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authorDaniel Lezcano <daniel.lezcano@linaro.org>2021-12-09 13:57:57 +0100
committerDaniel Lezcano <daniel.lezcano@linaro.org>2021-12-09 13:57:57 +0100
commit8632987380765dee716d460640aa58d58d52998e (patch)
treef8f4a55fc95c1060f97d64ee4d6db5c9693bb794 /lib/string_helpers.c
parent410fbda49cc9b2165e80b87880f164d9644b460d (diff)
parentc4f5b30dda01f2f6979a9681142de454991182ee (diff)
Merge branch 'reset/of-get-optional-exclusive' of git://git.pengutronix.de/pza/linux into timers/drivers/next
"Add optional variant of of_reset_control_get_exclusive(). If the requested reset is not specified in the device tree, this function returns NULL instead of an error." This dependency is needed for the Generic Timer Module (a.k.a OSTM) support for RZ/G2L. Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Diffstat (limited to 'lib/string_helpers.c')
-rw-r--r--lib/string_helpers.c219
1 files changed, 219 insertions, 0 deletions
diff --git a/lib/string_helpers.c b/lib/string_helpers.c
index 5a35c7e16e96..d5d008f5b1d9 100644
--- a/lib/string_helpers.c
+++ b/lib/string_helpers.c
@@ -361,6 +361,9 @@ static bool escape_special(unsigned char c, char **dst, char *end)
case '\e':
to = 'e';
break;
+ case '"':
+ to = '"';
+ break;
default:
return false;
}
@@ -474,6 +477,7 @@ static bool escape_hex(unsigned char c, char **dst, char *end)
* '\t' - horizontal tab
* '\v' - vertical tab
* %ESCAPE_SPECIAL:
+ * '\"' - double quote
* '\\' - backslash
* '\a' - alert (BEL)
* '\e' - escape
@@ -692,3 +696,218 @@ void kfree_strarray(char **array, size_t n)
kfree(array);
}
EXPORT_SYMBOL_GPL(kfree_strarray);
+
+/**
+ * strscpy_pad() - Copy a C-string into a sized buffer
+ * @dest: Where to copy the string to
+ * @src: Where to copy the string from
+ * @count: Size of destination buffer
+ *
+ * Copy the string, or as much of it as fits, into the dest buffer. The
+ * behavior is undefined if the string buffers overlap. The destination
+ * buffer is always %NUL terminated, unless it's zero-sized.
+ *
+ * If the source string is shorter than the destination buffer, zeros
+ * the tail of the destination buffer.
+ *
+ * For full explanation of why you may want to consider using the
+ * 'strscpy' functions please see the function docstring for strscpy().
+ *
+ * Returns:
+ * * The number of characters copied (not including the trailing %NUL)
+ * * -E2BIG if count is 0 or @src was truncated.
+ */
+ssize_t strscpy_pad(char *dest, const char *src, size_t count)
+{
+ ssize_t written;
+
+ written = strscpy(dest, src, count);
+ if (written < 0 || written == count - 1)
+ return written;
+
+ memset(dest + written + 1, 0, count - written - 1);
+
+ return written;
+}
+EXPORT_SYMBOL(strscpy_pad);
+
+/**
+ * skip_spaces - Removes leading whitespace from @str.
+ * @str: The string to be stripped.
+ *
+ * Returns a pointer to the first non-whitespace character in @str.
+ */
+char *skip_spaces(const char *str)
+{
+ while (isspace(*str))
+ ++str;
+ return (char *)str;
+}
+EXPORT_SYMBOL(skip_spaces);
+
+/**
+ * strim - Removes leading and trailing whitespace from @s.
+ * @s: The string to be stripped.
+ *
+ * Note that the first trailing whitespace is replaced with a %NUL-terminator
+ * in the given string @s. Returns a pointer to the first non-whitespace
+ * character in @s.
+ */
+char *strim(char *s)
+{
+ size_t size;
+ char *end;
+
+ size = strlen(s);
+ if (!size)
+ return s;
+
+ end = s + size - 1;
+ while (end >= s && isspace(*end))
+ end--;
+ *(end + 1) = '\0';
+
+ return skip_spaces(s);
+}
+EXPORT_SYMBOL(strim);
+
+/**
+ * sysfs_streq - return true if strings are equal, modulo trailing newline
+ * @s1: one string
+ * @s2: another string
+ *
+ * This routine returns true iff two strings are equal, treating both
+ * NUL and newline-then-NUL as equivalent string terminations. It's
+ * geared for use with sysfs input strings, which generally terminate
+ * with newlines but are compared against values without newlines.
+ */
+bool sysfs_streq(const char *s1, const char *s2)
+{
+ while (*s1 && *s1 == *s2) {
+ s1++;
+ s2++;
+ }
+
+ if (*s1 == *s2)
+ return true;
+ if (!*s1 && *s2 == '\n' && !s2[1])
+ return true;
+ if (*s1 == '\n' && !s1[1] && !*s2)
+ return true;
+ return false;
+}
+EXPORT_SYMBOL(sysfs_streq);
+
+/**
+ * match_string - matches given string in an array
+ * @array: array of strings
+ * @n: number of strings in the array or -1 for NULL terminated arrays
+ * @string: string to match with
+ *
+ * This routine will look for a string in an array of strings up to the
+ * n-th element in the array or until the first NULL element.
+ *
+ * Historically the value of -1 for @n, was used to search in arrays that
+ * are NULL terminated. However, the function does not make a distinction
+ * when finishing the search: either @n elements have been compared OR
+ * the first NULL element was found.
+ *
+ * Return:
+ * index of a @string in the @array if matches, or %-EINVAL otherwise.
+ */
+int match_string(const char * const *array, size_t n, const char *string)
+{
+ int index;
+ const char *item;
+
+ for (index = 0; index < n; index++) {
+ item = array[index];
+ if (!item)
+ break;
+ if (!strcmp(item, string))
+ return index;
+ }
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL(match_string);
+
+/**
+ * __sysfs_match_string - matches given string in an array
+ * @array: array of strings
+ * @n: number of strings in the array or -1 for NULL terminated arrays
+ * @str: string to match with
+ *
+ * Returns index of @str in the @array or -EINVAL, just like match_string().
+ * Uses sysfs_streq instead of strcmp for matching.
+ *
+ * This routine will look for a string in an array of strings up to the
+ * n-th element in the array or until the first NULL element.
+ *
+ * Historically the value of -1 for @n, was used to search in arrays that
+ * are NULL terminated. However, the function does not make a distinction
+ * when finishing the search: either @n elements have been compared OR
+ * the first NULL element was found.
+ */
+int __sysfs_match_string(const char * const *array, size_t n, const char *str)
+{
+ const char *item;
+ int index;
+
+ for (index = 0; index < n; index++) {
+ item = array[index];
+ if (!item)
+ break;
+ if (sysfs_streq(item, str))
+ return index;
+ }
+
+ return -EINVAL;
+}
+EXPORT_SYMBOL(__sysfs_match_string);
+
+/**
+ * strreplace - Replace all occurrences of character in string.
+ * @s: The string to operate on.
+ * @old: The character being replaced.
+ * @new: The character @old is replaced with.
+ *
+ * Returns pointer to the nul byte at the end of @s.
+ */
+char *strreplace(char *s, char old, char new)
+{
+ for (; *s; ++s)
+ if (*s == old)
+ *s = new;
+ return s;
+}
+EXPORT_SYMBOL(strreplace);
+
+/**
+ * memcpy_and_pad - Copy one buffer to another with padding
+ * @dest: Where to copy to
+ * @dest_len: The destination buffer size
+ * @src: Where to copy from
+ * @count: The number of bytes to copy
+ * @pad: Character to use for padding if space is left in destination.
+ */
+void memcpy_and_pad(void *dest, size_t dest_len, const void *src, size_t count,
+ int pad)
+{
+ if (dest_len > count) {
+ memcpy(dest, src, count);
+ memset(dest + count, pad, dest_len - count);
+ } else {
+ memcpy(dest, src, dest_len);
+ }
+}
+EXPORT_SYMBOL(memcpy_and_pad);
+
+#ifdef CONFIG_FORTIFY_SOURCE
+void fortify_panic(const char *name)
+{
+ pr_emerg("detected buffer overflow in %s\n", name);
+ BUG();
+}
+EXPORT_SYMBOL(fortify_panic);
+#endif /* CONFIG_FORTIFY_SOURCE */