From: Florian Forster Date: Thu, 20 Nov 2014 11:42:03 +0000 (+0100) Subject: src/oping.c: Improve comments. X-Git-Tag: liboping-1.8.0~3 X-Git-Url: https://git.verplant.org/?a=commitdiff_plain;h=a18b31772ddeab5d911f5cc8b7eecb340fabe879;p=liboping.git src/oping.c: Improve comments. Also remove dead code. --- diff --git a/src/oping.c b/src/oping.c index 3e735ff..a74cd42 100644 --- a/src/oping.c +++ b/src/oping.c @@ -167,17 +167,22 @@ typedef struct ping_context #endif /* The last n RTTs in the order they were sent. */ double history_by_time[HISTORY_SIZE_MAX]; - /* Current size of the history. This is a value between 0 and - * HISTORY_SIZE_MAX. */ + + /* Current number of entries in the history. This is a value between 0 + * and HISTORY_SIZE_MAX. */ size_t history_size; + + /* Number "received" entries in the history, i.e. non-NAN entries. */ + size_t history_received; + /* Index of the next RTT to be written to history_by_time. This wraps * around to 0 once the histroty has grown to HISTORY_SIZE_MAX. */ size_t history_index; - /* Number received replies, i.e. non-NAN entries. */ - size_t history_received; - /* The last n RTTs sorted by value. timed out packets are sorted to the - * back. */ + + /* The last history_size RTTs sorted by value. timed out packets (NAN + * entries) are sorted to the back. */ double history_by_value[HISTORY_SIZE_MAX]; + /* If set to true, history_by_value has to be re-calculated. */ _Bool history_dirty; @@ -282,10 +287,12 @@ static void clean_history (ping_context_t *ctx) /* {{{ */ /* Copy all values from by_time to by_value. */ memcpy (ctx->history_by_value, ctx->history_by_time, sizeof (ctx->history_by_time)); + /* Sort all RTTs. */ qsort (ctx->history_by_value, ctx->history_size, sizeof (ctx->history_by_value[0]), compare_double); + /* Update the number of received RTTs. */ ctx->history_received = 0; for (i = 0; i < ctx->history_size; i++) if (!isnan (ctx->history_by_value[i])) @@ -302,6 +309,7 @@ static double percentile_to_latency (ping_context_t *ctx, /* {{{ */ clean_history (ctx); + /* Not a single packet was received successfully. */ if (ctx->history_received == 0) return NAN; @@ -320,7 +328,7 @@ static double percentile_to_latency (ping_context_t *ctx, /* {{{ */ } /* }}} double percentile_to_latency */ #if USE_NCURSES -static double latency_to_percentile (ping_context_t *ctx, /* {{{ */ +static double latency_to_ratio (ping_context_t *ctx, /* {{{ */ double latency) { size_t low; @@ -329,6 +337,7 @@ static double latency_to_percentile (ping_context_t *ctx, /* {{{ */ clean_history (ctx); + /* Not a single packet was received successfully. */ if (ctx->history_received == 0) return NAN; @@ -340,6 +349,11 @@ static double latency_to_percentile (ping_context_t *ctx, /* {{{ */ else if (latency >= ctx->history_by_value[high]) return 100.0; + /* Do a binary search for the latency. This will work even when the + * exact latency is not in the array. If the latency is in the array + * multiple times, "low" will be set to the index of the last + * occurrence. The value at index "high" will be larger than the + * searched for latency (assured by the above "if" block. */ while ((high - low) > 1) { index = (high + low) / 2; @@ -358,8 +372,8 @@ static double latency_to_percentile (ping_context_t *ctx, /* {{{ */ else index = high; - return (100.0 * ((double) (index + 1)) / ((double) ctx->history_received)); -} /* }}} double latency_to_percentile */ + return (((double) (index + 1)) / ((double) ctx->history_received)); +} /* }}} double latency_to_ratio */ #endif static double context_get_packet_loss (const ping_context_t *ctx) /* {{{ */ @@ -962,6 +976,8 @@ static int update_graph_prettyping (ping_context_t *ctx, /* {{{ */ return (EINVAL); x_max -= 4; + /* Determine the first index in the history we need to draw + * the graph. */ history_offset = 0; if (((size_t) x_max) < ctx->history_size) { @@ -1481,29 +1497,16 @@ static void update_host_hook (pingobj_iter_t *iter, /* {{{ */ #if USE_NCURSES if (has_colors () == TRUE) { - double percentile; + double ratio; int color = OPING_GREEN; - percentile = latency_to_percentile (context, latency); - if (percentile < (100.0 * threshold_green)) - color = OPING_GREEN; - else if (percentile < (100.0 * threshold_yellow)) - color = OPING_YELLOW; - else - color = OPING_RED; - -#if 0 - if ((ratio_this <= threshold_green) - || ((ratio_prev < threshold_green) - && (ratio_this > threshold_green))) + ratio = latency_to_ratio (context, latency); + if (ratio < threshold_green) color = OPING_GREEN; - else if ((ratio_this <= threshold_yellow) - || ((ratio_prev < threshold_yellow) - && (ratio_this > threshold_yellow))) + else if (ratio < threshold_yellow) color = OPING_YELLOW; else color = OPING_RED; -#endif HOST_PRINTF ("%zu bytes from %s (%s): icmp_seq=%u ttl=%i ", data_len, context->host, context->addr,