git-am: Add am.keepcr and --no-keep-cr to override it
[gitweb.git] / builtin-merge-recursive.c
index b9738655adc66386e55eccafa9ab891bdcf30960..d8875d589240e0c78a9e241a7d2bdde1d10ab800 100644 (file)
-/*
- * Recursive Merge algorithm stolen from git-merge-recursive.py by
- * Fredrik Kuivinen.
- * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
- */
 #include "cache.h"
-#include "cache-tree.h"
 #include "commit.h"
-#include "blob.h"
-#include "builtin.h"
-#include "tree-walk.h"
-#include "diff.h"
-#include "diffcore.h"
 #include "tag.h"
-#include "unpack-trees.h"
-#include "string-list.h"
-#include "xdiff-interface.h"
-#include "ll-merge.h"
-#include "interpolate.h"
-#include "attr.h"
-#include "dir.h"
 #include "merge-recursive.h"
 
-static int subtree_merge;
-
-static struct tree *shift_tree_object(struct tree *one, struct tree *two)
-{
-       unsigned char shifted[20];
-
-       /*
-        * NEEDSWORK: this limits the recursion depth to hardcoded
-        * value '2' to avoid excessive overhead.
-        */
-       shift_tree(one->object.sha1, two->object.sha1, shifted, 2);
-       if (!hashcmp(two->object.sha1, shifted))
-               return two;
-       return lookup_tree(shifted);
-}
-
-/*
- * A virtual commit has
- * - (const char *)commit->util set to the name, and
- * - *(int *)commit->object.sha1 set to the virtual id.
- */
-
-static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
-{
-       struct commit *commit = xcalloc(1, sizeof(struct commit));
-       static unsigned virtual_id = 1;
-       commit->tree = tree;
-       commit->util = (void*)comment;
-       *(int*)commit->object.sha1 = virtual_id++;
-       /* avoid warnings */
-       commit->object.parsed = 1;
-       return commit;
-}
-
-/*
- * Since we use get_tree_entry(), which does not put the read object into
- * the object pool, we cannot rely on a == b.
- */
-static int sha_eq(const unsigned char *a, const unsigned char *b)
-{
-       if (!a && !b)
-               return 2;
-       return a && b && hashcmp(a, b) == 0;
-}
-
-/*
- * Since we want to write the index eventually, we cannot reuse the index
- * for these (temporary) data.
- */
-struct stage_data
-{
-       struct
-       {
-               unsigned mode;
-               unsigned char sha[20];
-       } stages[4];
-       unsigned processed:1;
-};
-
-static struct string_list current_file_set = {NULL, 0, 0, 1};
-static struct string_list current_directory_set = {NULL, 0, 0, 1};
-
-static int call_depth = 0;
-static int verbosity = 2;
-static int diff_rename_limit = -1;
-static int merge_rename_limit = -1;
-static int buffer_output = 1;
-static struct strbuf obuf = STRBUF_INIT;
-
-static int show(int v)
-{
-       return (!call_depth && verbosity >= v) || verbosity >= 5;
-}
-
-static void flush_output(void)
-{
-       if (obuf.len) {
-               fputs(obuf.buf, stdout);
-               strbuf_reset(&obuf);
-       }
-}
-
-static void output(int v, const char *fmt, ...)
-{
-       int len;
-       va_list ap;
-
-       if (!show(v))
-               return;
-
-       strbuf_grow(&obuf, call_depth * 2 + 2);
-       memset(obuf.buf + obuf.len, ' ', call_depth * 2);
-       strbuf_setlen(&obuf, obuf.len + call_depth * 2);
-
-       va_start(ap, fmt);
-       len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
-       va_end(ap);
-
-       if (len < 0)
-               len = 0;
-       if (len >= strbuf_avail(&obuf)) {
-               strbuf_grow(&obuf, len + 2);
-               va_start(ap, fmt);
-               len = vsnprintf(obuf.buf + obuf.len, strbuf_avail(&obuf), fmt, ap);
-               va_end(ap);
-               if (len >= strbuf_avail(&obuf)) {
-                       die("this should not happen, your snprintf is broken");
-               }
-       }
-       strbuf_setlen(&obuf, obuf.len + len);
-       strbuf_add(&obuf, "\n", 1);
-       if (!buffer_output)
-               flush_output();
-}
-
-static void output_commit_title(struct commit *commit)
-{
-       int i;
-       flush_output();
-       for (i = call_depth; i--;)
-               fputs("  ", stdout);
-       if (commit->util)
-               printf("virtual %s\n", (char *)commit->util);
-       else {
-               printf("%s ", find_unique_abbrev(commit->object.sha1, DEFAULT_ABBREV));
-               if (parse_commit(commit) != 0)
-                       printf("(bad commit)\n");
-               else {
-                       const char *s;
-                       int len;
-                       for (s = commit->buffer; *s; s++)
-                               if (*s == '\n' && s[1] == '\n') {
-                                       s += 2;
-                                       break;
-                               }
-                       for (len = 0; s[len] && '\n' != s[len]; len++)
-                               ; /* do nothing */
-                       printf("%.*s\n", len, s);
-               }
-       }
-}
-
-static int add_cacheinfo(unsigned int mode, const unsigned char *sha1,
-               const char *path, int stage, int refresh, int options)
-{
-       struct cache_entry *ce;
-       ce = make_cache_entry(mode, sha1 ? sha1 : null_sha1, path, stage, refresh);
-       if (!ce)
-               return error("addinfo_cache failed for path '%s'", path);
-       return add_cache_entry(ce, options);
-}
-
-/*
- * This is a global variable which is used in a number of places but
- * only written to in the 'merge' function.
- *
- * index_only == 1    => Don't leave any non-stage 0 entries in the cache and
- *                       don't update the working directory.
- *               0    => Leave unmerged entries in the cache and update
- *                       the working directory.
- */
-static int index_only = 0;
-
-static void init_tree_desc_from_tree(struct tree_desc *desc, struct tree *tree)
-{
-       parse_tree(tree);
-       init_tree_desc(desc, tree->buffer, tree->size);
-}
-
-static int git_merge_trees(int index_only,
-                          struct tree *common,
-                          struct tree *head,
-                          struct tree *merge)
-{
-       int rc;
-       struct tree_desc t[3];
-       struct unpack_trees_options opts;
-
-       memset(&opts, 0, sizeof(opts));
-       if (index_only)
-               opts.index_only = 1;
-       else
-               opts.update = 1;
-       opts.merge = 1;
-       opts.head_idx = 2;
-       opts.fn = threeway_merge;
-       opts.src_index = &the_index;
-       opts.dst_index = &the_index;
-
-       init_tree_desc_from_tree(t+0, common);
-       init_tree_desc_from_tree(t+1, head);
-       init_tree_desc_from_tree(t+2, merge);
-
-       rc = unpack_trees(3, t, &opts);
-       cache_tree_free(&active_cache_tree);
-       return rc;
-}
-
-struct tree *write_tree_from_memory(void)
-{
-       struct tree *result = NULL;
-
-       if (unmerged_cache()) {
-               int i;
-               output(0, "There are unmerged index entries:");
-               for (i = 0; i < active_nr; i++) {
-                       struct cache_entry *ce = active_cache[i];
-                       if (ce_stage(ce))
-                               output(0, "%d %.*s", ce_stage(ce), ce_namelen(ce), ce->name);
-               }
-               return NULL;
-       }
-
-       if (!active_cache_tree)
-               active_cache_tree = cache_tree();
-
-       if (!cache_tree_fully_valid(active_cache_tree) &&
-           cache_tree_update(active_cache_tree,
-                             active_cache, active_nr, 0, 0) < 0)
-               die("error building trees");
-
-       result = lookup_tree(active_cache_tree->sha1);
-
-       return result;
-}
-
-static int save_files_dirs(const unsigned char *sha1,
-               const char *base, int baselen, const char *path,
-               unsigned int mode, int stage, void *context)
-{
-       int len = strlen(path);
-       char *newpath = xmalloc(baselen + len + 1);
-       memcpy(newpath, base, baselen);
-       memcpy(newpath + baselen, path, len);
-       newpath[baselen + len] = '\0';
-
-       if (S_ISDIR(mode))
-               string_list_insert(newpath, &current_directory_set);
-       else
-               string_list_insert(newpath, &current_file_set);
-       free(newpath);
-
-       return READ_TREE_RECURSIVE;
-}
-
-static int get_files_dirs(struct tree *tree)
-{
-       int n;
-       if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, NULL))
-               return 0;
-       n = current_file_set.nr + current_directory_set.nr;
-       return n;
-}
-
-/*
- * Returns an index_entry instance which doesn't have to correspond to
- * a real cache entry in Git's index.
- */
-static struct stage_data *insert_stage_data(const char *path,
-               struct tree *o, struct tree *a, struct tree *b,
-               struct string_list *entries)
-{
-       struct string_list_item *item;
-       struct stage_data *e = xcalloc(1, sizeof(struct stage_data));
-       get_tree_entry(o->object.sha1, path,
-                       e->stages[1].sha, &e->stages[1].mode);
-       get_tree_entry(a->object.sha1, path,
-                       e->stages[2].sha, &e->stages[2].mode);
-       get_tree_entry(b->object.sha1, path,
-                       e->stages[3].sha, &e->stages[3].mode);
-       item = string_list_insert(path, entries);
-       item->util = e;
-       return e;
-}
-
-/*
- * Create a dictionary mapping file names to stage_data objects. The
- * dictionary contains one entry for every path with a non-zero stage entry.
- */
-static struct string_list *get_unmerged(void)
-{
-       struct string_list *unmerged = xcalloc(1, sizeof(struct string_list));
-       int i;
-
-       unmerged->strdup_strings = 1;
-
-       for (i = 0; i < active_nr; i++) {
-               struct string_list_item *item;
-               struct stage_data *e;
-               struct cache_entry *ce = active_cache[i];
-               if (!ce_stage(ce))
-                       continue;
-
-               item = string_list_lookup(ce->name, unmerged);
-               if (!item) {
-                       item = string_list_insert(ce->name, unmerged);
-                       item->util = xcalloc(1, sizeof(struct stage_data));
-               }
-               e = item->util;
-               e->stages[ce_stage(ce)].mode = ce->ce_mode;
-               hashcpy(e->stages[ce_stage(ce)].sha, ce->sha1);
-       }
-
-       return unmerged;
-}
-
-struct rename
-{
-       struct diff_filepair *pair;
-       struct stage_data *src_entry;
-       struct stage_data *dst_entry;
-       unsigned processed:1;
-};
-
-/*
- * Get information of all renames which occurred between 'o_tree' and
- * 'tree'. We need the three trees in the merge ('o_tree', 'a_tree' and
- * 'b_tree') to be able to associate the correct cache entries with
- * the rename information. 'tree' is always equal to either a_tree or b_tree.
- */
-static struct string_list *get_renames(struct tree *tree,
-                                       struct tree *o_tree,
-                                       struct tree *a_tree,
-                                       struct tree *b_tree,
-                                       struct string_list *entries)
-{
-       int i;
-       struct string_list *renames;
-       struct diff_options opts;
-
-       renames = xcalloc(1, sizeof(struct string_list));
-       diff_setup(&opts);
-       DIFF_OPT_SET(&opts, RECURSIVE);
-       opts.detect_rename = DIFF_DETECT_RENAME;
-       opts.rename_limit = merge_rename_limit >= 0 ? merge_rename_limit :
-                           diff_rename_limit >= 0 ? diff_rename_limit :
-                           500;
-       opts.warn_on_too_large_rename = 1;
-       opts.output_format = DIFF_FORMAT_NO_OUTPUT;
-       if (diff_setup_done(&opts) < 0)
-               die("diff setup failed");
-       diff_tree_sha1(o_tree->object.sha1, tree->object.sha1, "", &opts);
-       diffcore_std(&opts);
-       for (i = 0; i < diff_queued_diff.nr; ++i) {
-               struct string_list_item *item;
-               struct rename *re;
-               struct diff_filepair *pair = diff_queued_diff.queue[i];
-               if (pair->status != 'R') {
-                       diff_free_filepair(pair);
-                       continue;
-               }
-               re = xmalloc(sizeof(*re));
-               re->processed = 0;
-               re->pair = pair;
-               item = string_list_lookup(re->pair->one->path, entries);
-               if (!item)
-                       re->src_entry = insert_stage_data(re->pair->one->path,
-                                       o_tree, a_tree, b_tree, entries);
-               else
-                       re->src_entry = item->util;
-
-               item = string_list_lookup(re->pair->two->path, entries);
-               if (!item)
-                       re->dst_entry = insert_stage_data(re->pair->two->path,
-                                       o_tree, a_tree, b_tree, entries);
-               else
-                       re->dst_entry = item->util;
-               item = string_list_insert(pair->one->path, renames);
-               item->util = re;
-       }
-       opts.output_format = DIFF_FORMAT_NO_OUTPUT;
-       diff_queued_diff.nr = 0;
-       diff_flush(&opts);
-       return renames;
-}
-
-static int update_stages(const char *path, struct diff_filespec *o,
-                        struct diff_filespec *a, struct diff_filespec *b,
-                        int clear)
-{
-       int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE;
-       if (clear)
-               if (remove_file_from_cache(path))
-                       return -1;
-       if (o)
-               if (add_cacheinfo(o->mode, o->sha1, path, 1, 0, options))
-                       return -1;
-       if (a)
-               if (add_cacheinfo(a->mode, a->sha1, path, 2, 0, options))
-                       return -1;
-       if (b)
-               if (add_cacheinfo(b->mode, b->sha1, path, 3, 0, options))
-                       return -1;
-       return 0;
-}
-
-static int remove_file(int clean, const char *path, int no_wd)
-{
-       int update_cache = index_only || clean;
-       int update_working_directory = !index_only && !no_wd;
-
-       if (update_cache) {
-               if (remove_file_from_cache(path))
-                       return -1;
-       }
-       if (update_working_directory) {
-               if (remove_path(path))
-                       return -1;
-       }
-       return 0;
-}
-
-static char *unique_path(const char *path, const char *branch)
-{
-       char *newpath = xmalloc(strlen(path) + 1 + strlen(branch) + 8 + 1);
-       int suffix = 0;
-       struct stat st;
-       char *p = newpath + strlen(path);
-       strcpy(newpath, path);
-       *(p++) = '~';
-       strcpy(p, branch);
-       for (; *p; ++p)
-               if ('/' == *p)
-                       *p = '_';
-       while (string_list_has_string(&current_file_set, newpath) ||
-              string_list_has_string(&current_directory_set, newpath) ||
-              lstat(newpath, &st) == 0)
-               sprintf(p, "_%d", suffix++);
-
-       string_list_insert(newpath, &current_file_set);
-       return newpath;
-}
-
-static void flush_buffer(int fd, const char *buf, unsigned long size)
-{
-       while (size > 0) {
-               long ret = write_in_full(fd, buf, size);
-               if (ret < 0) {
-                       /* Ignore epipe */
-                       if (errno == EPIPE)
-                               break;
-                       die("merge-recursive: %s", strerror(errno));
-               } else if (!ret) {
-                       die("merge-recursive: disk full?");
-               }
-               size -= ret;
-               buf += ret;
-       }
-}
-
-static int make_room_for_path(const char *path)
-{
-       int status;
-       const char *msg = "failed to create path '%s'%s";
-
-       status = safe_create_leading_directories_const(path);
-       if (status) {
-               if (status == -3) {
-                       /* something else exists */
-                       error(msg, path, ": perhaps a D/F conflict?");
-                       return -1;
-               }
-               die(msg, path, "");
-       }
-
-       /* Successful unlink is good.. */
-       if (!unlink(path))
-               return 0;
-       /* .. and so is no existing file */
-       if (errno == ENOENT)
-               return 0;
-       /* .. but not some other error (who really cares what?) */
-       return error(msg, path, ": perhaps a D/F conflict?");
-}
-
-static void update_file_flags(const unsigned char *sha,
-                             unsigned mode,
-                             const char *path,
-                             int update_cache,
-                             int update_wd)
-{
-       if (index_only)
-               update_wd = 0;
-
-       if (update_wd) {
-               enum object_type type;
-               void *buf;
-               unsigned long size;
-
-               if (S_ISGITLINK(mode))
-                       die("cannot read object %s '%s': It is a submodule!",
-                           sha1_to_hex(sha), path);
-
-               buf = read_sha1_file(sha, &type, &size);
-               if (!buf)
-                       die("cannot read object %s '%s'", sha1_to_hex(sha), path);
-               if (type != OBJ_BLOB)
-                       die("blob expected for %s '%s'", sha1_to_hex(sha), path);
-               if (S_ISREG(mode)) {
-                       struct strbuf strbuf;
-                       strbuf_init(&strbuf, 0);
-                       if (convert_to_working_tree(path, buf, size, &strbuf)) {
-                               free(buf);
-                               size = strbuf.len;
-                               buf = strbuf_detach(&strbuf, NULL);
-                       }
-               }
-
-               if (make_room_for_path(path) < 0) {
-                       update_wd = 0;
-                       free(buf);
-                       goto update_index;
-               }
-               if (S_ISREG(mode) || (!has_symlinks && S_ISLNK(mode))) {
-                       int fd;
-                       if (mode & 0100)
-                               mode = 0777;
-                       else
-                               mode = 0666;
-                       fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
-                       if (fd < 0)
-                               die("failed to open %s: %s", path, strerror(errno));
-                       flush_buffer(fd, buf, size);
-                       close(fd);
-               } else if (S_ISLNK(mode)) {
-                       char *lnk = xmemdupz(buf, size);
-                       safe_create_leading_directories_const(path);
-                       unlink(path);
-                       symlink(lnk, path);
-                       free(lnk);
-               } else
-                       die("do not know what to do with %06o %s '%s'",
-                           mode, sha1_to_hex(sha), path);
-               free(buf);
-       }
- update_index:
-       if (update_cache)
-               add_cacheinfo(mode, sha, path, 0, update_wd, ADD_CACHE_OK_TO_ADD);
-}
-
-static void update_file(int clean,
-                       const unsigned char *sha,
-                       unsigned mode,
-                       const char *path)
-{
-       update_file_flags(sha, mode, path, index_only || clean, !index_only);
-}
-
-/* Low level file merging, update and removal */
-
-struct merge_file_info
-{
-       unsigned char sha[20];
-       unsigned mode;
-       unsigned clean:1,
-                merge:1;
-};
-
-static void fill_mm(const unsigned char *sha1, mmfile_t *mm)
-{
-       unsigned long size;
-       enum object_type type;
-
-       if (!hashcmp(sha1, null_sha1)) {
-               mm->ptr = xstrdup("");
-               mm->size = 0;
-               return;
-       }
-
-       mm->ptr = read_sha1_file(sha1, &type, &size);
-       if (!mm->ptr || type != OBJ_BLOB)
-               die("unable to read blob object %s", sha1_to_hex(sha1));
-       mm->size = size;
-}
-
-static int merge_3way(mmbuffer_t *result_buf,
-                     struct diff_filespec *o,
-                     struct diff_filespec *a,
-                     struct diff_filespec *b,
-                     const char *branch1,
-                     const char *branch2)
-{
-       mmfile_t orig, src1, src2;
-       char *name1, *name2;
-       int merge_status;
-
-       name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
-       name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
-
-       fill_mm(o->sha1, &orig);
-       fill_mm(a->sha1, &src1);
-       fill_mm(b->sha1, &src2);
-
-       merge_status = ll_merge(result_buf, a->path, &orig,
-                               &src1, name1, &src2, name2,
-                               index_only);
-
-       free(name1);
-       free(name2);
-       free(orig.ptr);
-       free(src1.ptr);
-       free(src2.ptr);
-       return merge_status;
-}
-
-static struct merge_file_info merge_file(struct diff_filespec *o,
-               struct diff_filespec *a, struct diff_filespec *b,
-               const char *branch1, const char *branch2)
-{
-       struct merge_file_info result;
-       result.merge = 0;
-       result.clean = 1;
-
-       if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
-               result.clean = 0;
-               if (S_ISREG(a->mode)) {
-                       result.mode = a->mode;
-                       hashcpy(result.sha, a->sha1);
-               } else {
-                       result.mode = b->mode;
-                       hashcpy(result.sha, b->sha1);
-               }
-       } else {
-               if (!sha_eq(a->sha1, o->sha1) && !sha_eq(b->sha1, o->sha1))
-                       result.merge = 1;
-
-               /*
-                * Merge modes
-                */
-               if (a->mode == b->mode || a->mode == o->mode)
-                       result.mode = b->mode;
-               else {
-                       result.mode = a->mode;
-                       if (b->mode != o->mode) {
-                               result.clean = 0;
-                               result.merge = 1;
-                       }
-               }
-
-               if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, o->sha1))
-                       hashcpy(result.sha, b->sha1);
-               else if (sha_eq(b->sha1, o->sha1))
-                       hashcpy(result.sha, a->sha1);
-               else if (S_ISREG(a->mode)) {
-                       mmbuffer_t result_buf;
-                       int merge_status;
-
-                       merge_status = merge_3way(&result_buf, o, a, b,
-                                                 branch1, branch2);
-
-                       if ((merge_status < 0) || !result_buf.ptr)
-                               die("Failed to execute internal merge");
-
-                       if (write_sha1_file(result_buf.ptr, result_buf.size,
-                                           blob_type, result.sha))
-                               die("Unable to add %s to database",
-                                   a->path);
-
-                       free(result_buf.ptr);
-                       result.clean = (merge_status == 0);
-               } else if (S_ISGITLINK(a->mode)) {
-                       result.clean = 0;
-                       hashcpy(result.sha, a->sha1);
-               } else if (S_ISLNK(a->mode)) {
-                       hashcpy(result.sha, a->sha1);
-
-                       if (!sha_eq(a->sha1, b->sha1))
-                               result.clean = 0;
-               } else {
-                       die("unsupported object type in the tree");
-               }
-       }
-
-       return result;
-}
-
-static void conflict_rename_rename(struct rename *ren1,
-                                  const char *branch1,
-                                  struct rename *ren2,
-                                  const char *branch2)
-{
-       char *del[2];
-       int delp = 0;
-       const char *ren1_dst = ren1->pair->two->path;
-       const char *ren2_dst = ren2->pair->two->path;
-       const char *dst_name1 = ren1_dst;
-       const char *dst_name2 = ren2_dst;
-       if (string_list_has_string(&current_directory_set, ren1_dst)) {
-               dst_name1 = del[delp++] = unique_path(ren1_dst, branch1);
-               output(1, "%s is a directory in %s added as %s instead",
-                      ren1_dst, branch2, dst_name1);
-               remove_file(0, ren1_dst, 0);
-       }
-       if (string_list_has_string(&current_directory_set, ren2_dst)) {
-               dst_name2 = del[delp++] = unique_path(ren2_dst, branch2);
-               output(1, "%s is a directory in %s added as %s instead",
-                      ren2_dst, branch1, dst_name2);
-               remove_file(0, ren2_dst, 0);
-       }
-       if (index_only) {
-               remove_file_from_cache(dst_name1);
-               remove_file_from_cache(dst_name2);
-               /*
-                * Uncomment to leave the conflicting names in the resulting tree
-                *
-                * update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
-                * update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, dst_name2);
-                */
-       } else {
-               update_stages(dst_name1, NULL, ren1->pair->two, NULL, 1);
-               update_stages(dst_name2, NULL, NULL, ren2->pair->two, 1);
-       }
-       while (delp--)
-               free(del[delp]);
-}
-
-static void conflict_rename_dir(struct rename *ren1,
-                               const char *branch1)
-{
-       char *new_path = unique_path(ren1->pair->two->path, branch1);
-       output(1, "Renamed %s to %s instead", ren1->pair->one->path, new_path);
-       remove_file(0, ren1->pair->two->path, 0);
-       update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
-       free(new_path);
-}
-
-static void conflict_rename_rename_2(struct rename *ren1,
-                                    const char *branch1,
-                                    struct rename *ren2,
-                                    const char *branch2)
-{
-       char *new_path1 = unique_path(ren1->pair->two->path, branch1);
-       char *new_path2 = unique_path(ren2->pair->two->path, branch2);
-       output(1, "Renamed %s to %s and %s to %s instead",
-              ren1->pair->one->path, new_path1,
-              ren2->pair->one->path, new_path2);
-       remove_file(0, ren1->pair->two->path, 0);
-       update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
-       update_file(0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
-       free(new_path2);
-       free(new_path1);
-}
-
-static int process_renames(struct string_list *a_renames,
-                          struct string_list *b_renames,
-                          const char *a_branch,
-                          const char *b_branch)
-{
-       int clean_merge = 1, i, j;
-       struct string_list a_by_dst = {NULL, 0, 0, 0}, b_by_dst = {NULL, 0, 0, 0};
-       const struct rename *sre;
-
-       for (i = 0; i < a_renames->nr; i++) {
-               sre = a_renames->items[i].util;
-               string_list_insert(sre->pair->two->path, &a_by_dst)->util
-                       = sre->dst_entry;
-       }
-       for (i = 0; i < b_renames->nr; i++) {
-               sre = b_renames->items[i].util;
-               string_list_insert(sre->pair->two->path, &b_by_dst)->util
-                       = sre->dst_entry;
-       }
-
-       for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
-               int compare;
-               char *src;
-               struct string_list *renames1, *renames2, *renames2Dst;
-               struct rename *ren1 = NULL, *ren2 = NULL;
-               const char *branch1, *branch2;
-               const char *ren1_src, *ren1_dst;
-
-               if (i >= a_renames->nr) {
-                       compare = 1;
-                       ren2 = b_renames->items[j++].util;
-               } else if (j >= b_renames->nr) {
-                       compare = -1;
-                       ren1 = a_renames->items[i++].util;
-               } else {
-                       compare = strcmp(a_renames->items[i].string,
-                                       b_renames->items[j].string);
-                       if (compare <= 0)
-                               ren1 = a_renames->items[i++].util;
-                       if (compare >= 0)
-                               ren2 = b_renames->items[j++].util;
-               }
-
-               /* TODO: refactor, so that 1/2 are not needed */
-               if (ren1) {
-                       renames1 = a_renames;
-                       renames2 = b_renames;
-                       renames2Dst = &b_by_dst;
-                       branch1 = a_branch;
-                       branch2 = b_branch;
-               } else {
-                       struct rename *tmp;
-                       renames1 = b_renames;
-                       renames2 = a_renames;
-                       renames2Dst = &a_by_dst;
-                       branch1 = b_branch;
-                       branch2 = a_branch;
-                       tmp = ren2;
-                       ren2 = ren1;
-                       ren1 = tmp;
-               }
-               src = ren1->pair->one->path;
-
-               ren1->dst_entry->processed = 1;
-               ren1->src_entry->processed = 1;
-
-               if (ren1->processed)
-                       continue;
-               ren1->processed = 1;
-
-               ren1_src = ren1->pair->one->path;
-               ren1_dst = ren1->pair->two->path;
-
-               if (ren2) {
-                       const char *ren2_src = ren2->pair->one->path;
-                       const char *ren2_dst = ren2->pair->two->path;
-                       /* Renamed in 1 and renamed in 2 */
-                       if (strcmp(ren1_src, ren2_src) != 0)
-                               die("ren1.src != ren2.src");
-                       ren2->dst_entry->processed = 1;
-                       ren2->processed = 1;
-                       if (strcmp(ren1_dst, ren2_dst) != 0) {
-                               clean_merge = 0;
-                               output(1, "CONFLICT (rename/rename): "
-                                      "Rename \"%s\"->\"%s\" in branch \"%s\" "
-                                      "rename \"%s\"->\"%s\" in \"%s\"%s",
-                                      src, ren1_dst, branch1,
-                                      src, ren2_dst, branch2,
-                                      index_only ? " (left unresolved)": "");
-                               if (index_only) {
-                                       remove_file_from_cache(src);
-                                       update_file(0, ren1->pair->one->sha1,
-                                                   ren1->pair->one->mode, src);
-                               }
-                               conflict_rename_rename(ren1, branch1, ren2, branch2);
-                       } else {
-                               struct merge_file_info mfi;
-                               remove_file(1, ren1_src, 1);
-                               mfi = merge_file(ren1->pair->one,
-                                                ren1->pair->two,
-                                                ren2->pair->two,
-                                                branch1,
-                                                branch2);
-                               if (mfi.merge || !mfi.clean)
-                                       output(1, "Renamed %s->%s", src, ren1_dst);
-
-                               if (mfi.merge)
-                                       output(2, "Auto-merged %s", ren1_dst);
-
-                               if (!mfi.clean) {
-                                       output(1, "CONFLICT (content): merge conflict in %s",
-                                              ren1_dst);
-                                       clean_merge = 0;
-
-                                       if (!index_only)
-                                               update_stages(ren1_dst,
-                                                             ren1->pair->one,
-                                                             ren1->pair->two,
-                                                             ren2->pair->two,
-                                                             1 /* clear */);
-                               }
-                               update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
-                       }
-               } else {
-                       /* Renamed in 1, maybe changed in 2 */
-                       struct string_list_item *item;
-                       /* we only use sha1 and mode of these */
-                       struct diff_filespec src_other, dst_other;
-                       int try_merge, stage = a_renames == renames1 ? 3: 2;
-
-                       remove_file(1, ren1_src, index_only || stage == 3);
-
-                       hashcpy(src_other.sha1, ren1->src_entry->stages[stage].sha);
-                       src_other.mode = ren1->src_entry->stages[stage].mode;
-                       hashcpy(dst_other.sha1, ren1->dst_entry->stages[stage].sha);
-                       dst_other.mode = ren1->dst_entry->stages[stage].mode;
-
-                       try_merge = 0;
-
-                       if (string_list_has_string(&current_directory_set, ren1_dst)) {
-                               clean_merge = 0;
-                               output(1, "CONFLICT (rename/directory): Renamed %s->%s in %s "
-                                      " directory %s added in %s",
-                                      ren1_src, ren1_dst, branch1,
-                                      ren1_dst, branch2);
-                               conflict_rename_dir(ren1, branch1);
-                       } else if (sha_eq(src_other.sha1, null_sha1)) {
-                               clean_merge = 0;
-                               output(1, "CONFLICT (rename/delete): Renamed %s->%s in %s "
-                                      "and deleted in %s",
-                                      ren1_src, ren1_dst, branch1,
-                                      branch2);
-                               update_file(0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
-                       } else if (!sha_eq(dst_other.sha1, null_sha1)) {
-                               const char *new_path;
-                               clean_merge = 0;
-                               try_merge = 1;
-                               output(1, "CONFLICT (rename/add): Renamed %s->%s in %s. "
-                                      "%s added in %s",
-                                      ren1_src, ren1_dst, branch1,
-                                      ren1_dst, branch2);
-                               new_path = unique_path(ren1_dst, branch2);
-                               output(1, "Added as %s instead", new_path);
-                               update_file(0, dst_other.sha1, dst_other.mode, new_path);
-                       } else if ((item = string_list_lookup(ren1_dst, renames2Dst))) {
-                               ren2 = item->util;
-                               clean_merge = 0;
-                               ren2->processed = 1;
-                               output(1, "CONFLICT (rename/rename): Renamed %s->%s in %s. "
-                                      "Renamed %s->%s in %s",
-                                      ren1_src, ren1_dst, branch1,
-                                      ren2->pair->one->path, ren2->pair->two->path, branch2);
-                               conflict_rename_rename_2(ren1, branch1, ren2, branch2);
-                       } else
-                               try_merge = 1;
-
-                       if (try_merge) {
-                               struct diff_filespec *o, *a, *b;
-                               struct merge_file_info mfi;
-                               src_other.path = (char *)ren1_src;
-
-                               o = ren1->pair->one;
-                               if (a_renames == renames1) {
-                                       a = ren1->pair->two;
-                                       b = &src_other;
-                               } else {
-                                       b = ren1->pair->two;
-                                       a = &src_other;
-                               }
-                               mfi = merge_file(o, a, b,
-                                               a_branch, b_branch);
-
-                               if (mfi.clean &&
-                                   sha_eq(mfi.sha, ren1->pair->two->sha1) &&
-                                   mfi.mode == ren1->pair->two->mode)
-                                       /*
-                                        * This messaged is part of
-                                        * t6022 test. If you change
-                                        * it update the test too.
-                                        */
-                                       output(3, "Skipped %s (merged same as existing)", ren1_dst);
-                               else {
-                                       if (mfi.merge || !mfi.clean)
-                                               output(1, "Renamed %s => %s", ren1_src, ren1_dst);
-                                       if (mfi.merge)
-                                               output(2, "Auto-merged %s", ren1_dst);
-                                       if (!mfi.clean) {
-                                               output(1, "CONFLICT (rename/modify): Merge conflict in %s",
-                                                      ren1_dst);
-                                               clean_merge = 0;
-
-                                               if (!index_only)
-                                                       update_stages(ren1_dst,
-                                                                     o, a, b, 1);
-                                       }
-                                       update_file(mfi.clean, mfi.sha, mfi.mode, ren1_dst);
-                               }
-                       }
-               }
-       }
-       string_list_clear(&a_by_dst, 0);
-       string_list_clear(&b_by_dst, 0);
-
-       return clean_merge;
-}
-
-static unsigned char *stage_sha(const unsigned char *sha, unsigned mode)
-{
-       return (is_null_sha1(sha) || mode == 0) ? NULL: (unsigned char *)sha;
-}
-
-/* Per entry merge function */
-static int process_entry(const char *path, struct stage_data *entry,
-                        const char *branch1,
-                        const char *branch2)
-{
-       /*
-       printf("processing entry, clean cache: %s\n", index_only ? "yes": "no");
-       print_index_entry("\tpath: ", entry);
-       */
-       int clean_merge = 1;
-       unsigned o_mode = entry->stages[1].mode;
-       unsigned a_mode = entry->stages[2].mode;
-       unsigned b_mode = entry->stages[3].mode;
-       unsigned char *o_sha = stage_sha(entry->stages[1].sha, o_mode);
-       unsigned char *a_sha = stage_sha(entry->stages[2].sha, a_mode);
-       unsigned char *b_sha = stage_sha(entry->stages[3].sha, b_mode);
-
-       if (o_sha && (!a_sha || !b_sha)) {
-               /* Case A: Deleted in one */
-               if ((!a_sha && !b_sha) ||
-                   (sha_eq(a_sha, o_sha) && !b_sha) ||
-                   (!a_sha && sha_eq(b_sha, o_sha))) {
-                       /* Deleted in both or deleted in one and
-                        * unchanged in the other */
-                       if (a_sha)
-                               output(2, "Removed %s", path);
-                       /* do not touch working file if it did not exist */
-                       remove_file(1, path, !a_sha);
-               } else {
-                       /* Deleted in one and changed in the other */
-                       clean_merge = 0;
-                       if (!a_sha) {
-                               output(1, "CONFLICT (delete/modify): %s deleted in %s "
-                                      "and modified in %s. Version %s of %s left in tree.",
-                                      path, branch1,
-                                      branch2, branch2, path);
-                               update_file(0, b_sha, b_mode, path);
-                       } else {
-                               output(1, "CONFLICT (delete/modify): %s deleted in %s "
-                                      "and modified in %s. Version %s of %s left in tree.",
-                                      path, branch2,
-                                      branch1, branch1, path);
-                               update_file(0, a_sha, a_mode, path);
-                       }
-               }
-
-       } else if ((!o_sha && a_sha && !b_sha) ||
-                  (!o_sha && !a_sha && b_sha)) {
-               /* Case B: Added in one. */
-               const char *add_branch;
-               const char *other_branch;
-               unsigned mode;
-               const unsigned char *sha;
-               const char *conf;
-
-               if (a_sha) {
-                       add_branch = branch1;
-                       other_branch = branch2;
-                       mode = a_mode;
-                       sha = a_sha;
-                       conf = "file/directory";
-               } else {
-                       add_branch = branch2;
-                       other_branch = branch1;
-                       mode = b_mode;
-                       sha = b_sha;
-                       conf = "directory/file";
-               }
-               if (string_list_has_string(&current_directory_set, path)) {
-                       const char *new_path = unique_path(path, add_branch);
-                       clean_merge = 0;
-                       output(1, "CONFLICT (%s): There is a directory with name %s in %s. "
-                              "Added %s as %s",
-                              conf, path, other_branch, path, new_path);
-                       remove_file(0, path, 0);
-                       update_file(0, sha, mode, new_path);
-               } else {
-                       output(2, "Added %s", path);
-                       update_file(1, sha, mode, path);
-               }
-       } else if (a_sha && b_sha) {
-               /* Case C: Added in both (check for same permissions) and */
-               /* case D: Modified in both, but differently. */
-               const char *reason = "content";
-               struct merge_file_info mfi;
-               struct diff_filespec o, a, b;
-
-               if (!o_sha) {
-                       reason = "add/add";
-                       o_sha = (unsigned char *)null_sha1;
-               }
-               output(2, "Auto-merged %s", path);
-               o.path = a.path = b.path = (char *)path;
-               hashcpy(o.sha1, o_sha);
-               o.mode = o_mode;
-               hashcpy(a.sha1, a_sha);
-               a.mode = a_mode;
-               hashcpy(b.sha1, b_sha);
-               b.mode = b_mode;
-
-               mfi = merge_file(&o, &a, &b,
-                                branch1, branch2);
-
-               clean_merge = mfi.clean;
-               if (mfi.clean)
-                       update_file(1, mfi.sha, mfi.mode, path);
-               else if (S_ISGITLINK(mfi.mode))
-                       output(1, "CONFLICT (submodule): Merge conflict in %s "
-                              "- needs %s", path, sha1_to_hex(b.sha1));
-               else {
-                       output(1, "CONFLICT (%s): Merge conflict in %s",
-                                       reason, path);
-
-                       if (index_only)
-                               update_file(0, mfi.sha, mfi.mode, path);
-                       else
-                               update_file_flags(mfi.sha, mfi.mode, path,
-                                             0 /* update_cache */, 1 /* update_working_directory */);
-               }
-       } else if (!o_sha && !a_sha && !b_sha) {
-               /*
-                * this entry was deleted altogether. a_mode == 0 means
-                * we had that path and want to actively remove it.
-                */
-               remove_file(1, path, !a_mode);
-       } else
-               die("Fatal merge failure, shouldn't happen.");
-
-       return clean_merge;
-}
-
-int merge_trees(struct tree *head,
-               struct tree *merge,
-               struct tree *common,
-               const char *branch1,
-               const char *branch2,
-               struct tree **result)
-{
-       int code, clean;
-
-       if (subtree_merge) {
-               merge = shift_tree_object(head, merge);
-               common = shift_tree_object(head, common);
-       }
-
-       if (sha_eq(common->object.sha1, merge->object.sha1)) {
-               output(0, "Already uptodate!");
-               *result = head;
-               return 1;
-       }
-
-       code = git_merge_trees(index_only, common, head, merge);
-
-       if (code != 0)
-               die("merging of trees %s and %s failed",
-                   sha1_to_hex(head->object.sha1),
-                   sha1_to_hex(merge->object.sha1));
-
-       if (unmerged_cache()) {
-               struct string_list *entries, *re_head, *re_merge;
-               int i;
-               string_list_clear(&current_file_set, 1);
-               string_list_clear(&current_directory_set, 1);
-               get_files_dirs(head);
-               get_files_dirs(merge);
-
-               entries = get_unmerged();
-               re_head  = get_renames(head, common, head, merge, entries);
-               re_merge = get_renames(merge, common, head, merge, entries);
-               clean = process_renames(re_head, re_merge,
-                               branch1, branch2);
-               for (i = 0; i < entries->nr; i++) {
-                       const char *path = entries->items[i].string;
-                       struct stage_data *e = entries->items[i].util;
-                       if (!e->processed
-                               && !process_entry(path, e, branch1, branch2))
-                               clean = 0;
-               }
-
-               string_list_clear(re_merge, 0);
-               string_list_clear(re_head, 0);
-               string_list_clear(entries, 1);
-
-       }
-       else
-               clean = 1;
-
-       if (index_only)
-               *result = write_tree_from_memory();
-
-       return clean;
-}
-
-static struct commit_list *reverse_commit_list(struct commit_list *list)
-{
-       struct commit_list *next = NULL, *current, *backup;
-       for (current = list; current; current = backup) {
-               backup = current->next;
-               current->next = next;
-               next = current;
-       }
-       return next;
-}
-
-/*
- * Merge the commits h1 and h2, return the resulting virtual
- * commit object and a flag indicating the cleanness of the merge.
- */
-int merge_recursive(struct commit *h1,
-                   struct commit *h2,
-                   const char *branch1,
-                   const char *branch2,
-                   struct commit_list *ca,
-                   struct commit **result)
-{
-       struct commit_list *iter;
-       struct commit *merged_common_ancestors;
-       struct tree *mrtree = mrtree;
-       int clean;
-
-       if (show(4)) {
-               output(4, "Merging:");
-               output_commit_title(h1);
-               output_commit_title(h2);
-       }
-
-       if (!ca) {
-               ca = get_merge_bases(h1, h2, 1);
-               ca = reverse_commit_list(ca);
-       }
-
-       if (show(5)) {
-               output(5, "found %u common ancestor(s):", commit_list_count(ca));
-               for (iter = ca; iter; iter = iter->next)
-                       output_commit_title(iter->item);
-       }
-
-       merged_common_ancestors = pop_commit(&ca);
-       if (merged_common_ancestors == NULL) {
-               /* if there is no common ancestor, make an empty tree */
-               struct tree *tree = xcalloc(1, sizeof(struct tree));
-
-               tree->object.parsed = 1;
-               tree->object.type = OBJ_TREE;
-               pretend_sha1_file(NULL, 0, OBJ_TREE, tree->object.sha1);
-               merged_common_ancestors = make_virtual_commit(tree, "ancestor");
-       }
-
-       for (iter = ca; iter; iter = iter->next) {
-               call_depth++;
-               /*
-                * When the merge fails, the result contains files
-                * with conflict markers. The cleanness flag is
-                * ignored, it was never actually used, as result of
-                * merge_trees has always overwritten it: the committed
-                * "conflicts" were already resolved.
-                */
-               discard_cache();
-               merge_recursive(merged_common_ancestors, iter->item,
-                               "Temporary merge branch 1",
-                               "Temporary merge branch 2",
-                               NULL,
-                               &merged_common_ancestors);
-               call_depth--;
-
-               if (!merged_common_ancestors)
-                       die("merge returned no commit");
-       }
-
-       discard_cache();
-       if (!call_depth) {
-               read_cache();
-               index_only = 0;
-       } else
-               index_only = 1;
-
-       clean = merge_trees(h1->tree, h2->tree, merged_common_ancestors->tree,
-                           branch1, branch2, &mrtree);
-
-       if (index_only) {
-               *result = make_virtual_commit(mrtree, "merged tree");
-               commit_list_insert(h1, &(*result)->parents);
-               commit_list_insert(h2, &(*result)->parents->next);
-       }
-       flush_output();
-       return clean;
-}
-
 static const char *better_branch_name(const char *branch)
 {
        static char githead_env[8 + 40 + 1];
@@ -1295,103 +15,70 @@ static const char *better_branch_name(const char *branch)
        return name ? name : branch;
 }
 
-static struct commit *get_ref(const char *ref)
-{
-       unsigned char sha1[20];
-       struct object *object;
-
-       if (get_sha1(ref, sha1))
-               die("Could not resolve ref '%s'", ref);
-       object = deref_tag(parse_object(sha1), ref, strlen(ref));
-       if (!object)
-               return NULL;
-       if (object->type == OBJ_TREE)
-               return make_virtual_commit((struct tree*)object,
-                       better_branch_name(ref));
-       if (object->type != OBJ_COMMIT)
-               return NULL;
-       if (parse_commit((struct commit *)object))
-               die("Could not parse commit '%s'", sha1_to_hex(object->sha1));
-       return (struct commit *)object;
-}
-
-static int merge_config(const char *var, const char *value, void *cb)
-{
-       if (!strcasecmp(var, "merge.verbosity")) {
-               verbosity = git_config_int(var, value);
-               return 0;
-       }
-       if (!strcasecmp(var, "diff.renamelimit")) {
-               diff_rename_limit = git_config_int(var, value);
-               return 0;
-       }
-       if (!strcasecmp(var, "merge.renamelimit")) {
-               merge_rename_limit = git_config_int(var, value);
-               return 0;
-       }
-       return git_default_config(var, value, cb);
-}
-
 int cmd_merge_recursive(int argc, const char **argv, const char *prefix)
 {
-       static const char *bases[20];
-       static unsigned bases_count = 0;
-       int i, clean;
-       const char *branch1, *branch2;
-       struct commit *result, *h1, *h2;
-       struct commit_list *ca = NULL;
-       struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
-       int index_fd;
+       const unsigned char *bases[21];
+       unsigned bases_count = 0;
+       int i, failed;
+       unsigned char h1[20], h2[20];
+       struct merge_options o;
+       struct commit *result;
 
-       if (argv[0]) {
-               int namelen = strlen(argv[0]);
-               if (8 < namelen &&
-                   !strcmp(argv[0] + namelen - 8, "-subtree"))
-                       subtree_merge = 1;
-       }
-
-       git_config(merge_config, NULL);
-       if (getenv("GIT_MERGE_VERBOSITY"))
-               verbosity = strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
+       init_merge_options(&o);
+       if (argv[0] && !suffixcmp(argv[0], "-subtree"))
+               o.subtree_shift = "";
 
        if (argc < 4)
-               die("Usage: %s <base>... -- <head> <remote> ...\n", argv[0]);
+               usagef("%s <base>... -- <head> <remote> ...", argv[0]);
 
        for (i = 1; i < argc; ++i) {
-               if (!strcmp(argv[i], "--"))
-                       break;
-               if (bases_count < sizeof(bases)/sizeof(*bases))
-                       bases[bases_count++] = argv[i];
+               const char *arg = argv[i];
+
+               if (!prefixcmp(arg, "--")) {
+                       if (!arg[2])
+                               break;
+                       if (!strcmp(arg+2, "ours"))
+                               o.recursive_variant = MERGE_RECURSIVE_OURS;
+                       else if (!strcmp(arg+2, "theirs"))
+                               o.recursive_variant = MERGE_RECURSIVE_THEIRS;
+                       else if (!strcmp(arg+2, "subtree"))
+                               o.subtree_shift = "";
+                       else if (!prefixcmp(arg+2, "subtree="))
+                               o.subtree_shift = arg + 10;
+                       else
+                               die("Unknown option %s", arg);
+                       continue;
+               }
+               if (bases_count < ARRAY_SIZE(bases)-1) {
+                       unsigned char *sha = xmalloc(20);
+                       if (get_sha1(argv[i], sha))
+                               die("Could not parse object '%s'", argv[i]);
+                       bases[bases_count++] = sha;
+               }
+               else
+                       warning("Cannot handle more than %d bases. "
+                               "Ignoring %s.",
+                               (int)ARRAY_SIZE(bases)-1, argv[i]);
        }
        if (argc - i != 3) /* "--" "<head>" "<remote>" */
                die("Not handling anything other than two heads merge.");
-       if (verbosity >= 5)
-               buffer_output = 0;
 
-       branch1 = argv[++i];
-       branch2 = argv[++i];
+       o.branch1 = argv[++i];
+       o.branch2 = argv[++i];
 
-       h1 = get_ref(branch1);
-       h2 = get_ref(branch2);
+       if (get_sha1(o.branch1, h1))
+               die("Could not resolve ref '%s'", o.branch1);
+       if (get_sha1(o.branch2, h2))
+               die("Could not resolve ref '%s'", o.branch2);
 
-       branch1 = better_branch_name(branch1);
-       branch2 = better_branch_name(branch2);
-
-       if (show(3))
-               printf("Merging %s with %s\n", branch1, branch2);
-
-       index_fd = hold_locked_index(lock, 1);
-
-       for (i = 0; i < bases_count; i++) {
-               struct commit *ancestor = get_ref(bases[i]);
-               ca = commit_list_insert(ancestor, &ca);
-       }
-       clean = merge_recursive(h1, h2, branch1, branch2, ca, &result);
+       o.branch1 = better_branch_name(o.branch1);
+       o.branch2 = better_branch_name(o.branch2);
 
-       if (active_cache_changed &&
-           (write_cache(index_fd, active_cache, active_nr) ||
-            commit_locked_index(lock)))
-                       die ("unable to write %s", get_index_file());
+       if (o.verbosity >= 3)
+               printf("Merging %s with %s\n", o.branch1, o.branch2);
 
-       return clean ? 0: 1;
+       failed = merge_recursive_generic(&o, h1, h2, bases_count, bases, &result);
+       if (failed < 0)
+               return 128; /* die() error code */
+       return failed;
 }