fix broken external ioengine option

[fio.git] / options.c

diff --git a/options.c b/options.c
index 443791abc6b1dc46400ec057abc0c03e83ea8023..54fa4eef7ac5965792ff0fae3aeeaad85470a7c5 100644 (file)
--- a/options.c
+++ b/options.c
@@ -1462,6 +1462,39 @@ static int str_write_hist_log_cb(void *data, const char *str)
        return 0;
 }
 
+/*
+ * str is supposed to be a substring of the strdup'd original string,
+ * and is valid only if it's a regular file path.
+ * This function keeps the pointer to the path as needed later.
+ *
+ * "external:/path/to/so\0" <- original pointer updated with strdup'd
+ * "external\0"             <- above pointer after parsed, i.e. ->ioengine
+ *          "/path/to/so\0" <- str argument, i.e. ->ioengine_so_path
+ */
+static int str_ioengine_external_cb(void *data, const char *str)
+{
+       struct thread_data *td = cb_data_to_td(data);
+       struct stat sb;
+       char *p;
+
+       if (!str) {
+               log_err("fio: null external ioengine path\n");
+               return 1;
+       }
+
+       p = (char *)str; /* str is mutable */
+       strip_blank_front(&p);
+       strip_blank_end(p);
+
+       if (stat(p, &sb) || !S_ISREG(sb.st_mode)) {
+               log_err("fio: invalid external ioengine path \"%s\"\n", p);
+               return 1;
+       }
+
+       td->o.ioengine_so_path = p;
+       return 0;
+}
+
 static int rw_verify(struct fio_option *o, void *data)
 {
        struct thread_data *td = cb_data_to_td(data);
@@ -1812,6 +1845,7 @@ struct fio_option fio_options[FIO_MAX_OPTS] = {
 #endif
                          { .ival = "external",
                            .help = "Load external engine (append name)",
+                           .cb = str_ioengine_external_cb,
                          },
                },
        },