rosapps/applications/net/ncftp/sio/SRead.c

   1 #include "syshdrs.h"
   2
   3 static char UNUSED(gSioVersion[]) = "@(#) sio 6.0.3 ** Copyright 1992-2001 Mike Gleason. All rights reserved.";
   4
   5 #ifdef NO_SIGNALS
   6 static char UNUSED(gNoSignalsMarker[]) = "@(#) sio - NO_SIGNALS";
   7 #else
   8 extern volatile Sjmp_buf gNetTimeoutJmp;
   9 extern volatile Sjmp_buf gPipeJmp;
  10 #endif
  11
  12 /* Read up to "size" bytes on sfd before "tlen" seconds.
  13  *
  14  * If "retry" is on, after a successful read of less than "size"
  15  * bytes, it will attempt to read more, upto "size."
  16  *
  17  * If the timer elapses and one or more bytes were read, it returns
  18  * that number, otherwise a timeout error is returned.
  19  *
  20  * Although "retry" would seem to indicate you may want to always
  21  * read "size" bytes or else it is an error, even with that on you
  22  * may get back a value < size.  Set "retry" to 0 when you want to
  23  * return as soon as there is a chunk of data whose size is <= "size".
  24  */
  25
  26 #ifndef NO_SIGNALS
  27
  28 int
  29 SRead(int sfd, char *const buf0, size_t size, int tlen, int retry)
  30 {
  31         int nread;
  32         volatile int nleft;
  33         char *volatile buf = buf0;
  34         int tleft;
  35         vsio_sigproc_t sigalrm, sigpipe;
  36         time_t done, now;
  37
  38         if (SSetjmp(gNetTimeoutJmp) != 0) {
  39                 alarm(0);
  40                 (void) SSignal(SIGALRM, (sio_sigproc_t) sigalrm);
  41                 (void) SSignal(SIGPIPE, (sio_sigproc_t) sigpipe);
  42                 nread = size - nleft;
  43                 if ((nread > 0) && ((retry & (kFullBufferRequired|kFullBufferRequiredExceptLast)) == 0))
  44                         return (nread);
  45                 errno = ETIMEDOUT;
  46                 return (kTimeoutErr);
  47         }
  48
  49         if (SSetjmp(gPipeJmp) != 0) {
  50                 alarm(0);
  51                 (void) SSignal(SIGALRM, (sio_sigproc_t) sigalrm);
  52                 (void) SSignal(SIGPIPE, (sio_sigproc_t) sigpipe);
  53                 nread = size - nleft;
  54                 if ((nread > 0) && ((retry & (kFullBufferRequired|kFullBufferRequiredExceptLast)) == 0))
  55                         return (nread);
  56                 errno = EPIPE;
  57                 return (kBrokenPipeErr);
  58         }
  59
  60         sigalrm = (vsio_sigproc_t) SSignal(SIGALRM, SIOHandler);
  61         sigpipe = (vsio_sigproc_t) SSignal(SIGPIPE, SIOHandler);
  62         errno = 0;
  63
  64         nleft = (int) size;
  65         time(&now);
  66         done = now + tlen;
  67         forever {
  68                 tleft = (int) (done - now);
  69                 if (tleft < 1) {
  70                         nread = size - nleft;
  71                         if ((nread == 0) || ((retry & (kFullBufferRequired)) != 0)) {
  72                                 nread = kTimeoutErr;
  73                                 errno = ETIMEDOUT;
  74                         }
  75                         goto done;
  76                 }
  77                 (void) alarm((unsigned int) tleft);
  78                 nread = read(sfd, (char *) buf, nleft);
  79                 (void) alarm(0);
  80                 if (nread <= 0) {
  81                         if (nread == 0) {
  82                                 /* EOF */
  83                                 if (retry == ((retry & (kFullBufferRequiredExceptLast)) != 0))
  84                                         nread = size - nleft;
  85                                 goto done;
  86                         } else if (errno != EINTR) {
  87                                 nread = size - nleft;
  88                                 if (nread == 0)
  89                                         nread = -1;
  90                                 goto done;
  91                         } else {
  92                                 errno = 0;
  93                                 nread = 0;
  94                                 /* Try again. */
  95
  96                                 /* Ignore this line... */
  97                                 LIBSIO_USE_VAR(gSioVersion);
  98                         }
  99                 }
 100                 nleft -= nread;
 101                 if ((nleft <= 0) || (((retry & (kFullBufferRequired|kFullBufferRequiredExceptLast)) == 0) && (nleft != (int) size)))
 102                         break;
 103                 buf += nread;
 104                 time(&now);
 105         }
 106         nread = size - nleft;
 107
 108 done:
 109         (void) SSignal(SIGALRM, (sio_sigproc_t) sigalrm);
 110         (void) SSignal(SIGPIPE, (sio_sigproc_t) sigpipe);
 111
 112         return (nread);
 113 }       /* SRead */
 114
 115 #else
 116
 117 int
 118 SRead(int sfd, char *const buf0, size_t size, int tlen, int retry)
 119 {
 120         int nread;
 121         volatile int nleft;
 122         char *buf = buf0;
 123         int tleft;
 124         time_t done, now;
 125         fd_set ss;
 126         struct timeval tv;
 127         int result, firstRead;
 128
 129         errno = 0;
 130
 131         nleft = (int) size;
 132         time(&now);
 133         done = now + tlen;
 134         firstRead = 1;
 135
 136         forever {
 137                 tleft = (int) (done - now);
 138                 if (tleft < 1) {
 139                         nread = size - nleft;
 140                         if ((nread == 0) || ((retry & (kFullBufferRequired|kFullBufferRequiredExceptLast)) != 0)) {
 141                                 nread = kTimeoutErr;
 142                                 errno = ETIMEDOUT;
 143                                 SETWSATIMEOUTERR
 144                         }
 145                         goto done;
 146                 }
 147
 148                 if (!firstRead || ((retry & kNoFirstSelect) == 0)) {
 149                         forever {
 150                                 errno = 0;
 151                                 FD_ZERO(&ss);
 152                                 FD_SET(sfd, &ss);
 153                                 tv.tv_sec = tlen;
 154                                 tv.tv_usec = 0;
 155                                 result = select(sfd + 1, SELECT_TYPE_ARG234 &ss, NULL, NULL, SELECT_TYPE_ARG5 &tv);
 156                                 if (result == 1) {
 157                                         /* ready */
 158                                         break;
 159                                 } else if (result == 0) {
 160                                         /* timeout */
 161                                         nread = size - nleft;
 162                                         if ((nread > 0) && ((retry & (kFullBufferRequired|kFullBufferRequiredExceptLast)) == 0))
 163                                                 return (nread);
 164                                         errno = ETIMEDOUT;
 165                                         SETWSATIMEOUTERR
 166                                                 return (kTimeoutErr);
 167                                 } else if (errno != EINTR) {
 168                                         return (-1);
 169                                 }
 170                         }
 171                         firstRead = 0;
 172                 }
 173
 174 #if defined(WIN32) || defined(_WINDOWS)
 175                 nread = recv(sfd, (char *) buf, nleft, 0);
 176 #else
 177                 nread = read(sfd, (char *) buf, nleft);
 178 #endif
 179
 180                 if (nread <= 0) {
 181                         if (nread == 0) {
 182                                 /* EOF */
 183                                 if (retry == ((retry & (kFullBufferRequiredExceptLast)) != 0))
 184                                         nread = size - nleft;
 185                                 goto done;
 186                         } else if (errno != EINTR) {
 187                                 nread = size - nleft;
 188                                 if (nread == 0)
 189                                         nread = -1;
 190                                 goto done;
 191                         } else {
 192                                 errno = 0;
 193                                 nread = 0;
 194                                 /* Try again. */
 195
 196                                 /* Ignore these two lines */
 197                                 LIBSIO_USE_VAR(gSioVersion);
 198                                 LIBSIO_USE_VAR(gNoSignalsMarker);
 199                         }
 200                 }
 201                 nleft -= nread;
 202                 if ((nleft <= 0) || (((retry & (kFullBufferRequired|kFullBufferRequiredExceptLast)) == 0) && (nleft != (int) size)))
 203                         break;
 204                 buf += nread;
 205                 time(&now);
 206         }
 207         nread = size - nleft;
 208
 209 done:
 210         return (nread);
 211 }       /* SRead */
 212
 213 #endif