diff --git a/Userland/uniq.cpp b/Userland/uniq.cpp new file mode 100644 index 0000000000..0034c1cb62 --- /dev/null +++ b/Userland/uniq.cpp @@ -0,0 +1,100 @@ +/* + * Copyright (c) 2020, Matthew L. Curry + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, this + * list of conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright notice, + * this list of conditions and the following disclaimer in the documentation + * and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" + * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE + * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE + * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE + * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL + * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER + * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, + * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +#include +#include +#include +#include +#include +#include + +struct linebuf { + char* buf = NULL; + size_t len = 0; +}; + +static FILE* get_stream(const char* filepath, const char* perms) +{ + FILE* ret; + + if (filepath == nullptr) { + if (perms[0] == 'r') + return stdin; + return stdout; + } + + ret = fopen(filepath, perms); + if (ret == nullptr) { + perror("fopen"); + exit(1); + } + + return ret; +} + +int main(int argc, char** argv) +{ + if (pledge("stdio rpath wpath cpath", nullptr) > 0) { + perror("pledge"); + return 1; + } + + const char* inpath = nullptr; + const char* outpath = nullptr; + Core::ArgsParser args_parser; + args_parser.add_positional_argument(inpath, "Input file", "input", Core::ArgsParser::Required::No); + args_parser.add_positional_argument(outpath, "Output file", "output", Core::ArgsParser::Required::No); + args_parser.parse(argc, argv); + + FILE* infile = get_stream(inpath, "r"); + FILE* outfile = get_stream(outpath, "w"); + + struct linebuf buffers[2]; + struct linebuf* previous = &(buffers[0]); + struct linebuf* current = &(buffers[1]); + bool first_run = true; + for (;;) { + errno = 0; + ssize_t rc = getline(&(current->buf), &(current->len), infile); + if (rc < 0 && errno != 0) { + perror("getline"); + exit(1); + } + if (rc < 0) + break; + if (!first_run && strcmp(current->buf, previous->buf) == 0) + continue; + + fputs(current->buf, outfile); + AK::swap(current, previous); + first_run = false; + } + + fclose(infile); + fclose(outfile); + + return 0; +}