diff options
Diffstat (limited to 'prototypes/connections/module-save.c')
| -rw-r--r-- | prototypes/connections/module-save.c | 488 |
1 files changed, 0 insertions, 488 deletions
diff --git a/prototypes/connections/module-save.c b/prototypes/connections/module-save.c deleted file mode 100644 index 4149316..0000000 --- a/prototypes/connections/module-save.c +++ /dev/null @@ -1,488 +0,0 @@ -#include "module-save.h" -#include "module-text.h" -#include <math.h> -#include <stdio.h> -#include <stdlib.h> -#include <string.h> - -/* Stored forms. values: "PVS1", then per state {u8 type, u8 name length, - * name, binary64 bits (little-endian)}. A list: "PLS1", u8 field count, per - * field {u8 0 number | 1 text, u8 name length, name}, then its items - * (module-list.h). A text state: its UTF-8 bytes. */ -static const unsigned char values_magic[4] = {'P', 'V', 'S', '1'}, list_magic[4] = {'P', 'L', 'S', '1'}; -/* links: "PLK1"; u8 outputs, each {u8 name length, name, u8 field count, the - * fields' types, u64le last number} (the module's outputs, then those it - * dropped, without fields); u16le sources, each {u8 length, the name, u64le - * last number heard}; then the sent messages to the end, each {u8 output (in - * the table), u64le number, u32le size, payload}. */ -static const unsigned char links_magic[4] = {'P', 'L', 'K', '1'}; -static const PureVersion unsaved = {UINT64_MAX, UINT64_MAX}; - -bool pure_save_enabled(const PureApp *app) { return app->data.state && app->data.save; } - -static PureResult open_state(PureApp *app, const char *prefix, const char *name, PureDraft **out) { - char key[64]; - snprintf(key, sizeof(key), "%s%s", prefix, name); - return app->data.state(app->data.context, key, out); -} - -/* The whole value of a draft, contiguous; free it. */ -typedef struct { unsigned char *bytes; size_t used; } Whole; - -static bool gather(void *context, PureSpan span) { - Whole *w = context; - memcpy(w->bytes + w->used, span.data, span.size); - w->used += span.size; - return true; -} - -static PureResult read_whole(const PureDraft *draft, unsigned char **out, size_t *size) { - *size = pure_draft_size(draft); - Whole w = {malloc(*size ? *size : 1), 0}; - if (!w.bytes) return PURE_ALLOCATION; - PureResult result = pure_draft_read(draft, 0, *size, gather, &w); - if (result != PURE_OK) { free(w.bytes); return result; } - *out = w.bytes; - return PURE_OK; -} - -/* One named entry of a stored form: u8 kind, u8 name length, the name (an - * identifier), then width more bytes. */ -PURE_COLD static bool named(const unsigned char *bytes, size_t size, size_t *at, size_t width, uint8_t *kind, - char name[PURE_MODULE_NAME]) { - if (size - *at < 2) return false; - size_t length = bytes[*at + 1]; - if (size - *at - 2 < length + width || !length || length >= PURE_MODULE_NAME) return false; - for (size_t i = 0; i < length; ++i) { - unsigned char c = bytes[*at + 2 + i]; - bool letter = (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_'; - if (!letter && !(i && c >= '0' && c <= '9')) return false; - } - *kind = bytes[*at]; - memcpy(name, bytes + *at + 2, length); - name[length] = 0; - *at += 2 + length; - return true; -} - -PURE_COLD PureResult pure_save_open_text(PureApp *app, const PureModule *m, uint32_t state, PureDraft **out, - PureVersion *saved) { - PureResult result = open_state(app, "text-", m->state_names[state], out); - if (result != PURE_OK) return result; - *saved = pure_draft_version(*out); - if (!pure_draft_revision(*out)) { - uint32_t constant = m->state_ref[state]; - PureSpan initial = {m->constant_data + m->constant_offset[constant], m->constant_length[constant]}; - result = pure_draft_splice(*out, 0, pure_draft_size(*out), initial); - *saved = unsaved; - } else { - unsigned char *bytes; - size_t size; - result = read_whole(*out, &bytes, &size); - if (result == PURE_OK) { - if (!pure_utf8_valid((PureSpan){bytes, size})) result = PURE_STORE_ERROR; - free(bytes); - } - } - if (result != PURE_OK) { pure_draft_close(*out); *out = NULL; } - return result; -} - -static size_t list_header(const PureModule *m, uint32_t record, unsigned char *out) { - const PureRecord *r = &m->record[record]; - size_t at = 0; - memcpy(out, list_magic, 4); - at = 4; - out[at++] = (unsigned char)r->count; - for (unsigned f = 0; f < r->count; ++f) { - const char *name = m->record_field_names[r->first + f]; - out[at++] = m->record_field_text[r->first + f]; - out[at++] = (unsigned char)strlen(name); - memcpy(out + at, name, strlen(name)); - at += strlen(name); - } - return at; -} - -PURE_COLD PureResult pure_save_rewrite_list(const PureModule *m, uint32_t state, PureList *list, PureDraft *draft) { - unsigned char header[5 + PURE_RECORD_FIELDS * (2 + PURE_MODULE_NAME)]; - size_t length = list_header(m, m->state_ref[state], header); - PureVersion before = pure_draft_version(draft); - pure_draft_hold(draft, true); - PureResult result = pure_draft_splice(draft, 0, pure_draft_size(draft), (PureSpan){header, length}); - pure_list_mirror(list, draft, length); - if (result == PURE_OK) result = pure_list_write(list); - if (result != PURE_OK) { - pure_draft_restore(draft, before); - pure_list_mirror(list, NULL, 0); - } - pure_draft_hold(draft, false); - return result; -} - -PURE_COLD PureResult pure_save_open_list(PureApp *app, const PureModule *m, uint32_t state, PureList **out, PureDraft **draft, - PureVersion *saved) { - uint32_t record = m->state_ref[state]; - const PureRecord *r = &m->record[record]; - *out = NULL; - PureResult result = open_state(app, "list-", m->state_names[state], draft); - if (result != PURE_OK) return result; - unsigned char *bytes = NULL; - size_t size = 0; - if (pure_draft_revision(*draft)) result = read_whole(*draft, &bytes, &size); - /* The stored record: its fields' kinds and names. */ - char names[PURE_RECORD_FIELDS][PURE_MODULE_NAME] = {{0}}; - uint8_t text[PURE_RECORD_FIELDS] = {0}; - unsigned count = 0; - size_t at = 0; - bool stored = result == PURE_OK && bytes; - if (stored) { - bool ok = size >= 5 && !memcmp(bytes, list_magic, 4) && bytes[4] <= PURE_RECORD_FIELDS; - count = ok ? bytes[4] : 0; - at = 5; - for (unsigned f = 0; ok && f < count; ++f) { - ok = named(bytes, size, &at, 0, &text[f], names[f]) && text[f] <= 1; - for (unsigned k = 0; k < f; ++k) ok = ok && strcmp(names[k], names[f]); - } - if (!ok) result = PURE_STORE_ERROR; - } - PureList *from = NULL; - if (result == PURE_OK && stored) { - from = pure_list_new(count, text); - result = from ? pure_list_read(from, bytes + at, size - at) : PURE_ALLOCATION; - } - free(bytes); - bool same = stored && count == r->count; - for (unsigned f = 0; same && f < count; ++f) - same = text[f] == m->record_field_text[r->first + f] && !strcmp(names[f], m->record_field_names[r->first + f]); - if (result == PURE_OK && same) { - *out = from; - pure_list_mirror(from, *draft, at); - *saved = pure_draft_version(*draft); - return PURE_OK; - } - if (result == PURE_OK) { - /* New, or stored with another record: its items move by field name. */ - const char *field_names[PURE_RECORD_FIELDS]; - for (unsigned f = 0; f < count; ++f) field_names[f] = names[f]; - if (from) result = pure_list_migrate(out, from, field_names, text, count, m, record); - else if (!(*out = pure_list_new(r->count, m->record_field_text + r->first))) result = PURE_ALLOCATION; - } - pure_list_free(from); - if (result == PURE_OK) result = pure_save_rewrite_list(m, state, *out, *draft); - if (result != PURE_OK) { - pure_list_free(*out); - pure_draft_close(*draft); - *out = NULL; - *draft = NULL; - return result; - } - *saved = unsaved; - return PURE_OK; -} - -static bool scalar(uint8_t type) { - return type == PURE_STATE_NUM || type == PURE_STATE_CURSOR || type == PURE_STATE_INDEX; -} - -/* A stored value still fits its state: a cursor on a character boundary of - * its text, an index on an item of its list (or 0), a finite number. */ -PURE_COLD static bool fits(const PureModule *m, PureDraft *const *texts, PureList *const *lists, uint32_t state, double value) { - if (!isfinite(value)) return false; - if (m->state_type[state] == PURE_STATE_NUM) return true; - if (value < 0 || value != floor(value)) return false; - if (m->state_type[state] == PURE_STATE_INDEX) { - size_t count = pure_list_count(lists[m->state_ref[state]]); - return value <= (count ? (double)(count - 1) : 0); - } - const PureDraft *text = texts[m->state_ref[state]]; - size_t size = pure_draft_size(text), at = (size_t)value; - if (value > (double)size) return false; - if (at == size) return true; - unsigned char byte = 0; - Whole w = {&byte, 0}; - return pure_draft_read(text, at, 1, gather, &w) == PURE_OK && (byte & 0xC0) != 0x80; -} - -static size_t encode_values(const PureModule *m, const double *values, unsigned char *out) { - size_t at = 4; - memcpy(out, values_magic, 4); - for (uint32_t i = 0; i < m->states; ++i) { - if (!scalar(m->state_type[i])) continue; - size_t length = strlen(m->state_names[i]); - uint64_t bits; - memcpy(&bits, &values[i], sizeof(bits)); - out[at++] = m->state_type[i]; - out[at++] = (unsigned char)length; - memcpy(out + at, m->state_names[i], length); - at += length; - for (unsigned b = 0; b < 8; ++b) out[at++] = (unsigned char)(bits >> (8 * b)); - } - return at; -} - -enum { VALUES_BYTES = 4 + PURE_MODULE_STATES * (2 + PURE_MODULE_NAME + 8) }; - -PURE_COLD PureResult pure_save_open_values(PureApp *app, const PureModule *m, double *values, const int *kept, - PureDraft *const *texts, PureList *const *lists) { - bool scalars = false, fresh = false; - for (uint32_t i = 0; i < m->states; ++i) - if (scalar(m->state_type[i])) { - scalars = true; - fresh = fresh || kept[i] < 0; - } - if (!scalars) return PURE_OK; - PureResult result = app->stored_values ? PURE_OK : open_state(app, "", "values", &app->stored_values); - if (result != PURE_OK || !fresh || !pure_draft_revision(app->stored_values)) return result; - unsigned char *bytes; - size_t size; - if ((result = read_whole(app->stored_values, &bytes, &size)) != PURE_OK) return result; - bool ok = size >= 4 && !memcmp(bytes, values_magic, 4); - for (size_t at = 4; ok && at < size;) { - char name[PURE_MODULE_NAME]; - uint8_t type; - if (!(ok = named(bytes, size, &at, 8, &type, name))) break; - uint64_t bits = 0; - for (unsigned b = 0; b < 8; ++b) bits |= (uint64_t)bytes[at + b] << (8 * b); - at += 8; - double value; - memcpy(&value, &bits, sizeof(value)); - int state = pure_module_state(m, name); - if (state >= 0 && kept[state] < 0 && m->state_type[state] == type && scalar(type) && - fits(m, texts, lists, (uint32_t)state, value)) - values[state] = value; - } - free(bytes); - return ok ? PURE_OK : PURE_STORE_ERROR; -} - -static bool same_version(PureVersion a, PureVersion b) { return a.ref == b.ref && a.bytes == b.bytes; } - -static unsigned char *put_le(unsigned char *at, uint64_t value, unsigned width) { - for (unsigned i = 0; i < width; ++i) *at++ = (unsigned char)(value >> (8 * i)); - return at; -} - -static uint64_t get_le(const unsigned char *at, unsigned width) { - uint64_t value = 0; - for (unsigned i = 0; i < width; ++i) value |= (uint64_t)at[i] << (8 * i); - return value; -} - -/* The links as stored; NULL when memory runs out. */ -static unsigned char *encode_links(const PureApp *app, size_t *size) { - const PureModule *m = app->module; - unsigned outputs = 0; - uint8_t table[PURE_MODULE_INPUTS]; - size_t total = 4 + 1 + 2; - for (uint32_t i = 0; i < m->inputs; ++i) - if (m->input[i].kind == PURE_KIND_OUTPUT) { - table[i] = (uint8_t)outputs++; - total += 2 + strlen(m->input_names[i]) + m->input[i].field_count + 8; - } - for (unsigned c = 0; c < app->carried_count; ++c) total += 2 + strlen(app->carried[c].name) + 8; - for (unsigned h = 0; h < app->heard_count; ++h) total += 1 + strlen(app->heard[h].source) + 8; - for (size_t s = 0; s < app->sent_count; ++s) - if (!app->sent[s].trimmed) total += 1 + 8 + 4 + app->sent[s].size; - unsigned char *bytes = malloc(total), *at = bytes; - if (!bytes) return NULL; - memcpy(at, links_magic, 4); - at += 4; - *at++ = (unsigned char)(outputs + app->carried_count); - for (uint32_t i = 0; i < m->inputs; ++i) { - if (m->input[i].kind != PURE_KIND_OUTPUT) continue; - size_t length = strlen(m->input_names[i]); - *at++ = (unsigned char)length; - memcpy(at, m->input_names[i], length); - at += length; - *at++ = (unsigned char)m->input[i].field_count; - for (uint32_t f = 0; f < m->input[i].field_count; ++f) *at++ = m->field[m->input[i].field_start + f].type; - at = put_le(at, app->last_sent[i], 8); - } - for (unsigned c = 0; c < app->carried_count; ++c) { - size_t length = strlen(app->carried[c].name); - *at++ = (unsigned char)length; - memcpy(at, app->carried[c].name, length); - at += length; - *at++ = 0; - at = put_le(at, app->carried[c].last, 8); - } - at = put_le(at, app->heard_count, 2); - for (unsigned h = 0; h < app->heard_count; ++h) { - size_t length = strlen(app->heard[h].source); - *at++ = (unsigned char)length; - memcpy(at, app->heard[h].source, length); - at = put_le(at + length, app->heard[h].seq, 8); - } - for (size_t s = 0; s < app->sent_count; ++s) { - const struct PureSent *sent = &app->sent[s]; - if (sent->trimmed) continue; - *at++ = table[sent->output]; - at = put_le(at, sent->seq, 8); - at = put_le(at, sent->size, 4); - if (sent->size) memcpy(at, sent->payload, sent->size); - at += sent->size; - } - *size = (size_t)(at - bytes); - return bytes; -} - -/* The stored links of a starting app: outputs by name (an output whose - * fields changed or that the module lacks refuses the start while it has - * sends left: CONFLICT; one without sends keeps its number for later), - * sources and sent messages. */ -PURE_COLD PureResult pure_save_open_links(PureApp *app, const PureModule *m) { - PureResult result = app->stored_links ? PURE_OK : open_state(app, "", "links", &app->stored_links); - if (result != PURE_OK || !pure_draft_revision(app->stored_links)) return result; - unsigned char *bytes; - size_t size; - if ((result = read_whole(app->stored_links, &bytes, &size)) != PURE_OK) return result; - int output[256]; - bool fits[256]; - size_t at = 5; - unsigned outputs = size >= 5 && !memcmp(bytes, links_magic, 4) ? bytes[4] : 0; - result = size >= 5 && !memcmp(bytes, links_magic, 4) ? PURE_OK : PURE_STORE_ERROR; - for (unsigned t = 0; t < outputs && result == PURE_OK; ++t) { - char name[PURE_MODULE_NAME]; - size_t length = at < size ? bytes[at] : 0; - if (!length || length >= PURE_MODULE_NAME || size - at < 2 + length) { result = PURE_STORE_ERROR; break; } - memcpy(name, bytes + at + 1, length); - name[length] = 0; - unsigned fields = bytes[at + 1 + length]; - at += 2 + length; - if (size - at < fields + 8) { result = PURE_STORE_ERROR; break; } - int i = pure_module_input(m, name); - output[t] = i >= 0 && m->input[i].kind == PURE_KIND_OUTPUT ? i : -1; - fits[t] = output[t] >= 0 && m->input[i].field_count == fields; - for (unsigned f = 0; fits[t] && f < fields; ++f) fits[t] = m->field[m->input[i].field_start + f].type == bytes[at + f]; - uint64_t last = get_le(bytes + at + fields, 8); - at += fields + 8; - if (output[t] >= 0) app->last_sent[output[t]] = last; - else if (last) { - struct PureCarried *grown = realloc(app->carried, (app->carried_count + 1) * sizeof(*grown)); - if (!grown) { result = PURE_ALLOCATION; break; } - app->carried = grown; - memcpy(grown[app->carried_count].name, name, length + 1); - grown[app->carried_count++].last = last; - } - } - unsigned sources = result == PURE_OK && size - at >= 2 ? (unsigned)get_le(bytes + at, 2) : 0; - if (result == PURE_OK && size - at < 2) result = PURE_STORE_ERROR; - at += 2; - if (result == PURE_OK && sources && !(app->heard = calloc(sources, sizeof(*app->heard)))) result = PURE_ALLOCATION; - app->heard_capacity = sources; - for (unsigned h = 0; h < sources && result == PURE_OK; ++h) { - size_t length = at < size ? bytes[at] : 0; - if (!length || length > PURE_SOURCE || size - at < 1 + length + 8) { result = PURE_STORE_ERROR; break; } - struct PureHeard *heard = &app->heard[app->heard_count++]; - memcpy(heard->source, bytes + at + 1, length); - heard->seq = heard->saved = get_le(bytes + at + 1 + length, 8); - at += 1 + length + 8; - } - while (result == PURE_OK && at < size) { - if (size - at < 13 || bytes[at] >= outputs) { result = PURE_STORE_ERROR; break; } - unsigned t = bytes[at]; - uint64_t seq = get_le(bytes + at + 1, 8); - size_t length = (size_t)get_le(bytes + at + 9, 4); - at += 13; - if (size - at < length) { result = PURE_STORE_ERROR; break; } - if (!fits[t]) { result = PURE_CONFLICT; break; } - if (app->sent_count == app->sent_capacity) { - size_t capacity = app->sent_capacity ? 2 * app->sent_capacity : 16; - struct PureSent *grown = realloc(app->sent, capacity * sizeof(*grown)); - if (!grown) { result = PURE_ALLOCATION; break; } - app->sent = grown; - app->sent_capacity = capacity; - } - unsigned char *payload = malloc(length ? length : 1); - if (!payload) { result = PURE_ALLOCATION; break; } - if (length) memcpy(payload, bytes + at, length); - app->sent[app->sent_count++] = (struct PureSent){(uint32_t)output[t], seq, payload, length, false}; - at += length; - } - free(bytes); - app->sent_durable = app->sent_count; - memcpy(app->saved_sent, app->last_sent, sizeof(app->saved_sent)); - return result; -} - -PureResult pure_save_commit(PureApp *app, const double *values, void *const *documents, size_t document_count, - int64_t *revisions) { - if (!pure_save_enabled(app)) { - /* Without a host that saves together, a save has one document at most. */ - PureResult result = PURE_OK; - for (size_t i = 0; i < document_count && result == PURE_OK; ++i) - result = app->data.commit(app->data.context, documents[i], &revisions[i]); - return result; - } - const PureModule *m = app->module; - PureDraft *drafts[2 * PURE_MODULE_STATES + 2]; - uint32_t states[2 * PURE_MODULE_STATES + 2]; - size_t count = 0; - for (uint32_t i = 0; i < m->states; ++i) { - PureDraft *draft = m->state_type[i] == PURE_STATE_TEXT ? app->texts[i] : - m->state_type[i] == PURE_STATE_LIST ? app->list_drafts[i] : NULL; - if (draft && !same_version(pure_draft_version(draft), app->saved[i])) { - states[count] = i; - drafts[count++] = draft; - } - } - /* Numbers, cursors and indices: stored again only when their bytes change. */ - PureVersion values_before = {0, 0}; - bool values_changed = false; - if (app->stored_values) { - unsigned char encoded[VALUES_BYTES], *stored; - size_t length = encode_values(m, values, encoded), size; - PureResult result = read_whole(app->stored_values, &stored, &size); - if (result != PURE_OK) return result; - values_changed = size != length || memcmp(stored, encoded, length); - free(stored); - if (values_changed) { - values_before = pure_draft_version(app->stored_values); - pure_draft_hold(app->stored_values, true); - result = pure_draft_splice(app->stored_values, 0, size, (PureSpan){encoded, length}); - if (result != PURE_OK) { pure_draft_hold(app->stored_values, false); return result; } - states[count] = UINT32_MAX; - drafts[count++] = app->stored_values; - } - } - /* The links, written whole when they changed. */ - PureVersion links_before = {0, 0}; - bool links_written = false; - if (app->links_changed) { - PureResult result = app->stored_links ? PURE_OK : open_state(app, "", "links", &app->stored_links); - size_t length; - unsigned char *encoded = result == PURE_OK ? encode_links(app, &length) : NULL; - if (result == PURE_OK && !encoded) result = PURE_ALLOCATION; - if (result == PURE_OK) { - links_before = pure_draft_version(app->stored_links); - pure_draft_hold(app->stored_links, true); - result = pure_draft_splice(app->stored_links, 0, pure_draft_size(app->stored_links), (PureSpan){encoded, length}); - if (result != PURE_OK) pure_draft_hold(app->stored_links, false); - } - free(encoded); - if (result != PURE_OK) { - if (values_changed) { - pure_draft_restore(app->stored_values, values_before); - pure_draft_hold(app->stored_values, false); - } - return result; - } - links_written = true; - states[count] = UINT32_MAX; - drafts[count++] = app->stored_links; - } - if (!count && !document_count) return PURE_OK; - PureResult result = app->data.save(app->data.context, documents, document_count, drafts, count, revisions); - for (size_t k = 0; result == PURE_OK && k < count; ++k) - if (states[k] != UINT32_MAX) app->saved[states[k]] = pure_draft_version(drafts[k]); - if (values_changed) { - if (result != PURE_OK) pure_draft_restore(app->stored_values, values_before); - pure_draft_hold(app->stored_values, false); - } - if (links_written) { - if (result != PURE_OK) pure_draft_restore(app->stored_links, links_before); - pure_draft_hold(app->stored_links, false); - } - return result; -} |
