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/*
* Copyright (c) 2021, János Tóth <toth-janos@outlook.com>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Optional.h>
#include <AK/String.h>
#include <AK/Vector.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
const char* usage = "usage:\n"
"\tdd <options>\n"
"options:\n"
"\tif=<file>\tinput file (default: stdin)\n"
"\tof=<file>\toutput file (default: stdout)\n"
"\tbs=<size>\tblocks size (default: 512)\n"
"\tcount=<size>\t<size> blocks to copy (default: 0 (until end-of-file))\n"
"\tseek=<size>\tskip <size> blocks at start of output (default: 0)\n"
"\tskip=<size>\tskip <size> blocks at start of input (default: 0)\n"
"\tstatus=<level>\tlevel of output (default: default)\n"
"\t\t\tdefault - error messages + final statistics\n"
"\t\t\tnone - just error messages\n"
"\t\t\tnoxfer - no final statistics\n"
"\t--help\t\tshows this text\n";
enum Status {
Default,
None,
Noxfer
};
static String split_at_equals(const char* argument)
{
String string_value(argument);
auto values = string_value.split('=');
if (values.size() != 2) {
fprintf(stderr, "Unable to parse: %s\n", argument);
return {};
} else {
return values[1];
}
}
static int handle_io_file_arguments(int& fd, int flags, const char* argument)
{
auto value = split_at_equals(argument);
if (value.is_empty()) {
return -1;
}
fd = open(value.characters(), flags);
if (fd == -1) {
fprintf(stderr, "Unable to open: %s\n", value.characters());
return -1;
} else {
return 0;
}
}
static int handle_size_arguments(size_t& numeric_value, const char* argument)
{
auto value = split_at_equals(argument);
if (value.is_empty()) {
return -1;
}
Optional<unsigned> numeric_optional = value.to_uint();
if (!numeric_optional.has_value()) {
fprintf(stderr, "Invalid size-value: %s\n", value.characters());
return -1;
}
numeric_value = numeric_optional.value();
if (numeric_value < 1) {
fprintf(stderr, "Invalid size-value: %lu\n", numeric_value);
return -1;
} else {
return 0;
}
}
static int handle_status_arguments(Status& status, const char* argument)
{
auto value = split_at_equals(argument);
if (value.is_empty()) {
return -1;
}
if (value == "default") {
status = Default;
return 0;
} else if (value == "noxfer") {
status = Noxfer;
return 0;
} else if (value == "none") {
status = None;
return 0;
} else {
fprintf(stderr, "Unknown status: %s\n", value.characters());
return -1;
}
}
int main(int argc, char** argv)
{
int input_fd = 0;
int input_flags = O_RDONLY;
int output_fd = 1;
int output_flags = O_CREAT | O_WRONLY;
size_t block_size = 512;
size_t count = 0;
size_t skip = 0;
size_t seek = 0;
Status status = Default;
size_t total_bytes_copied = 0;
size_t total_blocks_in = 0, partial_blocks_in = 0;
size_t total_blocks_out = 0, partial_blocks_out = 0;
uint8_t* buffer = nullptr;
ssize_t nread = 0, nwritten = 0;
for (int a = 1; a < argc; a++) {
if (!strcmp(argv[a], "--help")) {
printf("%s", usage);
return 0;
} else if (!strncmp(argv[a], "if=", 3)) {
if (handle_io_file_arguments(input_fd, input_flags, argv[a]) < 0) {
return 1;
}
} else if (!strncmp(argv[a], "of=", 3)) {
if (handle_io_file_arguments(output_fd, output_flags, argv[a]) < 0) {
return 1;
}
} else if (!strncmp(argv[a], "bs=", 3)) {
if (handle_size_arguments(block_size, argv[a]) < 0) {
return 1;
}
} else if (!strncmp(argv[a], "count=", 6)) {
if (handle_size_arguments(count, argv[a]) < 0) {
return 1;
}
} else if (!strncmp(argv[a], "seek=", 5)) {
if (handle_size_arguments(seek, argv[a]) < 0) {
return 1;
}
} else if (!strncmp(argv[a], "skip=", 5)) {
if (handle_size_arguments(skip, argv[a]) < 0) {
return 1;
}
} else if (!strncmp(argv[a], "status=", 7)) {
if (handle_status_arguments(status, argv[a]) < 0) {
return 1;
}
} else {
fprintf(stderr, "%s", usage);
return 1;
}
}
if ((buffer = (uint8_t*)malloc(block_size)) == nullptr) {
fprintf(stderr, "Unable to allocate %lu bytes for the buffer.\n", block_size);
return -1;
}
if (seek > 0) {
if (lseek(output_fd, seek * block_size, SEEK_SET) < 0) {
fprintf(stderr, "Unable to seek %lu bytes.\n", seek * block_size);
return -1;
}
}
while (1) {
nread = read(input_fd, buffer, block_size);
if (nread < 0) {
fprintf(stderr, "Cannot read from the input.\n");
break;
} else if (nread == 0) {
break;
} else {
if ((size_t)nread != block_size) {
partial_blocks_in++;
} else {
total_blocks_in++;
}
if (partial_blocks_in + total_blocks_in <= skip) {
continue;
}
nwritten = write(output_fd, buffer, nread);
if (nwritten < 0) {
fprintf(stderr, "Cannot write to the output.\n");
break;
} else if (nwritten == 0) {
break;
} else {
if ((size_t)nwritten < block_size) {
partial_blocks_out++;
} else {
total_blocks_out++;
}
total_bytes_copied += nwritten;
if (count > 0 && (partial_blocks_out + total_blocks_out) >= count) {
break;
}
}
}
}
if (status == Default) {
fprintf(stderr, "%lu+%lu blocks in\n", total_blocks_in, partial_blocks_in);
fprintf(stderr, "%lu+%lu blocks out\n", total_blocks_out, partial_blocks_out);
fprintf(stderr, "%lu bytes copied.\n", total_bytes_copied);
}
free(buffer);
if (input_fd != 0) {
close(input_fd);
}
if (output_fd != 1) {
close(output_fd);
}
return 0;
}
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