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
  65static 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
  78static 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
  93static 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
 115static 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
 143static 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        update->have_old = 1;
 151
 152        if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 153                update_store_ref_name(update, ref.buf);
 154        else
 155                die("create line missing <ref>");
 156
 157        if ((next = parse_next_arg(next, &newvalue)) != NULL)
 158                update_store_new_sha1(update, newvalue.buf);
 159        else
 160                die("create %s missing <newvalue>", ref.buf);
 161        if (is_null_sha1(update->new_sha1))
 162                die("create %s given zero new value", ref.buf);
 163
 164        if (next && *next)
 165                die("create %s has extra input: %s", ref.buf, next);
 166}
 167
 168static void parse_cmd_delete(const char *next)
 169{
 170        struct strbuf ref = STRBUF_INIT;
 171        struct strbuf oldvalue = STRBUF_INIT;
 172        struct ref_update *update;
 173
 174        update = update_alloc();
 175
 176        if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 177                update_store_ref_name(update, ref.buf);
 178        else
 179                die("delete line missing <ref>");
 180
 181        if ((next = parse_next_arg(next, &oldvalue)) != NULL)
 182                update_store_old_sha1(update, oldvalue.buf);
 183        else if(!line_termination)
 184                die("delete %s missing [<oldvalue>] NUL", ref.buf);
 185        if (update->have_old && is_null_sha1(update->old_sha1))
 186                die("delete %s given zero old value", ref.buf);
 187
 188        if (next && *next)
 189                die("delete %s has extra input: %s", ref.buf, next);
 190}
 191
 192static void parse_cmd_verify(const char *next)
 193{
 194        struct strbuf ref = STRBUF_INIT;
 195        struct strbuf value = STRBUF_INIT;
 196        struct ref_update *update;
 197
 198        update = update_alloc();
 199
 200        if ((next = parse_first_arg(next, &ref)) != NULL && ref.buf[0])
 201                update_store_ref_name(update, ref.buf);
 202        else
 203                die("verify line missing <ref>");
 204
 205        if ((next = parse_next_arg(next, &value)) != NULL) {
 206                update_store_old_sha1(update, value.buf);
 207                update_store_new_sha1(update, value.buf);
 208        } else if(!line_termination)
 209                die("verify %s missing [<oldvalue>] NUL", ref.buf);
 210
 211        if (next && *next)
 212                die("verify %s has extra input: %s", ref.buf, next);
 213}
 214
 215static void parse_cmd_option(const char *next)
 216{
 217        if (!strcmp(next, "no-deref"))
 218                update_flags |= REF_NODEREF;
 219        else
 220                die("option unknown: %s", next);
 221}
 222
 223static void update_refs_stdin(void)
 224{
 225        struct strbuf cmd = STRBUF_INIT;
 226
 227        /* Read each line dispatch its command */
 228        while (strbuf_getline(&cmd, stdin, line_termination) != EOF)
 229                if (!cmd.buf[0])
 230                        die("empty command in input");
 231                else if (isspace(*cmd.buf))
 232                        die("whitespace before command: %s", cmd.buf);
 233                else if (starts_with(cmd.buf, "update "))
 234                        parse_cmd_update(cmd.buf + 7);
 235                else if (starts_with(cmd.buf, "create "))
 236                        parse_cmd_create(cmd.buf + 7);
 237                else if (starts_with(cmd.buf, "delete "))
 238                        parse_cmd_delete(cmd.buf + 7);
 239                else if (starts_with(cmd.buf, "verify "))
 240                        parse_cmd_verify(cmd.buf + 7);
 241                else if (starts_with(cmd.buf, "option "))
 242                        parse_cmd_option(cmd.buf + 7);
 243                else
 244                        die("unknown command: %s", cmd.buf);
 245
 246        strbuf_release(&cmd);
 247}
 248
 249int cmd_update_ref(int argc, const char **argv, const char *prefix)
 250{
 251        const char *refname, *oldval, *msg = NULL;
 252        unsigned char sha1[20], oldsha1[20];
 253        int delete = 0, no_deref = 0, read_stdin = 0, end_null = 0, flags = 0;
 254        struct option options[] = {
 255                OPT_STRING( 'm', NULL, &msg, N_("reason"), N_("reason of the update")),
 256                OPT_BOOL('d', NULL, &delete, N_("delete the reference")),
 257                OPT_BOOL( 0 , "no-deref", &no_deref,
 258                                        N_("update <refname> not the one it points to")),
 259                OPT_BOOL('z', NULL, &end_null, N_("stdin has NUL-terminated arguments")),
 260                OPT_BOOL( 0 , "stdin", &read_stdin, N_("read updates from stdin")),
 261                OPT_END(),
 262        };
 263
 264        git_config(git_default_config, NULL);
 265        argc = parse_options(argc, argv, prefix, options, git_update_ref_usage,
 266                             0);
 267        if (msg && !*msg)
 268                die("Refusing to perform update with empty message.");
 269
 270        if (read_stdin) {
 271                if (delete || no_deref || argc > 0)
 272                        usage_with_options(git_update_ref_usage, options);
 273                if (end_null)
 274                        line_termination = '\0';
 275                update_refs_stdin();
 276                return update_refs(msg, updates, updates_count, DIE_ON_ERR);
 277        }
 278
 279        if (end_null)
 280                usage_with_options(git_update_ref_usage, options);
 281
 282        if (delete) {
 283                if (argc < 1 || argc > 2)
 284                        usage_with_options(git_update_ref_usage, options);
 285                refname = argv[0];
 286                oldval = argv[1];
 287        } else {
 288                const char *value;
 289                if (argc < 2 || argc > 3)
 290                        usage_with_options(git_update_ref_usage, options);
 291                refname = argv[0];
 292                value = argv[1];
 293                oldval = argv[2];
 294                if (get_sha1(value, sha1))
 295                        die("%s: not a valid SHA1", value);
 296        }
 297
 298        hashclr(oldsha1); /* all-zero hash in case oldval is the empty string */
 299        if (oldval && *oldval && get_sha1(oldval, oldsha1))
 300                die("%s: not a valid old SHA1", oldval);
 301
 302        if (no_deref)
 303                flags = REF_NODEREF;
 304        if (delete)
 305                return delete_ref(refname, oldval ? oldsha1 : NULL, flags);
 306        else
 307                return update_ref(msg, refname, sha1, oldval ? oldsha1 : NULL,
 308                                  flags, DIE_ON_ERR);
 309}