fixed a select bug which caused rsync to use far more cpu time than
[rsync/rsync.git] / io.c
diff --git a/io.c b/io.c
index 22e5b3d..52c4cb1 100644 (file)
--- a/io.c
+++ b/io.c
   */
 #include "rsync.h"
 
-static int total_written = 0;
-static int total_read = 0;
+static int64 total_written;
+static int64 total_read;
 
 extern int verbose;
+extern int sparse_files;
+extern int io_timeout;
 
-int write_total(void)
+int64 write_total(void)
 {
   return total_written;
 }
 
-int read_total(void)
+int64 read_total(void)
 {
   return total_read;
 }
@@ -48,10 +50,10 @@ void setup_nonblocking(int f_in,int f_out)
 }
 
 
-static char *read_buffer = NULL;
-static char *read_buffer_p = NULL;
-static int read_buffer_len = 0;
-static int read_buffer_size = 0;
+static char *read_buffer;
+static char *read_buffer_p;
+static int read_buffer_len;
+static int read_buffer_size;
 
 
 /* This function was added to overcome a deadlock problem when using
@@ -61,6 +63,8 @@ static void read_check(int f)
 {
   int n;
 
+  if (f == -1) return;
+
   if (read_buffer_len == 0) {
     read_buffer_p = read_buffer;
   }
@@ -68,6 +72,9 @@ static void read_check(int f)
   if ((n=num_waiting(f)) <= 0)
     return;
 
+  /* things could deteriorate if we read in really small chunks */
+  if (n < 10) n = 1024;
+
   if (read_buffer_p != read_buffer) {
     memmove(read_buffer,read_buffer_p,read_buffer_len);
     read_buffer_p = read_buffer;
@@ -89,80 +96,216 @@ static void read_check(int f)
   }
 }
 
+static time_t last_io;
 
-static int readfd(int fd,char *buffer,int N)
+
+static void check_timeout(void)
 {
-  int  ret;
-  int total=0;  
-  while (total < N)
-    {
-      if (read_buffer_len > 0) {
-       ret = MIN(read_buffer_len,N-total);
-       memcpy(buffer+total,read_buffer_p,ret);
-       read_buffer_p += ret;
-       read_buffer_len -= ret;
-      } else {
-       ret = read(fd,buffer + total,N - total);
-      }
+       time_t t;
+       
+       if (!io_timeout) return;
+
+       if (!last_io) {
+               last_io = time(NULL);
+               return;
+       }
+
+       t = time(NULL);
+
+       if (last_io && io_timeout && (t-last_io)>io_timeout) {
+               rprintf(FERROR,"read timeout after %d second - exiting\n", 
+                       (int)(t-last_io));
+               exit_cleanup(1);
+       }
+}
 
-      if (ret <= 0)
+static int readfd(int fd,char *buffer,int N)
+{
+       int  ret;
+       int total=0;  
+       struct timeval tv;
+       
+       if (read_buffer_len < N)
+               read_check(buffer_f_in);
+       
+       while (total < N) {
+               if (read_buffer_len > 0 && buffer_f_in == fd) {
+                       ret = MIN(read_buffer_len,N-total);
+                       memcpy(buffer+total,read_buffer_p,ret);
+                       read_buffer_p += ret;
+                       read_buffer_len -= ret;
+                       total += ret;
+                       continue;
+               } 
+
+               while ((ret = read(fd,buffer + total,N-total)) == -1) {
+                       fd_set fds;
+
+                       if (errno != EAGAIN && errno != EWOULDBLOCK)
+                               return -1;
+                       FD_ZERO(&fds);
+                       FD_SET(fd, &fds);
+                       tv.tv_sec = io_timeout;
+                       tv.tv_usec = 0;
+
+                       if (select(fd+1, &fds, NULL, NULL, 
+                                  io_timeout?&tv:NULL) != 1) {
+                               check_timeout();
+                       }
+               }
+
+               if (ret <= 0)
+                       return total;
+               total += ret;
+       }
+
+       if (io_timeout)
+               last_io = time(NULL);
        return total;
-      total += ret;
-    }
-  return total;
 }
 
 
-int read_int(int f)
+int32 read_int(int f)
 {
+  int ret;
   char b[4];
-  if (readfd(f,b,4) != 4) {
+  if ((ret=readfd(f,b,4)) != 4) {
     if (verbose > 1) 
-      fprintf(stderr,"Error reading %d bytes : %s\n",4,strerror(errno));
-    exit(1);
+      rprintf(FERROR,"(%d) Error reading %d bytes : %s\n",
+             getpid(),4,ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_read += 4;
   return IVAL(b,0);
 }
 
+int64 read_longint(int f)
+{
+       extern int remote_version;
+       int64 ret;
+       char b[8];
+       ret = read_int(f);
+
+       if ((int32)ret != (int32)0xffffffff) return ret;
+
+#ifdef NO_INT64
+       rprintf(FERROR,"Integer overflow - attempted 64 bit offset\n");
+       exit_cleanup(1);
+#else
+       if (remote_version >= 16) {
+               if ((ret=readfd(f,b,8)) != 8) {
+                       if (verbose > 1) 
+                               rprintf(FERROR,"(%d) Error reading %d bytes : %s\n",
+                                       getpid(),8,ret==-1?strerror(errno):"EOF");
+                       exit_cleanup(1);
+               }
+               total_read += 8;
+               ret = IVAL(b,0) | (((int64)IVAL(b,4))<<32);
+       }
+#endif
+
+       return ret;
+}
+
 void read_buf(int f,char *buf,int len)
 {
-  if (readfd(f,buf,len) != len) {
+  int ret;
+  if ((ret=readfd(f,buf,len)) != len) {
     if (verbose > 1) 
-      fprintf(stderr,"Error reading %d bytes : %s\n",len,strerror(errno));
-    exit(1);
+      rprintf(FERROR,"(%d) Error reading %d bytes : %s\n",
+             getpid(),len,ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_read += len;
 }
 
+void read_sbuf(int f,char *buf,int len)
+{
+       read_buf(f,buf,len);
+       buf[len] = 0;
+}
+
+unsigned char read_byte(int f)
+{
+  unsigned char c;
+  read_buf(f,(char *)&c,1);
+  return c;
+}
+
 
-int read_write(int fd_in,int fd_out,int size)
+static char last_byte;
+static int last_sparse;
+
+int sparse_end(int f)
 {
-  static char *buf=NULL;
-  static int bufsize = WRITE_BLOCK_SIZE;
-  int total=0;
-  
-  if (!buf) {
-    buf = (char *)malloc(bufsize);
-    if (!buf) out_of_memory("read_write");
-  }
+       if (last_sparse) {
+               do_lseek(f,-1,SEEK_CUR);
+               return (write(f,&last_byte,1) == 1 ? 0 : -1);
+       }
+       last_sparse = 0;
+       return 0;
+}
 
-  while (total < size) {
-    int n = MIN(size-total,bufsize);
-    read_buf(fd_in,buf,n);
-    if (write(fd_out,buf,n) != n)
-      return total;
-    total += n;
-  }
-  return total;
+
+static int write_sparse(int f,char *buf,int len)
+{
+       int l1=0,l2=0;
+       int ret;
+
+       for (l1=0;l1<len && buf[l1]==0;l1++) ;
+       for (l2=0;l2<(len-l1) && buf[len-(l2+1)]==0;l2++) ;
+
+       last_byte = buf[len-1];
+
+       if (l1 == len || l2 > 0)
+               last_sparse=1;
+
+       if (l1 > 0)
+               do_lseek(f,l1,SEEK_CUR);  
+
+       if (l1 == len) 
+               return len;
+
+       if ((ret=write(f,buf+l1,len-(l1+l2))) != len-(l1+l2)) {
+               if (ret == -1 || ret == 0) return ret;
+               return (l1+ret);
+       }
+
+       if (l2 > 0)
+               do_lseek(f,l2,SEEK_CUR);
+       
+       return len;
+}
+
+
+
+int write_file(int f,char *buf,int len)
+{
+       int ret = 0;
+
+       if (!sparse_files) 
+               return write(f,buf,len);
+
+       while (len>0) {
+               int len1 = MIN(len, SPARSE_WRITE_SIZE);
+               int r1 = write_sparse(f, buf, len1);
+               if (r1 <= 0) {
+                       if (ret > 0) return ret;
+                       return r1;
+               }
+               len -= r1;
+               buf += r1;
+               ret += r1;
+       }
+       return ret;
 }
 
 
 static int writefd(int fd,char *buf,int len)
 {
   int total = 0;
-  fd_set fds;
+  fd_set w_fds, r_fds;
+  int fd_count, count, got_select=0;
   struct timeval tv;
 
   if (buffer_f_in == -1) 
@@ -173,50 +316,169 @@ static int writefd(int fd,char *buf,int len)
 
     if (ret == 0) return total;
 
-    if (ret == -1 && errno != EWOULDBLOCK) 
-      return total?total:-1;
+    if (ret == -1 && !(errno == EWOULDBLOCK || errno == EAGAIN)) 
+      return -1;
+
+    if (ret == -1 && got_select) {
+           /* hmmm, we got a write select on the fd and then failed to write.
+              Why doesn't that mean that the fd is dead? It doesn't on some
+              systems it seems (eg. IRIX) */
+           u_sleep(1000);
+#if 0
+           rprintf(FERROR,"write exception\n");
+           exit_cleanup(1);
+#endif
+    }
+
+    got_select = 0;
+
 
     if (ret == -1) {
       read_check(buffer_f_in);
 
-      FD_ZERO(&fds);
-      FD_SET(fd,&fds);
+      fd_count = fd+1;
+      FD_ZERO(&w_fds);
+      FD_ZERO(&r_fds);
+      FD_SET(fd,&w_fds);
+      if (buffer_f_in != -1) {
+             FD_SET(buffer_f_in,&r_fds);
+             if (buffer_f_in > fd) 
+                     fd_count = buffer_f_in+1;
+      }
+
       tv.tv_sec = BLOCKING_TIMEOUT;
       tv.tv_usec = 0;
-      select(16,NULL,&fds,NULL,&tv);
+      count = select(fd_count,buffer_f_in == -1? NULL: &r_fds,
+                    &w_fds,NULL,&tv);
+      if (count == -1 && errno != EINTR) {
+             if (verbose > 1) 
+                     rprintf(FERROR,"select error: %s\n", strerror(errno));
+             exit_cleanup(1);
+      }
+
+      if (count == 0) {
+             check_timeout();
+             continue;
+      }
+      
+      if (FD_ISSET(fd, &w_fds)) {
+             got_select = 1;
+      }
     } else {
       total += ret;
     }
   }
 
+  if (io_timeout)
+         last_io = time(NULL);
+
   return total;
 }
 
 
 
-void write_int(int f,int x)
+void write_int(int f,int32 x)
 {
+  int ret;
   char b[4];
   SIVAL(b,0,x);
-  if (writefd(f,b,4) != 4) {
-    fprintf(stderr,"write_int failed : %s\n",strerror(errno));
-    exit(1);
+  if ((ret=writefd(f,b,4)) != 4) {
+    rprintf(FERROR,"write_int failed : %s\n",
+           ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_written += 4;
 }
 
+void write_longint(int f, int64 x)
+{
+       extern int remote_version;
+       char b[8];
+       int ret;
+
+       if (remote_version < 16 || x <= 0x7FFFFFFF) {
+               write_int(f, (int)x);
+               return;
+       }
+
+       write_int(f, -1);
+       SIVAL(b,0,(x&0xFFFFFFFF));
+       SIVAL(b,4,((x>>32)&0xFFFFFFFF));
+
+       if ((ret=writefd(f,b,8)) != 8) {
+               rprintf(FERROR,"write_longint failed : %s\n",
+                       ret==-1?strerror(errno):"EOF");
+               exit_cleanup(1);
+       }
+       total_written += 8;
+}
+
 void write_buf(int f,char *buf,int len)
 {
-  if (writefd(f,buf,len) != len) {
-    fprintf(stderr,"write_buf failed : %s\n",strerror(errno));
-    exit(1);
+  int ret;
+  if ((ret=writefd(f,buf,len)) != len) {
+    rprintf(FERROR,"write_buf failed : %s\n",
+           ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_written += len;
 }
 
+/* write a string to the connection */
+void write_sbuf(int f,char *buf)
+{
+       write_buf(f, buf, strlen(buf));
+}
+
+
+void write_byte(int f,unsigned char c)
+{
+       write_buf(f,(char *)&c,1);
+}
 
 void write_flush(int f)
 {
 }
 
 
+int read_line(int f, char *buf, int maxlen)
+{
+       while (maxlen) {
+               read_buf(f, buf, 1);
+               if (buf[0] == '\n') {
+                       buf[0] = 0;
+                       break;
+               }
+               if (buf[0] != '\r') {
+                       buf++;
+                       maxlen--;
+               }
+       }
+       if (maxlen == 0) {
+               *buf = 0;
+               return 0;
+       }
+       return 1;
+}
+
+
+void io_printf(int fd, const char *format, ...)
+{
+       va_list ap;  
+       char buf[1024];
+       int len;
+       
+       va_start(ap, format);
+
+#if HAVE_VSNPRINTF
+       len = vsnprintf(buf, sizeof(buf)-1, format, ap);
+#else
+       vsprintf(buf, format, ap);
+       len = strlen(buf);
+#endif
+       va_end(ap);
+
+       if (len < 0) exit_cleanup(1);
+
+       write_sbuf(fd, buf);
+}