calog/libs/calogKv.c
2026-07-03 02:13:23 -05:00

286 lines
9.6 KiB
C

// calogKv.c -- calog key-value library (see calogKv.h). A process-wide, mutex-guarded array
// of {key bytes, key length, value}. kvSet/kvGet/kvHas/kvDelete/kvKeys are natives over that
// shared store; every stored value is a deep copy, so the store owns pure data.
//
// The registry state is STATIC (not heap) and its bookkeeping is never freed: the five
// natives stay reachable (via any context) right up until calogDestroy tears the broker
// registry down, so freeing the state in calogKvShutdown -- which the contract requires
// BEFORE calogDestroy -- would leave those natives dereferencing freed memory. Shutdown
// instead just frees the stored keys + values and empties the array; the small static
// bookkeeping persists for the process (no per-cycle leak), and a post-shutdown native call
// simply sees an empty store.
//
// Function values are refused (calogErrUnsupportedE): storing a CalogFnT would drag script
// callable lifecycle into a data store, so kv sidesteps it entirely and holds data only.
#define _POSIX_C_SOURCE 200809L
#include "calogKv.h"
#include <pthread.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#define KV_INITIAL_CAP 8
#define KV_GROWTH 2
typedef struct KvEntryT {
char *keyBytes;
int64_t keyLen;
CalogValueT value;
} KvEntryT;
// The store (heap array), guarded by gMapMutex. refCount (guarded by gInitMutex) counts
// registered runtimes so the LAST calogKvShutdown frees the store's contents.
static pthread_mutex_t gMapMutex = PTHREAD_MUTEX_INITIALIZER;
static KvEntryT *gEntries = NULL;
static int32_t gCount = 0;
static int32_t gCap = 0;
static pthread_mutex_t gInitMutex = PTHREAD_MUTEX_INITIALIZER;
static int32_t gRefCount = 0;
static bool kvContainsFn(const CalogValueT *value, int32_t depth);
static int32_t kvDelete(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t kvFindLocked(const char *bytes, int64_t length);
static int32_t kvGet(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t kvHas(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t kvKeys(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
static int32_t kvSet(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData);
int32_t calogKvRegister(CalogT *calog) {
pthread_mutex_lock(&gInitMutex);
gRefCount++;
pthread_mutex_unlock(&gInitMutex);
calogRegisterInline(calog, "kvSet", kvSet, NULL);
calogRegisterInline(calog, "kvGet", kvGet, NULL);
calogRegisterInline(calog, "kvHas", kvHas, NULL);
calogRegisterInline(calog, "kvDelete", kvDelete, NULL);
calogRegisterInline(calog, "kvKeys", kvKeys, NULL);
return calogOkE;
}
void calogKvShutdown(void) {
pthread_mutex_lock(&gInitMutex);
if (gRefCount > 0) {
gRefCount--;
}
if (gRefCount <= 0) {
int32_t index;
pthread_mutex_lock(&gMapMutex);
for (index = 0; index < gCount; index++) {
free(gEntries[index].keyBytes);
calogValueFree(&gEntries[index].value);
}
free(gEntries);
gEntries = NULL;
gCount = 0;
gCap = 0;
pthread_mutex_unlock(&gMapMutex);
}
pthread_mutex_unlock(&gInitMutex);
}
static bool kvContainsFn(const CalogValueT *value, int32_t depth) {
int64_t index;
// kv stores only data (copied by value); a function value -- at the top level OR nested in
// an aggregate -- would retain a CalogFnT into the process-wide store past its owner's life,
// so reject any value that carries one. Too-deep is rejected as unverifiable.
if (depth >= CALOG_MAX_DEPTH) {
return true;
}
if (value->type == calogFnE) {
return true;
}
if (value->type == calogAggE) {
for (index = 0; index < value->as.agg->arrayCount; index++) {
if (kvContainsFn(&value->as.agg->array[index], depth + 1)) {
return true;
}
}
for (index = 0; index < value->as.agg->pairCount; index++) {
if (kvContainsFn(&value->as.agg->pairs[index].key, depth + 1)) {
return true;
}
if (kvContainsFn(&value->as.agg->pairs[index].value, depth + 1)) {
return true;
}
}
}
return false;
}
static int32_t kvDelete(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
int32_t index;
(void)userData;
calogValueNil(result);
if (argCount != 1 || args[0].type != calogStringE) {
return calogFail(result, calogErrArgE, "kvDelete expects (key)");
}
pthread_mutex_lock(&gMapMutex);
index = kvFindLocked(args[0].as.s.bytes, args[0].as.s.length);
if (index >= 0) {
free(gEntries[index].keyBytes);
calogValueFree(&gEntries[index].value);
gEntries[index] = gEntries[gCount - 1];
gCount--;
}
pthread_mutex_unlock(&gMapMutex);
return calogOkE;
}
static int32_t kvFindLocked(const char *bytes, int64_t length) {
int32_t index;
for (index = 0; index < gCount; index++) {
if (gEntries[index].keyLen == length && memcmp(gEntries[index].keyBytes, bytes, (size_t)length) == 0) {
return index;
}
}
return -1;
}
static int32_t kvGet(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
int32_t index;
int32_t status;
(void)userData;
calogValueNil(result);
if (argCount != 1 || args[0].type != calogStringE) {
return calogFail(result, calogErrArgE, "kvGet expects (key)");
}
status = calogOkE;
pthread_mutex_lock(&gMapMutex);
index = kvFindLocked(args[0].as.s.bytes, args[0].as.s.length);
if (index >= 0) {
status = calogValueCopy(result, &gEntries[index].value);
}
pthread_mutex_unlock(&gMapMutex);
if (status != calogOkE) {
calogValueFree(result);
return calogFail(result, status, "kvGet: out of memory");
}
return calogOkE;
}
static int32_t kvHas(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
int32_t index;
(void)userData;
calogValueNil(result);
if (argCount != 1 || args[0].type != calogStringE) {
return calogFail(result, calogErrArgE, "kvHas expects (key)");
}
pthread_mutex_lock(&gMapMutex);
index = kvFindLocked(args[0].as.s.bytes, args[0].as.s.length);
pthread_mutex_unlock(&gMapMutex);
calogValueBool(result, index >= 0);
return calogOkE;
}
static int32_t kvKeys(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
CalogAggT *agg;
int32_t index;
int32_t status;
(void)args;
(void)argCount;
(void)userData;
calogValueNil(result);
status = calogAggCreate(&agg, calogListE);
if (status != calogOkE) {
return calogFail(result, status, "kvKeys: out of memory");
}
pthread_mutex_lock(&gMapMutex);
for (index = 0; index < gCount; index++) {
CalogValueT key;
status = calogValueString(&key, gEntries[index].keyBytes, gEntries[index].keyLen);
if (status != calogOkE) {
break;
}
status = calogAggPush(agg, &key);
if (status != calogOkE) {
calogValueFree(&key);
break;
}
}
pthread_mutex_unlock(&gMapMutex);
if (status != calogOkE) {
calogAggFree(agg);
return calogFail(result, status, "kvKeys: out of memory");
}
calogValueAgg(result, agg);
return calogOkE;
}
static int32_t kvSet(CalogValueT *args, int32_t argCount, CalogValueT *result, void *userData) {
CalogValueT copy;
char *keyBytes;
int64_t keyLen;
int32_t index;
int32_t status;
(void)userData;
calogValueNil(result);
if (argCount != 2 || args[0].type != calogStringE) {
return calogFail(result, calogErrArgE, "kvSet expects (key, value)");
}
if (kvContainsFn(&args[1], 0)) {
return calogFail(result, calogErrUnsupportedE, "kv stores data, not functions");
}
status = calogValueCopy(&copy, &args[1]);
if (status != calogOkE) {
calogValueFree(&copy);
return calogFail(result, status, "kvSet: out of memory");
}
keyLen = args[0].as.s.length;
pthread_mutex_lock(&gMapMutex);
index = kvFindLocked(args[0].as.s.bytes, keyLen);
if (index >= 0) {
// Replace: drop the old value, keep the existing key bytes.
calogValueFree(&gEntries[index].value);
gEntries[index].value = copy;
pthread_mutex_unlock(&gMapMutex);
return calogOkE;
}
if (gCount == gCap) {
int32_t newCap;
KvEntryT *grown;
newCap = (gCap == 0) ? KV_INITIAL_CAP : gCap * KV_GROWTH;
grown = (KvEntryT *)realloc(gEntries, (size_t)newCap * sizeof(KvEntryT));
if (grown == NULL) {
pthread_mutex_unlock(&gMapMutex);
calogValueFree(&copy);
return calogFail(result, calogErrOomE, "kvSet: out of memory");
}
gEntries = grown;
gCap = newCap;
}
keyBytes = (char *)malloc((size_t)keyLen + 1);
if (keyBytes == NULL) {
pthread_mutex_unlock(&gMapMutex);
calogValueFree(&copy);
return calogFail(result, calogErrOomE, "kvSet: out of memory");
}
if (keyLen > 0) {
memcpy(keyBytes, args[0].as.s.bytes, (size_t)keyLen);
}
keyBytes[keyLen] = '\0';
gEntries[gCount].keyBytes = keyBytes;
gEntries[gCount].keyLen = keyLen;
gEntries[gCount].value = copy;
gCount++;
pthread_mutex_unlock(&gMapMutex);
return calogOkE;
}