Health check: implement health check query in sessiond and consumerd

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

diff --git a/src/common/utils.c b/src/common/utils.c
index cfb6555a1d65fc061eb20c2c69326a91175f97ec..da4c036b9630a3ecddebd9aa74d419609705379d 100644 (file)
--- a/src/common/utils.c
+++ b/src/common/utils.c
@@ -27,6 +27,7 @@
 #include <unistd.h>
 #include <inttypes.h>
 #include <regex.h>
+#include <grp.h>
 
 #include <common/common.h>
 #include <common/runas.h>
@@ -142,6 +143,48 @@ error:
        return ret;
 }
 
+/*
+ * Create pipe and set fd flags to FD_CLOEXEC and O_NONBLOCK.
+ *
+ * Make sure the pipe opened by this function are closed at some point. Use
+ * utils_close_pipe(). Using pipe() and fcntl rather than pipe2() to
+ * support OSes other than Linux 2.6.23+.
+ */
+LTTNG_HIDDEN
+int utils_create_pipe_cloexec_nonblock(int *dst)
+{
+       int ret, i;
+
+       if (dst == NULL) {
+               return -1;
+       }
+
+       ret = utils_create_pipe(dst);
+       if (ret < 0) {
+               goto error;
+       }
+
+       for (i = 0; i < 2; i++) {
+               ret = fcntl(dst[i], F_SETFD, FD_CLOEXEC);
+               if (ret < 0) {
+                       PERROR("fcntl pipe cloexec");
+                       goto error;
+               }
+               /*
+                * Note: we override any flag that could have been
+                * previously set on the fd.
+                */
+               ret = fcntl(dst[i], F_SETFL, O_NONBLOCK);
+               if (ret < 0) {
+                       PERROR("fcntl pipe nonblock");
+                       goto error;
+               }
+       }
+
+error:
+       return ret;
+}
+
 /*
  * Close both read and write side of the pipe.
  */
@@ -309,10 +352,11 @@ error:
  */
 LTTNG_HIDDEN
 int utils_create_stream_file(const char *path_name, char *file_name, uint64_t size,
-               uint64_t count, int uid, int gid)
+               uint64_t count, int uid, int gid, char *suffix)
 {
        int ret, out_fd, flags, mode;
-       char full_path[PATH_MAX], *path_name_id = NULL, *path;
+       char full_path[PATH_MAX], *path_name_suffix = NULL, *path;
+       char *extra = NULL;
 
        assert(path_name);
        assert(file_name);
@@ -324,17 +368,30 @@ int utils_create_stream_file(const char *path_name, char *file_name, uint64_t si
                goto error;
        }
 
+       /* Setup extra string if suffix or/and a count is needed. */
+       if (size > 0 && suffix) {
+               ret = asprintf(&extra, "_%" PRIu64 "%s", count, suffix);
+       } else if (size > 0) {
+               ret = asprintf(&extra, "_%" PRIu64, count);
+       } else if (suffix) {
+               ret = asprintf(&extra, "%s", suffix);
+       }
+       if (ret < 0) {
+               PERROR("Allocating extra string to name");
+               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 (extra) {
+               ret = asprintf(&path_name_suffix, "%s%s", full_path, extra);
                if (ret < 0) {
-                       PERROR("Allocating path name ID");
-                       goto error;
+                       PERROR("Allocating path name with extra string");
+                       goto error_free_suffix;
                }
-               path = path_name_id;
+               path = path_name_suffix;
        } else {
                path = full_path;
        }
@@ -355,7 +412,9 @@ int utils_create_stream_file(const char *path_name, char *file_name, uint64_t si
        ret = out_fd;
 
 error_open:
-       free(path_name_id);
+       free(path_name_suffix);
+error_free_suffix:
+       free(extra);
 error:
        return ret;
 }
@@ -371,10 +430,14 @@ error:
  */
 LTTNG_HIDDEN
 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)
+               uint64_t count, int uid, int gid, int out_fd, uint64_t *new_count,
+               int *stream_fd)
 {
        int ret;
 
+       assert(new_count);
+       assert(stream_fd);
+
        ret = close(out_fd);
        if (ret < 0) {
                PERROR("Closing tracefile");
@@ -387,8 +450,16 @@ int utils_rotate_stream_file(char *path_name, char *file_name, uint64_t size,
                (*new_count)++;
        }
 
-       return utils_create_stream_file(path_name, file_name, size, *new_count,
-                       uid, gid);
+       ret = utils_create_stream_file(path_name, file_name, size, *new_count,
+                       uid, gid, 0);
+       if (ret < 0) {
+               goto error;
+       }
+       *stream_fd = ret;
+
+       /* Success. */
+       ret = 0;
+
 error:
        return ret;
 }
@@ -624,3 +695,24 @@ size_t utils_get_current_time_str(const char *format, char *dst, size_t len)
 
        return ret;
 }
+
+/*
+ * Return the group ID matching name, else 0 if it cannot be found.
+ */
+LTTNG_HIDDEN
+gid_t utils_get_group_id(const char *name)
+{
+       struct group *grp;
+
+       grp = getgrnam(name);
+       if (!grp) {
+               static volatile int warn_once;
+
+               if (!warn_once) {
+                       WARN("No tracing group detected");
+                       warn_once = 1;
+               }
+               return 0;
+       }
+       return grp->gr_gid;
+}