- hard links

[rsync/rsync.git] / io.c

diff --git a/io.c b/io.c
index fda04dd..3c55dbe 100644 (file)
--- 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)
 {
@@ -103,7 +104,15 @@ static int readfd(int fd,char *buffer,int N)
        read_buffer_p += ret;
        read_buffer_len -= ret;
       } else {
-       ret = read(fd,buffer + total,N - total);
+       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);
+         select(fd+1, &fds, NULL, NULL, NULL);
+       }
       }
 
       if (ret <= 0)
@@ -116,11 +125,13 @@ static int readfd(int fd,char *buffer,int N)
 
 int 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);
+      fprintf(FERROR,"Error reading %d bytes : %s\n",
+             4,ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_read += 4;
   return IVAL(b,0);
@@ -128,10 +139,12 @@ int read_int(int f)
 
 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);
+      fprintf(FERROR,"Error reading %d bytes : %s\n",
+             len,ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_read += len;
 }
@@ -143,10 +156,57 @@ unsigned char read_byte(int f)
   return (unsigned char)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) {
@@ -157,7 +217,7 @@ 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;
   }
@@ -179,8 +239,8 @@ 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) {
       read_check(buffer_f_in);
@@ -189,7 +249,7 @@ static int writefd(int fd,char *buf,int len)
       FD_SET(fd,&fds);
       tv.tv_sec = BLOCKING_TIMEOUT;
       tv.tv_usec = 0;
-      select(16,NULL,&fds,NULL,&tv);
+      select(fd+1,NULL,&fds,NULL,&tv);
     } else {
       total += ret;
     }
@@ -202,20 +262,24 @@ static int writefd(int fd,char *buf,int len)
 
 void write_int(int f,int 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) {
+    fprintf(FERROR,"write_int failed : %s\n",
+           ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_written += 4;
 }
 
 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) {
+    fprintf(FERROR,"write_buf failed : %s\n",
+           ret==-1?strerror(errno):"EOF");
+    exit_cleanup(1);
   }
   total_written += len;
 }