mergetool: Provide an empty file when needed
[gitweb.git] / rerere.c
index d1d3e753955146cadfaf6da274487a4a369f0521..dcb525a4d03faeba53d108d2e175a6d04f99d160 100644 (file)
--- a/rerere.c
+++ b/rerere.c
@@ -7,6 +7,11 @@
 #include "ll-merge.h"
 #include "attr.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;
 
@@ -42,11 +47,17 @@ static void read_rr(struct string_list *rr)
                name = xstrdup(buf);
                if (fgetc(in) != '\t')
                        die("corrupt MERGE_RR");
-               for (i = 0; i < sizeof(buf) && (buf[i] = fgetc(in)); i++)
-                       ; /* do nothing */
+               for (i = 0; i < sizeof(buf); i++) {
+                       int c = fgetc(in);
+                       if (c < 0)
+                               die("corrupt MERGE_RR");
+                       buf[i] = c;
+                       if (c == 0)
+                                break;
+               }
                if (i == sizeof(buf))
                        die("filename too long");
-               string_list_insert(buf, rr)->util = name;
+               string_list_insert(rr, buf)->util = name;
        }
        fclose(in);
 }
@@ -153,7 +164,7 @@ static int handle_path(unsigned char *sha1, struct rerere_io *io, int marker_siz
        git_SHA_CTX ctx;
        int hunk_no = 0;
        enum {
-               RR_CONTEXT = 0, RR_SIDE_1, RR_SIDE_2, RR_ORIGINAL,
+               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;
@@ -319,9 +330,13 @@ static int handle_cache(const char *path, unsigned char *sha1, const char *outpu
                if (!mmfile[i].ptr && !mmfile[i].size)
                        mmfile[i].ptr = xstrdup("");
        }
-       ll_merge(&result, path, &mmfile[0],
+       /*
+        * NEEDSWORK: handle conflicts from merges with
+        * merge.renormalize set, too
+        */
+       ll_merge(&result, path, &mmfile[0], NULL,
                 &mmfile[1], "ours",
-                &mmfile[2], "theirs", 0);
+                &mmfile[2], "theirs", NULL);
        for (i = 0; i < 3; i++)
                free(mmfile[i].ptr);
 
@@ -341,21 +356,74 @@ static int handle_cache(const char *path, unsigned char *sha1, const char *outpu
        return hunk_no;
 }
 
-static int find_conflict(struct string_list *conflict)
+static int check_one_conflict(int i, int *type)
 {
-       int i;
-       if (read_cache() < 0)
-               return error("Could not read index");
-       for (i = 0; i+1 < active_nr; i++) {
+       struct cache_entry *e = active_cache[i];
+
+       if (!ce_stage(e)) {
+               *type = RESOLVED;
+               return i + 1;
+       }
+
+       *type = PUNTED;
+       if (ce_stage(e) == 1) {
+               if (active_nr <= ++i)
+                       return i + 1;
+       }
+
+       /* Only handle regular files with both stages #2 and #3 */
+       if (i + 1 < active_nr) {
                struct cache_entry *e2 = active_cache[i];
-               struct cache_entry *e3 = active_cache[i+1];
+               struct cache_entry *e3 = active_cache[i + 1];
                if (ce_stage(e2) == 2 &&
                    ce_stage(e3) == 3 &&
-                   ce_same_name(e2, e3) &&
+                   ce_same_name(e, e3) &&
                    S_ISREG(e2->ce_mode) &&
-                   S_ISREG(e3->ce_mode)) {
-                       string_list_insert((const char *)e2->name, conflict);
-                       i++; /* skip over both #2 and #3 */
+                   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;
+}
+
+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;
+               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;
+}
+
+int rerere_remaining(struct string_list *merge_rr)
+{
+       int i;
+       if (read_cache() < 0)
+               return error("Could not read index");
+
+       for (i = 0; i < active_nr;) {
+               int conflict_type;
+               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(it->util);
+                               it->util = RERERE_RESOLVED;
+                       }
                }
        }
        return 0;
@@ -364,7 +432,7 @@ static int find_conflict(struct string_list *conflict)
 static int merge(const char *name, const char *path)
 {
        int ret;
-       mmfile_t cur, base, other;
+       mmfile_t cur = {NULL, 0}, base = {NULL, 0}, other = {NULL, 0};
        mmbuffer_t result = {NULL, 0};
 
        if (handle_file(path, NULL, rerere_path(name, "thisimage")) < 0)
@@ -372,11 +440,19 @@ static int merge(const char *name, const char *path)
 
        if (read_mmfile(&cur, rerere_path(name, "thisimage")) ||
                        read_mmfile(&base, rerere_path(name, "preimage")) ||
-                       read_mmfile(&other, rerere_path(name, "postimage")))
-               return 1;
-       ret = ll_merge(&result, path, &base, &cur, "", &other, "", 0);
+                       read_mmfile(&other, rerere_path(name, "postimage"))) {
+               ret = 1;
+               goto out;
+       }
+       ret = ll_merge(&result, path, &base, NULL, &cur, "", &other, "", NULL);
        if (!ret) {
-               FILE *f = fopen(path, "w");
+               FILE *f;
+
+               if (utime(rerere_path(name, "postimage"), NULL) < 0)
+                       warning("failed utime() on %s: %s",
+                                       rerere_path(name, "postimage"),
+                                       strerror(errno));
+               f = fopen(path, "w");
                if (!f)
                        return error("Could not open %s: %s", path,
                                     strerror(errno));
@@ -387,6 +463,7 @@ static int merge(const char *name, const char *path)
                                     strerror(errno));
        }
 
+out:
        free(cur.ptr);
        free(base.ptr);
        free(other.ptr);
@@ -423,8 +500,8 @@ static int update_paths(struct string_list *update)
 
 static int do_plain_rerere(struct string_list *rr, int fd)
 {
-       struct string_list conflict = { NULL, 0, 0, 1 };
-       struct string_list update = { NULL, 0, 0, 1 };
+       struct string_list conflict = STRING_LIST_INIT_DUP;
+       struct string_list update = STRING_LIST_INIT_DUP;
        int i;
 
        find_conflict(&conflict);
@@ -446,7 +523,7 @@ static int do_plain_rerere(struct string_list *rr, int fd)
                        if (ret < 1)
                                continue;
                        hex = xstrdup(sha1_to_hex(sha1));
-                       string_list_insert(path, rr)->util = hex;
+                       string_list_insert(rr, path)->util = hex;
                        if (mkdir(git_path("rr-cache/%s", hex), 0755))
                                continue;
                        handle_file(path, NULL, rerere_path(hex, "preimage"));
@@ -468,7 +545,7 @@ static int do_plain_rerere(struct string_list *rr, int fd)
                if (has_rerere_resolution(name)) {
                        if (!merge(name, path)) {
                                if (rerere_autoupdate)
-                                       string_list_insert(path, &update);
+                                       string_list_insert(&update, path);
                                fprintf(stderr,
                                        "%s '%s' using previous resolution.\n",
                                        rerere_autoupdate
@@ -519,8 +596,7 @@ static int is_rerere_enabled(void)
        if (rerere_enabled < 0)
                return rr_cache_exists;
 
-       if (!rr_cache_exists &&
-           (mkdir(rr_cache, 0777) || adjust_shared_perm(rr_cache)))
+       if (!rr_cache_exists && mkdir_in_gitdir(rr_cache))
                die("Could not create directory %s", rr_cache);
        return 1;
 }
@@ -544,7 +620,7 @@ int setup_rerere(struct string_list *merge_rr, int flags)
 
 int rerere(int flags)
 {
-       struct string_list merge_rr = { NULL, 0, 0, 1 };
+       struct string_list merge_rr = STRING_LIST_INIT_DUP;
        int fd;
 
        fd = setup_rerere(&merge_rr, flags);
@@ -574,7 +650,7 @@ static int rerere_forget_one_path(const char *path, struct string_list *rr)
        fprintf(stderr, "Updated preimage for '%s'\n", path);
 
 
-       string_list_insert(path, rr)->util = hex;
+       string_list_insert(rr, path)->util = hex;
        fprintf(stderr, "Forgot resolution for %s\n", path);
        return 0;
 }
@@ -582,8 +658,8 @@ static int rerere_forget_one_path(const char *path, struct string_list *rr)
 int rerere_forget(const char **pathspec)
 {
        int i, fd;
-       struct string_list conflict = { NULL, 0, 0, 1 };
-       struct string_list merge_rr = { NULL, 0, 0, 1 };
+       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");
@@ -601,3 +677,88 @@ int rerere_forget(const char **pathspec)
        }
        return write_rr(&merge_rr, fd);
 }
+
+static time_t rerere_created_at(const char *name)
+{
+       struct stat st;
+       return stat(rerere_path(name, "preimage"), &st) ? (time_t) 0 : st.st_mtime;
+}
+
+static time_t rerere_last_used_at(const char *name)
+{
+       struct stat st;
+       return stat(rerere_path(name, "postimage"), &st) ? (time_t) 0 : st.st_mtime;
+}
+
+static void unlink_rr_item(const char *name)
+{
+       unlink(rerere_path(name, "thisimage"));
+       unlink(rerere_path(name, "preimage"));
+       unlink(rerere_path(name, "postimage"));
+       rmdir(git_path("rr-cache/%s", name));
+}
+
+struct rerere_gc_config_cb {
+       int cutoff_noresolve;
+       int cutoff_resolve;
+};
+
+static int git_rerere_gc_config(const char *var, const char *value, void *cb)
+{
+       struct rerere_gc_config_cb *cf = cb;
+
+       if (!strcmp(var, "gc.rerereresolved"))
+               cf->cutoff_resolve = git_config_int(var, value);
+       else if (!strcmp(var, "gc.rerereunresolved"))
+               cf->cutoff_noresolve = git_config_int(var, value);
+       else
+               return git_default_config(var, value, cb);
+       return 0;
+}
+
+void rerere_gc(struct string_list *rr)
+{
+       struct string_list to_remove = STRING_LIST_INIT_DUP;
+       DIR *dir;
+       struct dirent *e;
+       int i, cutoff;
+       time_t now = time(NULL), then;
+       struct rerere_gc_config_cb cf = { 15, 60 };
+
+       git_config(git_rerere_gc_config, &cf);
+       dir = opendir(git_path("rr-cache"));
+       if (!dir)
+               die_errno("unable to open rr-cache directory");
+       while ((e = readdir(dir))) {
+               if (is_dot_or_dotdot(e->d_name))
+                       continue;
+
+               then = rerere_last_used_at(e->d_name);
+               if (then) {
+                       cutoff = cf.cutoff_resolve;
+               } else {
+                       then = rerere_created_at(e->d_name);
+                       if (!then)
+                               continue;
+                       cutoff = cf.cutoff_noresolve;
+               }
+               if (then < now - cutoff * 86400)
+                       string_list_append(&to_remove, e->d_name);
+       }
+       closedir(dir);
+       for (i = 0; i < to_remove.nr; i++)
+               unlink_rr_item(to_remove.items[i].string);
+       string_list_clear(&to_remove, 0);
+}
+
+void rerere_clear(struct string_list *merge_rr)
+{
+       int i;
+
+       for (i = 0; i < merge_rr->nr; i++) {
+               const char *name = (const char *)merge_rr->items[i].util;
+               if (!has_rerere_resolution(name))
+                       unlink_rr_item(name);
+       }
+       unlink_or_warn(git_path("MERGE_RR"));
+}