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#include "util/non_block_input.h"
#include <unistd.h>
#include <sys/select.h>
#include "pipe.h"
using namespace std;
namespace ov4
{
/*
* read from both stdin, and self pipe
* returns immediately as soon as stdin or pipe is "readable"
* returns read()'s ret value
* and set src to the the read source (stdin or pipe)
*/
int non_block_read_char(char *c, int *src)
{
// get fd check range
int max_fd;
if (STDIN_FILENO > self_pipe_fd[0]) max_fd = STDIN_FILENO;
else max_fd = self_pipe_fd[0];
// monitor STDIN, and self pipe
fd_set rset;
FD_ZERO(&rset);
FD_SET(STDIN_FILENO, &rset);
FD_SET(self_pipe_fd[0], &rset);
select(max_fd+1, &rset, nullptr, nullptr, nullptr);
int ret = -1;
if (FD_ISSET(self_pipe_fd[0], &rset))
{
ret = read(self_pipe_fd[0], c, 1);
if (src != nullptr) *src = self_pipe_fd[0];
}
else if (FD_ISSET(STDIN_FILENO, &rset))
{
ret = read(STDIN_FILENO, c, 1);
if (src != nullptr) *src = self_pipe_fd[0];
}
return ret;
}
}
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