pfd[0].fd = 0;
pfd[0].events = POLLIN;
- return poll(pfd, 1, hund*10) > 0;
+ return safe_poll(pfd, 1, hund*10) > 0;
}
#define readbuffer bb_common_bufsiz1
pfd[0].events = POLLIN;
// Wait 50 ms
// keep reading while there are input chars and room in buffer
- while (poll(pfd, 1, 50) > 0 && n <= (MAX_LINELEN - 5)) {
+ while (safe_poll(pfd, 1, 50) > 0 && n <= (MAX_LINELEN - 5)) {
// read the rest of the ESC string
int r = read(0, readbuffer + n, MAX_LINELEN - n);
if (r > 0)
/* "Opens" stdin if filename is special, else just opens file: */
extern FILE *fopen_or_warn_stdin(const char *filename);
+/* Wrapper which restarts poll on EINTR or ENOMEM.
+ * On other errors complains [perror("poll")] and returns.
+ * Warning! May take (much) longer than timeout_ms to return!
+ * If this is a problem, use bare poll and open-code EINTR/ENOMEM handling */
+int safe_poll(struct pollfd *ufds, nfds_t nfds, int timeout_ms);
+
/* Convert each alpha char in str to lower-case */
-extern char* str_tolower(char *str);
+char* str_tolower(char *str);
char *utoa(unsigned n);
char *itoa(int n);
lib-y += remove_file.o
lib-y += restricted_shell.o
lib-y += run_shell.o
+lib-y += safe_poll.o
lib-y += safe_strncpy.o
lib-y += safe_write.o
lib-y += setup_environment.o
--- /dev/null
+/* vi: set sw=4 ts=4: */
+/*
+ * Utility routines.
+ *
+ * Copyright (C) 2007 by Denys Vlasenko <vda.linux@googlemail.com>
+ *
+ * Licensed under GPLv2, see file LICENSE in this tarball for details.
+ */
+
+#include "libbb.h"
+
+/* Wrapper which restarts poll on EINTR or ENOMEM.
+ * On other errors does perror("poll") and returns.
+ * Warning! May take longer than timeout_ms to return! */
+int safe_poll(struct pollfd *ufds, nfds_t nfds, int timeout)
+{
+ while (1) {
+ int n = poll(ufds, nfds, timeout);
+ if (n >= 0)
+ return n;
+ /* Make sure we inch towards completion */
+ if (timeout > 0)
+ timeout--;
+ /* E.g. strace causes poll to return this */
+ if (errno == EINTR)
+ continue;
+ /* Kernel is very low on memory. Retry. */
+ /* I doubt many callers would handle this correctly! */
+ if (errno == ENOMEM)
+ continue;
+ bb_perror_msg("poll");
+ return n;
+ }
+}
#include "libbb.h"
/* Like strncpy but make sure the resulting string is always 0 terminated. */
-char * safe_strncpy(char *dst, const char *src, size_t size)
+char *safe_strncpy(char *dst, const char *src, size_t size)
{
if (!size) return dst;
dst[--size] = '\0';
pfd[1].events = POLLIN;
while (1) {
int i;
- while (-1 == poll(pfd, 2, -1) && EINTR == errno)
- continue;
+ safe_poll(pfd, 2, -1);
for (i = 0; i < 2; ++i) {
if (pfd[i].revents & POLLIN) {
len = read(pfd[i].fd, bb_common_bufsiz1, COMMON_BUFSIZE);
}
/* Now wait on the set of sockets */
- count = poll(pfd, 3, -1);
+ count = safe_poll(pfd, 3, -1);
if (count <= 0) {
-#if 0
- if (errno == EINTR)
- continue;
-#endif
#if 0
if (waitpid(pid, &status, WNOHANG) <= 0) {
/* Weird. CGI didn't exit and no fd's
/* Receive packet */
/*pfd[0].fd = socketfd;*/
pfd[0].events = POLLIN;
- switch (poll(pfd, 1, waittime_ms)) {
+ switch (safe_poll(pfd, 1, waittime_ms)) {
unsigned from_port;
case 1:
from->len = peer_lsa->len;
goto send_again; /* resend last sent pkt */
default:
- bb_perror_msg("poll");
+ /*bb_perror_msg("poll"); - done in safe_poll */
goto ret;
}
process_pkt:
pfd[0].fd = sock;
pfd[0].events = POLLIN;
- if (poll(pfd, 1, waittime * 1000) > 0)
+ if (safe_poll(pfd, 1, waittime * 1000) > 0)
cc = recvfrom(sock, packet, sizeof(packet), 0,
(struct sockaddr *)fromp, &fromlen);
return cc;
unsigned prevTime = monotonic_us();
pfd[0].events = POLLIN;
- r = poll(pfd, 1, timeout_ms);
+ r = safe_poll(pfd, 1, timeout_ms);
if (r < 0) {
- if (errno != EINTR) {
- bb_perror_msg("poll");
- break;
- }
+ break;
} else if (r) {
if (read(s, &arp, sizeof(arp)) < 0)
break;
VDBG("...wait %d %s nprobes=%u, nclaims=%u\n",
timeout_ms, intf, nprobes, nclaims);
- switch (poll(fds, 1, timeout_ms)) {
+
+ switch (safe_poll(fds, 1, timeout_ms)) {
+
+ default:
+ /*bb_perror_msg("poll"); - done in safe_poll */
+ return EXIT_FAILURE;
// timeout
case 0:
break;
} // switch (state)
break; // case 0 (timeout)
+
// packets arriving
case 1:
// We need to adjust the timeout in case we didn't receive
nclaims = 0;
break;
} // switch state
-
break; // case 1 (packets arriving)
- default:
- why = "poll";
- goto bad;
} // switch poll
- }
+ } // while (1)
bad:
bb_perror_msg("%s, %s", intf, why);
return EXIT_FAILURE;
#if !ENABLE_FEATURE_USE_TERMIOS
sleep(interval);
#else
- if (poll(pfd, 1, interval * 1000) != 0) {
+ if (safe_poll(pfd, 1, interval * 1000) > 0) {
if (read(0, &c, 1) != 1) /* signal */
break;
if (c == initial_settings.c_cc[VINTR])
}
/* Used for reading stdin */
-static int buffer_pread(int fd, char *s, unsigned len)
+static int buffer_pread(/*int fd, */char *s, unsigned len)
{
unsigned now;
struct pollfd input;
poll(&input, 1, i * 1000);
sigprocmask(SIG_BLOCK, blocked_sigset, NULL);
- i = ndelay_read(fd, s, len);
+ i = ndelay_read(0, s, len);
if (i >= 0)
break;
if (errno == EINTR)
if (!np && !exitasap) {
i = linemax - stdin_cnt; /* avail. bytes at tail */
if (i >= 128) {
- i = buffer_pread(0, lineptr + stdin_cnt, i);
+ i = buffer_pread(/*0, */lineptr + stdin_cnt, i);
if (i <= 0) /* EOF or error on stdin */
exitasap = 1;
else {
/* read/write repeatedly until we see it */
while (ch != '\n') {
/* lineptr is emptied now, safe to use as buffer */
- stdin_cnt = exitasap ? -1 : buffer_pread(0, lineptr, linemax);
+ stdin_cnt = exitasap ? -1 : buffer_pread(/*0, */lineptr, linemax);
if (stdin_cnt <= 0) { /* EOF or error on stdin */
exitasap = 1;
lineptr[0] = ch = '\n';