mm: move MAP_SYNC to asm-generic/mman-common.h

[linux-2.6-block.git] / lib / string_helpers.c

diff --git a/lib/string_helpers.c b/lib/string_helpers.c
index 4403e1924f7307d190edd67f00e5e987a4d322b1..963050c0283e9cd1055e7a1e459cae30ae76eda8 100644 (file)
--- a/lib/string_helpers.c
+++ b/lib/string_helpers.c
@@ -231,35 +231,36 @@ static bool unescape_special(char **src, char **dst)
  * @src:       source buffer (escaped)
  * @dst:       destination buffer (unescaped)
  * @size:      size of the destination buffer (0 to unlimit)
- * @flags:     combination of the flags (bitwise OR):
- *     %UNESCAPE_SPACE:
+ * @flags:     combination of the flags.
+ *
+ * Description:
+ * The function unquotes characters in the given string.
+ *
+ * Because the size of the output will be the same as or less than the size of
+ * the input, the transformation may be performed in place.
+ *
+ * Caller must provide valid source and destination pointers. Be aware that
+ * destination buffer will always be NULL-terminated. Source string must be
+ * NULL-terminated as well.  The supported flags are::
+ *
+ *     UNESCAPE_SPACE:
  *             '\f' - form feed
  *             '\n' - new line
  *             '\r' - carriage return
  *             '\t' - horizontal tab
  *             '\v' - vertical tab
- *     %UNESCAPE_OCTAL:
+ *     UNESCAPE_OCTAL:
  *             '\NNN' - byte with octal value NNN (1 to 3 digits)
- *     %UNESCAPE_HEX:
+ *     UNESCAPE_HEX:
  *             '\xHH' - byte with hexadecimal value HH (1 to 2 digits)
- *     %UNESCAPE_SPECIAL:
+ *     UNESCAPE_SPECIAL:
  *             '\"' - double quote
  *             '\\' - backslash
  *             '\a' - alert (BEL)
  *             '\e' - escape
- *     %UNESCAPE_ANY:
+ *     UNESCAPE_ANY:
  *             all previous together
  *
- * Description:
- * The function unquotes characters in the given string.
- *
- * Because the size of the output will be the same as or less than the size of
- * the input, the transformation may be performed in place.
- *
- * Caller must provide valid source and destination pointers. Be aware that
- * destination buffer will always be NULL-terminated. Source string must be
- * NULL-terminated as well.
- *
  * Return:
  * The amount of the characters processed to the destination buffer excluding
  * trailing '\0' is returned.
@@ -441,7 +442,29 @@ static bool escape_hex(unsigned char c, char **dst, char *end)
  * @isz:       source buffer size
  * @dst:       destination buffer (escaped)
  * @osz:       destination buffer size
- * @flags:     combination of the flags (bitwise OR):
+ * @flags:     combination of the flags
+ * @only:      NULL-terminated string containing characters used to limit
+ *             the selected escape class. If characters are included in @only
+ *             that would not normally be escaped by the classes selected
+ *             in @flags, they will be copied to @dst unescaped.
+ *
+ * Description:
+ * The process of escaping byte buffer includes several parts. They are applied
+ * in the following sequence.
+ *
+ *     1. The character is matched to the printable class, if asked, and in
+ *        case of match it passes through to the output.
+ *     2. The character is not matched to the one from @only string and thus
+ *        must go as-is to the output.
+ *     3. The character is checked if it falls into the class given by @flags.
+ *        %ESCAPE_OCTAL and %ESCAPE_HEX are going last since they cover any
+ *        character. Note that they actually can't go together, otherwise
+ *        %ESCAPE_HEX will be ignored.
+ *
+ * Caller must provide valid source and destination pointers. Be aware that
+ * destination buffer will not be NULL-terminated, thus caller have to append
+ * it if needs.   The supported flags are::
+ *
  *     %ESCAPE_SPACE: (special white space, not space itself)
  *             '\f' - form feed
  *             '\n' - new line
@@ -464,26 +487,6 @@ static bool escape_hex(unsigned char c, char **dst, char *end)
  *             all previous together
  *     %ESCAPE_HEX:
  *             '\xHH' - byte with hexadecimal value HH (2 digits)
- * @only:      NULL-terminated string containing characters used to limit
- *             the selected escape class. If characters are included in @only
- *             that would not normally be escaped by the classes selected
- *             in @flags, they will be copied to @dst unescaped.
- *
- * Description:
- * The process of escaping byte buffer includes several parts. They are applied
- * in the following sequence.
- *     1. The character is matched to the printable class, if asked, and in
- *        case of match it passes through to the output.
- *     2. The character is not matched to the one from @only string and thus
- *        must go as-is to the output.
- *     3. The character is checked if it falls into the class given by @flags.
- *        %ESCAPE_OCTAL and %ESCAPE_HEX are going last since they cover any
- *        character. Note that they actually can't go together, otherwise
- *        %ESCAPE_HEX will be ignored.
- *
- * Caller must provide valid source and destination pointers. Be aware that
- * destination buffer will not be NULL-terminated, thus caller have to append
- * it if needs.
  *
  * Return:
  * The total size of the escaped output that would be generated for
@@ -540,6 +543,25 @@ int string_escape_mem(const char *src, size_t isz, char *dst, size_t osz,
 }
 EXPORT_SYMBOL(string_escape_mem);
 
+int string_escape_mem_ascii(const char *src, size_t isz, char *dst,
+                                       size_t osz)
+{
+       char *p = dst;
+       char *end = p + osz;
+
+       while (isz--) {
+               unsigned char c = *src++;
+
+               if (!isprint(c) || !isascii(c) || c == '"' || c == '\\')
+                       escape_hex(c, &p, end);
+               else
+                       escape_passthrough(c, &p, end);
+       }
+
+       return p - dst;
+}
+EXPORT_SYMBOL(string_escape_mem_ascii);
+
 /*
  * Return an allocated string that has been escaped of special characters
  * and double quotes, making it safe to log in quotes.