From a009a0c6faa9e7ffac13d55ef6cdac1f9a68efbe Mon Sep 17 00:00:00 2001 From: Thomas Weißschuh Date: Mon, 28 Apr 2025 14:40:14 +0200 Subject: tools/nolibc: add fopen() MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit This is used in various selftests and will be handy when integrating those with nolibc. Only the standard POSIX modes are supported. No extensions nor the (noop) "b" from ISO C are accepted. Signed-off-by: Thomas Weißschuh Acked-by: Willy Tarreau Link: https://lore.kernel.org/r/20250428-nolibc-misc-v2-13-3c043eeab06c@linutronix.de Signed-off-by: Thomas Weißschuh --- tools/include/nolibc/stdio.h | 27 +++++++++++++++++++++++++++ tools/testing/selftests/nolibc/nolibc-test.c | 24 ++++++++++++++++++++++++ 2 files changed, 51 insertions(+) diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h index df5717d59182..c470d334ef3f 100644 --- a/tools/include/nolibc/stdio.h +++ b/tools/include/nolibc/stdio.h @@ -13,6 +13,7 @@ #include "std.h" #include "arch.h" #include "errno.h" +#include "fcntl.h" #include "types.h" #include "sys.h" #include "stdarg.h" @@ -55,6 +56,32 @@ FILE *fdopen(int fd, const char *mode __attribute__((unused))) return (FILE*)(intptr_t)~fd; } +static __attribute__((unused)) +FILE *fopen(const char *pathname, const char *mode) +{ + int flags, fd; + + switch (*mode) { + case 'r': + flags = O_RDONLY; + break; + case 'w': + flags = O_WRONLY | O_CREAT | O_TRUNC; + break; + case 'a': + flags = O_WRONLY | O_CREAT | O_APPEND; + break; + default: + SET_ERRNO(EINVAL); return NULL; + } + + if (mode[1] == '+') + flags = (flags & ~(O_RDONLY | O_WRONLY)) | O_RDWR; + + fd = open(pathname, flags, 0666); + return fdopen(fd, mode); +} + /* provides the fd of stream. */ static __attribute__((unused)) int fileno(FILE *stream) diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c index d1157319b5d7..0391c7d01380 100644 --- a/tools/testing/selftests/nolibc/nolibc-test.c +++ b/tools/testing/selftests/nolibc/nolibc-test.c @@ -859,6 +859,29 @@ int test_getpagesize(void) return !c; } +int test_file_stream(void) +{ + FILE *f; + int r; + + f = fopen("/dev/null", "r"); + if (!f) + return -1; + + errno = 0; + r = fwrite("foo", 1, 3, f); + if (r != 0 || errno != EBADF) { + fclose(f); + return -1; + } + + r = fclose(f); + if (r == EOF) + return -1; + + return 0; +} + int test_fork(void) { int status; @@ -1311,6 +1334,7 @@ int run_syscall(int min, int max) CASE_TEST(dup3_0); tmp = dup3(0, 100, 0); EXPECT_SYSNE(1, tmp, -1); close(tmp); break; CASE_TEST(dup3_m1); tmp = dup3(-1, 100, 0); EXPECT_SYSER(1, tmp, -1, EBADF); if (tmp != -1) close(tmp); break; CASE_TEST(execve_root); EXPECT_SYSER(1, execve("/", (char*[]){ [0] = "/", [1] = NULL }, NULL), -1, EACCES); break; + CASE_TEST(file_stream); EXPECT_SYSZR(1, test_file_stream()); break; CASE_TEST(fork); EXPECT_SYSZR(1, test_fork()); break; CASE_TEST(getdents64_root); EXPECT_SYSNE(1, test_getdents64("/"), -1); break; CASE_TEST(getdents64_null); EXPECT_SYSER(1, test_getdents64("/dev/null"), -1, ENOTDIR); break; -- cgit v1.2.3