Date: Wed, 14 Mar 2007 00:27:18 +0100 (CET) From: Stefan Richter Subject: [PATCH 2/5] ieee1394: shrink csr1212_new_string_descriptor_leaf Make unnecessarily generic code specific and thus simpler. Shrink a lookup table from 128 to 16 bytes. Signed-off-by: Stefan Richter --- drivers/ieee1394/csr1212.c | 123 +++++++++++++------------------------ 1 file changed, 46 insertions(+), 77 deletions(-) Index: foo/drivers/ieee1394/csr1212.c =================================================================== --- foo.orig/drivers/ieee1394/csr1212.c +++ foo/drivers/ieee1394/csr1212.c @@ -388,101 +388,70 @@ csr1212_new_descriptor_leaf(u8 dtype, u3 CSR1212_DESCRIPTOR_LEAF_SET_TYPE(kv, dtype); CSR1212_DESCRIPTOR_LEAF_SET_SPECIFIER_ID(kv, specifier_id); - if (data) { + if (data) memcpy(CSR1212_DESCRIPTOR_LEAF_DATA(kv), data, data_len); - } - - return kv; -} - -#define CSR1212_TEXTUAL_DESCRIPTOR_LEAF_SET_WIDTH(kv, width) \ - ((kv)->value.leaf.data[1] = \ - ((kv)->value.leaf.data[1] & \ - cpu_to_be32(~(CSR1212_TEXTUAL_DESCRIPTOR_LEAF_WIDTH_MASK << \ - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_WIDTH_SHIFT))) | \ - cpu_to_be32(((width) & CSR1212_TEXTUAL_DESCRIPTOR_LEAF_WIDTH_MASK) << \ - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_WIDTH_SHIFT)) - -#define CSR1212_TEXTUAL_DESCRIPTOR_LEAF_SET_CHAR_SET(kv, char_set) \ - ((kv)->value.leaf.data[1] = \ - ((kv)->value.leaf.data[1] & \ - cpu_to_be32(~(CSR1212_TEXTUAL_DESCRIPTOR_LEAF_CHAR_SET_MASK << \ - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_CHAR_SET_SHIFT))) | \ - cpu_to_be32(((char_set) & \ - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_CHAR_SET_MASK) << \ - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_CHAR_SET_SHIFT)) - -#define CSR1212_TEXTUAL_DESCRIPTOR_LEAF_SET_LANGUAGE(kv, language) \ - ((kv)->value.leaf.data[1] = \ - ((kv)->value.leaf.data[1] & \ - cpu_to_be32(~(CSR1212_TEXTUAL_DESCRIPTOR_LEAF_LANGUAGE_MASK))) | \ - cpu_to_be32(((language) & \ - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_LANGUAGE_MASK))) - -static struct csr1212_keyval * -csr1212_new_textual_descriptor_leaf(u8 cwidth, u16 cset, u16 language, - const void *data, size_t data_len) -{ - struct csr1212_keyval *kv; - char *lstr; - - kv = csr1212_new_descriptor_leaf(0, 0, NULL, data_len + - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_OVERHEAD); - if (!kv) - return NULL; - - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_SET_WIDTH(kv, cwidth); - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_SET_CHAR_SET(kv, cset); - CSR1212_TEXTUAL_DESCRIPTOR_LEAF_SET_LANGUAGE(kv, language); - - lstr = (char*)CSR1212_TEXTUAL_DESCRIPTOR_LEAF_DATA(kv); - - /* make sure last quadlet is zeroed out */ - *((u32*)&(lstr[(data_len - 1) & ~0x3])) = 0; - - /* don't copy the NUL terminator */ - memcpy(lstr, data, data_len); return kv; } +/* Check if string conforms to minimal ASCII as per IEEE 1212 clause 7.4 */ static int csr1212_check_minimal_ascii(const char *s) { static const char minimal_ascii_table[] = { - 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x07, - 0x00, 0x00, 0x0a, 0x00, 0x0C, 0x0D, 0x00, 0x00, - 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, - 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, - 0x20, 0x21, 0x22, 0x00, 0x00, 0x25, 0x26, 0x27, - 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f, - 0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, - 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f, - 0x40, 0x41, 0x42, 0x43, 0x44, 0x45, 0x46, 0x47, - 0x48, 0x49, 0x4a, 0x4b, 0x4c, 0x4d, 0x4e, 0x4f, - 0x50, 0x51, 0x52, 0x53, 0x54, 0x55, 0x56, 0x57, - 0x58, 0x59, 0x5a, 0x00, 0x00, 0x00, 0x00, 0x5f, - 0x00, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, - 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f, - 0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, - 0x78, 0x79, 0x7a, 0x00, 0x00, 0x00, 0x00, 0x00, + /* 1 2 4 8 16 32 64 128 */ + 128, /* --, --, --, --, --, --, --, 07, */ + 4 + 16 + 32, /* --, --, 0a, --, 0C, 0D, --, --, */ + 0, /* --, --, --, --, --, --, --, --, */ + 0, /* --, --, --, --, --, --, --, --, */ + 255 - 8 - 16, /* 20, 21, 22, --, --, 25, 26, 27, */ + 255, /* 28, 29, 2a, 2b, 2c, 2d, 2e, 2f, */ + 255, /* 30, 31, 32, 33, 34, 35, 36, 37, */ + 255, /* 38, 39, 3a, 3b, 3c, 3d, 3e, 3f, */ + 255, /* 40, 41, 42, 43, 44, 45, 46, 47, */ + 255, /* 48, 49, 4a, 4b, 4c, 4d, 4e, 4f, */ + 255, /* 50, 51, 52, 53, 54, 55, 56, 57, */ + 1 + 2 + 4 + 128, /* 58, 59, 5a, --, --, --, --, 5f, */ + 255 - 1, /* --, 61, 62, 63, 64, 65, 66, 67, */ + 255, /* 68, 69, 6a, 6b, 6c, 6d, 6e, 6f, */ + 255, /* 70, 71, 72, 73, 74, 75, 76, 77, */ + 1 + 2 + 4, /* 78, 79, 7a, --, --, --, --, --, */ }; + int i, j; + for (; *s; s++) { - if (minimal_ascii_table[*s & 0x7F] != *s) - return -1; /* failed */ + i = *s >> 3; /* i = *s / 8; */ + j = 1 << (*s & 3); /* j = 1 << (*s % 8); */ + + if (i >= ARRAY_SIZE(minimal_ascii_table) || + !(minimal_ascii_table[i] & j)) + return -EINVAL; } - /* String conforms to minimal-ascii, as specified by IEEE 1212, - * par. 7.4 */ return 0; } +/* IEEE 1212 clause 7.5.4.1 textual descriptors (English, minimal ASCII) */ struct csr1212_keyval *csr1212_new_string_descriptor_leaf(const char *s) { - /* Check if string conform to minimal_ascii format */ - if (csr1212_check_minimal_ascii(s)) + struct csr1212_keyval *kv; + u32 *text; + size_t str_len, quads; + + if (!s || !*s || csr1212_check_minimal_ascii(s)) + return NULL; + + str_len = strlen(s); + quads = bytes_to_quads(str_len); + kv = csr1212_new_descriptor_leaf(0, 0, NULL, quads_to_bytes(quads) + + CSR1212_TEXTUAL_DESCRIPTOR_LEAF_OVERHEAD); + if (!kv) return NULL; - /* IEEE 1212, par. 7.5.4.1 Textual descriptors (minimal ASCII) */ - return csr1212_new_textual_descriptor_leaf(0, 0, 0, s, strlen(s)); + kv->value.leaf.data[1] = 0; /* width, character_set, language */ + text = CSR1212_TEXTUAL_DESCRIPTOR_LEAF_DATA(kv); + text[quads - 1] = 0; /* padding */ + memcpy(text, s, str_len); + + return kv; }