ladybird/Userland/Utilities/uniq.cpp
demostanis 847577bea2 uniq: Improve POSIX compliance
Adds -d, -c, -i, -f and -s options.
It differs a little bit from other implementations,
but it does the trick and corresponds to POSIX's description
2022-09-09 14:11:52 +01:00

115 lines
4.3 KiB
C++

/*
* Copyright (c) 2020, Matthew L. Curry <matthew.curry@gmail.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/CharacterTypes.h>
#include <AK/RefPtr.h>
#include <AK/StringView.h>
#include <LibCore/ArgsParser.h>
#include <LibCore/Stream.h>
#include <LibCore/System.h>
#include <unistd.h>
static ErrorOr<void> write_line_content(StringView line, size_t count, bool duplicates_only, bool print_count, Core::Stream::File& outfile)
{
if (duplicates_only && count <= 1)
return {};
if (print_count)
TRY(outfile.write(String::formatted("{} {}\n", count, line).bytes()));
else
TRY(outfile.write(String::formatted("{}\n", line).bytes()));
return {};
}
static StringView skip(StringView line, unsigned char_skip_count, unsigned field_skip_count)
{
line = line.trim("\n"sv);
if (field_skip_count) {
bool in_field = false;
int field_index = 0;
unsigned current_field = 0;
for (size_t i = 0; i < line.length(); i++) {
char c = line[i];
if (is_ascii_space(c)) {
in_field = false;
field_index = i;
if (++current_field > field_skip_count)
break;
} else if (!in_field) {
in_field = true;
}
}
line = line.substring_view(field_index);
}
char_skip_count = min(char_skip_count, line.length());
return line.substring_view(char_skip_count);
}
ErrorOr<int> serenity_main(Main::Arguments arguments)
{
TRY(Core::System::pledge("stdio rpath wpath cpath"));
StringView inpath;
StringView outpath;
bool duplicates_only = false;
bool unique_only = false;
bool ignore_case = false;
bool print_count = false;
unsigned skip_chars = 0;
unsigned skip_fields = 0;
Core::ArgsParser args_parser;
args_parser.add_option(duplicates_only, "Only print duplicated lines", "repeated", 'd');
args_parser.add_option(unique_only, "Only print unique lines (default)", "unique", 'u');
args_parser.add_option(ignore_case, "Ignore case when comparing lines", "ignore-case", 'i');
args_parser.add_option(print_count, "Prefix each line by its number of occurrences", "count", 'c');
args_parser.add_option(skip_chars, "Skip N chars", "skip-chars", 's', "N");
args_parser.add_option(skip_fields, "Skip N fields", "skip-fields", 'f', "N");
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(arguments);
if (!unique_only && !duplicates_only) {
unique_only = true;
} else if (unique_only && duplicates_only) {
// Printing duplicated and unique lines shouldn't print anything
return 0;
}
auto infile = TRY(Core::Stream::BufferedFile::create(TRY(Core::Stream::File::open_file_or_standard_stream(inpath, Core::Stream::OpenMode::Read))));
auto outfile = TRY(Core::Stream::File::open_file_or_standard_stream(outpath, Core::Stream::OpenMode::Write));
size_t count = 0;
ByteBuffer previous_buf = TRY(ByteBuffer::create_uninitialized(1024));
ByteBuffer current_buf = TRY(ByteBuffer::create_uninitialized(1024));
StringView previous = TRY(infile->read_line(previous_buf));
StringView previous_to_compare = skip(previous, skip_chars, skip_fields);
while (TRY(infile->can_read_line())) {
// FIXME: The buffer does not automatically resize,
// and this will return EMSGSIZE if the read line
// is more than 1024 bytes.
StringView current = TRY(infile->read_line(current_buf));
StringView current_to_compare = skip(current, skip_chars, skip_fields);
bool lines_equal = ignore_case ? current_to_compare.equals_ignoring_case(previous_to_compare) : current_to_compare == previous_to_compare;
if (!lines_equal) {
TRY(write_line_content(previous, count, duplicates_only, print_count, *outfile));
count = 1;
} else {
count++;
}
swap(current_to_compare, previous_to_compare);
swap(current_buf, previous_buf);
swap(current, previous);
}
TRY(write_line_content(previous, count, duplicates_only, print_count, *outfile));
return 0;
}