git/parse-options.c
Jeff King e4da43b1f0 prefix_filename: return newly allocated string
The prefix_filename() function returns a pointer to static
storage, which makes it easy to use dangerously. We already
fixed one buggy caller in hash-object recently, and the
calls in apply.c are suspicious (I didn't dig in enough to
confirm that there is a bug, but we call the function once
in apply_all_patches() and then again indirectly from
parse_chunk()).

Let's make it harder to get wrong by allocating the return
value. For simplicity, we'll do this even when the prefix is
empty (and we could just return the original file pointer).
That will cause us to allocate sometimes when we wouldn't
otherwise need to, but this function isn't called in
performance critical code-paths (and it already _might_
allocate on any given call, so a caller that cares about
performance is questionable anyway).

The downside is that the callers need to remember to free()
the result to avoid leaking. Most of them already used
xstrdup() on the result, so we know they are OK. The
remainder have been converted to use free() as appropriate.

I considered retaining a prefix_filename_unsafe() for cases
where we know the static lifetime is OK (and handling the
cleanup is awkward). This is only a handful of cases,
though, and it's not worth the mental energy in worrying
about whether the "unsafe" variant is OK to use in any
situation.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2017-03-21 11:18:41 -07:00

677 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"
#define OPT_SHORT 1
#define OPT_UNSET 2
int optbug(const struct option *opt, const char *reason)
{
if (opt->long_name) {
if (opt->short_name)
return error("BUG: switch '%c' (--%s) %s",
opt->short_name, opt->long_name, reason);
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 = prefix_filename(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:
if (*(int *)opt->value < 0)
*(int *)opt->value = 0;
*(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;
case OPTION_MAGNITUDE:
if (unset) {
*(unsigned long *)opt->value = 0;
return 0;
}
if (opt->flags & PARSE_OPT_OPTARG && !p->opt) {
*(unsigned long *)opt->value = opt->defval;
return 0;
}
if (get_arg(p, opt, flags, &arg))
return -1;
if (!git_parse_ulong(arg, opt->value))
return opterror(opt,
"expects a non-negative integer value with an optional k/m/g suffix",
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;
char short_opts[128];
memset(short_opts, '\0', sizeof(short_opts));
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->short_name) {
if (0x7F <= opts->short_name)
err |= optbug(opts, "invalid short name");
else if (short_opts[opts->short_name]++)
err |= optbug(opts, "short name already used");
}
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 = ctx->total = 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);
int err = 0;
/* 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;
}
/* lone -h asks for help */
if (internal_help && ctx->total == 1 && !strcmp(arg + 1, "h"))
goto show_usage;
if (arg[1] != '-') {
ctx->opt = arg + 1;
switch (parse_short_opt(ctx, options)) {
case -1:
goto show_usage_error;
case -2:
if (ctx->opt)
check_typos(arg + 1, options);
if (internal_help && *ctx->opt == 'h')
goto show_usage;
goto unknown;
}
if (ctx->opt)
check_typos(arg + 1, options);
while (ctx->opt) {
switch (parse_short_opt(ctx, options)) {
case -1:
goto show_usage_error;
case -2:
if (internal_help && *ctx->opt == 'h')
goto show_usage;
/* 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"))
goto show_usage;
switch (parse_long_opt(ctx, arg + 2, options)) {
case -1:
goto show_usage_error;
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;
show_usage_error:
err = 1;
show_usage:
return usage_with_options_internal(ctx, usagestr, options, 0, err);
}
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, "fatal: %s\n\n", msg);
usage_with_options(usagestr, options);
}
#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);
}