webrtc/talk/base/linuxfdwalk.c
henrike@webrtc.org 28e2075280 Adds trunk/talk folder of revision 359 from libjingles google code to
trunk/talk


git-svn-id: http://webrtc.googlecode.com/svn/trunk@4318 4adac7df-926f-26a2-2b94-8c16560cd09d
2013-07-10 00:45:36 +00:00

99 lines
3.1 KiB
C

/*
* libjingle
* Copyright 2004--2009, Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/types.h>
#include <dirent.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include "talk/base/linuxfdwalk.h"
// Parses a file descriptor number in base 10, requiring the strict format used
// in /proc/*/fd. Returns the value, or -1 if not a valid string.
static int parse_fd(const char *s) {
if (!*s) {
// Empty string is invalid.
return -1;
}
int val = 0;
do {
if (*s < '0' || *s > '9') {
// Non-numeric characters anywhere are invalid.
return -1;
}
int digit = *s++ - '0';
val = val * 10 + digit;
} while (*s);
return val;
}
int fdwalk(void (*func)(void *, int), void *opaque) {
DIR *dir = opendir("/proc/self/fd");
if (!dir) {
return -1;
}
int opendirfd = dirfd(dir);
int parse_errors = 0;
struct dirent *ent;
// Have to clear errno to distinguish readdir() completion from failure.
while (errno = 0, (ent = readdir(dir)) != NULL) {
if (strcmp(ent->d_name, ".") == 0 ||
strcmp(ent->d_name, "..") == 0) {
continue;
}
// We avoid atoi or strtol because those are part of libc and they involve
// locale stuff, which is probably not safe from a post-fork context in a
// multi-threaded app.
int fd = parse_fd(ent->d_name);
if (fd < 0) {
parse_errors = 1;
continue;
}
if (fd != opendirfd) {
(*func)(opaque, fd);
}
}
int saved_errno = errno;
if (closedir(dir) < 0) {
if (!saved_errno) {
// Return the closedir error.
return -1;
}
// Else ignore it because we have a more relevant error to return.
}
if (saved_errno) {
errno = saved_errno;
return -1;
} else if (parse_errors) {
errno = EBADF;
return -1;
} else {
return 0;
}
}