == 0); + } else { + /* Will seek to the last saved position : in the worst case, it will be the + * original position (if events_found is 0) */ + g_assert(lttv_process_traceset_seek_position(self, saved_pos) == 0); + } + + for(i=0;ilen;i++) { + LttvTracesetContextPosition *pos = + (LttvTracesetContextPosition*)g_ptr_array_index (sd.array, i); + lttv_traceset_context_position_destroy(pos); + } + g_ptr_array_free(sd.array, TRUE); + + lttv_hooks_destroy(hooks); + + lttv_traceset_context_position_destroy(saved_pos); + + return sd.events_found; +} + + +struct seek_forward_data { + guint event_count; /* event counter */ + guint n; /* requested number of events to jump over */ + LttvFilter *filter; +}; + +static gint seek_forward_event_hook(void *hook_data, void* call_data) +{ + struct seek_forward_data *sd = (struct seek_forward_data*)hook_data; + LttvTracefileContext *tfc = (LttvTracefileContext*)call_data; + + if(sd->filter != NULL) { + if(!lttv_filter_tree_parse(sd->filter->head, + ltt_tracefile_get_event(tfc->tf), + tfc->tf, + tfc->t_context->t, + tfc)) + return FALSE; + } + + sd->event_count++; + + if(sd->event_count >= sd->n) + return TRUE; + else + return FALSE; +} + +/* Seek back n events forward from the current position + * + * Parameters : + * @self the trace set context + * @n number of events to jump over + * @filter filter to call. + * + * returns : the number of events jumped over (may be less than requested if end + * of traceset reached) */ +guint lttv_process_traceset_seek_n_forward(LttvTracesetContext *self, + guint n, LttvFilter *filter) +{ + struct seek_forward_data sd; + sd.event_count = 0; + sd.n = n; + sd.filter = filter; + LttvHooks *hooks = lttv_hooks_new(); + + lttv_hooks_add(hooks, seek_forward_event_hook, &sd, LTTV_PRIO_DEFAULT); + + lttv_process_traceset_begin(self, NULL, NULL, NULL, hooks, NULL); + + /* it will end on the end of traceset, or the fact that the + * hook returns TRUE. + */ + lttv_process_traceset_middle(self, ltt_time_infinite, + G_MAXUINT, NULL); + + /* Here, our position is either the end of traceset, or the exact position + * after n events : leave it like this. */ + + lttv_process_traceset_end(self, NULL, NULL, NULL, hooks, NULL); + + lttv_hooks_destroy(hooks); + + return sd.event_count; +}