xdiff: refactor a function

[thirdparty/git.git] / xdiff / xmerge.c

diff --git a/xdiff/xmerge.c b/xdiff/xmerge.c
index fff0b594f9a851a8e1a6fca961692614ff0c822a..d43abe05b95c458a0df6ce35c8b878c454be7a1c 100644 (file)
--- a/xdiff/xmerge.c
+++ b/xdiff/xmerge.c
@@ -684,35 +684,30 @@ static int xdl_do_merge(xdfenv_t *xe1, xdchange_t *xscr1,
 int xdl_merge(mmfile_t *orig, mmfile_t *mf1, mmfile_t *mf2,
                xmparam_t const *xmp, mmbuffer_t *result)
 {
-       xdchange_t *xscr1, *xscr2;
+       xdchange_t *xscr1 = NULL, *xscr2 = NULL;
        xdfenv_t xe1, xe2;
-       int status;
+       int status = -1;
        xpparam_t const *xpp = &xmp->xpp;
 
        result->ptr = NULL;
        result->size = 0;
 
-       if (xdl_do_diff(orig, mf1, xpp, &xe1) < 0) {
+       if (xdl_do_diff(orig, mf1, xpp, &xe1) < 0)
                return -1;
-       }
-       if (xdl_do_diff(orig, mf2, xpp, &xe2) < 0) {
-               xdl_free_env(&xe1);
-               return -1;
-       }
+
+       if (xdl_do_diff(orig, mf2, xpp, &xe2) < 0)
+               goto free_xe1; /* avoid double free of xe2 */
+
        if (xdl_change_compact(&xe1.xdf1, &xe1.xdf2, xpp->flags) < 0 ||
            xdl_change_compact(&xe1.xdf2, &xe1.xdf1, xpp->flags) < 0 ||
-           xdl_build_script(&xe1, &xscr1) < 0) {
-               xdl_free_env(&xe1);
-               return -1;
-       }
+           xdl_build_script(&xe1, &xscr1) < 0)
+               goto out;
+
        if (xdl_change_compact(&xe2.xdf1, &xe2.xdf2, xpp->flags) < 0 ||
            xdl_change_compact(&xe2.xdf2, &xe2.xdf1, xpp->flags) < 0 ||
-           xdl_build_script(&xe2, &xscr2) < 0) {
-               xdl_free_script(xscr1);
-               xdl_free_env(&xe1);
-               xdl_free_env(&xe2);
-               return -1;
-       }
+           xdl_build_script(&xe2, &xscr2) < 0)
+               goto out;
+
        status = 0;
        if (!xscr1) {
                result->ptr = xdl_malloc(mf2->size);
@@ -727,11 +722,13 @@ int xdl_merge(mmfile_t *orig, mmfile_t *mf1, mmfile_t *mf2,
                                      &xe2, xscr2,
                                      xmp, result);
        }
+ out:
        xdl_free_script(xscr1);
        xdl_free_script(xscr2);
 
-       xdl_free_env(&xe1);
        xdl_free_env(&xe2);
+ free_xe1:
+       xdl_free_env(&xe1);
 
        return status;
 }