This enables the usage of the stream APIs with arbitrary filedescriptors.

It will be used by a future testcase.

Signed-off-by: Thomas Weißschuh linux@weissschuh.net

---

Willy:

This uses intptr_t instead of uintptr_t as proposed because uintptr_t can not be negative. --- tools/include/nolibc/stdio.h | 95 +++++++++++++++++++++++++++++++------------- 1 file changed, 68 insertions(+), 27 deletions(-)

diff --git a/tools/include/nolibc/stdio.h b/tools/include/nolibc/stdio.h index 96ac8afc5aee..4add736c07aa 100644 --- a/tools/include/nolibc/stdio.h +++ b/tools/include/nolibc/stdio.h @@ -21,17 +21,75 @@ #define EOF (-1) #endif

-/* just define FILE as a non-empty type */ +/* just define FILE as a non-empty type. The value of the pointer gives + * the FD: FILE=~fd for fd>=0 or NULL for fd<0. This way positive FILE + * are immediately identified as abnormal entries (i.e. possible copies + * of valid pointers to something else). + */ typedef struct FILE { char dummy[1]; } FILE;

-/* We define the 3 common stdio files as constant invalid pointers that - * are easily recognized. - */ -static __attribute__((unused)) FILE* const stdin = (FILE*)-3; -static __attribute__((unused)) FILE* const stdout = (FILE*)-2; -static __attribute__((unused)) FILE* const stderr = (FILE*)-1; +static __attribute__((unused)) FILE* const stdin = (FILE*)(intptr_t)~STDIN_FILENO; +static __attribute__((unused)) FILE* const stdout = (FILE*)(intptr_t)~STDOUT_FILENO; +static __attribute__((unused)) FILE* const stderr = (FILE*)(intptr_t)~STDERR_FILENO; + +/* provides a FILE* equivalent of fd. The mode is ignored. */ +static __attribute__((unused)) +FILE *fdopen(int fd, const char *mode __attribute__((unused))) +{ + if (fd < 0) { + SET_ERRNO(EBADF); + return NULL; + } + return (FILE*)(intptr_t)~fd; +} + +/* provides the fd of stream. */ +static __attribute__((unused)) +int fileno(FILE *stream) +{ + intptr_t i = (intptr_t)stream; + + if (i >= 0) { + SET_ERRNO(EBADF); + return -1; + } + return ~i; +} + +/* flush a stream. */ +static __attribute__((unused)) +int fflush(FILE *stream) +{ + intptr_t i = (intptr_t)stream; + + /* NULL is valid here. */ + if (i > 0) { + SET_ERRNO(EBADF); + return -1; + } + + /* Don't do anything, nolibc does not support buffering. */ + return 0; +} + +/* flush a stream. */ +static __attribute__((unused)) +int fclose(FILE *stream) +{ + intptr_t i = (intptr_t)stream; + + if (i >= 0) { + SET_ERRNO(EBADF); + return -1; + } + + if (close(~i)) + return EOF; + + return 0; +}

/* getc(), fgetc(), getchar() */

@@ -41,14 +99,8 @@ static __attribute__((unused)) int fgetc(FILE* stream) { unsigned char ch; - int fd;

- if (stream < stdin || stream > stderr) - return EOF; - - fd = 3 + (long)stream; - - if (read(fd, &ch, 1) <= 0) + if (read(fileno(stream), &ch, 1) <= 0) return EOF; return ch; } @@ -68,14 +120,8 @@ static __attribute__((unused)) int fputc(int c, FILE* stream) { unsigned char ch = c; - int fd; - - if (stream < stdin || stream > stderr) - return EOF; - - fd = 3 + (long)stream;

- if (write(fd, &ch, 1) <= 0) + if (write(fileno(stream), &ch, 1) <= 0) return EOF; return ch; } @@ -96,12 +142,7 @@ static __attribute__((unused)) int _fwrite(const void *buf, size_t size, FILE *stream) { ssize_t ret; - int fd; - - if (stream < stdin || stream > stderr) - return EOF; - - fd = 3 + (long)stream; + int fd = fileno(stream);

while (size) { ret = write(fd, buf, size);

vfprintf() is complex and so far did not have proper tests.

Signed-off-by: Thomas Weißschuh linux@weissschuh.net --- tools/testing/selftests/nolibc/nolibc-test.c | 86 ++++++++++++++++++++++++++++ 1 file changed, 86 insertions(+)

diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c index 47013b78972e..de943e028933 100644 --- a/tools/testing/selftests/nolibc/nolibc-test.c +++ b/tools/testing/selftests/nolibc/nolibc-test.c @@ -20,6 +20,7 @@ #include <linux/reboot.h> #include <sys/io.h> #include <sys/ioctl.h> +#include <sys/mman.h> #include <sys/mount.h> #include <sys/reboot.h> #include <sys/stat.h> @@ -667,6 +668,90 @@ int run_stdlib(int min, int max) return ret; }

+#define EXPECT_VFPRINTF(c, expected, fmt, ...) \ + ret += expect_vfprintf(llen, c, expected, fmt, ##__VA_ARGS__) + +static int expect_vfprintf(int llen, size_t c, const char *expected, const char *fmt, ...) +{ + int ret, fd, w, r; + char buf[100]; + FILE *memfile; + va_list args; + + fd = memfd_create("vfprintf", 0); + if (fd == -1) { + pad_spc(llen, 64, "[FAIL]\n"); + return 1; + } + + memfile = fdopen(fd, "w+"); + if (!memfile) { + pad_spc(llen, 64, "[FAIL]\n"); + return 1; + } + + va_start(args, fmt); + w = vfprintf(memfile, fmt, args); + va_end(args); + + if (w != c) { + llen += printf(" written(%d) != %d", w, (int) c); + pad_spc(llen, 64, "[FAIL]\n"); + return 1; + } + + fflush(memfile); + lseek(fd, 0, SEEK_SET); + + r = read(fd, buf, sizeof(buf) - 1); + buf[r] = '\0'; + + fclose(memfile); + + if (r != w) { + llen += printf(" written(%d) != read(%d)", w, r); + pad_spc(llen, 64, "[FAIL]\n"); + return 1; + } + + llen += printf(" "%s" = "%s"", expected, buf); + ret = strncmp(expected, buf, c); + + pad_spc(llen, 64, ret ? "[FAIL]\n" : " [OK]\n"); + return ret; +} + +static int run_vfprintf(int min, int max) +{ + int test; + int tmp; + int ret = 0; + void *p1, *p2; + + for (test = min; test >= 0 && test <= max; test++) { + int llen = 0; // line length + + /* avoid leaving empty lines below, this will insert holes into + * test numbers. + */ + switch (test + __LINE__ + 1) { + CASE_TEST(empty); EXPECT_VFPRINTF(0, "", ""); break; + CASE_TEST(simple); EXPECT_VFPRINTF(3, "foo", "foo"); break; + CASE_TEST(string); EXPECT_VFPRINTF(3, "foo", "%s", "foo"); break; + CASE_TEST(number); EXPECT_VFPRINTF(4, "1234", "%d", 1234); break; + CASE_TEST(negnumber); EXPECT_VFPRINTF(5, "-1234", "%d", -1234); break; + CASE_TEST(unsigned); EXPECT_VFPRINTF(5, "12345", "%u", 12345); break; + CASE_TEST(char); EXPECT_VFPRINTF(1, "c", "%c", 'c'); break; + CASE_TEST(hex); EXPECT_VFPRINTF(1, "f", "%x", 0xf); break; + CASE_TEST(pointer); EXPECT_VFPRINTF(3, "0x1", "%p", (void *) 0x1); break; + case __LINE__: + return ret; /* must be last */ + /* note: do not set any defaults so as to permit holes above */ + } + } + return ret; +} + static int smash_stack(void) { char buf[100]; @@ -774,6 +859,7 @@ static const struct test test_names[] = { /* add new tests here */ { .name = "syscall", .func = run_syscall }, { .name = "stdlib", .func = run_stdlib }, + { .name = "vfprintf", .func = run_vfprintf }, { .name = "protection", .func = run_protection }, { 0 } };