mv: flatten error handling code block
[git/mingw.git] / builtin / update-ref.c
blob3067b11310fb01e9e05a1988898566f211601e07
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"
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
15 static struct ref_transaction *transaction;
17 static char line_termination = '\n';
18 static int update_flags;
19 static struct strbuf err = STRBUF_INIT;
22 * Parse one whitespace- or NUL-terminated, possibly C-quoted argument
23 * and append the result to arg. Return a pointer to the terminator.
24 * Die if there is an error in how the argument is C-quoted. This
25 * function is only used if not -z.
27 static const char *parse_arg(const char *next, struct strbuf *arg)
29 if (*next == '"') {
30 const char *orig = next;
32 if (unquote_c_style(arg, next, &next))
33 die("badly quoted argument: %s", orig);
34 if (*next && !isspace(*next))
35 die("unexpected character after quoted argument: %s", orig);
36 } else {
37 while (*next && !isspace(*next))
38 strbuf_addch(arg, *next++);
41 return next;
45 * Parse the reference name immediately after "command SP". If not
46 * -z, then handle C-quoting. Return a pointer to a newly allocated
47 * string containing the name of the reference, or NULL if there was
48 * an error. Update *next to point at the character that terminates
49 * the argument. Die if C-quoting is malformed or the reference name
50 * is invalid.
52 static char *parse_refname(struct strbuf *input, const char **next)
54 struct strbuf ref = STRBUF_INIT;
56 if (line_termination) {
57 /* Without -z, use the next argument */
58 *next = parse_arg(*next, &ref);
59 } else {
60 /* With -z, use everything up to the next NUL */
61 strbuf_addstr(&ref, *next);
62 *next += ref.len;
65 if (!ref.len) {
66 strbuf_release(&ref);
67 return NULL;
70 if (check_refname_format(ref.buf, REFNAME_ALLOW_ONELEVEL))
71 die("invalid ref format: %s", ref.buf);
73 return strbuf_detach(&ref, NULL);
77 * The value being parsed is <oldvalue> (as opposed to <newvalue>; the
78 * difference affects which error messages are generated):
80 #define PARSE_SHA1_OLD 0x01
83 * For backwards compatibility, accept an empty string for update's
84 * <newvalue> in binary mode to be equivalent to specifying zeros.
86 #define PARSE_SHA1_ALLOW_EMPTY 0x02
89 * Parse an argument separator followed by the next argument, if any.
90 * If there is an argument, convert it to a SHA-1, write it to sha1,
91 * set *next to point at the character terminating the argument, and
92 * return 0. If there is no argument at all (not even the empty
93 * string), return 1 and leave *next unchanged. If the value is
94 * provided but cannot be converted to a SHA-1, die. flags can
95 * include PARSE_SHA1_OLD and/or PARSE_SHA1_ALLOW_EMPTY.
97 static int parse_next_sha1(struct strbuf *input, const char **next,
98 unsigned char *sha1,
99 const char *command, const char *refname,
100 int flags)
102 struct strbuf arg = STRBUF_INIT;
103 int ret = 0;
105 if (*next == input->buf + input->len)
106 goto eof;
108 if (line_termination) {
109 /* Without -z, consume SP and use next argument */
110 if (!**next || **next == line_termination)
111 return 1;
112 if (**next != ' ')
113 die("%s %s: expected SP but got: %s",
114 command, refname, *next);
115 (*next)++;
116 *next = parse_arg(*next, &arg);
117 if (arg.len) {
118 if (get_sha1(arg.buf, sha1))
119 goto invalid;
120 } else {
121 /* Without -z, an empty value means all zeros: */
122 hashclr(sha1);
124 } else {
125 /* With -z, read the next NUL-terminated line */
126 if (**next)
127 die("%s %s: expected NUL but got: %s",
128 command, refname, *next);
129 (*next)++;
130 if (*next == input->buf + input->len)
131 goto eof;
132 strbuf_addstr(&arg, *next);
133 *next += arg.len;
135 if (arg.len) {
136 if (get_sha1(arg.buf, sha1))
137 goto invalid;
138 } else if (flags & PARSE_SHA1_ALLOW_EMPTY) {
139 /* With -z, treat an empty value as all zeros: */
140 warning("%s %s: missing <newvalue>, treating as zero",
141 command, refname);
142 hashclr(sha1);
143 } else {
145 * With -z, an empty non-required value means
146 * unspecified:
148 ret = 1;
152 strbuf_release(&arg);
154 return ret;
156 invalid:
157 die(flags & PARSE_SHA1_OLD ?
158 "%s %s: invalid <oldvalue>: %s" :
159 "%s %s: invalid <newvalue>: %s",
160 command, refname, arg.buf);
162 eof:
163 die(flags & PARSE_SHA1_OLD ?
164 "%s %s: unexpected end of input when reading <oldvalue>" :
165 "%s %s: unexpected end of input when reading <newvalue>",
166 command, refname);
171 * The following five parse_cmd_*() functions parse the corresponding
172 * command. In each case, next points at the character following the
173 * command name and the following space. They each return a pointer
174 * to the character terminating the command, and die with an
175 * explanatory message if there are any parsing problems. All of
176 * these functions handle either text or binary format input,
177 * depending on how line_termination is set.
180 static const char *parse_cmd_update(struct strbuf *input, const char *next)
182 char *refname;
183 unsigned char new_sha1[20];
184 unsigned char old_sha1[20];
185 int have_old;
187 refname = parse_refname(input, &next);
188 if (!refname)
189 die("update: missing <ref>");
191 if (parse_next_sha1(input, &next, new_sha1, "update", refname,
192 PARSE_SHA1_ALLOW_EMPTY))
193 die("update %s: missing <newvalue>", refname);
195 have_old = !parse_next_sha1(input, &next, old_sha1, "update", refname,
196 PARSE_SHA1_OLD);
198 if (*next != line_termination)
199 die("update %s: extra input: %s", refname, next);
201 if (ref_transaction_update(transaction, refname, new_sha1, old_sha1,
202 update_flags, have_old, &err))
203 die("%s", err.buf);
205 update_flags = 0;
206 free(refname);
208 return next;
211 static const char *parse_cmd_create(struct strbuf *input, const char *next)
213 char *refname;
214 unsigned char new_sha1[20];
216 refname = parse_refname(input, &next);
217 if (!refname)
218 die("create: missing <ref>");
220 if (parse_next_sha1(input, &next, new_sha1, "create", refname, 0))
221 die("create %s: missing <newvalue>", refname);
223 if (is_null_sha1(new_sha1))
224 die("create %s: zero <newvalue>", refname);
226 if (*next != line_termination)
227 die("create %s: extra input: %s", refname, next);
229 ref_transaction_create(transaction, refname, new_sha1, update_flags);
231 update_flags = 0;
232 free(refname);
234 return next;
237 static const char *parse_cmd_delete(struct strbuf *input, const char *next)
239 char *refname;
240 unsigned char old_sha1[20];
241 int have_old;
243 refname = parse_refname(input, &next);
244 if (!refname)
245 die("delete: missing <ref>");
247 if (parse_next_sha1(input, &next, old_sha1, "delete", refname,
248 PARSE_SHA1_OLD)) {
249 have_old = 0;
250 } else {
251 if (is_null_sha1(old_sha1))
252 die("delete %s: zero <oldvalue>", refname);
253 have_old = 1;
256 if (*next != line_termination)
257 die("delete %s: extra input: %s", refname, next);
259 ref_transaction_delete(transaction, refname, old_sha1,
260 update_flags, have_old);
262 update_flags = 0;
263 free(refname);
265 return next;
268 static const char *parse_cmd_verify(struct strbuf *input, const char *next)
270 char *refname;
271 unsigned char new_sha1[20];
272 unsigned char old_sha1[20];
273 int have_old;
275 refname = parse_refname(input, &next);
276 if (!refname)
277 die("verify: missing <ref>");
279 if (parse_next_sha1(input, &next, old_sha1, "verify", refname,
280 PARSE_SHA1_OLD)) {
281 hashclr(new_sha1);
282 have_old = 0;
283 } else {
284 hashcpy(new_sha1, old_sha1);
285 have_old = 1;
288 if (*next != line_termination)
289 die("verify %s: extra input: %s", refname, next);
291 if (ref_transaction_update(transaction, refname, new_sha1, old_sha1,
292 update_flags, have_old, &err))
293 die("%s", err.buf);
295 update_flags = 0;
296 free(refname);
298 return next;
301 static const char *parse_cmd_option(struct strbuf *input, const char *next)
303 if (!strncmp(next, "no-deref", 8) && next[8] == line_termination)
304 update_flags |= REF_NODEREF;
305 else
306 die("option unknown: %s", next);
307 return next + 8;
310 static void update_refs_stdin(void)
312 struct strbuf input = STRBUF_INIT;
313 const char *next;
315 if (strbuf_read(&input, 0, 1000) < 0)
316 die_errno("could not read from stdin");
317 next = input.buf;
318 /* Read each line dispatch its command */
319 while (next < input.buf + input.len) {
320 if (*next == line_termination)
321 die("empty command in input");
322 else if (isspace(*next))
323 die("whitespace before command: %s", next);
324 else if (starts_with(next, "update "))
325 next = parse_cmd_update(&input, next + 7);
326 else if (starts_with(next, "create "))
327 next = parse_cmd_create(&input, next + 7);
328 else if (starts_with(next, "delete "))
329 next = parse_cmd_delete(&input, next + 7);
330 else if (starts_with(next, "verify "))
331 next = parse_cmd_verify(&input, next + 7);
332 else if (starts_with(next, "option "))
333 next = parse_cmd_option(&input, next + 7);
334 else
335 die("unknown command: %s", next);
337 next++;
340 strbuf_release(&input);
343 int cmd_update_ref(int argc, const char **argv, const char *prefix)
345 const char *refname, *oldval, *msg = NULL;
346 unsigned char sha1[20], oldsha1[20];
347 int delete = 0, no_deref = 0, read_stdin = 0, end_null = 0, flags = 0;
348 struct option options[] = {
349 OPT_STRING( 'm', NULL, &msg, N_("reason"), N_("reason of the update")),
350 OPT_BOOL('d', NULL, &delete, N_("delete the reference")),
351 OPT_BOOL( 0 , "no-deref", &no_deref,
352 N_("update <refname> not the one it points to")),
353 OPT_BOOL('z', NULL, &end_null, N_("stdin has NUL-terminated arguments")),
354 OPT_BOOL( 0 , "stdin", &read_stdin, N_("read updates from stdin")),
355 OPT_END(),
358 git_config(git_default_config, NULL);
359 argc = parse_options(argc, argv, prefix, options, git_update_ref_usage,
361 if (msg && !*msg)
362 die("Refusing to perform update with empty message.");
364 if (read_stdin) {
365 transaction = ref_transaction_begin();
366 if (delete || no_deref || argc > 0)
367 usage_with_options(git_update_ref_usage, options);
368 if (end_null)
369 line_termination = '\0';
370 update_refs_stdin();
371 if (ref_transaction_commit(transaction, msg, &err))
372 die("%s", err.buf);
373 ref_transaction_free(transaction);
374 return 0;
377 if (end_null)
378 usage_with_options(git_update_ref_usage, options);
380 if (delete) {
381 if (argc < 1 || argc > 2)
382 usage_with_options(git_update_ref_usage, options);
383 refname = argv[0];
384 oldval = argv[1];
385 } else {
386 const char *value;
387 if (argc < 2 || argc > 3)
388 usage_with_options(git_update_ref_usage, options);
389 refname = argv[0];
390 value = argv[1];
391 oldval = argv[2];
392 if (get_sha1(value, sha1))
393 die("%s: not a valid SHA1", value);
396 hashclr(oldsha1); /* all-zero hash in case oldval is the empty string */
397 if (oldval && *oldval && get_sha1(oldval, oldsha1))
398 die("%s: not a valid old SHA1", oldval);
400 if (no_deref)
401 flags = REF_NODEREF;
402 if (delete)
403 return delete_ref(refname, oldval ? oldsha1 : NULL, flags);
404 else
405 return update_ref(msg, refname, sha1, oldval ? oldsha1 : NULL,
406 flags, UPDATE_REFS_DIE_ON_ERR);