From: Joel Rosdahl <joel@rosdahl.net>
Date: Sun, 22 Sep 2019 17:46:42 +0000 (+0200)
Subject: Don’t crash if localtime returns null pointer in localtime_r replacement
X-Git-Tag: v4.0~781
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=87550e9c38560fa28b8d36753de18f980811a421;p=thirdparty%2Fccache.git

Don’t crash if localtime returns null pointer in localtime_r replacement

This seems to happen in some unknown Windows environment, see #450.

Fixes #450.

(cherry picked from commit 8c4ffbab96a8f4bebc27b39ad3a235a5d8baeab3)
---

diff --git a/src/hashutil.cpp b/src/hashutil.cpp
index d3a997407..93317522c 100644
--- a/src/hashutil.cpp
+++ b/src/hashutil.cpp
@@ -88,13 +88,16 @@ hash_source_code_string(const Config& config,
   hash_string_buffer(hash, str, len);
 
   if (result & HASH_SOURCE_CODE_FOUND_DATE) {
+    cc_log("Found __DATE__ in %s", path);
+
     // Make sure that the hash sum changes if the (potential) expansion of
     // __DATE__ changes.
     time_t t = time(NULL);
     struct tm now;
-    localtime_r(&t, &now);
-    cc_log("Found __DATE__ in %s", path);
     hash_delimiter(hash, "date");
+    if (!localtime_r(&t, &now)) {
+      return HASH_SOURCE_CODE_ERROR;
+    }
     hash_int(hash, now.tm_year);
     hash_int(hash, now.tm_mon);
     hash_int(hash, now.tm_mday);
diff --git a/src/util.cpp b/src/util.cpp
index 978cd227e..7948938ba 100644
--- a/src/util.cpp
+++ b/src/util.cpp
@@ -1134,8 +1134,13 @@ struct tm*
 localtime_r(const time_t* timep, struct tm* result)
 {
   struct tm* tm = localtime(timep);
-  *result = *tm;
-  return result;
+  if (tm) {
+    *result = *tm;
+    return result;
+  } else {
+    memset(result, 0, sizeof(*result));
+    return NULL;
+  }
 }
 #endif