Documentation: remove stray backslash in show-branch discussion
[gitweb.git] / merge-recursive.c
index b97026bd5cc1d2ef1b46a9ef3dcd7562ad52c377..6cff9cdc86b1db7c4bd0a75175a77b2474417dfb 100644 (file)
@@ -3,6 +3,7 @@
  * Fredrik Kuivinen.
  * The thieves were Alex Riesen and Johannes Schindelin, in June/July 2006
  */
+#include "advice.h"
 #include "cache.h"
 #include "cache-tree.h"
 #include "commit.h"
 #include "merge-recursive.h"
 #include "dir.h"
 
-static struct tree *shift_tree_object(struct tree *one, struct tree *two)
+static struct tree *shift_tree_object(struct tree *one, struct tree *two,
+                                     const char *subtree_shift)
 {
        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 (!*subtree_shift) {
+               shift_tree(one->object.sha1, two->object.sha1, shifted, 0);
+       } else {
+               shift_tree_by(one->object.sha1, two->object.sha1, shifted,
+                             subtree_shift);
+       }
        if (!hashcmp(two->object.sha1, shifted))
                return two;
        return lookup_tree(shifted);
@@ -38,7 +41,7 @@ static struct tree *shift_tree_object(struct tree *one, struct tree *two)
  * A virtual commit has (const char *)commit->util set to the name.
  */
 
-struct commit *make_virtual_commit(struct tree *tree, const char *comment)
+static struct commit *make_virtual_commit(struct tree *tree, const char *comment)
 {
        struct commit *commit = xcalloc(1, sizeof(struct commit));
        commit->tree = tree;
@@ -86,6 +89,7 @@ static void flush_output(struct merge_options *o)
        }
 }
 
+__attribute__((format (printf, 3, 4)))
 static void output(struct merge_options *o, int v, const char *fmt, ...)
 {
        int len;
@@ -132,16 +136,10 @@ static void output_commit_title(struct merge_options *o, struct commit *commit)
                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);
+                       const char *title;
+                       int len = find_commit_subject(commit->buffer, &title);
+                       if (len)
+                               printf("%.*s\n", len, title);
                }
        }
 }
@@ -181,6 +179,7 @@ static int git_merge_trees(int index_only,
        opts.fn = threeway_merge;
        opts.src_index = &the_index;
        opts.dst_index = &the_index;
+       opts.msgs = get_porcelain_error_msgs();
 
        init_tree_desc_from_tree(t+0, common);
        init_tree_desc_from_tree(t+1, head);
@@ -197,13 +196,14 @@ struct tree *write_tree_from_memory(struct merge_options *o)
 
        if (unmerged_cache()) {
                int i;
-               output(o, 0, "There are unmerged index entries:");
+               fprintf(stderr, "BUG: There are unmerged index entries:\n");
                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);
+                               fprintf(stderr, "BUG: %d %.*s", ce_stage(ce),
+                                       (int)ce_namelen(ce), ce->name);
                }
-               return NULL;
+               die("Bug in merge-recursive.c");
        }
 
        if (!active_cache_tree)
@@ -232,12 +232,12 @@ static int save_files_dirs(const unsigned char *sha1,
        newpath[baselen + len] = '\0';
 
        if (S_ISDIR(mode))
-               string_list_insert(newpath, &o->current_directory_set);
+               string_list_insert(&o->current_directory_set, newpath);
        else
-               string_list_insert(newpath, &o->current_file_set);
+               string_list_insert(&o->current_file_set, newpath);
        free(newpath);
 
-       return READ_TREE_RECURSIVE;
+       return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
 }
 
 static int get_files_dirs(struct merge_options *o, struct tree *tree)
@@ -265,7 +265,7 @@ static struct stage_data *insert_stage_data(const char *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 = string_list_insert(entries, path);
        item->util = e;
        return e;
 }
@@ -288,9 +288,9 @@ static struct string_list *get_unmerged(void)
                if (!ce_stage(ce))
                        continue;
 
-               item = string_list_lookup(ce->name, unmerged);
+               item = string_list_lookup(unmerged, ce->name);
                if (!item) {
-                       item = string_list_insert(ce->name, unmerged);
+                       item = string_list_insert(unmerged, ce->name);
                        item->util = xcalloc(1, sizeof(struct stage_data));
                }
                e = item->util;
@@ -350,20 +350,20 @@ static struct string_list *get_renames(struct merge_options *o,
                re = xmalloc(sizeof(*re));
                re->processed = 0;
                re->pair = pair;
-               item = string_list_lookup(re->pair->one->path, entries);
+               item = string_list_lookup(entries, re->pair->one->path);
                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);
+               item = string_list_lookup(entries, re->pair->two->path);
                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 = string_list_insert(renames, pair->one->path);
                item->util = re;
        }
        opts.output_format = DIFF_FORMAT_NO_OUTPUT;
@@ -403,7 +403,7 @@ static int remove_file(struct merge_options *o, int clean,
                        return -1;
        }
        if (update_working_directory) {
-               if (remove_path(path) && errno != ENOENT)
+               if (remove_path(path))
                        return -1;
        }
        return 0;
@@ -426,7 +426,7 @@ static char *unique_path(struct merge_options *o, const char *path, const char *
               lstat(newpath, &st) == 0)
                sprintf(p, "_%d", suffix++);
 
-       string_list_insert(newpath, &o->current_file_set);
+       string_list_insert(&o->current_file_set, newpath);
        return newpath;
 }
 
@@ -438,7 +438,7 @@ static void flush_buffer(int fd, const char *buf, unsigned long size)
                        /* Ignore epipe */
                        if (errno == EPIPE)
                                break;
-                       die("merge-recursive: %s", strerror(errno));
+                       die_errno("merge-recursive");
                } else if (!ret) {
                        die("merge-recursive: disk full?");
                }
@@ -520,8 +520,12 @@ static void update_file_flags(struct merge_options *o,
                unsigned long size;
 
                if (S_ISGITLINK(mode))
-                       die("cannot read object %s '%s': It is a submodule!",
-                           sha1_to_hex(sha), path);
+                       /*
+                        * We may later decide to recursively descend into
+                        * the submodule directory and update its index
+                        * and/or work tree, but we do not do that now.
+                        */
+                       goto update_index;
 
                buf = read_sha1_file(sha, &type, &size);
                if (!buf)
@@ -550,7 +554,7 @@ static void update_file_flags(struct merge_options *o,
                                mode = 0666;
                        fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
                        if (fd < 0)
-                               die("failed to open %s: %s", path, strerror(errno));
+                               die_errno("failed to open '%s'", path);
                        flush_buffer(fd, buf, size);
                        close(fd);
                } else if (S_ISLNK(mode)) {
@@ -558,7 +562,7 @@ static void update_file_flags(struct merge_options *o,
                        safe_create_leading_directories_const(path);
                        unlink(path);
                        if (symlink(lnk, path))
-                               die("failed to symlink %s: %s", path, strerror(errno));
+                               die_errno("failed to symlink '%s'", path);
                        free(lnk);
                } else
                        die("do not know what to do with %06o %s '%s'",
@@ -589,23 +593,6 @@ struct merge_file_info
                 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,
@@ -615,19 +602,46 @@ static int merge_3way(struct merge_options *o,
                      const char *branch2)
 {
        mmfile_t orig, src1, src2;
-       char *name1, *name2;
+       char *base_name, *name1, *name2;
        int merge_status;
+       int favor;
 
-       name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
-       name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
+       if (o->call_depth)
+               favor = 0;
+       else {
+               switch (o->recursive_variant) {
+               case MERGE_RECURSIVE_OURS:
+                       favor = XDL_MERGE_FAVOR_OURS;
+                       break;
+               case MERGE_RECURSIVE_THEIRS:
+                       favor = XDL_MERGE_FAVOR_THEIRS;
+                       break;
+               default:
+                       favor = 0;
+                       break;
+               }
+       }
+
+       if (strcmp(a->path, b->path) ||
+           (o->ancestor != NULL && strcmp(a->path, one->path) != 0)) {
+               base_name = o->ancestor == NULL ? NULL :
+                       xstrdup(mkpath("%s:%s", o->ancestor, one->path));
+               name1 = xstrdup(mkpath("%s:%s", branch1, a->path));
+               name2 = xstrdup(mkpath("%s:%s", branch2, b->path));
+       } else {
+               base_name = o->ancestor == NULL ? NULL :
+                       xstrdup(mkpath("%s", o->ancestor));
+               name1 = xstrdup(mkpath("%s", branch1));
+               name2 = xstrdup(mkpath("%s", branch2));
+       }
 
-       fill_mm(one->sha1, &orig);
-       fill_mm(a->sha1, &src1);
-       fill_mm(b->sha1, &src2);
+       read_mmblob(&orig, one->sha1);
+       read_mmblob(&src1, a->sha1);
+       read_mmblob(&src2, b->sha1);
 
-       merge_status = ll_merge(result_buf, a->path, &orig,
+       merge_status = ll_merge(result_buf, a->path, &orig, base_name,
                                &src1, name1, &src2, name2,
-                               o->call_depth);
+                               (!!o->call_depth) | (favor << 1));
 
        free(name1);
        free(name2);
@@ -786,37 +800,35 @@ static int process_renames(struct merge_options *o,
                           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};
+       struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
+       struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
        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
+               string_list_insert(&a_by_dst, sre->pair->two->path)->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
+               string_list_insert(&b_by_dst, sre->pair->two->path)->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 string_list *renames1, *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);
+                       int compare = strcmp(a_renames->items[i].string,
+                                            b_renames->items[j].string);
                        if (compare <= 0)
                                ren1 = a_renames->items[i++].util;
                        if (compare >= 0)
@@ -826,14 +838,12 @@ static int process_renames(struct merge_options *o,
                /* 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;
@@ -934,11 +944,12 @@ static int process_renames(struct merge_options *o,
                                       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);
+                               if (!o->call_depth)
+                                       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;
@@ -947,10 +958,32 @@ static int process_renames(struct merge_options *o,
                                       "%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))) {
+                               if (o->call_depth) {
+                                       struct merge_file_info mfi;
+                                       struct diff_filespec one, a, b;
+
+                                       one.path = a.path = b.path =
+                                               (char *)ren1_dst;
+                                       hashcpy(one.sha1, null_sha1);
+                                       one.mode = 0;
+                                       hashcpy(a.sha1, ren1->pair->two->sha1);
+                                       a.mode = ren1->pair->two->mode;
+                                       hashcpy(b.sha1, dst_other.sha1);
+                                       b.mode = dst_other.mode;
+                                       mfi = merge_file(o, &one, &a, &b,
+                                                        branch1,
+                                                        branch2);
+                                       output(o, 1, "Adding merged %s", ren1_dst);
+                                       update_file(o, 0,
+                                                   mfi.sha,
+                                                   mfi.mode,
+                                                   ren1_dst);
+                               } else {
+                                       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(renames2Dst, ren1_dst))) {
                                ren2 = item->util;
                                clean_merge = 0;
                                ren2->processed = 1;
@@ -1121,21 +1154,13 @@ static int process_entry(struct merge_options *o,
                                 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 {
+               if (!mfi.clean) {
+                       if (S_ISGITLINK(mfi.mode))
+                               reason = "submodule";
                        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 */);
                }
+               update_file(o, mfi.clean, mfi.sha, mfi.mode, path);
        } else if (!o_sha && !a_sha && !b_sha) {
                /*
                 * this entry was deleted altogether. a_mode == 0 means
@@ -1148,6 +1173,28 @@ static int process_entry(struct merge_options *o,
        return clean_merge;
 }
 
+struct unpack_trees_error_msgs get_porcelain_error_msgs(void)
+{
+       struct unpack_trees_error_msgs msgs = {
+               /* would_overwrite */
+               "Your local changes to '%s' would be overwritten by merge.  Aborting.",
+               /* not_uptodate_file */
+               "Your local changes to '%s' would be overwritten by merge.  Aborting.",
+               /* not_uptodate_dir */
+               "Updating '%s' would lose untracked files in it.  Aborting.",
+               /* would_lose_untracked */
+               "Untracked working tree file '%s' would be %s by merge.  Aborting",
+               /* bind_overlap -- will not happen here */
+               NULL,
+       };
+       if (advice_commit_before_merge) {
+               msgs.would_overwrite = msgs.not_uptodate_file =
+                       "Your local changes to '%s' would be overwritten by merge.  Aborting.\n"
+                       "Please, commit your changes or stash them before you can merge.";
+       }
+       return msgs;
+}
+
 int merge_trees(struct merge_options *o,
                struct tree *head,
                struct tree *merge,
@@ -1156,23 +1203,27 @@ int merge_trees(struct merge_options *o,
 {
        int code, clean;
 
-       if (o->subtree_merge) {
-               merge = shift_tree_object(head, merge);
-               common = shift_tree_object(head, common);
+       if (o->subtree_shift) {
+               merge = shift_tree_object(head, merge, o->subtree_shift);
+               common = shift_tree_object(head, common, o->subtree_shift);
        }
 
        if (sha_eq(common->object.sha1, merge->object.sha1)) {
-               output(o, 0, "Already uptodate!");
+               output(o, 0, "Already up-to-date!");
                *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 (code != 0) {
+               if (show(o, 4) || o->call_depth)
+                       die("merging of trees %s and %s failed",
+                           sha1_to_hex(head->object.sha1),
+                           sha1_to_hex(merge->object.sha1));
+               else
+                       exit(128);
+       }
 
        if (unmerged_cache()) {
                struct string_list *entries, *re_head, *re_merge;
@@ -1291,6 +1342,7 @@ int merge_recursive(struct merge_options *o,
        if (!o->call_depth)
                read_cache();
 
+       o->ancestor = "merged common ancestors";
        clean = merge_trees(o, h1->tree, h2->tree, merged_common_ancestors->tree,
                            &mrtree);