Optimize peel_ref for the current ref of a for_each_ref callback
[gitweb.git] / builtin-name-rev.c
index 61eba343ab781341a0baf127b323508a0c2af332..f22c8b5f5da0031657f10ddb827d33a07056e3a5 100644 (file)
@@ -3,22 +3,23 @@
 #include "commit.h"
 #include "tag.h"
 #include "refs.h"
+#include "parse-options.h"
 
 #define CUTOFF_DATE_SLOP 86400 /* one day */
 
-static const char name_rev_usage[] =
-       "git-name-rev [--tags | --refs=<pattern>] ( --all | --stdin | committish [committish...] )\n";
-
 typedef struct rev_name {
        const char *tip_name;
-       int merge_traversals;
        int generation;
+       int distance;
 } rev_name;
 
 static long cutoff = LONG_MAX;
 
+/* How many generations are maximally preferred over _one_ merge traversal? */
+#define MERGE_TRAVERSAL_WEIGHT 65535
+
 static void name_rev(struct commit *commit,
-               const char *tip_name, int merge_traversals, int generation,
+               const char *tip_name, int generation, int distance,
                int deref)
 {
        struct rev_name *name = (struct rev_name *)commit->util;
@@ -45,13 +46,11 @@ static void name_rev(struct commit *commit,
                name = xmalloc(sizeof(rev_name));
                commit->util = name;
                goto copy_data;
-       } else if (name->merge_traversals > merge_traversals ||
-                       (name->merge_traversals == merge_traversals &&
-                        name->generation > generation)) {
+       } else if (name->distance > distance) {
 copy_data:
                name->tip_name = tip_name;
-               name->merge_traversals = merge_traversals;
                name->generation = generation;
+               name->distance = distance;
        } else
                return;
 
@@ -74,11 +73,11 @@ static void name_rev(struct commit *commit,
                                sprintf(new_name, "%.*s^%d", len, tip_name,
                                                parent_number);
 
-                       name_rev(parents->item, new_name,
-                               merge_traversals + 1 , 0, 0);
+                       name_rev(parents->item, new_name, 0,
+                               distance + MERGE_TRAVERSAL_WEIGHT, 0);
                } else {
-                       name_rev(parents->item, tip_name, merge_traversals,
-                               generation + 1, 0);
+                       name_rev(parents->item, tip_name, generation + 1,
+                               distance + 1, 0);
                }
        }
 }
@@ -126,18 +125,18 @@ static int name_ref(const char *path, const unsigned char *sha1, int flags, void
 }
 
 /* returns a static buffer */
-static const charget_rev_name(struct object *o)
+static const char *get_rev_name(struct object *o)
 {
        static char buffer[1024];
        struct rev_name *n;
        struct commit *c;
 
        if (o->type != OBJ_COMMIT)
-               return "undefined";
+               return NULL;
        c = (struct commit *) o;
        n = c->util;
        if (!n)
-               return "undefined";
+               return NULL;
 
        if (!n->generation)
                return n->tip_name;
@@ -152,51 +151,42 @@ static const char* get_rev_name(struct object *o)
        }
 }
 
+static char const * const name_rev_usage[] = {
+       "git-name-rev [options] ( --all | --stdin | <commit>... )",
+       NULL
+};
+
 int cmd_name_rev(int argc, const char **argv, const char *prefix)
 {
        struct object_array revs = { 0, 0, NULL };
-       int as_is = 0, all = 0, transform_stdin = 0;
+       int all = 0, transform_stdin = 0, allow_undefined = 1;
        struct name_ref_data data = { 0, 0, NULL };
+       struct option opts[] = {
+               OPT_BOOLEAN(0, "name-only", &data.name_only, "print only names (no SHA-1)"),
+               OPT_BOOLEAN(0, "tags", &data.tags_only, "only use tags to name the commits"),
+               OPT_STRING(0, "refs", &data.ref_filter, "pattern",
+                                  "only use refs matching <pattern>"),
+               OPT_GROUP(""),
+               OPT_BOOLEAN(0, "all", &all, "list all commits reachable from all refs"),
+               OPT_BOOLEAN(0, "stdin", &transform_stdin, "read from stdin"),
+               OPT_BOOLEAN(0, "undefined", &allow_undefined, "allow to print `undefined` names"),
+               OPT_END(),
+       };
 
        git_config(git_default_config);
+       argc = parse_options(argc, argv, opts, name_rev_usage, 0);
+       if (!!all + !!transform_stdin + !!argc > 1) {
+               error("Specify either a list, or --all, not both!");
+               usage_with_options(name_rev_usage, opts);
+       }
+       if (all || transform_stdin)
+               cutoff = 0;
 
-       if (argc < 2)
-               usage(name_rev_usage);
-
-       for (--argc, ++argv; argc; --argc, ++argv) {
+       for (; argc; argc--, argv++) {
                unsigned char sha1[20];
                struct object *o;
                struct commit *commit;
 
-               if (!as_is && (*argv)[0] == '-') {
-                       if (!strcmp(*argv, "--")) {
-                               as_is = 1;
-                               continue;
-                       } else if (!strcmp(*argv, "--name-only")) {
-                               data.name_only = 1;
-                               continue;
-                       } else if (!strcmp(*argv, "--tags")) {
-                               data.tags_only = 1;
-                               continue;
-                       } else  if (!prefixcmp(*argv, "--refs=")) {
-                               data.ref_filter = *argv + 7;
-                               continue;
-                       } else if (!strcmp(*argv, "--all")) {
-                               if (argc > 1)
-                                       die("Specify either a list, or --all, not both!");
-                               all = 1;
-                               cutoff = 0;
-                               continue;
-                       } else if (!strcmp(*argv, "--stdin")) {
-                               if (argc > 1)
-                                       die("Specify either a list, or --stdin, not both!");
-                               transform_stdin = 1;
-                               cutoff = 0;
-                               continue;
-                       }
-                       usage(name_rev_usage);
-               }
-
                if (get_sha1(*argv, sha1)) {
                        fprintf(stderr, "Could not get sha1 for %s. Skipping.\n",
                                        *argv);
@@ -211,10 +201,8 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
                }
 
                commit = (struct commit *)o;
-
                if (cutoff > commit->date)
                        cutoff = commit->date;
-
                add_object_array((struct object *)commit, *argv, &revs);
        }
 
@@ -239,7 +227,7 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
                                else if (++forty == 40 &&
                                                !ishex(*(p+1))) {
                                        unsigned char sha1[40];
-                                       const char *name = "undefined";
+                                       const char *name = NULL;
                                        char c = *(p+1);
 
                                        forty = 0;
@@ -253,11 +241,10 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
                                        }
                                        *(p+1) = c;
 
-                                       if (!strcmp(name, "undefined"))
+                                       if (!name)
                                                continue;
 
-                                       fwrite(p_start, p - p_start + 1, 1,
-                                              stdout);
+                                       fwrite(p_start, p - p_start + 1, 1, stdout);
                                        printf(" (%s)", name);
                                        p_start = p + 1;
                                }
@@ -273,18 +260,32 @@ int cmd_name_rev(int argc, const char **argv, const char *prefix)
                max = get_max_object_index();
                for (i = 0; i < max; i++) {
                        struct object * obj = get_indexed_object(i);
+                       const char *name;
                        if (!obj)
                                continue;
                        if (!data.name_only)
                                printf("%s ", sha1_to_hex(obj->sha1));
-                       printf("%s\n", get_rev_name(obj));
+                       name = get_rev_name(obj);
+                       if (name)
+                               printf("%s\n", name);
+                       else if (allow_undefined)
+                               printf("undefined\n");
+                       else
+                               die("cannot describe '%s'", sha1_to_hex(obj->sha1));
                }
        } else {
                int i;
                for (i = 0; i < revs.nr; i++) {
+                       const char *name;
                        if (!data.name_only)
                                printf("%s ", revs.objects[i].name);
-                       printf("%s\n", get_rev_name(revs.objects[i].item));
+                       name = get_rev_name(revs.objects[i].item);
+                       if (name)
+                               printf("%s\n", name);
+                       else if (allow_undefined)
+                               printf("undefined\n");
+                       else
+                               die("cannot describe '%s'", sha1_to_hex(revs.objects[i].item->sha1));
                }
        }