SecBSD's official ports repository

sysutils/cpuid/files/cpuid.c

@@ -0,0 +1,87 @@
+/*
+ * Copyright (c) 2016 Philip Guenther <guenther@openbsd.org>
+ * Copyright (c) 2016 Stuart Henderson <sthen@openbsd.org>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <ctype.h>
+#include <err.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+static inline void
+showreg(const char *reg, unsigned value, int show_ascii)
+{
+	unsigned char c;
+
+	printf("%s = 0x%08x    % 10u", reg, value, value);
+
+	if (show_ascii) {
+		fputs("    \"", stdout);
+		c =  value        & 0xff; putchar(isprint(c) ? c : '?');
+		c = (value >>  8) & 0xff; putchar(isprint(c) ? c : '?');
+		c = (value >> 16) & 0xff; putchar(isprint(c) ? c : '?');
+		c = (value >> 24) & 0xff; putchar(isprint(c) ? c : '?');
+		putchar('"');
+	}
+	putchar('\n');
+}
+
+int
+main(int argc, char **argv)
+{
+	unsigned long	code, leaf;
+	unsigned int	a, b, c, d;
+
+	leaf = 0;
+	switch (argc) {
+	case 3:
+		errno = 0;
+		/* strtoul() to both dec and hex input */
+		leaf = strtoul(argv[2], NULL, 0);
+		if (leaf == ULONG_MAX && errno == ERANGE || leaf > UINT_MAX)
+			errx(1, "cpuid leaf out of range: %s", argv[2]);
+		/* FALLTHROUGH */
+	case 2:
+		errno = 0;
+		code = strtoul(argv[1], NULL, 0);
+		if (code == ULONG_MAX && errno == ERANGE || code > UINT_MAX)
+			errx(1, "cpuid code out of range: %s", argv[1]);
+		break;
+	default:
+		printf("usage: cpuid code [leaf]\n");
+		exit(1);
+	}
+
+	/*
+	 * The dance here with %ebx is to work around a gcc bug on i386,
+	 * where gcc uses %ebx for PIC/PIE code but fail to save/reload
+	 * it around __asm() blocks that use %ebx.  Oddly, if you declare
+	 * that the __asm() *clobbers* ebx, gcc complains.
+	 * Anyway, this dance is unnecessary but harmless on amd64.
+	 */
+	__asm volatile("mov %%ebx, %%esi; cpuid; xchg %%esi, %%ebx"
+	    : "=a" (a), "=S" (b), "=c" (c), "=d" (d)
+	    : "a" (code), "c" (leaf));
+
+	showreg("eax", a, 1);
+	showreg("ebx", b, 1);
+	showreg("ecx", c, 1);
+	showreg("edx", d, 1);
+	//getc(stdin);
+	return 0;
+}