[Qemu-devel] [PATCH v3 18/24] vmdk: Clean up "Invalid extent lines" error message

[Markus Armbruster <armbru@redhat.com>]

vmdk_parse_extents() reports parse errors like this:

    error_setg(errp, "Invalid extent lines:\n%s", p);

where p points to the beginning of the malformed line in the image
descriptor.  This results in a multi-line error message

    Invalid extent lines:
    <first line that doesn't parse>
    <remaining text that may or may not parse, if any>

Error messages should not have newlines embedded.  Since the remaining
text is not helpful, we can simply report:

    Invalid extent line: <first line that doesn't parse>

Cc: Fam Zheng <famz@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
---
 block/vmdk.c               | 20 +++++++++++++-------
 tests/qemu-iotests/059.out |  4 +---
 2 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/block/vmdk.c b/block/vmdk.c
index 08fa3f3..2b5cb00 100644
--- a/block/vmdk.c
+++ b/block/vmdk.c
@@ -780,7 +780,7 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
     char access[11];
     char type[11];
     char fname[512];
-    const char *p;
+    const char *p, *np;
     int64_t sectors = 0;
     int64_t flat_offset;
     char *extent_path;
@@ -805,19 +805,16 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
             continue;
         } else if (!strcmp(type, "FLAT")) {
             if (matches != 5 || flat_offset < 0) {
-                error_setg(errp, "Invalid extent lines: \n%s", p);
-                return -EINVAL;
+                goto invalid;
             }
         } else if (!strcmp(type, "VMFS")) {
             if (matches == 4) {
                 flat_offset = 0;
             } else {
-                error_setg(errp, "Invalid extent lines:\n%s", p);
-                return -EINVAL;
+                goto invalid;
             }
         } else if (matches != 4) {
-            error_setg(errp, "Invalid extent lines:\n%s", p);
-            return -EINVAL;
+            goto invalid;
         }
 
         if (sectors <= 0 ||
@@ -883,6 +880,15 @@ static int vmdk_parse_extents(const char *desc, BlockDriverState *bs,
         extent->type = g_strdup(type);
     }
     return 0;
+
+invalid:
+    np = next_line(p);
+    assert(np != p);
+    if (np[-1] == '\n') {
+        np--;
+    }
+    error_setg(errp, "Invalid extent line: %.*s", (int)(np - p), p);
+    return -EINVAL;
 }
 
 static int vmdk_open_desc_file(BlockDriverState *bs, int flags, char *buf,
diff --git a/tests/qemu-iotests/059.out b/tests/qemu-iotests/059.out
index d28df5b..9d506cb 100644
--- a/tests/qemu-iotests/059.out
+++ b/tests/qemu-iotests/059.out
@@ -2038,9 +2038,7 @@ Format specific information:
             format: FLAT
 
 === Testing malformed VMFS extent description line ===
-qemu-img: Could not open 'TEST_DIR/t.IMGFMT': Invalid extent lines:
-RW 12582912 VMFS "dummy.IMGFMT" 1
-
+qemu-img: Could not open 'TEST_DIR/t.IMGFMT': Invalid extent line: RW 12582912 VMFS "dummy.IMGFMT" 1
 
 === Testing truncated sparse ===
 Formatting 'TEST_DIR/t.IMGFMT', fmt=IMGFMT size=107374182400 subformat=monolithicSparse
-- 
2.4.3