#include <stdlib.h>
#include <dirent.h>
#include <string.h>
-
+#include <fcntl.h>
+#include <sys/poll.h>
enum {
GET_SUBBUF,
static char *trace_name = NULL;
static char *channel_name = NULL;
static int daemon_mode = 0;
-
+static int append_mode = 0;
/* Args :
*
* -t directory Directory name of the trace to write to. Will be created.
* -c directory Root directory of the relayfs trace channels.
* -d Run in background (daemon).
+ * -a Trace append mode.
*/
void show_arguments(void)
{
" It will be created.\n");
printf("-c directory Root directory of the relayfs trace channels.\n");
printf("-d Run in background (daemon).\n");
+ printf("-a Append to an possibly existing trace.\n");
printf("\n");
}
}
}
- while(argn < argc-1) {
+ while(argn < argc) {
switch(argv[argn][0]) {
case '-':
switch(argv[argn][1]) {
case 't':
- trace_name = argv[argn+1];
- argn++;
+ if(argn+1 < argc) {
+ trace_name = argv[argn+1];
+ argn++;
+ }
break;
case 'c':
- channel_name = argv[argn+1];
- argn++;
+ if(argn+1 < argc) {
+ channel_name = argv[argn+1];
+ argn++;
+ }
break;
case 'd':
daemon_mode = 1;
break;
+ case 'a':
+ append_mode = 1;
+ break;
default:
printf("Invalid argument '%s'.\n", argv[argn]);
printf("\n");
printf("Creating trace subdirectory %s\n", subtrace_name);
ret = mkdir(subtrace_name, S_IRWXU|S_IRWXG|S_IRWXO);
if(ret == -1) {
- perror(subtrace_name);
- return -1;
+ if(errno == EEXIST && append_mode) {
+ printf("Appending to directory %s as resquested\n", subtrace_name);
+ } else {
+ perror(subtrace_name);
+ return -1;
+ }
}
strncpy(path_channel, subchannel_name, PATH_MAX-1);
printf("Entering channel subdirectory...\n");
ret = open_channel_trace_pairs(path_channel, path_trace, fd_pairs);
if(ret < 0) continue;
+ } else if(S_ISREG(stat_buf.st_mode)) {
+ printf("Opening file.\n");
+
+ fd_pairs->pair = realloc(fd_pairs->pair,
+ ++fd_pairs->num_pairs * sizeof(struct fd_pair));
+
+ /* Open the channel in read mode */
+ fd_pairs->pair[fd_pairs->num_pairs-1].channel =
+ open(path_channel, O_RDONLY | O_NONBLOCK);
+ if(fd_pairs->pair[fd_pairs->num_pairs-1].channel == -1) {
+ perror(path_channel);
+ }
+ /* Open the trace in write mode, only append if append_mode */
+ ret = stat(path_trace, &stat_buf);
+ if(ret == 0) {
+ if(append_mode) {
+ printf("Appending to file %s as resquested\n", path_trace);
+
+ fd_pairs->pair[fd_pairs->num_pairs-1].trace =
+ open(path_trace, O_WRONLY|O_APPEND,
+ S_IRWXU|S_IRWXG|S_IRWXO);
+
+ if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) {
+ perror(path_trace);
+ }
+ } else {
+ printf("File %s exists, cannot open. Try append mode.\n", path_trace);
+ return -1;
+ }
+ } else {
+ if(errno == ENOENT) {
+ fd_pairs->pair[fd_pairs->num_pairs-1].trace =
+ open(path_trace, O_WRONLY|O_CREAT|O_EXCL,
+ S_IRWXU|S_IRWXG|S_IRWXO);
+ if(fd_pairs->pair[fd_pairs->num_pairs-1].trace == -1) {
+ perror(path_trace);
+ }
+ }
+ }
}
-
}
closedir(channel_dir);
return 0;
}
+/* read_channels
+ *
+ * Read the realyfs channels and write them in the paired tracefiles.
+ *
+ * @fd_pairs : paired channels and trace files.
+ *
+ * returns 0 on success, -1 on error.
+ *
+ * Note that the high priority polled channels are consumed first. We then poll
+ * again to see if these channels are still in priority. Only when no
+ * high priority channel is left, we start reading low priority channels.
+ *
+ * Note that a channel is considered high priority when the buffer is almost
+ * full.
+ */
int read_channels(struct channel_trace_fd *fd_pairs)
{
+ struct pollfd *pollfd;
+ int i;
+ int num_rdy;
+
+ pollfd = malloc(fd_pairs->num_pairs * sizeof(struct pollfd));
+
+ for(i=0;i<fd_pairs->num_pairs;i++) {
+ pollfd[i].fd = fd_pairs->pair[i].channel;
+ pollfd[i].events = POLLIN|POLLPRI;
+ }
+
+ while(1) {
+
+ num_rdy = poll(pollfd, fd_pairs->num_pairs, -1);
+ if(num_rdy == -1) {
+ perror("Poll error");
+ return -1;
+ }
+
+ printf("Data received\n");
+
+ for(i=0;i<fd_pairs->num_pairs;i++) {
+ switch(pollfd[i].revents) {
+ case POLLERR:
+ printf("Error returned in polling fd %d.\n", pollfd[i].fd);
+ break;
+ case POLLHUP:
+ printf("Polling fd %d tells it has hung up.\n", pollfd[i].fd);
+ break;
+ case POLLNVAL:
+ printf("Polling fd %d tells fd is not open.\n", pollfd[i].fd);
+ break;
+ case POLLPRI:
+ /* Take care of high priority channels first. */
+ break;
+ default:
+ }
+
+ for(i=0;i<fd_pairs->num_pairs;i++) {
+ switch(pollfd[i].revents) {
+ case POLLIN:
+ /* Take care of low priority channels. */
+ break;
+ default:
+ }
+
+ }
+
+ free(pollfd);
+
return 0;
}
void close_channel_trace_pairs(struct channel_trace_fd *fd_pairs)
{
+ int i;
+ int ret;
+ for(i=0;i<fd_pairs->num_pairs;i++) {
+ ret = close(fd_pairs->pair[i].channel);
+ if(ret == -1) perror("Close error on channel");
+ ret = close(fd_pairs->pair[i].trace);
+ if(ret == -1) perror("Close error on trace");
+ }
+ free(fd_pairs->pair);
}
int main(int argc, char ** argv)
}
if(ret = open_channel_trace_pairs(channel_name, trace_name, &fd_pairs))
- goto end_main;
+ goto close_channel;
ret = read_channels(&fd_pairs);
+close_channel:
close_channel_trace_pairs(&fd_pairs);
-end_main:
-
return ret;
}
projects / ltt-control.git / commitdiff
