SystemProperties.set(): more exception message detail.
Bug: https://issuetracker.google.com/336223505
Change-Id: I5bbee1c036565d117e95941b8751f26494390be0
diff --git a/core/jni/android_os_SystemProperties.cpp b/core/jni/android_os_SystemProperties.cpp
index 7f3b32e..88e6fa3 100644
--- a/core/jni/android_os_SystemProperties.cpp
+++ b/core/jni/android_os_SystemProperties.cpp
@@ -190,15 +190,31 @@
return;
}
}
+ // Calling SystemProperties.set() with a null value is equivalent to an
+ // empty string, but this is not true for the underlying libc function.
+ const char* value_c_str = value ? value->c_str() : "";
+ // Explicitly clear errno so we can recognize __system_property_set()
+ // failures from failed system calls (as opposed to "init rejected your
+ // request" failures).
+ errno = 0;
bool success;
#if defined(__BIONIC__)
- success = !__system_property_set(key.c_str(), value ? value->c_str() : "");
+ success = !__system_property_set(key.c_str(), value_c_str);
#else
- success = android::base::SetProperty(key.c_str(), value ? value->c_str() : "");
+ success = android::base::SetProperty(key.c_str(), value_c_str);
#endif
if (!success) {
- jniThrowException(env, "java/lang/RuntimeException",
- "failed to set system property (check logcat for reason)");
+ if (errno != 0) {
+ jniThrowExceptionFmt(env, "java/lang/RuntimeException",
+ "failed to set system property \"%s\" to \"%s\": %m",
+ key.c_str(), value_c_str);
+ } else {
+ // Must have made init unhappy, which will have logged something,
+ // but there's no API to ask for more detail.
+ jniThrowExceptionFmt(env, "java/lang/RuntimeException",
+ "failed to set system property \"%s\" to \"%s\" (check logcat for reason)",
+ key.c_str(), value_c_str);
+ }
}
}