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#include <AK/String.h>
#include <AK/FileSystemPath.h>
#include <AK/StringBuilder.h>
#include <LibCore/CArgsParser.h>
#include <LibCore/CDirIterator.h>
#include <assert.h>
#include <fcntl.h>
#include <stdio.h>
#include <sys/stat.h>
#include <unistd.h>
bool copy_file_or_directory(String, String, bool);
bool copy_file(String, String, struct stat, int);
bool copy_directory(String, String);
int main(int argc, char** argv)
{
CArgsParser args_parser("cp");
args_parser.add_arg("r", "copy directories recursively");
args_parser.add_required_single_value("source");
args_parser.add_required_single_value("destination");
CArgsParserResult args = args_parser.parse(argc, argv);
Vector<String> values = args.get_single_values();
if (values.size() == 0) {
args_parser.print_usage();
return 0;
}
bool recursion_allowed = args.is_present("r");
String src_path = values[0];
String dst_path = values[1];
return copy_file_or_directory(src_path, dst_path, recursion_allowed) ? 0 : 1;
}
/**
* Copy a file or directory to a new location. Returns true if successful, false
* otherwise. If there is an error, its description is output to stderr.
*
* Directories should only be copied if recursion_allowed is set.
*/
bool copy_file_or_directory(String src_path, String dst_path, bool recursion_allowed)
{
int src_fd = open(src_path.characters(), O_RDONLY);
if (src_fd < 0) {
perror("open src");
return false;
}
struct stat src_stat;
int rc = fstat(src_fd, &src_stat);
if (rc < 0) {
perror("stat src");
return false;
}
if (S_ISDIR(src_stat.st_mode)) {
if (!recursion_allowed) {
fprintf(stderr, "cp: -r not specified; omitting directory '%s'\n", src_path.characters());
return false;
}
return copy_directory(src_path, dst_path);
}
return copy_file(src_path, dst_path, src_stat, src_fd);
}
/**
* Copy a source file to a destination file. Returns true if successful, false
* otherwise. If there is an error, its description is output to stderr.
*
* To avoid repeated work, the source file's stat and file descriptor are required.
*/
bool copy_file(String src_path, String dst_path, struct stat src_stat, int src_fd)
{
int dst_fd = creat(dst_path.characters(), 0666);
if (dst_fd < 0) {
if (errno != EISDIR) {
perror("open dst");
return false;
}
StringBuilder builder;
builder.append(dst_path);
builder.append('/');
builder.append(FileSystemPath(src_path).basename());
dst_path = builder.to_string();
dst_fd = creat(dst_path.characters(), 0666);
if (dst_fd < 0) {
perror("open dst");
return false;
}
}
if (src_stat.st_size > 0) {
if (ftruncate(dst_fd, src_stat.st_size) < 0) {
perror("cp: ftruncate");
return false;
}
}
for (;;) {
char buffer[32768];
ssize_t nread = read(src_fd, buffer, sizeof(buffer));
if (nread < 0) {
perror("read src");
return false;
}
if (nread == 0)
break;
ssize_t remaining_to_write = nread;
char* bufptr = buffer;
while (remaining_to_write) {
ssize_t nwritten = write(dst_fd, bufptr, remaining_to_write);
if (nwritten < 0) {
perror("write dst");
return false;
}
assert(nwritten > 0);
remaining_to_write -= nwritten;
bufptr += nwritten;
}
}
auto my_umask = umask(0);
umask(my_umask);
int rc = fchmod(dst_fd, src_stat.st_mode & ~my_umask);
if (rc < 0) {
perror("fchmod dst");
return false;
}
close(src_fd);
close(dst_fd);
return true;
}
/**
* Copy the contents of a source directory into a destination directory.
*/
bool copy_directory(String src_path, String dst_path)
{
int rc = mkdir(dst_path.characters(), 0755);
if (rc < 0) {
perror("cp: mkdir");
return false;
}
CDirIterator di(src_path, CDirIterator::SkipDots);
if (di.has_error()) {
fprintf(stderr, "cp: CDirIterator: %s\n", di.error_string());
return false;
}
while (di.has_next()) {
String filename = di.next_path();
bool is_copied = copy_file_or_directory(
String::format("%s/%s", src_path.characters(), filename.characters()),
String::format("%s/%s", dst_path.characters(), filename.characters()),
true);
if (!is_copied) {
return false;
}
}
return true;
}
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