diff options
Diffstat (limited to 'reftable/record.c')
| -rw-r--r-- | reftable/record.c | 125 |
1 files changed, 59 insertions, 66 deletions
diff --git a/reftable/record.c b/reftable/record.c index 04429d23fe..8919df8a4d 100644 --- a/reftable/record.c +++ b/reftable/record.c @@ -21,47 +21,49 @@ static void *reftable_record_data(struct reftable_record *rec); int get_var_int(uint64_t *dest, struct string_view *in) { - int ptr = 0; + const unsigned char *buf = in->buf; + unsigned char c; uint64_t val; - if (in->len == 0) + if (!in->len) return -1; - val = in->buf[ptr] & 0x7f; - - while (in->buf[ptr] & 0x80) { - ptr++; - if (ptr > in->len) { + c = *buf++; + val = c & 0x7f; + + while (c & 0x80) { + /* + * We use a micro-optimization here: whenever we see that the + * 0x80 bit is set, we know that the remainder of the value + * cannot be 0. The zero-values thus doesn't need to be encoded + * at all, which is why we subtract 1 when encoding and add 1 + * when decoding. + * + * This allows us to save a byte in some edge cases. + */ + val += 1; + if (!val || (val & (uint64_t)(~0ULL << (64 - 7)))) + return -1; /* overflow */ + if (buf >= in->buf + in->len) return -1; - } - val = (val + 1) << 7 | (uint64_t)(in->buf[ptr] & 0x7f); + c = *buf++; + val = (val << 7) + (c & 0x7f); } *dest = val; - return ptr + 1; + return buf - in->buf; } -int put_var_int(struct string_view *dest, uint64_t val) +int put_var_int(struct string_view *dest, uint64_t value) { - uint8_t buf[10] = { 0 }; - int i = 9; - int n = 0; - buf[i] = (uint8_t)(val & 0x7f); - i--; - while (1) { - val >>= 7; - if (!val) { - break; - } - val--; - buf[i] = 0x80 | (uint8_t)(val & 0x7f); - i--; - } - - n = sizeof(buf) - i - 1; - if (dest->len < n) + unsigned char varint[10]; + unsigned pos = sizeof(varint) - 1; + varint[pos] = value & 0x7f; + while (value >>= 7) + varint[--pos] = 0x80 | (--value & 0x7f); + if (dest->len < sizeof(varint) - pos) return -1; - memcpy(dest->buf, &buf[i + 1], n); - return n; + memcpy(dest->buf, varint + pos, sizeof(varint) - pos); + return sizeof(varint) - pos; } int reftable_is_block_type(uint8_t typ) @@ -124,7 +126,7 @@ static int decode_string(struct reftable_buf *dest, struct string_view in) static int encode_string(const char *str, struct string_view s) { struct string_view start = s; - int l = strlen(str); + size_t l = strlen(str); int n = put_var_int(&s, l); if (n < 0) return -1; @@ -142,9 +144,9 @@ int reftable_encode_key(int *restart, struct string_view dest, uint8_t extra) { struct string_view start = dest; - int prefix_len = common_prefix_size(&prev_key, &key); + size_t prefix_len = common_prefix_size(&prev_key, &key); uint64_t suffix_len = key.len - prefix_len; - int n = put_var_int(&dest, (uint64_t)prefix_len); + int n = put_var_int(&dest, prefix_len); if (n < 0) return -1; string_view_consume(&dest, n); @@ -227,7 +229,7 @@ static int reftable_ref_record_key(const void *r, struct reftable_buf *dest) } static int reftable_ref_record_copy_from(void *rec, const void *src_rec, - int hash_size) + uint32_t hash_size) { struct reftable_ref_record *ref = rec; const struct reftable_ref_record *src = src_rec; @@ -235,8 +237,6 @@ static int reftable_ref_record_copy_from(void *rec, const void *src_rec, size_t refname_cap = 0; int err; - assert(hash_size > 0); - SWAP(refname, ref->refname); SWAP(refname_cap, ref->refname_cap); reftable_ref_record_release(ref); @@ -317,13 +317,12 @@ static uint8_t reftable_ref_record_val_type(const void *rec) } static int reftable_ref_record_encode(const void *rec, struct string_view s, - int hash_size) + uint32_t hash_size) { const struct reftable_ref_record *r = (const struct reftable_ref_record *)rec; struct string_view start = s; int n = put_var_int(&s, r->update_index); - assert(hash_size > 0); if (n < 0) return -1; string_view_consume(&s, n); @@ -363,7 +362,7 @@ static int reftable_ref_record_encode(const void *rec, struct string_view s, static int reftable_ref_record_decode(void *rec, struct reftable_buf key, uint8_t val_type, struct string_view in, - int hash_size, struct reftable_buf *scratch) + uint32_t hash_size, struct reftable_buf *scratch) { struct reftable_ref_record *r = rec; struct string_view start = in; @@ -372,8 +371,6 @@ static int reftable_ref_record_decode(void *rec, struct reftable_buf key, size_t refname_cap = 0; int n, err; - assert(hash_size > 0); - n = get_var_int(&update_index, &in); if (n < 0) return n; @@ -449,7 +446,7 @@ static int reftable_ref_record_is_deletion_void(const void *p) } static int reftable_ref_record_equal_void(const void *a, - const void *b, int hash_size) + const void *b, uint32_t hash_size) { struct reftable_ref_record *ra = (struct reftable_ref_record *) a; struct reftable_ref_record *rb = (struct reftable_ref_record *) b; @@ -493,7 +490,7 @@ static void reftable_obj_record_release(void *rec) } static int reftable_obj_record_copy_from(void *rec, const void *src_rec, - int hash_size UNUSED) + uint32_t hash_size UNUSED) { struct reftable_obj_record *obj = rec; const struct reftable_obj_record *src = src_rec; @@ -525,7 +522,7 @@ static uint8_t reftable_obj_record_val_type(const void *rec) } static int reftable_obj_record_encode(const void *rec, struct string_view s, - int hash_size UNUSED) + uint32_t hash_size UNUSED) { const struct reftable_obj_record *r = rec; struct string_view start = s; @@ -560,7 +557,7 @@ static int reftable_obj_record_encode(const void *rec, struct string_view s, static int reftable_obj_record_decode(void *rec, struct reftable_buf key, uint8_t val_type, struct string_view in, - int hash_size UNUSED, + uint32_t hash_size UNUSED, struct reftable_buf *scratch UNUSED) { struct string_view start = in; @@ -568,7 +565,6 @@ static int reftable_obj_record_decode(void *rec, struct reftable_buf key, uint64_t count = val_type; int n = 0; uint64_t last; - int j; reftable_obj_record_release(r); @@ -603,8 +599,7 @@ static int reftable_obj_record_decode(void *rec, struct reftable_buf key, string_view_consume(&in, n); last = r->offsets[0]; - j = 1; - while (j < count) { + for (uint64_t j = 1; j < count; j++) { uint64_t delta = 0; int n = get_var_int(&delta, &in); if (n < 0) { @@ -613,7 +608,6 @@ static int reftable_obj_record_decode(void *rec, struct reftable_buf key, string_view_consume(&in, n); last = r->offsets[j] = (delta + last); - j++; } return start.len - in.len; } @@ -624,7 +618,7 @@ static int not_a_deletion(const void *p UNUSED) } static int reftable_obj_record_equal_void(const void *a, const void *b, - int hash_size UNUSED) + uint32_t hash_size UNUSED) { struct reftable_obj_record *ra = (struct reftable_obj_record *) a; struct reftable_obj_record *rb = (struct reftable_obj_record *) b; @@ -699,7 +693,7 @@ static int reftable_log_record_key(const void *r, struct reftable_buf *dest) } static int reftable_log_record_copy_from(void *rec, const void *src_rec, - int hash_size) + uint32_t hash_size) { struct reftable_log_record *dst = rec; const struct reftable_log_record *src = @@ -780,7 +774,7 @@ static uint8_t reftable_log_record_val_type(const void *rec) } static int reftable_log_record_encode(const void *rec, struct string_view s, - int hash_size) + uint32_t hash_size) { const struct reftable_log_record *r = rec; struct string_view start = s; @@ -828,7 +822,7 @@ static int reftable_log_record_encode(const void *rec, struct string_view s, static int reftable_log_record_decode(void *rec, struct reftable_buf key, uint8_t val_type, struct string_view in, - int hash_size, struct reftable_buf *scratch) + uint32_t hash_size, struct reftable_buf *scratch) { struct string_view start = in; struct reftable_log_record *r = rec; @@ -976,7 +970,7 @@ static int null_streq(const char *a, const char *b) } static int reftable_log_record_equal_void(const void *a, - const void *b, int hash_size) + const void *b, uint32_t hash_size) { return reftable_log_record_equal((struct reftable_log_record *) a, (struct reftable_log_record *) b, @@ -1000,7 +994,7 @@ static int reftable_log_record_cmp_void(const void *_a, const void *_b) } int reftable_log_record_equal(const struct reftable_log_record *a, - const struct reftable_log_record *b, int hash_size) + const struct reftable_log_record *b, uint32_t hash_size) { if (!(null_streq(a->refname, b->refname) && a->update_index == b->update_index && @@ -1054,7 +1048,7 @@ static int reftable_index_record_key(const void *r, struct reftable_buf *dest) } static int reftable_index_record_copy_from(void *rec, const void *src_rec, - int hash_size UNUSED) + uint32_t hash_size UNUSED) { struct reftable_index_record *dst = rec; const struct reftable_index_record *src = src_rec; @@ -1081,7 +1075,7 @@ static uint8_t reftable_index_record_val_type(const void *rec UNUSED) } static int reftable_index_record_encode(const void *rec, struct string_view out, - int hash_size UNUSED) + uint32_t hash_size UNUSED) { const struct reftable_index_record *r = (const struct reftable_index_record *)rec; @@ -1099,7 +1093,7 @@ static int reftable_index_record_encode(const void *rec, struct string_view out, static int reftable_index_record_decode(void *rec, struct reftable_buf key, uint8_t val_type UNUSED, struct string_view in, - int hash_size UNUSED, + uint32_t hash_size UNUSED, struct reftable_buf *scratch UNUSED) { struct string_view start = in; @@ -1120,7 +1114,7 @@ static int reftable_index_record_decode(void *rec, struct reftable_buf key, } static int reftable_index_record_equal(const void *a, const void *b, - int hash_size UNUSED) + uint32_t hash_size UNUSED) { struct reftable_index_record *ia = (struct reftable_index_record *) a; struct reftable_index_record *ib = (struct reftable_index_record *) b; @@ -1154,14 +1148,14 @@ int reftable_record_key(struct reftable_record *rec, struct reftable_buf *dest) } int reftable_record_encode(struct reftable_record *rec, struct string_view dest, - int hash_size) + uint32_t hash_size) { return reftable_record_vtable(rec)->encode(reftable_record_data(rec), dest, hash_size); } int reftable_record_copy_from(struct reftable_record *rec, - struct reftable_record *src, int hash_size) + struct reftable_record *src, uint32_t hash_size) { assert(src->type == rec->type); @@ -1176,7 +1170,7 @@ uint8_t reftable_record_val_type(struct reftable_record *rec) } int reftable_record_decode(struct reftable_record *rec, struct reftable_buf key, - uint8_t extra, struct string_view src, int hash_size, + uint8_t extra, struct string_view src, uint32_t hash_size, struct reftable_buf *scratch) { return reftable_record_vtable(rec)->decode(reftable_record_data(rec), @@ -1203,7 +1197,7 @@ int reftable_record_cmp(struct reftable_record *a, struct reftable_record *b) reftable_record_data(a), reftable_record_data(b)); } -int reftable_record_equal(struct reftable_record *a, struct reftable_record *b, int hash_size) +int reftable_record_equal(struct reftable_record *a, struct reftable_record *b, uint32_t hash_size) { if (a->type != b->type) return 0; @@ -1211,7 +1205,7 @@ int reftable_record_equal(struct reftable_record *a, struct reftable_record *b, reftable_record_data(a), reftable_record_data(b), hash_size); } -static int hash_equal(const unsigned char *a, const unsigned char *b, int hash_size) +static int hash_equal(const unsigned char *a, const unsigned char *b, uint32_t hash_size) { if (a && b) return !memcmp(a, b, hash_size); @@ -1220,9 +1214,8 @@ static int hash_equal(const unsigned char *a, const unsigned char *b, int hash_s } int reftable_ref_record_equal(const struct reftable_ref_record *a, - const struct reftable_ref_record *b, int hash_size) + const struct reftable_ref_record *b, uint32_t hash_size) { - assert(hash_size > 0); if (!null_streq(a->refname, b->refname)) return 0; |