A command line tool and library for transferring data with URL syntax, supporting DICT, FILE, FTP, FTPS, GOPHER, GOPHERS, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, MQTT, POP3, POP3S, RTMP, RTMPS, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET, TFTP, WS and WSS. libcurl offers a myriad of powerful features
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Viktor Szakats 193cb00ce9
build: stop overriding standard memory allocation functions
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 b12da22db1 #18866
Follow-up to db98daab05 #18844
Follow-up to 4deea9396b #18814
Follow-up to 9678ff5b1b #18776
Follow-up to 10bac43b87 #18774
Follow-up to 20142f5d06 #18634
Follow-up to bf7375ecc5 #18503
Follow-up to 9863599d69 #18502
Follow-up to 3bb5e58c10 #17827

Closes #19626
2025-11-28 10:44:26 +01:00
.circleci runtests: detect bad libssh differently for test 1459 (fixing CircleCI libssh job) 2025-11-16 23:28:44 +01:00
.github GHA/linux-old: add support for using custom CMake versions 2025-11-28 03:11:33 +01:00
CMake cmake: add support for libbacktrace, fix two build issues 2025-11-24 14:29:29 +01:00
docs build: stop overriding standard memory allocation functions 2025-11-28 10:44:26 +01:00
include build: add build-level CURL_DISABLE_TYPECHECK options 2025-11-21 13:48:35 +01:00
lib build: stop overriding standard memory allocation functions 2025-11-28 10:44:26 +01:00
LICENSES krb5: drop support for Kerberos FTP 2025-09-20 23:58:28 +02:00
m4 autotools: add nettle library detection via pkg-config (for GnuTLS) 2025-11-26 12:39:30 +01:00
packages build: stop overriding standard memory allocation functions 2025-11-28 10:44:26 +01:00
plan9 tidy-up: LibreSSL Git repository URLs and local CI builds 2025-10-01 12:55:20 +02:00
projects projects/README.md: Markdown fixes 2025-11-17 15:09:09 +01:00
scripts build: stop overriding standard memory allocation functions 2025-11-28 10:44:26 +01:00
src build: stop overriding standard memory allocation functions 2025-11-28 10:44:26 +01:00
tests build: stop overriding standard memory allocation functions 2025-11-28 10:44:26 +01:00
.dir-locals.el copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
.editorconfig .editorconfig: add 2025-09-02 08:36:40 +02:00
.git-blame-ignore-revs copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
.gitattributes winbuild: MS-DOS batch tidy-ups 2024-07-02 19:26:15 +02:00
.gitignore build: drop the winbuild build system 2025-09-20 01:20:25 +02:00
.mailmap REUSE: add copyright header to two files 2025-11-03 16:08:52 +01:00
acinclude.m4 badwords: add more contractions, fix fallouts 2025-11-17 19:29:15 +01:00
appveyor.sh appveyor: add support for using custom CMake versions 2025-11-28 00:51:08 +01:00
appveyor.yml appveyor: add support for using custom CMake versions 2025-11-28 00:51:08 +01:00
buildconf copyright: update all copyright lines and remove year ranges 2023-01-03 09:19:21 +01:00
CHANGES.md CHANGES: rename to CHANGES.md, no longer generated 2024-08-01 13:37:12 +02:00
CMakeLists.txt cmake: add support for libbacktrace, fix two build issues 2025-11-24 14:29:29 +01:00
configure.ac memdebug: produce stack trace dump with libbacktrace 2025-11-24 11:58:18 +01:00
COPYING COPYING: bump copyright year range to 1996 - 2025 2025-01-01 21:12:12 +01:00
curl-config.in curl-config: remove X prefix use 2025-08-04 10:01:07 +02:00
Dockerfile Dockerfile: update debian:bookworm-slim digest to 936abff 2025-11-05 15:24:21 +01:00
GIT-INFO.md REUSE: add copyright header to two files 2025-11-03 16:08:52 +01:00
libcurl.pc.in configure: do not echo most inherited LDFLAGS to config files 2024-11-14 09:55:45 +01:00
Makefile.am cmake: add support for libbacktrace, fix two build issues 2025-11-24 14:29:29 +01:00
README krb5: drop support for Kerberos FTP 2025-09-20 23:58:28 +02:00
README.md badwords: re-sync with curl-www, fix issues found 2025-11-12 00:53:44 +01:00
RELEASE-NOTES RELEASE-NOTES: synced 2025-11-27 16:14:37 +01:00
renovate.json renovate.json: replace CI: prefix with GHA: 2025-11-17 16:50:20 +01:00
REUSE.toml tests/data: add %includetext, dedupe XML payloads into external file 2025-11-13 12:24:50 +01:00
SECURITY.md docs: Clarify OpenSSF Best Practices vs Scorecard 2024-08-22 11:50:20 +02:00

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curl is a command-line tool for transferring data from or to a server using URLs. It supports these protocols: DICT, FILE, FTP, FTPS, GOPHER, GOPHERS, HTTP, HTTPS, IMAP, IMAPS, LDAP, LDAPS, MQTT, POP3, POP3S, RTMP, RTMPS, RTSP, SCP, SFTP, SMB, SMBS, SMTP, SMTPS, TELNET, TFTP, WS and WSS.

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