diff options
Diffstat (limited to 'WWW/Library/Implementation/HTTCP.c')
| -rw-r--r-- | WWW/Library/Implementation/HTTCP.c | 146 |
1 files changed, 142 insertions, 4 deletions
diff --git a/WWW/Library/Implementation/HTTCP.c b/WWW/Library/Implementation/HTTCP.c index 1a6b2621..fdc6b66a 100644 --- a/WWW/Library/Implementation/HTTCP.c +++ b/WWW/Library/Implementation/HTTCP.c @@ -645,7 +645,7 @@ PUBLIC struct hostent * LYGetHostByName ARGS1( struct _statuses { size_t rehostentlen; int h_length; - int child_errno; /* maybe not very useful */ + int child_errno; /* sometimes useful to pass this on */ int child_h_errno; BOOL h_errno_valid; } statuses; @@ -687,7 +687,7 @@ PUBLIC struct hostent * LYGetHostByName ARGS1( CTRACE(tfp, "LYGetHostByName: Calling gethostbyname(%s)\n", host); #endif /* MVS */ - CTRACE_FLUSH(tfp); /* so child messages will not mess parent log */ + CTRACE_FLUSH(tfp); /* so child messages will not mess up parent log */ lynx_nsl_status = HT_INTERNAL; /* should be set to something else below */ @@ -699,6 +699,10 @@ PUBLIC struct hostent * LYGetHostByName ARGS1( */ { int got_rehostent = 0; +#if HAVE_SIGACTION + sigset_t old_sigset; + sigset_t new_sigset; +#endif /* ** Pipe, child pid, status buffers, start time, select() ** control variables. @@ -727,6 +731,32 @@ PUBLIC struct hostent * LYGetHostByName ARGS1( pipe(pfd); +#if HAVE_SIGACTION + /* + * Attempt to prevent a rare situation where the child + * could execute the Lynx signal handlers because it gets + * killed before it even has a chance to reset its handlers, + * resulting in bogus 'Exiting via interrupt' message and + * screen corruption or worse. + * Should that continue to be reported, for systems without + * sigprocmask(), we need to find a different solutions for + * those. - kw 19990430 + */ + sigemptyset(&new_sigset); + sigaddset(&new_sigset, SIGTERM); + sigaddset(&new_sigset, SIGINT); +#ifndef NOSIGHUP + sigaddset(&new_sigset, SIGHUP); +#endif /* NOSIGHUP */ +#ifdef SIGTSTP + sigaddset(&new_sigset, SIGTSTP); +#endif /* SIGTSTP */ +#ifdef SIGWINCH + sigaddset(&new_sigset, SIGWINCH); +#endif /* SIGWINCH */ + sigprocmask(SIG_BLOCK, &new_sigset, &old_sigset); +#endif /* HAVE_SIGACTION */ + if ((fpid = fork()) == 0 ) { struct hostent *phost; /* Pointer to host - See netdb.h */ /* @@ -764,13 +794,26 @@ PUBLIC struct hostent * LYGetHostByName ARGS1( signal(SIGSEGV, SIG_DFL); signal(SIGILL, SIG_DFL); +#if HAVE_SIGACTION + /* Restore signal mask to whatever it was before the fork. -kw */ + sigprocmask(SIG_SETMASK, &old_sigset, NULL); +#endif /* HAVE_SIGACTION */ + /* ** Child won't use read side. -BL */ close(pfd[0]); +#ifdef HAVE_H_ERRNO + /* to detect cases when it doesn't get set although it should */ + h_errno = -2; +#endif + errno = 0; phost = gethostbyname(host); + statuses.child_errno = errno; statuses.child_h_errno = h_errno; +#ifdef HAVE_H_ERRNO statuses.h_errno_valid = YES; +#endif #ifdef MVS CTRACE(tfp, "LYGetHostByName: gethostbyname() returned %d\n", phost); #endif /* MVS */ @@ -790,12 +833,17 @@ PUBLIC struct hostent * LYGetHostByName ARGS1( statuses.h_length = 0; } else { statuses.h_length = ((struct hostent *)rehostent)->h_length; +#ifdef HAVE_H_ERRNO + if (h_errno == -2) /* success, but h_errno unchanged? */ + statuses.h_errno_valid = NO; +#endif } /* ** Send variables indicating status of lookup to parent. ** That includes rehostentlen, which the parent will use ** as the size for the second read (if > 0). */ + if (!statuses.child_errno) statuses.child_errno = errno; statuses.rehostentlen = rehostentlen; write(pfd[1], &statuses, sizeof(statuses)); @@ -815,6 +863,14 @@ PUBLIC struct hostent * LYGetHostByName ARGS1( } } +#if HAVE_SIGACTION + /* + ** (parent) Restore signal mask to whatever it was + ** before the fork. - kw + */ + sigprocmask(SIG_SETMASK, &old_sigset, NULL); +#endif /* HAVE_SIGACTION */ + /* ** (parent) Wait until lookup finishes, or interrupt, ** or cycled too many times (just in case) -BL @@ -871,8 +927,44 @@ PUBLIC struct hostent * LYGetHostByName ARGS1( if (readret == sizeof(statuses)) { h_errno = statuses.child_h_errno; errno = statuses.child_errno; - if (statuses.h_errno_valid) +#ifdef HAVE_H_ERRNO + if (statuses.h_errno_valid) { lynx_nsl_status = HT_H_ERRNO_VALID; + /* + * If something went wrong in the child process + * other than normal lookup errors, and it appears + * that we have enough info to know what went wrong, + * generate diagnostic output. + * ENOMEM observed on linux in processes constrained + * with ulimit. It would be too unkind to abort + * the session, access to local files or through a + * proxy may still work. - kw + */ + if ( +#ifdef NETDB_INTERNAL /* linux glibc: defined in netdb.h */ + (errno && h_errno == NETDB_INTERNAL) || +#endif + (errno == ENOMEM && + statuses.rehostentlen == 0 && + /* should probably be NETDB_INTERNAL if child + memory exhausted, but we may find that + h_errno remains unchanged. - kw */ + h_errno == -2)) { +#ifndef MULTINET + HTInetStatus("CHILD gethostbyname"); +#endif + HTAlert(LYStrerror(statuses.child_errno)); + if (errno == ENOMEM) { + /* + * Not much point in continuing, right? + * Fake a 'z', should shorten pointless + * guessing cycle. - kw + */ + LYFakeZap(YES); + } + } + } +#endif /* HAVE_H_ERRNO */ if (statuses.rehostentlen > sizeof(struct hostent)) { /* ** Then get the full reorganized hostent. -BL, kw @@ -1311,6 +1403,11 @@ PUBLIC CONST char * HTHostName NOARGS return hostname; } +#ifndef MULTINET /* SOCKET_ERRNO != errno ? */ +#if !defined(UCX) || !defined(VAXC) /* errno not modifiable ? */ +#define SOCKET_DEBUG_TRACE /* show errno status after some system calls */ +#endif /* UCX && VAXC */ +#endif /* MULTINET */ /* ** Interruptable connect as implemented for Mosaic by Marc Andreesen ** and hacked in for Lynx years ago by Lou Montulli, and further @@ -1449,6 +1546,13 @@ PUBLIC int HTDoConnect ARGS4( int ret; int tries=0; +#ifdef SOCKET_DEBUG_TRACE + { + int saved_errno = SOCKET_ERRNO; + HTInetStatus("this socket's first connect"); + errno = saved_errno; /* I don't trust HTInetStatus */ + } +#endif /* SOCKET_DEBUG_TRACE */ ret = 0; while (ret <= 0) { fd_set writefds; @@ -1477,6 +1581,13 @@ PUBLIC int HTDoConnect ARGS4( #endif /* SOCKS */ ret = select(FD_SETSIZE, NULL, (void *)&writefds, NULL, &timeout); +#ifdef SOCKET_DEBUG_TRACE + if (tries == 1) { + int saved_errno = SOCKET_ERRNO; + HTInetStatus("this socket's first select"); + errno = saved_errno; /* I don't trust HTInetStatus */ + } +#endif /* SOCKET_DEBUG_TRACE */ /* ** If we suspend, then it is possible that select will be ** interrupted. Allow for this possibility. - JED @@ -1484,6 +1595,13 @@ PUBLIC int HTDoConnect ARGS4( if ((ret == -1) && (errno == EINTR)) continue; +#ifdef SOCKET_DEBUG_TRACE + if (ret < 0) { + int saved_errno = SOCKET_ERRNO; + HTInetStatus("failed select"); + errno = saved_errno; /* I don't trust HTInetStatus */ + } +#endif /* SOCKET_DEBUG_TRACE */ /* ** Again according to the Sun and Motorola man pages for connect: ** EALREADY The socket is non-blocking and a previ- @@ -1527,8 +1645,16 @@ PUBLIC int HTDoConnect ARGS4( if (status && (SOCKET_ERRNO == EALREADY)) /* new stuff LJM */ ret = 0; /* keep going */ - else + else { +#ifdef SOCKET_DEBUG_TRACE + if (status < 0) { + int saved_errno = SOCKET_ERRNO; + HTInetStatus("confirm-ready connect"); + errno = saved_errno; + } +#endif /* SOCKET_DEBUG_TRACE */ break; + } #ifdef SOCKS } #endif /* SOCKS */ @@ -1559,6 +1685,11 @@ PUBLIC int HTDoConnect ARGS4( (SOCKET_ERRNO != 18242) && #endif /* UCX */ (SOCKET_ERRNO != EISCONN)) { +#ifdef SOCKET_DEBUG_TRACE + int saved_errno = SOCKET_ERRNO; + HTInetStatus("confirm-not-ready connect"); + errno = saved_errno; +#endif /* SOCKET_DEBUG_TRACE */ break; } } @@ -1570,6 +1701,13 @@ PUBLIC int HTDoConnect ARGS4( } } } +#ifdef SOCKET_DEBUG_TRACE + else if (status < 0) { + int saved_errno = SOCKET_ERRNO; + HTInetStatus("this socket's first and only connect"); + errno = saved_errno; /* I don't trust HTInetStatus */ + } +#endif /* SOCKET_DEBUG_TRACE */ #endif /* !DJGPP */ if (status < 0) { /* |