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/*
* Copyright (c) 2018-2021, Andreas Kling <kling@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibCore/ArgsParser.h>
#include <LibCore/System.h>
#include <LibMain/Main.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/stat.h>
#include <unistd.h>
enum TruncateOperation {
OP_Set,
OP_Grow,
OP_Shrink,
};
ErrorOr<int> serenity_main(Main::Arguments arguments)
{
TRY(Core::System::pledge("stdio rpath wpath cpath"));
StringView resize;
StringView reference;
StringView file;
Core::ArgsParser args_parser;
args_parser.add_option(resize, "Resize the target file to (or by) this size. Prefix with + or - to expand or shrink the file, or a bare number to set the size exactly", "size", 's', "size");
args_parser.add_option(reference, "Resize the target file to match the size of this one", "reference", 'r', "file");
args_parser.add_positional_argument(file, "File path", "file");
args_parser.parse(arguments);
if (resize.is_empty() && reference.is_empty()) {
args_parser.print_usage(stderr, arguments.argv[0]);
return 1;
}
if (!resize.is_empty() && !reference.is_empty()) {
args_parser.print_usage(stderr, arguments.argv[0]);
return 1;
}
auto op = OP_Set;
off_t size = 0;
if (!resize.is_empty()) {
String str = resize;
switch (str[0]) {
case '+':
op = OP_Grow;
str = str.substring(1, str.length() - 1);
break;
case '-':
op = OP_Shrink;
str = str.substring(1, str.length() - 1);
break;
}
auto size_opt = str.to_int<off_t>();
if (!size_opt.has_value()) {
args_parser.print_usage(stderr, arguments.argv[0]);
return 1;
}
size = size_opt.value();
}
if (!reference.is_empty()) {
auto stat = TRY(Core::System::stat(reference));
size = stat.st_size;
}
auto fd = TRY(Core::System::open(file, O_RDWR | O_CREAT, 0666));
auto stat = TRY(Core::System::fstat(fd));
switch (op) {
case OP_Set:
break;
case OP_Grow:
size = stat.st_size + size;
break;
case OP_Shrink:
size = stat.st_size - size;
break;
}
TRY(Core::System::ftruncate(fd, size));
TRY(Core::System::close(fd));
return 0;
}
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