SymbX/systemd
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

sd-journal: rewrite conditions for test result and direction

Browse Source 
No functional change, just refactoring. Hopefully the condition is more
descriptive now.
This commit is contained in:
Yu Watanabe
2023-10-06 09:55:00 +09:00
parent 0096914023
commit d67078b4a3
1 changed files with 35 additions and 22 deletions
Download Patch File Download Diff File Expand all files Collapse all files
src/libsystemd/sd-journal/journal-file.c
+35 -22
View File
@@ -3107,7 +3107,6 @@ static int generic_array_bisect_plus_one(
uint64_t *ret_offset) {
int r;
bool step_back = false;
assert(f);
assert(test_object);
@@ -3115,38 +3114,52 @@ static int generic_array_bisect_plus_one(
if (n <= 0)
return 0;
/* This bisects the array in object 'first', but first checks
* an extra */
/* This bisects the array in object 'first', but first checks an extra. */
r = test_object(f, extra, needle);
if (r < 0)
return r;
if (r == TEST_FOUND)
r = direction == DIRECTION_DOWN ? TEST_RIGHT : TEST_LEFT;
if (direction == DIRECTION_DOWN) {
/* If we are going downwards, then we need to return the first object that passes the test.
* When there is no object that passes the test, we need to return the first object that
* test_object() returns TEST_RIGHT for. */
if (IN_SET(r,
TEST_FOUND, /* The 'extra' object passes the test. Hence, this is the first
* object that passes the test. */
TEST_RIGHT)) /* The 'extra' object is the first object that test_object() returns
* TEST_RIGHT for, and no object exists even in the chained arrays
* that passes the test. */
goto use_extra; /* The 'extra' object is exactly the one we are looking for. It is
* not necessary to bisect the chained arrays. */
/* if we are looking with DIRECTION_UP then we need to first
see if in the actual array there is a matching entry, and
return the last one of that. But if there isn't any we need
to return this one. Hence remember this, and return it
below. */
if (r == TEST_LEFT)
step_back = direction == DIRECTION_UP;
/* Otherwise, the 'extra' object is not the one we are looking for. Search in the arrays. */
if (r == TEST_RIGHT) {
if (direction == DIRECTION_DOWN)
goto found;
else
return 0;
} else {
/* If we are going upwards, then we need to return the last object that passes the test.
* When there is no object that passes the test, we need to return the the last object that
* test_object() returns TEST_LEFT for. */
if (r == TEST_RIGHT)
return 0; /* Not only the 'extra' object, but also all objects in the chained arrays
* will never get TEST_FOUND or TEST_LEFT. The object we are looking for
* does not exist. */
/* Even if the 'extra' object passes the test, there may be multiple objects in the arrays
* that also pass the test. Hence, we need to bisect the arrays for finding the last matching
* object. */
}
r = generic_array_bisect(f, first, n-1, needle, test_object, direction, ret_object, ret_offset, NULL);
if (r != 0)
return r; /* When > 0, the found object is the first (or last, when DIRECTION_UP) object.
* Hence, return the found object now. */
if (r == 0 && step_back)
goto found;
/* No matching object found in the chained arrays.
* DIRECTION_DOWN : the 'extra' object neither matches the condition. There is no matching object.
* DIRECTION_UP : the 'extra' object matches the condition. So, return it. */
if (direction == DIRECTION_DOWN)
return 0;
return r;
found:
use_extra:
if (ret_object) {
r = journal_file_move_to_object(f, OBJECT_ENTRY, extra, ret_object);
if (r < 0)