Andrew's git - gitweb.git/blob - 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
   8static 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
  15static int updates_alloc;
  16static int updates_count;
  17static const struct ref_update **updates;
  18
  19static char line_termination = '\n';
  20static int update_flags;
  21
  22static 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
  38static 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
  46static 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
  54static 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 */
  71static 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
  88static 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
 103static 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
 125static 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
 153static 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
 177static 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
 201static 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
 224static 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
 232static 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
 258int 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}