X-Git-Url: https://mattmccutchen.net/rsync/rsync.git/blobdiff_plain/7f28dbee65cef6e1990552c3eb3eb450ef9e98f2..97d6916e2df3d6f935e4d57f162a44a77377064c:/io.c

diff --git a/io.c b/io.c
index 38868751..0e75f6bd 100644
--- a/io.c
+++ b/io.c
@@ -28,6 +28,7 @@ static int total_written = 0;
 static int total_read = 0;
 
 extern int verbose;
+extern int sparse_files;
 
 int write_total(void)
 {
@@ -61,6 +62,8 @@ static void read_check(int f)
 {
   int n;
 
+  if (f == -1) return;
+
   if (read_buffer_len == 0) {
     read_buffer_p = read_buffer;
   }
@@ -68,6 +71,9 @@ 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;
@@ -94,10 +100,13 @@ static int readfd(int fd,char *buffer,int N)
 {
   int  ret;
   int total=0;  
+
+  if (read_buffer_len < N)
+	  read_check(buffer_f_in);
  
   while (total < N)
     {
-      if (read_buffer_len > 0) {
+      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;
@@ -128,9 +137,9 @@ int read_int(int f)
   char b[4];
   if ((ret=readfd(f,b,4)) != 4) {
     if (verbose > 1) 
-      fprintf(stderr,"Error reading %d bytes : %s\n",
-	      4,ret==-1?strerror(errno):"EOF");
-    exit(1);
+      fprintf(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);
@@ -141,24 +150,71 @@ void read_buf(int f,char *buf,int len)
   int ret;
   if ((ret=readfd(f,buf,len)) != len) {
     if (verbose > 1) 
-      fprintf(stderr,"Error reading %d bytes : %s\n",
-	      len,ret==-1?strerror(errno):"EOF");
-    exit(1);
+      fprintf(FERROR,"(%d) Error reading %d bytes : %s\n",
+	      getpid(),len,ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_read += len;
 }
 
 unsigned char read_byte(int f)
 {
-  char c;
-  read_buf(f,&c,1);
-  return (unsigned char)c;
+  unsigned char c;
+  read_buf(f,(char *)&c,1);
+  return c;
+}
+
+
+static char last_byte=0;
+static int last_sparse = 0;
+
+int sparse_end(int f)
+{
+  if (last_sparse) {
+    lseek(f,-1,SEEK_CUR);
+    return (write(f,&last_byte,1) == 1 ? 0 : -1);
+  }
+  last_sparse = 0;
+  return 0;
+}
+
+int write_sparse(int f,char *buf,int len)
+{
+  int l1=0,l2=0;
+  int ret;
+
+  if (!sparse_files) 
+    return write(f,buf,len);
+
+  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)
+    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)
+    lseek(f,l2,SEEK_CUR);
+
+  return len;
 }
 
 int read_write(int fd_in,int fd_out,int size)
 {
   static char *buf=NULL;
-  static int bufsize = WRITE_BLOCK_SIZE;
+  int bufsize = sparse_files?SPARSE_WRITE_SIZE:WRITE_SIZE;
   int total=0;
   
   if (!buf) {
@@ -169,7 +225,7 @@ int read_write(int fd_in,int fd_out,int size)
   while (total < size) {
     int n = MIN(size-total,bufsize);
     read_buf(fd_in,buf,n);
-    if (write(fd_out,buf,n) != n)
+    if (write_sparse(fd_out,buf,n) != n)
       return total;
     total += n;
   }
@@ -180,7 +236,8 @@ int read_write(int fd_in,int fd_out,int size)
 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) 
@@ -194,14 +251,47 @@ static int writefd(int fd,char *buf,int len)
     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) */
+#if 0
+	    fprintf(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(fd+1,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) 
+		      fprintf(FERROR,"select error: %s\n", strerror(errno));
+	      exit_cleanup(1);
+      }
+
+      if (count == 0) continue;
+      
+      if (FD_ISSET(fd, &w_fds)) {
+	      got_select = 1;
+      }
     } else {
       total += ret;
     }
@@ -218,9 +308,9 @@ void write_int(int f,int x)
   char b[4];
   SIVAL(b,0,x);
   if ((ret=writefd(f,b,4)) != 4) {
-    fprintf(stderr,"write_int failed : %s\n",
+    fprintf(FERROR,"write_int failed : %s\n",
 	    ret==-1?strerror(errno):"EOF");
-    exit(1);
+    exit_cleanup(1);
   }
   total_written += 4;
 }
@@ -229,9 +319,9 @@ void write_buf(int f,char *buf,int len)
 {
   int ret;
   if ((ret=writefd(f,buf,len)) != len) {
-    fprintf(stderr,"write_buf failed : %s\n",
+    fprintf(FERROR,"write_buf failed : %s\n",
 	    ret==-1?strerror(errno):"EOF");
-    exit(1);
+    exit_cleanup(1);
   }
   total_written += len;
 }