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 /*
  66  * Parse one whitespace- or NUL-terminated, possibly C-quoted argument
  67  * and append the result to arg.  Return a pointer to the terminator.
  68  * Die if there is an error in how the argument is C-quoted.  This
  69  * function is only used if not -z.
  70  */
  71 static const char *parse_arg(const char *next, struct strbuf *arg)
  72 {
  73         if (*next == '"') {
  74                 const char *orig = next;
  75
  76                 if (unquote_c_style(arg, next, &next))
  77                         die("badly quoted argument: %s", orig);
  78                 if (*next && !isspace(*next))
  79                         die("unexpected character after quoted argument: %s", orig);
  80         } else {
  81                 while (*next && !isspace(*next))
  82                         strbuf_addch(arg, *next++);
  83         }
  84
  85         return next;
  86 }
  87
  88 static const char *parse_first_arg(const char *next, struct strbuf *arg)
  89 {
  90         /* Parse argument immediately after "command SP" */
  91         strbuf_reset(arg);
  92         if (line_termination) {
  93                 /* Without -z, use the next argument */
  94                 next = parse_arg(next, arg);
  95         } else {
  96                 /* With -z, use rest of first NUL-terminated line */
  97                 strbuf_addstr(arg, next);
  98                 next = next + arg->len;
  99         }
 100         return next;
 101 }
 102
 103 static const char *parse_next_arg(const char *next, struct strbuf *arg)
 104 {
 105         /* Parse next SP-terminated or NUL-terminated argument, if any */
 106         strbuf_reset(arg);
 107         if (line_termination) {
 108                 /* Without -z, consume SP and use next argument */
 109                 if (!*next)
 110                         return NULL;
 111                 if (*next != ' ')
 112                         die("expected SP but got: %s", next);
 113                 next = parse_arg(next + 1, arg);
 114         } else {
 115                 /* With -z, read the next NUL-terminated line */
 116                 if (*next)
 117                         die("expected NUL but got: %s", next);
 118                 if (strbuf_getline(arg, stdin, '\0') == EOF)
 119                         return NULL;
 120                 next = arg->buf + arg->len;
 121         }
 122         return next;
 123 }
 124
 125 static void parse_cmd_update(const char *next)
 126 {
 127         struct strbuf ref = STRBUF_INIT;
 128         struct strbuf newvalue = STRBUF_INIT;
 129         struct strbuf oldvalue = STRBUF_INIT;
 130         struct ref_update *update;
 131
 132         update = update_alloc();
 133
 134         if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 135                 update_store_ref_name(update, ref.buf);
 136         else
 137                 die("update line missing <ref>");
 138
 139         if ((next = parse_next_arg(next, &newvalue)) != NULL)
 140                 update_store_new_sha1(update, newvalue.buf);
 141         else
 142                 die("update %s missing <newvalue>", ref.buf);
 143
 144         if ((next = parse_next_arg(next, &oldvalue)) != NULL)
 145                 update_store_old_sha1(update, oldvalue.buf);
 146         else if(!line_termination)
 147                 die("update %s missing [<oldvalue>] NUL", ref.buf);
 148
 149         if (next && *next)
 150                 die("update %s has extra input: %s", ref.buf, next);
 151 }
 152
 153 static void parse_cmd_create(const char *next)
 154 {
 155         struct strbuf ref = STRBUF_INIT;
 156         struct strbuf newvalue = STRBUF_INIT;
 157         struct ref_update *update;
 158
 159         update = update_alloc();
 160
 161         if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 162                 update_store_ref_name(update, ref.buf);
 163         else
 164                 die("create line missing <ref>");
 165
 166         if ((next = parse_next_arg(next, &newvalue)) != NULL)
 167                 update_store_new_sha1(update, newvalue.buf);
 168         else
 169                 die("create %s missing <newvalue>", ref.buf);
 170         if (is_null_sha1(update->new_sha1))
 171                 die("create %s given zero new value", ref.buf);
 172
 173         if (next && *next)
 174                 die("create %s has extra input: %s", ref.buf, next);
 175 }
 176
 177 static void parse_cmd_delete(const char *next)
 178 {
 179         struct strbuf ref = STRBUF_INIT;
 180         struct strbuf oldvalue = STRBUF_INIT;
 181         struct ref_update *update;
 182
 183         update = update_alloc();
 184
 185         if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 186                 update_store_ref_name(update, ref.buf);
 187         else
 188                 die("delete line missing <ref>");
 189
 190         if ((next = parse_next_arg(next, &oldvalue)) != NULL)
 191                 update_store_old_sha1(update, oldvalue.buf);
 192         else if(!line_termination)
 193                 die("delete %s missing [<oldvalue>] NUL", ref.buf);
 194         if (update->have_old && is_null_sha1(update->old_sha1))
 195                 die("delete %s given zero old value", ref.buf);
 196
 197         if (next && *next)
 198                 die("delete %s has extra input: %s", ref.buf, next);
 199 }
 200
 201 static void parse_cmd_verify(const char *next)
 202 {
 203         struct strbuf ref = STRBUF_INIT;
 204         struct strbuf value = STRBUF_INIT;
 205         struct ref_update *update;
 206
 207         update = update_alloc();
 208
 209         if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 210                 update_store_ref_name(update, ref.buf);
 211         else
 212                 die("verify line missing <ref>");
 213
 214         if ((next = parse_next_arg(next, &value)) != NULL) {
 215                 update_store_old_sha1(update, value.buf);
 216                 update_store_new_sha1(update, value.buf);
 217         } else if(!line_termination)
 218                 die("verify %s missing [<oldvalue>] NUL", ref.buf);
 219
 220         if (next && *next)
 221                 die("verify %s has extra input: %s", ref.buf, next);
 222 }
 223
 224 static void parse_cmd_option(const char *next)
 225 {
 226         if (!strcmp(next, "no-deref"))
 227                 update_flags |= REF_NODEREF;
 228         else
 229                 die("option unknown: %s", next);
 230 }
 231
 232 static void update_refs_stdin(void)
 233 {
 234         struct strbuf cmd = STRBUF_INIT;
 235
 236         /* Read each line dispatch its command */
 237         while (strbuf_getline(&cmd, stdin, line_termination) != EOF)
 238                 if (!cmd.buf[0])
 239                         die("empty command in input");
 240                 else if (isspace(*cmd.buf))
 241                         die("whitespace before command: %s", cmd.buf);
 242                 else if (starts_with(cmd.buf, "update "))
 243                         parse_cmd_update(cmd.buf + 7);
 244                 else if (starts_with(cmd.buf, "create "))
 245                         parse_cmd_create(cmd.buf + 7);
 246                 else if (starts_with(cmd.buf, "delete "))
 247                         parse_cmd_delete(cmd.buf + 7);
 248                 else if (starts_with(cmd.buf, "verify "))
 249                         parse_cmd_verify(cmd.buf + 7);
 250                 else if (starts_with(cmd.buf, "option "))
 251                         parse_cmd_option(cmd.buf + 7);
 252                 else
 253                         die("unknown command: %s", cmd.buf);
 254
 255         strbuf_release(&cmd);
 256 }
 257
 258 int cmd_update_ref(int argc, const char **argv, const char *prefix)
 259 {
 260         const char *refname, *oldval, *msg = NULL;
 261         unsigned char sha1[20], oldsha1[20];
 262         int delete = 0, no_deref = 0, read_stdin = 0, end_null = 0, flags = 0;
 263         struct option options[] = {
 264                 OPT_STRING( 'm', NULL, &msg, N_("reason"), N_("reason of the update")),
 265                 OPT_BOOL('d', NULL, &delete, N_("delete the reference")),
 266                 OPT_BOOL( 0 , "no-deref", &no_deref,
 267                                         N_("update <refname> not the one it points to")),
 268                 OPT_BOOL('z', NULL, &end_null, N_("stdin has NUL-terminated arguments")),
 269                 OPT_BOOL( 0 , "stdin", &read_stdin, N_("read updates from stdin")),
 270                 OPT_END(),
 271         };
 272
 273         git_config(git_default_config, NULL);
 274         argc = parse_options(argc, argv, prefix, options, git_update_ref_usage,
 275                              0);
 276         if (msg && !*msg)
 277                 die("Refusing to perform update with empty message.");
 278
 279         if (read_stdin) {
 280                 if (delete || no_deref || argc > 0)
 281                         usage_with_options(git_update_ref_usage, options);
 282                 if (end_null)
 283                         line_termination = '\0';
 284                 update_refs_stdin();
 285                 return update_refs(msg, updates, updates_count, DIE_ON_ERR);
 286         }
 287
 288         if (end_null)
 289                 usage_with_options(git_update_ref_usage, options);
 290
 291         if (delete) {
 292                 if (argc < 1 || argc > 2)
 293                         usage_with_options(git_update_ref_usage, options);
 294                 refname = argv[0];
 295                 oldval = argv[1];
 296         } else {
 297                 const char *value;
 298                 if (argc < 2 || argc > 3)
 299                         usage_with_options(git_update_ref_usage, options);
 300                 refname = argv[0];
 301                 value = argv[1];
 302                 oldval = argv[2];
 303                 if (get_sha1(value, sha1))
 304                         die("%s: not a valid SHA1", value);
 305         }
 306
 307         hashclr(oldsha1); /* all-zero hash in case oldval is the empty string */
 308         if (oldval && *oldval && get_sha1(oldval, oldsha1))
 309                 die("%s: not a valid old SHA1", oldval);
 310
 311         if (no_deref)
 312                 flags = REF_NODEREF;
 313         if (delete)
 314                 return delete_ref(refname, oldval ? oldsha1 : NULL, flags);
 315         else
 316                 return update_ref(msg, refname, sha1, oldval ? oldsha1 : NULL,
 317                                   flags, DIE_ON_ERR);
 318 }