147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org/* 247be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org * Copyright 2004 The WebRTC Project Authors. All rights reserved. 347be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org * 447be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org * Use of this source code is governed by a BSD-style license 547be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org * that can be found in the LICENSE file in the root of the source 647be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org * tree. An additional intellectual property rights grant can be found 747be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org * in the file PATENTS. All contributing project authors may 847be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org * be found in the AUTHORS file in the root of the source tree. 947be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org */ 1047be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org 1147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org#include <sys/types.h> 1247be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org#include <dirent.h> 1347be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org#include <errno.h> 1447be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org#include <stdlib.h> 1547be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org#include <string.h> 1647be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org 1747be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org#include "webrtc/base/linuxfdwalk.h" 1847be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org 1947be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org// Parses a file descriptor number in base 10, requiring the strict format used 2047be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org// in /proc/*/fd. Returns the value, or -1 if not a valid string. 2147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.orgstatic int parse_fd(const char *s) { 2247be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (!*s) { 2347be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org // Empty string is invalid. 2447be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org return -1; 2547be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 2647be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org int val = 0; 2747be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org do { 2847be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (*s < '0' || *s > '9') { 2947be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org // Non-numeric characters anywhere are invalid. 3047be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org return -1; 3147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 3247be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org int digit = *s++ - '0'; 3347be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org val = val * 10 + digit; 3447be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } while (*s); 3547be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org return val; 3647be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org} 3747be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org 3847be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.orgint fdwalk(void (*func)(void *, int), void *opaque) { 3947be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org DIR *dir = opendir("/proc/self/fd"); 4047be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (!dir) { 4147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org return -1; 4247be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 4347be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org int opendirfd = dirfd(dir); 4447be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org int parse_errors = 0; 4547be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org struct dirent *ent; 4647be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org // Have to clear errno to distinguish readdir() completion from failure. 4747be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org while (errno = 0, (ent = readdir(dir)) != NULL) { 4847be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (strcmp(ent->d_name, ".") == 0 || 4947be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org strcmp(ent->d_name, "..") == 0) { 5047be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org continue; 5147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 5247be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org // We avoid atoi or strtol because those are part of libc and they involve 5347be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org // locale stuff, which is probably not safe from a post-fork context in a 5447be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org // multi-threaded app. 5547be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org int fd = parse_fd(ent->d_name); 5647be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (fd < 0) { 5747be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org parse_errors = 1; 5847be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org continue; 5947be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 6047be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (fd != opendirfd) { 6147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org (*func)(opaque, fd); 6247be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 6347be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 6447be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org int saved_errno = errno; 6547be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (closedir(dir) < 0) { 6647be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (!saved_errno) { 6747be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org // Return the closedir error. 6847be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org return -1; 6947be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 7047be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org // Else ignore it because we have a more relevant error to return. 7147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 7247be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org if (saved_errno) { 7347be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org errno = saved_errno; 7447be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org return -1; 7547be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } else if (parse_errors) { 7647be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org errno = EBADF; 7747be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org return -1; 7847be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } else { 7947be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org return 0; 8047be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org } 8147be73b8629244d6bb63a28198f97f040ce53d21henrike@webrtc.org} 82