From c8bae7493d2f2910b57f13ded012e86bdcfb0532 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sun, 7 Apr 2024 16:47:53 +0200 Subject: Adding upstream version 1:2.39.2. Signed-off-by: Daniel Baumann --- builtin/update-ref.c | 579 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 579 insertions(+) create mode 100644 builtin/update-ref.c (limited to 'builtin/update-ref.c') diff --git a/builtin/update-ref.c b/builtin/update-ref.c new file mode 100644 index 0000000..a84e7b4 --- /dev/null +++ b/builtin/update-ref.c @@ -0,0 +1,579 @@ +#include "cache.h" +#include "config.h" +#include "refs.h" +#include "builtin.h" +#include "parse-options.h" +#include "quote.h" +#include "strvec.h" + +static const char * const git_update_ref_usage[] = { + N_("git update-ref [] -d []"), + N_("git update-ref [] []"), + N_("git update-ref [] --stdin [-z]"), + NULL +}; + +static char line_termination = '\n'; +static unsigned int update_flags; +static unsigned int default_flags; +static unsigned create_reflog_flag; +static const char *msg; + +/* + * Parse one whitespace- or NUL-terminated, possibly C-quoted argument + * and append the result to arg. Return a pointer to the terminator. + * Die if there is an error in how the argument is C-quoted. This + * function is only used if not -z. + */ +static const char *parse_arg(const char *next, struct strbuf *arg) +{ + if (*next == '"') { + const char *orig = next; + + if (unquote_c_style(arg, next, &next)) + die("badly quoted argument: %s", orig); + if (*next && !isspace(*next)) + die("unexpected character after quoted argument: %s", orig); + } else { + while (*next && !isspace(*next)) + strbuf_addch(arg, *next++); + } + + return next; +} + +/* + * Parse the reference name immediately after "command SP". If not + * -z, then handle C-quoting. Return a pointer to a newly allocated + * string containing the name of the reference, or NULL if there was + * an error. Update *next to point at the character that terminates + * the argument. Die if C-quoting is malformed or the reference name + * is invalid. + */ +static char *parse_refname(const char **next) +{ + struct strbuf ref = STRBUF_INIT; + + if (line_termination) { + /* Without -z, use the next argument */ + *next = parse_arg(*next, &ref); + } else { + /* With -z, use everything up to the next NUL */ + strbuf_addstr(&ref, *next); + *next += ref.len; + } + + if (!ref.len) { + strbuf_release(&ref); + return NULL; + } + + if (check_refname_format(ref.buf, REFNAME_ALLOW_ONELEVEL)) + die("invalid ref format: %s", ref.buf); + + return strbuf_detach(&ref, NULL); +} + +/* + * The value being parsed is (as opposed to ; the + * difference affects which error messages are generated): + */ +#define PARSE_SHA1_OLD 0x01 + +/* + * For backwards compatibility, accept an empty string for update's + * in binary mode to be equivalent to specifying zeros. + */ +#define PARSE_SHA1_ALLOW_EMPTY 0x02 + +/* + * Parse an argument separator followed by the next argument, if any. + * If there is an argument, convert it to a SHA-1, write it to sha1, + * set *next to point at the character terminating the argument, and + * return 0. If there is no argument at all (not even the empty + * string), return 1 and leave *next unchanged. If the value is + * provided but cannot be converted to a SHA-1, die. flags can + * include PARSE_SHA1_OLD and/or PARSE_SHA1_ALLOW_EMPTY. + */ +static int parse_next_oid(const char **next, const char *end, + struct object_id *oid, + const char *command, const char *refname, + int flags) +{ + struct strbuf arg = STRBUF_INIT; + int ret = 0; + + if (*next == end) + goto eof; + + if (line_termination) { + /* Without -z, consume SP and use next argument */ + if (!**next || **next == line_termination) + return 1; + if (**next != ' ') + die("%s %s: expected SP but got: %s", + command, refname, *next); + (*next)++; + *next = parse_arg(*next, &arg); + if (arg.len) { + if (get_oid(arg.buf, oid)) + goto invalid; + } else { + /* Without -z, an empty value means all zeros: */ + oidclr(oid); + } + } else { + /* With -z, read the next NUL-terminated line */ + if (**next) + die("%s %s: expected NUL but got: %s", + command, refname, *next); + (*next)++; + if (*next == end) + goto eof; + strbuf_addstr(&arg, *next); + *next += arg.len; + + if (arg.len) { + if (get_oid(arg.buf, oid)) + goto invalid; + } else if (flags & PARSE_SHA1_ALLOW_EMPTY) { + /* With -z, treat an empty value as all zeros: */ + warning("%s %s: missing , treating as zero", + command, refname); + oidclr(oid); + } else { + /* + * With -z, an empty non-required value means + * unspecified: + */ + ret = 1; + } + } + + strbuf_release(&arg); + + return ret; + + invalid: + die(flags & PARSE_SHA1_OLD ? + "%s %s: invalid : %s" : + "%s %s: invalid : %s", + command, refname, arg.buf); + + eof: + die(flags & PARSE_SHA1_OLD ? + "%s %s: unexpected end of input when reading " : + "%s %s: unexpected end of input when reading ", + command, refname); +} + + +/* + * The following five parse_cmd_*() functions parse the corresponding + * command. In each case, next points at the character following the + * command name and the following space. They each return a pointer + * to the character terminating the command, and die with an + * explanatory message if there are any parsing problems. All of + * these functions handle either text or binary format input, + * depending on how line_termination is set. + */ + +static void parse_cmd_update(struct ref_transaction *transaction, + const char *next, const char *end) +{ + struct strbuf err = STRBUF_INIT; + char *refname; + struct object_id new_oid, old_oid; + int have_old; + + refname = parse_refname(&next); + if (!refname) + die("update: missing "); + + if (parse_next_oid(&next, end, &new_oid, "update", refname, + PARSE_SHA1_ALLOW_EMPTY)) + die("update %s: missing ", refname); + + have_old = !parse_next_oid(&next, end, &old_oid, "update", refname, + PARSE_SHA1_OLD); + + if (*next != line_termination) + die("update %s: extra input: %s", refname, next); + + if (ref_transaction_update(transaction, refname, + &new_oid, have_old ? &old_oid : NULL, + update_flags | create_reflog_flag, + msg, &err)) + die("%s", err.buf); + + update_flags = default_flags; + free(refname); + strbuf_release(&err); +} + +static void parse_cmd_create(struct ref_transaction *transaction, + const char *next, const char *end) +{ + struct strbuf err = STRBUF_INIT; + char *refname; + struct object_id new_oid; + + refname = parse_refname(&next); + if (!refname) + die("create: missing "); + + if (parse_next_oid(&next, end, &new_oid, "create", refname, 0)) + die("create %s: missing ", refname); + + if (is_null_oid(&new_oid)) + die("create %s: zero ", refname); + + if (*next != line_termination) + die("create %s: extra input: %s", refname, next); + + if (ref_transaction_create(transaction, refname, &new_oid, + update_flags | create_reflog_flag, + msg, &err)) + die("%s", err.buf); + + update_flags = default_flags; + free(refname); + strbuf_release(&err); +} + +static void parse_cmd_delete(struct ref_transaction *transaction, + const char *next, const char *end) +{ + struct strbuf err = STRBUF_INIT; + char *refname; + struct object_id old_oid; + int have_old; + + refname = parse_refname(&next); + if (!refname) + die("delete: missing "); + + if (parse_next_oid(&next, end, &old_oid, "delete", refname, + PARSE_SHA1_OLD)) { + have_old = 0; + } else { + if (is_null_oid(&old_oid)) + die("delete %s: zero ", refname); + have_old = 1; + } + + if (*next != line_termination) + die("delete %s: extra input: %s", refname, next); + + if (ref_transaction_delete(transaction, refname, + have_old ? &old_oid : NULL, + update_flags, msg, &err)) + die("%s", err.buf); + + update_flags = default_flags; + free(refname); + strbuf_release(&err); +} + +static void parse_cmd_verify(struct ref_transaction *transaction, + const char *next, const char *end) +{ + struct strbuf err = STRBUF_INIT; + char *refname; + struct object_id old_oid; + + refname = parse_refname(&next); + if (!refname) + die("verify: missing "); + + if (parse_next_oid(&next, end, &old_oid, "verify", refname, + PARSE_SHA1_OLD)) + oidclr(&old_oid); + + if (*next != line_termination) + die("verify %s: extra input: %s", refname, next); + + if (ref_transaction_verify(transaction, refname, &old_oid, + update_flags, &err)) + die("%s", err.buf); + + update_flags = default_flags; + free(refname); + strbuf_release(&err); +} + +static void report_ok(const char *command) +{ + fprintf(stdout, "%s: ok\n", command); + fflush(stdout); +} + +static void parse_cmd_option(struct ref_transaction *transaction, + const char *next, const char *end) +{ + const char *rest; + if (skip_prefix(next, "no-deref", &rest) && *rest == line_termination) + update_flags |= REF_NO_DEREF; + else + die("option unknown: %s", next); +} + +static void parse_cmd_start(struct ref_transaction *transaction, + const char *next, const char *end) +{ + if (*next != line_termination) + die("start: extra input: %s", next); + report_ok("start"); +} + +static void parse_cmd_prepare(struct ref_transaction *transaction, + const char *next, const char *end) +{ + struct strbuf error = STRBUF_INIT; + if (*next != line_termination) + die("prepare: extra input: %s", next); + if (ref_transaction_prepare(transaction, &error)) + die("prepare: %s", error.buf); + report_ok("prepare"); +} + +static void parse_cmd_abort(struct ref_transaction *transaction, + const char *next, const char *end) +{ + struct strbuf error = STRBUF_INIT; + if (*next != line_termination) + die("abort: extra input: %s", next); + if (ref_transaction_abort(transaction, &error)) + die("abort: %s", error.buf); + report_ok("abort"); +} + +static void parse_cmd_commit(struct ref_transaction *transaction, + const char *next, const char *end) +{ + struct strbuf error = STRBUF_INIT; + if (*next != line_termination) + die("commit: extra input: %s", next); + if (ref_transaction_commit(transaction, &error)) + die("commit: %s", error.buf); + report_ok("commit"); + ref_transaction_free(transaction); +} + +enum update_refs_state { + /* Non-transactional state open for updates. */ + UPDATE_REFS_OPEN, + /* A transaction has been started. */ + UPDATE_REFS_STARTED, + /* References are locked and ready for commit */ + UPDATE_REFS_PREPARED, + /* Transaction has been committed or closed. */ + UPDATE_REFS_CLOSED, +}; + +static const struct parse_cmd { + const char *prefix; + void (*fn)(struct ref_transaction *, const char *, const char *); + unsigned args; + enum update_refs_state state; +} command[] = { + { "update", parse_cmd_update, 3, UPDATE_REFS_OPEN }, + { "create", parse_cmd_create, 2, UPDATE_REFS_OPEN }, + { "delete", parse_cmd_delete, 2, UPDATE_REFS_OPEN }, + { "verify", parse_cmd_verify, 2, UPDATE_REFS_OPEN }, + { "option", parse_cmd_option, 1, UPDATE_REFS_OPEN }, + { "start", parse_cmd_start, 0, UPDATE_REFS_STARTED }, + { "prepare", parse_cmd_prepare, 0, UPDATE_REFS_PREPARED }, + { "abort", parse_cmd_abort, 0, UPDATE_REFS_CLOSED }, + { "commit", parse_cmd_commit, 0, UPDATE_REFS_CLOSED }, +}; + +static void update_refs_stdin(void) +{ + struct strbuf input = STRBUF_INIT, err = STRBUF_INIT; + enum update_refs_state state = UPDATE_REFS_OPEN; + struct ref_transaction *transaction; + int i, j; + + transaction = ref_transaction_begin(&err); + if (!transaction) + die("%s", err.buf); + + /* Read each line dispatch its command */ + while (!strbuf_getwholeline(&input, stdin, line_termination)) { + const struct parse_cmd *cmd = NULL; + + if (*input.buf == line_termination) + die("empty command in input"); + else if (isspace(*input.buf)) + die("whitespace before command: %s", input.buf); + + for (i = 0; i < ARRAY_SIZE(command); i++) { + const char *prefix = command[i].prefix; + char c; + + if (!starts_with(input.buf, prefix)) + continue; + + /* + * If the command has arguments, verify that it's + * followed by a space. Otherwise, it shall be followed + * by a line terminator. + */ + c = command[i].args ? ' ' : line_termination; + if (input.buf[strlen(prefix)] != c) + continue; + + cmd = &command[i]; + break; + } + if (!cmd) + die("unknown command: %s", input.buf); + + /* + * Read additional arguments if NUL-terminated. Do not raise an + * error in case there is an early EOF to let the command + * handle missing arguments with a proper error message. + */ + for (j = 1; line_termination == '\0' && j < cmd->args; j++) + if (strbuf_appendwholeline(&input, stdin, line_termination)) + break; + + switch (state) { + case UPDATE_REFS_OPEN: + case UPDATE_REFS_STARTED: + if (state == UPDATE_REFS_STARTED && cmd->state == UPDATE_REFS_STARTED) + die("cannot restart ongoing transaction"); + /* Do not downgrade a transaction to a non-transaction. */ + if (cmd->state >= state) + state = cmd->state; + break; + case UPDATE_REFS_PREPARED: + if (cmd->state != UPDATE_REFS_CLOSED) + die("prepared transactions can only be closed"); + state = cmd->state; + break; + case UPDATE_REFS_CLOSED: + if (cmd->state != UPDATE_REFS_STARTED) + die("transaction is closed"); + + /* + * Open a new transaction if we're currently closed and + * get a "start". + */ + state = cmd->state; + transaction = ref_transaction_begin(&err); + if (!transaction) + die("%s", err.buf); + + break; + } + + cmd->fn(transaction, input.buf + strlen(cmd->prefix) + !!cmd->args, + input.buf + input.len); + } + + switch (state) { + case UPDATE_REFS_OPEN: + /* Commit by default if no transaction was requested. */ + if (ref_transaction_commit(transaction, &err)) + die("%s", err.buf); + ref_transaction_free(transaction); + break; + case UPDATE_REFS_STARTED: + case UPDATE_REFS_PREPARED: + /* If using a transaction, we want to abort it. */ + if (ref_transaction_abort(transaction, &err)) + die("%s", err.buf); + break; + case UPDATE_REFS_CLOSED: + /* Otherwise no need to do anything, the transaction was closed already. */ + break; + } + + strbuf_release(&err); + strbuf_release(&input); +} + +int cmd_update_ref(int argc, const char **argv, const char *prefix) +{ + const char *refname, *oldval; + struct object_id oid, oldoid; + int delete = 0, no_deref = 0, read_stdin = 0, end_null = 0; + int create_reflog = 0; + struct option options[] = { + OPT_STRING( 'm', NULL, &msg, N_("reason"), N_("reason of the update")), + OPT_BOOL('d', NULL, &delete, N_("delete the reference")), + OPT_BOOL( 0 , "no-deref", &no_deref, + N_("update not the one it points to")), + OPT_BOOL('z', NULL, &end_null, N_("stdin has NUL-terminated arguments")), + OPT_BOOL( 0 , "stdin", &read_stdin, N_("read updates from stdin")), + OPT_BOOL( 0 , "create-reflog", &create_reflog, N_("create a reflog")), + OPT_END(), + }; + + git_config(git_default_config, NULL); + argc = parse_options(argc, argv, prefix, options, git_update_ref_usage, + 0); + if (msg && !*msg) + die("Refusing to perform update with empty message."); + + create_reflog_flag = create_reflog ? REF_FORCE_CREATE_REFLOG : 0; + + if (no_deref) { + default_flags = REF_NO_DEREF; + update_flags = default_flags; + } + + if (read_stdin) { + if (delete || argc > 0) + usage_with_options(git_update_ref_usage, options); + if (end_null) + line_termination = '\0'; + update_refs_stdin(); + return 0; + } + + if (end_null) + usage_with_options(git_update_ref_usage, options); + + if (delete) { + if (argc < 1 || argc > 2) + usage_with_options(git_update_ref_usage, options); + refname = argv[0]; + oldval = argv[1]; + } else { + const char *value; + if (argc < 2 || argc > 3) + usage_with_options(git_update_ref_usage, options); + refname = argv[0]; + value = argv[1]; + oldval = argv[2]; + if (get_oid(value, &oid)) + die("%s: not a valid SHA1", value); + } + + if (oldval) { + if (!*oldval) + /* + * The empty string implies that the reference + * must not already exist: + */ + oidclr(&oldoid); + else if (get_oid(oldval, &oldoid)) + die("%s: not a valid old SHA1", oldval); + } + + if (delete) + /* + * For purposes of backwards compatibility, we treat + * NULL_SHA1 as "don't care" here: + */ + return delete_ref(msg, refname, + (oldval && !is_null_oid(&oldoid)) ? &oldoid : NULL, + default_flags); + else + return update_ref(msg, refname, &oid, oldval ? &oldoid : NULL, + default_flags | create_reflog_flag, + UPDATE_REFS_DIE_ON_ERR); +} -- cgit v1.2.3