67 lines
989 B
C++
67 lines
989 B
C++
#include <fcntl.h>
|
|
#include <stdio.h>
|
|
#include <sys/mman.h>
|
|
#include <sys/stat.h>
|
|
|
|
bool cat_file(int fd)
|
|
{
|
|
struct stat st;
|
|
if (fstat(fd, &st) == -1)
|
|
{
|
|
perror("stat");
|
|
return false;
|
|
}
|
|
|
|
void* addr = mmap(nullptr, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
|
|
if (addr == MAP_FAILED)
|
|
{
|
|
perror("mmap");
|
|
return false;
|
|
}
|
|
|
|
ssize_t nwrite = write(STDOUT_FILENO, addr, st.st_size);
|
|
if (nwrite == -1)
|
|
perror("write");
|
|
|
|
if (static_cast<uint8_t*>(addr)[st.st_size - 1] != '\n')
|
|
if (write(STDOUT_FILENO, "\n", 1) == -1)
|
|
perror("write");
|
|
|
|
if (munmap(addr, st.st_size) == -1)
|
|
{
|
|
perror("munmap");
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
int main(int argc, char** argv)
|
|
{
|
|
int ret = 0;
|
|
|
|
if (argc > 1)
|
|
{
|
|
for (int i = 1; i < argc; i++)
|
|
{
|
|
int fd = open(argv[i], O_RDONLY);
|
|
if (fd == -1)
|
|
{
|
|
perror(argv[i]);
|
|
ret = 1;
|
|
continue;
|
|
}
|
|
if (!cat_file(fd))
|
|
ret = 1;
|
|
close(fd);
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if (!cat_file(STDIN_FILENO))
|
|
ret = 1;
|
|
}
|
|
|
|
return ret;
|
|
}
|