WebSVN – HelenOS – Diff – //branches/network/kernel/generic/src/lib/string.c

 #include <cpu.h>
 #include <arch/asm.h>
 #include <arch.h>
 #include <errno.h>
 #include <align.h>
+#include <debug.h>
 /** Byte mask consisting of lowest @n bits (out of 8) */
 #define LO_MASK_8(n)  ((uint8_t) ((1 << (n)) - 1))
 /** Byte mask consisting of lowest @n bits (out of 32) */
     return 0;
+}
-/** Copy NULL-terminated string.
+/** Copy string.
+ *
- * Copy source string @a src to destination buffer @a dst.
+ * Copy source string @a src to destination buffer @a dest.
- * No more than @a size bytes are written. NULL-terminator is always
+ * No more than @a size bytes are written. If the size of the output buffer
- * written after the last succesfully copied character (i.e. if the
+ * is at least one byte, the output string will always be well-formed, i.e.
- * destination buffer is has at least 1 byte, it will be always
+ * null-terminated and containing only complete characters.
- * NULL-terminated).
+ *
- * @param src   Source string.
  * @param dst   Destination buffer.
- * @param count Size of the destination buffer.
+ * @param count Size of the destination buffer (must be > 0).
- *
+ * @param src   Source string.
  */
-void str_ncpy(char *dst, const char *src, size_t size)
+void str_cpy(char *dest, size_t size, const char *src)
+{
-    /* No space for the NULL-terminator in the buffer */
-    if (size == 0)
-        return;
     wchar_t ch;
-    size_t str_off = 0;
+    size_t src_off;
-    size_t dst_off = 0;
+    size_t dest_off;
+    /* There must be space for a null terminator in the buffer. */
+    ASSERT(size > 0);
+    src_off = 0;
+    dest_off = 0;
-    while ((ch = str_decode(src, &str_off, STR_NO_LIMIT)) != 0) {
+    while ((ch = str_decode(src, &src_off, STR_NO_LIMIT)) != 0) {
-        if (chr_encode(ch, dst, &dst_off, size) != EOK)
+        if (chr_encode(ch, dest, &dest_off, size - 1) != EOK)
             break;
+    }
+    dest[dest_off] = '\0';
+}
+/** Copy size-limited substring.
+ *
+ * Copy prefix of string @a src of max. size @a size to destination buffer
+ * @a dest. No more than @a size bytes are written. The output string will
+ * always be well-formed, i.e. null-terminated and containing only complete
+ * characters.
+ *
+ * No more than @a n bytes are read from the input string, so it does not
+ * have to be null-terminated.
+ *
+ * @param dst   Destination buffer.
+ * @param count Size of the destination buffer (must be > 0).
+ * @param src   Source string.
+ * @param n Maximum number of bytes to read from @a src.
+ */
+void str_ncpy(char *dest, size_t size, const char *src, size_t n)
+{
+    wchar_t ch;
+    size_t src_off;
+    size_t dest_off;
+    /* There must be space for a null terminator in the buffer. */
+    ASSERT(size > 0);
-    if (dst_off >= size)
+    src_off = 0;
-        dst[size - 1] = 0;
+    dest_off = 0;
+    while ((ch = str_decode(src, &src_off, n)) != 0) {
+        if (chr_encode(ch, dest, &dest_off, size - 1) != EOK)
+            break;
-    else
+    }
-        dst[dst_off] = 0;
+    dest[dest_off] = '\0';
+}
 /** Copy NULL-terminated wide string to string
+ *
  * Copy source wide string @a src to destination buffer @a dst.
  */
 const char *str_chr(const char *str, wchar_t ch)
+{
     wchar_t acc;
     size_t off = 0;
+    size_t last = 0;
     while ((acc = str_decode(str, &off, STR_NO_LIMIT)) != 0) {
         if (acc == ch)
-            return (str + off);
+            return (str + last);
+        last = off;
+    }
     return NULL;
+}

Subversion Repositories HelenOS

(root)//branches/network/kernel/generic/src/lib/string.c – Rev 4263 → 4327