diff options
Diffstat (limited to 'reftable/record.c')
| -rw-r--r-- | reftable/record.c | 1212 |
1 files changed, 1212 insertions, 0 deletions
diff --git a/reftable/record.c b/reftable/record.c new file mode 100644 index 0000000..6a5dac3 --- /dev/null +++ b/reftable/record.c @@ -0,0 +1,1212 @@ +/* +Copyright 2020 Google LLC + +Use of this source code is governed by a BSD-style +license that can be found in the LICENSE file or at +https://developers.google.com/open-source/licenses/bsd +*/ + +/* record.c - methods for different types of records. */ + +#include "record.h" + +#include "system.h" +#include "constants.h" +#include "reftable-error.h" +#include "basics.h" + +int get_var_int(uint64_t *dest, struct string_view *in) +{ + int ptr = 0; + uint64_t val; + + if (in->len == 0) + return -1; + val = in->buf[ptr] & 0x7f; + + while (in->buf[ptr] & 0x80) { + ptr++; + if (ptr > in->len) { + return -1; + } + val = (val + 1) << 7 | (uint64_t)(in->buf[ptr] & 0x7f); + } + + *dest = val; + return ptr + 1; +} + +int put_var_int(struct string_view *dest, uint64_t val) +{ + 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) + return -1; + memcpy(dest->buf, &buf[i + 1], n); + return n; +} + +int reftable_is_block_type(uint8_t typ) +{ + switch (typ) { + case BLOCK_TYPE_REF: + case BLOCK_TYPE_LOG: + case BLOCK_TYPE_OBJ: + case BLOCK_TYPE_INDEX: + return 1; + } + return 0; +} + +uint8_t *reftable_ref_record_val1(struct reftable_ref_record *rec) +{ + switch (rec->value_type) { + case REFTABLE_REF_VAL1: + return rec->value.val1; + case REFTABLE_REF_VAL2: + return rec->value.val2.value; + default: + return NULL; + } +} + +uint8_t *reftable_ref_record_val2(struct reftable_ref_record *rec) +{ + switch (rec->value_type) { + case REFTABLE_REF_VAL2: + return rec->value.val2.target_value; + default: + return NULL; + } +} + +static int decode_string(struct strbuf *dest, struct string_view in) +{ + int start_len = in.len; + uint64_t tsize = 0; + int n = get_var_int(&tsize, &in); + if (n <= 0) + return -1; + string_view_consume(&in, n); + if (in.len < tsize) + return -1; + + strbuf_reset(dest); + strbuf_add(dest, in.buf, tsize); + string_view_consume(&in, tsize); + + return start_len - in.len; +} + +static int encode_string(char *str, struct string_view s) +{ + struct string_view start = s; + int l = strlen(str); + int n = put_var_int(&s, l); + if (n < 0) + return -1; + string_view_consume(&s, n); + if (s.len < l) + return -1; + memcpy(s.buf, str, l); + string_view_consume(&s, l); + + return start.len - s.len; +} + +int reftable_encode_key(int *restart, struct string_view dest, + struct strbuf prev_key, struct strbuf key, + uint8_t extra) +{ + struct string_view start = dest; + int 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); + if (n < 0) + return -1; + string_view_consume(&dest, n); + + *restart = (prefix_len == 0); + + n = put_var_int(&dest, suffix_len << 3 | (uint64_t)extra); + if (n < 0) + return -1; + string_view_consume(&dest, n); + + if (dest.len < suffix_len) + return -1; + memcpy(dest.buf, key.buf + prefix_len, suffix_len); + string_view_consume(&dest, suffix_len); + + return start.len - dest.len; +} + +int reftable_decode_key(struct strbuf *key, uint8_t *extra, + struct strbuf last_key, struct string_view in) +{ + int start_len = in.len; + uint64_t prefix_len = 0; + uint64_t suffix_len = 0; + int n = get_var_int(&prefix_len, &in); + if (n < 0) + return -1; + string_view_consume(&in, n); + + if (prefix_len > last_key.len) + return -1; + + n = get_var_int(&suffix_len, &in); + if (n <= 0) + return -1; + string_view_consume(&in, n); + + *extra = (uint8_t)(suffix_len & 0x7); + suffix_len >>= 3; + + if (in.len < suffix_len) + return -1; + + strbuf_reset(key); + strbuf_add(key, last_key.buf, prefix_len); + strbuf_add(key, in.buf, suffix_len); + string_view_consume(&in, suffix_len); + + return start_len - in.len; +} + +static void reftable_ref_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_ref_record *rec = + (const struct reftable_ref_record *)r; + strbuf_reset(dest); + strbuf_addstr(dest, rec->refname); +} + +static void reftable_ref_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_ref_record *ref = rec; + const struct reftable_ref_record *src = src_rec; + assert(hash_size > 0); + + /* This is simple and correct, but we could probably reuse the hash + * fields. */ + reftable_ref_record_release(ref); + if (src->refname) { + ref->refname = xstrdup(src->refname); + } + ref->update_index = src->update_index; + ref->value_type = src->value_type; + switch (src->value_type) { + case REFTABLE_REF_DELETION: + break; + case REFTABLE_REF_VAL1: + ref->value.val1 = reftable_malloc(hash_size); + memcpy(ref->value.val1, src->value.val1, hash_size); + break; + case REFTABLE_REF_VAL2: + ref->value.val2.value = reftable_malloc(hash_size); + memcpy(ref->value.val2.value, src->value.val2.value, hash_size); + ref->value.val2.target_value = reftable_malloc(hash_size); + memcpy(ref->value.val2.target_value, + src->value.val2.target_value, hash_size); + break; + case REFTABLE_REF_SYMREF: + ref->value.symref = xstrdup(src->value.symref); + break; + } +} + +static char hexdigit(int c) +{ + if (c <= 9) + return '0' + c; + return 'a' + (c - 10); +} + +static void hex_format(char *dest, uint8_t *src, int hash_size) +{ + assert(hash_size > 0); + if (src) { + int i = 0; + for (i = 0; i < hash_size; i++) { + dest[2 * i] = hexdigit(src[i] >> 4); + dest[2 * i + 1] = hexdigit(src[i] & 0xf); + } + dest[2 * hash_size] = 0; + } +} + +void reftable_ref_record_print(struct reftable_ref_record *ref, + uint32_t hash_id) +{ + char hex[2 * GIT_SHA256_RAWSZ + 1] = { 0 }; /* BUG */ + printf("ref{%s(%" PRIu64 ") ", ref->refname, ref->update_index); + switch (ref->value_type) { + case REFTABLE_REF_SYMREF: + printf("=> %s", ref->value.symref); + break; + case REFTABLE_REF_VAL2: + hex_format(hex, ref->value.val2.value, hash_size(hash_id)); + printf("val 2 %s", hex); + hex_format(hex, ref->value.val2.target_value, + hash_size(hash_id)); + printf("(T %s)", hex); + break; + case REFTABLE_REF_VAL1: + hex_format(hex, ref->value.val1, hash_size(hash_id)); + printf("val 1 %s", hex); + break; + case REFTABLE_REF_DELETION: + printf("delete"); + break; + } + printf("}\n"); +} + +static void reftable_ref_record_release_void(void *rec) +{ + reftable_ref_record_release(rec); +} + +void reftable_ref_record_release(struct reftable_ref_record *ref) +{ + switch (ref->value_type) { + case REFTABLE_REF_SYMREF: + reftable_free(ref->value.symref); + break; + case REFTABLE_REF_VAL2: + reftable_free(ref->value.val2.target_value); + reftable_free(ref->value.val2.value); + break; + case REFTABLE_REF_VAL1: + reftable_free(ref->value.val1); + break; + case REFTABLE_REF_DELETION: + break; + default: + abort(); + } + + reftable_free(ref->refname); + memset(ref, 0, sizeof(struct reftable_ref_record)); +} + +static uint8_t reftable_ref_record_val_type(const void *rec) +{ + const struct reftable_ref_record *r = + (const struct reftable_ref_record *)rec; + return r->value_type; +} + +static int reftable_ref_record_encode(const void *rec, struct string_view s, + int 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); + + switch (r->value_type) { + case REFTABLE_REF_SYMREF: + n = encode_string(r->value.symref, s); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + break; + case REFTABLE_REF_VAL2: + if (s.len < 2 * hash_size) { + return -1; + } + memcpy(s.buf, r->value.val2.value, hash_size); + string_view_consume(&s, hash_size); + memcpy(s.buf, r->value.val2.target_value, hash_size); + string_view_consume(&s, hash_size); + break; + case REFTABLE_REF_VAL1: + if (s.len < hash_size) { + return -1; + } + memcpy(s.buf, r->value.val1, hash_size); + string_view_consume(&s, hash_size); + break; + case REFTABLE_REF_DELETION: + break; + default: + abort(); + } + + return start.len - s.len; +} + +static int reftable_ref_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct reftable_ref_record *r = rec; + struct string_view start = in; + uint64_t update_index = 0; + int n = get_var_int(&update_index, &in); + if (n < 0) + return n; + string_view_consume(&in, n); + + reftable_ref_record_release(r); + + assert(hash_size > 0); + + r->refname = reftable_realloc(r->refname, key.len + 1); + memcpy(r->refname, key.buf, key.len); + r->update_index = update_index; + r->refname[key.len] = 0; + r->value_type = val_type; + switch (val_type) { + case REFTABLE_REF_VAL1: + if (in.len < hash_size) { + return -1; + } + + r->value.val1 = reftable_malloc(hash_size); + memcpy(r->value.val1, in.buf, hash_size); + string_view_consume(&in, hash_size); + break; + + case REFTABLE_REF_VAL2: + if (in.len < 2 * hash_size) { + return -1; + } + + r->value.val2.value = reftable_malloc(hash_size); + memcpy(r->value.val2.value, in.buf, hash_size); + string_view_consume(&in, hash_size); + + r->value.val2.target_value = reftable_malloc(hash_size); + memcpy(r->value.val2.target_value, in.buf, hash_size); + string_view_consume(&in, hash_size); + break; + + case REFTABLE_REF_SYMREF: { + struct strbuf dest = STRBUF_INIT; + int n = decode_string(&dest, in); + if (n < 0) { + return -1; + } + string_view_consume(&in, n); + r->value.symref = dest.buf; + } break; + + case REFTABLE_REF_DELETION: + break; + default: + abort(); + break; + } + + return start.len - in.len; +} + +static int reftable_ref_record_is_deletion_void(const void *p) +{ + return reftable_ref_record_is_deletion( + (const struct reftable_ref_record *)p); +} + +static struct reftable_record_vtable reftable_ref_record_vtable = { + .key = &reftable_ref_record_key, + .type = BLOCK_TYPE_REF, + .copy_from = &reftable_ref_record_copy_from, + .val_type = &reftable_ref_record_val_type, + .encode = &reftable_ref_record_encode, + .decode = &reftable_ref_record_decode, + .release = &reftable_ref_record_release_void, + .is_deletion = &reftable_ref_record_is_deletion_void, +}; + +static void reftable_obj_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_obj_record *rec = + (const struct reftable_obj_record *)r; + strbuf_reset(dest); + strbuf_add(dest, rec->hash_prefix, rec->hash_prefix_len); +} + +static void reftable_obj_record_release(void *rec) +{ + struct reftable_obj_record *obj = rec; + FREE_AND_NULL(obj->hash_prefix); + FREE_AND_NULL(obj->offsets); + memset(obj, 0, sizeof(struct reftable_obj_record)); +} + +static void reftable_obj_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_obj_record *obj = rec; + const struct reftable_obj_record *src = + (const struct reftable_obj_record *)src_rec; + + reftable_obj_record_release(obj); + *obj = *src; + obj->hash_prefix = reftable_malloc(obj->hash_prefix_len); + memcpy(obj->hash_prefix, src->hash_prefix, obj->hash_prefix_len); + + obj->offsets = reftable_malloc(obj->offset_len * sizeof(uint64_t)); + COPY_ARRAY(obj->offsets, src->offsets, obj->offset_len); +} + +static uint8_t reftable_obj_record_val_type(const void *rec) +{ + const struct reftable_obj_record *r = rec; + if (r->offset_len > 0 && r->offset_len < 8) + return r->offset_len; + return 0; +} + +static int reftable_obj_record_encode(const void *rec, struct string_view s, + int hash_size) +{ + const struct reftable_obj_record *r = rec; + struct string_view start = s; + int i = 0; + int n = 0; + uint64_t last = 0; + if (r->offset_len == 0 || r->offset_len >= 8) { + n = put_var_int(&s, r->offset_len); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + } + if (r->offset_len == 0) + return start.len - s.len; + n = put_var_int(&s, r->offsets[0]); + if (n < 0) + return -1; + string_view_consume(&s, n); + + last = r->offsets[0]; + for (i = 1; i < r->offset_len; i++) { + int n = put_var_int(&s, r->offsets[i] - last); + if (n < 0) { + return -1; + } + string_view_consume(&s, n); + last = r->offsets[i]; + } + return start.len - s.len; +} + +static int reftable_obj_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_obj_record *r = rec; + uint64_t count = val_type; + int n = 0; + uint64_t last; + int j; + r->hash_prefix = reftable_malloc(key.len); + memcpy(r->hash_prefix, key.buf, key.len); + r->hash_prefix_len = key.len; + + if (val_type == 0) { + n = get_var_int(&count, &in); + if (n < 0) { + return n; + } + + string_view_consume(&in, n); + } + + r->offsets = NULL; + r->offset_len = 0; + if (count == 0) + return start.len - in.len; + + r->offsets = reftable_malloc(count * sizeof(uint64_t)); + r->offset_len = count; + + n = get_var_int(&r->offsets[0], &in); + if (n < 0) + return n; + string_view_consume(&in, n); + + last = r->offsets[0]; + j = 1; + while (j < count) { + uint64_t delta = 0; + int n = get_var_int(&delta, &in); + if (n < 0) { + return n; + } + string_view_consume(&in, n); + + last = r->offsets[j] = (delta + last); + j++; + } + return start.len - in.len; +} + +static int not_a_deletion(const void *p) +{ + return 0; +} + +static struct reftable_record_vtable reftable_obj_record_vtable = { + .key = &reftable_obj_record_key, + .type = BLOCK_TYPE_OBJ, + .copy_from = &reftable_obj_record_copy_from, + .val_type = &reftable_obj_record_val_type, + .encode = &reftable_obj_record_encode, + .decode = &reftable_obj_record_decode, + .release = &reftable_obj_record_release, + .is_deletion = not_a_deletion, +}; + +void reftable_log_record_print(struct reftable_log_record *log, + uint32_t hash_id) +{ + char hex[GIT_SHA256_RAWSZ + 1] = { 0 }; + + switch (log->value_type) { + case REFTABLE_LOG_DELETION: + printf("log{%s(%" PRIu64 ") delete", log->refname, + log->update_index); + break; + case REFTABLE_LOG_UPDATE: + printf("log{%s(%" PRIu64 ") %s <%s> %" PRIu64 " %04d\n", + log->refname, log->update_index, log->value.update.name, + log->value.update.email, log->value.update.time, + log->value.update.tz_offset); + hex_format(hex, log->value.update.old_hash, hash_size(hash_id)); + printf("%s => ", hex); + hex_format(hex, log->value.update.new_hash, hash_size(hash_id)); + printf("%s\n\n%s\n}\n", hex, log->value.update.message); + break; + } +} + +static void reftable_log_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_log_record *rec = + (const struct reftable_log_record *)r; + int len = strlen(rec->refname); + uint8_t i64[8]; + uint64_t ts = 0; + strbuf_reset(dest); + strbuf_add(dest, (uint8_t *)rec->refname, len + 1); + + ts = (~ts) - rec->update_index; + put_be64(&i64[0], ts); + strbuf_add(dest, i64, sizeof(i64)); +} + +static void reftable_log_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_log_record *dst = rec; + const struct reftable_log_record *src = + (const struct reftable_log_record *)src_rec; + + reftable_log_record_release(dst); + *dst = *src; + if (dst->refname) { + dst->refname = xstrdup(dst->refname); + } + switch (dst->value_type) { + case REFTABLE_LOG_DELETION: + break; + case REFTABLE_LOG_UPDATE: + if (dst->value.update.email) { + dst->value.update.email = + xstrdup(dst->value.update.email); + } + if (dst->value.update.name) { + dst->value.update.name = + xstrdup(dst->value.update.name); + } + if (dst->value.update.message) { + dst->value.update.message = + xstrdup(dst->value.update.message); + } + + if (dst->value.update.new_hash) { + dst->value.update.new_hash = reftable_malloc(hash_size); + memcpy(dst->value.update.new_hash, + src->value.update.new_hash, hash_size); + } + if (dst->value.update.old_hash) { + dst->value.update.old_hash = reftable_malloc(hash_size); + memcpy(dst->value.update.old_hash, + src->value.update.old_hash, hash_size); + } + break; + } +} + +static void reftable_log_record_release_void(void *rec) +{ + struct reftable_log_record *r = rec; + reftable_log_record_release(r); +} + +void reftable_log_record_release(struct reftable_log_record *r) +{ + reftable_free(r->refname); + switch (r->value_type) { + case REFTABLE_LOG_DELETION: + break; + case REFTABLE_LOG_UPDATE: + reftable_free(r->value.update.new_hash); + reftable_free(r->value.update.old_hash); + reftable_free(r->value.update.name); + reftable_free(r->value.update.email); + reftable_free(r->value.update.message); + break; + } + memset(r, 0, sizeof(struct reftable_log_record)); +} + +static uint8_t reftable_log_record_val_type(const void *rec) +{ + const struct reftable_log_record *log = + (const struct reftable_log_record *)rec; + + return reftable_log_record_is_deletion(log) ? 0 : 1; +} + +static uint8_t zero[GIT_SHA256_RAWSZ] = { 0 }; + +static int reftable_log_record_encode(const void *rec, struct string_view s, + int hash_size) +{ + const struct reftable_log_record *r = rec; + struct string_view start = s; + int n = 0; + uint8_t *oldh = NULL; + uint8_t *newh = NULL; + if (reftable_log_record_is_deletion(r)) + return 0; + + oldh = r->value.update.old_hash; + newh = r->value.update.new_hash; + if (!oldh) { + oldh = zero; + } + if (!newh) { + newh = zero; + } + + if (s.len < 2 * hash_size) + return -1; + + memcpy(s.buf, oldh, hash_size); + memcpy(s.buf + hash_size, newh, hash_size); + string_view_consume(&s, 2 * hash_size); + + n = encode_string(r->value.update.name ? r->value.update.name : "", s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + n = encode_string(r->value.update.email ? r->value.update.email : "", + s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + n = put_var_int(&s, r->value.update.time); + if (n < 0) + return -1; + string_view_consume(&s, n); + + if (s.len < 2) + return -1; + + put_be16(s.buf, r->value.update.tz_offset); + string_view_consume(&s, 2); + + n = encode_string( + r->value.update.message ? r->value.update.message : "", s); + if (n < 0) + return -1; + string_view_consume(&s, n); + + return start.len - s.len; +} + +static int reftable_log_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_log_record *r = rec; + uint64_t max = 0; + uint64_t ts = 0; + struct strbuf dest = STRBUF_INIT; + int n; + + if (key.len <= 9 || key.buf[key.len - 9] != 0) + return REFTABLE_FORMAT_ERROR; + + r->refname = reftable_realloc(r->refname, key.len - 8); + memcpy(r->refname, key.buf, key.len - 8); + ts = get_be64(key.buf + key.len - 8); + + r->update_index = (~max) - ts; + + if (val_type != r->value_type) { + switch (r->value_type) { + case REFTABLE_LOG_UPDATE: + FREE_AND_NULL(r->value.update.old_hash); + FREE_AND_NULL(r->value.update.new_hash); + FREE_AND_NULL(r->value.update.message); + FREE_AND_NULL(r->value.update.email); + FREE_AND_NULL(r->value.update.name); + break; + case REFTABLE_LOG_DELETION: + break; + } + } + + r->value_type = val_type; + if (val_type == REFTABLE_LOG_DELETION) + return 0; + + if (in.len < 2 * hash_size) + return REFTABLE_FORMAT_ERROR; + + r->value.update.old_hash = + reftable_realloc(r->value.update.old_hash, hash_size); + r->value.update.new_hash = + reftable_realloc(r->value.update.new_hash, hash_size); + + memcpy(r->value.update.old_hash, in.buf, hash_size); + memcpy(r->value.update.new_hash, in.buf + hash_size, hash_size); + + string_view_consume(&in, 2 * hash_size); + + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->value.update.name = + reftable_realloc(r->value.update.name, dest.len + 1); + memcpy(r->value.update.name, dest.buf, dest.len); + r->value.update.name[dest.len] = 0; + + strbuf_reset(&dest); + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->value.update.email = + reftable_realloc(r->value.update.email, dest.len + 1); + memcpy(r->value.update.email, dest.buf, dest.len); + r->value.update.email[dest.len] = 0; + + ts = 0; + n = get_var_int(&ts, &in); + if (n < 0) + goto done; + string_view_consume(&in, n); + r->value.update.time = ts; + if (in.len < 2) + goto done; + + r->value.update.tz_offset = get_be16(in.buf); + string_view_consume(&in, 2); + + strbuf_reset(&dest); + n = decode_string(&dest, in); + if (n < 0) + goto done; + string_view_consume(&in, n); + + r->value.update.message = + reftable_realloc(r->value.update.message, dest.len + 1); + memcpy(r->value.update.message, dest.buf, dest.len); + r->value.update.message[dest.len] = 0; + + strbuf_release(&dest); + return start.len - in.len; + +done: + strbuf_release(&dest); + return REFTABLE_FORMAT_ERROR; +} + +static int null_streq(char *a, char *b) +{ + char *empty = ""; + if (!a) + a = empty; + + if (!b) + b = empty; + + return 0 == strcmp(a, b); +} + +static int zero_hash_eq(uint8_t *a, uint8_t *b, int sz) +{ + if (!a) + a = zero; + + if (!b) + b = zero; + + return !memcmp(a, b, sz); +} + +int reftable_log_record_equal(struct reftable_log_record *a, + struct reftable_log_record *b, int hash_size) +{ + if (!(null_streq(a->refname, b->refname) && + a->update_index == b->update_index && + a->value_type == b->value_type)) + return 0; + + switch (a->value_type) { + case REFTABLE_LOG_DELETION: + return 1; + case REFTABLE_LOG_UPDATE: + return null_streq(a->value.update.name, b->value.update.name) && + a->value.update.time == b->value.update.time && + a->value.update.tz_offset == b->value.update.tz_offset && + null_streq(a->value.update.email, + b->value.update.email) && + null_streq(a->value.update.message, + b->value.update.message) && + zero_hash_eq(a->value.update.old_hash, + b->value.update.old_hash, hash_size) && + zero_hash_eq(a->value.update.new_hash, + b->value.update.new_hash, hash_size); + } + + abort(); +} + +static int reftable_log_record_is_deletion_void(const void *p) +{ + return reftable_log_record_is_deletion( + (const struct reftable_log_record *)p); +} + +static struct reftable_record_vtable reftable_log_record_vtable = { + .key = &reftable_log_record_key, + .type = BLOCK_TYPE_LOG, + .copy_from = &reftable_log_record_copy_from, + .val_type = &reftable_log_record_val_type, + .encode = &reftable_log_record_encode, + .decode = &reftable_log_record_decode, + .release = &reftable_log_record_release_void, + .is_deletion = &reftable_log_record_is_deletion_void, +}; + +struct reftable_record reftable_new_record(uint8_t typ) +{ + struct reftable_record rec = { NULL }; + switch (typ) { + case BLOCK_TYPE_REF: { + struct reftable_ref_record *r = + reftable_calloc(sizeof(struct reftable_ref_record)); + reftable_record_from_ref(&rec, r); + return rec; + } + + case BLOCK_TYPE_OBJ: { + struct reftable_obj_record *r = + reftable_calloc(sizeof(struct reftable_obj_record)); + reftable_record_from_obj(&rec, r); + return rec; + } + case BLOCK_TYPE_LOG: { + struct reftable_log_record *r = + reftable_calloc(sizeof(struct reftable_log_record)); + reftable_record_from_log(&rec, r); + return rec; + } + case BLOCK_TYPE_INDEX: { + struct reftable_index_record empty = { .last_key = + STRBUF_INIT }; + struct reftable_index_record *r = + reftable_calloc(sizeof(struct reftable_index_record)); + *r = empty; + reftable_record_from_index(&rec, r); + return rec; + } + } + abort(); + return rec; +} + +/* clear out the record, yielding the reftable_record data that was + * encapsulated. */ +static void *reftable_record_yield(struct reftable_record *rec) +{ + void *p = rec->data; + rec->data = NULL; + return p; +} + +void reftable_record_destroy(struct reftable_record *rec) +{ + reftable_record_release(rec); + reftable_free(reftable_record_yield(rec)); +} + +static void reftable_index_record_key(const void *r, struct strbuf *dest) +{ + const struct reftable_index_record *rec = r; + strbuf_reset(dest); + strbuf_addbuf(dest, &rec->last_key); +} + +static void reftable_index_record_copy_from(void *rec, const void *src_rec, + int hash_size) +{ + struct reftable_index_record *dst = rec; + const struct reftable_index_record *src = src_rec; + + strbuf_reset(&dst->last_key); + strbuf_addbuf(&dst->last_key, &src->last_key); + dst->offset = src->offset; +} + +static void reftable_index_record_release(void *rec) +{ + struct reftable_index_record *idx = rec; + strbuf_release(&idx->last_key); +} + +static uint8_t reftable_index_record_val_type(const void *rec) +{ + return 0; +} + +static int reftable_index_record_encode(const void *rec, struct string_view out, + int hash_size) +{ + const struct reftable_index_record *r = + (const struct reftable_index_record *)rec; + struct string_view start = out; + + int n = put_var_int(&out, r->offset); + if (n < 0) + return n; + + string_view_consume(&out, n); + + return start.len - out.len; +} + +static int reftable_index_record_decode(void *rec, struct strbuf key, + uint8_t val_type, struct string_view in, + int hash_size) +{ + struct string_view start = in; + struct reftable_index_record *r = rec; + int n = 0; + + strbuf_reset(&r->last_key); + strbuf_addbuf(&r->last_key, &key); + + n = get_var_int(&r->offset, &in); + if (n < 0) + return n; + + string_view_consume(&in, n); + return start.len - in.len; +} + +static struct reftable_record_vtable reftable_index_record_vtable = { + .key = &reftable_index_record_key, + .type = BLOCK_TYPE_INDEX, + .copy_from = &reftable_index_record_copy_from, + .val_type = &reftable_index_record_val_type, + .encode = &reftable_index_record_encode, + .decode = &reftable_index_record_decode, + .release = &reftable_index_record_release, + .is_deletion = ¬_a_deletion, +}; + +void reftable_record_key(struct reftable_record *rec, struct strbuf *dest) +{ + rec->ops->key(rec->data, dest); +} + +uint8_t reftable_record_type(struct reftable_record *rec) +{ + return rec->ops->type; +} + +int reftable_record_encode(struct reftable_record *rec, struct string_view dest, + int hash_size) +{ + return rec->ops->encode(rec->data, dest, hash_size); +} + +void reftable_record_copy_from(struct reftable_record *rec, + struct reftable_record *src, int hash_size) +{ + assert(src->ops->type == rec->ops->type); + + rec->ops->copy_from(rec->data, src->data, hash_size); +} + +uint8_t reftable_record_val_type(struct reftable_record *rec) +{ + return rec->ops->val_type(rec->data); +} + +int reftable_record_decode(struct reftable_record *rec, struct strbuf key, + uint8_t extra, struct string_view src, int hash_size) +{ + return rec->ops->decode(rec->data, key, extra, src, hash_size); +} + +void reftable_record_release(struct reftable_record *rec) +{ + rec->ops->release(rec->data); +} + +int reftable_record_is_deletion(struct reftable_record *rec) +{ + return rec->ops->is_deletion(rec->data); +} + +void reftable_record_from_ref(struct reftable_record *rec, + struct reftable_ref_record *ref_rec) +{ + assert(!rec->ops); + rec->data = ref_rec; + rec->ops = &reftable_ref_record_vtable; +} + +void reftable_record_from_obj(struct reftable_record *rec, + struct reftable_obj_record *obj_rec) +{ + assert(!rec->ops); + rec->data = obj_rec; + rec->ops = &reftable_obj_record_vtable; +} + +void reftable_record_from_index(struct reftable_record *rec, + struct reftable_index_record *index_rec) +{ + assert(!rec->ops); + rec->data = index_rec; + rec->ops = &reftable_index_record_vtable; +} + +void reftable_record_from_log(struct reftable_record *rec, + struct reftable_log_record *log_rec) +{ + assert(!rec->ops); + rec->data = log_rec; + rec->ops = &reftable_log_record_vtable; +} + +struct reftable_ref_record *reftable_record_as_ref(struct reftable_record *rec) +{ + assert(reftable_record_type(rec) == BLOCK_TYPE_REF); + return rec->data; +} + +struct reftable_log_record *reftable_record_as_log(struct reftable_record *rec) +{ + assert(reftable_record_type(rec) == BLOCK_TYPE_LOG); + return rec->data; +} + +static int hash_equal(uint8_t *a, uint8_t *b, int hash_size) +{ + if (a && b) + return !memcmp(a, b, hash_size); + + return a == b; +} + +int reftable_ref_record_equal(struct reftable_ref_record *a, + struct reftable_ref_record *b, int hash_size) +{ + assert(hash_size > 0); + if (!(0 == strcmp(a->refname, b->refname) && + a->update_index == b->update_index && + a->value_type == b->value_type)) + return 0; + + switch (a->value_type) { + case REFTABLE_REF_SYMREF: + return !strcmp(a->value.symref, b->value.symref); + case REFTABLE_REF_VAL2: + return hash_equal(a->value.val2.value, b->value.val2.value, + hash_size) && + hash_equal(a->value.val2.target_value, + b->value.val2.target_value, hash_size); + case REFTABLE_REF_VAL1: + return hash_equal(a->value.val1, b->value.val1, hash_size); + case REFTABLE_REF_DELETION: + return 1; + default: + abort(); + } +} + +int reftable_ref_record_compare_name(const void *a, const void *b) +{ + return strcmp(((struct reftable_ref_record *)a)->refname, + ((struct reftable_ref_record *)b)->refname); +} + +int reftable_ref_record_is_deletion(const struct reftable_ref_record *ref) +{ + return ref->value_type == REFTABLE_REF_DELETION; +} + +int reftable_log_record_compare_key(const void *a, const void *b) +{ + const struct reftable_log_record *la = a; + const struct reftable_log_record *lb = b; + + int cmp = strcmp(la->refname, lb->refname); + if (cmp) + return cmp; + if (la->update_index > lb->update_index) + return -1; + return (la->update_index < lb->update_index) ? 1 : 0; +} + +int reftable_log_record_is_deletion(const struct reftable_log_record *log) +{ + return (log->value_type == REFTABLE_LOG_DELETION); +} + +void string_view_consume(struct string_view *s, int n) +{ + s->buf += n; + s->len -= n; +} |