Relayd add_stream command handle tracefile rotation

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

diff --git a/src/common/utils.c b/src/common/utils.c
index d8cb4a60f1574a936fab23bcf3a9535b2875a136..b16cdc97c2738ad70c23624fc91295c3317b1a66 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"
 
@@ -36,7 +38,7 @@
  * /tmp/test1 does, the real path is returned. In normal time, realpath(3)
  * fails if the end point directory does not exist.
  */
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
 char *utils_expand_path(const char *path)
 {
        const char *end_path = path;
@@ -89,7 +91,7 @@ error:
 /*
  * Create a pipe in dst.
  */
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
 int utils_create_pipe(int *dst)
 {
        int ret;
@@ -112,7 +114,7 @@ int utils_create_pipe(int *dst)
  * Make sure the pipe opened by this function are closed at some point. Use
  * utils_close_pipe().
  */
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
 int utils_create_pipe_cloexec(int *dst)
 {
        int ret, i;
@@ -141,7 +143,7 @@ error:
 /*
  * Close both read and write side of the pipe.
  */
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
 void utils_close_pipe(int *src)
 {
        int i, ret;
@@ -166,7 +168,7 @@ void utils_close_pipe(int *src)
 /*
  * Create a new string using two strings range.
  */
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
 char *utils_strdupdelim(const char *begin, const char *end)
 {
        char *str;
@@ -187,7 +189,7 @@ error:
 /*
  * Set CLOEXEC flag to the give file descriptor.
  */
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
 int utils_set_fd_cloexec(int fd)
 {
        int ret;
@@ -210,7 +212,7 @@ end:
 /*
  * Create pid file to the given path and filename.
  */
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
 int utils_create_pid_file(pid_t pid, const char *filepath)
 {
        int ret;
@@ -241,7 +243,7 @@ error:
  *
  * On success, return 0 else a negative error code.
  */
-__attribute__((visibility("hidden")))
+LTTNG_HIDDEN
 int utils_mkdir_recursive(const char *path, mode_t mode)
 {
        char *p, tmp[PATH_MAX];
@@ -301,3 +303,86 @@ 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;
+       }
+
+       /* Open with 660 mode */
+       out_fd = run_as_open(path, O_WRONLY | O_CREAT | O_TRUNC,
+                       S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP, 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;
+}