musl: introduce wrappers for getopt() and getopt_long()

musl's getopt_long() behaves something different in handling optional arguments:
```
$ journalctl _PID=1 _COMM=systemd --since 19:19:01 -n all --follow
Failed to add match 'all': Invalid argument
```
This introduces getopt_long_fix() that reorders the passed arguments to make
getopt_long() provided by musl works as what we expect.

Also, musl's getopt() always behaves POSIXLY_CORRECT mode, and stops parsing
arguments when a non-option string found. Let's always use getopt_long().
This commit is contained in:
Yu Watanabe
2025-11-30 11:10:02 +09:00
committed by Zbigniew Jędrzejewski-Szmek
parent 26b2085d54
commit 53f5aa3fd2
6 changed files with 659 additions and 0 deletions

29
src/include/musl/getopt.h Normal file
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@@ -0,0 +1,29 @@
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
/* getopt() is provided both in getopt.h and unistd.h. Hence, we need to tentatively undefine it. */
#undef getopt
#include_next <getopt.h>
/* musl's getopt() always behaves POSIXLY_CORRECT mode, and stops parsing arguments when a non-option string
* found. Let's always use getopt_long(). */
int getopt_fix(int argc, char * const *argv, const char *optstring);
#define getopt(argc, argv, optstring) getopt_fix(argc, argv, optstring)
/* musl's getopt_long() behaves something different in handling optional arguments.
* ========
* $ journalctl _PID=1 _COMM=systemd --since 19:19:01 -n all --follow
* Failed to add match 'all': Invalid argument
* ========
* Here, we introduce getopt_long_fix() that reorders the passed arguments to make getopt_long() provided by
* musl works as what we expect. */
int getopt_long_fix(
int argc,
char * const *argv,
const char *optstring,
const struct option *longopts,
int *longindex);
#define getopt_long(argc, argv, optstring, longopts, longindex) \
getopt_long_fix(argc, argv, optstring, longopts, longindex)

12
src/include/musl/unistd.h Normal file
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@@ -0,0 +1,12 @@
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#pragma once
/* getopt() is provided both in getopt.h and unistd.h. Hence, we need to tentatively undefine it. */
#undef getopt
#include_next <unistd.h>
/* musl's getopt() always behaves POSIXLY_CORRECT mode, and stops parsing arguments when a non-option string
* found. Let's always use getopt_long(). */
int getopt_fix(int argc, char * const *argv, const char *optstring);
#define getopt(argc, argv, optstring) getopt_fix(argc, argv, optstring)

100
src/libc/musl/getopt.c Normal file
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@@ -0,0 +1,100 @@
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include <getopt.h>
#include <stdbool.h>
#include <string.h>
static int first_non_opt = 0, last_non_opt = 0;
static bool non_opt_found = false, dash_dash = false;
static void shift(char * const *argv, int start, int end) {
char **av = (char**) argv;
char *saved = av[end];
for (int i = end; i > start; i--)
av[i] = av[i - 1];
av[start] = saved;
}
static void exchange(int argc, char * const *argv) {
/* input:
*
* first_non_opt last_non_opt optind
* | | |
* v v v
* aaaaa bbbbb ccccc --prev-opt prev-opt-arg ddddd --next-opt
*
* output:
* first_non_opt last_non_opt optind
* | | |
* v v v
* --prev-opt prev-opt-arg aaaaa bbbbb ccccc ddddd --next-opt
*/
/* First, move previous arguments. */
int c = optind - 1 - last_non_opt;
if (c > 0) {
for (int i = 0; i < c; i++)
shift(argv, first_non_opt, optind - 1);
first_non_opt += c;
last_non_opt += c;
}
/* Then, skip entries that do not start with '-'. */
while (optind < argc && (argv[optind][0] != '-' || argv[optind][1] == '\0')) {
if (!non_opt_found) {
first_non_opt = optind;
non_opt_found = true;
}
last_non_opt = optind;
optind++;
}
}
int getopt_long_fix(
int argc,
char * const *argv,
const char *optstring,
const struct option *longopts,
int *longindex) {
int r;
if (optind == 0 || first_non_opt == 0 || last_non_opt == 0) {
/* initialize musl's internal variables. */
(void) (getopt_long)(/* argc= */ -1, /* argv= */ NULL, /* optstring= */ NULL, /* longopts= */ NULL, /* longindex= */ NULL);
first_non_opt = last_non_opt = 1;
non_opt_found = dash_dash = false;
}
if (first_non_opt >= argc || last_non_opt >= argc || optind > argc || dash_dash)
return -1;
/* Do not shuffle arguments when optstring starts with '+' or '-'. */
if (!optstring || optstring[0] == '+' || optstring[0] == '-')
return (getopt_long)(argc, argv, optstring, longopts, longindex);
exchange(argc, argv);
if (optind < argc && strcmp(argv[optind], "--") == 0) {
if (first_non_opt < optind)
shift(argv, first_non_opt, optind);
first_non_opt++;
optind++;
dash_dash = true;
if (non_opt_found)
optind = first_non_opt;
return -1;
}
r = (getopt_long)(argc, argv, optstring, longopts, longindex);
if (r < 0 && non_opt_found)
optind = first_non_opt;
return r;
}
int getopt_fix(int argc, char * const *argv, const char *optstring) {
return getopt_long_fix(argc, argv, optstring, /* longopts= */ NULL, /* longindex= */ NULL);
}

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@@ -5,6 +5,7 @@ if get_option('libc') != 'musl'
endif
libc_wrapper_sources += files(
'getopt.c',
'printf.c',
'stdio.c',
'stdlib.c',

View File

@@ -111,6 +111,7 @@ simple_tests += files(
'test-format-util.c',
'test-fs-util.c',
'test-fstab-util.c',
'test-getopt.c',
'test-glob-util.c',
'test-gpt.c',
'test-gunicode.c',

516
src/test/test-getopt.c Normal file
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@@ -0,0 +1,516 @@
/* SPDX-License-Identifier: LGPL-2.1-or-later */
#include <getopt.h>
#include "strv.h"
#include "tests.h"
typedef struct Entry {
int opt;
const char *argument;
const char *nextarg;
} Entry;
static void test_getopt_long_one(
char **argv,
const char *optstring,
const struct option *longopts,
const Entry *entries,
char **remaining) {
_cleanup_free_ char *joined = strv_join(argv, ", ");
log_debug("/* %s(%s) */", __func__, joined);
_cleanup_free_ char *saved_argv0 = NULL;
ASSERT_NOT_NULL(saved_argv0 = strdup(argv[0]));
int c, argc = strv_length(argv);
size_t i = 0, n_entries = 0;
for (const Entry *e = entries; e && e->opt != 0; e++)
n_entries++;
optind = 0;
while ((c = getopt_long(argc, argv, optstring, longopts, NULL)) >= 0) {
if (c < 0x100)
log_debug("%c: %s", c, strna(optarg));
else
log_debug("0x%x: %s", (unsigned) c, strna(optarg));
ASSERT_LT(i, n_entries);
ASSERT_EQ(c, entries[i].opt);
ASSERT_STREQ(optarg, entries[i].argument);
if (entries[i].nextarg)
ASSERT_STREQ(argv[optind], entries[i].nextarg);
i++;
}
ASSERT_EQ(i, n_entries);
ASSERT_LE(optind, argc);
ASSERT_EQ(argc - optind, (int) strv_length(remaining));
for (int j = optind; j < argc; j++)
ASSERT_STREQ(argv[j], remaining[j - optind]);
ASSERT_STREQ(argv[0], saved_argv0);
}
TEST(getopt_long) {
enum {
ARG_VERSION = 0x100,
ARG_REQUIRED,
ARG_OPTIONAL,
};
static const struct option options[] = {
{ "help", no_argument, NULL, 'h' },
{ "version" , no_argument, NULL, ARG_VERSION },
{ "required1", required_argument, NULL, 'r' },
{ "required2", required_argument, NULL, ARG_REQUIRED },
{ "optional1", optional_argument, NULL, 'o' },
{ "optional2", optional_argument, NULL, ARG_OPTIONAL },
{},
};
test_getopt_long_one(STRV_MAKE("arg0"),
"hr:o::", options,
NULL,
NULL);
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"string2",
"string3",
"string4"),
"hr:o::", options,
NULL,
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"--",
"string1",
"string2",
"string3",
"string4"),
"hr:o::", options,
NULL,
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"string2",
"--",
"string3",
"string4"),
"hr:o::", options,
NULL,
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"string2",
"string3",
"string4",
"--"),
"hr:o::", options,
NULL,
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"--help"),
"hr:o::", options,
(Entry[]) {
{ 'h', NULL },
{}
},
NULL);
test_getopt_long_one(STRV_MAKE("arg0",
"-h"),
"hr:o::", options,
(Entry[]) {
{ 'h', NULL },
{}
},
NULL);
test_getopt_long_one(STRV_MAKE("arg0",
"--help",
"string1",
"string2",
"string3",
"string4"),
"hr:o::", options,
(Entry[]) {
{ 'h', NULL },
{}
},
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"-h",
"string1",
"string2",
"string3",
"string4"),
"hr:o::", options,
(Entry[]) {
{ 'h', NULL },
{}
},
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"string2",
"--help",
"string3",
"string4"),
"hr:o::", options,
(Entry[]) {
{ 'h', NULL },
{}
},
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"string2",
"-h",
"string3",
"string4"),
"hr:o::", options,
(Entry[]) {
{ 'h', NULL },
{}
},
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"string2",
"string3",
"string4",
"--help"),
"hr:o::", options,
(Entry[]) {
{ 'h', NULL },
{}
},
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"string2",
"string3",
"string4",
"-h"),
"hr:o::", options,
(Entry[]) {
{ 'h', NULL },
{}
},
STRV_MAKE("string1",
"string2",
"string3",
"string4"));
test_getopt_long_one(STRV_MAKE("arg0",
"--required1", "reqarg1"),
"hr:o::", options,
(Entry[]) {
{ 'r', "reqarg1" },
{}
},
NULL);
test_getopt_long_one(STRV_MAKE("arg0",
"-r", "reqarg1"),
"hr:o::", options,
(Entry[]) {
{ 'r', "reqarg1" },
{}
},
NULL);
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"string2",
"-r", "reqarg1"),
"hr:o::", options,
(Entry[]) {
{ 'r', "reqarg1" },
{}
},
STRV_MAKE("string1",
"string2"));
test_getopt_long_one(STRV_MAKE("arg0",
"--optional1=optarg1"),
"hr:o::", options,
(Entry[]) {
{ 'o', "optarg1" },
{}
},
NULL);
test_getopt_long_one(STRV_MAKE("arg0",
"--optional1", "string1"),
"hr:o::", options,
(Entry[]) {
{ 'o', NULL, "string1" },
{}
},
STRV_MAKE("string1"));
test_getopt_long_one(STRV_MAKE("arg0",
"-ooptarg1"),
"hr:o::", options,
(Entry[]) {
{ 'o', "optarg1" },
{}
}, NULL);
test_getopt_long_one(STRV_MAKE("arg0",
"-o", "string1"),
"hr:o::", options,
(Entry[]) {
{ 'o', NULL, "string1" },
{}
},
STRV_MAKE("string1"));
test_getopt_long_one(STRV_MAKE("arg0",
"string1",
"--help",
"--version",
"string2",
"--required1", "reqarg1",
"--required2", "reqarg2",
"--required1=reqarg3",
"--required2=reqarg4",
"string3",
"--optional1", "string4",
"--optional2", "string5",
"--optional1=optarg1",
"--optional2=optarg2",
"-h",
"-r", "reqarg5",
"-rreqarg6",
"-ooptarg3",
"-o",
"string6",
"-o",
"-h",
"-o",
"--help",
"string7",
"-hooptarg4",
"-hrreqarg6",
"--",
"--help",
"--required1",
"--optional1"),
"hr:o::", options,
(Entry[]) {
{ 'h' },
{ ARG_VERSION },
{ 'r', "reqarg1" },
{ ARG_REQUIRED, "reqarg2" },
{ 'r', "reqarg3" },
{ ARG_REQUIRED, "reqarg4" },
{ 'o', NULL, "string4" },
{ ARG_OPTIONAL, NULL, "string5" },
{ 'o', "optarg1" },
{ ARG_OPTIONAL, "optarg2" },
{ 'h' },
{ 'r', "reqarg5" },
{ 'r', "reqarg6" },
{ 'o', "optarg3" },
{ 'o', NULL, "string6" },
{ 'o', NULL, "-h" },
{ 'h' },
{ 'o', NULL, "--help" },
{ 'h' },
{ 'h' },
{ 'o', "optarg4" },
{ 'h' },
{ 'r', "reqarg6" },
{}
},
STRV_MAKE("string1",
"string2",
"string3",
"string4",
"string5",
"string6",
"string7",
"--help",
"--required1",
"--optional1"));
}
static void test_getopt_one(
char **argv,
const char *optstring,
const Entry *entries,
char **remaining) {
_cleanup_free_ char *joined = strv_join(argv, ", ");
log_debug("/* %s(%s) */", __func__, joined);
_cleanup_free_ char *saved_argv0 = NULL;
ASSERT_NOT_NULL(saved_argv0 = strdup(argv[0]));
int c, argc = strv_length(argv);
size_t i = 0, n_entries = 0;
for (const Entry *e = entries; e && e->opt != 0; e++)
n_entries++;
optind = 0;
while ((c = getopt(argc, argv, optstring)) >= 0) {
log_debug("%c: %s", c, strna(optarg));
ASSERT_LT(i, n_entries);
ASSERT_EQ(c, entries[i].opt);
ASSERT_STREQ(optarg, entries[i].argument);
if (entries[i].nextarg)
ASSERT_STREQ(argv[optind], entries[i].nextarg);
i++;
}
ASSERT_EQ(i, n_entries);
ASSERT_LE(optind, argc);
ASSERT_EQ(argc - optind, (int) strv_length(remaining));
for (int j = optind; j < argc; j++)
ASSERT_STREQ(argv[j], remaining[j - optind]);
ASSERT_STREQ(argv[0], saved_argv0);
}
TEST(getopt) {
test_getopt_one(STRV_MAKE("arg0"),
"hr:o::",
NULL,
NULL);
test_getopt_one(STRV_MAKE("arg0",
"string1",
"string2"),
"hr:o::",
NULL,
STRV_MAKE("string1",
"string2"));
test_getopt_one(STRV_MAKE("arg0",
"-h"),
"hr:o::",
(Entry[]) {
{ 'h', NULL },
{}
},
NULL);
test_getopt_one(STRV_MAKE("arg0",
"-r", "reqarg1"),
"hr:o::",
(Entry[]) {
{ 'r', "reqarg1" },
{}
},
NULL);
test_getopt_one(STRV_MAKE("arg0",
"string1",
"string2",
"-r", "reqarg1"),
"hr:o::",
(Entry[]) {
{ 'r', "reqarg1" },
{}
},
STRV_MAKE("string1",
"string2"));
test_getopt_one(STRV_MAKE("arg0",
"-ooptarg1"),
"hr:o::",
(Entry[]) {
{ 'o', "optarg1" },
{}
},
NULL);
test_getopt_one(STRV_MAKE("arg0",
"-o", "string1"),
"hr:o::",
(Entry[]) {
{ 'o', NULL, "string1" },
{}
},
STRV_MAKE("string1"));
test_getopt_one(STRV_MAKE("arg0",
"string1",
"string2",
"string3",
"-h",
"-r", "reqarg5",
"-rreqarg6",
"-ooptarg3",
"-o",
"string6",
"-o",
"-h",
"-o",
"string7",
"-hooptarg4",
"-hrreqarg6"),
"hr:o::",
(Entry[]) {
{ 'h' },
{ 'r', "reqarg5" },
{ 'r', "reqarg6" },
{ 'o', "optarg3" },
{ 'o', NULL, "string6" },
{ 'o', NULL, "-h" },
{ 'h' },
{ 'o', NULL, "string7" },
{ 'h' },
{ 'o', "optarg4" },
{ 'h' },
{ 'r', "reqarg6" },
{}
},
STRV_MAKE("string1",
"string2",
"string3",
"string6",
"string7"));
}
DEFINE_TEST_MAIN(LOG_DEBUG);