From: Ammar Faizi ammarfaizi2@gnuweeb.org

Previous commits save the address of the auxiliary vector into a global variable @_auxv. This commit creates a new function 'getauxval()' as a helper function to get the auxv value based on the given key.

The behavior of this function is identic with the function documented in 'man 3 getauxval'. This function is also needed to implement 'getpagesize()' function that we will wire up in the next patches.

Signed-off-by: Ammar Faizi ammarfaizi2@gnuweeb.org --- tools/include/nolibc/stdlib.h | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+)

diff --git a/tools/include/nolibc/stdlib.h b/tools/include/nolibc/stdlib.h index 92378c4b9660..cdca557c4013 100644 --- a/tools/include/nolibc/stdlib.h +++ b/tools/include/nolibc/stdlib.h @@ -12,6 +12,7 @@ #include "types.h" #include "sys.h" #include "string.h" +#include <linux/auxvec.h>

struct nolibc_heap { size_t len; @@ -108,6 +109,32 @@ char *getenv(const char *name) return _getenv(name, environ); }

+static __attribute__((unused)) +unsigned long getauxval(unsigned long type) +{ + const unsigned long *auxv = _auxv; + unsigned long ret; + + if (!auxv) + return 0; + + while (1) { + if (!auxv[0] && !auxv[1]) { + ret = 0; + break; + } + + if (auxv[0] == type) { + ret = auxv[1]; + break; + } + + auxv += 2; + } + + return ret; +} + static __attribute__((unused)) void *malloc(size_t len) {

From: Ammar Faizi ammarfaizi2@gnuweeb.org

Test the getpagesize() function. Make sure it returns the correct value.

Signed-off-by: Ammar Faizi ammarfaizi2@gnuweeb.org --- tools/testing/selftests/nolibc/nolibc-test.c | 30 ++++++++++++++++++++ 1 file changed, 30 insertions(+)

diff --git a/tools/testing/selftests/nolibc/nolibc-test.c b/tools/testing/selftests/nolibc/nolibc-test.c index 6da17612251c..3a78399f4624 100644 --- a/tools/testing/selftests/nolibc/nolibc-test.c +++ b/tools/testing/selftests/nolibc/nolibc-test.c @@ -442,6 +442,35 @@ int test_getdents64(const char *dir) return ret; }

+static int test_getpagesize(void) +{ + long x = getpagesize(); + int c; + + if (x < 0) + return x; + +#if defined(__x86_64__) || defined(__i386__) || defined(__i486__) || defined(__i586__) || defined(__i686__) + /* + * x86 family is always 4K page. + */ + c = (x == 4096); +#elif defined(__aarch64__) + /* + * Linux aarch64 supports three values of page size: 4K, 16K, and 64K + * which are selected at kernel compilation time. + */ + c = (x == 4096 || x == (16 * 1024) || x == (64 * 1024)); +#else + /* + * Assuming other architectures must have at least 4K page. + */ + c = (x >= 4096); +#endif + + return !c; +} + /* Run syscall tests between IDs <min> and <max>. * Return 0 on success, non-zero on failure. */ @@ -502,6 +531,7 @@ int run_syscall(int min, int max) CASE_TEST(gettimeofday_bad2); EXPECT_SYSER(1, gettimeofday(NULL, (void *)1), -1, EFAULT); break; CASE_TEST(gettimeofday_bad2); EXPECT_SYSER(1, gettimeofday(NULL, (void *)1), -1, EFAULT); break; #endif + CASE_TEST(getpagesize); EXPECT_SYSZR(1, test_getpagesize()); break; CASE_TEST(ioctl_tiocinq); EXPECT_SYSZR(1, ioctl(0, TIOCINQ, &tmp)); break; CASE_TEST(ioctl_tiocinq); EXPECT_SYSZR(1, ioctl(0, TIOCINQ, &tmp)); break; CASE_TEST(link_root1); EXPECT_SYSER(1, link("/", "/"), -1, EEXIST); break;