/* constructor */
PyObject *
sr_py_distances_part_new(PyTypeObject *object, PyObject *args, PyObject *kwds)
{
int m, n, m_begin, n_begin;
unsigned long long len;
enum sr_distance_type dist_type;
unsigned long long checksum;
PyObject *dist_list;
if (!PyArg_ParseTuple(args, "iiiiKiKO", &m, &n, &m_begin, &n_begin, &len, &dist_type,
&checksum, &dist_list))
return NULL;
struct sr_distances_part *part = sr_distances_part_new(m, n, dist_type, m_begin, n_begin,
(size_t)len);
part->checksum = (uint32_t)checksum;
if (PyList_Check(dist_list))
{
part->distances = sr_malloc_array(sizeof(float), part->len);
int i;
for (i = 0; i < PyList_Size(dist_list); i++)
{
PyObject *item = PyList_GetItem(dist_list, i);
if (!item)
goto error;
double d = PyFloat_AsDouble(item);
if (PyErr_Occurred())
goto error;
part->distances[i] = (float)d;
}
}
else if (dist_list != Py_None)
{
PyErr_SetString(PyExc_TypeError, "distances must be list of floats or None");
goto error;
}
struct sr_py_distances_part *py_part =
PyObject_New(struct sr_py_distances_part, &sr_py_distances_part_type);
py_part->distances_part = part;
return (PyObject *)py_part;
error:
sr_distances_part_free(part, false);
return NULL;
}
struct sr_distances *
sr_distances_new(int m, int n)
{
struct sr_distances *distances = sr_malloc(sizeof(struct sr_distances));
/* The number of rows has to be smaller than columns. */
if (m >= n)
m = n - 1;
assert(m > 0 && n > 1 && m < n);
distances->m = m;
distances->n = n;
distances->distances = sr_malloc_array(
get_distance_position(distances, m - 1, n - 1) + 1,
sizeof(*distances->distances)
);
return distances;
}
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;
}
struct sr_koops_stacktrace *
sr_koops_stacktrace_from_json(struct sr_json_value *root, char **error_message)
{
if (!JSON_CHECK_TYPE(root, SR_JSON_OBJECT, "stacktrace"))
return NULL;
struct sr_koops_stacktrace *result = sr_koops_stacktrace_new();
/* Kernel version. */
if (!JSON_READ_STRING(root, "version", &result->version))
goto fail;
/* Raw oops text. */
if (!JSON_READ_STRING(root, "raw_oops", &result->raw_oops))
goto fail;
/* Kernel taint flags. */
struct sr_json_value *taint_flags = json_element(root, "taint_flags");
if (taint_flags)
{
if (!JSON_CHECK_TYPE(taint_flags, SR_JSON_ARRAY, "taint_flags"))
goto fail;
struct sr_json_value *flag_json;
FOR_JSON_ARRAY(taint_flags, flag_json)
{
if (!JSON_CHECK_TYPE(flag_json, SR_JSON_STRING, "taint flag"))
goto fail;
for (struct sr_taint_flag *f = sr_flags; f->name; f++)
{
if (0 == strcmp(f->name, flag_json->u.string.ptr))
{
*(bool *)((void *)result + f->member_offset) = true;
break;
}
}
/* XXX should we do something if nothing is set? */
}
}
/* Modules. */
struct sr_json_value *modules = json_element(root, "modules");
if (modules)
{
if (!JSON_CHECK_TYPE(modules, SR_JSON_ARRAY, "modules"))
goto fail;
unsigned i = 0;
size_t allocated = 128;
result->modules = sr_malloc_array(allocated, sizeof(char*));
struct sr_json_value *mod_json;
FOR_JSON_ARRAY(modules, mod_json)
{
if (!JSON_CHECK_TYPE(mod_json, SR_JSON_STRING, "module"))
goto fail;
/* need to keep the last element for NULL terminator */
if (i+1 == allocated)
{
allocated *= 2;
result->modules = sr_realloc(result->modules, allocated);
}
result->modules[i] = sr_strdup(mod_json->u.string.ptr);
i++;
}
result->modules[i] = NULL;
}
/* Frames. */
struct sr_json_value *frames = json_element(root, "frames");
if (frames)
{
if (!JSON_CHECK_TYPE(frames, SR_JSON_ARRAY, "frames"))
goto fail;
struct sr_json_value *frame_json;
FOR_JSON_ARRAY(frames, frame_json)
{
struct sr_koops_frame *frame = sr_koops_frame_from_json(frame_json,
error_message);
if (!frame)
goto fail;
result->frames = sr_koops_frame_append(result->frames, frame);
}
}
return result;
fail:
sr_koops_stacktrace_free(result);
return NULL;
}
