Made I/O more robust by handling EINTR

CONTRIBUTORS

@@ -126,3 +126,6 @@ Matjaz Thaler <matjaz.thaler@guest.arnes.si>
 
 Artur Skawina <skawina@geocities.com>
  for improving the font file generation in the Makefile
+
+Werner Fink <werner@suse.de>
+ for making I/O more robust by handling EINTR

HISTORY

@@ -622,7 +622,7 @@ Video Disk Recorder Revision History
 - Fixed calculating the timeout value in cFile::FileReady() (thanks to
   Wolfgang Henselmann-Weiss).
 
-2001-08-11: Version 0.91
+2001-08-12: Version 0.91
 
 - Fixed displaying colored button texts that are too long.
 - Suppressing replay progress display when replaying a DVD.
@@ -648,3 +648,4 @@ Video Disk Recorder Revision History
 - Fixed displaying editing marks when toggling a mark in "pause" mode.
 - If there is no free DVB device to record, the log message will now be given
   only once.
+- Made I/O more robust by handling EINTR (thanks to Werner Fink).

dvbapi.c

@@ -7,7 +7,7 @@
  * DVD support initially written by Andreas Schultz <aschultz@warp10.net>
  * based on dvdplayer-0.5 by Matjaz Thaler <matjaz.thaler@guest.arnes.si>
  *
- * $Id: dvbapi.c 1.105 2001/08/11 12:21:49 kls Exp $
+ * $Id: dvbapi.c 1.106 2001/08/12 15:09:42 kls Exp $
  */
 
 //#define DVDDEBUG        1
@@ -82,6 +82,8 @@ extern "C" {
 
 #define CHECK(s) { if ((s) < 0) LOG_ERROR; } // used for 'ioctl()' calls
 
+#define FATALERRNO (errno != EAGAIN && errno != EINTR)
+
 typedef unsigned char uchar;
 
 const char *IndexToHMSF(int Index, bool WithFrame)
@@ -158,7 +160,7 @@ cIndexFile::cIndexFile(const char *FileName, bool Record)
                  if (index) {
                     f = open(fileName, O_RDONLY);
                     if (f >= 0) {
-                       if ((int)read(f, index, buf.st_size) != buf.st_size) {
+                       if ((int)safe_read(f, index, buf.st_size) != buf.st_size) {
                           esyslog(LOG_ERR, "ERROR: can't read from file '%s'", fileName);
                           delete index;
                           index = NULL;
@@ -222,7 +224,7 @@ bool cIndexFile::CatchUp(void)
               int offset = (last + 1) * sizeof(tIndex);
               int delta = (newLast - last) * sizeof(tIndex);
               if (lseek(f, offset, SEEK_SET) == offset) {
-                 if (read(f, &index[last + 1], delta) != delta) {
+                 if (safe_read(f, &index[last + 1], delta) != delta) {
                     esyslog(LOG_ERR, "ERROR: can't read from index");
                     delete index;
                     index = NULL;
@@ -249,7 +251,7 @@ void cIndexFile::Write(uchar PictureType, uchar FileNumber, int FileOffset)
 {
   if (f >= 0) {
      tIndex i = { FileOffset, PictureType, FileNumber, 0 };
-     if (write(f, &i, sizeof(i)) != sizeof(i)) {
+     if (safe_write(f, &i, sizeof(i)) != sizeof(i)) {
         esyslog(LOG_ERR, "ERROR: can't write to index file");
         close(f);
         f = -1;
@@ -542,7 +544,7 @@ void cRecordBuffer::Input(void)
          t = time(NULL);
          }
       else if (r < 0) {
-         if (errno != EAGAIN) {
+         if (FATALERRNO) {
             LOG_ERROR;
             if (errno != EBUFFEROVERFLOW)
                break;
@@ -569,8 +571,9 @@ void cRecordBuffer::Output(void)
   int r = 0;
   for (;;) {
       int g = Get(b + r, sizeof(b) - r);
-      if (g > 0) {
+      if (g > 0)
          r += g;
+      if (r > 0) {
          int Count = r, Result;
          const uchar *p = remux.Process(b, Count, Result, &pictureType);
          if (p) {
@@ -580,7 +583,7 @@ void cRecordBuffer::Output(void)
                if (index && pictureType != NO_PICTURE)
                   index->Write(pictureType, fileName.Number(), fileSize);
                while (Result > 0) {
-                     int w = write(recordFile, p, Result);
+                     int w = safe_write(recordFile, p, Result);
                      if (w < 0) {
                         LOG_ERROR_STR(fileName.Name());
                         recording = false;
@@ -619,7 +622,7 @@ int ReadFrame(int f, uchar *b, int Length, int Max)
      esyslog(LOG_ERR, "ERROR: frame larger than buffer (%d > %d)", Length, Max);
      Length = Max;
      }
-  int r = read(f, b, Length);
+  int r = safe_read(f, b, Length);
   if (r < 0)
      LOG_ERROR;
   return r;
@@ -705,7 +708,7 @@ void cPlayBuffer::Output(void)
                         p += w;
                         r -= w;
                         }
-                     else if (w < 0 && errno != EAGAIN) {
+                     else if (w < 0 && FATALERRNO) {
                         LOG_ERROR;
                         Stop();
                         return;
@@ -922,7 +925,7 @@ void cReplayBuffer::Input(void)
               }
            else if (r == 0)
               eof = true;
-           else if (r < 0 && errno != EAGAIN) {
+           else if (r < 0 && FATALERRNO) {
               LOG_ERROR;
               break;
               }
@@ -2071,7 +2074,7 @@ void cTransferBuffer::Input(void)
               }
            }
         else if (r < 0) {
-           if (errno != EAGAIN) {
+           if (FATALERRNO) {
               LOG_ERROR;
               if (errno != EBUFFEROVERFLOW)
                  break;
@@ -2105,7 +2108,7 @@ void cTransferBuffer::Output(void)
                     p += w;
                     r -= w;
                     }
-                 else if (w < 0 && errno != EAGAIN) {
+                 else if (w < 0 && FATALERRNO) {
                     LOG_ERROR;
                     Stop();
                     return;
@@ -2214,7 +2217,7 @@ void cCuttingBuffer::Action(void)
                  }
               LastIFrame = 0;
               }
-           write(toFile, buffer, Length);
+           safe_write(toFile, buffer, Length);
            toIndex->Write(PictureType, toFileName->Number(), FileSize);
            FileSize += Length;
            if (!LastIFrame)

eit.c

@@ -13,7 +13,7 @@
  *   the Free Software Foundation; either version 2 of the License, or     *
  *   (at your option) any later version.                                   *
  *                                                                         *
- * $Id: eit.c 1.18 2001/08/11 14:51:28 kls Exp $
+ * $Id: eit.c 1.19 2001/08/12 15:04:37 kls Exp $
  ***************************************************************************/
 
 #include "eit.h"
@@ -1229,11 +1229,11 @@ void cSIProcessor::Action()
             {
                /* read section */
                unsigned char buf[4096+1]; // max. allowed size for any EIT section (+1 for safety ;-)
-               if (read(filters[a].handle, buf, 3) == 3)
+               if (safe_read(filters[a].handle, buf, 3) == 3)
                {
                   int seclen = ((buf[1] & 0x0F) << 8) | (buf[2] & 0xFF);
                   int pid = filters[a].pid;
-                  int n = read(filters[a].handle, buf + 3, seclen);
+                  int n = safe_read(filters[a].handle, buf + 3, seclen);
                   if (n == seclen)
                   {
                      seclen += 3;

recording.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: recording.c 1.32 2001/06/16 10:33:20 kls Exp $
+ * $Id: recording.c 1.33 2001/08/12 15:09:59 kls Exp $
  */
 
 #define _GNU_SOURCE
@@ -141,7 +141,7 @@ int cResumeFile::Read(void)
   if (fileName) {
      int f = open(fileName, O_RDONLY);
      if (f >= 0) {
-        if (read(f, &resume, sizeof(resume)) != sizeof(resume)) {
+        if (safe_read(f, &resume, sizeof(resume)) != sizeof(resume)) {
            resume = -1;
            LOG_ERROR_STR(fileName);
            }
@@ -158,7 +158,7 @@ bool cResumeFile::Save(int Index)
   if (fileName) {
      int f = open(fileName, O_WRONLY | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
      if (f >= 0) {
-        if (write(f, &Index, sizeof(Index)) != sizeof(Index))
+        if (safe_write(f, &Index, sizeof(Index)) != sizeof(Index))
            LOG_ERROR_STR(fileName);
         close(f);
         return true;
@@ -243,7 +243,7 @@ cRecording::cRecording(const char *FileName)
            int size = buf.st_size;
            summary = new char[size + 1]; // +1 for terminating 0
            if (summary) {
-              int rbytes = read(f, summary, size);
+              int rbytes = safe_read(f, summary, size);
               if (rbytes >= 0) {
                  summary[rbytes] = 0;
                  if (rbytes != size)

remote.c

@@ -6,7 +6,7 @@
  *
  * Ported to LIRC by Carsten Koch <Carsten.Koch@icem.de>  2000-06-16.
  *
- * $Id: remote.c 1.23 2001/07/27 10:17:19 kls Exp $
+ * $Id: remote.c 1.24 2001/08/12 15:07:26 kls Exp $
  */
 
 #include "remote.h"
@@ -199,7 +199,7 @@ int cRcIoRCU::ReceiveByte(int TimeoutMs)
   // Returns the byte if one was received within a timeout, -1 otherwise
   if (cFile::FileReady(f, TimeoutMs)) {
      unsigned char b;
-     if (read(f, &b, 1) == 1)
+     if (safe_read(f, &b, 1) == 1)
         return b;
      else
         LOG_ERROR;
@@ -436,7 +436,7 @@ void cRcIoLIRC::Action(void)
 
       LOCK_THREAD;
 
-      if (cFile::FileReady(f, REPEATLIMIT) && read(f, buf, sizeof(buf)) > 21) {
+      if (cFile::FileReady(f, REPEATLIMIT) && safe_read(f, buf, sizeof(buf)) > 21) {
          if (!receivedData) { // only accept new data the previous data has been fetched
             int count;
             sscanf(buf, "%*x %x %29s", &count, LastKeyName); // '29' in '%29s' is LIRC_KEY_BUF-1!

svdrp.c

@@ -10,7 +10,7 @@
  * and interact with the Video Disk Recorder - or write a full featured
  * graphical interface that sits on top of an SVDRP connection.
  *
- * $Id: svdrp.c 1.20 2001/07/22 13:58:48 kls Exp $
+ * $Id: svdrp.c 1.21 2001/08/12 15:10:16 kls Exp $
  */
 
 #define _GNU_SOURCE
@@ -264,7 +264,7 @@ bool cSVDRP::Send(const char *s, int length)
 {
   if (length < 0)
      length = strlen(s);
-  int wbytes = write(file, s, length);
+  int wbytes = safe_write(file, s, length);
   if (wbytes == length)
      return true;
   if (wbytes < 0) {
@@ -920,7 +920,7 @@ void cSVDRP::Process(void)
         lastActivity = time(NULL);
      if (file.Ready(false)) {
         unsigned char c;
-        int r = read(file, &c, 1);
+        int r = safe_read(file, &c, 1);
         if (r > 0) {
            if (c == '\n' || c == 0x00) {
               // strip trailing whitespace:

tools.c

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: tools.c 1.38 2001/08/11 14:49:48 kls Exp $
+ * $Id: tools.c 1.39 2001/08/12 15:12:54 kls Exp $
  */
 
 #define _GNU_SOURCE
@@ -23,9 +23,33 @@
 
 int SysLogLevel = 3;
 
+ssize_t safe_read(int filedes, void *buffer, size_t size)
+{
+  for (;;) {
+      ssize_t p = read(filedes, buffer, size);
+      if (p < 0 && errno == EINTR) {
+         dsyslog(LOG_INFO, "EINTR while reading from file handle %d - retrying", filedes);
+         continue;
+         }
+      return p;
+      }
+}
+
+ssize_t safe_write(int filedes, const void *buffer, size_t size)
+{
+  for (;;) {
+      ssize_t p = write(filedes, buffer, size);
+      if (p < 0 && errno == EINTR) {
+         dsyslog(LOG_INFO, "EINTR while writing to file handle %d - retrying", filedes);
+         continue;
+         }
+      return p;
+      }
+}
+
 void writechar(int filedes, char c)
 {
-  write(filedes, &c, sizeof(c));
+  safe_write(filedes, &c, sizeof(c));
 }
 
 char *readline(FILE *f)

tools.h

@@ -4,7 +4,7 @@
  * See the main source file 'vdr.c' for copyright information and
  * how to reach the author.
  *
- * $Id: tools.h 1.27 2001/08/11 09:52:14 kls Exp $
+ * $Id: tools.h 1.28 2001/08/12 15:13:02 kls Exp $
  */
 
 #ifndef __TOOLS_H
@@ -33,6 +33,8 @@ extern int SysLogLevel;
 
 template<class T> inline void swap(T &a, T &b) { T t = a; a = b; b = t; };
 
+ssize_t safe_read(int filedes, void *buffer, size_t size);
+ssize_t safe_write(int filedes, const void *buffer, size_t size);
 void writechar(int filedes, char c);
 char *readline(FILE *f);
 char *strn0cpy(char *dest, const char *src, size_t n);