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-rw-r--r--merge-recursive.c1393
1 files changed, 1393 insertions, 0 deletions
diff --git a/merge-recursive.c b/merge-recursive.c
new file mode 100644
index 0000000..b97026b
--- /dev/null
+++ b/merge-recursive.c
@@ -0,0 +1,1393 @@
+/*
+ * 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 "attr.h"
+#include "merge-recursive.h"
+#include "dir.h"
+
+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.
+ */
+
+struct commit *make_virtual_commit(struct tree *tree, const char *comment)
+{
+ struct commit *commit = xcalloc(1, sizeof(struct commit));
+ commit->tree = tree;
+ commit->util = (void*)comment;
+ /* 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 int show(struct merge_options *o, int v)
+{
+ return (!o->call_depth && o->verbosity >= v) || o->verbosity >= 5;
+}
+
+static void flush_output(struct merge_options *o)
+{
+ if (o->obuf.len) {
+ fputs(o->obuf.buf, stdout);
+ strbuf_reset(&o->obuf);
+ }
+}
+
+static void output(struct merge_options *o, int v, const char *fmt, ...)
+{
+ int len;
+ va_list ap;
+
+ if (!show(o, v))
+ return;
+
+ strbuf_grow(&o->obuf, o->call_depth * 2 + 2);
+ memset(o->obuf.buf + o->obuf.len, ' ', o->call_depth * 2);
+ strbuf_setlen(&o->obuf, o->obuf.len + o->call_depth * 2);
+
+ va_start(ap, fmt);
+ len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
+ va_end(ap);
+
+ if (len < 0)
+ len = 0;
+ if (len >= strbuf_avail(&o->obuf)) {
+ strbuf_grow(&o->obuf, len + 2);
+ va_start(ap, fmt);
+ len = vsnprintf(o->obuf.buf + o->obuf.len, strbuf_avail(&o->obuf), fmt, ap);
+ va_end(ap);
+ if (len >= strbuf_avail(&o->obuf)) {
+ die("this should not happen, your snprintf is broken");
+ }
+ }
+ strbuf_setlen(&o->obuf, o->obuf.len + len);
+ strbuf_add(&o->obuf, "\n", 1);
+ if (!o->buffer_output)
+ flush_output(o);
+}
+
+static void output_commit_title(struct merge_options *o, struct commit *commit)
+{
+ int i;
+ flush_output(o);
+ for (i = o->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);
+}
+
+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(struct merge_options *o)
+{
+ struct tree *result = NULL;
+
+ if (unmerged_cache()) {
+ int i;
+ output(o, 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(o, 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);
+ struct merge_options *o = context;
+
+ memcpy(newpath, base, baselen);
+ memcpy(newpath + baselen, path, len);
+ newpath[baselen + len] = '\0';
+
+ if (S_ISDIR(mode))
+ string_list_insert(newpath, &o->current_directory_set);
+ else
+ string_list_insert(newpath, &o->current_file_set);
+ free(newpath);
+
+ return READ_TREE_RECURSIVE;
+}
+
+static int get_files_dirs(struct merge_options *o, struct tree *tree)
+{
+ int n;
+ if (read_tree_recursive(tree, "", 0, 0, NULL, save_files_dirs, o))
+ return 0;
+ n = o->current_file_set.nr + o->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 merge_options *o,
+ 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 = o->merge_rename_limit >= 0 ? o->merge_rename_limit :
+ o->diff_rename_limit >= 0 ? o->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(struct merge_options *o, int clean,
+ const char *path, int no_wd)
+{
+ int update_cache = o->call_depth || clean;
+ int update_working_directory = !o->call_depth && !no_wd;
+
+ if (update_cache) {
+ if (remove_file_from_cache(path))
+ return -1;
+ }
+ if (update_working_directory) {
+ if (remove_path(path) && errno != ENOENT)
+ return -1;
+ }
+ return 0;
+}
+
+static char *unique_path(struct merge_options *o, 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(&o->current_file_set, newpath) ||
+ string_list_has_string(&o->current_directory_set, newpath) ||
+ lstat(newpath, &st) == 0)
+ sprintf(p, "_%d", suffix++);
+
+ string_list_insert(newpath, &o->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 would_lose_untracked(const char *path)
+{
+ int pos = cache_name_pos(path, strlen(path));
+
+ if (pos < 0)
+ pos = -1 - pos;
+ while (pos < active_nr &&
+ !strcmp(path, active_cache[pos]->name)) {
+ /*
+ * If stage #0, it is definitely tracked.
+ * If it has stage #2 then it was tracked
+ * before this merge started. All other
+ * cases the path was not tracked.
+ */
+ switch (ce_stage(active_cache[pos])) {
+ case 0:
+ case 2:
+ return 0;
+ }
+ pos++;
+ }
+ return file_exists(path);
+}
+
+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, "");
+ }
+
+ /*
+ * Do not unlink a file in the work tree if we are not
+ * tracking it.
+ */
+ if (would_lose_untracked(path))
+ return error("refusing to lose untracked file at '%s'",
+ 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(struct merge_options *o,
+ const unsigned char *sha,
+ unsigned mode,
+ const char *path,
+ int update_cache,
+ int update_wd)
+{
+ if (o->call_depth)
+ 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;
+ 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);
+ if (symlink(lnk, path))
+ die("failed to symlink %s: %s", path, strerror(errno));
+ 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(struct merge_options *o,
+ int clean,
+ const unsigned char *sha,
+ unsigned mode,
+ const char *path)
+{
+ update_file_flags(o, sha, mode, path, o->call_depth || clean, !o->call_depth);
+}
+
+/* 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(struct merge_options *o,
+ mmbuffer_t *result_buf,
+ struct diff_filespec *one,
+ 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(one->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,
+ o->call_depth);
+
+ free(name1);
+ free(name2);
+ free(orig.ptr);
+ free(src1.ptr);
+ free(src2.ptr);
+ return merge_status;
+}
+
+static struct merge_file_info merge_file(struct merge_options *o,
+ struct diff_filespec *one,
+ 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, one->sha1) && !sha_eq(b->sha1, one->sha1))
+ result.merge = 1;
+
+ /*
+ * Merge modes
+ */
+ if (a->mode == b->mode || a->mode == one->mode)
+ result.mode = b->mode;
+ else {
+ result.mode = a->mode;
+ if (b->mode != one->mode) {
+ result.clean = 0;
+ result.merge = 1;
+ }
+ }
+
+ if (sha_eq(a->sha1, b->sha1) || sha_eq(a->sha1, one->sha1))
+ hashcpy(result.sha, b->sha1);
+ else if (sha_eq(b->sha1, one->sha1))
+ hashcpy(result.sha, a->sha1);
+ else if (S_ISREG(a->mode)) {
+ mmbuffer_t result_buf;
+ int merge_status;
+
+ merge_status = merge_3way(o, &result_buf, one, 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 merge_options *o,
+ 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(&o->current_directory_set, ren1_dst)) {
+ dst_name1 = del[delp++] = unique_path(o, ren1_dst, branch1);
+ output(o, 1, "%s is a directory in %s adding as %s instead",
+ ren1_dst, branch2, dst_name1);
+ remove_file(o, 0, ren1_dst, 0);
+ }
+ if (string_list_has_string(&o->current_directory_set, ren2_dst)) {
+ dst_name2 = del[delp++] = unique_path(o, ren2_dst, branch2);
+ output(o, 1, "%s is a directory in %s adding as %s instead",
+ ren2_dst, branch1, dst_name2);
+ remove_file(o, 0, ren2_dst, 0);
+ }
+ if (o->call_depth) {
+ remove_file_from_cache(dst_name1);
+ remove_file_from_cache(dst_name2);
+ /*
+ * Uncomment to leave the conflicting names in the resulting tree
+ *
+ * update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, dst_name1);
+ * update_file(o, 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 merge_options *o,
+ struct rename *ren1,
+ const char *branch1)
+{
+ char *new_path = unique_path(o, ren1->pair->two->path, branch1);
+ output(o, 1, "Renaming %s to %s instead", ren1->pair->one->path, new_path);
+ remove_file(o, 0, ren1->pair->two->path, 0);
+ update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path);
+ free(new_path);
+}
+
+static void conflict_rename_rename_2(struct merge_options *o,
+ struct rename *ren1,
+ const char *branch1,
+ struct rename *ren2,
+ const char *branch2)
+{
+ char *new_path1 = unique_path(o, ren1->pair->two->path, branch1);
+ char *new_path2 = unique_path(o, ren2->pair->two->path, branch2);
+ output(o, 1, "Renaming %s to %s and %s to %s instead",
+ ren1->pair->one->path, new_path1,
+ ren2->pair->one->path, new_path2);
+ remove_file(o, 0, ren1->pair->two->path, 0);
+ update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, new_path1);
+ update_file(o, 0, ren2->pair->two->sha1, ren2->pair->two->mode, new_path2);
+ free(new_path2);
+ free(new_path1);
+}
+
+static int process_renames(struct merge_options *o,
+ struct string_list *a_renames,
+ struct string_list *b_renames)
+{
+ 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 = o->branch1;
+ branch2 = o->branch2;
+ } else {
+ struct rename *tmp;
+ renames1 = b_renames;
+ renames2 = a_renames;
+ renames2Dst = &a_by_dst;
+ branch1 = o->branch2;
+ branch2 = o->branch1;
+ 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(o, 1, "CONFLICT (rename/rename): "
+ "Rename \"%s\"->\"%s\" in branch \"%s\" "
+ "rename \"%s\"->\"%s\" in \"%s\"%s",
+ src, ren1_dst, branch1,
+ src, ren2_dst, branch2,
+ o->call_depth ? " (left unresolved)": "");
+ if (o->call_depth) {
+ remove_file_from_cache(src);
+ update_file(o, 0, ren1->pair->one->sha1,
+ ren1->pair->one->mode, src);
+ }
+ conflict_rename_rename(o, ren1, branch1, ren2, branch2);
+ } else {
+ struct merge_file_info mfi;
+ remove_file(o, 1, ren1_src, 1);
+ mfi = merge_file(o,
+ ren1->pair->one,
+ ren1->pair->two,
+ ren2->pair->two,
+ branch1,
+ branch2);
+ if (mfi.merge || !mfi.clean)
+ output(o, 1, "Renaming %s->%s", src, ren1_dst);
+
+ if (mfi.merge)
+ output(o, 2, "Auto-merging %s", ren1_dst);
+
+ if (!mfi.clean) {
+ output(o, 1, "CONFLICT (content): merge conflict in %s",
+ ren1_dst);
+ clean_merge = 0;
+
+ if (!o->call_depth)
+ update_stages(ren1_dst,
+ ren1->pair->one,
+ ren1->pair->two,
+ ren2->pair->two,
+ 1 /* clear */);
+ }
+ update_file(o, 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(o, 1, ren1_src, o->call_depth || 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(&o->current_directory_set, ren1_dst)) {
+ clean_merge = 0;
+ output(o, 1, "CONFLICT (rename/directory): Rename %s->%s in %s "
+ " directory %s added in %s",
+ ren1_src, ren1_dst, branch1,
+ ren1_dst, branch2);
+ conflict_rename_dir(o, ren1, branch1);
+ } else if (sha_eq(src_other.sha1, null_sha1)) {
+ clean_merge = 0;
+ output(o, 1, "CONFLICT (rename/delete): Rename %s->%s in %s "
+ "and deleted in %s",
+ ren1_src, ren1_dst, branch1,
+ branch2);
+ update_file(o, 0, ren1->pair->two->sha1, ren1->pair->two->mode, ren1_dst);
+ update_stages(ren1_dst, NULL,
+ branch1 == o->branch1 ?
+ ren1->pair->two : NULL,
+ branch1 == o->branch1 ?
+ NULL : ren1->pair->two, 1);
+ } else if (!sha_eq(dst_other.sha1, null_sha1)) {
+ const char *new_path;
+ clean_merge = 0;
+ try_merge = 1;
+ output(o, 1, "CONFLICT (rename/add): Rename %s->%s in %s. "
+ "%s added in %s",
+ ren1_src, ren1_dst, branch1,
+ ren1_dst, branch2);
+ new_path = unique_path(o, ren1_dst, branch2);
+ output(o, 1, "Adding as %s instead", new_path);
+ update_file(o, 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(o, 1, "CONFLICT (rename/rename): "
+ "Rename %s->%s in %s. "
+ "Rename %s->%s in %s",
+ ren1_src, ren1_dst, branch1,
+ ren2->pair->one->path, ren2->pair->two->path, branch2);
+ conflict_rename_rename_2(o, ren1, branch1, ren2, branch2);
+ } else
+ try_merge = 1;
+
+ if (try_merge) {
+ struct diff_filespec *one, *a, *b;
+ struct merge_file_info mfi;
+ src_other.path = (char *)ren1_src;
+
+ one = 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, one, a, b,
+ o->branch1, o->branch2);
+
+ 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(o, 3, "Skipped %s (merged same as existing)", ren1_dst);
+ else {
+ if (mfi.merge || !mfi.clean)
+ output(o, 1, "Renaming %s => %s", ren1_src, ren1_dst);
+ if (mfi.merge)
+ output(o, 2, "Auto-merging %s", ren1_dst);
+ if (!mfi.clean) {
+ output(o, 1, "CONFLICT (rename/modify): Merge conflict in %s",
+ ren1_dst);
+ clean_merge = 0;
+
+ if (!o->call_depth)
+ update_stages(ren1_dst,
+ one, a, b, 1);
+ }
+ update_file(o, 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(struct merge_options *o,
+ const char *path, struct stage_data *entry)
+{
+ /*
+ 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(o, 2, "Removing %s", path);
+ /* do not touch working file if it did not exist */
+ remove_file(o, 1, path, !a_sha);
+ } else {
+ /* Deleted in one and changed in the other */
+ clean_merge = 0;
+ if (!a_sha) {
+ output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
+ "and modified in %s. Version %s of %s left in tree.",
+ path, o->branch1,
+ o->branch2, o->branch2, path);
+ update_file(o, 0, b_sha, b_mode, path);
+ } else {
+ output(o, 1, "CONFLICT (delete/modify): %s deleted in %s "
+ "and modified in %s. Version %s of %s left in tree.",
+ path, o->branch2,
+ o->branch1, o->branch1, path);
+ update_file(o, 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 = o->branch1;
+ other_branch = o->branch2;
+ mode = a_mode;
+ sha = a_sha;
+ conf = "file/directory";
+ } else {
+ add_branch = o->branch2;
+ other_branch = o->branch1;
+ mode = b_mode;
+ sha = b_sha;
+ conf = "directory/file";
+ }
+ if (string_list_has_string(&o->current_directory_set, path)) {
+ const char *new_path = unique_path(o, path, add_branch);
+ clean_merge = 0;
+ output(o, 1, "CONFLICT (%s): There is a directory with name %s in %s. "
+ "Adding %s as %s",
+ conf, path, other_branch, path, new_path);
+ remove_file(o, 0, path, 0);
+ update_file(o, 0, sha, mode, new_path);
+ } else {
+ output(o, 2, "Adding %s", path);
+ update_file(o, 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 one, a, b;
+
+ if (!o_sha) {
+ reason = "add/add";
+ o_sha = (unsigned char *)null_sha1;
+ }
+ output(o, 2, "Auto-merging %s", path);
+ one.path = a.path = b.path = (char *)path;
+ hashcpy(one.sha1, o_sha);
+ one.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, &one, &a, &b,
+ o->branch1, o->branch2);
+
+ clean_merge = mfi.clean;
+ if (mfi.clean)
+ update_file(o, 1, mfi.sha, mfi.mode, path);
+ else if (S_ISGITLINK(mfi.mode))
+ output(o, 1, "CONFLICT (submodule): Merge conflict in %s "
+ "- needs %s", path, sha1_to_hex(b.sha1));
+ else {
+ output(o, 1, "CONFLICT (%s): Merge conflict in %s",
+ reason, path);
+
+ if (o->call_depth)
+ update_file(o, 0, mfi.sha, mfi.mode, path);
+ else
+ update_file_flags(o, 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(o, 1, path, !a_mode);
+ } else
+ die("Fatal merge failure, shouldn't happen.");
+
+ return clean_merge;
+}
+
+int merge_trees(struct merge_options *o,
+ struct tree *head,
+ struct tree *merge,
+ struct tree *common,
+ struct tree **result)
+{
+ int code, clean;
+
+ if (o->subtree_merge) {
+ merge = shift_tree_object(head, merge);
+ common = shift_tree_object(head, common);
+ }
+
+ if (sha_eq(common->object.sha1, merge->object.sha1)) {
+ output(o, 0, "Already uptodate!");
+ *result = head;
+ return 1;
+ }
+
+ code = git_merge_trees(o->call_depth, 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(&o->current_file_set, 1);
+ string_list_clear(&o->current_directory_set, 1);
+ get_files_dirs(o, head);
+ get_files_dirs(o, merge);
+
+ entries = get_unmerged();
+ re_head = get_renames(o, head, common, head, merge, entries);
+ re_merge = get_renames(o, merge, common, head, merge, entries);
+ clean = process_renames(o, re_head, re_merge);
+ 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(o, path, e))
+ clean = 0;
+ }
+
+ string_list_clear(re_merge, 0);
+ string_list_clear(re_head, 0);
+ string_list_clear(entries, 1);
+
+ }
+ else
+ clean = 1;
+
+ if (o->call_depth)
+ *result = write_tree_from_memory(o);
+
+ 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 merge_options *o,
+ struct commit *h1,
+ struct commit *h2,
+ struct commit_list *ca,
+ struct commit **result)
+{
+ struct commit_list *iter;
+ struct commit *merged_common_ancestors;
+ struct tree *mrtree = mrtree;
+ int clean;
+
+ if (show(o, 4)) {
+ output(o, 4, "Merging:");
+ output_commit_title(o, h1);
+ output_commit_title(o, h2);
+ }
+
+ if (!ca) {
+ ca = get_merge_bases(h1, h2, 1);
+ ca = reverse_commit_list(ca);
+ }
+
+ if (show(o, 5)) {
+ output(o, 5, "found %u common ancestor(s):", commit_list_count(ca));
+ for (iter = ca; iter; iter = iter->next)
+ output_commit_title(o, 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) {
+ const char *saved_b1, *saved_b2;
+ o->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();
+ saved_b1 = o->branch1;
+ saved_b2 = o->branch2;
+ o->branch1 = "Temporary merge branch 1";
+ o->branch2 = "Temporary merge branch 2";
+ merge_recursive(o, merged_common_ancestors, iter->item,
+ NULL, &merged_common_ancestors);
+ o->branch1 = saved_b1;
+ o->branch2 = saved_b2;
+ o->call_depth--;
+
+ if (!merged_common_ancestors)
+ die("merge returned no commit");
+ }
+
+ discard_cache();
+ if (!o->call_depth)
+ read_cache();
+
+ clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
+ &mrtree);
+
+ if (o->call_depth) {
+ *result = make_virtual_commit(mrtree, "merged tree");
+ commit_list_insert(h1, &(*result)->parents);
+ commit_list_insert(h2, &(*result)->parents->next);
+ }
+ flush_output(o);
+ return clean;
+}
+
+static struct commit *get_ref(const unsigned char *sha1, const char *name)
+{
+ struct object *object;
+
+ object = deref_tag(parse_object(sha1), name, strlen(name));
+ if (!object)
+ return NULL;
+ if (object->type == OBJ_TREE)
+ return make_virtual_commit((struct tree*)object, name);
+ if (object->type != OBJ_COMMIT)
+ return NULL;
+ if (parse_commit((struct commit *)object))
+ return NULL;
+ return (struct commit *)object;
+}
+
+int merge_recursive_generic(struct merge_options *o,
+ const unsigned char *head,
+ const unsigned char *merge,
+ int num_base_list,
+ const unsigned char **base_list,
+ struct commit **result)
+{
+ int clean, index_fd;
+ struct lock_file *lock = xcalloc(1, sizeof(struct lock_file));
+ struct commit *head_commit = get_ref(head, o->branch1);
+ struct commit *next_commit = get_ref(merge, o->branch2);
+ struct commit_list *ca = NULL;
+
+ if (base_list) {
+ int i;
+ for (i = 0; i < num_base_list; ++i) {
+ struct commit *base;
+ if (!(base = get_ref(base_list[i], sha1_to_hex(base_list[i]))))
+ return error("Could not parse object '%s'",
+ sha1_to_hex(base_list[i]));
+ commit_list_insert(base, &ca);
+ }
+ }
+
+ index_fd = hold_locked_index(lock, 1);
+ clean = merge_recursive(o, head_commit, next_commit, ca,
+ result);
+ if (active_cache_changed &&
+ (write_cache(index_fd, active_cache, active_nr) ||
+ commit_locked_index(lock)))
+ return error("Unable to write index.");
+
+ return clean ? 0 : 1;
+}
+
+static int merge_recursive_config(const char *var, const char *value, void *cb)
+{
+ struct merge_options *o = cb;
+ if (!strcasecmp(var, "merge.verbosity")) {
+ o->verbosity = git_config_int(var, value);
+ return 0;
+ }
+ if (!strcasecmp(var, "diff.renamelimit")) {
+ o->diff_rename_limit = git_config_int(var, value);
+ return 0;
+ }
+ if (!strcasecmp(var, "merge.renamelimit")) {
+ o->merge_rename_limit = git_config_int(var, value);
+ return 0;
+ }
+ return git_xmerge_config(var, value, cb);
+}
+
+void init_merge_options(struct merge_options *o)
+{
+ memset(o, 0, sizeof(struct merge_options));
+ o->verbosity = 2;
+ o->buffer_output = 1;
+ o->diff_rename_limit = -1;
+ o->merge_rename_limit = -1;
+ git_config(merge_recursive_config, o);
+ if (getenv("GIT_MERGE_VERBOSITY"))
+ o->verbosity =
+ strtol(getenv("GIT_MERGE_VERBOSITY"), NULL, 10);
+ if (o->verbosity >= 5)
+ o->buffer_output = 0;
+ strbuf_init(&o->obuf, 0);
+ memset(&o->current_file_set, 0, sizeof(struct string_list));
+ o->current_file_set.strdup_strings = 1;
+ memset(&o->current_directory_set, 0, sizeof(struct string_list));
+ o->current_directory_set.strdup_strings = 1;
+}