booster: Clean-up handling of log/fstab env variables

Handle two cases when deciding log/fstab file:
1. It turns out that that strdup or strlen doesnt actually
check for NULL before trying to do its thing with the string
so it seg-faults on seeing a NULL char pointer.

2. getenv can return an empty string if the
env var was exported as:
$ export GLUSTEFS_BOOSTER_LOG=

Signed-off-by: Anand V. Avati <avati@dev.gluster.com>

1 files changed, 14 insertions, 5 deletions

diff --git a/booster/src/booster.c b/booster/src/booster.c
index b51cc25cae3..cb35be519d3 100644
--- a/booster/src/booster.c
+++ b/booster/src/booster.c
@@ -376,6 +376,7 @@ mbp_open (int fd, dev_t file_devno)
         FILE *specfp = NULL;
         int32_t file_size = -1;
         int ret = -1;
+        char *logfile = NULL;
         glusterfs_handle_t handle = NULL;
 
         glusterfs_init_params_t ctx = {
@@ -409,8 +410,13 @@ mbp_open (int fd, dev_t file_devno)
                 goto out;
 
         fseek (specfp, 0L, SEEK_SET);
-        ctx.logfile = strdup (getenv (BOOSTER_LOG_ENV_VAR));
-        if (!ctx.logfile)
+        logfile = getenv (BOOSTER_LOG_ENV_VAR);
+        if (logfile) {
+                if (strlen (logfile) > 0)
+                        ctx.logfile = strdup (logfile);
+                else
+                        ctx.logfile = strdup (BOOSTER_DEFAULT_LOG);
+        } else
                 ctx.logfile = strdup (BOOSTER_DEFAULT_LOG);
 
         ctx.specfp = specfp;
@@ -1178,10 +1184,13 @@ booster_init (void)
          * socket calls will fall-back to the real API.
          */
         booster_conf_path = getenv (BOOSTER_CONF_ENV_VAR);
-        if (booster_conf_path == NULL)
+        if (booster_conf_path != NULL) {
+                if (strlen (booster_conf_path) > 0)
+                        ret = booster_configure (booster_conf_path);
+                else
+                        ret = booster_configure (DEFAULT_BOOSTER_CONF);
+        } else
                 ret = booster_configure (DEFAULT_BOOSTER_CONF);
-        else
-                ret = booster_configure (booster_conf_path);
 
         if (ret == 0)
                 gf_log ("booster", GF_LOG_DEBUG, "booster is inited");