#include "cache.h" #include "config.h" #include "lockfile.h" #include "string-list.h" #include "rerere.h" #include "xdiff-interface.h" #include "dir.h" #include "resolve-undo.h" #include "ll-merge.h" #include "attr.h" #include "pathspec.h" #include "object-store.h" #include "sha1-lookup.h" #define RESOLVED 0 #define PUNTED 1 #define THREE_STAGED 2 void *RERERE_RESOLVED = &RERERE_RESOLVED; /* if rerere_enabled == -1, fall back to detection of .git/rr-cache */ static int rerere_enabled = -1; /* automatically update cleanly resolved paths to the index */ static int rerere_autoupdate; static int rerere_dir_nr; static int rerere_dir_alloc; #define RR_HAS_POSTIMAGE 1 #define RR_HAS_PREIMAGE 2 static struct rerere_dir { unsigned char sha1[20]; int status_alloc, status_nr; unsigned char *status; } **rerere_dir; static void free_rerere_dirs(void) { int i; for (i = 0; i < rerere_dir_nr; i++) { free(rerere_dir[i]->status); free(rerere_dir[i]); } FREE_AND_NULL(rerere_dir); rerere_dir_nr = rerere_dir_alloc = 0; } static void free_rerere_id(struct string_list_item *item) { free(item->util); } static const char *rerere_id_hex(const struct rerere_id *id) { return sha1_to_hex(id->collection->sha1); } static void fit_variant(struct rerere_dir *rr_dir, int variant) { variant++; ALLOC_GROW(rr_dir->status, variant, rr_dir->status_alloc); if (rr_dir->status_nr < variant) { memset(rr_dir->status + rr_dir->status_nr, '\0', variant - rr_dir->status_nr); rr_dir->status_nr = variant; } } static void assign_variant(struct rerere_id *id) { int variant; struct rerere_dir *rr_dir = id->collection; variant = id->variant; if (variant < 0) { for (variant = 0; variant < rr_dir->status_nr; variant++) if (!rr_dir->status[variant]) break; } fit_variant(rr_dir, variant); id->variant = variant; } const char *rerere_path(const struct rerere_id *id, const char *file) { if (!file) return git_path("rr-cache/%s", rerere_id_hex(id)); if (id->variant <= 0) return git_path("rr-cache/%s/%s", rerere_id_hex(id), file); return git_path("rr-cache/%s/%s.%d", rerere_id_hex(id), file, id->variant); } static int is_rr_file(const char *name, const char *filename, int *variant) { const char *suffix; char *ep; if (!strcmp(name, filename)) { *variant = 0; return 1; } if (!skip_prefix(name, filename, &suffix) || *suffix != '.') return 0; errno = 0; *variant = strtol(suffix + 1, &ep, 10); if (errno || *ep) return 0; return 1; } static void scan_rerere_dir(struct rerere_dir *rr_dir) { struct dirent *de; DIR *dir = opendir(git_path("rr-cache/%s", sha1_to_hex(rr_dir->sha1))); if (!dir) return; while ((de = readdir(dir)) != NULL) { int variant; if (is_rr_file(de->d_name, "postimage", &variant)) { fit_variant(rr_dir, variant); rr_dir->status[variant] |= RR_HAS_POSTIMAGE; } else if (is_rr_file(de->d_name, "preimage", &variant)) { fit_variant(rr_dir, variant); rr_dir->status[variant] |= RR_HAS_PREIMAGE; } } closedir(dir); } static const unsigned char *rerere_dir_sha1(size_t i, void *table) { struct rerere_dir **rr_dir = table; return rr_dir[i]->sha1; } static struct rerere_dir *find_rerere_dir(const char *hex) { unsigned char sha1[20]; struct rerere_dir *rr_dir; int pos; if (get_sha1_hex(hex, sha1)) return NULL; /* BUG */ pos = sha1_pos(sha1, rerere_dir, rerere_dir_nr, rerere_dir_sha1); if (pos < 0) { rr_dir = xmalloc(sizeof(*rr_dir)); hashcpy(rr_dir->sha1, sha1); rr_dir->status = NULL; rr_dir->status_nr = 0; rr_dir->status_alloc = 0; pos = -1 - pos; /* Make sure the array is big enough ... */ ALLOC_GROW(rerere_dir, rerere_dir_nr + 1, rerere_dir_alloc); /* ... and add it in. */ rerere_dir_nr++; MOVE_ARRAY(rerere_dir + pos + 1, rerere_dir + pos, rerere_dir_nr - pos - 1); rerere_dir[pos] = rr_dir; scan_rerere_dir(rr_dir); } return rerere_dir[pos]; } static int has_rerere_resolution(const struct rerere_id *id) { const int both = RR_HAS_POSTIMAGE|RR_HAS_PREIMAGE; int variant = id->variant; if (variant < 0) return 0; return ((id->collection->status[variant] & both) == both); } static struct rerere_id *new_rerere_id_hex(char *hex) { struct rerere_id *id = xmalloc(sizeof(*id)); id->collection = find_rerere_dir(hex); id->variant = -1; /* not known yet */ return id; } static struct rerere_id *new_rerere_id(unsigned char *sha1) { return new_rerere_id_hex(sha1_to_hex(sha1)); } /* * $GIT_DIR/MERGE_RR file is a collection of records, each of which is * "conflict ID", a HT and pathname, terminated with a NUL, and is * used to keep track of the set of paths that "rerere" may need to * work on (i.e. what is left by the previous invocation of "git * rerere" during the current conflict resolution session). */ static void read_rr(struct string_list *rr) { struct strbuf buf = STRBUF_INIT; FILE *in = fopen_or_warn(git_path_merge_rr(the_repository), "r"); if (!in) return; while (!strbuf_getwholeline(&buf, in, '\0')) { char *path; unsigned char sha1[20]; struct rerere_id *id; int variant; /* There has to be the hash, tab, path and then NUL */ if (buf.len < 42 || get_sha1_hex(buf.buf, sha1)) die("corrupt MERGE_RR"); if (buf.buf[40] != '.') { variant = 0; path = buf.buf + 40; } else { errno = 0; variant = strtol(buf.buf + 41, &path, 10); if (errno) die("corrupt MERGE_RR"); } if (*(path++) != '\t') die("corrupt MERGE_RR"); buf.buf[40] = '\0'; id = new_rerere_id_hex(buf.buf); id->variant = variant; string_list_insert(rr, path)->util = id; } strbuf_release(&buf); fclose(in); } static struct lock_file write_lock; static int write_rr(struct string_list *rr, int out_fd) { int i; for (i = 0; i < rr->nr; i++) { struct strbuf buf = STRBUF_INIT; struct rerere_id *id; assert(rr->items[i].util != RERERE_RESOLVED); id = rr->items[i].util; if (!id) continue; assert(id->variant >= 0); if (0 < id->variant) strbuf_addf(&buf, "%s.%d\t%s%c", rerere_id_hex(id), id->variant, rr->items[i].string, 0); else strbuf_addf(&buf, "%s\t%s%c", rerere_id_hex(id), rr->items[i].string, 0); if (write_in_full(out_fd, buf.buf, buf.len) < 0) die("unable to write rerere record"); strbuf_release(&buf); } if (commit_lock_file(&write_lock) != 0) die("unable to write rerere record"); return 0; } /* * "rerere" interacts with conflicted file contents using this I/O * abstraction. It reads a conflicted contents from one place via * "getline()" method, and optionally can write it out after * normalizing the conflicted hunks to the "output". Subclasses of * rerere_io embed this structure at the beginning of their own * rerere_io object. */ struct rerere_io { int (*getline)(struct strbuf *, struct rerere_io *); FILE *output; int wrerror; /* some more stuff */ }; static void ferr_write(const void *p, size_t count, FILE *fp, int *err) { if (!count || *err) return; if (fwrite(p, count, 1, fp) != 1) *err = errno; } static inline void ferr_puts(const char *s, FILE *fp, int *err) { ferr_write(s, strlen(s), fp, err); } static void rerere_io_putstr(const char *str, struct rerere_io *io) { if (io->output) ferr_puts(str, io->output, &io->wrerror); } /* * Write a conflict marker to io->output (if defined). */ static void rerere_io_putconflict(int ch, int size, struct rerere_io *io) { char buf[64]; while (size) { if (size <= sizeof(buf) - 2) { memset(buf, ch, size); buf[size] = '\n'; buf[size + 1] = '\0'; size = 0; } else { int sz = sizeof(buf) - 1; /* * Make sure we will not write everything out * in this round by leaving at least 1 byte * for the next round, giving the next round * a chance to add the terminating LF. Yuck. */ if (size <= sz) sz -= (sz - size) + 1; memset(buf, ch, sz); buf[sz] = '\0'; size -= sz; } rerere_io_putstr(buf, io); } } static void rerere_io_putmem(const char *mem, size_t sz, struct rerere_io *io) { if (io->output) ferr_write(mem, sz, io->output, &io->wrerror); } /* * Subclass of rerere_io that reads from an on-disk file */ struct rerere_io_file { struct rerere_io io; FILE *input; }; /* * ... and its getline() method implementation */ static int rerere_file_getline(struct strbuf *sb, struct rerere_io *io_) { struct rerere_io_file *io = (struct rerere_io_file *)io_; return strbuf_getwholeline(sb, io->input, '\n'); } /* * Require the exact number of conflict marker letters, no more, no * less, followed by SP or any whitespace * (including LF). */ static int is_cmarker(char *buf, int marker_char, int marker_size) { int want_sp; /* * The beginning of our version and the end of their version * always are labeled like "<<<<< ours" or ">>>>> theirs", * hence we set want_sp for them. Note that the version from * the common ancestor in diff3-style output is not always * labelled (e.g. "||||| common" is often seen but "|||||" * alone is also valid), so we do not set want_sp. */ want_sp = (marker_char == '<') || (marker_char == '>'); while (marker_size--) if (*buf++ != marker_char) return 0; if (want_sp && *buf != ' ') return 0; return isspace(*buf); } /* * Read contents a file with conflicts, normalize the conflicts * by (1) discarding the common ancestor version in diff3-style, * (2) reordering our side and their side so that whichever sorts * alphabetically earlier comes before the other one, while * computing the "conflict ID", which is just an SHA-1 hash of * one side of the conflict, NUL, the other side of the conflict, * and NUL concatenated together. * * Return the number of conflict hunks found. * * NEEDSWORK: the logic and theory of operation behind this conflict * normalization may deserve to be documented somewhere, perhaps in * Documentation/technical/rerere.txt. */ static int handle_path(unsigned char *sha1, struct rerere_io *io, int marker_size) { git_SHA_CTX ctx; int hunk_no = 0; enum { RR_CONTEXT = 0, RR_SIDE_1, RR_SIDE_2, RR_ORIGINAL } hunk = RR_CONTEXT; struct strbuf one = STRBUF_INIT, two = STRBUF_INIT; struct strbuf buf = STRBUF_INIT; if (sha1) git_SHA1_Init(&ctx); while (!io->getline(&buf, io)) { if (is_cmarker(buf.buf, '<', marker_size)) { if (hunk != RR_CONTEXT) goto bad; hunk = RR_SIDE_1; } else if (is_cmarker(buf.buf, '|', marker_size)) { if (hunk != RR_SIDE_1) goto bad; hunk = RR_ORIGINAL; } else if (is_cmarker(buf.buf, '=', marker_size)) { if (hunk != RR_SIDE_1 && hunk != RR_ORIGINAL) goto bad; hunk = RR_SIDE_2; } else if (is_cmarker(buf.buf, '>', marker_size)) { if (hunk != RR_SIDE_2) goto bad; if (strbuf_cmp(&one, &two) > 0) strbuf_swap(&one, &two); hunk_no++; hunk = RR_CONTEXT; rerere_io_putconflict('<', marker_size, io); rerere_io_putmem(one.buf, one.len, io); rerere_io_putconflict('=', marker_size, io); rerere_io_putmem(two.buf, two.len, io); rerere_io_putconflict('>', marker_size, io); if (sha1) { git_SHA1_Update(&ctx, one.buf ? one.buf : "", one.len + 1); git_SHA1_Update(&ctx, two.buf ? two.buf : "", two.len + 1); } strbuf_reset(&one); strbuf_reset(&two); } else if (hunk == RR_SIDE_1) strbuf_addbuf(&one, &buf); else if (hunk == RR_ORIGINAL) ; /* discard */ else if (hunk == RR_SIDE_2) strbuf_addbuf(&two, &buf); else rerere_io_putstr(buf.buf, io); continue; bad: hunk = 99; /* force error exit */ break; } strbuf_release(&one); strbuf_release(&two); strbuf_release(&buf); if (sha1) git_SHA1_Final(sha1, &ctx); if (hunk != RR_CONTEXT) return -1; return hunk_no; } /* * Scan the path for conflicts, do the "handle_path()" thing above, and * return the number of conflict hunks found. */ static int handle_file(const char *path, unsigned char *sha1, const char *output) { int hunk_no = 0; struct rerere_io_file io; int marker_size = ll_merge_marker_size(path); memset(&io, 0, sizeof(io)); io.io.getline = rerere_file_getline; io.input = fopen(path, "r"); io.io.wrerror = 0; if (!io.input) return error_errno("Could not open %s", path); if (output) { io.io.output = fopen(output, "w"); if (!io.io.output) { error_errno("Could not write %s", output); fclose(io.input); return -1; } } hunk_no = handle_path(sha1, (struct rerere_io *)&io, marker_size); fclose(io.input); if (io.io.wrerror) error("There were errors while writing %s (%s)", path, strerror(io.io.wrerror)); if (io.io.output && fclose(io.io.output)) io.io.wrerror = error_errno("Failed to flush %s", path); if (hunk_no < 0) { if (output) unlink_or_warn(output); return error("Could not parse conflict hunks in %s", path); } if (io.io.wrerror) return -1; return hunk_no; } /* * Look at a cache entry at "i" and see if it is not conflicting, * conflicting and we are willing to handle, or conflicting and * we are unable to handle, and return the determination in *type. * Return the cache index to be looked at next, by skipping the * stages we have already looked at in this invocation of this * function. */ static int check_one_conflict(int i, int *type) { const struct cache_entry *e = active_cache[i]; if (!ce_stage(e)) { *type = RESOLVED; return i + 1; } *type = PUNTED; while (ce_stage(active_cache[i]) == 1) i++; /* Only handle regular files with both stages #2 and #3 */ if (i + 1 < active_nr) { const struct cache_entry *e2 = active_cache[i]; const struct cache_entry *e3 = active_cache[i + 1]; if (ce_stage(e2) == 2 && ce_stage(e3) == 3 && ce_same_name(e, e3) && S_ISREG(e2->ce_mode) && S_ISREG(e3->ce_mode)) *type = THREE_STAGED; } /* Skip the entries with the same name */ while (i < active_nr && ce_same_name(e, active_cache[i])) i++; return i; } /* * Scan the index and find paths that have conflicts that rerere can * handle, i.e. the ones that has both stages #2 and #3. * * NEEDSWORK: we do not record or replay a previous "resolve by * deletion" for a delete-modify conflict, as that is inherently risky * without knowing what modification is being discarded. The only * safe case, i.e. both side doing the deletion and modification that * are identical to the previous round, might want to be handled, * though. */ static int find_conflict(struct string_list *conflict) { int i; if (read_cache() < 0) return error("Could not read index"); for (i = 0; i < active_nr;) { int conflict_type; const struct cache_entry *e = active_cache[i]; i = check_one_conflict(i, &conflict_type); if (conflict_type == THREE_STAGED) string_list_insert(conflict, (const char *)e->name); } return 0; } /* * The merge_rr list is meant to hold outstanding conflicted paths * that rerere could handle. Abuse the list by adding other types of * entries to allow the caller to show "rerere remaining". * * - Conflicted paths that rerere does not handle are added * - Conflicted paths that have been resolved are marked as such * by storing RERERE_RESOLVED to .util field (where conflict ID * is expected to be stored). * * Do *not* write MERGE_RR file out after calling this function. * * NEEDSWORK: we may want to fix the caller that implements "rerere * remaining" to do this without abusing merge_rr. */ int rerere_remaining(struct string_list *merge_rr) { int i; if (setup_rerere(merge_rr, RERERE_READONLY)) return 0; if (read_cache() < 0) return error("Could not read index"); for (i = 0; i < active_nr;) { int conflict_type; const struct cache_entry *e = active_cache[i]; i = check_one_conflict(i, &conflict_type); if (conflict_type == PUNTED) string_list_insert(merge_rr, (const char *)e->name); else if (conflict_type == RESOLVED) { struct string_list_item *it; it = string_list_lookup(merge_rr, (const char *)e->name); if (it != NULL) { free_rerere_id(it); it->util = RERERE_RESOLVED; } } } return 0; } /* * Try using the given conflict resolution "ID" to see * if that recorded conflict resolves cleanly what we * got in the "cur". */ static int try_merge(const struct rerere_id *id, const char *path, mmfile_t *cur, mmbuffer_t *result) { int ret; mmfile_t base = {NULL, 0}, other = {NULL, 0}; if (read_mmfile(&base, rerere_path(id, "preimage")) || read_mmfile(&other, rerere_path(id, "postimage"))) ret = 1; else /* * A three-way merge. Note that this honors user-customizable * low-level merge driver settings. */ ret = ll_merge(result, path, &base, NULL, cur, "", &other, "", NULL); free(base.ptr); free(other.ptr); return ret; } /* * Find the conflict identified by "id"; the change between its * "preimage" (i.e. a previous contents with conflict markers) and its * "postimage" (i.e. the corresponding contents with conflicts * resolved) may apply cleanly to the contents stored in "path", i.e. * the conflict this time around. * * Returns 0 for successful replay of recorded resolution, or non-zero * for failure. */ static int merge(const struct rerere_id *id, const char *path) { FILE *f; int ret; mmfile_t cur = {NULL, 0}; mmbuffer_t result = {NULL, 0}; /* * Normalize the conflicts in path and write it out to * "thisimage" temporary file. */ if ((handle_file(path, NULL, rerere_path(id, "thisimage")) < 0) || read_mmfile(&cur, rerere_path(id, "thisimage"))) { ret = 1; goto out; } ret = try_merge(id, path, &cur, &result); if (ret) goto out; /* * A successful replay of recorded resolution. * Mark that "postimage" was used to help gc. */ if (utime(rerere_path(id, "postimage"), NULL) < 0) warning_errno("failed utime() on %s", rerere_path(id, "postimage")); /* Update "path" with the resolution */ f = fopen(path, "w"); if (!f) return error_errno("Could not open %s", path); if (fwrite(result.ptr, result.size, 1, f) != 1) error_errno("Could not write %s", path); if (fclose(f)) return error_errno("Writing %s failed", path); out: free(cur.ptr); free(result.ptr); return ret; } static struct lock_file index_lock; static void update_paths(struct string_list *update) { int i; hold_locked_index(&index_lock, LOCK_DIE_ON_ERROR); for (i = 0; i < update->nr; i++) { struct string_list_item *item = &update->items[i]; if (add_file_to_cache(item->string, 0)) exit(128); fprintf(stderr, "Staged '%s' using previous resolution.\n", item->string); } if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK | SKIP_IF_UNCHANGED)) die("Unable to write new index file"); } static void remove_variant(struct rerere_id *id) { unlink_or_warn(rerere_path(id, "postimage")); unlink_or_warn(rerere_path(id, "preimage")); id->collection->status[id->variant] = 0; } /* * The path indicated by rr_item may still have conflict for which we * have a recorded resolution, in which case replay it and optionally * update it. Or it may have been resolved by the user and we may * only have the preimage for that conflict, in which case the result * needs to be recorded as a resolution in a postimage file. */ static void do_rerere_one_path(struct string_list_item *rr_item, struct string_list *update) { const char *path = rr_item->string; struct rerere_id *id = rr_item->util; struct rerere_dir *rr_dir = id->collection; int variant; variant = id->variant; /* Has the user resolved it already? */ if (variant >= 0) { if (!handle_file(path, NULL, NULL)) { copy_file(rerere_path(id, "postimage"), path, 0666); id->collection->status[variant] |= RR_HAS_POSTIMAGE; fprintf(stderr, "Recorded resolution for '%s'.\n", path); free_rerere_id(rr_item); rr_item->util = NULL; return; } /* * There may be other variants that can cleanly * replay. Try them and update the variant number for * this one. */ } /* Does any existing resolution apply cleanly? */ for (variant = 0; variant < rr_dir->status_nr; variant++) { const int both = RR_HAS_PREIMAGE | RR_HAS_POSTIMAGE; struct rerere_id vid = *id; if ((rr_dir->status[variant] & both) != both) continue; vid.variant = variant; if (merge(&vid, path)) continue; /* failed to replay */ /* * If there already is a different variant that applies * cleanly, there is no point maintaining our own variant. */ if (0 <= id->variant && id->variant != variant) remove_variant(id); if (rerere_autoupdate) string_list_insert(update, path); else fprintf(stderr, "Resolved '%s' using previous resolution.\n", path); free_rerere_id(rr_item); rr_item->util = NULL; return; } /* None of the existing one applies; we need a new variant */ assign_variant(id); variant = id->variant; handle_file(path, NULL, rerere_path(id, "preimage")); if (id->collection->status[variant] & RR_HAS_POSTIMAGE) { const char *path = rerere_path(id, "postimage"); if (unlink(path)) die_errno("cannot unlink stray '%s'", path); id->collection->status[variant] &= ~RR_HAS_POSTIMAGE; } id->collection->status[variant] |= RR_HAS_PREIMAGE; fprintf(stderr, "Recorded preimage for '%s'\n", path); } static int do_plain_rerere(struct string_list *rr, int fd) { struct string_list conflict = STRING_LIST_INIT_DUP; struct string_list update = STRING_LIST_INIT_DUP; int i; find_conflict(&conflict); /* * MERGE_RR records paths with conflicts immediately after * merge failed. Some of the conflicted paths might have been * hand resolved in the working tree since then, but the * initial run would catch all and register their preimages. */ for (i = 0; i < conflict.nr; i++) { struct rerere_id *id; unsigned char sha1[20]; const char *path = conflict.items[i].string; int ret; if (string_list_has_string(rr, path)) continue; /* * Ask handle_file() to scan and assign a * conflict ID. No need to write anything out * yet. */ ret = handle_file(path, sha1, NULL); if (ret < 1) continue; id = new_rerere_id(sha1); string_list_insert(rr, path)->util = id; /* Ensure that the directory exists. */ mkdir_in_gitdir(rerere_path(id, NULL)); } for (i = 0; i < rr->nr; i++) do_rerere_one_path(&rr->items[i], &update); if (update.nr) update_paths(&update); return write_rr(rr, fd); } static void git_rerere_config(void) { git_config_get_bool("rerere.enabled", &rerere_enabled); git_config_get_bool("rerere.autoupdate", &rerere_autoupdate); git_config(git_default_config, NULL); } static GIT_PATH_FUNC(git_path_rr_cache, "rr-cache") static int is_rerere_enabled(void) { int rr_cache_exists; if (!rerere_enabled) return 0; rr_cache_exists = is_directory(git_path_rr_cache()); if (rerere_enabled < 0) return rr_cache_exists; if (!rr_cache_exists && mkdir_in_gitdir(git_path_rr_cache())) die("Could not create directory %s", git_path_rr_cache()); return 1; } int setup_rerere(struct string_list *merge_rr, int flags) { int fd; git_rerere_config(); if (!is_rerere_enabled()) return -1; if (flags & (RERERE_AUTOUPDATE|RERERE_NOAUTOUPDATE)) rerere_autoupdate = !!(flags & RERERE_AUTOUPDATE); if (flags & RERERE_READONLY) fd = 0; else fd = hold_lock_file_for_update(&write_lock, git_path_merge_rr(the_repository), LOCK_DIE_ON_ERROR); read_rr(merge_rr); return fd; } /* * The main entry point that is called internally from codepaths that * perform mergy operations, possibly leaving conflicted index entries * and working tree files. */ int rerere(int flags) { struct string_list merge_rr = STRING_LIST_INIT_DUP; int fd, status; fd = setup_rerere(&merge_rr, flags); if (fd < 0) return 0; status = do_plain_rerere(&merge_rr, fd); free_rerere_dirs(); return status; } /* * Subclass of rerere_io that reads from an in-core buffer that is a * strbuf */ struct rerere_io_mem { struct rerere_io io; struct strbuf input; }; /* * ... and its getline() method implementation */ static int rerere_mem_getline(struct strbuf *sb, struct rerere_io *io_) { struct rerere_io_mem *io = (struct rerere_io_mem *)io_; char *ep; size_t len; strbuf_release(sb); if (!io->input.len) return -1; ep = memchr(io->input.buf, '\n', io->input.len); if (!ep) ep = io->input.buf + io->input.len; else if (*ep == '\n') ep++; len = ep - io->input.buf; strbuf_add(sb, io->input.buf, len); strbuf_remove(&io->input, 0, len); return 0; } static int handle_cache(const char *path, unsigned char *sha1, const char *output) { mmfile_t mmfile[3] = {{NULL}}; mmbuffer_t result = {NULL, 0}; const struct cache_entry *ce; int pos, len, i, hunk_no; struct rerere_io_mem io; int marker_size = ll_merge_marker_size(path); /* * Reproduce the conflicted merge in-core */ len = strlen(path); pos = cache_name_pos(path, len); if (0 <= pos) return -1; pos = -pos - 1; while (pos < active_nr) { enum object_type type; unsigned long size; ce = active_cache[pos++]; if (ce_namelen(ce) != len || memcmp(ce->name, path, len)) break; i = ce_stage(ce) - 1; if (!mmfile[i].ptr) { mmfile[i].ptr = read_object_file(&ce->oid, &type, &size); mmfile[i].size = size; } } for (i = 0; i < 3; i++) if (!mmfile[i].ptr && !mmfile[i].size) mmfile[i].ptr = xstrdup(""); /* * NEEDSWORK: handle conflicts from merges with * merge.renormalize set, too? */ ll_merge(&result, path, &mmfile[0], NULL, &mmfile[1], "ours", &mmfile[2], "theirs", NULL); for (i = 0; i < 3; i++) free(mmfile[i].ptr); memset(&io, 0, sizeof(io)); io.io.getline = rerere_mem_getline; if (output) io.io.output = fopen(output, "w"); else io.io.output = NULL; strbuf_init(&io.input, 0); strbuf_attach(&io.input, result.ptr, result.size, result.size); /* * Grab the conflict ID and optionally write the original * contents with conflict markers out. */ hunk_no = handle_path(sha1, (struct rerere_io *)&io, marker_size); strbuf_release(&io.input); if (io.io.output) fclose(io.io.output); return hunk_no; } static int rerere_forget_one_path(const char *path, struct string_list *rr) { const char *filename; struct rerere_id *id; unsigned char sha1[20]; int ret; struct string_list_item *item; /* * Recreate the original conflict from the stages in the * index and compute the conflict ID */ ret = handle_cache(path, sha1, NULL); if (ret < 1) return error("Could not parse conflict hunks in '%s'", path); /* Nuke the recorded resolution for the conflict */ id = new_rerere_id(sha1); for (id->variant = 0; id->variant < id->collection->status_nr; id->variant++) { mmfile_t cur = { NULL, 0 }; mmbuffer_t result = {NULL, 0}; int cleanly_resolved; if (!has_rerere_resolution(id)) continue; handle_cache(path, sha1, rerere_path(id, "thisimage")); if (read_mmfile(&cur, rerere_path(id, "thisimage"))) { free(cur.ptr); error("Failed to update conflicted state in '%s'", path); goto fail_exit; } cleanly_resolved = !try_merge(id, path, &cur, &result); free(result.ptr); free(cur.ptr); if (cleanly_resolved) break; } if (id->collection->status_nr <= id->variant) { error("no remembered resolution for '%s'", path); goto fail_exit; } filename = rerere_path(id, "postimage"); if (unlink(filename)) { if (errno == ENOENT) error("no remembered resolution for %s", path); else error_errno("cannot unlink %s", filename); goto fail_exit; } /* * Update the preimage so that the user can resolve the * conflict in the working tree, run us again to record * the postimage. */ handle_cache(path, sha1, rerere_path(id, "preimage")); fprintf(stderr, "Updated preimage for '%s'\n", path); /* * And remember that we can record resolution for this * conflict when the user is done. */ item = string_list_insert(rr, path); free_rerere_id(item); item->util = id; fprintf(stderr, "Forgot resolution for %s\n", path); return 0; fail_exit: free(id); return -1; } int rerere_forget(struct pathspec *pathspec) { int i, fd; struct string_list conflict = STRING_LIST_INIT_DUP; struct string_list merge_rr = STRING_LIST_INIT_DUP; if (read_cache() < 0) return error("Could not read index"); fd = setup_rerere(&merge_rr, RERERE_NOAUTOUPDATE); if (fd < 0) return 0; /* * The paths may have been resolved (incorrectly); * recover the original conflicted state and then * find the conflicted paths. */ unmerge_cache(pathspec); find_conflict(&conflict); for (i = 0; i < conflict.nr; i++) { struct string_list_item *it = &conflict.items[i]; if (!match_pathspec(pathspec, it->string, strlen(it->string), 0, NULL, 0)) continue; rerere_forget_one_path(it->string, &merge_rr); } return write_rr(&merge_rr, fd); } /* * Garbage collection support */ static timestamp_t rerere_created_at(struct rerere_id *id) { struct stat st; return stat(rerere_path(id, "preimage"), &st) ? (time_t) 0 : st.st_mtime; } static timestamp_t rerere_last_used_at(struct rerere_id *id) { struct stat st; return stat(rerere_path(id, "postimage"), &st) ? (time_t) 0 : st.st_mtime; } /* * Remove the recorded resolution for a given conflict ID */ static void unlink_rr_item(struct rerere_id *id) { unlink_or_warn(rerere_path(id, "thisimage")); remove_variant(id); id->collection->status[id->variant] = 0; } static void prune_one(struct rerere_id *id, timestamp_t cutoff_resolve, timestamp_t cutoff_noresolve) { timestamp_t then; timestamp_t cutoff; then = rerere_last_used_at(id); if (then) cutoff = cutoff_resolve; else { then = rerere_created_at(id); if (!then) return; cutoff = cutoff_noresolve; } if (then < cutoff) unlink_rr_item(id); } void rerere_gc(struct string_list *rr) { struct string_list to_remove = STRING_LIST_INIT_DUP; DIR *dir; struct dirent *e; int i; timestamp_t now = time(NULL); timestamp_t cutoff_noresolve = now - 15 * 86400; timestamp_t cutoff_resolve = now - 60 * 86400; if (setup_rerere(rr, 0) < 0) return; git_config_get_expiry_in_days("gc.rerereresolved", &cutoff_resolve, now); git_config_get_expiry_in_days("gc.rerereunresolved", &cutoff_noresolve, now); git_config(git_default_config, NULL); dir = opendir(git_path("rr-cache")); if (!dir) die_errno("unable to open rr-cache directory"); /* Collect stale conflict IDs ... */ while ((e = readdir(dir))) { struct rerere_dir *rr_dir; struct rerere_id id; int now_empty; if (is_dot_or_dotdot(e->d_name)) continue; rr_dir = find_rerere_dir(e->d_name); if (!rr_dir) continue; /* or should we remove e->d_name? */ now_empty = 1; for (id.variant = 0, id.collection = rr_dir; id.variant < id.collection->status_nr; id.variant++) { prune_one(&id, cutoff_resolve, cutoff_noresolve); if (id.collection->status[id.variant]) now_empty = 0; } if (now_empty) string_list_append(&to_remove, e->d_name); } closedir(dir); /* ... and then remove the empty directories */ for (i = 0; i < to_remove.nr; i++) rmdir(git_path("rr-cache/%s", to_remove.items[i].string)); string_list_clear(&to_remove, 0); rollback_lock_file(&write_lock); } /* * During a conflict resolution, after "rerere" recorded the * preimages, abandon them if the user did not resolve them or * record their resolutions. And drop $GIT_DIR/MERGE_RR. * * NEEDSWORK: shouldn't we be calling this from "reset --hard"? */ void rerere_clear(struct string_list *merge_rr) { int i; if (setup_rerere(merge_rr, 0) < 0) return; for (i = 0; i < merge_rr->nr; i++) { struct rerere_id *id = merge_rr->items[i].util; if (!has_rerere_resolution(id)) { unlink_rr_item(id); rmdir(rerere_path(id, NULL)); } } unlink_or_warn(git_path_merge_rr(the_repository)); rollback_lock_file(&write_lock); }