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/* Licensed under LGPLv2.1+ - see LICENSE file for details */
#ifdef CCAN_LIKELY_DEBUG
#include <ccan/likely/likely.h>
#include <ccan/hash/hash.h>
#include <ccan/htable/htable.h>
#include <stdlib.h>
#include <stdio.h>
static struct htable *htable;
struct trace {
const char *condstr;
const char *file;
unsigned int line;
bool expect;
unsigned long count, right;
};
/* We hash the pointers, which will be identical for same call. */
static unsigned long hash_trace(const struct trace *trace)
{
return hash_pointer(trace->condstr,
hash_pointer(trace->file,
trace->line + trace->expect));
}
static bool hash_cmp(const void *htelem, void *cmpdata)
{
const struct trace *t1 = htelem, *t2 = cmpdata;
return t1->condstr == t2->condstr
&& t1->file == t2->file
&& t1->line == t2->line
&& t1->expect == t2->expect;
}
static size_t rehash(const void *elem, void *priv)
{
return hash_trace(elem);
}
static void init_trace(struct trace *trace,
const char *condstr, const char *file, unsigned int line,
bool expect)
{
trace->condstr = condstr;
trace->file = file;
trace->line = line;
trace->expect = expect;
trace->count = trace->right = 0;
}
static struct trace *add_trace(const char *condstr,
const char *file, unsigned int line, bool expect)
{
struct trace *trace = malloc(sizeof(*trace));
init_trace(trace, condstr, file, line, expect);
htable_add(htable, hash_trace(trace), trace);
return trace;
}
long _likely_trace(bool cond, bool expect,
const char *condstr,
const char *file, unsigned int line)
{
struct trace *p, trace;
if (!htable)
htable = htable_new(rehash, NULL);
init_trace(&trace, condstr, file, line, expect);
p = htable_get(htable, hash_trace(&trace), hash_cmp, &trace);
if (!p)
p = add_trace(condstr, file, line, expect);
p->count++;
if (cond == expect)
p->right++;
return cond;
}
struct get_stats_info {
struct trace *worst;
unsigned int min_hits;
double worst_ratio;
};
static double right_ratio(const struct trace *t)
{
return (double)t->right / t->count;
}
static void get_stats(struct trace *trace, struct get_stats_info *info)
{
if (trace->count < info->min_hits)
return;
if (right_ratio(trace) < info->worst_ratio) {
info->worst = trace;
info->worst_ratio = right_ratio(trace);
}
}
const char *likely_stats(unsigned int min_hits, unsigned int percent)
{
struct get_stats_info info;
struct htable_iter i;
char *ret;
struct trace *trace;
if (!htable)
return NULL;
info.min_hits = min_hits;
info.worst = NULL;
info.worst_ratio = 2;
/* This is O(n), but it's not likely called that often. */
for (trace = htable_first(htable, &i);
trace;
trace = htable_next(htable,&i)) {
get_stats(trace, &info);
}
if (info.worst_ratio * 100 > percent)
return NULL;
ret = malloc(strlen(info.worst->condstr) +
strlen(info.worst->file) +
sizeof(long int) * 8 +
sizeof("%s:%u:%slikely(%s) correct %u%% (%lu/%lu)"));
sprintf(ret, "%s:%u:%slikely(%s) correct %u%% (%lu/%lu)",
info.worst->file, info.worst->line,
info.worst->expect ? "" : "un", info.worst->condstr,
(unsigned)(info.worst_ratio * 100),
info.worst->right, info.worst->count);
htable_del(htable, hash_trace(info.worst), info.worst);
free(info.worst);
return ret;
}
#endif /*CCAN_LIKELY_DEBUG*/
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