build: avoid overriding system symbols for socket functions#18503
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build: avoid overriding system symbols for socket functions#18503vszakats wants to merge 8 commits into
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Following `accept`. These function have a small amount of calls in the code, and it seems sensible to override them cleanly via macros in the curl namespace. This plays well with all build configurations and with any ways these functions may be implemented, e.g. via macro. Follow-up to 9863599 curl#18502
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By introducing wrappers for them in the curlx namespace: `curlx_fopen()`, `curlx_fdopen()`, `curlx_fclose()`. The undefine/redefine/`(function)()` methods broke on systems implementing these functions as macros. E.g. AIX 32-bit's `fopen()`. Also: - rename `lib/fopen.*` to `lib/curl_fopen.*` (for `Curl_fopen()`) to make room for the newly added `curlx/fopen.h`. - curlx: move file-related functions from `multibyte.c` to `fopen.c`. - tests/server: stop using the curl-specific `fopen()` implementation on Windows. Unicode isn't used by runtests, and it isn't critical to run tests on longs path. It can be re-enabled if this becomes necessary, or if the wrapper receives a feature that's critical for test servers. Reported-by: Andrew Kirillov Bug: #18510 (comment) Follow-up to bf7375e #18503 Follow-up to 9863599 #18502 Follow-up to 3bb5e58 #17827 Closes #18634
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Replace them by `curlx_open()` and `curlx_stat()`. To make it obvious in the source code what is being executed. Also: - tests/server: stop overriding `open()` for test servers. This is critical for the call made from the signal handler. For other calls, it's an option to use `curlx_open()`, but doesn't look important enough to do it, following the path taken with `fopen()`. Follow-up to 10bac43 #18774 Follow-up to 20142f5 #18634 Follow-up to bf7375e #18503 Closes #18776
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Before this patch curl used the C preprocessor to override standard memory allocation symbols: malloc, calloc, strdup, realloc, free. The goal of these is to replace them with curl's debug wrappers in `CURLDEBUG` builds, another was to replace them with the wrappers calling user-defined allocators in libcurl. This solution needed a bunch of workarounds to avoid breaking external headers: it relied on include order to do the overriding last. For "unity" builds it needed to reset overrides before external includes. Also in test apps, which are always built as single source files. It also needed the `(symbol)` trick to avoid overrides in some places. This would still not fix cases where the standard symbols were macros. It was also fragile and difficult to figure out which was the actual function behind an alloc or free call in a specific piece of code. This in turn caused bugs where the wrong allocator was accidentally called. To avoid these problems, this patch replaces this solution with `curlx_`-prefixed allocator macros, and mapping them _once_ to either the libcurl wrappers, the debug wrappers or the standard ones, matching the rest of the code in libtests. This concludes the long journey to avoid redefining standard functions in the curl codebase. Note: I did not update `packages/OS400/*.c` sources. They did not `#include` `curl_setup.h`, `curl_memory.h` or `memdebug.h`, meaning the overrides were never applied to them. This may or may not have been correct. For now I suppressed the direct use of standard allocators via a local `.checksrc`. Probably they (except for `curlcl.c`) should be updated to include `curl_setup.h` and use the `curlx_` macros. This patch changes mappings in two places: - `lib/curl_threads.c` in libtests: Before this patch it mapped to libcurl allocators. After, it maps to standard allocators, like the rest of libtests code. - `units`: before this patch it mapped to standard allocators. After, it maps to libcurl allocators. Also: - drop all position-dependent `curl_memory.h` and `memdebug.h` includes, and delete the now unnecessary headers. - rename `Curl_tcsdup` macro to `curlx_tcsdup` and define like the other allocators. - map `curlx_strdup()` to `_strdup()` on Windows (was: `strdup()`). To fix warnings silenced via `_CRT_NONSTDC_NO_DEPRECATE`. - multibyte: map `curlx_convert_*()` to `_strdup()` on Windows (was: `strdup()`). - src: do not reuse the `strdup` name for the local replacement. - lib509: call `_strdup()` on Windows (was: `strdup()`). - test1132: delete test obsoleted by this patch. - CHECKSRC.md: update text for `SNPRINTF`. - checksrc: ban standard allocator symbols. Follow-up to b12da22 #18866 Follow-up to db98daa #18844 Follow-up to 4deea93 #18814 Follow-up to 9678ff5 #18776 Follow-up to 10bac43 #18774 Follow-up to 20142f5 #18634 Follow-up to bf7375e #18503 Follow-up to 9863599 #18502 Follow-up to 3bb5e58 #17827 Closes #19626
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They were masked by `()`, which was also not necessary anymore. Follow-up to a585cc3 curl#20097 Follow-up to bf7375e curl#18503
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Before this patch
accept4(),socket(),socketpair(),send()andrecv()system symbols were remapped via macros, using the same name,to local curl debug wrappers. This patch replaces these overrides by
introducing curl-namespaced macros that map either to the system symbols
or to their curl debug wrappers in
CURLDEBUG(TrackMemory) builds.This follows a patch that implemented the same for
accept().The old method required tricks to make these redefines work in unity
builds, and avoid them interfering with system headers. These tricks
did not work for system symbols implemented as macros.
The new method allows to setup these mappings once, without interfering
with system headers, upstream macros, or unity builds. It makes builds
more robust.
Also:
Follow-up to 9863599 #18502
Follow-up to 3bb5e58 #17827
.checksrcBug: AIX 32 bit build is broken #18510 (comment)
There are more calls to these in the code (than to socket ones). → build: avoid overriding system symbols for fopen functions #18634
sclose()→CURL_SCLOSE()for consistency?