static inline FILE* get_fifo_stream(FILE *old_stream)
{
int fd, n;
struct stat fst;
if (mi_reload_fifo == 0) {
fd = fileno(old_stream);
if (!mi_fifo_check(fd, mi_fifo_name))
return old_stream;
LM_INFO("invalid FIFO file: creating a new one (%s)\n", mi_fifo_name);
} else {
LM_INFO("Forcefully replacing FIFO file (%s)\n", mi_fifo_name);
}
/* here we are either forced to reload or the check did not pass */
n = stat(mi_fifo_name, &fst);
if (n == 0) {
if (unlink(mi_fifo_name) < 0) {
LM_ERR("cannot delete fifo file %s\n", mi_fifo_name);
return NULL;
}
LM_INFO("deleted FIFO file (%s)\n", mi_fifo_name);
} else if (n < 0 && errno != ENOENT) {
LM_ERR("stat failed: %s\n", strerror(errno));
return NULL;
}
mi_reload_fifo = 0;
return mi_create_fifo();
}
int mi_open_reply_pipe( char *pipe_name )
{
int fifofd;
int retries=FIFO_REPLY_RETRIES;
if (!pipe_name || *pipe_name==0) {
LM_DBG("no file to write to about missing cmd\n");
return -1;
}
tryagain:
/* open non-blocking to make sure that a broken client will not
* block the FIFO server forever */
fifofd=open( pipe_name, O_WRONLY | O_NONBLOCK );
if (fifofd==-1) {
/* retry several times if client is not yet ready for getting
feedback via a reply pipe
*/
if (errno==ENXIO) {
/* give up on the client - we can't afford server blocking */
if (retries==0) {
LM_ERR("no client at %s\n",pipe_name );
return -1;
}
/* don't be noisy on the very first try */
if (retries!=FIFO_REPLY_RETRIES)
LM_DBG("retry countdown: %d\n", retries );
sleep_us( FIFO_REPLY_WAIT );
retries--;
goto tryagain;
}
/* some other opening error */
LM_ERR("open error (%s): %s\n", pipe_name, strerror(errno));
return -1;
}
/* security checks: is this really a fifo?, is
* it hardlinked? is it a soft link? */
if (mi_fifo_check(fifofd, pipe_name)<0) goto error;
return fifofd;
error:
close(fifofd);
return -1;
}
static FILE *mi_open_reply_pipe( char *pipe_name )
{
int fifofd;
FILE *file_handle;
int flags;
int retries=FIFO_REPLY_RETRIES;
if (!pipe_name || *pipe_name==0) {
LM_DBG("no file to write to about missing cmd\n");
return 0;
}
tryagain:
/* open non-blocking to make sure that a broken client will not
* block the FIFO server forever */
fifofd=open( pipe_name, O_WRONLY | O_NONBLOCK );
if (fifofd==-1) {
/* retry several times if client is not yet ready for getting
feedback via a reply pipe
*/
if (errno==ENXIO) {
/* give up on the client - we can't afford server blocking */
if (retries==0) {
LM_ERR("no client at %s\n",pipe_name );
return 0;
}
/* don't be noisy on the very first try */
if (retries!=FIFO_REPLY_RETRIES)
LM_DBG("retry countdown: %d\n", retries );
sleep_us( FIFO_REPLY_WAIT );
retries--;
goto tryagain;
}
/* some other opening error */
LM_ERR("open error (%s): %s\n", pipe_name, strerror(errno));
return 0;
}
/* security checks: is this really a fifo?, is
* it hardlinked? is it a soft link? */
if (mi_fifo_check(fifofd, pipe_name)<0) goto error;
/* we want server blocking for big writes */
if ( (flags=fcntl(fifofd, F_GETFL, 0))<0) {
LM_ERR("pipe (%s): getfl failed: %s\n", pipe_name, strerror(errno));
goto error;
}
flags&=~O_NONBLOCK;
if (fcntl(fifofd, F_SETFL, flags)<0) {
LM_ERR("pipe (%s): setfl cntl failed: %s\n", pipe_name, strerror(errno));
goto error;
}
/* create an I/O stream */
file_handle=fdopen( fifofd, "w");
if (file_handle==NULL) {
LM_ERR("open error (%s): %s\n",
pipe_name, strerror(errno));
goto error;
}
return file_handle;
error:
close(fifofd);
return 0;
}
