+/* liblttdutils
+ *
+ * Linux Trace Toolkit utility library
+ *
+ * This is a simple daemon implementation that reads a few relay+debugfs
+ * channels and save them in a trace.
+ *
+ * CPU hot-plugging is supported using inotify.
+ *
+ * Copyright 2005 -
+ * Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
+ * Copyright 2010 -
+ * Michael Sills-Lavoie <michael.sills-lavoie@polymtl.ca>
+ * Oumarou Dicko <oumarou.dicko@polymtl.ca>
+ */
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#define _REENTRANT
+#define _GNU_SOURCE
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <dirent.h>
+#include <pthread.h>
+#include <sys/stat.h>
+
+#include "liblttdutils.h"
+
+struct liblttdutils_channel_data {
+ int trace;
+};
+
+struct liblttdutils_data {
+ char path_trace[PATH_MAX];
+ char *end_path_trace;
+ int path_trace_len;
+ int append_mode;
+ int verbose_mode;
+};
+
+static __thread int thread_pipe[2];
+
+#define printf_verbose(fmt, args...) \
+ do { \
+ if (callbacks_data->verbose_mode) \
+ printf(fmt, ##args); \
+ } while (0)
+
+int liblttdutils_local_on_open_channel(struct liblttd_callbacks *data, struct fd_pair *pair, char *relative_channel_path)
+{
+ int open_ret = 0;
+ int ret;
+ struct stat stat_buf;
+ struct liblttdutils_channel_data *channel_data;
+
+ pair->user_data = malloc(sizeof(struct liblttdutils_channel_data));
+ channel_data = pair->user_data;
+
+ struct liblttdutils_data* callbacks_data = data->user_data;
+
+ strncpy(callbacks_data->end_path_trace, relative_channel_path, PATH_MAX - callbacks_data->path_trace_len);
+ printf_verbose("Creating trace file %s\n", callbacks_data->path_trace);
+
+ ret = stat(callbacks_data->path_trace, &stat_buf);
+ if(ret == 0) {
+ if(callbacks_data->append_mode) {
+ printf_verbose("Appending to file %s as requested\n",
+ callbacks_data->path_trace);
+
+ channel_data->trace = open(callbacks_data->path_trace, O_WRONLY, S_IRWXU|S_IRWXG|S_IRWXO);
+ if(channel_data->trace == -1) {
+ perror(callbacks_data->path_trace);
+ open_ret = -1;
+ goto end;
+ }
+ ret = lseek(channel_data->trace, 0, SEEK_END);
+ if (ret < 0) {
+ perror(callbacks_data->path_trace);
+ open_ret = -1;
+ close(channel_data->trace);
+ goto end;
+ }
+ } else {
+ printf("File %s exists, cannot open. Try append mode.\n", callbacks_data->path_trace);
+ open_ret = -1;
+ goto end;
+ }
+ } else {
+ if(errno == ENOENT) {
+ channel_data->trace =
+ open(callbacks_data->path_trace, O_WRONLY|O_CREAT|O_EXCL, S_IRWXU|S_IRWXG|S_IRWXO);
+ if(channel_data->trace == -1) {
+ perror(callbacks_data->path_trace);
+ open_ret = -1;
+ goto end;
+ }
+ }
+ }
+
+end:
+ return open_ret;
+
+}
+
+int liblttdutils_local_on_close_channel(struct liblttd_callbacks *data, struct fd_pair *pair)
+{
+ int ret;
+ ret = close(((struct liblttdutils_channel_data *)(pair->user_data))->trace);
+ free(pair->user_data);
+ return ret;
+}
+
+int liblttdutils_local_on_new_channels_folder(struct liblttd_callbacks *data, char *relative_folder_path)
+{
+ int ret;
+ int open_ret = 0;
+ struct liblttdutils_data* callbacks_data = data->user_data;
+
+ strncpy(callbacks_data->end_path_trace, relative_folder_path, PATH_MAX - callbacks_data->path_trace_len);
+ printf_verbose("Creating trace subdirectory %s\n", callbacks_data->path_trace);
+
+ ret = mkdir(callbacks_data->path_trace, S_IRWXU|S_IRWXG|S_IRWXO);
+ if(ret == -1) {
+ if(errno != EEXIST) {
+ perror(callbacks_data->path_trace);
+ open_ret = -1;
+ goto end;
+ }
+ }
+
+end:
+ return open_ret;
+}
+
+int liblttdutils_local_on_read_subbuffer(struct liblttd_callbacks *data, struct fd_pair *pair, unsigned int len)
+{
+ long ret;
+ off_t offset = 0;
+
+ struct liblttdutils_data* callbacks_data = data->user_data;
+
+ while (len > 0) {
+ printf_verbose("splice chan to pipe offset %lu\n",
+ (unsigned long)offset);
+ ret = splice(pair->channel, &offset, thread_pipe[1], NULL,
+ len, SPLICE_F_MOVE | SPLICE_F_MORE);
+ printf_verbose("splice chan to pipe ret %ld\n", ret);
+ if (ret < 0) {
+ perror("Error in relay splice");
+ goto write_error;
+ }
+ ret = splice(thread_pipe[0], NULL,
+ ((struct liblttdutils_channel_data *)(pair->user_data))->trace,
+ NULL, ret, SPLICE_F_MOVE | SPLICE_F_MORE);
+ printf_verbose("splice pipe to file %ld\n", ret);
+ if (ret < 0) {
+ perror("Error in file splice");
+ goto write_error;
+ }
+ len -= ret;
+ }
+
+write_error:
+ return ret;
+}
+
+int liblttdutils_local_on_new_thread(struct liblttd_callbacks *data, unsigned long thread_num)
+{
+ int ret;
+ ret = pipe(thread_pipe);
+ if (ret < 0) {
+ perror("Error creating pipe");
+ return ret;
+ }
+ return 0;
+}
+
+int liblttdutils_local_on_close_thread(struct liblttd_callbacks *data, unsigned long thread_num)
+{
+ close(thread_pipe[0]); /* close read end */
+ close(thread_pipe[1]); /* close write end */
+ return 0;
+}
+
+int liblttdutils_local_on_trace_end(struct liblttd_instance *instance)
+{
+ struct liblttd_callbacks *callbacks = instance->callbacks;
+ struct liblttdutils_data *data = callbacks->user_data;
+
+ free(data);
+ free(callbacks);
+}
+
+struct liblttd_callbacks* liblttdutils_local_new_callbacks(char* trace_name,
+ int append_mode, int verbose_mode)
+{
+ struct liblttdutils_data *data;
+ struct liblttd_callbacks *callbacks;
+
+ if(!trace_name) return NULL;
+
+ data = malloc(sizeof(struct liblttdutils_data));
+
+ strncpy(data->path_trace, trace_name, PATH_MAX-1);
+ data->path_trace_len = strlen(data->path_trace);
+ data->end_path_trace = data->path_trace + data->path_trace_len;
+ data->append_mode = append_mode;
+ data->verbose_mode = verbose_mode;
+
+ callbacks = malloc(sizeof(struct liblttd_callbacks));
+
+ callbacks->on_open_channel = liblttdutils_local_on_open_channel;
+ callbacks->on_close_channel = liblttdutils_local_on_close_channel;
+ callbacks->on_new_channels_folder = liblttdutils_local_on_new_channels_folder;
+ callbacks->on_read_subbuffer = liblttdutils_local_on_read_subbuffer;
+ callbacks->on_trace_end = liblttdutils_local_on_trace_end;
+ callbacks->on_new_thread = liblttdutils_local_on_new_thread;
+ callbacks->on_close_thread = liblttdutils_local_on_close_thread;
+ callbacks->user_data = data;
+
+ return callbacks;
+}
+