Implemented getenv(), atexit(), number parsing, and more

photon/libc/string/memcmp.c

@@ -0,0 +1,14 @@
+#include <stddef.h>
+
+int memcmp(const void *a, const void *b, size_t n)
+{
+    const unsigned char *s1 = a, *s2 = b;
+
+    for (size_t i = 0; i < n; i++) {
+        if (s1[i] != s2[i]) {
+            return ((s1[i] < s2[i]) ? -1 : 1);
+        }
+    }
+
+    return 0;
+}

photon/libc/string/memmove.c

@@ -0,0 +1,27 @@
+#include <string.h>
+
+#define ALIGNED(p) (!((long)p & (sizeof(long) - 1)))
+#define QUADBLOCKSIZE (sizeof(long) << 2)
+#define BLOCKSIZE (sizeof(long))
+
+static void *memcpy_r(void *dest, const void *src, size_t sz)
+{
+    unsigned char *d = dest;
+    const unsigned char *s = src;
+
+    for (size_t i = 0; i < sz; i++) {
+        size_t b = sz - i - 1;
+        d[b] = s[b];
+    }
+
+    return dest;
+}
+
+void *memmove(void *dest, const void *src, size_t n)
+{
+    if (dest > src) {
+        return memcpy(dest, src, n);
+    } else {
+        return memcpy_r(dest, src, n);
+    }
+}

photon/libc/string/strcmp.c

@@ -1,19 +1,25 @@
+#include <stddef.h>
+
 int strcmp(const char *s1, const char *s2)
 {
     int i;
-    for (i = 0; s1[i] == s2[i]; i++)
-        if (s1[i] == '\0')
+    for (i = 0; s1[i] == s2[i]; i++) {
+        if (s1[i] == '\0') {
             return 0;
+        }
+    }
 
     return s1[i] - s2[i];
 }
 
-int strncmp(const char *s1, const char *s2, unsigned int n)
+int strncmp(const char *s1, const char *s2, size_t n)
 {
-    for (; n > 0; s1++, s2++, --n)
-        if (*s1 != *s2)
+    for (; n > 0; s1++, s2++, --n) {
+        if (*s1 != *s2) {
             return ((*(unsigned char *)s1 < *(unsigned char *)s2) ? -1 : 1);
-        else if (*s1 == '\0')
+        } else if (*s1 == '\0') {
             return 0;
+        }
+    }
     return 0;
 }