git/resolve-undo.c
Junio C Hamano 5bb67fb7ab Merge branch 'jc/unresolve-removal'
"checkout --merge -- path" and "update-index --unresolve path" did
not resurrect conflicted state that was resolved to remove path,
but now they do.

* jc/unresolve-removal:
  checkout: allow "checkout -m path" to unmerge removed paths
  checkout/restore: add basic tests for --merge
  checkout/restore: refuse unmerging paths unless checking out of the index
  update-index: remove stale fallback code for "--unresolve"
  update-index: use unmerge_index_entry() to support removal
  resolve-undo: allow resurrecting conflicted state that resolved to deletion
  update-index: do not read HEAD and MERGE_HEAD unconditionally
2023-10-02 11:20:00 -07:00

176 lines
4.1 KiB
C

#include "git-compat-util.h"
#include "dir.h"
#include "hash.h"
#include "read-cache.h"
#include "resolve-undo.h"
#include "sparse-index.h"
#include "string-list.h"
/* The only error case is to run out of memory in string-list */
void record_resolve_undo(struct index_state *istate, struct cache_entry *ce)
{
struct string_list_item *lost;
struct resolve_undo_info *ui;
struct string_list *resolve_undo;
int stage = ce_stage(ce);
if (!stage)
return;
if (!istate->resolve_undo) {
CALLOC_ARRAY(resolve_undo, 1);
resolve_undo->strdup_strings = 1;
istate->resolve_undo = resolve_undo;
}
resolve_undo = istate->resolve_undo;
lost = string_list_insert(resolve_undo, ce->name);
if (!lost->util)
lost->util = xcalloc(1, sizeof(*ui));
ui = lost->util;
oidcpy(&ui->oid[stage - 1], &ce->oid);
ui->mode[stage - 1] = ce->ce_mode;
}
void resolve_undo_write(struct strbuf *sb, struct string_list *resolve_undo)
{
struct string_list_item *item;
for_each_string_list_item(item, resolve_undo) {
struct resolve_undo_info *ui = item->util;
int i;
if (!ui)
continue;
strbuf_addstr(sb, item->string);
strbuf_addch(sb, 0);
for (i = 0; i < 3; i++)
strbuf_addf(sb, "%o%c", ui->mode[i], 0);
for (i = 0; i < 3; i++) {
if (!ui->mode[i])
continue;
strbuf_add(sb, ui->oid[i].hash, the_hash_algo->rawsz);
}
}
}
struct string_list *resolve_undo_read(const char *data, unsigned long size)
{
struct string_list *resolve_undo;
size_t len;
char *endptr;
int i;
const unsigned rawsz = the_hash_algo->rawsz;
CALLOC_ARRAY(resolve_undo, 1);
resolve_undo->strdup_strings = 1;
while (size) {
struct string_list_item *lost;
struct resolve_undo_info *ui;
len = strlen(data) + 1;
if (size <= len)
goto error;
lost = string_list_insert(resolve_undo, data);
if (!lost->util)
lost->util = xcalloc(1, sizeof(*ui));
ui = lost->util;
size -= len;
data += len;
for (i = 0; i < 3; i++) {
ui->mode[i] = strtoul(data, &endptr, 8);
if (!endptr || endptr == data || *endptr)
goto error;
len = (endptr + 1) - (char*)data;
if (size <= len)
goto error;
size -= len;
data += len;
}
for (i = 0; i < 3; i++) {
if (!ui->mode[i])
continue;
if (size < rawsz)
goto error;
oidread(&ui->oid[i], (const unsigned char *)data);
size -= rawsz;
data += rawsz;
}
}
return resolve_undo;
error:
string_list_clear(resolve_undo, 1);
error("Index records invalid resolve-undo information");
return NULL;
}
void resolve_undo_clear_index(struct index_state *istate)
{
struct string_list *resolve_undo = istate->resolve_undo;
if (!resolve_undo)
return;
string_list_clear(resolve_undo, 1);
free(resolve_undo);
istate->resolve_undo = NULL;
istate->cache_changed |= RESOLVE_UNDO_CHANGED;
}
int unmerge_index_entry(struct index_state *istate, const char *path,
struct resolve_undo_info *ru, unsigned ce_flags)
{
int i = index_name_pos(istate, path, strlen(path));
if (i < 0) {
/* unmerged? */
i = -i - 1;
if (i < istate->cache_nr &&
!strcmp(istate->cache[i]->name, path))
/* yes, it is already unmerged */
return 0;
/* fallthru: resolved to removal */
} else {
/* merged - remove it to replace it with unmerged entries */
remove_index_entry_at(istate, i);
}
for (i = 0; i < 3; i++) {
struct cache_entry *ce;
if (!ru->mode[i])
continue;
ce = make_cache_entry(istate, ru->mode[i], &ru->oid[i],
path, i + 1, 0);
ce->ce_flags |= ce_flags;
if (add_index_entry(istate, ce, ADD_CACHE_OK_TO_ADD))
return error("cannot unmerge '%s'", path);
}
return 0;
}
void unmerge_index(struct index_state *istate, const struct pathspec *pathspec,
unsigned ce_flags)
{
struct string_list_item *item;
if (!istate->resolve_undo)
return;
/* TODO: audit for interaction with sparse-index. */
ensure_full_index(istate);
for_each_string_list_item(item, istate->resolve_undo) {
const char *path = item->string;
struct resolve_undo_info *ru = item->util;
if (!item->util)
continue;
if (!match_pathspec(istate, pathspec,
item->string, strlen(item->string),
0, NULL, 0))
continue;
unmerge_index_entry(istate, path, ru, ce_flags);
free(ru);
item->util = NULL;
}
}