builtin/update-ref.c

   1 #include "cache.h"
   2 #include "refs.h"
   3 #include "builtin.h"
   4 #include "parse-options.h"
   5 #include "quote.h"
   6 #include "argv-array.h"
   7
   8 static const char * const git_update_ref_usage[] = {
   9         N_("git update-ref [options] -d <refname> [<oldval>]"),
  10         N_("git update-ref [options]    <refname> <newval> [<oldval>]"),
  11         N_("git update-ref [options] --stdin [-z]"),
  12         NULL
  13 };
  14
  15 static int updates_alloc;
  16 static int updates_count;
  17 static const struct ref_update **updates;
  18
  19 static char line_termination = '\n';
  20 static int update_flags;
  21
  22 static struct ref_update *update_alloc(void)
  23 {
  24         struct ref_update *update;
  25
  26         /* Allocate and zero-init a struct ref_update */
  27         update = xcalloc(1, sizeof(*update));
  28         ALLOC_GROW(updates, updates_count + 1, updates_alloc);
  29         updates[updates_count++] = update;
  30
  31         /* Store and reset accumulated options */
  32         update->flags = update_flags;
  33         update_flags = 0;
  34
  35         return update;
  36 }
  37
  38 static void update_store_ref_name(struct ref_update *update,
  39                                   const char *ref_name)
  40 {
  41         if (check_refname_format(ref_name, REFNAME_ALLOW_ONELEVEL))
  42                 die("invalid ref format: %s", ref_name);
  43         update->ref_name = xstrdup(ref_name);
  44 }
  45
  46 static void update_store_new_sha1(struct ref_update *update,
  47                                   const char *newvalue)
  48 {
  49         if (*newvalue && get_sha1(newvalue, update->new_sha1))
  50                 die("invalid new value for ref %s: %s",
  51                     update->ref_name, newvalue);
  52 }
  53
  54 static void update_store_old_sha1(struct ref_update *update,
  55                                   const char *oldvalue)
  56 {
  57         if (*oldvalue && get_sha1(oldvalue, update->old_sha1))
  58                 die("invalid old value for ref %s: %s",
  59                     update->ref_name, oldvalue);
  60
  61         /* We have an old value if non-empty, or if empty without -z */
  62         update->have_old = *oldvalue || line_termination;
  63 }
  64
  65 static const char *parse_arg(const char *next, struct strbuf *arg)
  66 {
  67         /* Parse SP-terminated, possibly C-quoted argument */
  68         if (*next != '"')
  69                 while (*next && !isspace(*next))
  70                         strbuf_addch(arg, *next++);
  71         else if (unquote_c_style(arg, next, &next))
  72                 die("badly quoted argument: %s", next);
  73
  74         /* Return position after the argument */
  75         return next;
  76 }
  77
  78 static const char *parse_first_arg(const char *next, struct strbuf *arg)
  79 {
  80         /* Parse argument immediately after "command SP" */
  81         strbuf_reset(arg);
  82         if (line_termination) {
  83                 /* Without -z, use the next argument */
  84                 next = parse_arg(next, arg);
  85         } else {
  86                 /* With -z, use rest of first NUL-terminated line */
  87                 strbuf_addstr(arg, next);
  88                 next = next + arg->len;
  89         }
  90         return next;
  91 }
  92
  93 static const char *parse_next_arg(const char *next, struct strbuf *arg)
  94 {
  95         /* Parse next SP-terminated or NUL-terminated argument, if any */
  96         strbuf_reset(arg);
  97         if (line_termination) {
  98                 /* Without -z, consume SP and use next argument */
  99                 if (!*next)
 100                         return NULL;
 101                 if (*next != ' ')
 102                         die("expected SP but got: %s", next);
 103                 next = parse_arg(next + 1, arg);
 104         } else {
 105                 /* With -z, read the next NUL-terminated line */
 106                 if (*next)
 107                         die("expected NUL but got: %s", next);
 108                 if (strbuf_getline(arg, stdin, '\0') == EOF)
 109                         return NULL;
 110                 next = arg->buf + arg->len;
 111         }
 112         return next;
 113 }
 114
 115 static void parse_cmd_update(const char *next)
 116 {
 117         struct strbuf ref = STRBUF_INIT;
 118         struct strbuf newvalue = STRBUF_INIT;
 119         struct strbuf oldvalue = STRBUF_INIT;
 120         struct ref_update *update;
 121
 122         update = update_alloc();
 123
 124         if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 125                 update_store_ref_name(update, ref.buf);
 126         else
 127                 die("update line missing <ref>");
 128
 129         if ((next = parse_next_arg(next, &newvalue)) != NULL)
 130                 update_store_new_sha1(update, newvalue.buf);
 131         else
 132                 die("update %s missing <newvalue>", ref.buf);
 133
 134         if ((next = parse_next_arg(next, &oldvalue)) != NULL)
 135                 update_store_old_sha1(update, oldvalue.buf);
 136         else if(!line_termination)
 137                 die("update %s missing [<oldvalue>] NUL", ref.buf);
 138
 139         if (next && *next)
 140                 die("update %s has extra input: %s", ref.buf, next);
 141 }
 142
 143 static void parse_cmd_create(const char *next)
 144 {
 145         struct strbuf ref = STRBUF_INIT;
 146         struct strbuf newvalue = STRBUF_INIT;
 147         struct ref_update *update;
 148
 149         update = update_alloc();
 150
 151         if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 152                 update_store_ref_name(update, ref.buf);
 153         else
 154                 die("create line missing <ref>");
 155
 156         if ((next = parse_next_arg(next, &newvalue)) != NULL)
 157                 update_store_new_sha1(update, newvalue.buf);
 158         else
 159                 die("create %s missing <newvalue>", ref.buf);
 160         if (is_null_sha1(update->new_sha1))
 161                 die("create %s given zero new value", ref.buf);
 162
 163         if (next && *next)
 164                 die("create %s has extra input: %s", ref.buf, next);
 165 }
 166
 167 static void parse_cmd_delete(const char *next)
 168 {
 169         struct strbuf ref = STRBUF_INIT;
 170         struct strbuf oldvalue = STRBUF_INIT;
 171         struct ref_update *update;
 172
 173         update = update_alloc();
 174
 175         if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 176                 update_store_ref_name(update, ref.buf);
 177         else
 178                 die("delete line missing <ref>");
 179
 180         if ((next = parse_next_arg(next, &oldvalue)) != NULL)
 181                 update_store_old_sha1(update, oldvalue.buf);
 182         else if(!line_termination)
 183                 die("delete %s missing [<oldvalue>] NUL", ref.buf);
 184         if (update->have_old && is_null_sha1(update->old_sha1))
 185                 die("delete %s given zero old value", ref.buf);
 186
 187         if (next && *next)
 188                 die("delete %s has extra input: %s", ref.buf, next);
 189 }
 190
 191 static void parse_cmd_verify(const char *next)
 192 {
 193         struct strbuf ref = STRBUF_INIT;
 194         struct strbuf value = STRBUF_INIT;
 195         struct ref_update *update;
 196
 197         update = update_alloc();
 198
 199         if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 200                 update_store_ref_name(update, ref.buf);
 201         else
 202                 die("verify line missing <ref>");
 203
 204         if ((next = parse_next_arg(next, &value)) != NULL) {
 205                 update_store_old_sha1(update, value.buf);
 206                 update_store_new_sha1(update, value.buf);
 207         } else if(!line_termination)
 208                 die("verify %s missing [<oldvalue>] NUL", ref.buf);
 209
 210         if (next && *next)
 211                 die("verify %s has extra input: %s", ref.buf, next);
 212 }
 213
 214 static void parse_cmd_option(const char *next)
 215 {
 216         if (!strcmp(next, "no-deref"))
 217                 update_flags |= REF_NODEREF;
 218         else
 219                 die("option unknown: %s", next);
 220 }
 221
 222 static void update_refs_stdin(void)
 223 {
 224         struct strbuf cmd = STRBUF_INIT;
 225
 226         /* Read each line dispatch its command */
 227         while (strbuf_getline(&cmd, stdin, line_termination) != EOF)
 228                 if (!cmd.buf[0])
 229                         die("empty command in input");
 230                 else if (isspace(*cmd.buf))
 231                         die("whitespace before command: %s", cmd.buf);
 232                 else if (!prefixcmp(cmd.buf, "update "))
 233                         parse_cmd_update(cmd.buf + 7);
 234                 else if (!prefixcmp(cmd.buf, "create "))
 235                         parse_cmd_create(cmd.buf + 7);
 236                 else if (!prefixcmp(cmd.buf, "delete "))
 237                         parse_cmd_delete(cmd.buf + 7);
 238                 else if (!prefixcmp(cmd.buf, "verify "))
 239                         parse_cmd_verify(cmd.buf + 7);
 240                 else if (!prefixcmp(cmd.buf, "option "))
 241                         parse_cmd_option(cmd.buf + 7);
 242                 else
 243                         die("unknown command: %s", cmd.buf);
 244
 245         strbuf_release(&cmd);
 246 }
 247
 248 int cmd_update_ref(int argc, const char **argv, const char *prefix)
 249 {
 250         const char *refname, *oldval, *msg = NULL;
 251         unsigned char sha1[20], oldsha1[20];
 252         int delete = 0, no_deref = 0, read_stdin = 0, end_null = 0, flags = 0;
 253         struct option options[] = {
 254                 OPT_STRING( 'm', NULL, &msg, N_("reason"), N_("reason of the update")),
 255                 OPT_BOOL('d', NULL, &delete, N_("delete the reference")),
 256                 OPT_BOOL( 0 , "no-deref", &no_deref,
 257                                         N_("update <refname> not the one it points to")),
 258                 OPT_BOOL('z', NULL, &end_null, N_("stdin has NUL-terminated arguments")),
 259                 OPT_BOOL( 0 , "stdin", &read_stdin, N_("read updates from stdin")),
 260                 OPT_END(),
 261         };
 262
 263         git_config(git_default_config, NULL);
 264         argc = parse_options(argc, argv, prefix, options, git_update_ref_usage,
 265                              0);
 266         if (msg && !*msg)
 267                 die("Refusing to perform update with empty message.");
 268
 269         if (read_stdin) {
 270                 if (delete || no_deref || argc > 0)
 271                         usage_with_options(git_update_ref_usage, options);
 272                 if (end_null)
 273                         line_termination = '\0';
 274                 update_refs_stdin();
 275                 return update_refs(msg, updates, updates_count, DIE_ON_ERR);
 276         }
 277
 278         if (end_null)
 279                 usage_with_options(git_update_ref_usage, options);
 280
 281         if (delete) {
 282                 if (argc < 1 || argc > 2)
 283                         usage_with_options(git_update_ref_usage, options);
 284                 refname = argv[0];
 285                 oldval = argv[1];
 286         } else {
 287                 const char *value;
 288                 if (argc < 2 || argc > 3)
 289                         usage_with_options(git_update_ref_usage, options);
 290                 refname = argv[0];
 291                 value = argv[1];
 292                 oldval = argv[2];
 293                 if (get_sha1(value, sha1))
 294                         die("%s: not a valid SHA1", value);
 295         }
 296
 297         hashclr(oldsha1); /* all-zero hash in case oldval is the empty string */
 298         if (oldval && *oldval && get_sha1(oldval, oldsha1))
 299                 die("%s: not a valid old SHA1", oldval);
 300
 301         if (no_deref)
 302                 flags = REF_NODEREF;
 303         if (delete)
 304                 return delete_ref(refname, oldval ? oldsha1 : NULL, flags);
 305         else
 306                 return update_ref(msg, refname, sha1, oldval ? oldsha1 : NULL,
 307                                   flags, DIE_ON_ERR);
 308 }