1 /* 2 * Copyright (C) 2015 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include "log.h" 18 19 #include <stdlib.h> 20 #include <string.h> 21 #include <sys/uio.h> 22 23 #include <selinux/selinux.h> 24 25 #include <android-base/stringprintf.h> 26 27 static void init_klog_vwrite(int level, const char* fmt, va_list ap) { 28 static const char* tag = basename(getprogname()); 29 30 if (level > klog_get_level()) return; 31 32 // The kernel's printk buffer is only 1024 bytes. 33 // TODO: should we automatically break up long lines into multiple lines? 34 // Or we could log but with something like "..." at the end? 35 char buf[1024]; 36 size_t prefix_size = snprintf(buf, sizeof(buf), "<%d>%s: ", level, tag); 37 size_t msg_size = vsnprintf(buf + prefix_size, sizeof(buf) - prefix_size, fmt, ap); 38 if (msg_size >= sizeof(buf) - prefix_size) { 39 msg_size = snprintf(buf + prefix_size, sizeof(buf) - prefix_size, 40 "(%zu-byte message too long for printk)\n", msg_size); 41 } 42 43 iovec iov[1]; 44 iov[0].iov_base = buf; 45 iov[0].iov_len = prefix_size + msg_size; 46 47 klog_writev(level, iov, 1); 48 } 49 50 void init_klog_write(int level, const char* fmt, ...) { 51 va_list ap; 52 va_start(ap, fmt); 53 init_klog_vwrite(level, fmt, ap); 54 va_end(ap); 55 } 56 57 int selinux_klog_callback(int type, const char *fmt, ...) { 58 int level = KLOG_ERROR_LEVEL; 59 if (type == SELINUX_WARNING) { 60 level = KLOG_WARNING_LEVEL; 61 } else if (type == SELINUX_INFO) { 62 level = KLOG_INFO_LEVEL; 63 } 64 va_list ap; 65 va_start(ap, fmt); 66 init_klog_vwrite(level, fmt, ap); 67 va_end(ap); 68 return 0; 69 } 70
