block/qapi: Clean up how we print to monitor or stdout

bdrv_snapshot_dump(), bdrv_image_info_specific_dump(),
bdrv_image_info_dump() and their helpers take an fprintf()-like
callback and a FILE * to pass to it.

hmp.c passes monitor_printf() cast to fprintf_function and the current
monitor cast to FILE *.

qemu-img.c and qemu-io-cmds.c pass fprintf and stdout.

The type-punning is technically undefined behaviour, but works in
practice.  Clean up: drop the callback, and call qemu_printf()
instead.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Message-Id: <20190417191805.28198-8-armbru@redhat.com>

block/qapi.c

@@ -36,6 +36,7 @@
 #include "qapi/qmp/qlist.h"
 #include "qapi/qmp/qnum.h"
 #include "qapi/qmp/qstring.h"
+#include "qemu/qemu-print.h"
 #include "sysemu/block-backend.h"
 #include "qemu/cutils.h"
 
@@ -660,8 +661,7 @@ static char *get_human_readable_size(char *buf, int buf_size, int64_t size)
     return buf;
 }
 
-void bdrv_snapshot_dump(fprintf_function func_fprintf, void *f,
-                        QEMUSnapshotInfo *sn)
+void bdrv_snapshot_dump(QEMUSnapshotInfo *sn)
 {
     char buf1[128], date_buf[128], clock_buf[128];
     struct tm tm;
@@ -669,9 +669,8 @@ void bdrv_snapshot_dump(fprintf_function func_fprintf, void *f,
     int64_t secs;
 
     if (!sn) {
-        func_fprintf(f,
-                     "%-10s%-20s%7s%20s%15s",
-                     "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
+        qemu_printf("%-10s%-20s%7s%20s%15s",
+                    "ID", "TAG", "VM SIZE", "DATE", "VM CLOCK");
     } else {
         ti = sn->date_sec;
         localtime_r(&ti, &tm);
@@ -684,50 +683,46 @@ void bdrv_snapshot_dump(fprintf_function func_fprintf, void *f,
                  (int)((secs / 60) % 60),
                  (int)(secs % 60),
                  (int)((sn->vm_clock_nsec / 1000000) % 1000));
-        func_fprintf(f,
-                     "%-10s%-20s%7s%20s%15s",
-                     sn->id_str, sn->name,
-                     get_human_readable_size(buf1, sizeof(buf1),
-                                             sn->vm_state_size),
-                     date_buf,
-                     clock_buf);
+        qemu_printf("%-10s%-20s%7s%20s%15s",
+                    sn->id_str, sn->name,
+                    get_human_readable_size(buf1, sizeof(buf1),
+                                            sn->vm_state_size),
+                    date_buf,
+                    clock_buf);
     }
 }
 
-static void dump_qdict(fprintf_function func_fprintf, void *f, int indentation,
-                       QDict *dict);
-static void dump_qlist(fprintf_function func_fprintf, void *f, int indentation,
-                       QList *list);
+static void dump_qdict(int indentation, QDict *dict);
+static void dump_qlist(int indentation, QList *list);
 
-static void dump_qobject(fprintf_function func_fprintf, void *f,
-                         int comp_indent, QObject *obj)
+static void dump_qobject(int comp_indent, QObject *obj)
 {
     switch (qobject_type(obj)) {
         case QTYPE_QNUM: {
             QNum *value = qobject_to(QNum, obj);
             char *tmp = qnum_to_string(value);
-            func_fprintf(f, "%s", tmp);
+            qemu_printf("%s", tmp);
             g_free(tmp);
             break;
         }
         case QTYPE_QSTRING: {
             QString *value = qobject_to(QString, obj);
-            func_fprintf(f, "%s", qstring_get_str(value));
+            qemu_printf("%s", qstring_get_str(value));
             break;
         }
         case QTYPE_QDICT: {
             QDict *value = qobject_to(QDict, obj);
-            dump_qdict(func_fprintf, f, comp_indent, value);
+            dump_qdict(comp_indent, value);
             break;
         }
         case QTYPE_QLIST: {
             QList *value = qobject_to(QList, obj);
-            dump_qlist(func_fprintf, f, comp_indent, value);
+            dump_qlist(comp_indent, value);
             break;
         }
         case QTYPE_QBOOL: {
             QBool *value = qobject_to(QBool, obj);
-            func_fprintf(f, "%s", qbool_get_bool(value) ? "true" : "false");
+            qemu_printf("%s", qbool_get_bool(value) ? "true" : "false");
             break;
         }
         default:
@@ -735,8 +730,7 @@ static void dump_qobject(fprintf_function func_fprintf, void *f,
     }
 }
 
-static void dump_qlist(fprintf_function func_fprintf, void *f, int indentation,
-                       QList *list)
+static void dump_qlist(int indentation, QList *list)
 {
     const QListEntry *entry;
     int i = 0;
@@ -744,17 +738,16 @@ static void dump_qlist(fprintf_function func_fprintf, void *f, int indentation,
     for (entry = qlist_first(list); entry; entry = qlist_next(entry), i++) {
         QType type = qobject_type(entry->value);
         bool composite = (type == QTYPE_QDICT || type == QTYPE_QLIST);
-        func_fprintf(f, "%*s[%i]:%c", indentation * 4, "", i,
-                     composite ? '\n' : ' ');
-        dump_qobject(func_fprintf, f, indentation + 1, entry->value);
+        qemu_printf("%*s[%i]:%c", indentation * 4, "", i,
+                    composite ? '\n' : ' ');
+        dump_qobject(indentation + 1, entry->value);
         if (!composite) {
-            func_fprintf(f, "\n");
+            qemu_printf("\n");
         }
     }
 }
 
-static void dump_qdict(fprintf_function func_fprintf, void *f, int indentation,
-                       QDict *dict)
+static void dump_qdict(int indentation, QDict *dict)
 {
     const QDictEntry *entry;
 
@@ -769,18 +762,17 @@ static void dump_qdict(fprintf_function func_fprintf, void *f, int indentation,
             key[i] = entry->key[i] == '-' ? ' ' : entry->key[i];
         }
         key[i] = 0;
-        func_fprintf(f, "%*s%s:%c", indentation * 4, "", key,
-                     composite ? '\n' : ' ');
-        dump_qobject(func_fprintf, f, indentation + 1, entry->value);
+        qemu_printf("%*s%s:%c", indentation * 4, "", key,
+                    composite ? '\n' : ' ');
+        dump_qobject(indentation + 1, entry->value);
         if (!composite) {
-            func_fprintf(f, "\n");
+            qemu_printf("\n");
         }
         g_free(key);
     }
 }
 
-void bdrv_image_info_specific_dump(fprintf_function func_fprintf, void *f,
-                                   ImageInfoSpecific *info_spec)
+void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec)
 {
     QObject *obj, *data;
     Visitor *v = qobject_output_visitor_new(&obj);
@@ -788,13 +780,12 @@ void bdrv_image_info_specific_dump(fprintf_function func_fprintf, void *f,
     visit_type_ImageInfoSpecific(v, NULL, &info_spec, &error_abort);
     visit_complete(v, &obj);
     data = qdict_get(qobject_to(QDict, obj), "data");
-    dump_qobject(func_fprintf, f, 1, data);
+    dump_qobject(1, data);
     qobject_unref(obj);
     visit_free(v);
 }
 
-void bdrv_image_info_dump(fprintf_function func_fprintf, void *f,
-                          ImageInfo *info)
+void bdrv_image_info_dump(ImageInfo *info)
 {
     char size_buf[128], dsize_buf[128];
     if (!info->has_actual_size) {
@@ -804,49 +795,48 @@ void bdrv_image_info_dump(fprintf_function func_fprintf, void *f,
                                 info->actual_size);
     }
     get_human_readable_size(size_buf, sizeof(size_buf), info->virtual_size);
-    func_fprintf(f,
-                 "image: %s\n"
-                 "file format: %s\n"
-                 "virtual size: %s (%" PRId64 " bytes)\n"
-                 "disk size: %s\n",
-                 info->filename, info->format, size_buf,
-                 info->virtual_size,
-                 dsize_buf);
+    qemu_printf("image: %s\n"
+                "file format: %s\n"
+                "virtual size: %s (%" PRId64 " bytes)\n"
+                "disk size: %s\n",
+                info->filename, info->format, size_buf,
+                info->virtual_size,
+                dsize_buf);
 
     if (info->has_encrypted && info->encrypted) {
-        func_fprintf(f, "encrypted: yes\n");
+        qemu_printf("encrypted: yes\n");
     }
 
     if (info->has_cluster_size) {
-        func_fprintf(f, "cluster_size: %" PRId64 "\n",
-                       info->cluster_size);
+        qemu_printf("cluster_size: %" PRId64 "\n",
+                    info->cluster_size);
     }
 
     if (info->has_dirty_flag && info->dirty_flag) {
-        func_fprintf(f, "cleanly shut down: no\n");
+        qemu_printf("cleanly shut down: no\n");
     }
 
     if (info->has_backing_filename) {
-        func_fprintf(f, "backing file: %s", info->backing_filename);
+        qemu_printf("backing file: %s", info->backing_filename);
         if (!info->has_full_backing_filename) {
-            func_fprintf(f, " (cannot determine actual path)");
+            qemu_printf(" (cannot determine actual path)");
         } else if (strcmp(info->backing_filename,
                           info->full_backing_filename) != 0) {
-            func_fprintf(f, " (actual path: %s)", info->full_backing_filename);
+            qemu_printf(" (actual path: %s)", info->full_backing_filename);
         }
-        func_fprintf(f, "\n");
+        qemu_printf("\n");
         if (info->has_backing_filename_format) {
-            func_fprintf(f, "backing file format: %s\n",
-                         info->backing_filename_format);
+            qemu_printf("backing file format: %s\n",
+                        info->backing_filename_format);
         }
     }
 
     if (info->has_snapshots) {
         SnapshotInfoList *elem;
 
-        func_fprintf(f, "Snapshot list:\n");
-        bdrv_snapshot_dump(func_fprintf, f, NULL);
-        func_fprintf(f, "\n");
+        qemu_printf("Snapshot list:\n");
+        bdrv_snapshot_dump(NULL);
+        qemu_printf("\n");
 
         /* Ideally bdrv_snapshot_dump() would operate on SnapshotInfoList but
          * we convert to the block layer's native QEMUSnapshotInfo for now.
@@ -862,13 +852,13 @@ void bdrv_image_info_dump(fprintf_function func_fprintf, void *f,
 
             pstrcpy(sn.id_str, sizeof(sn.id_str), elem->value->id);
             pstrcpy(sn.name, sizeof(sn.name), elem->value->name);
-            bdrv_snapshot_dump(func_fprintf, f, &sn);
-            func_fprintf(f, "\n");
+            bdrv_snapshot_dump(&sn);
+            qemu_printf("\n");
         }
     }
 
     if (info->has_format_specific) {
-        func_fprintf(f, "Format specific information:\n");
-        bdrv_image_info_specific_dump(func_fprintf, f, info->format_specific);
+        qemu_printf("Format specific information:\n");
+        bdrv_image_info_specific_dump(info->format_specific);
     }
 }

hmp.c

@@ -580,8 +580,7 @@ static void print_block_info(Monitor *mon, BlockInfo *info,
         monitor_printf(mon, "\nImages:\n");
         image_info = inserted->image;
         while (1) {
-                bdrv_image_info_dump((fprintf_function)monitor_printf,
-                                     mon, image_info);
+                bdrv_image_info_dump(image_info);
             if (image_info->has_backing_image) {
                 image_info = image_info->backing_image;
             } else {
@@ -1586,7 +1585,7 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
     monitor_printf(mon, "List of snapshots present on all disks:\n");
 
     if (total > 0) {
-        bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL);
+        bdrv_snapshot_dump(NULL);
         monitor_printf(mon, "\n");
         for (i = 0; i < total; i++) {
             sn = &sn_tab[global_snapshots[i]];
@@ -1594,7 +1593,7 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
              * overwrite it.
              */
             pstrcpy(sn->id_str, sizeof(sn->id_str), "--");
-            bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, sn);
+            bdrv_snapshot_dump(sn);
             monitor_printf(mon, "\n");
         }
     } else {
@@ -1608,11 +1607,10 @@ void hmp_info_snapshots(Monitor *mon, const QDict *qdict)
         monitor_printf(mon,
                        "\nList of partial (non-loadable) snapshots on '%s':\n",
                        image_entry->imagename);
-        bdrv_snapshot_dump((fprintf_function)monitor_printf, mon, NULL);
+        bdrv_snapshot_dump(NULL);
         monitor_printf(mon, "\n");
         QTAILQ_FOREACH(snapshot_entry, &image_entry->snapshots, next) {
-            bdrv_snapshot_dump((fprintf_function)monitor_printf, mon,
-                               &snapshot_entry->sn);
+            bdrv_snapshot_dump(&snapshot_entry->sn);
             monitor_printf(mon, "\n");
         }
     }

include/block/qapi.h

@@ -27,7 +27,6 @@
 
 #include "block/block.h"
 #include "block/snapshot.h"
-#include "qemu/fprintf-fn.h"
 
 BlockDeviceInfo *bdrv_block_device_info(BlockBackend *blk,
                                         BlockDriverState *bs, Error **errp);
@@ -38,10 +37,7 @@ void bdrv_query_image_info(BlockDriverState *bs,
                            ImageInfo **p_info,
                            Error **errp);
 
-void bdrv_snapshot_dump(fprintf_function func_fprintf, void *f,
-                        QEMUSnapshotInfo *sn);
-void bdrv_image_info_specific_dump(fprintf_function func_fprintf, void *f,
-                                   ImageInfoSpecific *info_spec);
-void bdrv_image_info_dump(fprintf_function func_fprintf, void *f,
-                          ImageInfo *info);
+void bdrv_snapshot_dump(QEMUSnapshotInfo *sn);
+void bdrv_image_info_specific_dump(ImageInfoSpecific *info_spec);
+void bdrv_image_info_dump(ImageInfo *info);
 #endif

qemu-img.c

@@ -2483,11 +2483,11 @@ static void dump_snapshots(BlockDriverState *bs)
     if (nb_sns <= 0)
         return;
     printf("Snapshot list:\n");
-    bdrv_snapshot_dump(fprintf, stdout, NULL);
+    bdrv_snapshot_dump(NULL);
     printf("\n");
     for(i = 0; i < nb_sns; i++) {
         sn = &sn_tab[i];
-        bdrv_snapshot_dump(fprintf, stdout, sn);
+        bdrv_snapshot_dump(sn);
         printf("\n");
     }
     g_free(sn_tab);
@@ -2536,7 +2536,7 @@ static void dump_human_image_info_list(ImageInfoList *list)
         }
         delim = true;
 
-        bdrv_image_info_dump(fprintf, stdout, elem->value);
+        bdrv_image_info_dump(elem->value);
     }
 }
 

qemu-io-cmds.c

@@ -1699,7 +1699,7 @@ static int info_f(BlockBackend *blk, int argc, char **argv)
     }
     if (spec_info) {
         printf("Format specific information:\n");
-        bdrv_image_info_specific_dump(fprintf, stdout, spec_info);
+        bdrv_image_info_specific_dump(spec_info);
         qapi_free_ImageInfoSpecific(spec_info);
     }