blob: b60622e84f53c190069d953e8395d40e3b923aa5 [file] [log] [blame]
/*
* File: EINTR_wrappers.c
*
* This file implements the wrapper functions for some of the System APIs
*
* Copyright (C) <2019> <American Megatrends International LLC>
*
*/
#include "EINTR_wrappers.h"
#if defined(__linux__)
#include <sys/msg.h>
#include <sys/file.h>
#endif
#include <errno.h>
#include <unistd.h>
static const int OneSecondasNS = 1000000000;
#ifndef bool
typedef int bool;
#endif
#ifndef TRUE
#define TRUE (1)
#endif
#ifndef FALSE
#define FALSE (0)
#endif
typedef struct
{
bool OnePoll;
struct timespec EndTime, Timeout;
} SIGWRAP_TIMEOUT;
static void sigwrap_InitTimeout(SIGWRAP_TIMEOUT *pDst, const struct timespec *timeout)
{
pDst->Timeout = *timeout;
if ((timeout->tv_sec == 0) && (timeout->tv_nsec == 0)) // If both value are zero than only a single poll is requested!
{
pDst->OnePoll = 1;
return;
}
pDst->OnePoll = 0;
struct timespec Now;
(void)clock_gettime(CLOCK_MONOTONIC_RAW, &Now); // CLOCK_MONOTONIC_RAW is not affected by NTP etc.
pDst->EndTime.tv_sec = Now.tv_sec + pDst->Timeout.tv_sec; // Check necessary in 2038 due to signed integer variables
pDst->EndTime.tv_nsec = Now.tv_nsec + pDst->Timeout.tv_nsec;
if (pDst->EndTime.tv_nsec >= OneSecondasNS)
{
pDst->EndTime.tv_sec += (pDst->EndTime.tv_nsec / OneSecondasNS);
pDst->EndTime.tv_nsec = (pDst->EndTime.tv_nsec % OneSecondasNS);
}
}
static bool sigwrap_CheckTimeout(SIGWRAP_TIMEOUT *pTo)
{
if (pTo->OnePoll == TRUE) // Make sure, that in the case that a single poll is requested at least one call is not terminated with EINTR
return FALSE;
struct timespec Now;
(void)clock_gettime(CLOCK_MONOTONIC_RAW, &Now);
if (Now.tv_sec > pTo->EndTime.tv_sec) // Can become a problem already in 2038 due to signed integer variables
return TRUE;
pTo->Timeout.tv_nsec = pTo->EndTime.tv_nsec - Now.tv_nsec;
pTo->Timeout.tv_sec = pTo->EndTime.tv_sec - Now.tv_sec;
if (pTo->Timeout.tv_sec == 0)
{
if (pTo->Timeout.tv_nsec <= 0)
return TRUE;
}
else if (pTo->Timeout.tv_nsec < 0)
{
pTo->Timeout.tv_nsec += OneSecondasNS;
pTo->Timeout.tv_sec--;
}
return FALSE;
}
int sigwrap_semop(int semid, struct sembuf *sops, size_t nsops)
{
while (1)
{
if (semop(semid, sops, nsops) == 0)
return 0;
if (errno != EINTR)
return -1;
}
}
#if 0
int sigwrap_semtimedop(int semid, struct sembuf *sops, size_t nsops, const struct timespec *timeout)
{
SIGWRAP_TIMEOUT To;
if (timeout == NULL)
return (sigwrap_semop(semid, sops, nsops));
sigwrap_InitTimeout(&To, timeout);
while (1)
{
if (semtimedop(semid, sops, nsops, &To.Timeout) == 0)
return 0;
if (errno != EINTR)
return -1;
if (sigwrap_CheckTimeout(&To))
{
errno = EAGAIN;
return -1;
}
}
}
#endif
int sigwrap_epoll_wait(int epfd, struct epoll_event *events, int maxevents, int timeout)
{
SIGWRAP_TIMEOUT To;
if (timeout != -1)
{
struct timespec Timeout;
Timeout.tv_sec = timeout / 1000;
Timeout.tv_nsec = (timeout % 1000) * 1000000; // Convert msec to nsec
sigwrap_InitTimeout(&To, &Timeout);
}
while (1)
{
int Result = epoll_wait(epfd, events, maxevents, timeout);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
if (timeout == -1)
continue;
if (sigwrap_CheckTimeout(&To))
return 0;
timeout = To.Timeout.tv_sec * 1000 + To.Timeout.tv_nsec / 1000000;
}
}
int sigwrap_epoll_pwait(int epfd, struct epoll_event *events, int maxevents, int timeout, const sigset_t *sigmask)
{
SIGWRAP_TIMEOUT To;
if (timeout != -1)
{
struct timespec Timeout;
Timeout.tv_sec = timeout / 1000;
Timeout.tv_nsec = (timeout % 1000) * 1000000; // Convert msec to nsec
sigwrap_InitTimeout(&To, &Timeout);
}
while (1)
{
int Result = epoll_pwait(epfd, events, maxevents, timeout, sigmask);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
if (timeout == -1)
continue;
if (sigwrap_CheckTimeout(&To))
return 0;
timeout = To.Timeout.tv_sec * 1000 + To.Timeout.tv_nsec / 1000000;
}
}
int sigwrap_sigwaitinfo(const sigset_t *set, siginfo_t *info)
{
while (1)
{
int Result = sigwaitinfo(set, info);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
int sigwrap_sigtimedwait(const sigset_t *set, siginfo_t *info, const struct timespec *timeout)
{
SIGWRAP_TIMEOUT To;
sigwrap_InitTimeout(&To, timeout);
while (1)
{
int Result = sigtimedwait(set, info, &To.Timeout);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
if (sigwrap_CheckTimeout(&To))
return 0;
}
}
int sigwrap_nanosleep(const struct timespec *req, struct timespec *rem)
{
struct timespec Wait, Remain;
if (!rem)
rem = &Remain;
Wait = *req;
while (1)
{
if (nanosleep(&Wait, rem) == 0)
return 0;
if (errno != EINTR)
return -1;
Wait = *rem;
}
}
int sigwrap_clock_nanosleep(clockid_t clock_id, int flags, const struct timespec *request, struct timespec *remain)
{
struct timespec Wait, Remain;
if (!remain)
remain = &Remain;
Wait = *request;
while (1)
{
int Result = clock_nanosleep(clock_id, flags, &Wait, remain);
if (Result == 0)
return Result;
if (Result != EINTR)
return Result;
if (flags != TIMER_ABSTIME)
Wait = *remain;
}
}
int sigwrap_usleep(useconds_t usec)
{
SIGWRAP_TIMEOUT To;
struct timespec Timeout;
Timeout.tv_sec = usec / 1000000;
Timeout.tv_nsec = (usec % 1000000) * 1000;
sigwrap_InitTimeout(&To, &Timeout);
while (1)
{
if (usleep(usec) == 0)
return 0;
if (errno != EINTR)
return -1;
if (sigwrap_CheckTimeout(&To))
return 0;
usec = To.Timeout.tv_sec * 1000000 + To.Timeout.tv_nsec / 1000;
}
}
int sigwrap_poll(struct pollfd *fds, nfds_t nfds, int timeout)
{
SIGWRAP_TIMEOUT To;
if (timeout > 0)
{
struct timespec Timeout;
Timeout.tv_sec = timeout / 1000;
Timeout.tv_nsec = (timeout % 1000) * 1000000;
sigwrap_InitTimeout(&To, &Timeout);
}
while (1)
{
int Result = poll(fds, nfds, timeout);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
if (timeout < 0) // Specifying a negative value in timeout means an infinite/no timeout.
continue;
else if (timeout == 0)
continue; // We want to make sure that at least one check was not aborted with EINTR
if (sigwrap_CheckTimeout(&To))
return 0;
timeout = To.Timeout.tv_sec * 1000 + To.Timeout.tv_nsec / 1000000;
}
}
#if 0
int sigwrap_ppoll(struct pollfd *fds, nfds_t nfds, const struct timespec *tmo_p, const sigset_t *sigmask)
{
SIGWRAP_TIMEOUT To;
if (tmo_p != NULL)
{
sigwrap_InitTimeout(&To, tmo_p);
tmo_p = &To.Timeout;
}
while (1)
{
int Result = ppoll(fds, nfds, tmo_p, sigmask);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
if (tmo_p == NULL)
continue;
if (sigwrap_CheckTimeout(&To))
return 0;
}
}
#endif
int sigwrap_select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, struct timeval *timeout)
{
while (1)
{
int Result = select(nfds, readfds, writefds, exceptfds, timeout);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
int sigwrap_pselect(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds, const struct timespec *timeout,
const sigset_t *sigmask)
{
SIGWRAP_TIMEOUT To;
if (timeout != NULL)
{
sigwrap_InitTimeout(&To, timeout);
timeout = &To.Timeout;
}
while (1)
{
int Result = pselect(nfds, readfds, writefds, exceptfds, timeout, sigmask);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
if (timeout == NULL)
continue;
if (sigwrap_CheckTimeout(&To))
return 0;
}
}
int sigwrap_msgsnd(int msqid, const void *msgp, size_t msgsz, int msgflg)
{
while (1)
{
int Result = msgsnd(msqid, msgp, msgsz, msgflg);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
ssize_t sigwrap_msgrcv(int msqid, void *msgp, size_t msgsz, long msgtyp, int msgflg)
{
while (1)
{
ssize_t Result = msgrcv(msqid, msgp, msgsz, msgtyp, msgflg);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
int sigwrap_connect(int sockfd, const struct sockaddr *addr, socklen_t addrlen)
{
while (1)
{
int Result = connect(sockfd, addr, addrlen);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
ssize_t sigwrap_send(int sockfd, const void *buf, size_t len, int flags)
{
while (1)
{
ssize_t Result = send(sockfd, buf, len, flags);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
ssize_t sigwrap_sendto(int sockfd, const void *buf, size_t len, int flags, const struct sockaddr *dest_addr,
socklen_t addrlen)
{
while (1)
{
ssize_t Result = sendto(sockfd, buf, len, flags, dest_addr, addrlen);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
ssize_t sigwrap_sendsendmsg(int sockfd, const struct msghdr *msg, int flags)
{
while (1)
{
ssize_t Result = sendmsg(sockfd, msg, flags);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
int sigwrap_accept(int sockfd, struct sockaddr *addr, socklen_t *addrlen)
{
while (1)
{
int Result = accept(sockfd, addr, addrlen);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
#if 0
int sigwrap_accept4(int sockfd, struct sockaddr *addr, socklen_t *addrlen, int flags)
{
while (1)
{
int Result = accept4(sockfd, addr, addrlen, flags);
if (Result != -1)
return Result;
if (errno != EINTR)
return Result;
}
}
#endif
// EINTR wrapper for the standard read() function. Can be used for sockets that are the to non-blocking mode.
// The length of the returned data can be shorter than the requested one!
ssize_t sigwrap_read(int fd, void *buf, size_t count)
{
while (1)
{
ssize_t Result = read(fd, buf, count);
if (Result != -1)
return (Result);
if (errno != EINTR)
return (Result);
}
}
// EINTR wrapper for the standard read() function. Waits until ALL requested data is available. Use the non-blocking version (sigwrap_read)
// for sockets that are set to non-blocking mode or when partial data is okay
// Although the description for the read() function describes it differently, it seems possible that the original function may already return
// even though partial data has already been read. This implementation makes sure that all requested data have been read.
// See the comment in the signal description https://linux.die.net/man/7/signal
//* read(2), readv(2), write(2), writev(2), and ioctl(2) calls on "slow" devices.
//* A "slow" device is one where the I/O call may block for an indefinite time, for example, a terminal, pipe, or socket.
//* (A disk is not a slow device according to this definition.) If an I/O call on a slow device has already transferred
//* some data by the time it is interrupted by a signal handler, then the call will return a success status (normally, the number of bytes transferred).
ssize_t sigwrap_blocking_read(int hFile, void *pData, size_t RdLen)
{
ssize_t Transfered;
ssize_t Len = RdLen;
while ((Transfered = read(hFile, pData, Len)) != Len)
{
if (Transfered == 0) // EOF reached?
return 0;
if (Transfered != -1)
{
pData += Transfered;
Len -= Transfered;
continue;
}
if (errno != EINTR)
return -1;
}
return RdLen;
}
ssize_t sigwrap_readv(int fd, const struct iovec *iov, int iovcnt)
{
while (1)
{
ssize_t Result = readv(fd, iov, iovcnt);
if (Result != -1)
return (Result);
if (errno != EINTR)
return (Result);
}
}
ssize_t sigwrap_recv(int sockfd, void *buf, size_t len, int flags)
{
while (1)
{
ssize_t Result = recv(sockfd, buf, len, flags);
if (Result != -1)
return (Result);
if (errno != EINTR)
return (Result);
}
}
ssize_t sigwrap_recvfrom(int sockfd, void *buf, size_t len, int flags, struct sockaddr *src_addr, socklen_t *addrlen)
{
while (1)
{
ssize_t Result = recvfrom(sockfd, buf, len, flags, src_addr, addrlen);
if (Result != -1)
return (Result);
if (errno != EINTR)
return (Result);
}
}
ssize_t sigwrap_recvmsg(int sockfd, struct msghdr *msg, int flags)
{
while (1)
{
ssize_t Result = recvmsg(sockfd, msg, flags);
if (Result != -1)
return (Result);
if (errno != EINTR)
return (Result);
}
}
// EINTR wrapper for the standard write() function. Can be used for sockets that are the to non-blocking mode.
// The length of the effectively written data can be shorter than the length specified at the function call!
ssize_t sigwrap_write(int fd, const void *buf, size_t count)
{
while (1)
{
ssize_t Result = write(fd, buf, count);
if (Result != -1)
return (Result);
if (errno != EINTR)
return (Result);
}
}
// EINTR wrapper for the standard write() function. Waits until ALL data is written! Use the non-blocking version (sigwrap_write)
// for sockets that are set to non-blocking mode, or when it is OK to write only partial data.
// Although the description for the write() function describes it differently, it seems possible that the original function may already return
// even though partial data has already been written. This implementation makes sure that all requested data have been written.
// See the comment in the signal description https://linux.die.net/man/7/signal
//* read(2), readv(2), write(2), writev(2), and ioctl(2) calls on "slow" devices.
//* A "slow" device is one where the I/O call may block for an indefinite time, for example, a terminal, pipe, or socket.
//* (A disk is not a slow device according to this definition.) If an I/O call on a slow device has already transferred
//* some data by the time it is interrupted by a signal handler, then the call will return a success status (normally, the number of bytes transferred).
ssize_t sigwrap_blocking_write(int hFile, const void *pData, ssize_t WrtLen)
{
ssize_t Written;
ssize_t Len = WrtLen;
while ((Written = write(hFile, pData, Len)) != Len)
{
if (Written != -1)
{
pData += Written;
Len -= Written;
continue;
}
if (errno != EINTR)
return -1;
}
return WrtLen;
}
ssize_t sigwrap_writev(int fd, const struct iovec *iov, int iovcnt)
{
while (1)
{
ssize_t Result = writev(fd, iov, iovcnt);
if (Result != -1)
return (Result);
if (errno != EINTR)
return (Result);
}
}
int sigwrap_close(int hFile)
{
while (close(hFile) == -1)
{
if (errno != EINTR)
return -1;
}
return 0;
}
int sigwrap_open_mode(const char *pathname, int flags, mode_t mode)
{
while (1)
{
int hFile = open(pathname, flags, mode);
if(hFile != -1)
return hFile;
if (errno != EINTR)
return hFile;
}
}
int sigwrap_open(const char *pathname, int flags)
{
while (1)
{
int hFile = open(pathname, flags);
if(hFile != -1)
return hFile;
if (errno != EINTR)
return hFile;
}
}
pid_t sigwrap_wait(int *status)
{
while(1)
{
pid_t Result = wait(status);
if(Result != -1)
return Result;
if(errno != EINTR)
return Result;
}
}
pid_t sigwrap_waitpid(pid_t pid, int *status, int options)
{
while(1)
{
pid_t Result = waitpid(pid, status, options);
if(Result != -1)
return Result;
if(errno != EINTR)
return Result;
}
}
int sigwrap_waitid(idtype_t idtype, id_t id, siginfo_t *infop, int options)
{
while(1)
{
int Result = waitid(idtype, id, infop, options);
if(Result != -1)
return Result;
if(errno != EINTR)
return Result;
}
}
int sigwrap_flock(int fd, int operation)
{
while(1)
{
int Result = flock(fd, operation);
if(Result != -1)
return Result;
if(errno != EINTR)
return Result;
}
}