static int core_backtrace_is_duplicate(struct sr_stacktrace *bt1,
const char *bt2_text)
{
struct sr_thread *thread1 = sr_stacktrace_find_crash_thread(bt1);
if (thread1 == NULL)
{
log_notice("New stacktrace has no crash thread, disabling core stacktrace deduplicate");
dup_corebt_fini();
return 0;
}
int result;
char *error_message;
struct sr_stacktrace *bt2 = sr_stacktrace_parse(sr_abrt_type_from_type(type),
bt2_text, &error_message);
if (bt2 == NULL)
{
log_notice("Failed to parse backtrace, considering it not duplicate: %s", error_message);
free(error_message);
return 0;
}
struct sr_thread *thread2 = sr_stacktrace_find_crash_thread(bt2);
if (thread2 == NULL)
{
log_notice("Failed to get crash thread, considering it not duplicate");
result = 0;
goto end;
}
int length2 = sr_thread_frame_count(thread2);
if (length2 <= 0)
{
log_notice("Core backtrace has zero frames, considering it not duplicate");
result = 0;
goto end;
}
float distance = sr_distance(SR_DISTANCE_DAMERAU_LEVENSHTEIN, thread1, thread2);
log_info("Distance between backtraces: %f", distance);
result = (distance <= BACKTRACE_DUP_THRESHOLD);
end:
sr_stacktrace_free(bt2);
return result;
}
float
distance_jaro_winkler(struct sr_thread *thread1,
struct sr_thread *thread2)
{
assert(thread1->type == thread2->type);
int frame1_count = sr_thread_frame_count(thread1);
int frame2_count = sr_thread_frame_count(thread2);
if (frame1_count == 0 && frame2_count == 0)
return 1.0;
int max_frame_count = frame2_count;
if (max_frame_count < frame1_count)
max_frame_count = frame1_count;
int prefix_len = 0;
bool still_prefix = true;
float trans_count = 0, match_count = 0;
struct sr_frame *curr_frame = sr_thread_frames(thread1);
for (int i = 1; curr_frame; ++i)
{
bool match = false;
struct sr_frame *curr_frame2 = sr_thread_frames(thread2);
for (int j = 1; !match && curr_frame2; ++j)
{
/* Whether the prefix continues to be the same for both
* threads or not.
*/
if (i == j && 0 != sr_frame_cmp_distance(curr_frame, curr_frame2))
still_prefix = false;
/* Getting a match only if not too far away from each
* other and if functions aren't both unpaired unknown
* functions.
*/
if (abs(i - j) <= max_frame_count / 2 - 1 &&
0 == sr_frame_cmp_distance(curr_frame, curr_frame2))
{
match = true;
if (i != j)
++trans_count; // transposition in place
}
curr_frame2 = sr_frame_next(curr_frame2);
}
if (still_prefix)
++prefix_len;
if (match)
++match_count;
curr_frame = sr_frame_next(curr_frame);
}
trans_count /= 2;
if (prefix_len > 4)
prefix_len = 4;
if (0 == match_count)
return 0; // so as not to divide by 0
float dist_jaro = (match_count / (float)frame1_count +
match_count / (float)frame2_count +
(match_count - trans_count) / match_count) / 3;
/* How much weight we give to having common prefixes
* (always k < 0.25).
*/
float k = 0.2;
float dist = dist_jaro + (float)prefix_len * k * (1 - dist_jaro);
return dist;
}
float
distance_levenshtein(struct sr_thread *thread1,
struct sr_thread *thread2,
bool transposition)
{
assert(thread1->type == thread2->type);
int frame_count1 = sr_thread_frame_count(thread1);
int frame_count2 = sr_thread_frame_count(thread2);
int max_frame_count = frame_count2;
if (max_frame_count < frame_count1)
max_frame_count = frame_count1;
/* Avoid division by zero in case we get two empty threads */
if (max_frame_count == 0)
return 0.0;
int m = frame_count1 + 1;
int n = frame_count2 + 1;
// store only two last rows and columns instead of whole 2D array
SR_ASSERT(n <= SIZE_MAX - 1);
SR_ASSERT(m <= SIZE_MAX - (n + 1));
int *dist = sr_malloc_array(sizeof(int), m + n + 1);
int *dist1 = sr_malloc_array(sizeof(int), m + n + 1);
// first row and column having distance equal to their position
for (int i = m; i > 0; --i)
dist[m - i] = i;
for (int i = 0; i <= n; ++i)
dist[m + i] = i;
struct sr_frame *curr_frame2 = sr_thread_frames(thread2);
struct sr_frame *prev_frame = NULL;
struct sr_frame *prev_frame2 = NULL;
for (int j = 1; curr_frame2; ++j)
{
struct sr_frame *curr_frame = sr_thread_frames(thread1);
for (int i = 1; curr_frame; ++i)
{
int l = m + j - i;
int dist2 = dist1[l];
dist1[l] = dist[l];
int cost;
/*similar characters have distance equal to the previous
one diagonally, "??" functions aren't taken as
similar */
if (0 == sr_frame_cmp_distance(curr_frame, curr_frame2))
cost = 0;
else
{
// different ones takes the lowest value of all
// previous distances
cost = 1;
dist[l] += 1;
if (dist[l] > dist[l - 1] + 1)
dist[l] = dist[l - 1] + 1;
if (dist[l] > dist[l + 1] + 1)
dist[l] = dist[l + 1] + 1;
}
/*checking for transposition of two characters in both ways
taking into account that "??" functions are not similar*/
if (transposition &&
(i >= 2 && j >= 2 && dist[l] > dist2 + cost &&
0 == sr_frame_cmp_distance(curr_frame, prev_frame2) &&
0 == sr_frame_cmp_distance(prev_frame, curr_frame2)))
{
dist[l] = dist2 + cost;
}
prev_frame = curr_frame;
curr_frame = sr_frame_next(curr_frame);
}
prev_frame2 = curr_frame2;
curr_frame2 = sr_frame_next(curr_frame2);
}
int result = dist[n];
free(dist);
free(dist1);
return (float)result / max_frame_count;
}
static int core_backtrace_is_duplicate(struct sr_stacktrace *bt1,
const char *bt2_text)
{
struct sr_thread *thread1 = sr_stacktrace_find_crash_thread(bt1);
if (thread1 == NULL)
{
log_notice("New stacktrace has no crash thread, disabling core stacktrace deduplicate");
dup_corebt_fini();
return 0;
}
int result;
char *error_message;
struct sr_stacktrace *bt2 = sr_stacktrace_parse(sr_abrt_type_from_analyzer(analyzer),
bt2_text, &error_message);
if (bt2 == NULL)
{
log_notice("Failed to parse backtrace, considering it not duplicate: %s", error_message);
free(error_message);
return 0;
}
struct sr_thread *thread2 = sr_stacktrace_find_crash_thread(bt2);
if (thread2 == NULL)
{
log_notice("Failed to get crash thread, considering it not duplicate");
result = 0;
goto end;
}
int length2 = sr_thread_frame_count(thread2);
if (length2 <= 0)
{
log_notice("Core backtrace has zero frames, considering it not duplicate");
result = 0;
goto end;
}
/* This is an ugly workaround for https://github.com/abrt/btparser/issues/6 */
/*
int length1 = sr_core_thread_get_frame_count(thread1);
if (length1 <= 2 || length2 <= 2)
{
log_notice("Backtraces too short, falling back on full comparison");
result = (sr_core_thread_cmp(thread1, thread2) == 0);
goto end;
}
*/
float distance = sr_distance(SR_DISTANCE_DAMERAU_LEVENSHTEIN, thread1, thread2);
log_info("Distance between backtraces: %f", distance);
result = (distance <= BACKTRACE_DUP_THRESHOLD);
end:
sr_stacktrace_free(bt2);
return result;
}
