Andrew's git - gitweb.git/blob

   1/*
   2 * Builtin "git replace"
   3 *
   4 * Copyright (c) 2008 Christian Couder <chriscool@tuxfamily.org>
   5 *
   6 * Based on builtin/tag.c by Kristian Høgsberg <krh@redhat.com>
   7 * and Carlos Rica <jasampler@gmail.com> that was itself based on
   8 * git-tag.sh and mktag.c by Linus Torvalds.
   9 */
  10
  11#include "cache.h"
  12#include "builtin.h"
  13#include "refs.h"
  14#include "parse-options.h"
  15
  16static const char * const git_replace_usage[] = {
  17        N_("git replace [-f] <object> <replacement>"),
  18        N_("git replace -d <object>..."),
  19        N_("git replace [--format=<format>] [-l [<pattern>]]"),
  20        NULL
  21};
  22
  23enum repl_fmt { SHORT, MEDIUM, FULL };
  24
  25struct show_data {
  26        const char *pattern;
  27        enum repl_fmt fmt;
  28};
  29
  30static int show_reference(const char *refname, const unsigned char *sha1,
  31                          int flag, void *cb_data)
  32{
  33        struct show_data *data = cb_data;
  34
  35        if (!fnmatch(data->pattern, refname, 0)) {
  36                if (data->fmt == SHORT)
  37                        printf("%s\n", refname);
  38                else if (data->fmt == MEDIUM)
  39                        printf("%s -> %s\n", refname, sha1_to_hex(sha1));
  40                else { /* data->fmt == FULL */
  41                        unsigned char object[20];
  42                        enum object_type obj_type, repl_type;
  43
  44                        if (get_sha1(refname, object))
  45                                return error("Failed to resolve '%s' as a valid ref.", refname);
  46
  47                        obj_type = sha1_object_info(object, NULL);
  48                        repl_type = sha1_object_info(sha1, NULL);
  49
  50                        printf("%s (%s) -> %s (%s)\n", refname, typename(obj_type),
  51                               sha1_to_hex(sha1), typename(repl_type));
  52                }
  53        }
  54
  55        return 0;
  56}
  57
  58static int list_replace_refs(const char *pattern, const char *format)
  59{
  60        struct show_data data;
  61
  62        if (pattern == NULL)
  63                pattern = "*";
  64        data.pattern = pattern;
  65
  66        if (format == NULL || *format == '\0' || !strcmp(format, "short"))
  67                data.fmt = SHORT;
  68        else if (!strcmp(format, "medium"))
  69                data.fmt = MEDIUM;
  70        else if (!strcmp(format, "full"))
  71                data.fmt = FULL;
  72        else
  73                die("invalid replace format '%s'\n"
  74                    "valid formats are 'short', 'medium' and 'full'\n",
  75                    format);
  76
  77        for_each_replace_ref(show_reference, (void *) &data);
  78
  79        return 0;
  80}
  81
  82typedef int (*each_replace_name_fn)(const char *name, const char *ref,
  83                                    const unsigned char *sha1);
  84
  85static int for_each_replace_name(const char **argv, each_replace_name_fn fn)
  86{
  87        const char **p, *full_hex;
  88        char ref[PATH_MAX];
  89        int had_error = 0;
  90        unsigned char sha1[20];
  91
  92        for (p = argv; *p; p++) {
  93                if (get_sha1(*p, sha1)) {
  94                        error("Failed to resolve '%s' as a valid ref.", *p);
  95                        had_error = 1;
  96                        continue;
  97                }
  98                full_hex = sha1_to_hex(sha1);
  99                snprintf(ref, sizeof(ref), "refs/replace/%s", full_hex);
 100                /* read_ref() may reuse the buffer */
 101                full_hex = ref + strlen("refs/replace/");
 102                if (read_ref(ref, sha1)) {
 103                        error("replace ref '%s' not found.", full_hex);
 104                        had_error = 1;
 105                        continue;
 106                }
 107                if (fn(full_hex, ref, sha1))
 108                        had_error = 1;
 109        }
 110        return had_error;
 111}
 112
 113static int delete_replace_ref(const char *name, const char *ref,
 114                              const unsigned char *sha1)
 115{
 116        if (delete_ref(ref, sha1, 0))
 117                return 1;
 118        printf("Deleted replace ref '%s'\n", name);
 119        return 0;
 120}
 121
 122static int replace_object(const char *object_ref, const char *replace_ref,
 123                          int force)
 124{
 125        unsigned char object[20], prev[20], repl[20];
 126        enum object_type obj_type, repl_type;
 127        char ref[PATH_MAX];
 128        struct ref_lock *lock;
 129
 130        if (get_sha1(object_ref, object))
 131                die("Failed to resolve '%s' as a valid ref.", object_ref);
 132        if (get_sha1(replace_ref, repl))
 133                die("Failed to resolve '%s' as a valid ref.", replace_ref);
 134
 135        if (snprintf(ref, sizeof(ref),
 136                     "refs/replace/%s",
 137                     sha1_to_hex(object)) > sizeof(ref) - 1)
 138                die("replace ref name too long: %.*s...", 50, ref);
 139        if (check_refname_format(ref, 0))
 140                die("'%s' is not a valid ref name.", ref);
 141
 142        obj_type = sha1_object_info(object, NULL);
 143        repl_type = sha1_object_info(repl, NULL);
 144        if (!force && obj_type != repl_type)
 145                die("Objects must be of the same type.\n"
 146                    "'%s' points to a replaced object of type '%s'\n"
 147                    "while '%s' points to a replacement object of type '%s'.",
 148                    object_ref, typename(obj_type),
 149                    replace_ref, typename(repl_type));
 150
 151        if (read_ref(ref, prev))
 152                hashclr(prev);
 153        else if (!force)
 154                die("replace ref '%s' already exists", ref);
 155
 156        lock = lock_any_ref_for_update(ref, prev, 0, NULL);
 157        if (!lock)
 158                die("%s: cannot lock the ref", ref);
 159        if (write_ref_sha1(lock, repl, NULL) < 0)
 160                die("%s: cannot update the ref", ref);
 161
 162        return 0;
 163}
 164
 165int cmd_replace(int argc, const char **argv, const char *prefix)
 166{
 167        int list = 0, delete = 0, force = 0;
 168        const char *format = NULL;
 169        struct option options[] = {
 170                OPT_BOOL('l', "list", &list, N_("list replace refs")),
 171                OPT_BOOL('d', "delete", &delete, N_("delete replace refs")),
 172                OPT_BOOL('f', "force", &force, N_("replace the ref if it exists")),
 173                OPT_STRING(0, "format", &format, N_("format"), N_("use this format")),
 174                OPT_END()
 175        };
 176
 177        argc = parse_options(argc, argv, prefix, options, git_replace_usage, 0);
 178
 179        if (list && delete)
 180                usage_msg_opt("-l and -d cannot be used together",
 181                              git_replace_usage, options);
 182
 183        if (format && delete)
 184                usage_msg_opt("--format and -d cannot be used together",
 185                              git_replace_usage, options);
 186
 187        if (force && (list || delete))
 188                usage_msg_opt("-f cannot be used with -d or -l",
 189                              git_replace_usage, options);
 190
 191        /* Delete refs */
 192        if (delete) {
 193                if (argc < 1)
 194                        usage_msg_opt("-d needs at least one argument",
 195                                      git_replace_usage, options);
 196                return for_each_replace_name(argv, delete_replace_ref);
 197        }
 198
 199        /* Replace object */
 200        if (!list && argc) {
 201                if (argc != 2)
 202                        usage_msg_opt("bad number of arguments",
 203                                      git_replace_usage, options);
 204                if (format)
 205                        usage_msg_opt("--format cannot be used when not listing",
 206                                      git_replace_usage, options);
 207                return replace_object(argv[0], argv[1], force);
 208        }
 209
 210        /* List refs, even if "list" is not set */
 211        if (argc > 1)
 212                usage_msg_opt("only one pattern can be given with -l",
 213                              git_replace_usage, options);
 214        if (force)
 215                usage_msg_opt("-f needs some arguments",
 216                              git_replace_usage, options);
 217
 218        return list_replace_refs(argv[0], format);
 219}