initial exec support

1 files changed, 510 insertions, 0 deletions

diff --git a/tests/common/string.c b/tests/common/string.c
new file mode 100644
index 0000000..e1519b0
--- /dev/null
+++ b/tests/common/string.c
@@ -0,0 +1,510 @@
+/* copied straight from the kernel */
+#include <common/string.h>
+#include <kmi/utils.h>
+#include <kmi/types.h>
+
+char *strcpy(char * restrict dst, const char * restrict src)
+{
+	const char *s1 = src;
+	char *s2 = dst;
+
+	while (*s1)
+		*(s2++) = *(s1++);
+
+	return dst;
+}
+
+char *strncpy(char * restrict dst, const char * restrict src, size_t num)
+{
+	const char *s1 = src;
+	char *s2 = dst;
+
+	/* copy s1 into s2 */
+	while (num-- && *s1)
+		*(s2++) = *(s1++);
+
+	/* the previous loop always overshoots by one */
+	num++;
+
+	/* pad with zeroes if num is not yet zero */
+	while (num--)
+		*(s2++) = 0;
+
+	return dst;
+}
+
+char *strcat(char * restrict dst, const char * restrict src)
+{
+	const char *s1 = src;
+	size_t l1 = strlen(s1);
+	char *s2 = dst + l1;
+
+	while (*s1)
+		*(s2++) = *(s1++);
+
+	/* append null character */
+	*s2 = 0;
+
+	return dst;
+}
+
+char *strncat(char * restrict dst, const char * restrict src, size_t num)
+{
+	const char *s1 = src;
+	size_t l1 = strlen(s1);
+	char *s2 = dst + l1;
+
+	while (num-- && *s1)
+		*(s2++) = *(s1++);
+
+	/* append null character */
+	*s2 = 0;
+
+	return dst;
+}
+
+int strcmp(const char *str1, const char *str2)
+{
+	const char *s1 = (const char *)str1;
+	const char *s2 = (const char *)str2;
+
+	while ((*(s1++) == *(s2++)) && *s1 && *s2)
+		;
+
+	return (int)(s1[-1] - s2[-1]);
+}
+
+int strncmp(const char *str1, const char *str2, size_t num)
+{
+	const char *s1 = (const char *)str1;
+	const char *s2 = (const char *)str2;
+
+	while ((*(s1++) == *(s2++)) && *s1 && *s2 && --num)
+		;
+
+	return (int)(s1[-1] - s2[-1]);
+}
+
+char *strchr(const char *str, int chr)
+{
+	const char *s1 = str;
+	ssize_t num = strlen(s1);
+
+	while (num-- && *(s1++) != chr)
+		;
+
+	if (num < 0)
+		return 0;
+
+	return (char *)(s1 - 1);
+}
+
+char *strtok(char * restrict str, const char * restrict delims)
+{
+	static char *cont = 0;
+	const char *s1 = str;
+
+	if (!s1)
+		s1 = cont;
+
+	if (!s1)
+		return 0;
+
+	s1 = strpbrk(s1, delims);
+
+	if (!s1)
+		cont = 0;
+	else
+		cont = (char *)s1 + 1;
+
+	return (char *)s1;
+}
+
+/* should probably test out these functions somehwere, blergh */
+char *strstr(const char *str1, const char *str2)
+{
+	/* boyer-moore-horspool */
+	char table[256] = { 0 };
+	size_t sl = strlen(str1);
+	size_t pl = strlen(str2);
+
+	const unsigned char *s1 = (const unsigned char *)str1;
+	const unsigned char *haystack = (const unsigned char *)s1;
+	const unsigned char *needle = (const unsigned char *)str2;
+
+	for (size_t i = 0; i < 256; ++i)
+		table[i] = pl;
+
+	/* generate deltas */
+	for (size_t i = 0; i < pl - 1; ++i)
+		table[needle[i]] = pl - i - 1;
+
+	size_t skip = 0;
+	while (sl - skip >= pl) {
+		s1 = &haystack[skip];
+
+		if (!memcmp(s1, needle, pl))
+			return (char *)s1;
+
+		skip += table[haystack[skip + pl - 1]];
+	}
+
+	return 0;
+}
+
+char *strrchr(const char *str, int chr)
+{
+	ssize_t num = strlen(str);
+	const char *s1 = (str + num) - 1;
+
+	while (num-- && *(s1--) != chr)
+		;
+
+	if (num < 0)
+		return 0;
+
+	return (char *)(s1 + 1);
+}
+
+char *strpbrk(const char *str1, const char *str2)
+{
+	size_t i = strcspn(str1, str2);
+
+	if (!i)
+		return 0;
+
+	return (char *)(str1 + i);
+}
+
+size_t strcspn(const char *str1, const char *str2)
+{
+	char table[256] = { 0 };
+	const unsigned char *s1 = (const unsigned char *)str1;
+	const unsigned char *s2 = (const unsigned char *)s1;
+	const unsigned char *t1 = (const unsigned char *)str2;
+
+	/* populate table */
+	while (*(t1++))
+		table[*t1] = 1;
+
+	for (;;) {
+		if (table[*(s2++)])
+			break;
+	}
+
+	/* the for loop overshoots by one */
+	return (size_t)(s2 - s1) - 1;
+}
+
+size_t strspn(const char *str1, const char *str2)
+{
+	char table[256] = { 0 };
+	const unsigned char *s1 = (const unsigned char *)str1;
+	const unsigned char *s2 = (const unsigned char *)s1;
+	const unsigned char *t1 = (const unsigned char *)str2;
+
+	/* populate table */
+	while (*(t1++))
+		table[*t1] = 1;
+
+	for (;;) {
+		if (!table[*(s2++)])
+			break;
+	}
+
+	/* the for loop overshoots by one */
+	return (size_t)(s2 - s1) - 1;
+}
+
+size_t strlen(const char *str)
+{
+	const char *s1 = str;
+	while (*(s1++))
+		;
+
+	/* the loop overshoots by one */
+	return (size_t)(s1 - str) - 1;
+}
+
+/* not a macro */
+size_t strnlen(const char *str, size_t num)
+{
+	const char *s1 = str;
+	while (num-- && *(s1++))
+		;
+
+	return (size_t)(s1 - str) - 1;
+}
+
+void *memchr(const void *ptr, int val, size_t num)
+{
+	const char *p1 = (char *)ptr;
+	ssize_t n = num;
+	char c = (char)val;
+
+	while (n-- && *(p1++) != c)
+		;
+
+	if (n < 0)
+		return 0;
+
+	return (void *)(p1 - 1);
+}
+
+/** @defgroup group1 Optimized specializations
+ *
+ * The two most used memory operations get their special optimized versions for
+ * aligned manipulations, which is what the vast majority of our huge operations
+ * like page zeroing are.
+ *
+ * @{
+ */
+
+/** How many longs per iteration we want to process. An address and size must be
+ * aligned to MAGIC_NUMBER * sizeof(long) bytes. */
+#define MAGIC_NUMBER 8
+
+/**
+ * Optimized version of memcpy() for big regions.
+ * All parameters must be aligned to MAGIC_NUMBER * sizeof(long).
+ *
+ * @param dst Destination to copy to.
+ * @param src Source to copy from.
+ * @param num Number of bytes to copy.
+ * @return dst
+ */
+static inline void *__aligned_memcpy(long *restrict dst,
+                                     const long *restrict src, size_t num)
+{
+	size_t count = num / sizeof(long);
+	for (size_t i = 0; i < count; i += MAGIC_NUMBER) {
+		dst[i + 0] = src[i + 0];
+		dst[i + 1] = src[i + 1];
+		dst[i + 2] = src[i + 2];
+		dst[i + 3] = src[i + 3];
+		dst[i + 4] = src[i + 4];
+		dst[i + 5] = src[i + 5];
+		dst[i + 6] = src[i + 6];
+		dst[i + 7] = src[i + 7];
+		/* would be kind of cool if there was some kind of forced unrolling,
+		 * as we need to do MAGIC_NUMBER of steps, preferably even with
+		 * optimizations disabled. For now I guess just be careful that
+		 * MAGIC_NUMBER matches the number of steps within loop */
+	}
+
+	return dst;
+}
+
+/**
+ * Optimized version of memset() for big regions.
+ * \p ptr and \p num must be aligned to MAGIC_NUMBER * sizeof(long).
+ *
+ * @param ptr Destination to write to.
+ * @param value Value (converted to unsigned char) to write.
+ * @param num Number of bytes to write.
+ * @return ptr
+ */
+static inline void *__aligned_memset(long *ptr, int value, size_t num)
+{
+	long bits = 0;
+	for (size_t i = 0; i < sizeof(long) / sizeof(unsigned char); ++i)
+		bits |= ((unsigned char)value) << i * CHAR_BIT;
+
+	size_t count = num / sizeof(long);
+	for (size_t i = 0; i < count; i += MAGIC_NUMBER) {
+		ptr[i + 0] = bits;
+		ptr[i + 1] = bits;
+		ptr[i + 2] = bits;
+		ptr[i + 3] = bits;
+		ptr[i + 4] = bits;
+		ptr[i + 5] = bits;
+		ptr[i + 6] = bits;
+		ptr[i + 7] = bits;
+	}
+
+	return ptr;
+}
+
+/** @} */
+
+void *memcpy(void * restrict dst, const void * restrict src,
+                           size_t num)
+{
+
+	if (is_aligned((uintptr_t)dst, sizeof(long) * MAGIC_NUMBER)
+	    && is_aligned((uintptr_t)src, sizeof(long) * MAGIC_NUMBER)
+	    && is_aligned(num, sizeof(long) * MAGIC_NUMBER))
+		return __aligned_memcpy(dst, src, num);
+
+	const char *m1 = (const char *)src;
+	char *m2 = (char *)dst;
+
+	while (num--)
+		*(m2++) = *(m1++);
+
+	return dst;
+}
+
+void *memset(void *ptr, int value, size_t num)
+{
+	if (is_aligned((uintptr_t)ptr, sizeof(long) * MAGIC_NUMBER)
+	    && is_aligned(num, sizeof(long) * MAGIC_NUMBER))
+		return __aligned_memset(ptr, value, num);
+
+	char *p = ptr;
+	char c = value;
+
+	while (num--)
+		*(p++) = c;
+
+	return ptr;
+}
+
+
+void *memmove(void *dst, const void *src, size_t num)
+{
+	const char *m1 = (const char *)src;
+	char *m2 = (char *)dst;
+
+	m1 += num;
+	m2 += num;
+
+	/* doesn't really take into account aliasing yet */
+	while (num--)
+		*(--m2) = *(--m1);
+
+	return dst;
+}
+
+int memcmp(const void *ptr1, const void *ptr2, size_t num)
+{
+	const char *p1 = (const char *)ptr1;
+	const char *p2 = (const char *)ptr2;
+
+	while ((*(p1++) == *(p2++)) && --num)
+		;
+
+	return (int)(p1[-1] - p2[-1]);
+}
+
+/**
+ * Convert ASCII hex character to integer.
+ * Allows both upper- and lowercase letters.
+ *
+ * @param c Character to convert.
+ * @return Corresponding integer value. That is, '1' => 1, '2' => 2, etc.
+ * \c -1 if conversion failed.
+ */
+static int __hexval(char c)
+{
+	if (c >= '0' && c <= '9')
+		return c - '0';
+
+	if (c >= 'a' && c <= 'f')
+		return 10 + c - 'a';
+
+	if (c >= 'A' && c <= 'F')
+		return 10 + c - 'A';
+
+	return -1;
+}
+
+/**
+ * Convert string assumed to represent hex
+ * value to corresponding pointer.
+ *
+ * @param s String to convert to value.
+ * @return Corresponding pointer value.
+ */
+static uintptr_t __hexuintptr(const char *s)
+{
+	uintptr_t res = 0;
+	int val = 0;
+	while ((val = __hexval(*(s++))) != -1) {
+		res *= 16;
+		res += val;
+	}
+
+	return res;
+}
+
+/**
+ * Convert ASCII decimal character to integer.
+ *
+ * @param c Character to convert.
+ * @return Corresponding integer value. That is, '1' => 1, '2' => 2, etc.
+ * \c -1 if conversion failed.
+ */
+static int __decval(char c)
+{
+	if (c >= '0' && c <= '9')
+		return c - '0';
+
+	return -1;
+}
+
+/**
+ * Convert string assumed to represent decimal
+ * value to corresponding pointer.
+ *
+ * @param s String to convert to value.
+ * @return Corresponding pointer value.
+ */
+static uintptr_t __decuintptr(const char *s)
+{
+	uintptr_t res = 0;
+	int val = 0;
+	while ((val = __decval(*(s++))) != -1) {
+		res *= 10;
+		res += val;
+	}
+
+	return res;
+}
+
+static int __octval(char c)
+{
+	if (c >= '0' && c <= '7')
+		return c - '0';
+
+	return -1;
+}
+
+static uintptr_t __octuintptr(const char *s)
+{
+	uintptr_t res = 0;
+	int val = 0;
+	while ((val = __octval(*(s++))) != -1) {
+		res *= 8;
+		res += val;
+	}
+
+	return res;
+}
+
+uintptr_t strtouintptr(const char *s)
+{
+	if (!s)
+		return 0;
+
+	if (s[0] == 0)
+		return 0;
+
+	if (s[0] == '0') {
+		if (s[1] == 0)
+			return 0;
+
+		if (s[1] == 'x' || s[1] == 'X')
+			return __hexuintptr(s + 2);
+
+		return __octuintptr(s + 1);
+	}
+
+	if (s[0] == '-')
+		return -__decuintptr(s + 1);
+
+	if (s[0] == '+')
+		return __decuintptr(s + 1);
+
+	return __decuintptr(s);
+}