First Commit

3rdparty/cpuinfo/src/arm/linux/hwcap.c

@@ -0,0 +1,154 @@
+#include <limits.h>
+#include <string.h>
+
+#include <dlfcn.h>
+#include <elf.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+#if CPUINFO_MOCK
+#include <cpuinfo-mock.h>
+#endif
+#include <arm/linux/api.h>
+#include <cpuinfo.h>
+#include <cpuinfo/log.h>
+
+#if CPUINFO_ARCH_ARM64 ||                                                     \
+	CPUINFO_ARCH_ARM && defined(__GLIBC__) && defined(__GLIBC_MINOR__) && \
+		(__GLIBC__ > 2 || __GLIBC__ == 2 && __GLIBC_MINOR__ >= 16)
+#include <sys/auxv.h>
+#else
+#define AT_HWCAP 16
+#define AT_HWCAP2 26
+#endif
+
+#if CPUINFO_MOCK
+static uint32_t mock_hwcap = 0;
+void cpuinfo_set_hwcap(uint32_t hwcap) {
+	mock_hwcap = hwcap;
+}
+
+static uint64_t mock_hwcap2 = 0;
+void cpuinfo_set_hwcap2(uint64_t hwcap2) {
+	mock_hwcap2 = hwcap2;
+}
+#endif
+
+#if CPUINFO_ARCH_ARM
+typedef unsigned long (*getauxval_function_t)(unsigned long);
+
+bool cpuinfo_arm_linux_hwcap_from_getauxval(uint32_t hwcap[restrict static 1], uint64_t hwcap2[restrict static 1]) {
+#if CPUINFO_MOCK
+	*hwcap = mock_hwcap;
+	*hwcap2 = mock_hwcap2;
+	return true;
+#elif defined(__ANDROID__)
+	/* Android: dynamically check if getauxval is supported */
+	void* libc = NULL;
+	getauxval_function_t getauxval = NULL;
+
+	dlerror();
+	libc = dlopen("libc.so", RTLD_LAZY);
+	if (libc == NULL) {
+		cpuinfo_log_warning("failed to load libc.so: %s", dlerror());
+		goto cleanup;
+	}
+
+	getauxval = (getauxval_function_t)dlsym(libc, "getauxval");
+	if (getauxval == NULL) {
+		cpuinfo_log_info("failed to locate getauxval in libc.so: %s", dlerror());
+		goto cleanup;
+	}
+
+	*hwcap = getauxval(AT_HWCAP);
+	*hwcap2 = getauxval(AT_HWCAP2);
+
+cleanup:
+	if (libc != NULL) {
+		dlclose(libc);
+		libc = NULL;
+	}
+	return getauxval != NULL;
+#elif defined(__GLIBC__) && defined(__GLIBC_MINOR__) && (__GLIBC__ > 2 || __GLIBC__ == 2 && __GLIBC_MINOR__ >= 16)
+	/* GNU/Linux: getauxval is supported since glibc-2.16 */
+	*hwcap = getauxval(AT_HWCAP);
+	*hwcap2 = getauxval(AT_HWCAP2);
+	return true;
+#else
+	return false;
+#endif
+}
+
+#ifdef __ANDROID__
+bool cpuinfo_arm_linux_hwcap_from_procfs(uint32_t hwcap[restrict static 1], uint64_t hwcap2[restrict static 1]) {
+#if CPUINFO_MOCK
+	*hwcap = mock_hwcap;
+	*hwcap2 = mock_hwcap2;
+	return true;
+#else
+	uint64_t hwcaps[2] = {0, 0};
+	bool result = false;
+	int file = -1;
+
+	file = open("/proc/self/auxv", O_RDONLY);
+	if (file == -1) {
+		cpuinfo_log_warning("failed to open /proc/self/auxv: %s", strerror(errno));
+		goto cleanup;
+	}
+
+	ssize_t bytes_read;
+	do {
+		Elf32_auxv_t elf_auxv;
+		bytes_read = read(file, &elf_auxv, sizeof(Elf32_auxv_t));
+		if (bytes_read < 0) {
+			cpuinfo_log_warning("failed to read /proc/self/auxv: %s", strerror(errno));
+			goto cleanup;
+		} else if (bytes_read > 0) {
+			if (bytes_read == sizeof(elf_auxv)) {
+				switch (elf_auxv.a_type) {
+					case AT_HWCAP:
+						hwcaps[0] = (uint32_t)elf_auxv.a_un.a_val;
+						break;
+					case AT_HWCAP2:
+						hwcaps[1] = (uint64_t)elf_auxv.a_un.a_val;
+						break;
+				}
+			} else {
+				cpuinfo_log_warning(
+					"failed to read %zu bytes from /proc/self/auxv: %zu bytes available",
+					sizeof(elf_auxv),
+					(size_t)bytes_read);
+				goto cleanup;
+			}
+		}
+	} while (bytes_read == sizeof(Elf32_auxv_t));
+
+	/* Success, commit results */
+	*hwcap = hwcaps[0];
+	*hwcap2 = hwcaps[1];
+	result = true;
+
+cleanup:
+	if (file != -1) {
+		close(file);
+		file = -1;
+	}
+	return result;
+#endif
+}
+#endif /* __ANDROID__ */
+#elif CPUINFO_ARCH_ARM64
+void cpuinfo_arm_linux_hwcap_from_getauxval(uint32_t hwcap[restrict static 1], uint64_t hwcap2[restrict static 1]) {
+#if CPUINFO_MOCK
+	*hwcap = mock_hwcap;
+	*hwcap2 = mock_hwcap2;
+#else
+	*hwcap = (uint32_t)getauxval(AT_HWCAP);
+	*hwcap2 = (uint64_t)getauxval(AT_HWCAP2);
+	return;
+#endif
+}
+#endif