init: initial commit

.clang-format

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+ColumnLimit: 0
+PointerAlignment: Left

.github/dependabot.yaml

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+version: 2
+updates:
+  - package-ecosystem: github-actions
+    directory: "/"
+    schedule:
+      interval: "weekly"

.github/workflows/ci.yaml

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+name: ci
+
+on: [pull_request, push]
+
+jobs:
+  check:
+    runs-on: macos-15
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: build
+        run: make CC=$(brew --prefix llvm@18)/bin/clang
+
+      - name: run
+        run: |
+          touch x
+          bin/can x
+          if [[ -f x ]]; then
+            exit 1
+          fi
+

.gitignore

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+# General.
+.DS_Store
+bin/
+
+# Prerequisites
+*.d
+
+# Object files
+*.o
+*.ko
+*.obj
+*.elf
+
+# Linker output
+*.ilk
+*.map
+*.exp
+
+# Precompiled Headers
+*.gch
+*.pch
+
+# Libraries
+*.lib
+*.a
+*.la
+*.lo
+
+# Shared objects (inc. Windows DLLs)
+*.dll
+*.so
+*.so.*
+*.dylib
+
+# Executables
+*.exe
+*.out
+*.app
+*.i*86
+*.x86_64
+*.hex
+
+# Debug files
+*.dSYM/
+*.su
+*.idb
+*.pdb
+
+# Kernel Module Compile Results
+*.mod*
+*.cmd
+.tmp_versions/
+modules.order
+Module.symvers
+Mkfile.old
+dkms.conf

LICENCE

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+ISC License
+
+Copyright (c) 2023 Tshaka Lekholoane
+
+Permission to use, copy, modify, and/or distribute this software for any
+purpose with or without fee is hereby granted, provided that the above
+copyright notice and this permission notice appear in all copies.
+
+THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
+REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT,
+INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR
+OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+PERFORMANCE OF THIS SOFTWARE.

Makefile

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+COMMIT = $(shell git rev-parse --short HEAD)
+DATE   = $(shell date -u +"%Y.%m.%d")
+BUILD  = $(shell printf "%s (%s)" "$(DATE)" "$(COMMIT)" )
+CC     = cc
+CFLAGS = -DCAN_BUILD="\"$(BUILD)\"" -O3 -Wall -Wextra -Wno-c++98-compat \
+	-Wno-cast-function-type-strict -Wno-declaration-after-statement \
+	-Wno-format-nonliteral -Wno-incompatible-pointer-types-discards-qualifiers \
+	-Wno-poison-system-directories -Wno-vla -framework Foundation -march=native \
+	-pedantic -std=c23
+
+bin/can: src/main.o
+	mkdir -p bin
+	$(CC) $(CFLAGS) src/main.o -o bin/can
+
+src/main.o:
+
+.PHONY: clean
+clean:
+	-rm bin/can src/main.o

README.md

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+# `can`
+
+![Continuous Integration](https://github.com/tshakalekholoane/can/actions/workflows/ci.yaml/badge.svg)
+
+`can` is a macOS command-line utility that provides an alternative to the `rm` command. Instead of permanently deleting files and directories, `can` moves them to the user's Trash, allowing for easy recovery if needed.
+
+## Usage
+
+```
+usage: can [-h | -V] [--] file ...
+```
+
+## Installation
+
+### Source
+
+The application can be built from source by cloning the repository and running the following commands which require working versions of [Make](https://www.gnu.org/software/make/) and a C compiler with C23 support.
+
+> [!WARNING]
+> GCC 14 incorrectly uses `__STDC_VERSION__ == 202000` for C23 [^1], which will produce an error even when the `-std=c23` flag is set.
+
+```shell
+git clone https://github.com/tshakalekholoane/can && cd can
+make
+```
+
+[^1]: See https://stackoverflow.com/a/78582932.

src/main.c

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+#ifndef __APPLE__
+#error "This program is intended to only run on macOS."
+#endif
+
+#if __STDC_VERSION__ < 202000
+#error "This code requires C23 or later."
+#endif
+
+#include <errno.h>
+#include <getopt.h>
+#include <objc/message.h>
+#include <pwd.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+
+#ifndef CAN_BUILD
+#define CAN_BUILD "TIP"
+#endif
+
+#define shift(n) \
+  do {           \
+    argc -= (n); \
+    argv += (n); \
+  } while (false)
+
+#define unlikely(c) __builtin_expect(!!(c), false)
+
+static const char* usage = "usage: can [-h | -V] [--] file ...";
+
+// Objective-C messaging primitives require that functions be cast to an
+// appropriate function pointer type before being called [1].
+//
+// [1]: https://tshaka.dev/a/7hq9i9
+
+static id file_manager_default_manager(void) {
+  auto file_manager = objc_getClass("NSFileManager");
+  typedef id (*send_type)(Class, SEL);
+  auto func = (send_type)objc_msgSend;
+  return func(file_manager, sel_registerName("defaultManager"));
+}
+
+static id file_manager_string_with_file_system_representation(id self, const char string[static 1]) {
+  typedef id (*send_type)(id, SEL, const char*, unsigned long);
+  auto func = (send_type)objc_msgSend;
+  return func(self, sel_registerName("stringWithFileSystemRepresentation:length:"), string, strlen(string));
+}
+
+static bool file_manager_trash_item_at_url(id self, id url, id* err) {
+  typedef bool (*send_type)(id, SEL, id, id, id*);
+  auto func = (send_type)objc_msgSend;
+  return func(self, sel_registerName("trashItemAtURL:resultingItemURL:error:"), url, nullptr, err);
+}
+
+static id error_localized_description(id self) {
+  typedef id (*send_type)(id, SEL);
+  auto func = (send_type)objc_msgSend;
+  return func(self, sel_registerName("localizedDescription"));
+}
+
+static const char* string_utf8_string(id self) {
+  typedef const char* (*send_type)(id, SEL);
+  auto func = (send_type)objc_msgSend;
+  return func(self, sel_registerName("UTF8String"));
+}
+
+static id url_file_url_with_path(id string) {
+  auto url = objc_getClass("NSURL");
+  typedef id (*send_type)(Class, SEL, id);
+  auto func = (send_type)objc_msgSend;
+  return func(url, sel_registerName("fileURLWithPath:"), string);
+}
+
+int main(int argc, char* argv[argc + 1]) {
+  int opt;
+  while ((opt = getopt(argc, argv, "hV")) != -1) {
+    switch (opt) {
+    case 'h':
+      printf("%s\n", usage);
+      return EXIT_SUCCESS;
+    case 'V':
+      printf("can %s\n", CAN_BUILD);
+      return EXIT_SUCCESS;
+    default:
+      fprintf(stderr, "%s\n", usage);
+      return EXIT_FAILURE;
+    }
+  }
+  if (unlikely(argc == 1)) {
+    fprintf(stderr, "%s\n", usage);
+    return EXIT_FAILURE;
+  }
+  shift(1);
+
+  for (ssize_t i = 0; i < (ssize_t)argc; i++) {
+    auto name = argv[i];
+    if (unlikely(strcmp(name, ".") == 0 || strcmp(name, "..") == 0 || strcmp(name, "/") == 0)) {
+      fprintf(stderr, "\"/\", \".\", and \"..\" may not be removed.\n");
+      return EXIT_FAILURE;
+    }
+  }
+
+  // Avoid using the root user's trash when invoked with sudo.
+  auto superuser = getenv("SUDO_USER");
+  if (unlikely(superuser != nullptr)) {
+    auto entry = getpwnam(superuser);
+    if (unlikely(!entry || seteuid(entry->pw_uid))) {
+      fprintf(stderr, "%s\n", strerror(errno));
+      return EXIT_FAILURE;
+    }
+  }
+
+  // Ignore flag separator.
+  if (unlikely(strcmp(argv[0], "--") == 0))
+    shift(1);
+
+  auto exit_code = EXIT_SUCCESS;
+  auto file_manager = file_manager_default_manager();
+  for (ssize_t i = 0; i < (ssize_t)argc; i++) {
+    auto path = file_manager_string_with_file_system_representation(file_manager, argv[i]);
+    auto url = url_file_url_with_path(path);
+    id err;
+    if (unlikely(!file_manager_trash_item_at_url(file_manager, url, &err))) {
+      auto description = error_localized_description(err);
+      fprintf(stderr, "%s\n", string_utf8_string(description));
+      exit_code = EXIT_FAILURE;
+    }
+  }
+  return exit_code;
+}