105 lines
2.2 KiB
C
105 lines
2.2 KiB
C
#include <stdio.h> // printf
|
|
#include <fcntl.h>
|
|
#include <string.h> // memchr
|
|
#include <unistd.h> // read write
|
|
#include <stdint.h> // uint32_t
|
|
#include <stdlib.h> // exit
|
|
#include <poll.h> // poll
|
|
|
|
// OUTPUT: line-by-line strings
|
|
|
|
#define line_size_exceeded "line exeeded max buffer size\n"
|
|
#define MAXBUFFER 64000
|
|
|
|
char buf[MAXBUFFER];
|
|
|
|
void err(int error, const char *str) {
|
|
fprintf (stderr, "%s\n", str);
|
|
exit(error);
|
|
}
|
|
|
|
int main(int argc, const char **argv)
|
|
{
|
|
if (argc > 1) {
|
|
printf ("usage: %s\n", argv[0]);
|
|
return 0;
|
|
}
|
|
|
|
// fcntl(0, F_SETFL, O_SYNC);
|
|
|
|
uint32_t tot_read = 0;
|
|
uint32_t n_read = 0;
|
|
struct pollfd pfd[1];
|
|
int nready;
|
|
|
|
pfd[0].fd = 0;
|
|
|
|
while (1) {
|
|
pfd[0].events = POLLIN;
|
|
nready = poll(pfd, 1, 60 * 1000);
|
|
|
|
if (nready == -1)
|
|
err (1, "poll");
|
|
|
|
if (nready == 0) {
|
|
fprintf (stderr, "time out\n");
|
|
}
|
|
|
|
if ((pfd[0].revents & (POLLERR|POLLNVAL))) {
|
|
fprintf (stderr, "bad fd %d", pfd[0].fd);
|
|
err (1, "bad fd");
|
|
}
|
|
|
|
if ((pfd[0].revents & (POLLIN|POLLHUP))) {
|
|
n_read = read(0, buf, sizeof(buf));
|
|
if (n_read > 0) {
|
|
// fprintf (stderr, "read %u characters\n", n_read);
|
|
|
|
tot_read += n_read;
|
|
// fprintf(stderr, "total read %u\n", tot_read);
|
|
// fprintf(stderr, "could still read %u\n", MAXBUFFER - tot_read);
|
|
if (tot_read == MAXBUFFER) {
|
|
// print anyway
|
|
write (1, buf, tot_read);
|
|
write (2, line_size_exceeded, strlen(line_size_exceeded));
|
|
printf(buf);
|
|
n_read = 0;
|
|
tot_read = 0;
|
|
continue;
|
|
}
|
|
|
|
// print line by line (if any)
|
|
char * p = NULL;
|
|
while ((p = memchr(buf, '\n', tot_read)) != NULL) {
|
|
uint32_t remaining = tot_read - (p - buf) - 1;
|
|
write (1, buf, tot_read - remaining);
|
|
// fprintf (stderr, "found retline, %u remaining chars\n", remaining);
|
|
|
|
for (uint32_t i = 0; i < remaining ; i++) {
|
|
buf[i] = buf[i + tot_read - remaining];
|
|
}
|
|
tot_read = remaining;
|
|
n_read = 0;
|
|
}
|
|
|
|
}
|
|
else if (n_read == 0) {
|
|
// fprintf (stderr, "EOF\n");
|
|
break;
|
|
}
|
|
else {
|
|
err (1, "read");
|
|
}
|
|
}
|
|
}
|
|
|
|
if (tot_read > 0) {
|
|
// fprintf(stderr, "print the %u characters remaining in the buffer\n", tot_read);
|
|
write (1, buf, tot_read);
|
|
}
|
|
|
|
// fprintf (stderr, "end of the loop\n");
|
|
|
|
return 0;
|
|
}
|