[libvirt] [PATCH 3/3] util: add backing store parser support for gluster protocol

[Prasanna Kumar Kalever]

This patch adds support for gluster specific JSON parser functionality

This  will help in parsing the backing store which uses JSON syntax and update
the meta-data in the domain specific objects while taking snapshots which inturn
helps in successful creation/updation of backing store information in domain xml

Signed-off-by: Prasanna Kumar Kalever <prasanna.kalever at redhat.com>
---
 src/util/virstoragefile.c | 130 ++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 130 insertions(+)

diff --git a/src/util/virstoragefile.c b/src/util/virstoragefile.c
index 2aa1d90..c122d3a 100644
--- a/src/util/virstoragefile.c
+++ b/src/util/virstoragefile.c
@@ -41,6 +41,7 @@
 #include "virstring.h"
 #include "virutil.h"
 #include "viruri.h"
+#include "virjson.h"
 #include "dirname.h"
 #include "virbuffer.h"
 
@@ -2124,6 +2125,132 @@ virStorageSourceNewFromBackingRelative(virStorageSourcePtr parent,
     goto cleanup;
 }
 
+static int
+virStorageSourceParseBackingJSON(virStorageSourcePtr src,
+        const char *path)
+{
+#if WITH_STORAGE_GLUSTER
+
+    virJSONValuePtr json = NULL;
+    virJSONValuePtr file = NULL;
+    virJSONValuePtr volfile_server = NULL;
+    char *transport = NULL;
+    int port = 0;
+    size_t i = 0;
+
+    /* The string may look like:
+     * json:{ file: { driver:"gluster", volname:"testvol", image-path:"/a.img",
+     * volfile-servers :[ {server:"1.2.3.4", port:24007, transport:"tcp"} ,
+     *                      {server:"5.6.7.8", port:24008, transport:"rdma"},
+     *                      {}, ... ] }, driver:"qcow2" }
+     */
+
+    json = virJSONValueFromString(path+strlen("json:"));
+
+    if (virJSONValueObjectHasKey(json, "driver")) {
+        if (!(src->format = virStorageFileFormatTypeFromString(
+                        virJSONValueObjectGetString(json, "driver")))) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                    _("Unable to get Format type of key 'driver' from JSON"));
+            goto error;
+        }
+    }
+
+    if (virJSONValueObjectHasKey(json, "file")) {
+        if (!(file = virJSONValueObjectGet(json, "file"))) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                    _("Unbale to get Object from key 'file'"));
+            goto error;
+        }
+    }
+
+    if (virJSONValueObjectHasKey(file, "driver")) {
+        if (!(src->protocol = virStorageNetProtocolTypeFromString(
+                        virJSONValueObjectGetString(file, "driver")))) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                    _("Unable to get Protocol type of key 'driver' from JSON"));
+            goto error;
+        }
+    }
+
+    if (virJSONValueObjectHasKey(file, "volname")) {
+        if (!(src->volume = (char *) virJSONValueObjectGetString(file,
+                        "volname"))) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                    _("Unbale to get String from key 'volname'"));
+            goto error;
+        }
+    }
+
+    if (virJSONValueObjectHasKey(file, "image-path")) {
+        if (!(src->path = (char *) virJSONValueObjectGetString(file,
+                        "image-path"))) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                    _("Unable to get String from key 'image-path'"));
+            goto error;
+        }
+    }
+
+    if (virJSONValueObjectHasKey(file, "volfile-servers")) {
+        if (!(src->nhosts = virJSONValueArraySize(virJSONValueObjectGet(file,
+                            "volfile-servers")))) {
+            virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                    _("Unable to get Size of Array of key 'volfile-servers'"));
+            goto error;
+        }
+    }
+
+    /* null-terminated list */
+    if (VIR_ALLOC_N(src->hosts, src->nhosts + 1) < 0)
+        goto error;
+
+    for (i = 0; i < src->nhosts; i++) {
+        volfile_server = virJSONValueArrayGet(virJSONValueObjectGetArray(file,
+                    "volfile-servers"), i);
+
+        if (virJSONValueObjectHasKey(volfile_server, "server")) {
+            if (VIR_STRDUP(src->hosts[i].name,
+                        virJSONValueObjectGetString(volfile_server, "server")) < 0) {
+                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                        _("Unable to get String from key 'server'"));
+                goto error;
+            }
+        }
+
+        if (virJSONValueObjectHasKey(volfile_server, "port")) {
+            if (virJSONValueObjectGetNumberInt(volfile_server, "port", &port) < 0) {
+                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                        _("Unable to get NumberInt from key 'port'"));
+                goto error;
+            }
+            if (virAsprintf(&src->hosts[i].port, "%d", port) < 0)
+                goto error;
+        }
+
+        if (virJSONValueObjectHasKey(volfile_server, "transport")) {
+            if (VIR_STRDUP(transport, virJSONValueObjectGetString(volfile_server,
+                            "transport")) < 0) {
+                virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+                        _("Unable to get String from key 'transport'"));
+                goto error;
+            }
+            src->hosts[i].transport = virStorageNetHostTransportTypeFromString(transport);
+            VIR_FREE(transport);
+        }
+    }
+
+    return 0;
+
+ error:
+    VIR_FREE(transport);
+    virJSONValueFree(volfile_server);
+    virJSONValueFree(file);
+    virJSONValueFree(json);
+
+#endif /* WITH_STORAGE_GLUSTER */
+
+    return -1;
+}
 
 static int
 virStorageSourceParseBackingURI(virStorageSourcePtr src,
@@ -2535,6 +2662,9 @@ virStorageSourceNewFromBackingAbsolute(const char *path)
         if (strstr(path, "://")) {
             if (virStorageSourceParseBackingURI(ret, path) < 0)
                 goto error;
+        } else if (strstr(path, "json:")) {
+            if (virStorageSourceParseBackingJSON(ret, path) < 0)
+                goto error;
         } else {
             if (virStorageSourceParseBackingColon(ret, path) < 0)
                 goto error;
-- 
2.1.0