| #include "cache.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 "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(rerere_dir); |
| rerere_dir_nr = rerere_dir_alloc = 0; |
| rerere_dir = NULL; |
| } |
| |
| 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++; |
| memmove(rerere_dir + pos + 1, rerere_dir + pos, |
| (rerere_dir_nr - pos - 1) * sizeof(*rerere_dir)); |
| 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(git_path_merge_rr(), "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) != buf.len) |
| 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("Could not open %s", path); |
| |
| if (output) { |
| io.io.output = fopen(output, "w"); |
| if (!io.io.output) { |
| fclose(io.input); |
| return error("Could not write %s", output); |
| } |
| } |
| |
| 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, 1); |
| |
| 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 (active_cache_changed) { |
| if (write_locked_index(&the_index, &index_lock, COMMIT_LOCK)) |
| die("Unable to write new index file"); |
| } else |
| rollback_lock_file(&index_lock); |
| } |
| |
| 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(), |
| 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_sha1_file(ce->oid.hash, &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 time_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 time_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, time_t now, |
| int cutoff_resolve, int cutoff_noresolve) |
| { |
| time_t then; |
| int 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 < now - cutoff * 86400) |
| 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; |
| time_t now = time(NULL); |
| int cutoff_noresolve = 15; |
| int cutoff_resolve = 60; |
| |
| if (setup_rerere(rr, 0) < 0) |
| return; |
| |
| git_config_get_int("gc.rerereresolved", &cutoff_resolve); |
| git_config_get_int("gc.rerereunresolved", &cutoff_noresolve); |
| 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, now, 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()); |
| rollback_lock_file(&write_lock); |
| } |