Move stream file rotation functions to utils

[lttng-tools.git] / src / common / utils.c

diff --git a/src/common/utils.c b/src/common/utils.c
index a18e906d7f6b303d834482b2b00ce7f93a1fcdf5..9f3a8f942b1176867fc7e0d55253cbae321f6130 100644 (file)
--- a/src/common/utils.c
+++ b/src/common/utils.c
@@ -25,8 +25,10 @@
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <unistd.h>
+#include <inttypes.h>
 
 #include <common/common.h>
+#include <common/runas.h>
 
 #include "utils.h"
 
@@ -301,3 +303,85 @@ int utils_mkdir_recursive(const char *path, mode_t mode)
 error:
        return ret;
 }
+
+/*
+ * Create the stream tracefile on disk.
+ *
+ * Return 0 on success or else a negative value.
+ */
+int utils_create_stream_file(char *path_name, char *file_name, uint64_t size,
+               uint64_t count, int uid, int gid)
+{
+       int ret, out_fd;
+       char full_path[PATH_MAX], *path_name_id = NULL, *path;
+
+       assert(path_name);
+       assert(file_name);
+
+       ret = snprintf(full_path, sizeof(full_path), "%s/%s",
+                       path_name, file_name);
+       if (ret < 0) {
+               PERROR("snprintf create output file");
+               goto error;
+       }
+
+       /*
+        * If we split the trace in multiple files, we have to add the count at the
+        * end of the tracefile name
+        */
+       if (size > 0) {
+               ret = asprintf(&path_name_id, "%s_%" PRIu64, full_path, count);
+               if (ret < 0) {
+                       PERROR("Allocating path name ID");
+                       goto error;
+               }
+               path = path_name_id;
+       } else {
+               path = full_path;
+       }
+
+       out_fd = run_as_open(path, O_WRONLY | O_CREAT | O_TRUNC,
+                       S_IRWXU | S_IRWXG | S_IRWXO, uid, gid);
+       if (out_fd < 0) {
+               PERROR("open stream path %s", path);
+               goto error_open;
+       }
+       ret = out_fd;
+
+error_open:
+       free(path_name_id);
+error:
+       return ret;
+}
+
+/*
+ * Change the output tracefile according to the given size and count The
+ * new_count pointer is set during this operation.
+ *
+ * From the consumer, the stream lock MUST be held before calling this function
+ * because we are modifying the stream status.
+ *
+ * Return 0 on success or else a negative value.
+ */
+int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size,
+               uint64_t count, int uid, int gid, int out_fd, uint64_t *new_count)
+{
+       int ret;
+
+       ret = close(out_fd);
+       if (ret < 0) {
+               PERROR("Closing tracefile");
+               goto error;
+       }
+
+       if (count > 0) {
+               *new_count = (*new_count + 1) % count;
+       } else {
+               (*new_count)++;
+       }
+
+       return utils_create_stream_file(path_name, file_name, size, *new_count,
+                       uid, gid);
+error:
+       return ret;
+}