From 5c387428f10c27c24d3adb890cd466e2300518fa Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Nguy=E1=BB=85n=20Th=C3=A1i=20Ng=E1=BB=8Dc=20Duy?= Date: Mon, 29 Apr 2019 17:05:25 +0700 Subject: parse-options: don't emit "ambiguous option" for aliases MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Change the option parsing machinery so that e.g. "clone --recurs ..." doesn't error out because "clone" understands both "--recursive" and "--recurse-submodules" to mean the same thing. Initially "clone" just understood --recursive until the --recurses-submodules alias was added in ccdd3da652 ("clone: Add the --recurse-submodules option as alias for --recursive", 2010-11-04). Since bb62e0a99f ("clone: teach --recurse-submodules to optionally take a pathspec", 2017-03-17) the longer form has been promoted to the default. But due to the way the options parsing machinery works this resulted in the rather absurd situation of: $ git clone --recurs [...] error: ambiguous option: recurs (could be --recursive or --recurse-submodules) Add OPT_ALIAS() to express this link between two or more options and use it in git-clone. Multiple aliases of an option could be written as OPT_ALIAS(0, "alias1", "original-name"), OPT_ALIAS(0, "alias2", "original-name"), ... The current implementation is not exactly optimal in this case. But we can optimize it when it becomes a problem. So far we don't even have two aliases of any option. A big chunk of code is actually from Junio C Hamano. Signed-off-by: Nguyễn Thái Ngọc Duy Signed-off-by: Junio C Hamano --- parse-options.c | 143 +++++++++++++++++++++++++++++++++++++++++++++++++++++--- 1 file changed, 137 insertions(+), 6 deletions(-) (limited to 'parse-options.c') diff --git a/parse-options.c b/parse-options.c index cb24f1aa8a..987e27cb91 100644 --- a/parse-options.c +++ b/parse-options.c @@ -261,6 +261,35 @@ static enum parse_opt_result parse_short_opt(struct parse_opt_ctx_t *p, return PARSE_OPT_UNKNOWN; } +static int has_string(const char *it, const char **array) +{ + while (*array) + if (!strcmp(it, *(array++))) + return 1; + return 0; +} + +static int is_alias(struct parse_opt_ctx_t *ctx, + const struct option *one_opt, + const struct option *another_opt) +{ + const char **group; + + if (!ctx->alias_groups) + return 0; + + if (!one_opt->long_name || !another_opt->long_name) + return 0; + + for (group = ctx->alias_groups; *group; group += 3) { + /* it and other are from the same family? */ + if (has_string(one_opt->long_name, group) && + has_string(another_opt->long_name, group)) + return 1; + } + return 0; +} + static enum parse_opt_result parse_long_opt( struct parse_opt_ctx_t *p, const char *arg, const struct option *options) @@ -298,7 +327,8 @@ again: if (!(p->flags & PARSE_OPT_KEEP_UNKNOWN) && !strncmp(long_name, arg, arg_end - arg)) { is_abbreviated: - if (abbrev_option) { + if (abbrev_option && + !is_alias(p, abbrev_option, options)) { /* * If this is abbreviated, it is * ambiguous. So when there is no @@ -447,6 +477,10 @@ static void parse_options_check(const struct option *opts) if (opts->callback) BUG("OPTION_LOWLEVEL_CALLBACK needs no high level callback"); break; + case OPTION_ALIAS: + BUG("OPT_ALIAS() should not remain at this point. " + "Are you using parse_options_step() directly?\n" + "That case is not supported yet."); default: ; /* ok. (usually accepts an argument) */ } @@ -458,11 +492,10 @@ static void parse_options_check(const struct option *opts) exit(128); } -void parse_options_start(struct parse_opt_ctx_t *ctx, - int argc, const char **argv, const char *prefix, - const struct option *options, int flags) +static void parse_options_start_1(struct parse_opt_ctx_t *ctx, + int argc, const char **argv, const char *prefix, + const struct option *options, int flags) { - memset(ctx, 0, sizeof(*ctx)); ctx->argc = argc; ctx->argv = argv; if (!(flags & PARSE_OPT_ONE_SHOT)) { @@ -484,6 +517,14 @@ void parse_options_start(struct parse_opt_ctx_t *ctx, parse_options_check(options); } +void parse_options_start(struct parse_opt_ctx_t *ctx, + int argc, const char **argv, const char *prefix, + const struct option *options, int flags) +{ + memset(ctx, 0, sizeof(*ctx)); + parse_options_start_1(ctx, argc, argv, prefix, options, flags); +} + static void show_negated_gitcomp(const struct option *opts, int nr_noopts) { int printed_dashdash = 0; @@ -575,6 +616,83 @@ static int show_gitcomp(const struct option *opts) return PARSE_OPT_COMPLETE; } +/* + * Scan and may produce a new option[] array, which should be used + * instead of the original 'options'. + * + * Right now this is only used to preprocess and substitue + * OPTION_ALIAS. + */ +static struct option *preprocess_options(struct parse_opt_ctx_t *ctx, + const struct option *options) +{ + struct option *newopt; + int i, nr, alias; + int nr_aliases = 0; + + for (nr = 0; options[nr].type != OPTION_END; nr++) { + if (options[nr].type == OPTION_ALIAS) + nr_aliases++; + } + + if (!nr_aliases) + return NULL; + + ALLOC_ARRAY(newopt, nr + 1); + COPY_ARRAY(newopt, options, nr + 1); + + /* each alias has two string pointers and NULL */ + CALLOC_ARRAY(ctx->alias_groups, 3 * (nr_aliases + 1)); + + for (alias = 0, i = 0; i < nr; i++) { + int short_name; + const char *long_name; + const char *source; + int j; + + if (newopt[i].type != OPTION_ALIAS) + continue; + + short_name = newopt[i].short_name; + long_name = newopt[i].long_name; + source = newopt[i].value; + + if (!long_name) + BUG("An alias must have long option name"); + + for (j = 0; j < nr; j++) { + const char *name = options[j].long_name; + + if (!name || strcmp(name, source)) + continue; + + if (options[j].type == OPTION_ALIAS) + BUG("No please. Nested aliases are not supported."); + + /* + * NEEDSWORK: this is a bit inconsistent because + * usage_with_options() on the original options[] will print + * help string as "alias of %s" but "git cmd -h" will + * print the original help string. + */ + memcpy(newopt + i, options + j, sizeof(*newopt)); + newopt[i].short_name = short_name; + newopt[i].long_name = long_name; + break; + } + + if (j == nr) + BUG("could not find source option '%s' of alias '%s'", + source, newopt[i].long_name); + ctx->alias_groups[alias * 3 + 0] = newopt[i].long_name; + ctx->alias_groups[alias * 3 + 1] = options[j].long_name; + ctx->alias_groups[alias * 3 + 2] = NULL; + alias++; + } + + return newopt; +} + static int usage_with_options_internal(struct parse_opt_ctx_t *, const char * const *, const struct option *, int, int); @@ -714,11 +832,16 @@ int parse_options(int argc, const char **argv, const char *prefix, int flags) { struct parse_opt_ctx_t ctx; + struct option *real_options; disallow_abbreviated_options = git_env_bool("GIT_TEST_DISALLOW_ABBREVIATED_OPTIONS", 0); - parse_options_start(&ctx, argc, argv, prefix, options, flags); + memset(&ctx, 0, sizeof(ctx)); + real_options = preprocess_options(&ctx, options); + if (real_options) + options = real_options; + parse_options_start_1(&ctx, argc, argv, prefix, options, flags); switch (parse_options_step(&ctx, options, usagestr)) { case PARSE_OPT_HELP: case PARSE_OPT_ERROR: @@ -741,6 +864,8 @@ int parse_options(int argc, const char **argv, const char *prefix, } precompose_argv(argc, argv); + free(real_options); + free(ctx.alias_groups); return parse_options_end(&ctx); } @@ -835,6 +960,12 @@ static int usage_with_options_internal(struct parse_opt_ctx_t *ctx, fputc('\n', outfile); pad = USAGE_OPTS_WIDTH; } + if (opts->type == OPTION_ALIAS) { + fprintf(outfile, "%*s", pad + USAGE_GAP, ""); + fprintf_ln(outfile, _("alias of --%s"), + (const char *)opts->value); + continue; + } fprintf(outfile, "%*s%s\n", pad + USAGE_GAP, "", _(opts->help)); } fputc('\n', outfile); -- cgit v1.2.1