curl/tests/unit/unit3211.c
Stefan Eissing 909af1a43b
multi: do transfer book keeping using mid
Change multi's book keeping of transfers to no longer use lists, but a
special table and bitsets for unsigned int values.

`multi-xfers` is the `uint_tbl` where `multi_add_handle()` inserts a new
transfer which assigns it a unique identifier `mid`. Use bitsets to keep
track of transfers that are in state "process" or "pending" or
"msgsent".

Use sparse bitsets to replace `conn->easyq` and event handlings tracking
of transfers per socket. Instead of pointers, keep the mids involved.

Provide base data structures and document them in docs/internal:
* `uint_tbl`: a table of transfers with `mid` as lookup key,
   handing out a mid for adds between 0 - capacity.
* `uint_bset`: a bitset keeping unsigned ints from 0 - capacity.
* `uint_spbset`: a sparse bitset for keeping a small number of
  unsigned int values
* `uint_hash`: for associating `mid`s with a pointer.

This makes the `mid` the recommended way to refer to transfers inside
the same multi without risk of running into a UAF.

Modifying table and bitsets is safe while iterating over them. Overall
memory requirements are lower as with the double linked list apprach.

Closes #16761
2025-04-17 17:28:38 +02:00

153 lines
5.1 KiB
C

/***************************************************************************
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* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
* Copyright (C) Daniel Stenberg, <daniel@haxx.se>, et al.
*
* This software is licensed as described in the file COPYING, which
* you should have received as part of this distribution. The terms
* are also available at https://curl.se/docs/copyright.html.
*
* You may opt to use, copy, modify, merge, publish, distribute and/or sell
* copies of the Software, and permit persons to whom the Software is
* furnished to do so, under the terms of the COPYING file.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
* SPDX-License-Identifier: curl
*
***************************************************************************/
#include "curlcheck.h"
#include "urldata.h"
#include "uint-bset.h"
#include "curl_trc.h"
static CURLcode unit_setup(void)
{
return CURLE_OK;
}
static unsigned int s1[] = { /* spread numbers, some at slot edges */
0, 1, 4, 17, 63, 64, 65, 66,
90, 99,
};
static unsigned int s2[] = { /* set with all bits in slot1 set */
64, 65, 66, 67, 68, 69, 70, 71,
72, 73, 74, 75, 76, 77, 78, 79,
80, 81, 82, 83, 84, 85, 86, 87,
88, 89, 90, 91, 92, 93, 94, 95,
96, 97, 98, 99, 100, 101, 102, 103,
104, 105, 106, 107, 108, 109, 110, 111,
112, 113, 114, 115, 116, 117, 118, 119,
120, 121, 122, 123, 124, 125, 126, 127,
};
static void check_set(const char *name, unsigned int capacity,
unsigned int *s, size_t slen)
{
struct uint_bset bset;
size_t i, j;
unsigned int n, c;
fprintf(stderr, "test %s, capacity=%u, %zu numbers\n",
name, capacity, slen);
Curl_uint_bset_init(&bset);
fail_unless(!Curl_uint_bset_resize(&bset, capacity), "bset resize failed");
c = Curl_uint_bset_capacity(&bset);
fail_unless(c == (((capacity + 63) / 64) * 64), "wrong capacity");
Curl_uint_bset_clear(&bset);
c = Curl_uint_bset_count(&bset);
fail_unless(c == 0, "set count is not 0");
for(i = 0; i < slen; ++i) { /* add all */
fail_unless(Curl_uint_bset_add(&bset, s[i]), "failed to add");
for(j = i + 1; j < slen; ++j)
fail_unless(!Curl_uint_bset_contains(&bset, s[j]), "unexpectedly found");
}
for(i = 0; i < slen; ++i) { /* all present */
fail_unless(Curl_uint_bset_contains(&bset, s[i]), "failed presence check");
}
/* iterator over all numbers */
fail_unless(Curl_uint_bset_first(&bset, &n), "first failed");
fail_unless(n == s[0], "first not correct number");
for(i = 1; i < slen; ++i) {
fail_unless(Curl_uint_bset_next(&bset, n, &n), "next failed");
if(n != s[i]) {
fprintf(stderr, "expected next to be %u, not %u\n", s[i], n);
fail_unless(n == s[i], "next not correct number");
}
}
/* Adding capacity number does not work (0 - capacity-1) */
c = Curl_uint_bset_capacity(&bset);
fail_unless(!Curl_uint_bset_add(&bset, c), "add out of range worked");
/* The count it correct */
c = Curl_uint_bset_count(&bset);
fail_unless(c == slen, "set count is wrong");
for(i = 0; i < slen; i += 2) { /* remove every 2nd */
Curl_uint_bset_remove(&bset, s[i]);
fail_unless(!Curl_uint_bset_contains(&bset, s[i]), "unexpectedly found");
}
for(i = 1; i < slen; i += 2) { /* others still there */
fail_unless(Curl_uint_bset_contains(&bset, s[i]), "unexpectedly gone");
}
/* The count is half */
c = Curl_uint_bset_count(&bset);
fail_unless(c == slen/2, "set count is wrong");
Curl_uint_bset_clear(&bset);
c = Curl_uint_bset_count(&bset);
fail_unless(c == 0, "set count is not 0");
for(i = 0; i < slen; i++) { /* none present any longer */
fail_unless(!Curl_uint_bset_contains(&bset, s[i]), "unexpectedly there");
}
for(i = 0; i < slen; ++i) { /* add all again */
fail_unless(Curl_uint_bset_add(&bset, s[i]), "failed to add");
}
fail_unless(!Curl_uint_bset_resize(&bset, capacity * 2),
"resize double failed");
for(i = 0; i < slen; i++) { /* all still present after resize */
fail_unless(Curl_uint_bset_contains(&bset, s[i]), "unexpectedly lost");
}
fail_unless(!Curl_uint_bset_resize(&bset, capacity), "resize back failed");
for(i = 0; i < slen; i++) /* all still present after resize back */
fail_unless(Curl_uint_bset_contains(&bset, s[i]), "unexpectedly lost");
fail_unless(!Curl_uint_bset_resize(&bset, capacity/2), "resize half failed");
/* halfed the size, what numbers remain in set? */
c = Curl_uint_bset_capacity(&bset);
n = 0;
for(i = 0; i < slen; ++i) {
if(s[i] < c)
++n;
}
fail_unless(n == Curl_uint_bset_count(&bset), "set count(halfed) wrong");
for(i = 0; i < n; i++) /* still present after resize half */
fail_unless(Curl_uint_bset_contains(&bset, s[i]), "unexpectedly lost");
Curl_uint_bset_destroy(&bset);
}
static void unit_stop(void)
{
}
UNITTEST_START
check_set("s1", 100, s1, CURL_ARRAYSIZE(s1));
check_set("s2", 1000, s2, CURL_ARRAYSIZE(s2));
UNITTEST_STOP