fix(memory): preserve existing DB when sqlite3_open fails

CHANGELOG.md

@@ -5,6 +5,7 @@ All notable changes to ShellClaw are documented here. Format follows [Keep a Cha
 ## [Unreleased]
 
 ### Fixed
+- `memory_init` no longer deletes an existing SQLite DB when `sqlite3_open` fails (permissions or transient I/O).
 - Anthropic `content` parse fails closed when growing the text buffer or `tool_use` array cannot `realloc`, instead of copying against an inflated cap.
 - HTTP 200 JSON-RPC results with a malformed ASAP envelope no longer double-free the duplicated request id.
 - Inbound ASAP `mcp.tool_call` and `state.query` now hold `agent_lock()` around tool execute and SQLite `g_db` reads, matching `task.request`.

src/core/memory.c

@@ -130,6 +130,13 @@ int memory_init(const char *path)
 	int file_existed = path_exists(path);
 	int recreated = 0;
 	if (sqlite3_open(path, &g_db) != SQLITE_OK) {
+		/* Never delete an existing DB on open failure (permissions, transient I/O). */
+		if (file_existed) {
+			fprintf(stderr, "Error: cannot open existing memory DB at %s: %s\n",
+			        path, g_db ? sqlite3_errmsg(g_db) : "unknown");
+			if (g_db) { sqlite3_close(g_db); g_db = NULL; }
+			return -1;
+		}
 		if (g_db) { sqlite3_close(g_db); g_db = NULL; }
 		remove(path);
 		if (sqlite3_open(path, &g_db) != SQLITE_OK) {

tests/test_memory.c

@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/stat.h>
 
 #include "sqlite3.h"
 
@@ -153,11 +154,48 @@ static int test_gateway_schema_migration_v01(void)
 	return 0;
 }
 
+static int test_existing_db_preserved_on_open_failure(void)
+{
+	const char *path = "/tmp/shellclaw_test_open_fail.db";
+	sqlite3 *probe = NULL;
+	int open_rc;
+	remove(path);
+	ASSERT(memory_init(path) == 0);
+	ASSERT(memory_save("preserve", "important data", NULL) == 0);
+	memory_cleanup();
+	ASSERT(chmod(path, 0000) == 0);
+	open_rc = sqlite3_open(path, &probe);
+	if (probe)
+		sqlite3_close(probe);
+	if (open_rc == SQLITE_OK) {
+		/* Root / DAC override: mode 000 still opens. Do not delete. */
+		(void)chmod(path, 0600);
+		remove(path);
+		return 0;
+	}
+	if (memory_init(path) != -1) {
+		fprintf(stderr, "FAIL: %s:%d memory_init(path) == -1\n", __FILE__, __LINE__);
+		(void)chmod(path, 0600);
+		memory_cleanup();
+		remove(path);
+		return 1;
+	}
+	ASSERT(chmod(path, 0600) == 0);
+	ASSERT(memory_init(path) == 0);
+	char buf[256];
+	ASSERT(memory_recall("important", buf, sizeof(buf), 5) == 0);
+	ASSERT(strstr(buf, "important data") != NULL);
+	memory_cleanup();
+	remove(path);
+	return 0;
+}
+
 int main(void)
 {
 	RUN(test_schema_and_fts5());
 	RUN(test_save_overwrite());
 	RUN(test_corrupted_db_recreated());
+	RUN(test_existing_db_preserved_on_open_failure());
 	RUN(test_session_list());
 	RUN(test_session_crud());
 	RUN(test_gateway_schema_new_db());