Remove redundant NULL checks

free(NULL) is a valid NOP. Most of the hiredis free functions behave the
same way. redisReaderFree is updated to also be NULL-safe.

There is one redundant NULL check at sds.c:1036, but it's left as is
since sds is imported from upstream.

Signed-off-by: Justin Brewer <jzb0012@auburn.edu>

3 files changed, 18 insertions, 34 deletions

diff --git a/hiredis.c b/hiredis.c
index 8eabac0..98f43c9 100644
--- a/hiredis.c
+++ b/hiredis.c
@@ -84,16 +84,14 @@ void freeReplyObject(void *reply) {
     case REDIS_REPLY_ARRAY:
         if (r->element != NULL) {
             for (j = 0; j < r->elements; j++)
-                if (r->element[j] != NULL)
-                    freeReplyObject(r->element[j]);
+                freeReplyObject(r->element[j]);
             free(r->element);
         }
         break;
     case REDIS_REPLY_ERROR:
     case REDIS_REPLY_STATUS:
     case REDIS_REPLY_STRING:
-        if (r->str != NULL)
-            free(r->str);
+        free(r->str);
         break;
     }
     free(r);
@@ -432,11 +430,7 @@ cleanup:
     }
 
     sdsfree(curarg);
-
-    /* No need to check cmd since it is the last statement that can fail,
-     * but do it anyway to be as defensive as possible. */
-    if (cmd != NULL)
-        free(cmd);
+    free(cmd);
 
     return error_type;
 }
@@ -612,18 +606,12 @@ void redisFree(redisContext *c) {
         return;
     if (c->fd > 0)
         close(c->fd);
-    if (c->obuf != NULL)
-        sdsfree(c->obuf);
-    if (c->reader != NULL)
-        redisReaderFree(c->reader);
-    if (c->tcp.host)
-        free(c->tcp.host);
-    if (c->tcp.source_addr)
-        free(c->tcp.source_addr);
-    if (c->unix_sock.path)
-        free(c->unix_sock.path);
-    if (c->timeout)
-        free(c->timeout);
+    sdsfree(c->obuf);
+    redisReaderFree(c->reader);
+    free(c->tcp.host);
+    free(c->tcp.source_addr);
+    free(c->unix_sock.path);
+    free(c->timeout);
     free(c);
 }
 
diff --git a/net.c b/net.c
index 7ce9ef4..5d50f7c 100644
--- a/net.c
+++ b/net.c
@@ -285,8 +285,7 @@ static int _redisContextConnectTcp(redisContext *c, const char *addr, int port,
      * This is a bit ugly, but atleast it works and doesn't leak memory.
      **/
     if (c->tcp.host != addr) {
-        if (c->tcp.host)
-            free(c->tcp.host);
+        free(c->tcp.host);
 
         c->tcp.host = strdup(addr);
     }
@@ -299,8 +298,7 @@ static int _redisContextConnectTcp(redisContext *c, const char *addr, int port,
             memcpy(c->timeout, timeout, sizeof(struct timeval));
         }
     } else {
-        if (c->timeout)
-            free(c->timeout);
+        free(c->timeout);
         c->timeout = NULL;
     }
 
@@ -452,8 +450,7 @@ int redisContextConnectUnix(redisContext *c, const char *path, const struct time
             memcpy(c->timeout, timeout, sizeof(struct timeval));
         }
     } else {
-        if (c->timeout)
-            free(c->timeout);
+        free(c->timeout);
         c->timeout = NULL;
     }
 
diff --git a/read.c b/read.c
index 4baa74e..2bad85e 100644
--- a/read.c
+++ b/read.c
@@ -52,11 +52,9 @@ static void __redisReaderSetError(redisReader *r, int type, const char *str) {
     }
 
     /* Clear input buffer on errors. */
-    if (r->buf != NULL) {
-        sdsfree(r->buf);
-        r->buf = NULL;
-        r->pos = r->len = 0;
-    }
+    sdsfree(r->buf);
+    r->buf = NULL;
+    r->pos = r->len = 0;
 
     /* Reset task stack. */
     r->ridx = -1;
@@ -433,10 +431,11 @@ redisReader *redisReaderCreateWithFunctions(redisReplyObjectFunctions *fn) {
 }
 
 void redisReaderFree(redisReader *r) {
+    if (r == NULL)
+        return;
     if (r->reply != NULL && r->fn && r->fn->freeObject)
         r->fn->freeObject(r->reply);
-    if (r->buf != NULL)
-        sdsfree(r->buf);
+    sdsfree(r->buf);
     free(r);
 }