From f6035a5ec8045bf007c7ebc5ee5306418644e7aa Mon Sep 17 00:00:00 2001 From: David Herrmann Date: Wed, 15 Jul 2015 12:30:08 +0200 Subject: [PATCH] sd-device: never return NULL+0 It is highly confusing if a getter function returns 0, but the value is set to NULL. This, right now, triggers assertions as code relies on the returned values to be non-NULL. Like with sd-bus-creds and friends, return 0 only if a value is actually available. Discussed with Tom, and actually fixes real bugs as in #512. --- src/libelogind/sd-device/sd-device.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/src/libelogind/sd-device/sd-device.c b/src/libelogind/sd-device/sd-device.c index b274f7109..7cea5a074 100644 --- a/src/libelogind/sd-device/sd-device.c +++ b/src/libelogind/sd-device/sd-device.c @@ -791,6 +791,9 @@ _public_ int sd_device_get_subsystem(sd_device *device, const char **ret) { device->subsystem_set = true; } + if (!device->subsystem) + return -ENOENT; + *ret = device->subsystem; return 0; @@ -908,6 +911,9 @@ _public_ int sd_device_get_driver(sd_device *device, const char **ret) { return log_debug_errno(r, "sd-device: could not set driver for %s: %m", device->devpath); } + if (!device->driver) + return -ENOENT; + *ret = device->driver; return 0; @@ -1002,6 +1008,8 @@ _public_ int sd_device_get_sysname(sd_device *device, const char **ret) { return r; } + assert_return(device->sysname, -ENOENT); + *ret = device->sysname; return 0; -- 2.30.2