rebase: Support preserving merges in non-interactive mode

diff --git a/builtin-merge-file.c b/builtin-merge-file.c
index adce6d4635a4153428368073677cd74a9bafc045..45c98538cdbf35352f7a3b5adf40fca9d7512ea5 100644 (file)
--- a/builtin-merge-file.c
+++ b/builtin-merge-file.c
@@ -4,7 +4,7 @@
 #include "xdiff-interface.h"
 
 static const char merge_file_usage[] =
-"git merge-file [-p | --stdout] [-q | --quiet] [-L name1 [-L orig [-L name2]]] file1 orig_file file2";
+"git merge-file [-p | --stdout] [--diff3] [-q | --quiet] [-L name1 [-L orig [-L name2]]] file1 orig_file file2";
 
 int cmd_merge_file(int argc, const char **argv, const char *prefix)
 {
@@ -13,6 +13,17 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
        mmbuffer_t result = {NULL, 0};
        xpparam_t xpp = {XDF_NEED_MINIMAL};
        int ret = 0, i = 0, to_stdout = 0;
+       int merge_level = XDL_MERGE_ZEALOUS_ALNUM;
+       int merge_style = 0;
+       int nongit;
+
+       prefix = setup_git_directory_gently(&nongit);
+       if (!nongit) {
+               /* Read the configuration file */
+               git_config(git_xmerge_config, NULL);
+               if (0 <= git_xmerge_style)
+                       merge_style = git_xmerge_style;
+       }
 
        while (argc > 4) {
                if (!strcmp(argv[1], "-L") && i < 3) {
@@ -25,6 +36,8 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
                else if (!strcmp(argv[1], "-q") ||
                                !strcmp(argv[1], "--quiet"))
                        freopen("/dev/null", "w", stderr);
+               else if (!strcmp(argv[1], "--diff3"))
+                       merge_style = XDL_MERGE_DIFF3;
                else
                        usage(merge_file_usage);
                argc--;
@@ -46,7 +59,7 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
        }
 
        ret = xdl_merge(mmfs + 1, mmfs + 0, names[0], mmfs + 2, names[2],
-                       &xpp, XDL_MERGE_ZEALOUS_ALNUM, &result);
+                       &xpp, merge_level | merge_style, &result);
 
        for (i = 0; i < 3; i++)
                free(mmfs[i].ptr);
@@ -57,7 +70,8 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
 
                if (!f)
                        ret = error("Could not open %s for writing", filename);
-               else if (fwrite(result.ptr, result.size, 1, f) != 1)
+               else if (result.size &&
+                        fwrite(result.ptr, result.size, 1, f) != 1)
                        ret = error("Could not write to %s", filename);
                else if (fclose(f))
                        ret = error("Could not close %s", filename);