Lock the OS thread when acessing errors

The library stores error information in thread-local storage, which
means we need to make sure that the Go runtime doesn't switch OS
threads between the time we call a function and th time we attempt to
retrieve the error information.

1 files changed, 11 insertions, 0 deletions

diff --git a/git.go b/git.go
index 6f81293..28196c8 100644
--- a/git.go
+++ b/git.go
@@ -9,6 +9,7 @@ import "C"
 import (
 	"bytes"
 	"errors"
+	"runtime"
 	"unsafe"
 	"strings"
 )
@@ -57,6 +58,9 @@ func NewOidFromString(s string) (*Oid, error) {
 	cs := C.CString(s)
 	defer C.free(unsafe.Pointer(cs))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	if C.git_oid_fromstr(o.toC(), cs) < 0 {
 		return nil, LastError()
 	}
@@ -109,6 +113,10 @@ func ShortenOids(ids []*Oid, minlen int) (int, error) {
 	defer C.git_oid_shorten_free(shorten)
 
 	var ret C.int
+
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	for _, id := range ids {
 		buf := make([]byte, 41)
 		C.git_oid_fmt((*C.char)(unsafe.Pointer(&buf[0])), id.toC())
@@ -162,6 +170,9 @@ func Discover(start string, across_fs bool, ceiling_dirs []string) (string, erro
 	retpath := (*C.char)(C.malloc(C.GIT_PATH_MAX))
 	defer C.free(unsafe.Pointer(retpath))
 
+	runtime.LockOSThread()
+	defer runtime.UnlockOSThread()
+
 	r := C.git_repository_discover(retpath, C.GIT_PATH_MAX, cstart, cbool(across_fs), ceildirs)
 
 	if r == 0 {