]> git.ipfire.org Git - thirdparty/git.git/blobdiff - merge-ort.c
Merge branch 'en/merge-ort-3'
[thirdparty/git.git] / merge-ort.c
index 31103d214074f388af870a5cd400d657da93c0b7..d36a92b59b76fe49424ae97e4cd2777badb7e318 100644 (file)
@@ -48,6 +48,25 @@ enum merge_side {
        MERGE_SIDE2 = 2
 };
 
+struct rename_info {
+       /*
+        * pairs: pairing of filenames from diffcore_rename()
+        *
+        * Index 1 and 2 correspond to sides 1 & 2 as used in
+        * conflict_info.stages.  Index 0 unused.
+        */
+       struct diff_queue_struct pairs[3];
+
+       /*
+        * needed_limit: value needed for inexact rename detection to run
+        *
+        * If the current rename limit wasn't high enough for inexact
+        * rename detection to run, this records the limit needed.  Otherwise,
+        * this value remains 0.
+        */
+       int needed_limit;
+};
+
 struct merge_options_internal {
        /*
         * paths: primary data structure in all of merge ort.
@@ -115,6 +134,11 @@ struct merge_options_internal {
         */
        struct strmap output;
 
+       /*
+        * renames: various data relating to rename detection
+        */
+       struct rename_info renames;
+
        /*
         * current_dir_name: temporary var used in collect_merge_info_callback()
         *
@@ -623,20 +647,397 @@ static int handle_content_merge(struct merge_options *opt,
 
 /*** Function Grouping: functions related to regular rename detection ***/
 
+static int process_renames(struct merge_options *opt,
+                          struct diff_queue_struct *renames)
+{
+       int clean_merge = 1, i;
+
+       for (i = 0; i < renames->nr; ++i) {
+               const char *oldpath = NULL, *newpath;
+               struct diff_filepair *pair = renames->queue[i];
+               struct conflict_info *oldinfo = NULL, *newinfo = NULL;
+               struct strmap_entry *old_ent, *new_ent;
+               unsigned int old_sidemask;
+               int target_index, other_source_index;
+               int source_deleted, collision, type_changed;
+               const char *rename_branch = NULL, *delete_branch = NULL;
+
+               old_ent = strmap_get_entry(&opt->priv->paths, pair->one->path);
+               oldpath = old_ent->key;
+               oldinfo = old_ent->value;
+
+               new_ent = strmap_get_entry(&opt->priv->paths, pair->two->path);
+               newpath = new_ent->key;
+               newinfo = new_ent->value;
+
+               /*
+                * diff_filepairs have copies of pathnames, thus we have to
+                * use standard 'strcmp()' (negated) instead of '=='.
+                */
+               if (i + 1 < renames->nr &&
+                   !strcmp(oldpath, renames->queue[i+1]->one->path)) {
+                       /* Handle rename/rename(1to2) or rename/rename(1to1) */
+                       const char *pathnames[3];
+                       struct version_info merged;
+                       struct conflict_info *base, *side1, *side2;
+                       unsigned was_binary_blob = 0;
+
+                       pathnames[0] = oldpath;
+                       pathnames[1] = newpath;
+                       pathnames[2] = renames->queue[i+1]->two->path;
+
+                       base = strmap_get(&opt->priv->paths, pathnames[0]);
+                       side1 = strmap_get(&opt->priv->paths, pathnames[1]);
+                       side2 = strmap_get(&opt->priv->paths, pathnames[2]);
+
+                       VERIFY_CI(base);
+                       VERIFY_CI(side1);
+                       VERIFY_CI(side2);
+
+                       if (!strcmp(pathnames[1], pathnames[2])) {
+                               /* Both sides renamed the same way */
+                               assert(side1 == side2);
+                               memcpy(&side1->stages[0], &base->stages[0],
+                                      sizeof(merged));
+                               side1->filemask |= (1 << MERGE_BASE);
+                               /* Mark base as resolved by removal */
+                               base->merged.is_null = 1;
+                               base->merged.clean = 1;
+
+                               /* We handled both renames, i.e. i+1 handled */
+                               i++;
+                               /* Move to next rename */
+                               continue;
+                       }
+
+                       /* This is a rename/rename(1to2) */
+                       clean_merge = handle_content_merge(opt,
+                                                          pair->one->path,
+                                                          &base->stages[0],
+                                                          &side1->stages[1],
+                                                          &side2->stages[2],
+                                                          pathnames,
+                                                          1 + 2 * opt->priv->call_depth,
+                                                          &merged);
+                       if (!clean_merge &&
+                           merged.mode == side1->stages[1].mode &&
+                           oideq(&merged.oid, &side1->stages[1].oid))
+                               was_binary_blob = 1;
+                       memcpy(&side1->stages[1], &merged, sizeof(merged));
+                       if (was_binary_blob) {
+                               /*
+                                * Getting here means we were attempting to
+                                * merge a binary blob.
+                                *
+                                * Since we can't merge binaries,
+                                * handle_content_merge() just takes one
+                                * side.  But we don't want to copy the
+                                * contents of one side to both paths.  We
+                                * used the contents of side1 above for
+                                * side1->stages, let's use the contents of
+                                * side2 for side2->stages below.
+                                */
+                               oidcpy(&merged.oid, &side2->stages[2].oid);
+                               merged.mode = side2->stages[2].mode;
+                       }
+                       memcpy(&side2->stages[2], &merged, sizeof(merged));
+
+                       side1->path_conflict = 1;
+                       side2->path_conflict = 1;
+                       /*
+                        * TODO: For renames we normally remove the path at the
+                        * old name.  It would thus seem consistent to do the
+                        * same for rename/rename(1to2) cases, but we haven't
+                        * done so traditionally and a number of the regression
+                        * tests now encode an expectation that the file is
+                        * left there at stage 1.  If we ever decide to change
+                        * this, add the following two lines here:
+                        *    base->merged.is_null = 1;
+                        *    base->merged.clean = 1;
+                        * and remove the setting of base->path_conflict to 1.
+                        */
+                       base->path_conflict = 1;
+                       path_msg(opt, oldpath, 0,
+                                _("CONFLICT (rename/rename): %s renamed to "
+                                  "%s in %s and to %s in %s."),
+                                pathnames[0],
+                                pathnames[1], opt->branch1,
+                                pathnames[2], opt->branch2);
+
+                       i++; /* We handled both renames, i.e. i+1 handled */
+                       continue;
+               }
+
+               VERIFY_CI(oldinfo);
+               VERIFY_CI(newinfo);
+               target_index = pair->score; /* from collect_renames() */
+               assert(target_index == 1 || target_index == 2);
+               other_source_index = 3 - target_index;
+               old_sidemask = (1 << other_source_index); /* 2 or 4 */
+               source_deleted = (oldinfo->filemask == 1);
+               collision = ((newinfo->filemask & old_sidemask) != 0);
+               type_changed = !source_deleted &&
+                       (S_ISREG(oldinfo->stages[other_source_index].mode) !=
+                        S_ISREG(newinfo->stages[target_index].mode));
+               if (type_changed && collision) {
+                       /*
+                        * special handling so later blocks can handle this...
+                        *
+                        * if type_changed && collision are both true, then this
+                        * was really a double rename, but one side wasn't
+                        * detected due to lack of break detection.  I.e.
+                        * something like
+                        *    orig: has normal file 'foo'
+                        *    side1: renames 'foo' to 'bar', adds 'foo' symlink
+                        *    side2: renames 'foo' to 'bar'
+                        * In this case, the foo->bar rename on side1 won't be
+                        * detected because the new symlink named 'foo' is
+                        * there and we don't do break detection.  But we detect
+                        * this here because we don't want to merge the content
+                        * of the foo symlink with the foo->bar file, so we
+                        * have some logic to handle this special case.  The
+                        * easiest way to do that is make 'bar' on side1 not
+                        * be considered a colliding file but the other part
+                        * of a normal rename.  If the file is very different,
+                        * well we're going to get content merge conflicts
+                        * anyway so it doesn't hurt.  And if the colliding
+                        * file also has a different type, that'll be handled
+                        * by the content merge logic in process_entry() too.
+                        *
+                        * See also t6430, 'rename vs. rename/symlink'
+                        */
+                       collision = 0;
+               }
+               if (source_deleted) {
+                       if (target_index == 1) {
+                               rename_branch = opt->branch1;
+                               delete_branch = opt->branch2;
+                       } else {
+                               rename_branch = opt->branch2;
+                               delete_branch = opt->branch1;
+                       }
+               }
+
+               assert(source_deleted || oldinfo->filemask & old_sidemask);
+
+               /* Need to check for special types of rename conflicts... */
+               if (collision && !source_deleted) {
+                       /* collision: rename/add or rename/rename(2to1) */
+                       const char *pathnames[3];
+                       struct version_info merged;
+
+                       struct conflict_info *base, *side1, *side2;
+                       unsigned clean;
+
+                       pathnames[0] = oldpath;
+                       pathnames[other_source_index] = oldpath;
+                       pathnames[target_index] = newpath;
+
+                       base = strmap_get(&opt->priv->paths, pathnames[0]);
+                       side1 = strmap_get(&opt->priv->paths, pathnames[1]);
+                       side2 = strmap_get(&opt->priv->paths, pathnames[2]);
+
+                       VERIFY_CI(base);
+                       VERIFY_CI(side1);
+                       VERIFY_CI(side2);
+
+                       clean = handle_content_merge(opt, pair->one->path,
+                                                    &base->stages[0],
+                                                    &side1->stages[1],
+                                                    &side2->stages[2],
+                                                    pathnames,
+                                                    1 + 2 * opt->priv->call_depth,
+                                                    &merged);
+
+                       memcpy(&newinfo->stages[target_index], &merged,
+                              sizeof(merged));
+                       if (!clean) {
+                               path_msg(opt, newpath, 0,
+                                        _("CONFLICT (rename involved in "
+                                          "collision): rename of %s -> %s has "
+                                          "content conflicts AND collides "
+                                          "with another path; this may result "
+                                          "in nested conflict markers."),
+                                        oldpath, newpath);
+                       }
+               } else if (collision && source_deleted) {
+                       /*
+                        * rename/add/delete or rename/rename(2to1)/delete:
+                        * since oldpath was deleted on the side that didn't
+                        * do the rename, there's not much of a content merge
+                        * we can do for the rename.  oldinfo->merged.is_null
+                        * was already set, so we just leave things as-is so
+                        * they look like an add/add conflict.
+                        */
+
+                       newinfo->path_conflict = 1;
+                       path_msg(opt, newpath, 0,
+                                _("CONFLICT (rename/delete): %s renamed "
+                                  "to %s in %s, but deleted in %s."),
+                                oldpath, newpath, rename_branch, delete_branch);
+               } else {
+                       /*
+                        * a few different cases...start by copying the
+                        * existing stage(s) from oldinfo over the newinfo
+                        * and update the pathname(s).
+                        */
+                       memcpy(&newinfo->stages[0], &oldinfo->stages[0],
+                              sizeof(newinfo->stages[0]));
+                       newinfo->filemask |= (1 << MERGE_BASE);
+                       newinfo->pathnames[0] = oldpath;
+                       if (type_changed) {
+                               /* rename vs. typechange */
+                               /* Mark the original as resolved by removal */
+                               memcpy(&oldinfo->stages[0].oid, &null_oid,
+                                      sizeof(oldinfo->stages[0].oid));
+                               oldinfo->stages[0].mode = 0;
+                               oldinfo->filemask &= 0x06;
+                       } else if (source_deleted) {
+                               /* rename/delete */
+                               newinfo->path_conflict = 1;
+                               path_msg(opt, newpath, 0,
+                                        _("CONFLICT (rename/delete): %s renamed"
+                                          " to %s in %s, but deleted in %s."),
+                                        oldpath, newpath,
+                                        rename_branch, delete_branch);
+                       } else {
+                               /* normal rename */
+                               memcpy(&newinfo->stages[other_source_index],
+                                      &oldinfo->stages[other_source_index],
+                                      sizeof(newinfo->stages[0]));
+                               newinfo->filemask |= (1 << other_source_index);
+                               newinfo->pathnames[other_source_index] = oldpath;
+                       }
+               }
+
+               if (!type_changed) {
+                       /* Mark the original as resolved by removal */
+                       oldinfo->merged.is_null = 1;
+                       oldinfo->merged.clean = 1;
+               }
+
+       }
+
+       return clean_merge;
+}
+
+static int compare_pairs(const void *a_, const void *b_)
+{
+       const struct diff_filepair *a = *((const struct diff_filepair **)a_);
+       const struct diff_filepair *b = *((const struct diff_filepair **)b_);
+
+       return strcmp(a->one->path, b->one->path);
+}
+
+/* Call diffcore_rename() to compute which files have changed on given side */
+static void detect_regular_renames(struct merge_options *opt,
+                                  struct tree *merge_base,
+                                  struct tree *side,
+                                  unsigned side_index)
+{
+       struct diff_options diff_opts;
+       struct rename_info *renames = &opt->priv->renames;
+
+       repo_diff_setup(opt->repo, &diff_opts);
+       diff_opts.flags.recursive = 1;
+       diff_opts.flags.rename_empty = 0;
+       diff_opts.detect_rename = DIFF_DETECT_RENAME;
+       diff_opts.rename_limit = opt->rename_limit;
+       if (opt->rename_limit <= 0)
+               diff_opts.rename_limit = 1000;
+       diff_opts.rename_score = opt->rename_score;
+       diff_opts.show_rename_progress = opt->show_rename_progress;
+       diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
+       diff_setup_done(&diff_opts);
+       diff_tree_oid(&merge_base->object.oid, &side->object.oid, "",
+                     &diff_opts);
+       diffcore_std(&diff_opts);
+
+       if (diff_opts.needed_rename_limit > renames->needed_limit)
+               renames->needed_limit = diff_opts.needed_rename_limit;
+
+       renames->pairs[side_index] = diff_queued_diff;
+
+       diff_opts.output_format = DIFF_FORMAT_NO_OUTPUT;
+       diff_queued_diff.nr = 0;
+       diff_queued_diff.queue = NULL;
+       diff_flush(&diff_opts);
+}
+
+/*
+ * Get information of all renames which occurred in 'side_pairs', discarding
+ * non-renames.
+ */
+static int collect_renames(struct merge_options *opt,
+                          struct diff_queue_struct *result,
+                          unsigned side_index)
+{
+       int i, clean = 1;
+       struct diff_queue_struct *side_pairs;
+       struct rename_info *renames = &opt->priv->renames;
+
+       side_pairs = &renames->pairs[side_index];
+
+       for (i = 0; i < side_pairs->nr; ++i) {
+               struct diff_filepair *p = side_pairs->queue[i];
+
+               if (p->status != 'R') {
+                       diff_free_filepair(p);
+                       continue;
+               }
+
+               /*
+                * p->score comes back from diffcore_rename_extended() with
+                * the similarity of the renamed file.  The similarity is
+                * was used to determine that the two files were related
+                * and are a rename, which we have already used, but beyond
+                * that we have no use for the similarity.  So p->score is
+                * now irrelevant.  However, process_renames() will need to
+                * know which side of the merge this rename was associated
+                * with, so overwrite p->score with that value.
+                */
+               p->score = side_index;
+               result->queue[result->nr++] = p;
+       }
+
+       return clean;
+}
+
 static int detect_and_process_renames(struct merge_options *opt,
                                      struct tree *merge_base,
                                      struct tree *side1,
                                      struct tree *side2)
 {
-       int clean = 1;
+       struct diff_queue_struct combined;
+       struct rename_info *renames = &opt->priv->renames;
+       int s, clean = 1;
+
+       memset(&combined, 0, sizeof(combined));
+
+       detect_regular_renames(opt, merge_base, side1, MERGE_SIDE1);
+       detect_regular_renames(opt, merge_base, side2, MERGE_SIDE2);
+
+       ALLOC_GROW(combined.queue,
+                  renames->pairs[1].nr + renames->pairs[2].nr,
+                  combined.alloc);
+       clean &= collect_renames(opt, &combined, MERGE_SIDE1);
+       clean &= collect_renames(opt, &combined, MERGE_SIDE2);
+       QSORT(combined.queue, combined.nr, compare_pairs);
+
+       clean &= process_renames(opt, &combined);
+
+       /* Free memory for renames->pairs[] and combined */
+       for (s = MERGE_SIDE1; s <= MERGE_SIDE2; s++) {
+               free(renames->pairs[s].queue);
+               DIFF_QUEUE_CLEAR(&renames->pairs[s]);
+       }
+       if (combined.nr) {
+               int i;
+               for (i = 0; i < combined.nr; i++)
+                       diff_free_filepair(combined.queue[i]);
+               free(combined.queue);
+       }
 
-       /*
-        * Rename detection works by detecting file similarity.  Here we use
-        * a really easy-to-implement scheme: files are similar IFF they have
-        * the same filename.  Therefore, by this scheme, there are no renames.
-        *
-        * TODO: Actually implement a real rename detection scheme.
-        */
        return clean;
 }
 
@@ -1038,24 +1439,33 @@ static void process_entry(struct merge_options *opt,
                modify_branch = (side == 1) ? opt->branch1 : opt->branch2;
                delete_branch = (side == 1) ? opt->branch2 : opt->branch1;
 
-               path_msg(opt, path, 0,
-                        _("CONFLICT (modify/delete): %s deleted in %s "
-                          "and modified in %s.  Version %s of %s left "
-                          "in tree."),
-                        path, delete_branch, modify_branch,
-                        modify_branch, path);
+               if (ci->path_conflict &&
+                   oideq(&ci->stages[0].oid, &ci->stages[side].oid)) {
+                       /*
+                        * This came from a rename/delete; no action to take,
+                        * but avoid printing "modify/delete" conflict notice
+                        * since the contents were not modified.
+                        */
+               } else {
+                       path_msg(opt, path, 0,
+                                _("CONFLICT (modify/delete): %s deleted in %s "
+                                  "and modified in %s.  Version %s of %s left "
+                                  "in tree."),
+                                path, delete_branch, modify_branch,
+                                modify_branch, path);
+               }
        } else if (ci->filemask == 2 || ci->filemask == 4) {
                /* Added on one side */
                int side = (ci->filemask == 4) ? 2 : 1;
                ci->merged.result.mode = ci->stages[side].mode;
                oidcpy(&ci->merged.result.oid, &ci->stages[side].oid);
-               ci->merged.clean = !ci->df_conflict;
+               ci->merged.clean = !ci->df_conflict && !ci->path_conflict;
        } else if (ci->filemask == 1) {
                /* Deleted on both sides */
                ci->merged.is_null = 1;
                ci->merged.result.mode = 0;
                oidcpy(&ci->merged.result.oid, &null_oid);
-               ci->merged.clean = 1;
+               ci->merged.clean = !ci->path_conflict;
        }
 
        /*
@@ -1333,6 +1743,10 @@ void merge_switch_to_result(struct merge_options *opt,
                        printf("%s", sb->buf);
                }
                string_list_clear(&olist, 0);
+
+               /* Also include needed rename limit adjustment now */
+               diff_warn_rename_limit("merge.renamelimit",
+                                      opti->renames.needed_limit, 0);
        }
 
        merge_finalize(opt, result);