Diff: ntlibc.cpp

Revision:

1:973cd917b72c

Parent:

0:7147d6024de8

Child:

2:61c70abc5690

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ntlibc.cpp	Thu Mar 19 14:08:15 2015 +0000
@@ -0,0 +1,137 @@
+/**
+ * @file ntlibc.c
+ * @author Shinichiro Nakamura
+ * @brief NT-Shellで用いる小規模libcの実装。
+ */
+
+/*
+ * ===============================================================
+ *  Natural Tiny Shell (NT-Shell)
+ *  Version 0.0.6
+ * ===============================================================
+ * Copyright (c) 2010-2011 Shinichiro Nakamura
+ *
+ * Permission is hereby granted, free of charge, to any person
+ * obtaining a copy of this software and associated documentation
+ * files (the "Software"), to deal in the Software without
+ * restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following
+ * conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
+ * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+ * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ * ===============================================================
+ */
+
+#include "ntlibc.h"
+
+size_t ntlibc_strlen(const char *s)
+{
+    const char *p = s;
+    int cnt = 0;
+    while (*p) {
+        cnt++;
+        p++;
+    }
+    return cnt;
+}
+
+char *ntlibc_strcpy(char *des, const char *src)
+{
+    char *d = des;
+    const char *s = src;
+    while (*s) {
+        *d = *s;
+        d++;
+        s++;
+    }
+    *d = '\0';
+    return des;
+}
+
+char *ntlibc_strcat(char *des, const char *src)
+{
+    char *d = des;
+    const char *s = src;
+    while (*d) {
+        d++;
+    }
+    while (*s) {
+        *d = *s;
+        d++;
+        s++;
+    }
+    *d = '\0';
+    return des;
+}
+
+int ntlibc_strcmp(const char *s1, const char *s2)
+{
+    char *p1 = (char *)s1;
+    char *p2 = (char *)s2;
+    while (*p1 || *p2) {
+        if (*p1 != *p2) {
+            return (*p1 < *p2) ? -1 : 1;
+        }
+        p1++;
+        p2++;
+    }
+    if (*p1 == *p2) {
+        return 0;
+    } else {
+        return (*p1 < *p2) ? -1 : 1;
+    }
+}
+
+int ntlibc_strncmp(const char *s1, const char *s2, size_t n)
+{
+    char *p1 = (char *)s1;
+    char *p2 = (char *)s2;
+    size_t len = 0;
+    while (*p1 || *p2) {
+        if (n <= len) {
+            break;
+        }
+        if (*p1 != *p2) {
+            return (*p1 < *p2) ? -1 : 1;
+        }
+        p1++;
+        p2++;
+        len++;
+    }
+    return 0;
+}
+
+#if 0
+#include <stdio.h>
+int main(void);
+int main(void) {
+    char *str_a = "That";
+    char *str_b = "The";
+    printf("strcmp(%s,%s) = %d, %d\n",
+            str_a, str_b,
+            strcmp(str_a, str_b),
+            ntlibc_strcmp(str_a, str_b));
+    printf("strncmp(%s,%s,2) = %d, %d\n",
+            str_a, str_b,
+            strncmp(str_a, str_b, 2),
+            ntlibc_strncmp(str_a, str_b, 2));
+    printf("strncmp(%s,%s,3) = %d, %d\n",
+            str_a, str_b,
+            strncmp(str_a, str_b, 3),
+            ntlibc_strncmp(str_a, str_b, 3));
+    return 0;
+}
+#endif
+