X-Git-Url: http://git.annexia.org/?p=libguestfs.git;a=blobdiff_plain;f=daemon%2Ftar.c;h=072a56693ec33f40ae9c221508ea77176abb18de;hp=30085741c7f787e3a6439ff68472eb1d006caf88;hb=4d900cdac8258daa2e99c6ceb2a4985154e94150;hpb=78029b529ad98769685d607230b70f71832d5906

diff --git a/daemon/tar.c b/daemon/tar.c
index 3008574..072a566 100644
--- a/daemon/tar.c
+++ b/daemon/tar.c
@@ -23,63 +23,99 @@
 #include <string.h>
 #include <fcntl.h>
 
-#include "../src/guestfs_protocol.h"
+#include "read-file.h"
+
+#include "guestfs_protocol.h"
 #include "daemon.h"
 #include "actions.h"
+#include "optgroups.h"
+
+int
+optgroup_xz_available (void)
+{
+  int r = access ("/usr/bin/xz", X_OK);
+  return r == 0;
+}
+
+/* Redirect errors from the tar command to the error file, then
+ * provide functions for reading it in.  We overwrite the file each
+ * time, and since it's small and stored on the appliance we don't
+ * bother to delete it.
+ */
+static const char *error_file = "/tmp/error";
+
+static char *
+read_error_file (void)
+{
+  size_t len;
+  char *str = read_file (error_file, &len);
+  if (str == NULL) {
+    str = strdup ("(no error)");
+    if (str == NULL) {
+      perror ("strdup");
+      exit (EXIT_FAILURE);
+    }
+    len = strlen (str);
+  }
+
+  /* Remove trailing \n character if any. */
+  if (len > 0 && str[len-1] == '\n')
+    str[--len] = '\0';
+
+  return str;                   /* caller frees */
+}
 
 static int
-fwrite_cb (void *fp_ptr, const void *buf, int len)
+write_cb (void *fd_ptr, const void *buf, size_t len)
 {
-  FILE *fp = *(FILE **)fp_ptr;
-  return fwrite (buf, len, 1, fp) == 1 ? 0 : -1;
+  int fd = *(int *)fd_ptr;
+  return xwrite (fd, buf, len);
 }
 
 /* Has one FileIn parameter. */
-int
-do_tar_in (char *dir)
+static int
+do_tXz_in (const char *dir, const char *filter)
 {
-  int err, r, len;
+  int err, r;
   FILE *fp;
   char *cmd;
 
-  if (!root_mounted || dir[0] != '/') {
-    cancel_receive ();
-    reply_with_error ("tar-in: root must be mounted and path must be absolute");
-    return -1;
-  }
-
   /* "tar -C /sysroot%s -xf -" but we have to quote the dir. */
-  len = 2 * strlen (dir) + sysroot_len + 32;
-  cmd = malloc (len);
-  if (!cmd) {
+  if (asprintf_nowarn (&cmd, "tar -C %R -%sxf - 2> %s",
+                       dir, filter, error_file) == -1) {
     err = errno;
-    cancel_receive ();
+    r = cancel_receive ();
     errno = err;
-    reply_with_perror ("malloc");
+    if (r != -2) reply_with_perror ("asprintf");
     return -1;
   }
-  strcpy (cmd, "tar -C ");
-  strcat (cmd, sysroot);
-  shell_quote (cmd+15, len-15, dir);
-  strcat (cmd, " -xf -");
+
+  if (verbose)
+    fprintf (stderr, "%s\n", cmd);
 
   fp = popen (cmd, "w");
   if (fp == NULL) {
     err = errno;
-    cancel_receive ();
+    r = cancel_receive ();
     errno = err;
-    reply_with_perror ("%s", cmd);
+    if (r != -2) reply_with_perror ("%s", cmd);
     free (cmd);
     return -1;
   }
   free (cmd);
 
-  r = receive_file (fwrite_cb, &fp);
+  /* The semantics of fwrite are too undefined, so write to the
+   * file descriptor directly instead.
+   */
+  int fd = fileno (fp);
+
+  r = receive_file (write_cb, &fd);
   if (r == -1) {		/* write error */
-    err = errno;
-    cancel_receive ();
-    errno = err;
-    reply_with_perror ("write: %s", dir);
+    if (cancel_receive () != -2) {
+      char *errstr = read_error_file ();
+      reply_with_error ("write error on directory: %s: %s", dir, errstr);
+      free (errstr);
+    }
     pclose (fp);
     return -1;
   }
@@ -90,167 +126,58 @@ do_tar_in (char *dir)
   }
 
   if (pclose (fp) != 0) {
-    err = errno;
-    cancel_receive ();
-    errno = err;
-    reply_with_perror ("pclose: %s", dir);
+    if (r == -1)                /* if r == 0, file transfer ended already */
+      r = cancel_receive ();
+    if (r != -2) {
+      char *errstr = read_error_file ();
+      reply_with_error ("tar subcommand failed on directory: %s: %s",
+                        dir, errstr);
+      free (errstr);
+    }
     return -1;
   }
 
   return 0;
 }
 
-/* Has one FileOut parameter. */
+/* Has one FileIn parameter. */
 int
-do_tar_out (char *dir)
+do_tar_in (const char *dir)
 {
-  int r, len;
-  FILE *fp;
-  char *cmd;
-  char buf[GUESTFS_MAX_CHUNK_SIZE];
-
-  NEED_ROOT (-1);
-  ABS_PATH (dir, -1);
-
-  /* "tar -C /sysroot%s -cf - ." but we have to quote the dir. */
-  len = 2 * strlen (dir) + sysroot_len + 32;
-  cmd = malloc (len);
-  if (!cmd) {
-    reply_with_perror ("malloc");
-    return -1;
-  }
-  strcpy (cmd, "tar -C ");
-  strcat (cmd, sysroot);
-  shell_quote (cmd+15, len-15, dir);
-  strcat (cmd, " -cf - .");
-
-  fp = popen (cmd, "r");
-  if (fp == NULL) {
-    reply_with_perror ("%s", cmd);
-    free (cmd);
-    return -1;
-  }
-  free (cmd);
-
-  /* Now we must send the reply message, before the file contents.  After
-   * this there is no opportunity in the protocol to send any error
-   * message back.  Instead we can only cancel the transfer.
-   */
-  reply (NULL, NULL);
-
-  while ((r = fread (buf, 1, sizeof buf, fp)) > 0) {
-    if (send_file_write (buf, r) < 0) {
-      pclose (fp);
-      return -1;
-    }
-  }
-
-  if (ferror (fp)) {
-    perror (dir);
-    send_file_end (1);		/* Cancel. */
-    pclose (fp);
-    return -1;
-  }
-
-  if (pclose (fp) != 0) {
-    perror (dir);
-    send_file_end (1);		/* Cancel. */
-    return -1;
-  }
-
-  send_file_end (0);		/* Normal end of file. */
-  return 0;
+  return do_tXz_in (dir, "");
 }
 
 /* Has one FileIn parameter. */
 int
-do_tgz_in (char *dir)
+do_tgz_in (const char *dir)
 {
-  int err, r, len;
-  FILE *fp;
-  char *cmd;
-
-  if (!root_mounted || dir[0] != '/') {
-    cancel_receive ();
-    reply_with_error ("tar-in: root must be mounted and path must be absolute");
-    return -1;
-  }
-
-  /* "tar -C /sysroot%s -zxf -" but we have to quote the dir. */
-  len = 2 * strlen (dir) + sysroot_len + 32;
-  cmd = malloc (len);
-  if (!cmd) {
-    err = errno;
-    cancel_receive ();
-    errno = err;
-    reply_with_perror ("malloc");
-    return -1;
-  }
-  strcpy (cmd, "tar -C ");
-  strcat (cmd, sysroot);
-  shell_quote (cmd+15, len-15, dir);
-  strcat (cmd, " -zxf -");
-
-  fp = popen (cmd, "w");
-  if (fp == NULL) {
-    err = errno;
-    cancel_receive ();
-    errno = err;
-    reply_with_perror ("%s", cmd);
-    free (cmd);
-    return -1;
-  }
-  free (cmd);
-
-  r = receive_file (fwrite_cb, &fp);
-  if (r == -1) {		/* write error */
-    err = errno;
-    cancel_receive ();
-    errno = err;
-    reply_with_perror ("write: %s", dir);
-    pclose (fp);
-    return -1;
-  }
-  if (r == -2) {		/* cancellation from library */
-    pclose (fp);
-    /* Do NOT send any error. */
-    return -1;
-  }
-
-  if (pclose (fp) != 0) {
-    err = errno;
-    cancel_receive ();
-    errno = err;
-    reply_with_perror ("pclose: %s", dir);
-    return -1;
-  }
+  return do_tXz_in (dir, "z");
+}
 
-  return 0;
+/* Has one FileIn parameter. */
+int
+do_txz_in (const char *dir)
+{
+  return do_tXz_in (dir, "J");
 }
 
 /* Has one FileOut parameter. */
-int
-do_tgz_out (char *dir)
+static int
+do_tXz_out (const char *dir, const char *filter)
 {
-  int r, len;
+  int r;
   FILE *fp;
   char *cmd;
   char buf[GUESTFS_MAX_CHUNK_SIZE];
 
-  NEED_ROOT (-1);
-  ABS_PATH (dir, -1);
-
   /* "tar -C /sysroot%s -zcf - ." but we have to quote the dir. */
-  len = 2 * strlen (dir) + sysroot_len + 32;
-  cmd = malloc (len);
-  if (!cmd) {
-    reply_with_perror ("malloc");
+  if (asprintf_nowarn (&cmd, "tar -C %R -%scf - .", dir, filter) == -1) {
+    reply_with_perror ("asprintf");
     return -1;
   }
-  strcpy (cmd, "tar -C ");
-  strcat (cmd, sysroot);
-  shell_quote (cmd+15, len-15, dir);
-  strcat (cmd, " -zcf - .");
+
+  if (verbose)
+    fprintf (stderr, "%s\n", cmd);
 
   fp = popen (cmd, "r");
   if (fp == NULL) {
@@ -286,6 +213,29 @@ do_tgz_out (char *dir)
     return -1;
   }
 
-  send_file_end (0);		/* Normal end of file. */
+  if (send_file_end (0))	/* Normal end of file. */
+    return -1;
+
   return 0;
 }
+
+/* Has one FileOut parameter. */
+int
+do_tar_out (const char *dir)
+{
+  return do_tXz_out (dir, "");
+}
+
+/* Has one FileOut parameter. */
+int
+do_tgz_out (const char *dir)
+{
+  return do_tXz_out (dir, "z");
+}
+
+/* Has one FileOut parameter. */
+int
+do_txz_out (const char *dir)
+{
+  return do_tXz_out (dir, "J");
+}