romenskiy2012/curl
1
0
Fork 0
mirror of https://github.com/curl/curl.git synced 2026-08-25 05:23:32 +03:00
Code Issues Projects Releases Packages Wiki Activity

multi: do transfer book keeping using mid

Browse source 
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
This commit is contained in:
Stefan Eissing 2025-03-25 09:47:40 +01:00 • committed by Daniel Stenberg
parent 02e9690c3e
commit 909af1a43b
No known key found for this signature in database
GPG key ID: 5CC908FDB71E12C2
41 changed files with 2553 additions and 424 deletions
Download patch file Download diff file Expand all files Collapse all files

4
include/curl/system.h
View file

@ -336,6 +336,8 @@
# define CURL_FORMAT_CURL_OFF_TU "llu"
# define CURL_SUFFIX_CURL_OFF_T LL
# define CURL_SUFFIX_CURL_OFF_TU ULL
# define CURL_POPCOUNT64(x) __builtin_popcountll(x)
# define CURL_CTZ64(x) __builtin_ctzll(x)
# elif defined(__LP64__) || \
defined(__x86_64__) || defined(__ppc64__) || defined(__sparc64__) || \
defined(__e2k__) || \
@ -346,6 +348,8 @@
# define CURL_FORMAT_CURL_OFF_TU "lu"
# define CURL_SUFFIX_CURL_OFF_T L
# define CURL_SUFFIX_CURL_OFF_TU UL
# define CURL_POPCOUNT64(x) __builtin_popcountl(x)
# define CURL_CTZ64(x) __builtin_ctzl(x)
# endif
# define CURL_TYPEOF_CURL_SOCKLEN_T socklen_t
# define CURL_PULL_SYS_TYPES_H 1