ladybird/Userland/cut.cpp
2020-07-03 19:30:13 +02:00

249 lines
8.5 KiB
C++

/*
* Copyright (c) 2019-2020, Marios Prokopakis <mariosprokopakis@gmail.com>
* 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 <AK/QuickSort.h>
#include <AK/StdLibExtras.h>
#include <AK/String.h>
#include <AK/Vector.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
struct Index {
enum class Type {
SingleIndex,
SliceIndex,
RangedIndex
};
ssize_t m_from { -1 };
ssize_t m_to { -1 };
Type m_type { Type::SingleIndex };
bool intersects(const Index& other)
{
if (m_type != Type::RangedIndex)
return m_from == other.m_from;
return !(other.m_from > m_to || other.m_to < m_from);
}
};
static void print_usage_and_exit(int ret)
{
printf("Usage: cut -b list [File]\n");
exit(ret);
}
static void add_if_not_exists(Vector<Index>& indexes, Index data)
{
bool append_to_vector = true;
for (auto& index : indexes) {
if (index.intersects(data)) {
if (index.m_type == Index::Type::RangedIndex) {
index.m_from = AK::min(index.m_from, data.m_from);
index.m_to = AK::max(index.m_to, data.m_to);
}
append_to_vector = false;
}
}
if (append_to_vector) {
indexes.append(data);
}
}
static void expand_list(Vector<String>& tokens, Vector<Index>& indexes)
{
for (auto& token : tokens) {
if (token.length() == 0) {
fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
print_usage_and_exit(1);
}
if (token == "-") {
fprintf(stderr, "cut: invalid range with no endpoint: %s\n", token.characters());
print_usage_and_exit(1);
}
if (token[0] == '-') {
auto index = token.substring(1, token.length() - 1).to_int();
if (!index.has_value()) {
fprintf(stderr, "cut: invalid byte/character position '%s'\n", token.characters());
print_usage_and_exit(1);
}
if (index.value() == 0) {
fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
print_usage_and_exit(1);
}
Index tmp = { 1, index.value(), Index::Type::RangedIndex };
add_if_not_exists(indexes, tmp);
} else if (token[token.length() - 1] == '-') {
auto index = token.substring(0, token.length() - 1).to_int();
if (!index.has_value()) {
fprintf(stderr, "cut: invalid byte/character position '%s'\n", token.characters());
print_usage_and_exit(1);
}
if (index.value() == 0) {
fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
print_usage_and_exit(1);
}
Index tmp = { index.value(), -1, Index::Type::SliceIndex };
add_if_not_exists(indexes, tmp);
} else {
auto range = token.split('-');
if (range.size() == 2) {
auto index1 = range[0].to_int();
if (!index1.has_value()) {
fprintf(stderr, "cut: invalid byte/character position '%s'\n", range[0].characters());
print_usage_and_exit(1);
}
auto index2 = range[1].to_int();
if (!index2.has_value()) {
fprintf(stderr, "cut: invalid byte/character position '%s'\n", range[1].characters());
print_usage_and_exit(1);
}
if (index1.value() > index2.value()) {
fprintf(stderr, "cut: invalid decreasing range\n");
print_usage_and_exit(1);
} else if (index1.value() == 0 || index2.value() == 0) {
fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
print_usage_and_exit(1);
}
Index tmp = { index1.value(), index2.value(), Index::Type::RangedIndex };
add_if_not_exists(indexes, tmp);
} else if (range.size() == 1) {
auto index = range[0].to_int();
if (!index.has_value()) {
fprintf(stderr, "cut: invalid byte/character position '%s'\n", range[0].characters());
print_usage_and_exit(1);
}
if (index.value() == 0) {
fprintf(stderr, "cut: byte/character positions are numbered from 1\n");
print_usage_and_exit(1);
}
Index tmp = { index.value(), index.value(), Index::Type::SingleIndex };
add_if_not_exists(indexes, tmp);
} else {
fprintf(stderr, "cut: invalid byte or character range\n");
print_usage_and_exit(1);
}
}
}
}
static void cut_file(const String& file, const Vector<Index>& byte_vector)
{
FILE* fp = stdin;
if (!file.is_null()) {
fp = fopen(file.characters(), "r");
if (!fp) {
fprintf(stderr, "cut: Could not open file '%s'\n", file.characters());
return;
}
}
char* line = nullptr;
ssize_t line_length = 0;
size_t line_capacity = 0;
while ((line_length = getline(&line, &line_capacity, fp)) != -1) {
line[line_length - 1] = '\0';
line_length--;
for (auto& i : byte_vector) {
if (i.m_type == Index::Type::SliceIndex && i.m_from < line_length)
printf("%s", line + i.m_from - 1);
else if (i.m_type == Index::Type::SingleIndex && i.m_from <= line_length)
printf("%c", line[i.m_from - 1]);
else if (i.m_type == Index::Type::RangedIndex && i.m_from <= line_length) {
auto to = i.m_to > line_length ? line_length : i.m_to;
auto sub_string = String(line).substring(i.m_from - 1, to - i.m_from + 1);
printf("%s", sub_string.characters());
} else
break;
}
printf("\n");
}
if (line)
free(line);
if (!file.is_null())
fclose(fp);
}
int main(int argc, char** argv)
{
String byte_list = "";
Vector<String> tokens;
Vector<String> files;
if (argc == 1) {
print_usage_and_exit(1);
}
for (int i = 1; i < argc;) {
if (!strcmp(argv[i], "-b")) {
/* The next argument should be a list of bytes. */
byte_list = (i + 1 < argc) ? argv[i + 1] : "";
if (byte_list == "") {
print_usage_and_exit(1);
}
tokens = byte_list.split(',');
i += 2;
} else if (!strcmp(argv[i], "--help") || !strcmp(argv[i], "-h")) {
print_usage_and_exit(1);
} else if (argv[i][0] != '-') {
files.append(argv[i++]);
} else {
fprintf(stderr, "cut: invalid argument %s\n", argv[i]);
print_usage_and_exit(1);
}
}
if (byte_list == "")
print_usage_and_exit(1);
Vector<Index> byte_vector;
expand_list(tokens, byte_vector);
quick_sort(byte_vector, [](auto& a, auto& b) { return a.m_from < b.m_from; });
if (files.is_empty())
files.append(String());
/* Process each file */
for (auto& file : files)
cut_file(file, byte_vector);
return 0;
}