After this patch, the codebase no longer overrides system printf
functions. Instead it explicitly calls either the curl printf functions
`curl_m*printf()` or the system ones using their original names.
Also:
- drop unused `curl_printf.h` includes.
- checksrc: ban system printf functions, allow where necessary.
Follow-up to db98daab05#18844
Follow-up to 4deea9396b#18814Closes#18866
`-Weverything` is not enabled by curl, and not recommended by LLVM,
because it may enable experimental options, and will result in new
fallouts after toolchain upgrades. This patch aims to fix/silence as much
as possible as found with llvm/clang 21.1.0. It also permanently enables
warnings that were fixed in source and deemed manageable in the future.
`-Wformat` warnings are addressed separately via #18343.
Fix/silence warnings in the source:
- typecheck-gcc.h: fix `-Wreserved-identifier`.
- lib: silence `-Wcast-function-type-strict`.
For llvm 16+ or Apple clang 16+.
- asyn-ares: limit `HAPPY_EYEBALLS_DNS_TIMEOUT` to old c-ares versions.
- curl_trc: fix `-Wc++-hidden-decl`.
- doh: fix `-Wc++-keyword`.
- ftp: fix `-Wreserved-identifier`.
- ldap: fix `-Wreserved-identifier`.
- mqtt: comment unused macro to avoid warning.
- multi_ev: drop unused macros to avoid warnings.
- setopt: fix useless `break;` after `return;`.
- gtls, mbedtls, rustls: silence `-Wconditional-uninitialized`.
- socks_sspi, schannel, x509asn1: fix `-Wimplicit-int-enum-cast`.
- x509asn1: fix `-Wc++-keyword`.
- openssl: scope `OSSL_UI_METHOD_CAST` to avoid unused macro warning.
- libssh2, wolfssl: drop unused macros.
- curl_ngtcp2, curl_quiche, httpsrr, urlapi: drop/limit unused macros.
- tool_getparam: fix useless `break;` after `return;` or `break;`.
Not normally enabled because it doesn't work with unity.
https://github.com/llvm/llvm-project/issues/71046
- tool_operate: fix `-Wc++-keyword`.
- curlinfo: fix a `-Wunsafe-buffer-usage`.
- tests: silence `-Wformat-non-iso`.
- lib557: fix `-Wreserved-identifier`.
- lib1565: silence `-Wconditional-uninitialized`.
Enable the above clang warnings permanently in picky mode:
- `-Wc++-hidden-decl`
- `-Wc++-keyword` (except for Windows, where it collides with `wchar_t`)
- `-Wcast-function-type-strict`
- `-Wcast-function-type`
- `-Wconditional-uninitialized`
- `-Wformat-non-iso` (except for clang-cl)
- `-Wreserved-identifier`
- `-Wtentative-definition-compat`
Silence problematic `-Weverything` warnings globally (in picky mode):
- `-Wused-but-marked-unused` (88000+ hits) and
`-Wdisabled-macro-expansion` (2600+ hits).
Triggered by `typecheck-gcc.h` when building with clang 14+.
Maybe there exists a way to fix within that header?
Ref: https://discourse.llvm.org/t/removing-wused-but-marked-unused/55310
- `-Wunsafe-buffer-usage`. clang 16+. 7000+ hits.
May be useful in theory, but such high volume of hits makes it
impractical to review and possibly address. Meant for C++.
Ref: https://clang.llvm.org/docs/SafeBuffers.html
Ref: https://stackoverflow.com/questions/77017567/how-to-fix-code-to-avoid-warning-wunsafe-buffer-usage
Ref: https://discourse.llvm.org/t/rfc-c-buffer-hardening/65734
Ref: https://github.com/llvm/llvm-project/pull/111624
- `-Wimplicit-void-ptr-cast`. clang 21+. 1700+ hits.
C++ warning, deemed pure noise.
Ref: https://github.com/curl/curl/issues/18470#issuecomment-3253506266
- `-Wswitch-default` (180+ hits), `-Wswitch-enum` (190+ hits),
`-Wcovered-switch-default` (20+ hits).
Next to impossible to fix cleanly, esp. when the covered `case`
branches depend on compile-time options.
- `-Wdocumentation-unknown-command` (8+ hits).
Triggered in a few sources. Seems arbitrary and bogus.
- `-Wpadded` (550+ hits).
- `-Wc++-keyword` on Windows, where it collides with `wchar_t`.
(100+ hits)
Ref: https://github.com/llvm/llvm-project/issues/155988
- `-Wreserved-macro-identifier`. clang 13+. 5+ hits.
Sometimes it's necessary to set external macros that use
the reserved namespace. E.g. `_CRT_NONSTDC_NO_DEPRECATE`,
`__ENVIRONMENT_MAC_OS_X_VERSION_MIN_REQUIRED__`, `__NO_NET_API`,
possibly `_REENTRANT`, and more.
It's not worth trying to silence them individually.
- `-Wnonportable-system-include-path` with `clang-cl`.
It'd be broken by doing what the warning suggests.
- `-Wformat-non-iso` for clang-cl.
CMake `PICKY_COMPILER=ON` (the default) or `./configure`
`--enable-warnings` (not the default) is required to enable these
silencing rules.
Also:
- autotools, cmake: fix Apple clang and mainline llvm version translations.
Ref: https://en.wikipedia.org/wiki/Xcode#Toolchain_versions
- autotools, cmake: enable `-Warray-compare` for clang 20+.
Follow-up to 4b7accda5a#17196
- cmake: fix to enable `-Wmissing-variable-declarations` at an earlier
clang version.
- cmake: update internal logic to handle warning options with `+` in
them.
- cmake: fix internal logic to match the whole option when looking
into `CMAKE_C_FLAGS` for custom-disabled warnings.
Follow-up to b85cb8cb4e#18485Closes#18477
`getsock()` calls operated on a global limit that could
not be configure beyond 16 sockets. This is no longer adequate
with the new happy eyeballing strategy.
Instead, do the following:
- make `struct easy_pollset` dynamic. Starting with
a minimal room for two sockets, the very common case,
allow it to grow on demand.
- replace all protocol handler getsock() calls with pollsets
and a CURLcode to return failures
- add CURLcode return for all connection filter `adjust_pollset()`
callbacks, since they too can now fail.
- use appropriately in multi.c and multi_ev.c
- fix unit2600 to trigger pollset growth
Closes#18164
When a socket is closed, only inform the application
socket callback about it if the socket had been announced
before to the callback.
Reported-by: yaoy6 on github
Fixes#17949Closes#17950
Add a bitset `dirty` to the multi handle. The presence of a transfer int
he "dirty" set means: this transfer has something to do ASAP.
"dirty" is set by multiplexing protocols like HTTP/2 and 3 when
encountering response data for another transfer than the current one.
"dirty" is set by protocols that want to be called.
Implementation:
* just an additional `uint_bset` in the multi handle
* `Curl_multi_mark_dirty()` to add a transfer to the dirty set.
* `multi_runsingle()` clears the dirty bit of the transfer at
start. Without new dirty marks, this empties the set after
al dirty transfers have been run.
* `multi_timeout()` immediately gives the current time and
timeout_ms == 0 when dirty transfers are present.
* multi_event: marks all transfers tracked for a socket as dirty.
Then marks all expired transfers as dirty. Then it runs
all dirty transfers.
With this mechanism:
* Most uses of `EXPIRE_RUN_NOW` are replaced by `Curl_multi_mark_dirty()`
* `Curl_multi_mark_dirty()` is cheaper than querying if a transfer is
already dirty or set for timeout. There is no need to check, just do it.
* `data->state.select_bits` is eliminated. We need no longer to
simulate a poll event to make a transfer run.
Closes#17662
Move curlx_ functions into its own subdir.
The idea is to use the curlx_ prefix proper on these functions, and use
these same function names both in tool, lib and test suite source code.
Stop the previous special #define setup for curlx_ names.
The printf defines are now done for the library alone. Tests no longer
use the printf defines. The tool code sets its own defines. The printf
functions are not curlx, they are publicly available.
The strcase defines are not curlx_ functions and should not be used by
tool or server code.
dynbuf, warnless, base64, strparse, timeval, timediff are now proper
curlx functions.
When libcurl is built statically, the functions from the library can be
used as-is. The key is then that the functions must work as-is, without
having to be recompiled for use in tool/tests. This avoids symbol
collisions - when libcurl is built statically, we use those functions
directly when building the tool/tests. When libcurl is shared, we
build/link them separately for the tool/tests.
Assisted-by: Jay Satiro
Closes#17253
With a meta_hash at each connection (similar to easy handle, let
multi_ev.c store its pollsets as meta data, no longer needing its own
hashes.
This eliminates the last use of Curl_hash_offt. Remove it.
Closes#17095
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
When handling connections (not transfers) related events, always use the
passed `conn` and not `data->conn` as the transfer does not need to have
the same connection.
Fix handling of conn pollset diffs to disregard the transfer.
Closes#16782
The issues found fell into these categories, with the applied fixes:
- const was accidentally stripped.
Adjust code to not cast or cast with const.
- const/volatile missing from arguments, local variables.
Constify arguments or variables, adjust/delete casts. Small code
changes in a few places.
- const must be stripped because an API dependency requires it.
Strip `const` with `CURL_UNCONST()` macro to silence the warning out
of our control. These happen at API boundaries. Sometimes they depend
on dependency version, which this patch handles as necessary. Also
enable const support for the zlib API, using `ZLIB_CONST`. Supported
by zlib 1.2.5.2 and newer.
- const must be stripped because a curl API requires it.
Strip `const` with `CURL_UNCONST()` macro to silence the warning out
of our immediate control. For example we promise to send a non-const
argument to a callback, though the data is const internally.
- other cases where we may avoid const stripping by code changes.
Also silenced with `CURL_UNCONST()`.
- there are 3 places where `CURL_UNCONST()` is cast again to const.
To silence this type of warning:
```
lib/vquic/curl_osslq.c:1015:29: error: to be safe all intermediate
pointers in cast from 'unsigned char **' to 'const unsigned char **'
must be 'const' qualified [-Werror=cast-qual]
lib/cf-socket.c:734:32: error: to be safe all intermediate pointers in
cast from 'char **' to 'const char **' must be 'const' qualified
[-Werror=cast-qual]
```
There may be a better solution, but I couldn't find it.
These cases are handled in separate subcommits, but without further
markup.
If you see a `-Wcast-qual` warning in curl, we appreciate your report
about it.
Closes#16142
`data->id` is unique in the same connection pool, but a multi may
involved more than one pool. `data->mid` is unique inside the multi and
since multi_ev lives inside one multi, the `mid` is the right thing to
use.
Closes#16545
Add a standalong hash table for curl_offt_t as key. This allows a
smaller memory footprint and faster lookups as we do not need to deal
with variable key lengths.
Use in all places we had the standard hash for this purpose.
Closes#16442
Rework the event based handling of transfers and connections to
be "localized" into a single source file with clearer dependencies.
- add multi_ev.c and multi_ev.h
- add docs/internal/MULTI-EV.md to explain the overall workings
- only do event handling book keeping when the socket callback
is set
- add handling for "connection only" event tracking, when internal
easy handles are used that are not really tied to a connection.
Used in connection pool.
- remove transfer member "last_poll" and connections "shutdown_poll"
and keep all that internal to multi_ev.c
- add CURL_TRC_M() for tracing of "multi" related things, including
event handling and connection pool operations. Add new trace
feature "multi" for trace config.
multi traces will show exactly what is going on in regard to
event handling.
- multi: trace transfers "mstate" in every CURL_TRC_M() call
- make internal trace buffer 2048 bytes and end the silliness
with +n here -m there. Adjust test 1652 expectations of resulting
length and input edge cases.
- add trace feature "lib-ids" to perfix libcurl traces with transfer
and connection ids. Useful for debugging libcurl applications.
Closes#16308
