blob: 2fd0aa968751f7defa06a51148f75bb5838b44d4 [file] [log] [blame]
/*
* 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 "merge-recursive.h"
#include "advice.h"
#include "alloc.h"
#include "attr.h"
#include "blob.h"
#include "builtin.h"
#include "cache-tree.h"
#include "commit.h"
#include "commit-reach.h"
#include "config.h"
#include "diff.h"
#include "diffcore.h"
#include "dir.h"
#include "ll-merge.h"
#include "lockfile.h"
#include "object-store.h"
#include "repository.h"
#include "revision.h"
#include "string-list.h"
#include "submodule-config.h"
#include "submodule.h"
#include "tag.h"
#include "tree-walk.h"
#include "unpack-trees.h"
#include "xdiff-interface.h"
struct merge_options_internal {
int call_depth;
int needed_rename_limit;
struct hashmap current_file_dir_set;
struct string_list df_conflict_file_set;
struct unpack_trees_options unpack_opts;
struct index_state orig_index;
};
struct path_hashmap_entry {
struct hashmap_entry e;
char path[FLEX_ARRAY];
};
static int path_hashmap_cmp(const void *cmp_data UNUSED,
const struct hashmap_entry *eptr,
const struct hashmap_entry *entry_or_key,
const void *keydata)
{
const struct path_hashmap_entry *a, *b;
const char *key = keydata;
a = container_of(eptr, const struct path_hashmap_entry, e);
b = container_of(entry_or_key, const struct path_hashmap_entry, e);
return fspathcmp(a->path, key ? key : b->path);
}
/*
* For dir_rename_entry, directory names are stored as a full path from the
* toplevel of the repository and do not include a trailing '/'. Also:
*
* dir: original name of directory being renamed
* non_unique_new_dir: if true, could not determine new_dir
* new_dir: final name of directory being renamed
* possible_new_dirs: temporary used to help determine new_dir; see comments
* in get_directory_renames() for details
*/
struct dir_rename_entry {
struct hashmap_entry ent;
char *dir;
unsigned non_unique_new_dir:1;
struct strbuf new_dir;
struct string_list possible_new_dirs;
};
static struct dir_rename_entry *dir_rename_find_entry(struct hashmap *hashmap,
char *dir)
{
struct dir_rename_entry key;
if (!dir)
return NULL;
hashmap_entry_init(&key.ent, strhash(dir));
key.dir = dir;
return hashmap_get_entry(hashmap, &key, ent, NULL);
}
static int dir_rename_cmp(const void *cmp_data UNUSED,
const struct hashmap_entry *eptr,
const struct hashmap_entry *entry_or_key,
const void *keydata UNUSED)
{
const struct dir_rename_entry *e1, *e2;
e1 = container_of(eptr, const struct dir_rename_entry, ent);
e2 = container_of(entry_or_key, const struct dir_rename_entry, ent);
return strcmp(e1->dir, e2->dir);
}
static void dir_rename_init(struct hashmap *map)
{
hashmap_init(map, dir_rename_cmp, NULL, 0);
}
static void dir_rename_entry_init(struct dir_rename_entry *entry,
char *directory)
{
hashmap_entry_init(&entry->ent, strhash(directory));
entry->dir = directory;
entry->non_unique_new_dir = 0;
strbuf_init(&entry->new_dir, 0);
string_list_init_nodup(&entry->possible_new_dirs);
}
struct collision_entry {
struct hashmap_entry ent;
char *target_file;
struct string_list source_files;
unsigned reported_already:1;
};
static struct collision_entry *collision_find_entry(struct hashmap *hashmap,
char *target_file)
{
struct collision_entry key;
hashmap_entry_init(&key.ent, strhash(target_file));
key.target_file = target_file;
return hashmap_get_entry(hashmap, &key, ent, NULL);
}
static int collision_cmp(const void *cmp_data UNUSED,
const struct hashmap_entry *eptr,
const struct hashmap_entry *entry_or_key,
const void *keydata UNUSED)
{
const struct collision_entry *e1, *e2;
e1 = container_of(eptr, const struct collision_entry, ent);
e2 = container_of(entry_or_key, const struct collision_entry, ent);
return strcmp(e1->target_file, e2->target_file);
}
static void collision_init(struct hashmap *map)
{
hashmap_init(map, collision_cmp, NULL, 0);
}
static void flush_output(struct merge_options *opt)
{
if (opt->buffer_output < 2 && opt->obuf.len) {
fputs(opt->obuf.buf, stdout);
strbuf_reset(&opt->obuf);
}
}
__attribute__((format (printf, 2, 3)))
static int err(struct merge_options *opt, const char *err, ...)
{
va_list params;
if (opt->buffer_output < 2)
flush_output(opt);
else {
strbuf_complete(&opt->obuf, '\n');
strbuf_addstr(&opt->obuf, "error: ");
}
va_start(params, err);
strbuf_vaddf(&opt->obuf, err, params);
va_end(params);
if (opt->buffer_output > 1)
strbuf_addch(&opt->obuf, '\n');
else {
error("%s", opt->obuf.buf);
strbuf_reset(&opt->obuf);
}
return -1;
}
static struct tree *shift_tree_object(struct repository *repo,
struct tree *one, struct tree *two,
const char *subtree_shift)
{
struct object_id shifted;
if (!*subtree_shift) {
shift_tree(repo, &one->object.oid, &two->object.oid, &shifted, 0);
} else {
shift_tree_by(repo, &one->object.oid, &two->object.oid, &shifted,
subtree_shift);
}
if (oideq(&two->object.oid, &shifted))
return two;
return lookup_tree(repo, &shifted);
}
static inline void set_commit_tree(struct commit *c, struct tree *t)
{
c->maybe_tree = t;
}
static struct commit *make_virtual_commit(struct repository *repo,
struct tree *tree,
const char *comment)
{
struct commit *commit = alloc_commit_node(repo);
set_merge_remote_desc(commit, comment, (struct object *)commit);
set_commit_tree(commit, tree);
commit->object.parsed = 1;
return commit;
}
enum rename_type {
RENAME_NORMAL = 0,
RENAME_VIA_DIR,
RENAME_ADD,
RENAME_DELETE,
RENAME_ONE_FILE_TO_ONE,
RENAME_ONE_FILE_TO_TWO,
RENAME_TWO_FILES_TO_ONE
};
/*
* Since we want to write the index eventually, we cannot reuse the index
* for these (temporary) data.
*/
struct stage_data {
struct diff_filespec stages[4]; /* mostly for oid & mode; maybe path */
struct rename_conflict_info *rename_conflict_info;
unsigned processed:1;
};
struct rename {
unsigned processed:1;
struct diff_filepair *pair;
const char *branch; /* branch that the rename occurred on */
/*
* If directory rename detection affected this rename, what was its
* original type ('A' or 'R') and it's original destination before
* the directory rename (otherwise, '\0' and NULL for these two vars).
*/
char dir_rename_original_type;
char *dir_rename_original_dest;
/*
* Purpose of src_entry and dst_entry:
*
* If 'before' is renamed to 'after' then src_entry will contain
* the versions of 'before' from the merge_base, HEAD, and MERGE in
* stages 1, 2, and 3; dst_entry will contain the respective
* versions of 'after' in corresponding locations. Thus, we have a
* total of six modes and oids, though some will be null. (Stage 0
* is ignored; we're interested in handling conflicts.)
*
* Since we don't turn on break-rewrites by default, neither
* src_entry nor dst_entry can have all three of their stages have
* non-null oids, meaning at most four of the six will be non-null.
* Also, since this is a rename, both src_entry and dst_entry will
* have at least one non-null oid, meaning at least two will be
* non-null. Of the six oids, a typical rename will have three be
* non-null. Only two implies a rename/delete, and four implies a
* rename/add.
*/
struct stage_data *src_entry;
struct stage_data *dst_entry;
};
struct rename_conflict_info {
enum rename_type rename_type;
struct rename *ren1;
struct rename *ren2;
};
static inline void setup_rename_conflict_info(enum rename_type rename_type,
struct merge_options *opt,
struct rename *ren1,
struct rename *ren2)
{
struct rename_conflict_info *ci;
/*
* When we have two renames involved, it's easiest to get the
* correct things into stage 2 and 3, and to make sure that the
* content merge puts HEAD before the other branch if we just
* ensure that branch1 == opt->branch1. So, simply flip arguments
* around if we don't have that.
*/
if (ren2 && ren1->branch != opt->branch1) {
setup_rename_conflict_info(rename_type, opt, ren2, ren1);
return;
}
CALLOC_ARRAY(ci, 1);
ci->rename_type = rename_type;
ci->ren1 = ren1;
ci->ren2 = ren2;
ci->ren1->dst_entry->processed = 0;
ci->ren1->dst_entry->rename_conflict_info = ci;
if (ren2) {
ci->ren2->dst_entry->rename_conflict_info = ci;
}
}
static int show(struct merge_options *opt, int v)
{
return (!opt->priv->call_depth && opt->verbosity >= v) ||
opt->verbosity >= 5;
}
__attribute__((format (printf, 3, 4)))
static void output(struct merge_options *opt, int v, const char *fmt, ...)
{
va_list ap;
if (!show(opt, v))
return;
strbuf_addchars(&opt->obuf, ' ', opt->priv->call_depth * 2);
va_start(ap, fmt);
strbuf_vaddf(&opt->obuf, fmt, ap);
va_end(ap);
strbuf_addch(&opt->obuf, '\n');
if (!opt->buffer_output)
flush_output(opt);
}
static void repo_output_commit_title(struct merge_options *opt,
struct repository *repo,
struct commit *commit)
{
struct merge_remote_desc *desc;
strbuf_addchars(&opt->obuf, ' ', opt->priv->call_depth * 2);
desc = merge_remote_util(commit);
if (desc)
strbuf_addf(&opt->obuf, "virtual %s\n", desc->name);
else {
strbuf_repo_add_unique_abbrev(&opt->obuf, repo,
&commit->object.oid,
DEFAULT_ABBREV);
strbuf_addch(&opt->obuf, ' ');
if (repo_parse_commit(repo, commit) != 0)
strbuf_addstr(&opt->obuf, _("(bad commit)\n"));
else {
const char *title;
const char *msg = repo_get_commit_buffer(repo, commit, NULL);
int len = find_commit_subject(msg, &title);
if (len)
strbuf_addf(&opt->obuf, "%.*s\n", len, title);
repo_unuse_commit_buffer(repo, commit, msg);
}
}
flush_output(opt);
}
static void output_commit_title(struct merge_options *opt, struct commit *commit)
{
repo_output_commit_title(opt, the_repository, commit);
}
static int add_cacheinfo(struct merge_options *opt,
const struct diff_filespec *blob,
const char *path, int stage, int refresh, int options)
{
struct index_state *istate = opt->repo->index;
struct cache_entry *ce;
int ret;
ce = make_cache_entry(istate, blob->mode, &blob->oid, path, stage, 0);
if (!ce)
return err(opt, _("add_cacheinfo failed for path '%s'; merge aborting."), path);
ret = add_index_entry(istate, ce, options);
if (refresh) {
struct cache_entry *nce;
nce = refresh_cache_entry(istate, ce,
CE_MATCH_REFRESH | CE_MATCH_IGNORE_MISSING);
if (!nce)
return err(opt, _("add_cacheinfo failed to refresh for path '%s'; merge aborting."), path);
if (nce != ce)
ret = add_index_entry(istate, nce, options);
}
return ret;
}
static inline int merge_detect_rename(struct merge_options *opt)
{
return (opt->detect_renames >= 0) ? opt->detect_renames : 1;
}
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 unpack_trees_start(struct merge_options *opt,
struct tree *common,
struct tree *head,
struct tree *merge)
{
int rc;
struct tree_desc t[3];
struct index_state tmp_index = { NULL };
memset(&opt->priv->unpack_opts, 0, sizeof(opt->priv->unpack_opts));
if (opt->priv->call_depth)
opt->priv->unpack_opts.index_only = 1;
else {
opt->priv->unpack_opts.update = 1;
/* FIXME: should only do this if !overwrite_ignore */
opt->priv->unpack_opts.preserve_ignored = 0;
}
opt->priv->unpack_opts.merge = 1;
opt->priv->unpack_opts.head_idx = 2;
opt->priv->unpack_opts.fn = threeway_merge;
opt->priv->unpack_opts.src_index = opt->repo->index;
opt->priv->unpack_opts.dst_index = &tmp_index;
opt->priv->unpack_opts.aggressive = !merge_detect_rename(opt);
setup_unpack_trees_porcelain(&opt->priv->unpack_opts, "merge");
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, &opt->priv->unpack_opts);
cache_tree_free(&opt->repo->index->cache_tree);
/*
* Update opt->repo->index to match the new results, AFTER saving a
* copy in opt->priv->orig_index. Update src_index to point to the
* saved copy. (verify_uptodate() checks src_index, and the original
* index is the one that had the necessary modification timestamps.)
*/
opt->priv->orig_index = *opt->repo->index;
*opt->repo->index = tmp_index;
opt->priv->unpack_opts.src_index = &opt->priv->orig_index;
return rc;
}
static void unpack_trees_finish(struct merge_options *opt)
{
discard_index(&opt->priv->orig_index);
clear_unpack_trees_porcelain(&opt->priv->unpack_opts);
}
static int save_files_dirs(const struct object_id *oid UNUSED,
struct strbuf *base, const char *path,
unsigned int mode, void *context)
{
struct path_hashmap_entry *entry;
int baselen = base->len;
struct merge_options *opt = context;
strbuf_addstr(base, path);
FLEX_ALLOC_MEM(entry, path, base->buf, base->len);
hashmap_entry_init(&entry->e, fspathhash(entry->path));
hashmap_add(&opt->priv->current_file_dir_set, &entry->e);
strbuf_setlen(base, baselen);
return (S_ISDIR(mode) ? READ_TREE_RECURSIVE : 0);
}
static void get_files_dirs(struct merge_options *opt, struct tree *tree)
{
struct pathspec match_all;
memset(&match_all, 0, sizeof(match_all));
read_tree(opt->repo, tree,
&match_all, save_files_dirs, opt);
}
static int get_tree_entry_if_blob(struct repository *r,
const struct object_id *tree,
const char *path,
struct diff_filespec *dfs)
{
int ret;
ret = get_tree_entry(r, tree, path, &dfs->oid, &dfs->mode);
if (S_ISDIR(dfs->mode)) {
oidcpy(&dfs->oid, null_oid());
dfs->mode = 0;
}
return ret;
}
/*
* 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(struct repository *r,
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_if_blob(r, &o->object.oid, path, &e->stages[1]);
get_tree_entry_if_blob(r, &a->object.oid, path, &e->stages[2]);
get_tree_entry_if_blob(r, &b->object.oid, path, &e->stages[3]);
item = string_list_insert(entries, path);
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(struct index_state *istate)
{
struct string_list *unmerged = xmalloc(sizeof(struct string_list));
int i;
string_list_init_dup(unmerged);
/* TODO: audit for interaction with sparse-index. */
ensure_full_index(istate);
for (i = 0; i < istate->cache_nr; i++) {
struct string_list_item *item;
struct stage_data *e;
const struct cache_entry *ce = istate->cache[i];
if (!ce_stage(ce))
continue;
item = string_list_lookup(unmerged, ce->name);
if (!item) {
item = string_list_insert(unmerged, ce->name);
item->util = xcalloc(1, sizeof(struct stage_data));
}
e = item->util;
e->stages[ce_stage(ce)].mode = ce->ce_mode;
oidcpy(&e->stages[ce_stage(ce)].oid, &ce->oid);
}
return unmerged;
}
static int string_list_df_name_compare(const char *one, const char *two)
{
int onelen = strlen(one);
int twolen = strlen(two);
/*
* Here we only care that entries for D/F conflicts are
* adjacent, in particular with the file of the D/F conflict
* appearing before files below the corresponding directory.
* The order of the rest of the list is irrelevant for us.
*
* To achieve this, we sort with df_name_compare and provide
* the mode S_IFDIR so that D/F conflicts will sort correctly.
* We use the mode S_IFDIR for everything else for simplicity,
* since in other cases any changes in their order due to
* sorting cause no problems for us.
*/
int cmp = df_name_compare(one, onelen, S_IFDIR,
two, twolen, S_IFDIR);
/*
* Now that 'foo' and 'foo/bar' compare equal, we have to make sure
* that 'foo' comes before 'foo/bar'.
*/
if (cmp)
return cmp;
return onelen - twolen;
}
static void record_df_conflict_files(struct merge_options *opt,
struct string_list *entries)
{
/* If there is a D/F conflict and the file for such a conflict
* currently exists in the working tree, we want to allow it to be
* removed to make room for the corresponding directory if needed.
* The files underneath the directories of such D/F conflicts will
* be processed before the corresponding file involved in the D/F
* conflict. If the D/F directory ends up being removed by the
* merge, then we won't have to touch the D/F file. If the D/F
* directory needs to be written to the working copy, then the D/F
* file will simply be removed (in make_room_for_path()) to make
* room for the necessary paths. Note that if both the directory
* and the file need to be present, then the D/F file will be
* reinstated with a new unique name at the time it is processed.
*/
struct string_list df_sorted_entries = STRING_LIST_INIT_NODUP;
const char *last_file = NULL;
int last_len = 0;
int i;
/*
* If we're merging merge-bases, we don't want to bother with
* any working directory changes.
*/
if (opt->priv->call_depth)
return;
/* Ensure D/F conflicts are adjacent in the entries list. */
for (i = 0; i < entries->nr; i++) {
struct string_list_item *next = &entries->items[i];
string_list_append(&df_sorted_entries, next->string)->util =
next->util;
}
df_sorted_entries.cmp = string_list_df_name_compare;
string_list_sort(&df_sorted_entries);
string_list_clear(&opt->priv->df_conflict_file_set, 1);
for (i = 0; i < df_sorted_entries.nr; i++) {
const char *path = df_sorted_entries.items[i].string;
int len = strlen(path);
struct stage_data *e = df_sorted_entries.items[i].util;
/*
* Check if last_file & path correspond to a D/F conflict;
* i.e. whether path is last_file+'/'+<something>.
* If so, record that it's okay to remove last_file to make
* room for path and friends if needed.
*/
if (last_file &&
len > last_len &&
memcmp(path, last_file, last_len) == 0 &&
path[last_len] == '/') {
string_list_insert(&opt->priv->df_conflict_file_set, last_file);
}
/*
* Determine whether path could exist as a file in the
* working directory as a possible D/F conflict. This
* will only occur when it exists in stage 2 as a
* file.
*/
if (S_ISREG(e->stages[2].mode) || S_ISLNK(e->stages[2].mode)) {
last_file = path;
last_len = len;
} else {
last_file = NULL;
}
}
string_list_clear(&df_sorted_entries, 0);
}
static int update_stages(struct merge_options *opt, const char *path,
const struct diff_filespec *o,
const struct diff_filespec *a,
const struct diff_filespec *b)
{
/*
* NOTE: It is usually a bad idea to call update_stages on a path
* before calling update_file on that same path, since it can
* sometimes lead to spurious "refusing to lose untracked file..."
* messages from update_file (via make_room_for path via
* would_lose_untracked). Instead, reverse the order of the calls
* (executing update_file first and then update_stages).
*/
int clear = 1;
int options = ADD_CACHE_OK_TO_ADD | ADD_CACHE_SKIP_DFCHECK;
if (clear)
if (remove_file_from_index(opt->repo->index, path))
return -1;
if (o)
if (add_cacheinfo(opt, o, path, 1, 0, options))
return -1;
if (a)
if (add_cacheinfo(opt, a, path, 2, 0, options))
return -1;
if (b)
if (add_cacheinfo(opt, b, path, 3, 0, options))
return -1;
return 0;
}
static void update_entry(struct stage_data *entry,
struct diff_filespec *o,
struct diff_filespec *a,
struct diff_filespec *b)
{
entry->processed = 0;
entry->stages[1].mode = o->mode;
entry->stages[2].mode = a->mode;
entry->stages[3].mode = b->mode;
oidcpy(&entry->stages[1].oid, &o->oid);
oidcpy(&entry->stages[2].oid, &a->oid);
oidcpy(&entry->stages[3].oid, &b->oid);
}
static int remove_file(struct merge_options *opt, int clean,
const char *path, int no_wd)
{
int update_cache = opt->priv->call_depth || clean;
int update_working_directory = !opt->priv->call_depth && !no_wd;
if (update_cache) {
if (remove_file_from_index(opt->repo->index, path))
return -1;
}
if (update_working_directory) {
if (ignore_case) {
struct cache_entry *ce;
ce = index_file_exists(opt->repo->index, path, strlen(path),
ignore_case);
if (ce && ce_stage(ce) == 0 && strcmp(path, ce->name))
return 0;
}
if (remove_path(path))
return -1;
}
return 0;
}
/* add a string to a strbuf, but converting "/" to "_" */
static void add_flattened_path(struct strbuf *out, const char *s)
{
size_t i = out->len;
strbuf_addstr(out, s);
for (; i < out->len; i++)
if (out->buf[i] == '/')
out->buf[i] = '_';
}
static char *unique_path(struct merge_options *opt,
const char *path,
const char *branch)
{
struct path_hashmap_entry *entry;
struct strbuf newpath = STRBUF_INIT;
int suffix = 0;
size_t base_len;
strbuf_addf(&newpath, "%s~", path);
add_flattened_path(&newpath, branch);
base_len = newpath.len;
while (hashmap_get_from_hash(&opt->priv->current_file_dir_set,
fspathhash(newpath.buf), newpath.buf) ||
(!opt->priv->call_depth && file_exists(newpath.buf))) {
strbuf_setlen(&newpath, base_len);
strbuf_addf(&newpath, "_%d", suffix++);
}
FLEX_ALLOC_MEM(entry, path, newpath.buf, newpath.len);
hashmap_entry_init(&entry->e, fspathhash(entry->path));
hashmap_add(&opt->priv->current_file_dir_set, &entry->e);
return strbuf_detach(&newpath, NULL);
}
/**
* Check whether a directory in the index is in the way of an incoming
* file. Return 1 if so. If check_working_copy is non-zero, also
* check the working directory. If empty_ok is non-zero, also return
* 0 in the case where the working-tree dir exists but is empty.
*/
static int dir_in_way(struct index_state *istate, const char *path,
int check_working_copy, int empty_ok)
{
int pos;
struct strbuf dirpath = STRBUF_INIT;
struct stat st;
strbuf_addstr(&dirpath, path);
strbuf_addch(&dirpath, '/');
pos = index_name_pos(istate, dirpath.buf, dirpath.len);
if (pos < 0)
pos = -1 - pos;
if (pos < istate->cache_nr &&
!strncmp(dirpath.buf, istate->cache[pos]->name, dirpath.len)) {
strbuf_release(&dirpath);
return 1;
}
strbuf_release(&dirpath);
return check_working_copy && !lstat(path, &st) && S_ISDIR(st.st_mode) &&
!(empty_ok && is_empty_dir(path)) &&
!has_symlink_leading_path(path, strlen(path));
}
/*
* Returns whether path was tracked in the index before the merge started,
* and its oid and mode match the specified values
*/
static int was_tracked_and_matches(struct merge_options *opt, const char *path,
const struct diff_filespec *blob)
{
int pos = index_name_pos(&opt->priv->orig_index, path, strlen(path));
struct cache_entry *ce;
if (0 > pos)
/* we were not tracking this path before the merge */
return 0;
/* See if the file we were tracking before matches */
ce = opt->priv->orig_index.cache[pos];
return (oideq(&ce->oid, &blob->oid) && ce->ce_mode == blob->mode);
}
/*
* Returns whether path was tracked in the index before the merge started
*/
static int was_tracked(struct merge_options *opt, const char *path)
{
int pos = index_name_pos(&opt->priv->orig_index, path, strlen(path));
if (0 <= pos)
/* we were tracking this path before the merge */
return 1;
return 0;
}
static int would_lose_untracked(struct merge_options *opt, const char *path)
{
struct index_state *istate = opt->repo->index;
/*
* This may look like it can be simplified to:
* return !was_tracked(opt, path) && file_exists(path)
* but it can't. This function needs to know whether path was in
* the working tree due to EITHER having been tracked in the index
* before the merge OR having been put into the working copy and
* index by unpack_trees(). Due to that either-or requirement, we
* check the current index instead of the original one.
*
* Note that we do not need to worry about merge-recursive itself
* updating the index after unpack_trees() and before calling this
* function, because we strictly require all code paths in
* merge-recursive to update the working tree first and the index
* second. Doing otherwise would break
* update_file()/would_lose_untracked(); see every comment in this
* file which mentions "update_stages".
*/
int pos = index_name_pos(istate, path, strlen(path));
if (pos < 0)
pos = -1 - pos;
while (pos < istate->cache_nr &&
!strcmp(path, istate->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(istate->cache[pos])) {
case 0:
case 2:
return 0;
}
pos++;
}
return file_exists(path);
}
static int was_dirty(struct merge_options *opt, const char *path)
{
struct cache_entry *ce;
int dirty = 1;
if (opt->priv->call_depth || !was_tracked(opt, path))
return !dirty;
ce = index_file_exists(opt->priv->unpack_opts.src_index,
path, strlen(path), ignore_case);
dirty = verify_uptodate(ce, &opt->priv->unpack_opts) != 0;
return dirty;
}
static int make_room_for_path(struct merge_options *opt, const char *path)
{
int status, i;
const char *msg = _("failed to create path '%s'%s");
/* Unlink any D/F conflict files that are in the way */
for (i = 0; i < opt->priv->df_conflict_file_set.nr; i++) {
const char *df_path = opt->priv->df_conflict_file_set.items[i].string;
size_t pathlen = strlen(path);
size_t df_pathlen = strlen(df_path);
if (df_pathlen < pathlen &&
path[df_pathlen] == '/' &&
strncmp(path, df_path, df_pathlen) == 0) {
output(opt, 3,
_("Removing %s to make room for subdirectory\n"),
df_path);
unlink(df_path);
unsorted_string_list_delete_item(&opt->priv->df_conflict_file_set,
i, 0);
break;
}
}
/* Make sure leading directories are created */
status = safe_create_leading_directories_const(path);
if (status) {
if (status == SCLD_EXISTS)
/* something else exists */
return err(opt, msg, path, _(": perhaps a D/F conflict?"));
return err(opt, msg, path, "");
}
/*
* Do not unlink a file in the work tree if we are not
* tracking it.
*/
if (would_lose_untracked(opt, path))
return err(opt, _("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 err(opt, msg, path, _(": perhaps a D/F conflict?"));
}
static int update_file_flags(struct merge_options *opt,
const struct diff_filespec *contents,
const char *path,
int update_cache,
int update_wd)
{
int ret = 0;
if (opt->priv->call_depth)
update_wd = 0;
if (update_wd) {
enum object_type type;
void *buf;
unsigned long size;
if (S_ISGITLINK(contents->mode)) {
/*
* 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.
*/
update_wd = 0;
goto update_index;
}
buf = read_object_file(&contents->oid, &type, &size);
if (!buf) {
ret = err(opt, _("cannot read object %s '%s'"),
oid_to_hex(&contents->oid), path);
goto free_buf;
}
if (type != OBJ_BLOB) {
ret = err(opt, _("blob expected for %s '%s'"),
oid_to_hex(&contents->oid), path);
goto free_buf;
}
if (S_ISREG(contents->mode)) {
struct strbuf strbuf = STRBUF_INIT;
if (convert_to_working_tree(opt->repo->index,
path, buf, size, &strbuf, NULL)) {
free(buf);
size = strbuf.len;
buf = strbuf_detach(&strbuf, NULL);
}
}
if (make_room_for_path(opt, path) < 0) {
update_wd = 0;
goto free_buf;
}
if (S_ISREG(contents->mode) ||
(!has_symlinks && S_ISLNK(contents->mode))) {
int fd;
int mode = (contents->mode & 0100 ? 0777 : 0666);
fd = open(path, O_WRONLY | O_TRUNC | O_CREAT, mode);
if (fd < 0) {
ret = err(opt, _("failed to open '%s': %s"),
path, strerror(errno));
goto free_buf;
}
write_in_full(fd, buf, size);
close(fd);
} else if (S_ISLNK(contents->mode)) {
char *lnk = xmemdupz(buf, size);
safe_create_leading_directories_const(path);
unlink(path);
if (symlink(lnk, path))
ret = err(opt, _("failed to symlink '%s': %s"),
path, strerror(errno));
free(lnk);
} else
ret = err(opt,
_("do not know what to do with %06o %s '%s'"),
contents->mode, oid_to_hex(&contents->oid), path);
free_buf:
free(buf);
}
update_index:
if (!ret && update_cache) {
int refresh = (!opt->priv->call_depth &&
contents->mode != S_IFGITLINK);
if (add_cacheinfo(opt, contents, path, 0, refresh,
ADD_CACHE_OK_TO_ADD))
return -1;
}
return ret;
}
static int update_file(struct merge_options *opt,
int clean,
const struct diff_filespec *contents,
const char *path)
{
return update_file_flags(opt, contents, path,
opt->priv->call_depth || clean, !opt->priv->call_depth);
}
/* Low level file merging, update and removal */
struct merge_file_info {
struct diff_filespec blob; /* mostly use oid & mode; sometimes path */
unsigned clean:1,
merge:1;
};
static int merge_3way(struct merge_options *opt,
mmbuffer_t *result_buf,
const struct diff_filespec *o,
const struct diff_filespec *a,
const struct diff_filespec *b,
const char *branch1,
const char *branch2,
const int extra_marker_size)
{
mmfile_t orig, src1, src2;
struct ll_merge_options ll_opts = {0};
char *base, *name1, *name2;
enum ll_merge_result merge_status;
ll_opts.renormalize = opt->renormalize;
ll_opts.extra_marker_size = extra_marker_size;
ll_opts.xdl_opts = opt->xdl_opts;
if (opt->priv->call_depth) {
ll_opts.virtual_ancestor = 1;
ll_opts.variant = 0;
} else {
switch (opt->recursive_variant) {
case MERGE_VARIANT_OURS:
ll_opts.variant = XDL_MERGE_FAVOR_OURS;
break;
case MERGE_VARIANT_THEIRS:
ll_opts.variant = XDL_MERGE_FAVOR_THEIRS;
break;
default:
ll_opts.variant = 0;
break;
}
}
assert(a->path && b->path && o->path && opt->ancestor);
if (strcmp(a->path, b->path) || strcmp(a->path, o->path) != 0) {
base = mkpathdup("%s:%s", opt->ancestor, o->path);
name1 = mkpathdup("%s:%s", branch1, a->path);
name2 = mkpathdup("%s:%s", branch2, b->path);
} else {
base = mkpathdup("%s", opt->ancestor);
name1 = mkpathdup("%s", branch1);
name2 = mkpathdup("%s", branch2);
}
read_mmblob(&orig, &o->oid);
read_mmblob(&src1, &a->oid);
read_mmblob(&src2, &b->oid);
/*
* FIXME: Using a->path for normalization rules in ll_merge could be
* wrong if we renamed from a->path to b->path. We should use the
* target path for where the file will be written.
*/
merge_status = ll_merge(result_buf, a->path, &orig, base,
&src1, name1, &src2, name2,
opt->repo->index, &ll_opts);
if (merge_status == LL_MERGE_BINARY_CONFLICT)
warning("Cannot merge binary files: %s (%s vs. %s)",
a->path, name1, name2);
free(base);
free(name1);
free(name2);
free(orig.ptr);
free(src1.ptr);
free(src2.ptr);
return merge_status;
}
static int find_first_merges(struct repository *repo,
struct object_array *result, const char *path,
struct commit *a, struct commit *b)
{
int i, j;
struct object_array merges = OBJECT_ARRAY_INIT;
struct commit *commit;
int contains_another;
char merged_revision[GIT_MAX_HEXSZ + 2];
const char *rev_args[] = { "rev-list", "--merges", "--ancestry-path",
"--all", merged_revision, NULL };
struct rev_info revs;
struct setup_revision_opt rev_opts;
memset(result, 0, sizeof(struct object_array));
memset(&rev_opts, 0, sizeof(rev_opts));
/* get all revisions that merge commit a */
xsnprintf(merged_revision, sizeof(merged_revision), "^%s",
oid_to_hex(&a->object.oid));
repo_init_revisions(repo, &revs, NULL);
/* FIXME: can't handle linked worktrees in submodules yet */
revs.single_worktree = path != NULL;
setup_revisions(ARRAY_SIZE(rev_args)-1, rev_args, &revs, &rev_opts);
/* save all revisions from the above list that contain b */
if (prepare_revision_walk(&revs))
die("revision walk setup failed");
while ((commit = get_revision(&revs)) != NULL) {
struct object *o = &(commit->object);
if (repo_in_merge_bases(repo, b, commit))
add_object_array(o, NULL, &merges);
}
reset_revision_walk();
/* Now we've got all merges that contain a and b. Prune all
* merges that contain another found merge and save them in
* result.
*/
for (i = 0; i < merges.nr; i++) {
struct commit *m1 = (struct commit *) merges.objects[i].item;
contains_another = 0;
for (j = 0; j < merges.nr; j++) {
struct commit *m2 = (struct commit *) merges.objects[j].item;
if (i != j && repo_in_merge_bases(repo, m2, m1)) {
contains_another = 1;
break;
}
}
if (!contains_another)
add_object_array(merges.objects[i].item, NULL, result);
}
object_array_clear(&merges);
release_revisions(&revs);
return result->nr;
}
static void print_commit(struct repository *repo, struct commit *commit)
{
struct strbuf sb = STRBUF_INIT;
struct pretty_print_context ctx = {0};
ctx.date_mode.type = DATE_NORMAL;
/* FIXME: Merge this with output_commit_title() */
assert(!merge_remote_util(commit));
repo_format_commit_message(repo, commit, " %h: %m %s", &sb, &ctx);
fprintf(stderr, "%s\n", sb.buf);
strbuf_release(&sb);
}
static int is_valid(const struct diff_filespec *dfs)
{
return dfs->mode != 0 && !is_null_oid(&dfs->oid);
}
static int merge_submodule(struct merge_options *opt,
struct object_id *result, const char *path,
const struct object_id *base, const struct object_id *a,
const struct object_id *b)
{
struct repository subrepo;
int ret = 0;
struct commit *commit_base, *commit_a, *commit_b;
int parent_count;
struct object_array merges;
int i;
int search = !opt->priv->call_depth;
/* store a in result in case we fail */
/* FIXME: This is the WRONG resolution for the recursive case when
* we need to be careful to avoid accidentally matching either side.
* Should probably use o instead there, much like we do for merging
* binaries.
*/
oidcpy(result, a);
/* we can not handle deletion conflicts */
if (is_null_oid(base))
return 0;
if (is_null_oid(a))
return 0;
if (is_null_oid(b))
return 0;
if (repo_submodule_init(&subrepo, opt->repo, path, null_oid())) {
output(opt, 1, _("Failed to merge submodule %s (not checked out)"), path);
return 0;
}
if (!(commit_base = lookup_commit_reference(&subrepo, base)) ||
!(commit_a = lookup_commit_reference(&subrepo, a)) ||
!(commit_b = lookup_commit_reference(&subrepo, b))) {
output(opt, 1, _("Failed to merge submodule %s (commits not present)"), path);
goto cleanup;
}
/* check whether both changes are forward */
if (!repo_in_merge_bases(&subrepo, commit_base, commit_a) ||
!repo_in_merge_bases(&subrepo, commit_base, commit_b)) {
output(opt, 1, _("Failed to merge submodule %s (commits don't follow merge-base)"), path);
goto cleanup;
}
/* Case #1: a is contained in b or vice versa */
if (repo_in_merge_bases(&subrepo, commit_a, commit_b)) {
oidcpy(result, b);
if (show(opt, 3)) {
output(opt, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
repo_output_commit_title(opt, &subrepo, commit_b);
} else if (show(opt, 2))
output(opt, 2, _("Fast-forwarding submodule %s"), path);
else
; /* no output */
ret = 1;
goto cleanup;
}
if (repo_in_merge_bases(&subrepo, commit_b, commit_a)) {
oidcpy(result, a);
if (show(opt, 3)) {
output(opt, 3, _("Fast-forwarding submodule %s to the following commit:"), path);
repo_output_commit_title(opt, &subrepo, commit_a);
} else if (show(opt, 2))
output(opt, 2, _("Fast-forwarding submodule %s"), path);
else
; /* no output */
ret = 1;
goto cleanup;
}
/*
* Case #2: There are one or more merges that contain a and b in
* the submodule. If there is only one, then present it as a
* suggestion to the user, but leave it marked unmerged so the
* user needs to confirm the resolution.
*/
/* Skip the search if makes no sense to the calling context. */
if (!search)
goto cleanup;
/* find commit which merges them */
parent_count = find_first_merges(&subrepo, &merges, path,
commit_a, commit_b);
switch (parent_count) {
case 0:
output(opt, 1, _("Failed to merge submodule %s (merge following commits not found)"), path);
break;
case 1:
output(opt, 1, _("Failed to merge submodule %s (not fast-forward)"), path);
output(opt, 2, _("Found a possible merge resolution for the submodule:\n"));
print_commit(&subrepo, (struct commit *) merges.objects[0].item);
output(opt, 2, _(
"If this is correct simply add it to the index "
"for example\n"
"by using:\n\n"
" git update-index --cacheinfo 160000 %s \"%s\"\n\n"
"which will accept this suggestion.\n"),
oid_to_hex(&merges.objects[0].item->oid), path);
break;
default:
output(opt, 1, _("Failed to merge submodule %s (multiple merges found)"), path);
for (i = 0; i < merges.nr; i++)
print_commit(&subrepo, (struct commit *) merges.objects[i].item);
}
object_array_clear(&merges);
cleanup:
repo_clear(&subrepo);
return ret;
}
static int merge_mode_and_contents(struct merge_options *opt,
const struct diff_filespec *o,
const struct diff_filespec *a,
const struct diff_filespec *b,
const char *filename,
const char *branch1,
const char *branch2,
const int extra_marker_size,
struct merge_file_info *result)
{
if (opt->branch1 != branch1) {
/*
* It's weird getting a reverse merge with HEAD on the bottom
* side of the conflict markers and the other branch on the
* top. Fix that.
*/
return merge_mode_and_contents(opt, o, b, a,
filename,
branch2, branch1,
extra_marker_size, result);
}
result->merge = 0;
result->clean = 1;
if ((S_IFMT & a->mode) != (S_IFMT & b->mode)) {
result->clean = 0;
/*
* FIXME: This is a bad resolution for recursive case; for
* the recursive case we want something that is unlikely to
* accidentally match either side. Also, while it makes
* sense to prefer regular files over symlinks, it doesn't
* make sense to prefer regular files over submodules.
*/
if (S_ISREG(a->mode)) {
result->blob.mode = a->mode;
oidcpy(&result->blob.oid, &a->oid);
} else {
result->blob.mode = b->mode;
oidcpy(&result->blob.oid, &b->oid);
}
} else {
if (!oideq(&a->oid, &o->oid) && !oideq(&b->oid, &o->oid))
result->merge = 1;
/*
* Merge modes
*/
if (a->mode == b->mode || a->mode == o->mode)
result->blob.mode = b->mode;
else {
result->blob.mode = a->mode;
if (b->mode != o->mode) {
result->clean = 0;
result->merge = 1;
}
}
if (oideq(&a->oid, &b->oid) || oideq(&a->oid, &o->oid))
oidcpy(&result->blob.oid, &b->oid);
else if (oideq(&b->oid, &o->oid))
oidcpy(&result->blob.oid, &a->oid);
else if (S_ISREG(a->mode)) {
mmbuffer_t result_buf;
int ret = 0, merge_status;
merge_status = merge_3way(opt, &result_buf, o, a, b,
branch1, branch2,
extra_marker_size);
if ((merge_status < 0) || !result_buf.ptr)
ret = err(opt, _("Failed to execute internal merge"));
if (!ret &&
write_object_file(result_buf.ptr, result_buf.size,
OBJ_BLOB, &result->blob.oid))
ret = err(opt, _("Unable to add %s to database"),
a->path);
free(result_buf.ptr);
if (ret)
return ret;
/* FIXME: bug, what if modes didn't match? */
result->clean = (merge_status == 0);
} else if (S_ISGITLINK(a->mode)) {
result->clean = merge_submodule(opt, &result->blob.oid,
o->path,
&o->oid,
&a->oid,
&b->oid);
} else if (S_ISLNK(a->mode)) {
switch (opt->recursive_variant) {
case MERGE_VARIANT_NORMAL:
oidcpy(&result->blob.oid, &a->oid);
if (!oideq(&a->oid, &b->oid))
result->clean = 0;
break;
case MERGE_VARIANT_OURS:
oidcpy(&result->blob.oid, &a->oid);
break;
case MERGE_VARIANT_THEIRS:
oidcpy(&result->blob.oid, &b->oid);
break;
}
} else
BUG("unsupported object type in the tree");
}
if (result->merge)
output(opt, 2, _("Auto-merging %s"), filename);
return 0;
}
static int handle_rename_via_dir(struct merge_options *opt,
struct rename_conflict_info *ci)
{
/*
* Handle file adds that need to be renamed due to directory rename
* detection. This differs from handle_rename_normal, because
* there is no content merge to do; just move the file into the
* desired final location.
*/
const struct rename *ren = ci->ren1;
const struct diff_filespec *dest = ren->pair->two;
char *file_path = dest->path;
int mark_conflicted = (opt->detect_directory_renames ==
MERGE_DIRECTORY_RENAMES_CONFLICT);
assert(ren->dir_rename_original_dest);
if (!opt->priv->call_depth && would_lose_untracked(opt, dest->path)) {
mark_conflicted = 1;
file_path = unique_path(opt, dest->path, ren->branch);
output(opt, 1, _("Error: Refusing to lose untracked file at %s; "
"writing to %s instead."),
dest->path, file_path);
}
if (mark_conflicted) {
/*
* Write the file in worktree at file_path. In the index,
* only record the file at dest->path in the appropriate
* higher stage.
*/
if (update_file(opt, 0, dest, file_path))
return -1;
if (file_path != dest->path)
free(file_path);
if (update_stages(opt, dest->path, NULL,
ren->branch == opt->branch1 ? dest : NULL,
ren->branch == opt->branch1 ? NULL : dest))
return -1;
return 0; /* not clean, but conflicted */
} else {
/* Update dest->path both in index and in worktree */
if (update_file(opt, 1, dest, dest->path))
return -1;
return 1; /* clean */
}
}
static int handle_change_delete(struct merge_options *opt,
const char *path, const char *old_path,
const struct diff_filespec *o,
const struct diff_filespec *changed,
const char *change_branch,
const char *delete_branch,
const char *change, const char *change_past)
{
char *alt_path = NULL;
const char *update_path = path;
int ret = 0;
if (dir_in_way(opt->repo->index, path, !opt->priv->call_depth, 0) ||
(!opt->priv->call_depth && would_lose_untracked(opt, path))) {
update_path = alt_path = unique_path(opt, path, change_branch);
}
if (opt->priv->call_depth) {
/*
* We cannot arbitrarily accept either a_sha or b_sha as
* correct; since there is no true "middle point" between
* them, simply reuse the base version for virtual merge base.
*/
ret = remove_file_from_index(opt->repo->index, path);
if (!ret)
ret = update_file(opt, 0, o, update_path);
} else {
/*
* Despite the four nearly duplicate messages and argument
* lists below and the ugliness of the nested if-statements,
* having complete messages makes the job easier for
* translators.
*
* The slight variance among the cases is due to the fact
* that:
* 1) directory/file conflicts (in effect if
* !alt_path) could cause us to need to write the
* file to a different path.
* 2) renames (in effect if !old_path) could mean that
* there are two names for the path that the user
* may know the file by.
*/
if (!alt_path) {
if (!old_path) {
output(opt, 1, _("CONFLICT (%s/delete): %s deleted in %s "
"and %s in %s. Version %s of %s left in tree."),
change, path, delete_branch, change_past,
change_branch, change_branch, path);
} else {
output(opt, 1, _("CONFLICT (%s/delete): %s deleted in %s "
"and %s to %s in %s. Version %s of %s left in tree."),
change, old_path, delete_branch, change_past, path,
change_branch, change_branch, path);
}
} else {
if (!old_path) {
output(opt, 1, _("CONFLICT (%s/delete): %s deleted in %s "
"and %s in %s. Version %s of %s left in tree at %s."),
change, path, delete_branch, change_past,
change_branch, change_branch, path, alt_path);
} else {
output(opt, 1, _("CONFLICT (%s/delete): %s deleted in %s "
"and %s to %s in %s. Version %s of %s left in tree at %s."),
change, old_path, delete_branch, change_past, path,
change_branch, change_branch, path, alt_path);
}
}
/*
* No need to call update_file() on path when change_branch ==
* opt->branch1 && !alt_path, since that would needlessly touch
* path. We could call update_file_flags() with update_cache=0
* and update_wd=0, but that's a no-op.
*/
if (change_branch != opt->branch1 || alt_path)
ret = update_file(opt, 0, changed, update_path);
}
free(alt_path);
return ret;
}
static int handle_rename_delete(struct merge_options *opt,
struct rename_conflict_info *ci)
{
const struct rename *ren = ci->ren1;
const struct diff_filespec *orig = ren->pair->one;
const struct diff_filespec *dest = ren->pair->two;
const char *rename_branch = ren->branch;
const char *delete_branch = (opt->branch1 == ren->branch ?
opt->branch2 : opt->branch1);
if (handle_change_delete(opt,
opt->priv->call_depth ? orig->path : dest->path,
opt->priv->call_depth ? NULL : orig->path,
orig, dest,
rename_branch, delete_branch,
_("rename"), _("renamed")))
return -1;
if (opt->priv->call_depth)
return remove_file_from_index(opt->repo->index, dest->path);
else
return update_stages(opt, dest->path, NULL,
rename_branch == opt->branch1 ? dest : NULL,
rename_branch == opt->branch1 ? NULL : dest);
}
static int handle_file_collision(struct merge_options *opt,
const char *collide_path,
const char *prev_path1,
const char *prev_path2,
const char *branch1, const char *branch2,
struct diff_filespec *a,
struct diff_filespec *b)
{
struct merge_file_info mfi;
struct diff_filespec null;
char *alt_path = NULL;
const char *update_path = collide_path;
/*
* It's easiest to get the correct things into stage 2 and 3, and
* to make sure that the content merge puts HEAD before the other
* branch if we just ensure that branch1 == opt->branch1. So, simply
* flip arguments around if we don't have that.
*/
if (branch1 != opt->branch1) {
return handle_file_collision(opt, collide_path,
prev_path2, prev_path1,
branch2, branch1,
b, a);
}
/* Remove rename sources if rename/add or rename/rename(2to1) */
if (prev_path1)
remove_file(opt, 1, prev_path1,
opt->priv->call_depth || would_lose_untracked(opt, prev_path1));
if (prev_path2)
remove_file(opt, 1, prev_path2,
opt->priv->call_depth || would_lose_untracked(opt, prev_path2));
/*
* Remove the collision path, if it wouldn't cause dirty contents
* or an untracked file to get lost. We'll either overwrite with
* merged contents, or just write out to differently named files.
*/
if (was_dirty(opt, collide_path)) {
output(opt, 1, _("Refusing to lose dirty file at %s"),
collide_path);
update_path = alt_path = unique_path(opt, collide_path, "merged");
} else if (would_lose_untracked(opt, collide_path)) {
/*
* Only way we get here is if both renames were from
* a directory rename AND user had an untracked file
* at the location where both files end up after the
* two directory renames. See testcase 10d of t6043.
*/
output(opt, 1, _("Refusing to lose untracked file at "
"%s, even though it's in the way."),
collide_path);
update_path = alt_path = unique_path(opt, collide_path, "merged");
} else {
/*
* FIXME: It's possible that the two files are identical
* and that the current working copy happens to match, in
* which case we are unnecessarily touching the working
* tree file. It's not a likely enough scenario that I
* want to code up the checks for it and a better fix is
* available if we restructure how unpack_trees() and
* merge-recursive interoperate anyway, so punting for
* now...
*/
remove_file(opt, 0, collide_path, 0);
}
/* Store things in diff_filespecs for functions that need it */
null.path = (char *)collide_path;
oidcpy(&null.oid, null_oid());
null.mode = 0;
if (merge_mode_and_contents(opt, &null, a, b, collide_path,
branch1, branch2, opt->priv->call_depth * 2, &mfi))
return -1;
mfi.clean &= !alt_path;
if (update_file(opt, mfi.clean, &mfi.blob, update_path))
return -1;
if (!mfi.clean && !opt->priv->call_depth &&
update_stages(opt, collide_path, NULL, a, b))
return -1;
free(alt_path);
/*
* FIXME: If both a & b both started with conflicts (only possible
* if they came from a rename/rename(2to1)), but had IDENTICAL
* contents including those conflicts, then in the next line we claim
* it was clean. If someone cares about this case, we should have the
* caller notify us if we started with conflicts.
*/
return mfi.clean;
}
static int handle_rename_add(struct merge_options *opt,
struct rename_conflict_info *ci)
{
/* a was renamed to c, and a separate c was added. */
struct diff_filespec *a = ci->ren1->pair->one;
struct diff_filespec *c = ci->ren1->pair->two;
char *path = c->path;
char *prev_path_desc;
struct merge_file_info mfi;
const char *rename_branch = ci->ren1->branch;
const char *add_branch = (opt->branch1 == rename_branch ?
opt->branch2 : opt->branch1);
int other_stage = (ci->ren1->branch == opt->branch1 ? 3 : 2);
output(opt, 1, _("CONFLICT (rename/add): "
"Rename %s->%s in %s. Added %s in %s"),
a->path, c->path, rename_branch,
c->path, add_branch);
prev_path_desc = xstrfmt("version of %s from %s", path, a->path);
ci->ren1->src_entry->stages[other_stage].path = a->path;
if (merge_mode_and_contents(opt, a, c,
&ci->ren1->src_entry->stages[other_stage],
prev_path_desc,
opt->branch1, opt->branch2,
1 + opt->priv->call_depth * 2, &mfi))
return -1;
free(prev_path_desc);
ci->ren1->dst_entry->stages[other_stage].path = mfi.blob.path = c->path;
return handle_file_collision(opt,
c->path, a->path, NULL,
rename_branch, add_branch,
&mfi.blob,
&ci->ren1->dst_entry->stages[other_stage]);
}
static char *find_path_for_conflict(struct merge_options *opt,
const char *path,
const char *branch1,
const char *branch2)
{
char *new_path = NULL;
if (dir_in_way(opt->repo->index, path, !opt->priv->call_depth, 0)) {
new_path = unique_path(opt, path, branch1);
output(opt, 1, _("%s is a directory in %s adding "
"as %s instead"),
path, branch2, new_path);
} else if (would_lose_untracked(opt, path)) {
new_path = unique_path(opt, path, branch1);
output(opt, 1, _("Refusing to lose untracked file"
" at %s; adding as %s instead"),
path, new_path);
}
return new_path;
}
/*
* Toggle the stage number between "ours" and "theirs" (2 and 3).
*/
static inline int flip_stage(int stage)
{
return (2 + 3) - stage;
}
static int handle_rename_rename_1to2(struct merge_options *opt,
struct rename_conflict_info *ci)
{
/* One file was renamed in both branches, but to different names. */
struct merge_file_info mfi;
struct diff_filespec *add;
struct diff_filespec *o = ci->ren1->pair->one;
struct diff_filespec *a = ci->ren1->pair->two;
struct diff_filespec *b = ci->ren2->pair->two;
char *path_desc;
output(opt, 1, _("CONFLICT (rename/rename): "
"Rename \"%s\"->\"%s\" in branch \"%s\" "
"rename \"%s\"->\"%s\" in \"%s\"%s"),
o->path, a->path, ci->ren1->branch,
o->path, b->path, ci->ren2->branch,
opt->priv->call_depth ? _(" (left unresolved)") : "");
path_desc = xstrfmt("%s and %s, both renamed from %s",
a->path, b->path, o->path);
if (merge_mode_and_contents(opt, o, a, b, path_desc,
ci->ren1->branch, ci->ren2->branch,
opt->priv->call_depth * 2, &mfi))
return -1;
free(path_desc);
if (opt->priv->call_depth)
remove_file_from_index(opt->repo->index, o->path);
/*
* For each destination path, we need to see if there is a
* rename/add collision. If not, we can write the file out
* to the specified location.
*/
add = &ci->ren1->dst_entry->stages[flip_stage(2)];
if (is_valid(add)) {
add->path = mfi.blob.path = a->path;
if (handle_file_collision(opt, a->path,
NULL, NULL,
ci->ren1->branch,
ci->ren2->branch,
&mfi.blob, add) < 0)
return -1;
} else {
char *new_path = find_path_for_conflict(opt, a->path,
ci->ren1->branch,
ci->ren2->branch);
if (update_file(opt, 0, &mfi.blob,
new_path ? new_path : a->path))
return -1;
free(new_path);
if (!opt->priv->call_depth &&
update_stages(opt, a->path, NULL, a, NULL))
return -1;
}
if (!mfi.clean && mfi.blob.mode == a->mode &&
oideq(&mfi.blob.oid, &a->oid)) {
/*
* Getting here means we were attempting to merge a binary
* blob. Since we can't merge binaries, the merge algorithm
* just takes one side. But we don't want to copy the
* contents of one side to both paths; we'd rather use the
* original content at the given path for each path.
*/
oidcpy(&mfi.blob.oid, &b->oid);
mfi.blob.mode = b->mode;
}
add = &ci->ren2->dst_entry->stages[flip_stage(3)];
if (is_valid(add)) {
add->path = mfi.blob.path = b->path;
if (handle_file_collision(opt, b->path,
NULL, NULL,
ci->ren1->branch,
ci->ren2->branch,
add, &mfi.blob) < 0)
return -1;
} else {
char *new_path = find_path_for_conflict(opt, b->path,
ci->ren2->branch,
ci->ren1->branch);
if (update_file(opt, 0, &mfi.blob,
new_path ? new_path : b->path))
return -1;
free(new_path);
if (!opt->priv->call_depth &&
update_stages(opt, b->path, NULL, NULL, b))
return -1;
}
return 0;
}
static int handle_rename_rename_2to1(struct merge_options *opt,
struct rename_conflict_info *ci)
{
/* Two files, a & b, were renamed to the same thing, c. */
struct diff_filespec *a = ci->ren1->pair->one;
struct diff_filespec *b = ci->ren2->pair->one;
struct diff_filespec *c1 = ci->ren1->pair->two;
struct diff_filespec *c2 = ci->ren2->pair->two;
char *path = c1->path; /* == c2->path */
char *path_side_1_desc;
char *path_side_2_desc;
struct merge_file_info mfi_c1;
struct merge_file_info mfi_c2;
int ostage1, ostage2;
output(opt, 1, _("CONFLICT (rename/rename): "
"Rename %s->%s in %s. "
"Rename %s->%s in %s"),
a->path, c1->path, ci->ren1->branch,
b->path, c2->path, ci->ren2->branch);
path_side_1_desc = xstrfmt("version of %s from %s", path, a->path);
path_side_2_desc = xstrfmt("version of %s from %s", path, b->path);
ostage1 = ci->ren1->branch == opt->branch1 ? 3 : 2;
ostage2 = flip_stage(ostage1);
ci->ren1->src_entry->stages[ostage1].path = a->path;
ci->ren2->src_entry->stages[ostage2].path = b->path;
if (merge_mode_and_contents(opt, a, c1,
&ci->ren1->src_entry->stages[ostage1],
path_side_1_desc,
opt->branch1, opt->branch2,
1 + opt->priv->call_depth * 2, &mfi_c1) ||
merge_mode_and_contents(opt, b,
&ci->ren2->src_entry->stages[ostage2],
c2, path_side_2_desc,
opt->branch1, opt->branch2,
1 + opt->priv->call_depth * 2, &mfi_c2))
return -1;
free(path_side_1_desc);
free(path_side_2_desc);
mfi_c1.blob.path = path;
mfi_c2.blob.path = path;
return handle_file_collision(opt, path, a->path, b->path,
ci->ren1->branch, ci->ren2->branch,
&mfi_c1.blob, &mfi_c2.blob);
}
/*
* Get the diff_filepairs changed between o_tree and tree.
*/
static struct diff_queue_struct *get_diffpairs(struct merge_options *opt,
struct tree *o_tree,
struct tree *tree)
{
struct diff_queue_struct *ret;
struct diff_options opts;
repo_diff_setup(opt->repo, &opts);
opts.flags.recursive = 1;
opts.flags.rename_empty = 0;
opts.detect_rename = merge_detect_rename(opt);
/*
* We do not have logic to handle the detection of copies. In
* fact, it may not even make sense to add such logic: would we
* really want a change to a base file to be propagated through
* multiple other files by a merge?
*/
if (opts.detect_rename > DIFF_DETECT_RENAME)
opts.detect_rename = DIFF_DETECT_RENAME;
opts.rename_limit = (opt->rename_limit >= 0) ? opt->rename_limit : 7000;
opts.rename_score = opt->rename_score;
opts.show_rename_progress = opt->show_rename_progress;
opts.output_format = DIFF_FORMAT_NO_OUTPUT;
diff_setup_done(&opts);
diff_tree_oid(&o_tree->object.oid, &tree->object.oid, "", &opts);
diffcore_std(&opts);
if (opts.needed_rename_limit > opt->priv->needed_rename_limit)
opt->priv->needed_rename_limit = opts.needed_rename_limit;
ret = xmalloc(sizeof(*ret));
*ret = diff_queued_diff;
opts.output_format = DIFF_FORMAT_NO_OUTPUT;
diff_queued_diff.nr = 0;
diff_queued_diff.queue = NULL;
diff_flush(&opts);
return ret;
}
static int tree_has_path(struct repository *r, struct tree *tree,
const char *path)
{
struct object_id hashy;
unsigned short mode_o;
return !get_tree_entry(r,
&tree->object.oid, path,
&hashy, &mode_o);
}
/*
* Return a new string that replaces the beginning portion (which matches
* entry->dir), with entry->new_dir. In perl-speak:
* new_path_name = (old_path =~ s/entry->dir/entry->new_dir/);
* NOTE:
* Caller must ensure that old_path starts with entry->dir + '/'.
*/
static char *apply_dir_rename(struct dir_rename_entry *entry,
const char *old_path)
{
struct strbuf new_path = STRBUF_INIT;
int oldlen, newlen;
if (entry->non_unique_new_dir)
return NULL;
oldlen = strlen(entry->dir);
if (entry->new_dir.len == 0)
/*
* If someone renamed/merged a subdirectory into the root
* directory (e.g. 'some/subdir' -> ''), then we want to
* avoid returning
* '' + '/filename'
* as the rename; we need to make old_path + oldlen advance
* past the '/' character.
*/
oldlen++;
newlen = entry->new_dir.len + (strlen(old_path) - oldlen) + 1;
strbuf_grow(&new_path, newlen);
strbuf_addbuf(&new_path, &entry->new_dir);
strbuf_addstr(&new_path, &old_path[oldlen]);
return strbuf_detach(&new_path, NULL);
}
static void get_renamed_dir_portion(const char *old_path, const char *new_path,
char **old_dir, char **new_dir)
{
char *end_of_old, *end_of_new;
/* Default return values: NULL, meaning no rename */
*old_dir = NULL;
*new_dir = NULL;
/*
* For
* "a/b/c/d/e/foo.c" -> "a/b/some/thing/else/e/foo.c"
* the "e/foo.c" part is the same, we just want to know that
* "a/b/c/d" was renamed to "a/b/some/thing/else"
* so, for this example, this function returns "a/b/c/d" in
* *old_dir and "a/b/some/thing/else" in *new_dir.
*/
/*
* If the basename of the file changed, we don't care. We want
* to know which portion of the directory, if any, changed.
*/
end_of_old = strrchr(old_path, '/');
end_of_new = strrchr(new_path, '/');
/*
* If end_of_old is NULL, old_path wasn't in a directory, so there
* could not be a directory rename (our rule elsewhere that a
* directory which still exists is not considered to have been
* renamed means the root directory can never be renamed -- because
* the root directory always exists).
*/
if (!end_of_old)
return; /* Note: *old_dir and *new_dir are still NULL */
/*
* If new_path contains no directory (end_of_new is NULL), then we
* have a rename of old_path's directory to the root directory.
*/
if (!end_of_new) {
*old_dir = xstrndup(old_path, end_of_old - old_path);
*new_dir = xstrdup("");
return;
}
/* Find the first non-matching character traversing backwards */
while (*--end_of_new == *--end_of_old &&
end_of_old != old_path &&
end_of_new != new_path)
; /* Do nothing; all in the while loop */
/*
* If both got back to the beginning of their strings, then the
* directory didn't change at all, only the basename did.
*/
if (end_of_old == old_path && end_of_new == new_path &&
*end_of_old == *end_of_new)
return; /* Note: *old_dir and *new_dir are still NULL */
/*
* If end_of_new got back to the beginning of its string, and
* end_of_old got back to the beginning of some subdirectory, then
* we have a rename/merge of a subdirectory into the root, which
* needs slightly special handling.
*
* Note: There is no need to consider the opposite case, with a
* rename/merge of the root directory into some subdirectory
* because as noted above the root directory always exists so it
* cannot be considered to be renamed.
*/
if (end_of_new == new_path &&
end_of_old != old_path && end_of_old[-1] == '/') {
*old_dir = xstrndup(old_path, --end_of_old - old_path);
*new_dir = xstrdup("");
return;
}
/*
* We've found the first non-matching character in the directory
* paths. That means the current characters we were looking at
* were part of the first non-matching subdir name going back from
* the end of the strings. Get the whole name by advancing both
* end_of_old and end_of_new to the NEXT '/' character. That will
* represent the entire directory rename.
*
* The reason for the increment is cases like
* a/b/star/foo/whatever.c -> a/b/tar/foo/random.c
* After dropping the basename and going back to the first
* non-matching character, we're now comparing:
* a/b/s and a/b/
* and we want to be comparing:
* a/b/star/ and a/b/tar/
* but without the pre-increment, the one on the right would stay
* a/b/.
*/
end_of_old = strchr(++end_of_old, '/');
end_of_new = strchr(++end_of_new, '/');
/* Copy the old and new directories into *old_dir and *new_dir. */
*old_dir = xstrndup(old_path, end_of_old - old_path);
*new_dir = xstrndup(new_path, end_of_new - new_path);
}
static void remove_hashmap_entries(struct hashmap *dir_renames,
struct string_list *items_to_remove)
{
int i;
struct dir_rename_entry *entry;
for (i = 0; i < items_to_remove->nr; i++) {
entry = items_to_remove->items[i].util;
hashmap_remove(dir_renames, &entry->ent, NULL);
}
string_list_clear(items_to_remove, 0);
}
/*
* See if there is a directory rename for path, and if there are any file
* level conflicts for the renamed location. If there is a rename and
* there are no conflicts, return the new name. Otherwise, return NULL.
*/
static char *handle_path_level_conflicts(struct merge_options *opt,
const char *path,
struct dir_rename_entry *entry,
struct hashmap *collisions,
struct tree *tree)
{
char *new_path = NULL;
struct collision_entry *collision_ent;
int clean = 1;
struct strbuf collision_paths = STRBUF_INIT;
/*
* entry has the mapping of old directory name to new directory name
* that we want to apply to path.
*/
new_path = apply_dir_rename(entry, path);
if (!new_path) {
/* This should only happen when entry->non_unique_new_dir set */
if (!entry->non_unique_new_dir)
BUG("entry->non_unique_new_dir not set and !new_path");
output(opt, 1, _("CONFLICT (directory rename split): "
"Unclear where to place %s because directory "
"%s was renamed to multiple other directories, "
"with no destination getting a majority of the "
"files."),
path, entry->dir);
clean = 0;
return NULL;
}
/*
* The caller needs to have ensured that it has pre-populated
* collisions with all paths that map to new_path. Do a quick check
* to ensure that's the case.
*/
collision_ent = collision_find_entry(collisions, new_path);
if (!collision_ent)
BUG("collision_ent is NULL");
/*
* Check for one-sided add/add/.../add conflicts, i.e.
* where implicit renames from the other side doing
* directory rename(s) can affect this side of history
* to put multiple paths into the same location. Warn
* and bail on directory renames for such paths.
*/
if (collision_ent->reported_already) {
clean = 0;
} else if (tree_has_path(opt->repo, tree, new_path)) {
collision_ent->reported_already = 1;
strbuf_add_separated_string_list(&collision_paths, ", ",
&collision_ent->source_files);
output(opt, 1, _("CONFLICT (implicit dir rename): Existing "
"file/dir at %s in the way of implicit "
"directory rename(s) putting the following "
"path(s) there: %s."),
new_path, collision_paths.buf);
clean = 0;
} else if (collision_ent->source_files.nr > 1) {
collision_ent->reported_already = 1;
strbuf_add_separated_string_list(&collision_paths, ", ",
&collision_ent->source_files);
output(opt, 1, _("CONFLICT (implicit dir rename): Cannot map "
"more than one path to %s; implicit directory "
"renames tried to put these paths there: %s"),
new_path, collision_paths.buf);
clean = 0;
}
/* Free memory we no longer need */
strbuf_release(&collision_paths);
if (!clean && new_path) {
free(new_path);
return NULL;
}
return new_path;
}
/*
* There are a couple things we want to do at the directory level:
* 1. Check for both sides renaming to the same thing, in order to avoid
* implicit renaming of files that should be left in place. (See
* testcase 6b in t6043 for details.)
* 2. Prune directory renames if there are still files left in the
* original directory. These represent a partial directory rename,
* i.e. a rename where only some of the files within the directory
* were renamed elsewhere. (Technically, this could be done earlier
* in get_directory_renames(), except that would prevent us from
* doing the previous check and thus failing testcase 6b.)
* 3. Check for rename/rename(1to2) conflicts (at the directory level).
* In the future, we could potentially record this info as well and
* omit reporting rename/rename(1to2) conflicts for each path within
* the affected directories, thus cleaning up the merge output.
* NOTE: We do NOT check for rename/rename(2to1) conflicts at the
* directory level, because merging directories is fine. If it
* causes conflicts for files within those merged directories, then
* that should be detected at the individual path level.
*/
static void handle_directory_level_conflicts(struct merge_options *opt,
struct hashmap *dir_re_head,
struct tree *head,
struct hashmap *dir_re_merge,
struct tree *merge)
{
struct hashmap_iter iter;
struct dir_rename_entry *head_ent;
struct dir_rename_entry *merge_ent;
struct string_list remove_from_head = STRING_LIST_INIT_NODUP;
struct string_list remove_from_merge = STRING_LIST_INIT_NODUP;
hashmap_for_each_entry(dir_re_head, &iter, head_ent,
ent /* member name */) {
merge_ent = dir_rename_find_entry(dir_re_merge, head_ent->dir);
if (merge_ent &&
!head_ent->non_unique_new_dir &&
!merge_ent->non_unique_new_dir &&
!strbuf_cmp(&head_ent->new_dir, &merge_ent->new_dir)) {
/* 1. Renamed identically; remove it from both sides */
string_list_append(&remove_from_head,
head_ent->dir)->util = head_ent;
strbuf_release(&head_ent->new_dir);
string_list_append(&remove_from_merge,
merge_ent->dir)->util = merge_ent;
strbuf_release(&merge_ent->new_dir);
} else if (tree_has_path(opt->repo, head, head_ent->dir)) {
/* 2. This wasn't a directory rename after all */
string_list_append(&remove_from_head,
head_ent->dir)->util = head_ent;
strbuf_release(&head_ent->new_dir);
}
}
remove_hashmap_entries(dir_re_head, &remove_from_head);
remove_hashmap_entries(dir_re_merge, &remove_from_merge);
hashmap_for_each_entry(dir_re_merge, &iter, merge_ent,
ent /* member name */) {
head_ent = dir_rename_find_entry(dir_re_head, merge_ent->dir);
if (tree_has_path(opt->repo, merge, merge_ent->dir)) {
/* 2. This wasn't a directory rename after all */
string_list_append(&remove_from_merge,
merge_ent->dir)->util = merge_ent;
} else if (head_ent &&
!head_ent->non_unique_new_dir &&
!merge_ent->non_unique_new_dir) {
/* 3. rename/rename(1to2) */
/*
* We can assume it's not rename/rename(1to1) because
* that was case (1), already checked above. So we
* know that head_ent->new_dir and merge_ent->new_dir
* are different strings.
*/
output(opt, 1, _("CONFLICT (rename/rename): "
"Rename directory %s->%s in %s. "
"Rename directory %s->%s in %s"),
head_ent->dir, head_ent->new_dir.buf, opt->branch1,
head_ent->dir, merge_ent->new_dir.buf, opt->branch2);
string_list_append(&remove_from_head,
head_ent->dir)->util = head_ent;
strbuf_release(&head_ent->new_dir);
string_list_append(&remove_from_merge,
merge_ent->dir)->util = merge_ent;
strbuf_release(&merge_ent->new_dir);
}
}
remove_hashmap_entries(dir_re_head, &remove_from_head);
remove_hashmap_entries(dir_re_merge, &remove_from_merge);
}
static struct hashmap *get_directory_renames(struct diff_queue_struct *pairs)
{
struct hashmap *dir_renames;
struct hashmap_iter iter;
struct dir_rename_entry *entry;
int i;
/*
* Typically, we think of a directory rename as all files from a
* certain directory being moved to a target directory. However,
* what if someone first moved two files from the original
* directory in one commit, and then renamed the directory
* somewhere else in a later commit? At merge time, we just know
* that files from the original directory went to two different
* places, and that the bulk of them ended up in the same place.
* We want each directory rename to represent where the bulk of the
* files from that directory end up; this function exists to find
* where the bulk of the files went.
*
* The first loop below simply iterates through the list of file
* renames, finding out how often each directory rename pair
* possibility occurs.
*/
dir_renames = xmalloc(sizeof(*dir_renames));
dir_rename_init(dir_renames);
for (i = 0; i < pairs->nr; ++i) {
struct string_list_item *item;
int *count;
struct diff_filepair *pair = pairs->queue[i];
char *old_dir, *new_dir;
/* File not part of directory rename if it wasn't renamed */
if (pair->status != 'R')
continue;
get_renamed_dir_portion(pair->one->path, pair->two->path,
&old_dir, &new_dir);
if (!old_dir)
/* Directory didn't change at all; ignore this one. */
continue;
entry = dir_rename_find_entry(dir_renames, old_dir);
if (!entry) {
entry = xmalloc(sizeof(*entry));
dir_rename_entry_init(entry, old_dir);
hashmap_put(dir_renames, &entry->ent);
} else {
free(old_dir);
}
item = string_list_lookup(&entry->possible_new_dirs, new_dir);
if (!item) {
item = string_list_insert(&entry->possible_new_dirs,
new_dir);
item->util = xcalloc(1, sizeof(int));
} else {
free(new_dir);
}
count = item->util;
*count += 1;
}
/*
* For each directory with files moved out of it, we find out which
* target directory received the most files so we can declare it to
* be the "winning" target location for the directory rename. This
* winner gets recorded in new_dir. If there is no winner
* (multiple target directories received the same number of files),
* we set non_unique_new_dir. Once we've determined the winner (or
* that there is no winner), we no longer need possible_new_dirs.
*/
hashmap_for_each_entry(dir_renames, &iter, entry,
ent /* member name */) {
int max = 0;
int bad_max = 0;
char *best = NULL;
for (i = 0; i < entry->possible_new_dirs.nr; i++) {
int *count = entry->possible_new_dirs.items[i].util;
if (*count == max)
bad_max = max;
else if (*count > max) {
max = *count;
best = entry->possible_new_dirs.items[i].string;
}
}
if (bad_max == max)
entry->non_unique_new_dir = 1;
else {
assert(entry->new_dir.len == 0);
strbuf_addstr(&entry->new_dir, best);
}
/*
* The relevant directory sub-portion of the original full
* filepaths were xstrndup'ed before inserting into
* possible_new_dirs, and instead of manually iterating the
* list and free'ing each, just lie and tell
* possible_new_dirs that it did the strdup'ing so that it
* will free them for us.
*/
entry->possible_new_dirs.strdup_strings = 1;
string_list_clear(&entry->possible_new_dirs, 1);
}
return dir_renames;
}
static struct dir_rename_entry *check_dir_renamed(const char *path,
struct hashmap *dir_renames)
{
char *temp = xstrdup(path);
char *end;
struct dir_rename_entry *entry = NULL;
while ((end = strrchr(temp, '/'))) {
*end = '\0';
entry = dir_rename_find_entry(dir_renames, temp);
if (entry)
break;
}
free(temp);
return entry;
}
static void compute_collisions(struct hashmap *collisions,
struct hashmap *dir_renames,
struct diff_queue_struct *pairs)
{
int i;
/*
* Multiple files can be mapped to the same path due to directory
* renames done by the other side of history. Since that other
* side of history could have merged multiple directories into one,
* if our side of history added the same file basename to each of
* those directories, then all N of them would get implicitly
* renamed by the directory rename detection into the same path,
* and we'd get an add/add/.../add conflict, and all those adds
* from *this* side of history. This is not representable in the
* index, and users aren't going to easily be able to make sense of
* it. So we need to provide a good warning about what's
* happening, and fall back to no-directory-rename detection
* behavior for those paths.
*
* See testcases 9e and all of section 5 from t6043 for examples.
*/
collision_init(collisions);
for (i = 0; i < pairs->nr; ++i) {
struct dir_rename_entry *dir_rename_ent;
struct collision_entry *collision_ent;
char *new_path;
struct diff_filepair *pair = pairs->queue[i];
if (pair->status != 'A' && pair->status != 'R')
continue;
dir_rename_ent = check_dir_renamed(pair->two->path,
dir_renames);
if (!dir_rename_ent)
continue;
new_path = apply_dir_rename(dir_rename_ent, pair->two->path);
if (!new_path)
/*
* dir_rename_ent->non_unique_new_path is true, which
* means there is no directory rename for us to use,
* which means it won't cause us any additional
* collisions.
*/
continue;
collision_ent = collision_find_entry(collisions, new_path);
if (!collision_ent) {
CALLOC_ARRAY(collision_ent, 1);
hashmap_entry_init(&collision_ent->ent,
strhash(new_path));
hashmap_put(collisions, &collision_ent->ent);
collision_ent->target_file = new_path;
} else {
free(new_path);
}
string_list_insert(&collision_ent->source_files,
pair->two->path);
}
}
static char *check_for_directory_rename(struct merge_options *opt,
const char *path,
struct tree *tree,
struct hashmap *dir_renames,
struct hashmap *dir_rename_exclusions,
struct hashmap *collisions,
int *clean_merge)
{
char *new_path = NULL;
struct dir_rename_entry *entry = check_dir_renamed(path, dir_renames);
struct dir_rename_entry *oentry = NULL;
if (!entry)
return new_path;
/*
* This next part is a little weird. We do not want to do an
* implicit rename into a directory we renamed on our side, because
* that will result in a spurious rename/rename(1to2) conflict. An
* example:
* Base commit: dumbdir/afile, otherdir/bfile
* Side 1: smrtdir/afile, otherdir/bfile
* Side 2: dumbdir/afile, dumbdir/bfile
* Here, while working on Side 1, we could notice that otherdir was
* renamed/merged to dumbdir, and change the diff_filepair for
* otherdir/bfile into a rename into dumbdir/bfile. However, Side
* 2 will notice the rename from dumbdir to smrtdir, and do the
* transitive rename to move it from dumbdir/bfile to
* smrtdir/bfile. That gives us bfile in dumbdir vs being in
* smrtdir, a rename/rename(1to2) conflict. We really just want
* the file to end up in smrtdir. And the way to achieve that is
* to not let Side1 do the rename to dumbdir, since we know that is
* the source of one of our directory renames.
*
* That's why oentry and dir_rename_exclusions is here.
*
* As it turns out, this also prevents N-way transient rename
* confusion; See testcases 9c and 9d of t6043.
*/
oentry = dir_rename_find_entry(dir_rename_exclusions, entry->new_dir.buf);
if (oentry) {
output(opt, 1, _("WARNING: Avoiding applying %s -> %s rename "
"to %s, because %s itself was renamed."),
entry->dir, entry->new_dir.buf, path, entry->new_dir.buf);
} else {
new_path = handle_path_level_conflicts(opt, path, entry,
collisions, tree);
*clean_merge &= (new_path != NULL);
}
return new_path;
}
static void apply_directory_rename_modifications(struct merge_options *opt,
struct diff_filepair *pair,
char *new_path,
struct rename *re,
struct tree *tree,
struct tree *o_tree,
struct tree *a_tree,
struct tree *b_tree,
struct string_list *entries)
{
struct string_list_item *item;
int stage = (tree == a_tree ? 2 : 3);
int update_wd;
/*
* In all cases where we can do directory rename detection,
* unpack_trees() will have read pair->two->path into the
* index and the working copy. We need to remove it so that
* we can instead place it at new_path. It is guaranteed to
* not be untracked (unpack_trees() would have errored out
* saying the file would have been overwritten), but it might
* be dirty, though.
*/
update_wd = !was_dirty(opt, pair->two->path);
if (!update_wd)
output(opt, 1, _("Refusing to lose dirty file at %s"),
pair->two->path);
remove_file(opt, 1, pair->two->path, !update_wd);
/* Find or create a new re->dst_entry */
item = string_list_lookup(entries, new_path);
if (item) {
/*
* Since we're renaming on this side of history, and it's
* due to a directory rename on the other side of history
* (which we only allow when the directory in question no
* longer exists on the other side of history), the
* original entry for re->dst_entry is no longer
* necessary...
*/
re->dst_entry->processed = 1;
/*
* ...because we'll be using this new one.
*/
re->dst_entry = item->util;
} else {
/*
* re->dst_entry is for the before-dir-rename path, and we
* need it to hold information for the after-dir-rename
* path. Before creating a new entry, we need to mark the
* old one as unnecessary (...unless it is shared by
* src_entry, i.e. this didn't use to be a rename, in which
* case we can just allow the normal processing to happen
* for it).
*/
if (pair->status == 'R')
re->dst_entry->processed = 1;
re->dst_entry = insert_stage_data(opt->repo, new_path,
o_tree, a_tree, b_tree,
entries);
item = string_list_insert(entries, new_path);
item->util = re->dst_entry;
}
/*
* Update the stage_data with the information about the path we are
* moving into place. That slot will be empty and available for us
* to write to because of the collision checks in
* handle_path_level_conflicts(). In other words,
* re->dst_entry->stages[stage].oid will be the null_oid, so it's
* open for us to write to.
*
* It may be tempting to actually update the index at this point as
* well, using update_stages_for_stage_data(), but as per the big
* "NOTE" in update_stages(), doing so will modify the current
* in-memory index which will break calls to would_lose_untracked()
* that we need to make. Instead, we need to just make sure that
* the various handle_rename_*() functions update the index
* explicitly rather than relying on unpack_trees() to have done it.
*/
get_tree_entry(opt->repo,
&tree->object.oid,
pair->two->path,
&re->dst_entry->stages[stage].oid,
&re->dst_entry->stages[stage].mode);
/*
* Record the original change status (or 'type' of change). If it
* was originally an add ('A'), this lets us differentiate later
* between a RENAME_DELETE conflict and RENAME_VIA_DIR (they
* otherwise look the same). If it was originally a rename ('R'),
* this lets us remember and report accurately about the transitive
* renaming that occurred via the directory rename detection. Also,
* record the original destination name.
*/
re->dir_rename_original_type = pair->status;
re->dir_rename_original_dest = pair->two->path;
/*
* We don't actually look at pair->status again, but it seems
* pedagogically correct to adjust it.
*/
pair->status = 'R';
/*
* Finally, record the new location.
*/
pair->two->path = new_path;
}
/*
* Get information of all renames which occurred in 'pairs', making use of
* any implicit directory renames inferred from the other side of history.
* 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 *opt,
const char *branch,
struct diff_queue_struct *pairs,
struct hashmap *dir_renames,
struct hashmap *dir_rename_exclusions,
struct tree *tree,
struct tree *o_tree,
struct tree *a_tree,
struct tree *b_tree,
struct string_list *entries,
int *clean_merge)
{
int i;
struct hashmap collisions;
struct hashmap_iter iter;
struct collision_entry *e;
struct string_list *renames;
compute_collisions(&collisions, dir_renames, pairs);
CALLOC_ARRAY(renames, 1);
for (i = 0; i < pairs->nr; ++i) {
struct string_list_item *item;
struct rename *re;
struct diff_filepair *pair = pairs->queue[i];
char *new_path; /* non-NULL only with directory renames */
if (pair->status != 'A' && pair->status != 'R') {
diff_free_filepair(pair);
continue;
}
new_path = check_for_directory_rename(opt, pair->two->path, tree,
dir_renames,
dir_rename_exclusions,
&collisions,
clean_merge);
if (pair->status != 'R' && !new_path) {
diff_free_filepair(pair);
continue;
}
re = xmalloc(sizeof(*re));
re->processed = 0;
re->pair = pair;
re->branch = branch;
re->dir_rename_original_type = '\0';
re->dir_rename_original_dest = NULL;
item = string_list_lookup(entries, re->pair->one->path);
if (!item)
re->src_entry = insert_stage_data(opt->repo,
re->pair->one->path,
o_tree, a_tree, b_tree, entries);
else
re->src_entry = item->util;
item = string_list_lookup(entries, re->pair->two->path);
if (!item)
re->dst_entry = insert_stage_data(opt->repo,
re->pair->two->path,
o_tree, a_tree, b_tree, entries);
else
re->dst_entry = item->util;
item = string_list_insert(renames, pair->one->path);
item->util = re;
if (new_path)
apply_directory_rename_modifications(opt, pair, new_path,
re, tree, o_tree,
a_tree, b_tree,
entries);
}
hashmap_for_each_entry(&collisions, &iter, e,
ent /* member name */) {
free(e->target_file);
string_list_clear(&e->source_files, 0);
}
hashmap_clear_and_free(&collisions, struct collision_entry, ent);
return renames;
}
static int process_renames(struct merge_options *opt,
struct string_list *a_renames,
struct string_list *b_renames)
{
int clean_merge = 1, i, j;
struct string_list a_by_dst = STRING_LIST_INIT_NODUP;
struct string_list b_by_dst = STRING_LIST_INIT_NODUP;
const struct rename *sre;
/*
* FIXME: As string-list.h notes, it's O(n^2) to build a sorted
* string_list one-by-one, but O(n log n) to build it unsorted and
* then sort it. Note that as we build the list, we do not need to
* check if the existing destination path is already in the list,
* because the structure of diffcore_rename guarantees we won't
* have duplicates.
*/
for (i = 0; i < a_renames->nr; i++) {
sre = a_renames->items[i].util;
string_list_insert(&a_by_dst, sre->pair->two->path)->util
= (void *)sre;
}
for (i = 0; i < b_renames->nr; i++) {
sre = b_renames->items[i].util;
string_list_insert(&b_by_dst, sre->pair->two->path)->util
= (void *)sre;
}
for (i = 0, j = 0; i < a_renames->nr || j < b_renames->nr;) {
struct string_list *renames1, *renames2Dst;
struct rename *ren1 = NULL, *ren2 = NULL;
const char *ren1_src, *ren1_dst;
struct string_list_item *lookup;
if (i >= a_renames->nr) {
ren2 = b_renames->items[j++].util;
} else if (j >= b_renames->nr) {
ren1 = a_renames->items[i++].util;
} else {
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)
ren2 = b_renames->items[j++].util;
}
/* TODO: refactor, so that 1/2 are not needed */
if (ren1) {
renames1 = a_renames;
renames2Dst = &b_by_dst;
} else {
renames1 = b_renames;
renames2Dst = &a_by_dst;
SWAP(ren2, ren1);
}
if (ren1->processed)
continue;
ren1->processed = 1;
ren1->dst_entry->processed = 1;
/* BUG: We should only mark src_entry as processed if we
* are not dealing with a rename + add-source case.
*/
ren1->src_entry->processed = 1;
ren1_src = ren1->pair->one->path;
ren1_dst = ren1->pair->two->path;
if (ren2) {
/* One file renamed on both sides */
const char *ren2_src = ren2->pair->one->path;
const char *ren2_dst = ren2->pair->two->path;
enum rename_type rename_type;
if (strcmp(ren1_src, ren2_src) != 0)
BUG("ren1_src != ren2_src");
ren2->dst_entry->processed = 1;
ren2->processed = 1;
if (strcmp(ren1_dst, ren2_dst) != 0) {
rename_type = RENAME_ONE_FILE_TO_TWO;
clean_merge = 0;
} else {
rename_type = RENAME_ONE_FILE_TO_ONE;
/* BUG: We should only remove ren1_src in
* the base stage (think of rename +
* add-source cases).
*/
remove_file(opt, 1, ren1_src, 1);
update_entry(ren1->dst_entry,
ren1->pair->one,
ren1->pair->two,
ren2->pair->two);
}
setup_rename_conflict_info(rename_type, opt, ren1, ren2);
} else if ((lookup = string_list_lookup(renames2Dst, ren1_dst))) {
/* Two different files renamed to the same thing */
char *ren2_dst;
ren2 = lookup->util;
ren2_dst = ren2->pair->two->path;
if (strcmp(ren1_dst, ren2_dst) != 0)
BUG("ren1_dst != ren2_dst");
clean_merge = 0;
ren2->processed = 1;
/*
* BUG: We should only mark src_entry as processed
* if we are not dealing with a rename + add-source
* case.
*/
ren2->src_entry->processed = 1;
setup_rename_conflict_info(RENAME_TWO_FILES_TO_ONE,
opt, ren1, ren2);
} else {
/* Renamed in 1, maybe changed in 2 */
/* we only use sha1 and mode of these */
struct diff_filespec src_other, dst_other;
int try_merge;
/*
* unpack_trees loads entries from common-commit
* into stage 1, from head-commit into stage 2, and
* from merge-commit into stage 3. We keep track
* of which side corresponds to the rename.
*/
int renamed_stage = a_renames == renames1 ? 2 : 3;
int other_stage = a_renames == renames1 ? 3 : 2;
/*
* Directory renames have a funny corner case...
*/
int renamed_to_self = !strcmp(ren1_src, ren1_dst);
/* BUG: We should only remove ren1_src in the base
* stage and in other_stage (think of rename +
* add-source case).
*/
if (!renamed_to_self)
remove_file(opt, 1, ren1_src,
renamed_stage == 2 ||
!was_tracked(opt, ren1_src));
oidcpy(&src_other.oid,
&ren1->src_entry->stages[other_stage].oid);
src_other.mode = ren1->src_entry->stages[other_stage].mode;
oidcpy(&dst_other.oid,
&ren1->dst_entry->stages[other_stage].oid);
dst_other.mode = ren1->dst_entry->stages[other_stage].mode;
try_merge = 0;
if (oideq(&src_other.oid, null_oid()) &&
ren1->dir_rename_original_type == 'A') {
setup_rename_conflict_info(RENAME_VIA_DIR,
opt, ren1, NULL);
} else if (renamed_to_self) {
setup_rename_conflict_info(RENAME_NORMAL,
opt, ren1, NULL);
} else if (oideq(&src_other.oid, null_oid())) {
setup_rename_conflict_info(RENAME_DELETE,
opt, ren1, NULL);
} else if ((dst_other.mode == ren1->pair->two->mode) &&
oideq(&dst_other.oid, &ren1->pair->two->oid)) {
/*
* Added file on the other side identical to
* the file being renamed: clean merge.
* Also, there is no need to overwrite the
* file already in the working copy, so call
* update_file_flags() instead of
* update_file().
*/
if (update_file_flags(opt,
ren1->pair->two,
ren1_dst,
1, /* update_cache */
0 /* update_wd */))
clean_merge = -1;
} else if (!oideq(&dst_other.oid, null_oid())) {
/*
* Probably not a clean merge, but it's
* premature to set clean_merge to 0 here,
* because if the rename merges cleanly and
* the merge exactly matches the newly added
* file, then the merge will be clean.
*/
setup_rename_conflict_info(RENAME_ADD,
opt, ren1, NULL);
} else
try_merge = 1;
if (clean_merge < 0)
goto cleanup_and_return;
if (try_merge) {
struct diff_filespec *o, *a, *b;
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;
}
update_entry(ren1->dst_entry, o, a, b);
setup_rename_conflict_info(RENAME_NORMAL,
opt, ren1, NULL);
}
}
}
cleanup_and_return:
string_list_clear(&a_by_dst, 0);
string_list_clear(&b_by_dst, 0);
return clean_merge;
}
struct rename_info {
struct string_list *head_renames;
struct string_list *merge_renames;
};
static void initial_cleanup_rename(struct diff_queue_struct *pairs,
struct hashmap *dir_renames)
{
struct hashmap_iter iter;
struct dir_rename_entry *e;
hashmap_for_each_entry(dir_renames, &iter, e,
ent /* member name */) {
free(e->dir);
strbuf_release(&e->new_dir);
/* possible_new_dirs already cleared in get_directory_renames */
}
hashmap_clear_and_free(dir_renames, struct dir_rename_entry, ent);