+++ /dev/null
-#include "external-agent.h"
-#include "lock-tracking.h"
-#include "logging.h"
-#include <sys/types.h>
-#include <sys/wait.h>
-#include <unistd.h>
-#include <err.h>
-#include <fcntl.h>
-#include <stdlib.h>
-#include <limits.h>
-#include <string.h>
-#include <errno.h>
-#include <ccan/tdb/tdb.h>
-#include <ccan/tdb/tdb_private.h>
-#include <ccan/tap/tap.h>
-#include <stdio.h>
-#include <stdarg.h>
-
-static struct tdb_context *tdb;
-
-static enum agent_return do_operation(enum operation op, const char *name)
-{
- TDB_DATA k;
- enum agent_return ret;
- TDB_DATA data;
-
- if (op != OPEN && op != OPEN_WITH_CLEAR_IF_FIRST && !tdb) {
- diag("external: No tdb open!");
- return OTHER_FAILURE;
- }
-
- k.dptr = (void *)name;
- k.dsize = strlen(name);
-
- locking_would_block = 0;
- switch (op) {
- case OPEN:
- if (tdb) {
- diag("Already have tdb %s open", tdb_name(tdb));
- return OTHER_FAILURE;
- }
- tdb = tdb_open_ex(name, 0, TDB_DEFAULT, O_RDWR, 0,
- &taplogctx, NULL);
- if (!tdb) {
- if (!locking_would_block)
- diag("Opening tdb gave %s", strerror(errno));
- ret = OTHER_FAILURE;
- } else
- ret = SUCCESS;
- break;
- case OPEN_WITH_CLEAR_IF_FIRST:
- if (tdb)
- return OTHER_FAILURE;
- tdb = tdb_open_ex(name, 0, TDB_CLEAR_IF_FIRST, O_RDWR, 0,
- &taplogctx, NULL);
- ret = tdb ? SUCCESS : OTHER_FAILURE;
- break;
- case TRANSACTION_START:
- ret = tdb_transaction_start(tdb) == 0 ? SUCCESS : OTHER_FAILURE;
- break;
- case FETCH:
- data = tdb_fetch(tdb, k);
- if (data.dptr == NULL) {
- if (tdb_error(tdb) == TDB_ERR_NOEXIST)
- ret = FAILED;
- else
- ret = OTHER_FAILURE;
- } else if (data.dsize != k.dsize
- || memcmp(data.dptr, k.dptr, k.dsize) != 0) {
- ret = OTHER_FAILURE;
- } else {
- ret = SUCCESS;
- }
- free(data.dptr);
- break;
- case STORE:
- ret = tdb_store(tdb, k, k, 0) == 0 ? SUCCESS : OTHER_FAILURE;
- break;
- case TRANSACTION_COMMIT:
- ret = tdb_transaction_commit(tdb)==0 ? SUCCESS : OTHER_FAILURE;
- break;
- case CHECK:
- ret = tdb_check(tdb, NULL, NULL) == 0 ? SUCCESS : OTHER_FAILURE;
- break;
- case NEEDS_RECOVERY:
- ret = tdb_needs_recovery(tdb) ? SUCCESS : FAILED;
- break;
- case CLOSE:
- ret = tdb_close(tdb) == 0 ? SUCCESS : OTHER_FAILURE;
- tdb = NULL;
- break;
- default:
- ret = OTHER_FAILURE;
- }
-
- if (locking_would_block)
- ret = WOULD_HAVE_BLOCKED;
-
- return ret;
-}
-
-struct agent {
- int cmdfd, responsefd;
-};
-
-/* Do this before doing any tdb stuff. Return handle, or NULL. */
-struct agent *prepare_external_agent(void)
-{
- int pid, ret;
- int command[2], response[2];
- char name[1+PATH_MAX];
-
- if (pipe(command) != 0 || pipe(response) != 0)
- return NULL;
-
- pid = fork();
- if (pid < 0)
- return NULL;
-
- if (pid != 0) {
- struct agent *agent = malloc(sizeof(*agent));
-
- close(command[0]);
- close(response[1]);
- agent->cmdfd = command[1];
- agent->responsefd = response[0];
- return agent;
- }
-
- close(command[1]);
- close(response[0]);
-
- /* We want to fail, not block. */
- nonblocking_locks = true;
- log_prefix = "external: ";
- while ((ret = read(command[0], name, sizeof(name))) > 0) {
- enum agent_return result;
-
- result = do_operation(name[0], name+1);
- if (write(response[1], &result, sizeof(result))
- != sizeof(result))
- err(1, "Writing response");
- }
- exit(0);
-}
-
-/* Ask the external agent to try to do an operation. */
-enum agent_return external_agent_operation(struct agent *agent,
- enum operation op,
- const char *name)
-{
- enum agent_return res;
- unsigned int len;
- char *string;
-
- if (!name)
- name = "";
- len = 1 + strlen(name) + 1;
- string = malloc(len);
-
- string[0] = op;
- strcpy(string+1, name);
-
- if (write(agent->cmdfd, string, len) != len
- || read(agent->responsefd, &res, sizeof(res)) != sizeof(res))
- res = AGENT_DIED;
-
- free(string);
- return res;
-}
-
-const char *agent_return_name(enum agent_return ret)
-{
- return ret == SUCCESS ? "SUCCESS"
- : ret == WOULD_HAVE_BLOCKED ? "WOULD_HAVE_BLOCKED"
- : ret == AGENT_DIED ? "AGENT_DIED"
- : ret == FAILED ? "FAILED"
- : ret == OTHER_FAILURE ? "OTHER_FAILURE"
- : "**INVALID**";
-}
-
-const char *operation_name(enum operation op)
-{
- switch (op) {
- case OPEN: return "OPEN";
- case OPEN_WITH_CLEAR_IF_FIRST: return "OPEN_WITH_CLEAR_IF_FIRST";
- case TRANSACTION_START: return "TRANSACTION_START";
- case FETCH: return "FETCH";
- case STORE: return "STORE";
- case TRANSACTION_COMMIT: return "TRANSACTION_COMMIT";
- case CHECK: return "CHECK";
- case NEEDS_RECOVERY: return "NEEDS_RECOVERY";
- case CLOSE: return "CLOSE";
- }
- return "**INVALID**";
-}