Merge pull request #337 from libgit2/cmn/go16-blob-pointer
Work around the finnicky 1.6 CGo pointer checks
diff --git a/.travis.yml b/.travis.yml
index f796389..79ad168 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -10,6 +10,8 @@
- 1.3
- 1.4
- 1.5
+ - 1.6
+ - 1.7
- tip
matrix:
diff --git a/blob.go b/blob.go
index 1a86e60..8b3e94f 100644
--- a/blob.go
+++ b/blob.go
@@ -37,15 +37,24 @@
defer runtime.UnlockOSThread()
var id C.git_oid
- var ptr unsafe.Pointer
+ var size C.size_t
+ // Go 1.6 added some increased checking of passing pointer to
+ // C, but its check depends on its expectations of waht we
+ // pass to the C function, so unless we take the address of
+ // its contents at the call site itself, it can fail when
+ // 'data' is a slice of a slice.
+ //
+ // When we're given an empty slice, create a dummy one where 0
+ // isn't out of bounds.
if len(data) > 0 {
- ptr = unsafe.Pointer(&data[0])
+ size = C.size_t(len(data))
} else {
- ptr = unsafe.Pointer(nil)
+ data = []byte{0}
+ size = C.size_t(0)
}
- ecode := C.git_blob_create_frombuffer(&id, repo.ptr, ptr, C.size_t(len(data)))
+ ecode := C.git_blob_create_frombuffer(&id, repo.ptr, unsafe.Pointer(&data[0]), size)
if ecode < 0 {
return nil, MakeGitError(ecode)
}
diff --git a/blob_test.go b/blob_test.go
index 2b5ec4f..6b7cd49 100644
--- a/blob_test.go
+++ b/blob_test.go
@@ -1,9 +1,21 @@
package git
import (
+ "bytes"
"testing"
)
+type bufWrapper struct {
+ buf [64]byte
+ pointer []byte
+}
+
+func doublePointerBytes() []byte {
+ o := &bufWrapper{}
+ o.pointer = o.buf[0:10]
+ return o.pointer[0:1]
+}
+
func TestCreateBlobFromBuffer(t *testing.T) {
repo := createTestRepo(t)
defer cleanupTestRepo(t, repo)
@@ -14,4 +26,16 @@
if id.String() != "e69de29bb2d1d6434b8b29ae775ad8c2e48c5391" {
t.Fatal("Empty buffer did not deliver empty blob id")
}
+
+ for _, data := range []([]byte){[]byte("hello there"), doublePointerBytes()} {
+ id, err = repo.CreateBlobFromBuffer(data)
+ checkFatal(t, err)
+
+ blob, err := repo.LookupBlob(id)
+ checkFatal(t, err)
+ if !bytes.Equal(blob.Contents(), data) {
+ t.Fatal("Loaded bytes don't match original bytes:",
+ blob.Contents(), "!=", data)
+ }
+ }
}
