#include "builtin.h" #include "cache.h" #include "path-list.h" #include "xdiff/xdiff.h" #include "xdiff-interface.h" #include <time.h> static const char git_rerere_usage[] = "git-rerere [clear | status | diff | gc]"; /* these values are days */ static int cutoff_noresolve = 15; static int cutoff_resolve = 60; /* if rerere_enabled == -1, fall back to detection of .git/rr-cache */ static int rerere_enabled = -1; static char *merge_rr_path; static const char *rr_path(const char *name, const char *file) { return git_path("rr-cache/%s/%s", name, file); } static void read_rr(struct path_list *rr) { unsigned char sha1[20]; char buf[PATH_MAX]; FILE *in = fopen(merge_rr_path, "r"); if (!in) return; while (fread(buf, 40, 1, in) == 1) { int i; char *name; if (get_sha1_hex(buf, sha1)) die("corrupt MERGE_RR"); buf[40] = '\0'; name = xstrdup(buf); if (fgetc(in) != '\t') die("corrupt MERGE_RR"); for (i = 0; i < sizeof(buf) && (buf[i] = fgetc(in)); i++) ; /* do nothing */ if (i == sizeof(buf)) die("filename too long"); path_list_insert(buf, rr)->util = xstrdup(name); } fclose(in); } static struct lock_file write_lock; static int write_rr(struct path_list *rr, int out_fd) { int i; for (i = 0; i < rr->nr; i++) { const char *path = rr->items[i].path; int length = strlen(path) + 1; if (write_in_full(out_fd, rr->items[i].util, 40) != 40 || write_in_full(out_fd, "\t", 1) != 1 || write_in_full(out_fd, path, length) != length) die("unable to write rerere record"); } if (close(out_fd) != 0) die("unable to write rerere record"); return commit_lock_file(&write_lock); } static int handle_file(const char *path, unsigned char *sha1, const char *output) { SHA_CTX ctx; char buf[1024]; int hunk = 0, hunk_no = 0; struct strbuf one, two; FILE *f = fopen(path, "r"); FILE *out = NULL; if (!f) return error("Could not open %s", path); if (output) { out = fopen(output, "w"); if (!out) { fclose(f); return error("Could not write %s", output); } } if (sha1) SHA1_Init(&ctx); strbuf_init(&one, 0); strbuf_init(&two, 0); while (fgets(buf, sizeof(buf), f)) { if (!prefixcmp(buf, "<<<<<<< ")) hunk = 1; else if (!prefixcmp(buf, "=======")) hunk = 2; else if (!prefixcmp(buf, ">>>>>>> ")) { int cmp = strbuf_cmp(&one, &two); hunk_no++; hunk = 0; if (cmp > 0) { strbuf_swap(&one, &two); } if (out) { fputs("<<<<<<<\n", out); fwrite(one.buf, one.len, 1, out); fputs("=======\n", out); fwrite(two.buf, two.len, 1, out); fputs(">>>>>>>\n", out); } if (sha1) { SHA1_Update(&ctx, one.buf ? one.buf : "", one.len + 1); SHA1_Update(&ctx, two.buf ? two.buf : "", two.len + 1); } strbuf_reset(&one); strbuf_reset(&two); } else if (hunk == 1) strbuf_addstr(&one, buf); else if (hunk == 2) strbuf_addstr(&two, buf); else if (out) fputs(buf, out); } strbuf_release(&one); strbuf_release(&two); fclose(f); if (out) fclose(out); if (sha1) SHA1_Final(sha1, &ctx); return hunk_no; } static int find_conflict(struct path_list *conflict) { int i; if (read_cache() < 0) return error("Could not read index"); for (i = 0; i+1 < active_nr; i++) { struct cache_entry *e2 = active_cache[i]; struct cache_entry *e3 = active_cache[i+1]; if (ce_stage(e2) == 2 && ce_stage(e3) == 3 && ce_same_name(e2, e3) && S_ISREG(ntohl(e2->ce_mode)) && S_ISREG(ntohl(e3->ce_mode))) { path_list_insert((const char *)e2->name, conflict); i++; /* skip over both #2 and #3 */ } } return 0; } static int merge(const char *name, const char *path) { int ret; mmfile_t cur, base, other; mmbuffer_t result = {NULL, 0}; xpparam_t xpp = {XDF_NEED_MINIMAL}; if (handle_file(path, NULL, rr_path(name, "thisimage")) < 0) return 1; if (read_mmfile(&cur, rr_path(name, "thisimage")) || read_mmfile(&base, rr_path(name, "preimage")) || read_mmfile(&other, rr_path(name, "postimage"))) return 1; ret = xdl_merge(&base, &cur, "", &other, "", &xpp, XDL_MERGE_ZEALOUS, &result); if (!ret) { FILE *f = fopen(path, "w"); if (!f) return error("Could not write to %s", path); fwrite(result.ptr, result.size, 1, f); fclose(f); } free(cur.ptr); free(base.ptr); free(other.ptr); free(result.ptr); return ret; } static void unlink_rr_item(const char *name) { unlink(rr_path(name, "thisimage")); unlink(rr_path(name, "preimage")); unlink(rr_path(name, "postimage")); rmdir(git_path("rr-cache/%s", name)); } static void garbage_collect(struct path_list *rr) { struct path_list to_remove = { NULL, 0, 0, 1 }; char buf[1024]; DIR *dir; struct dirent *e; int len, i, cutoff; time_t now = time(NULL), then; strlcpy(buf, git_path("rr-cache"), sizeof(buf)); len = strlen(buf); dir = opendir(buf); strcpy(buf + len++, "/"); while ((e = readdir(dir))) { const char *name = e->d_name; struct stat st; if (name[0] == '.' && (name[1] == '\0' || (name[1] == '.' && name[2] == '\0'))) continue; i = snprintf(buf + len, sizeof(buf) - len, "%s", name); strlcpy(buf + len + i, "/preimage", sizeof(buf) - len - i); if (stat(buf, &st)) continue; then = st.st_mtime; strlcpy(buf + len + i, "/postimage", sizeof(buf) - len - i); cutoff = stat(buf, &st) ? cutoff_noresolve : cutoff_resolve; if (then < now - cutoff * 86400) { buf[len + i] = '\0'; path_list_insert(xstrdup(name), &to_remove); } } for (i = 0; i < to_remove.nr; i++) unlink_rr_item(to_remove.items[i].path); path_list_clear(&to_remove, 0); } static int outf(void *dummy, mmbuffer_t *ptr, int nbuf) { int i; for (i = 0; i < nbuf; i++) if (write_in_full(1, ptr[i].ptr, ptr[i].size) != ptr[i].size) return -1; return 0; } static int diff_two(const char *file1, const char *label1, const char *file2, const char *label2) { xpparam_t xpp; xdemitconf_t xecfg; xdemitcb_t ecb; mmfile_t minus, plus; if (read_mmfile(&minus, file1) || read_mmfile(&plus, file2)) return 1; printf("--- a/%s\n+++ b/%s\n", label1, label2); fflush(stdout); xpp.flags = XDF_NEED_MINIMAL; memset(&xecfg, 0, sizeof(xecfg)); xecfg.ctxlen = 3; ecb.outf = outf; xdl_diff(&minus, &plus, &xpp, &xecfg, &ecb); free(minus.ptr); free(plus.ptr); return 0; } static int copy_file(const char *src, const char *dest) { FILE *in, *out; char buffer[32768]; int count; if (!(in = fopen(src, "r"))) return error("Could not open %s", src); if (!(out = fopen(dest, "w"))) return error("Could not open %s", dest); while ((count = fread(buffer, 1, sizeof(buffer), in))) fwrite(buffer, 1, count, out); fclose(in); fclose(out); return 0; } static int do_plain_rerere(struct path_list *rr, int fd) { struct path_list conflict = { NULL, 0, 0, 1 }; 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++) { const char *path = conflict.items[i].path; if (!path_list_has_path(rr, path)) { unsigned char sha1[20]; char *hex; int ret; ret = handle_file(path, sha1, NULL); if (ret < 1) continue; hex = xstrdup(sha1_to_hex(sha1)); path_list_insert(path, rr)->util = hex; if (mkdir(git_path("rr-cache/%s", hex), 0755)) continue;; handle_file(path, NULL, rr_path(hex, "preimage")); fprintf(stderr, "Recorded preimage for '%s'\n", path); } } /* * Now some of the paths that had conflicts earlier might have been * hand resolved. Others may be similar to a conflict already that * was resolved before. */ for (i = 0; i < rr->nr; i++) { struct stat st; int ret; const char *path = rr->items[i].path; const char *name = (const char *)rr->items[i].util; if (!stat(rr_path(name, "preimage"), &st) && !stat(rr_path(name, "postimage"), &st)) { if (!merge(name, path)) { fprintf(stderr, "Resolved '%s' using " "previous resolution.\n", path); goto tail_optimization; } } /* Let's see if we have resolved it. */ ret = handle_file(path, NULL, NULL); if (ret) continue; fprintf(stderr, "Recorded resolution for '%s'.\n", path); copy_file(path, rr_path(name, "postimage")); tail_optimization: if (i < rr->nr - 1) memmove(rr->items + i, rr->items + i + 1, sizeof(rr->items[0]) * (rr->nr - i - 1)); rr->nr--; i--; } return write_rr(rr, fd); } static int git_rerere_config(const char *var, const char *value) { if (!strcmp(var, "gc.rerereresolved")) cutoff_resolve = git_config_int(var, value); else if (!strcmp(var, "gc.rerereunresolved")) cutoff_noresolve = git_config_int(var, value); else if (!strcmp(var, "rerere.enabled")) rerere_enabled = git_config_bool(var, value); else return git_default_config(var, value); return 0; } static int is_rerere_enabled(void) { struct stat st; const char *rr_cache; int rr_cache_exists; if (!rerere_enabled) return 0; rr_cache = git_path("rr-cache"); rr_cache_exists = !stat(rr_cache, &st) && S_ISDIR(st.st_mode); if (rerere_enabled < 0) return rr_cache_exists; if (!rr_cache_exists && (mkdir(rr_cache, 0777) || adjust_shared_perm(rr_cache))) die("Could not create directory %s", rr_cache); return 1; } static int setup_rerere(struct path_list *merge_rr) { int fd; git_config(git_rerere_config); if (!is_rerere_enabled()) return -1; merge_rr_path = xstrdup(git_path("rr-cache/MERGE_RR")); fd = hold_lock_file_for_update(&write_lock, merge_rr_path, 1); read_rr(merge_rr); return fd; } int rerere(void) { struct path_list merge_rr = { NULL, 0, 0, 1 }; int fd; fd = setup_rerere(&merge_rr); if (fd < 0) return 0; return do_plain_rerere(&merge_rr, fd); } int cmd_rerere(int argc, const char **argv, const char *prefix) { struct path_list merge_rr = { NULL, 0, 0, 1 }; int i, fd; fd = setup_rerere(&merge_rr); if (fd < 0) return 0; if (argc < 2) return do_plain_rerere(&merge_rr, fd); else if (!strcmp(argv[1], "clear")) { for (i = 0; i < merge_rr.nr; i++) { struct stat st; const char *name = (const char *)merge_rr.items[i].util; if (!stat(git_path("rr-cache/%s", name), &st) && S_ISDIR(st.st_mode) && stat(rr_path(name, "postimage"), &st)) unlink_rr_item(name); } unlink(merge_rr_path); } else if (!strcmp(argv[1], "gc")) garbage_collect(&merge_rr); else if (!strcmp(argv[1], "status")) for (i = 0; i < merge_rr.nr; i++) printf("%s\n", merge_rr.items[i].path); else if (!strcmp(argv[1], "diff")) for (i = 0; i < merge_rr.nr; i++) { const char *path = merge_rr.items[i].path; const char *name = (const char *)merge_rr.items[i].util; diff_two(rr_path(name, "preimage"), path, path, path); } else usage(git_rerere_usage); path_list_clear(&merge_rr, 1); return 0; }