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authorMark Brown <[email protected]>2022-10-19 16:37:01 +0100
committerMark Brown <[email protected]>2022-10-19 16:37:01 +0100
commit008f05a72d32dcc14038801649ec67af765fcc3c (patch)
treec958a2ab7039ea3e03621b1cbae4fcad41ee947c /include/linux/string.h
parent32def55d237e8507d4eb8442628fc2e59a899ea0 (diff)
parentdf496157a5afa1b6d1f4c46ad6549c2c346d1e59 (diff)
ASoC: jz4752b: Capture fixes
Merge series from Siarhei Volkau <[email protected]>: The patchset fixes: - Line In path stays powered off during capturing or bypass to mixer. - incorrectly represented dB values in alsamixer, et al. - incorrect represented Capture input selector in alsamixer in Playback tab. - wrong control selected as Capture Master
Diffstat (limited to 'include/linux/string.h')
-rw-r--r--include/linux/string.h43
1 files changed, 43 insertions, 0 deletions
diff --git a/include/linux/string.h b/include/linux/string.h
index 61ec7e4f6311..cf7607b32102 100644
--- a/include/linux/string.h
+++ b/include/linux/string.h
@@ -261,6 +261,49 @@ void memcpy_and_pad(void *dest, size_t dest_len, const void *src, size_t count,
int pad);
/**
+ * strtomem_pad - Copy NUL-terminated string to non-NUL-terminated buffer
+ *
+ * @dest: Pointer of destination character array (marked as __nonstring)
+ * @src: Pointer to NUL-terminated string
+ * @pad: Padding character to fill any remaining bytes of @dest after copy
+ *
+ * This is a replacement for strncpy() uses where the destination is not
+ * a NUL-terminated string, but with bounds checking on the source size, and
+ * an explicit padding character. If padding is not required, use strtomem().
+ *
+ * Note that the size of @dest is not an argument, as the length of @dest
+ * must be discoverable by the compiler.
+ */
+#define strtomem_pad(dest, src, pad) do { \
+ const size_t _dest_len = __builtin_object_size(dest, 1); \
+ \
+ BUILD_BUG_ON(!__builtin_constant_p(_dest_len) || \
+ _dest_len == (size_t)-1); \
+ memcpy_and_pad(dest, _dest_len, src, strnlen(src, _dest_len), pad); \
+} while (0)
+
+/**
+ * strtomem - Copy NUL-terminated string to non-NUL-terminated buffer
+ *
+ * @dest: Pointer of destination character array (marked as __nonstring)
+ * @src: Pointer to NUL-terminated string
+ *
+ * This is a replacement for strncpy() uses where the destination is not
+ * a NUL-terminated string, but with bounds checking on the source size, and
+ * without trailing padding. If padding is required, use strtomem_pad().
+ *
+ * Note that the size of @dest is not an argument, as the length of @dest
+ * must be discoverable by the compiler.
+ */
+#define strtomem(dest, src) do { \
+ const size_t _dest_len = __builtin_object_size(dest, 1); \
+ \
+ BUILD_BUG_ON(!__builtin_constant_p(_dest_len) || \
+ _dest_len == (size_t)-1); \
+ memcpy(dest, src, min(_dest_len, strnlen(src, _dest_len))); \
+} while (0)
+
+/**
* memset_after - Set a value after a struct member to the end of a struct
*
* @obj: Address of target struct instance