git/parse-options.c
Jeff King cf4fff579e refactor skip_prefix to return a boolean
The skip_prefix() function returns a pointer to the content
past the prefix, or NULL if the prefix was not found. While
this is nice and simple, in practice it makes it hard to use
for two reasons:

  1. When you want to conditionally skip or keep the string
     as-is, you have to introduce a temporary variable.
     For example:

       tmp = skip_prefix(buf, "foo");
       if (tmp)
	       buf = tmp;

  2. It is verbose to check the outcome in a conditional, as
     you need extra parentheses to silence compiler
     warnings. For example:

       if ((cp = skip_prefix(buf, "foo"))
	       /* do something with cp */

Both of these make it harder to use for long if-chains, and
we tend to use starts_with() instead. However, the first line
of "do something" is often to then skip forward in buf past
the prefix, either using a magic constant or with an extra
strlen(3) (which is generally computed at compile time, but
means we are repeating ourselves).

This patch refactors skip_prefix() to return a simple boolean,
and to provide the pointer value as an out-parameter. If the
prefix is not found, the out-parameter is untouched. This
lets you write:

  if (skip_prefix(arg, "foo ", &arg))
	  do_foo(arg);
  else if (skip_prefix(arg, "bar ", &arg))
	  do_bar(arg);

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2014-06-20 10:44:43 -07:00

646 lines
17 KiB
C

#include "git-compat-util.h"
#include "parse-options.h"
#include "cache.h"
#include "commit.h"
#include "color.h"
#include "utf8.h"
static int parse_options_usage(struct parse_opt_ctx_t *ctx,
const char * const *usagestr,
const struct option *opts, int err);
#define OPT_SHORT 1
#define OPT_UNSET 2
int optbug(const struct option *opt, const char *reason)
{
if (opt->long_name)
return error("BUG: option '%s' %s", opt->long_name, reason);
return error("BUG: switch '%c' %s", opt->short_name, reason);
}
static int get_arg(struct parse_opt_ctx_t *p, const struct option *opt,
int flags, const char **arg)
{
if (p->opt) {
*arg = p->opt;
p->opt = NULL;
} else if (p->argc == 1 && (opt->flags & PARSE_OPT_LASTARG_DEFAULT)) {
*arg = (const char *)opt->defval;
} else if (p->argc > 1) {
p->argc--;
*arg = *++p->argv;
} else
return opterror(opt, "requires a value", flags);
return 0;
}
static void fix_filename(const char *prefix, const char **file)
{
if (!file || !*file || !prefix || is_absolute_path(*file)
|| !strcmp("-", *file))
return;
*file = xstrdup(prefix_filename(prefix, strlen(prefix), *file));
}
static int opt_command_mode_error(const struct option *opt,
const struct option *all_opts,
int flags)
{
const struct option *that;
struct strbuf message = STRBUF_INIT;
struct strbuf that_name = STRBUF_INIT;
/*
* Find the other option that was used to set the variable
* already, and report that this is not compatible with it.
*/
for (that = all_opts; that->type != OPTION_END; that++) {
if (that == opt ||
that->type != OPTION_CMDMODE ||
that->value != opt->value ||
that->defval != *(int *)opt->value)
continue;
if (that->long_name)
strbuf_addf(&that_name, "--%s", that->long_name);
else
strbuf_addf(&that_name, "-%c", that->short_name);
strbuf_addf(&message, ": incompatible with %s", that_name.buf);
strbuf_release(&that_name);
opterror(opt, message.buf, flags);
strbuf_release(&message);
return -1;
}
return opterror(opt, ": incompatible with something else", flags);
}
static int get_value(struct parse_opt_ctx_t *p,
const struct option *opt,
const struct option *all_opts,
int flags)
{
const char *s, *arg;
const int unset = flags & OPT_UNSET;
int err;
if (unset && p->opt)
return opterror(opt, "takes no value", flags);
if (unset && (opt->flags & PARSE_OPT_NONEG))
return opterror(opt, "isn't available", flags);
if (!(flags & OPT_SHORT) && p->opt && (opt->flags & PARSE_OPT_NOARG))
return opterror(opt, "takes no value", flags);
switch (opt->type) {
case OPTION_LOWLEVEL_CALLBACK:
return (*(parse_opt_ll_cb *)opt->callback)(p, opt, unset);
case OPTION_BIT:
if (unset)
*(int *)opt->value &= ~opt->defval;
else
*(int *)opt->value |= opt->defval;
return 0;
case OPTION_NEGBIT:
if (unset)
*(int *)opt->value |= opt->defval;
else
*(int *)opt->value &= ~opt->defval;
return 0;
case OPTION_COUNTUP:
*(int *)opt->value = unset ? 0 : *(int *)opt->value + 1;
return 0;
case OPTION_SET_INT:
*(int *)opt->value = unset ? 0 : opt->defval;
return 0;
case OPTION_CMDMODE:
/*
* Giving the same mode option twice, although is unnecessary,
* is not a grave error, so let it pass.
*/
if (*(int *)opt->value && *(int *)opt->value != opt->defval)
return opt_command_mode_error(opt, all_opts, flags);
*(int *)opt->value = opt->defval;
return 0;
case OPTION_STRING:
if (unset)
*(const char **)opt->value = NULL;
else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
*(const char **)opt->value = (const char *)opt->defval;
else
return get_arg(p, opt, flags, (const char **)opt->value);
return 0;
case OPTION_FILENAME:
err = 0;
if (unset)
*(const char **)opt->value = NULL;
else if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
*(const char **)opt->value = (const char *)opt->defval;
else
err = get_arg(p, opt, flags, (const char **)opt->value);
if (!err)
fix_filename(p->prefix, (const char **)opt->value);
return err;
case OPTION_CALLBACK:
if (unset)
return (*opt->callback)(opt, NULL, 1) ? (-1) : 0;
if (opt->flags & PARSE_OPT_NOARG)
return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
if (opt->flags & PARSE_OPT_OPTARG && !p->opt)
return (*opt->callback)(opt, NULL, 0) ? (-1) : 0;
if (get_arg(p, opt, flags, &arg))
return -1;
return (*opt->callback)(opt, arg, 0) ? (-1) : 0;
case OPTION_INTEGER:
if (unset) {
*(int *)opt->value = 0;
return 0;
}
if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
*(int *)opt->value = opt->defval;
return 0;
}
if (get_arg(p, opt, flags, &arg))
return -1;
*(int *)opt->value = strtol(arg, (char **)&s, 10);
if (*s)
return opterror(opt, "expects a numerical value", flags);
return 0;
default:
die("should not happen, someone must be hit on the forehead");
}
}
static int parse_short_opt(struct parse_opt_ctx_t *p, const struct option *options)
{
const struct option *all_opts = options;
const struct option *numopt = NULL;
for (; options->type != OPTION_END; options++) {
if (options->short_name == *p->opt) {
p->opt = p->opt[1] ? p->opt + 1 : NULL;
return get_value(p, options, all_opts, OPT_SHORT);
}
/*
* Handle the numerical option later, explicit one-digit
* options take precedence over it.
*/
if (options->type == OPTION_NUMBER)
numopt = options;
}
if (numopt && isdigit(*p->opt)) {
size_t len = 1;
char *arg;
int rc;
while (isdigit(p->opt[len]))
len++;
arg = xmemdupz(p->opt, len);
p->opt = p->opt[len] ? p->opt + len : NULL;
rc = (*numopt->callback)(numopt, arg, 0) ? (-1) : 0;
free(arg);
return rc;
}
return -2;
}
static int parse_long_opt(struct parse_opt_ctx_t *p, const char *arg,
const struct option *options)
{
const struct option *all_opts = options;
const char *arg_end = strchrnul(arg, '=');
const struct option *abbrev_option = NULL, *ambiguous_option = NULL;
int abbrev_flags = 0, ambiguous_flags = 0;
for (; options->type != OPTION_END; options++) {
const char *rest, *long_name = options->long_name;
int flags = 0, opt_flags = 0;
if (!long_name)
continue;
again:
if (!skip_prefix(arg, long_name, &rest))
rest = NULL;
if (options->type == OPTION_ARGUMENT) {
if (!rest)
continue;
if (*rest == '=')
return opterror(options, "takes no value", flags);
if (*rest)
continue;
p->out[p->cpidx++] = arg - 2;
return 0;
}
if (!rest) {
/* abbreviated? */
if (!strncmp(long_name, arg, arg_end - arg)) {
is_abbreviated:
if (abbrev_option) {
/*
* If this is abbreviated, it is
* ambiguous. So when there is no
* exact match later, we need to
* error out.
*/
ambiguous_option = abbrev_option;
ambiguous_flags = abbrev_flags;
}
if (!(flags & OPT_UNSET) && *arg_end)
p->opt = arg_end + 1;
abbrev_option = options;
abbrev_flags = flags ^ opt_flags;
continue;
}
/* negation allowed? */
if (options->flags & PARSE_OPT_NONEG)
continue;
/* negated and abbreviated very much? */
if (starts_with("no-", arg)) {
flags |= OPT_UNSET;
goto is_abbreviated;
}
/* negated? */
if (!starts_with(arg, "no-")) {
if (starts_with(long_name, "no-")) {
long_name += 3;
opt_flags |= OPT_UNSET;
goto again;
}
continue;
}
flags |= OPT_UNSET;
if (!skip_prefix(arg + 3, long_name, &rest)) {
/* abbreviated and negated? */
if (starts_with(long_name, arg + 3))
goto is_abbreviated;
else
continue;
}
}
if (*rest) {
if (*rest != '=')
continue;
p->opt = rest + 1;
}
return get_value(p, options, all_opts, flags ^ opt_flags);
}
if (ambiguous_option)
return error("Ambiguous option: %s "
"(could be --%s%s or --%s%s)",
arg,
(ambiguous_flags & OPT_UNSET) ? "no-" : "",
ambiguous_option->long_name,
(abbrev_flags & OPT_UNSET) ? "no-" : "",
abbrev_option->long_name);
if (abbrev_option)
return get_value(p, abbrev_option, all_opts, abbrev_flags);
return -2;
}
static int parse_nodash_opt(struct parse_opt_ctx_t *p, const char *arg,
const struct option *options)
{
const struct option *all_opts = options;
for (; options->type != OPTION_END; options++) {
if (!(options->flags & PARSE_OPT_NODASH))
continue;
if (options->short_name == arg[0] && arg[1] == '\0')
return get_value(p, options, all_opts, OPT_SHORT);
}
return -2;
}
static void check_typos(const char *arg, const struct option *options)
{
if (strlen(arg) < 3)
return;
if (starts_with(arg, "no-")) {
error ("did you mean `--%s` (with two dashes ?)", arg);
exit(129);
}
for (; options->type != OPTION_END; options++) {
if (!options->long_name)
continue;
if (starts_with(options->long_name, arg)) {
error ("did you mean `--%s` (with two dashes ?)", arg);
exit(129);
}
}
}
static void parse_options_check(const struct option *opts)
{
int err = 0;
for (; opts->type != OPTION_END; opts++) {
if ((opts->flags & PARSE_OPT_LASTARG_DEFAULT) &&
(opts->flags & PARSE_OPT_OPTARG))
err |= optbug(opts, "uses incompatible flags "
"LASTARG_DEFAULT and OPTARG");
if (opts->flags & PARSE_OPT_NODASH &&
((opts->flags & PARSE_OPT_OPTARG) ||
!(opts->flags & PARSE_OPT_NOARG) ||
!(opts->flags & PARSE_OPT_NONEG) ||
opts->long_name))
err |= optbug(opts, "uses feature "
"not supported for dashless options");
switch (opts->type) {
case OPTION_COUNTUP:
case OPTION_BIT:
case OPTION_NEGBIT:
case OPTION_SET_INT:
case OPTION_NUMBER:
if ((opts->flags & PARSE_OPT_OPTARG) ||
!(opts->flags & PARSE_OPT_NOARG))
err |= optbug(opts, "should not accept an argument");
default:
; /* ok. (usually accepts an argument) */
}
if (opts->argh &&
strcspn(opts->argh, " _") != strlen(opts->argh))
err |= optbug(opts, "multi-word argh should use dash to separate words");
}
if (err)
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)
{
memset(ctx, 0, sizeof(*ctx));
ctx->argc = argc - 1;
ctx->argv = argv + 1;
ctx->out = argv;
ctx->prefix = prefix;
ctx->cpidx = ((flags & PARSE_OPT_KEEP_ARGV0) != 0);
ctx->flags = flags;
if ((flags & PARSE_OPT_KEEP_UNKNOWN) &&
(flags & PARSE_OPT_STOP_AT_NON_OPTION))
die("STOP_AT_NON_OPTION and KEEP_UNKNOWN don't go together");
parse_options_check(options);
}
static int usage_with_options_internal(struct parse_opt_ctx_t *,
const char * const *,
const struct option *, int, int);
int parse_options_step(struct parse_opt_ctx_t *ctx,
const struct option *options,
const char * const usagestr[])
{
int internal_help = !(ctx->flags & PARSE_OPT_NO_INTERNAL_HELP);
/* we must reset ->opt, unknown short option leave it dangling */
ctx->opt = NULL;
for (; ctx->argc; ctx->argc--, ctx->argv++) {
const char *arg = ctx->argv[0];
if (*arg != '-' || !arg[1]) {
if (parse_nodash_opt(ctx, arg, options) == 0)
continue;
if (ctx->flags & PARSE_OPT_STOP_AT_NON_OPTION)
return PARSE_OPT_NON_OPTION;
ctx->out[ctx->cpidx++] = ctx->argv[0];
continue;
}
if (arg[1] != '-') {
ctx->opt = arg + 1;
if (internal_help && *ctx->opt == 'h')
return parse_options_usage(ctx, usagestr, options, 0);
switch (parse_short_opt(ctx, options)) {
case -1:
return parse_options_usage(ctx, usagestr, options, 1);
case -2:
if (ctx->opt)
check_typos(arg + 1, options);
goto unknown;
}
if (ctx->opt)
check_typos(arg + 1, options);
while (ctx->opt) {
if (internal_help && *ctx->opt == 'h')
return parse_options_usage(ctx, usagestr, options, 0);
switch (parse_short_opt(ctx, options)) {
case -1:
return parse_options_usage(ctx, usagestr, options, 1);
case -2:
/* fake a short option thing to hide the fact that we may have
* started to parse aggregated stuff
*
* This is leaky, too bad.
*/
ctx->argv[0] = xstrdup(ctx->opt - 1);
*(char *)ctx->argv[0] = '-';
goto unknown;
}
}
continue;
}
if (!arg[2]) { /* "--" */
if (!(ctx->flags & PARSE_OPT_KEEP_DASHDASH)) {
ctx->argc--;
ctx->argv++;
}
break;
}
if (internal_help && !strcmp(arg + 2, "help-all"))
return usage_with_options_internal(ctx, usagestr, options, 1, 0);
if (internal_help && !strcmp(arg + 2, "help"))
return parse_options_usage(ctx, usagestr, options, 0);
switch (parse_long_opt(ctx, arg + 2, options)) {
case -1:
return parse_options_usage(ctx, usagestr, options, 1);
case -2:
goto unknown;
}
continue;
unknown:
if (!(ctx->flags & PARSE_OPT_KEEP_UNKNOWN))
return PARSE_OPT_UNKNOWN;
ctx->out[ctx->cpidx++] = ctx->argv[0];
ctx->opt = NULL;
}
return PARSE_OPT_DONE;
}
int parse_options_end(struct parse_opt_ctx_t *ctx)
{
memmove(ctx->out + ctx->cpidx, ctx->argv, ctx->argc * sizeof(*ctx->out));
ctx->out[ctx->cpidx + ctx->argc] = NULL;
return ctx->cpidx + ctx->argc;
}
int parse_options(int argc, const char **argv, const char *prefix,
const struct option *options, const char * const usagestr[],
int flags)
{
struct parse_opt_ctx_t ctx;
parse_options_start(&ctx, argc, argv, prefix, options, flags);
switch (parse_options_step(&ctx, options, usagestr)) {
case PARSE_OPT_HELP:
exit(129);
case PARSE_OPT_NON_OPTION:
case PARSE_OPT_DONE:
break;
default: /* PARSE_OPT_UNKNOWN */
if (ctx.argv[0][1] == '-') {
error("unknown option `%s'", ctx.argv[0] + 2);
} else if (isascii(*ctx.opt)) {
error("unknown switch `%c'", *ctx.opt);
} else {
error("unknown non-ascii option in string: `%s'",
ctx.argv[0]);
}
usage_with_options(usagestr, options);
}
precompose_argv(argc, argv);
return parse_options_end(&ctx);
}
static int usage_argh(const struct option *opts, FILE *outfile)
{
const char *s;
int literal = (opts->flags & PARSE_OPT_LITERAL_ARGHELP) || !opts->argh;
if (opts->flags & PARSE_OPT_OPTARG)
if (opts->long_name)
s = literal ? "[=%s]" : "[=<%s>]";
else
s = literal ? "[%s]" : "[<%s>]";
else
s = literal ? " %s" : " <%s>";
return utf8_fprintf(outfile, s, opts->argh ? _(opts->argh) : _("..."));
}
#define USAGE_OPTS_WIDTH 24
#define USAGE_GAP 2
static int usage_with_options_internal(struct parse_opt_ctx_t *ctx,
const char * const *usagestr,
const struct option *opts, int full, int err)
{
FILE *outfile = err ? stderr : stdout;
if (!usagestr)
return PARSE_OPT_HELP;
if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
fprintf(outfile, "cat <<\\EOF\n");
fprintf_ln(outfile, _("usage: %s"), _(*usagestr++));
while (*usagestr && **usagestr)
/* TRANSLATORS: the colon here should align with the
one in "usage: %s" translation */
fprintf_ln(outfile, _(" or: %s"), _(*usagestr++));
while (*usagestr) {
if (**usagestr)
fprintf_ln(outfile, _(" %s"), _(*usagestr));
else
putchar('\n');
usagestr++;
}
if (opts->type != OPTION_GROUP)
fputc('\n', outfile);
for (; opts->type != OPTION_END; opts++) {
size_t pos;
int pad;
if (opts->type == OPTION_GROUP) {
fputc('\n', outfile);
if (*opts->help)
fprintf(outfile, "%s\n", _(opts->help));
continue;
}
if (!full && (opts->flags & PARSE_OPT_HIDDEN))
continue;
pos = fprintf(outfile, " ");
if (opts->short_name) {
if (opts->flags & PARSE_OPT_NODASH)
pos += fprintf(outfile, "%c", opts->short_name);
else
pos += fprintf(outfile, "-%c", opts->short_name);
}
if (opts->long_name && opts->short_name)
pos += fprintf(outfile, ", ");
if (opts->long_name)
pos += fprintf(outfile, "--%s", opts->long_name);
if (opts->type == OPTION_NUMBER)
pos += utf8_fprintf(outfile, _("-NUM"));
if ((opts->flags & PARSE_OPT_LITERAL_ARGHELP) ||
!(opts->flags & PARSE_OPT_NOARG))
pos += usage_argh(opts, outfile);
if (pos <= USAGE_OPTS_WIDTH)
pad = USAGE_OPTS_WIDTH - pos;
else {
fputc('\n', outfile);
pad = USAGE_OPTS_WIDTH;
}
fprintf(outfile, "%*s%s\n", pad + USAGE_GAP, "", _(opts->help));
}
fputc('\n', outfile);
if (!err && ctx && ctx->flags & PARSE_OPT_SHELL_EVAL)
fputs("EOF\n", outfile);
return PARSE_OPT_HELP;
}
void NORETURN usage_with_options(const char * const *usagestr,
const struct option *opts)
{
usage_with_options_internal(NULL, usagestr, opts, 0, 1);
exit(129);
}
void NORETURN usage_msg_opt(const char *msg,
const char * const *usagestr,
const struct option *options)
{
fprintf(stderr, "%s\n\n", msg);
usage_with_options(usagestr, options);
}
static int parse_options_usage(struct parse_opt_ctx_t *ctx,
const char * const *usagestr,
const struct option *opts, int err)
{
return usage_with_options_internal(ctx, usagestr, opts, 0, err);
}
#undef opterror
int opterror(const struct option *opt, const char *reason, int flags)
{
if (flags & OPT_SHORT)
return error("switch `%c' %s", opt->short_name, reason);
if (flags & OPT_UNSET)
return error("option `no-%s' %s", opt->long_name, reason);
return error("option `%s' %s", opt->long_name, reason);
}