+static void logfopen_callback(void *handle, int mode)
+{
+ struct LogContext *ctx = (struct LogContext *)handle;
+ char buf[256], *event;
+ struct tm tm;
+ const char *fmode;
+
+ if (mode == 0) {
+ ctx->state = L_ERROR; /* disable logging */
+ } else {
+ fmode = (mode == 1 ? "ab" : "wb");
+ ctx->lgfp = f_open(ctx->currlogfilename, fmode, FALSE);
+ if (ctx->lgfp)
+ ctx->state = L_OPEN;
+ else
+ ctx->state = L_ERROR;
+ }
+
+ if (ctx->state == L_OPEN) {
+ /* Write header line into log file. */
+ tm = ltime();
+ strftime(buf, 24, "%Y.%m.%d %H:%M:%S", &tm);
+ logprintf(ctx, "=~=~=~=~=~=~=~=~=~=~=~= PuTTY log %s"
+ " =~=~=~=~=~=~=~=~=~=~=~=\r\n", buf);
+ }
+
+ event = dupprintf("%s session log (%s mode) to file: %s",
+ ctx->state == L_ERROR ?
+ (mode == 0 ? "Disabled writing" : "Error writing") :
+ (mode == 1 ? "Appending" : "Writing new"),
+ (ctx->logtype == LGTYP_ASCII ? "ASCII" :
+ ctx->logtype == LGTYP_DEBUG ? "raw" :
+ ctx->logtype == LGTYP_PACKETS ? "SSH packets" :
+ ctx->logtype == LGTYP_SSHRAW ? "SSH raw data" :
+ "unknown"),
+ filename_to_str(&ctx->currlogfilename));
+ logevent(ctx->frontend, event);
+ sfree(event);
+
+ /*
+ * Having either succeeded or failed in opening the log file,
+ * we should write any queued data out.
+ */
+ assert(ctx->state != L_OPENING); /* make _sure_ it won't be requeued */
+ while (bufchain_size(&ctx->queue)) {
+ void *data;
+ int len;
+ bufchain_prefix(&ctx->queue, &data, &len);
+ logwrite(ctx, data, len);
+ bufchain_consume(&ctx->queue, len);
+ }
+}
+
+/*
+ * Open the log file. Takes care of detecting an already-existing
+ * file and asking the user whether they want to append, overwrite
+ * or cancel logging.
+ */
+void logfopen(void *handle)
+{
+ struct LogContext *ctx = (struct LogContext *)handle;
+ struct tm tm;
+ int mode;
+
+ /* Prevent repeat calls */
+ if (ctx->state != L_CLOSED)
+ return;
+
+ if (!ctx->logtype)
+ return;
+
+ tm = ltime();
+
+ /* substitute special codes in file name */
+ xlatlognam(&ctx->currlogfilename,
+ *conf_get_filename(ctx->conf, CONF_logfilename),
+ conf_get_str(ctx->conf, CONF_host), &tm);
+
+ ctx->lgfp = f_open(ctx->currlogfilename, "r", FALSE); /* file already present? */
+ if (ctx->lgfp) {
+ int logxfovr = conf_get_int(ctx->conf, CONF_logxfovr);
+ fclose(ctx->lgfp);
+ if (logxfovr != LGXF_ASK) {
+ mode = ((logxfovr == LGXF_OVR) ? 2 : 1);
+ } else
+ mode = askappend(ctx->frontend, ctx->currlogfilename,
+ logfopen_callback, ctx);
+ } else
+ mode = 2; /* create == overwrite */
+
+ if (mode < 0)
+ ctx->state = L_OPENING;
+ else
+ logfopen_callback(ctx, mode); /* open the file */
+}
+
+void logfclose(void *handle)
+{
+ struct LogContext *ctx = (struct LogContext *)handle;
+ if (ctx->lgfp) {
+ fclose(ctx->lgfp);
+ ctx->lgfp = NULL;
+ }
+ ctx->state = L_CLOSED;
+}
+
+/*
+ * Log session traffic.
+ */
+void logtraffic(void *handle, unsigned char c, int logmode)
+{
+ struct LogContext *ctx = (struct LogContext *)handle;
+ if (ctx->logtype > 0) {
+ if (ctx->logtype == logmode)
+ logwrite(ctx, &c, 1);
+ }
+}
+