Re: [libvirt] [PATCH] util: avoid symbol clash between json libraries

The jansson and json-glib libraries both export symbols with a json_ name prefix and json_object_iter_next() clashes between them. Unfortunately json_glib is linked in by GTK, so any app using GTK and libvirt will get a clash, resulting in SEGV. This also affects the NSS module provided by libvirt Instead of directly linking to jansson, use dlopen() with the RTLD_LOCAL flag which allows us to hide the symbols from the application that loads libvirt or the NSS module. Some preprocessor black magic and wrapper functions are used to redirect calls into the dlopen resolved symbols. Signed-off-by: Daniel P. Berrangé <berrange(a)redhat.com&gt; --- libvirt.spec.in | 2 + src/Makefile.am | 3 + src/util/Makefile.inc.am | 3 +- src/util/virjson.c | 9 +- src/util/virjsoncompat.c | 253 +++++++++++++++++++++++++++++++++++++++ src/util/virjsoncompat.h | 86 +++++++++++++ 6 files changed, 354 insertions(+), 2 deletions(-) create mode 100644 src/util/virjsoncompat.c create mode 100644 src/util/virjsoncompat.h

diff --git a/src/util/virjson.c b/src/util/virjson.c index 01a387b2f7..5bab662cd3 100644 --- a/src/util/virjson.c +++ b/src/util/virjson.c @@ -1437,7 +1437,8 @@ virJSONValueCopy(const virJSONValue *in) #if WITH_JANSSON -# include <jansson.h> + +# include "virjsoncompat.h" static virJSONValuePtr virJSONValueFromJansson(json_t *json) @@ -1524,6 +1525,9 @@ virJSONValueFromString(const char *jsonstring) size_t flags = JSON_REJECT_DUPLICATES | JSON_DECODE_ANY; + if (virJSONInitialize() < 0) + return NULL; + if (!(json = json_loads(jsonstring, flags, &error))) { virReportError(VIR_ERR_INTERNAL_ERROR, _("failed to parse JSON %d:%d: %s"), @@ -1630,6 +1634,9 @@ virJSONValueToString(virJSONValuePtr object, json_t *json; char *str = NULL; + if (virJSONInitialize() < 0) + return NULL; + if (pretty) flags |= JSON_INDENT(2); else