From 42c89f2e6bd956f738080b5aec53b7520f4f96da Mon Sep 17 00:00:00 2001 From: Richard Jones Date: Mon, 19 Oct 2009 17:44:16 +0100 Subject: [PATCH] New API: find0 (unlimited version of find) This adds a new API call guestfs_find0, which is like guestfs_find but mainly doesn't suffer from the protocol limit of the earlier command. The earlier command is not deprecated because it is still very useful. guestfs_find0 uses a FileOut parameter and writes the results to an external file. The filenames in the output are separated by ASCII NUL characters (so a bit like "find -print0"). There is also the addition of a regression test for this command. --- daemon/find.c | 99 +++++++++++++++++++++++++++++++++++++++++++++++ regressions/Makefile.am | 1 + regressions/test-find0.sh | 39 +++++++++++++++++++ src/MAX_PROC_NR | 2 +- src/generator.ml | 37 +++++++++++++++++- 5 files changed, 176 insertions(+), 2 deletions(-) create mode 100755 regressions/test-find0.sh diff --git a/daemon/find.c b/daemon/find.c index 2147c57..b659eb6 100644 --- a/daemon/find.c +++ b/daemon/find.c @@ -129,3 +129,102 @@ do_find (const char *dir) return res; /* caller frees */ } + +/* The code below assumes each path returned can fit into a protocol + * chunk. If this turns out not to be true at some point in the + * future then we'll need to modify the code a bit to handle it. + */ +#if PATH_MAX > GUESTFS_MAX_CHUNK_SIZE +#error "PATH_MAX > GUESTFS_MAX_CHUNK_SIZE" +#endif + +/* Has one FileOut parameter. */ +int +do_find0 (const char *dir) +{ + struct stat statbuf; + int r; + FILE *fp; + char *cmd; + char *sysrootdir; + size_t sysrootdirlen, len; + char str[GUESTFS_MAX_CHUNK_SIZE]; + + sysrootdir = sysroot_path (dir); + if (!sysrootdir) { + reply_with_perror ("malloc"); + return -1; + } + + r = stat (sysrootdir, &statbuf); + if (r == -1) { + reply_with_perror ("%s", dir); + free (sysrootdir); + return -1; + } + if (!S_ISDIR (statbuf.st_mode)) { + reply_with_error ("%s: not a directory", dir); + free (sysrootdir); + return -1; + } + + sysrootdirlen = strlen (sysrootdir); + + if (asprintf_nowarn (&cmd, "find %Q -print0", sysrootdir) == -1) { + reply_with_perror ("asprintf"); + free (sysrootdir); + return -1; + } + free (sysrootdir); + + if (verbose) + fprintf (stderr, "%s\n", cmd); + + 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 = input_to_nul (fp, str, GUESTFS_MAX_CHUNK_SIZE)) > 0) { + if (verbose) + printf ("find0 string: %s\n", str); + + len = strlen (str); + if (len <= sysrootdirlen) + continue; + + /* Remove the directory part of the path before sending it. */ + if (send_file_write (str + sysrootdirlen, r - sysrootdirlen) < 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; + } + + if (send_file_end (0)) /* Normal end of file. */ + return -1; + + return 0; +} + diff --git a/regressions/Makefile.am b/regressions/Makefile.am index 9112b94..058b60d 100644 --- a/regressions/Makefile.am +++ b/regressions/Makefile.am @@ -26,6 +26,7 @@ TESTS = \ rhbz503169c13.sh \ test-cancellation-download-librarycancels.sh \ test-cancellation-upload-daemoncancels.sh \ + test-find0.sh \ test-noexec-stack.pl \ test-qemudie-killsub.sh \ test-qemudie-midcommand.sh \ diff --git a/regressions/test-find0.sh b/regressions/test-find0.sh new file mode 100755 index 0000000..4849b64 --- /dev/null +++ b/regressions/test-find0.sh @@ -0,0 +1,39 @@ +#!/bin/sh - +# libguestfs +# Copyright (C) 2009 Red Hat Inc. +# +# This program is free software; you can redistribute it and/or modify +# it under the terms of the GNU General Public License as published by +# the Free Software Foundation; either version 2 of the License, or +# (at your option) any later version. +# +# This program is distributed in the hope that it will be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write to the Free Software +# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + +# Test find0 call. + +set -e + +rm -f test.out + +../fish/guestfish <<'EOF' +add-ro ../images/test.iso +run +mount-ro /dev/sda / +find0 / test.out +EOF + +n=$(tr '\0' '\n' < test.out | grep '^known-[1-5]' | wc -l) +[ "$n" = 5 ] || { + echo find0: Invalid list of files + tr '\0' '\n' < test.out + exit 1 +} + +rm -f test.out diff --git a/src/MAX_PROC_NR b/src/MAX_PROC_NR index 6bb2f98..0f11735 100644 --- a/src/MAX_PROC_NR +++ b/src/MAX_PROC_NR @@ -1 +1 @@ -195 +196 diff --git a/src/generator.ml b/src/generator.ml index 74890b4..cea5178 100755 --- a/src/generator.ml +++ b/src/generator.ml @@ -2525,7 +2525,9 @@ then the returned list from C C would be If C is not a directory, then this command returns an error. -The returned list is sorted."); +The returned list is sorted. + +See also C."); ("e2fsck_f", (RErr, [Device "device"]), 108, [], [], (* lvresize tests this *) @@ -3610,6 +3612,39 @@ You can use this command to test the connection through to the daemon. See also C."); + ("find0", (RErr, [Pathname "directory"; FileOut "files"]), 196, [], + [], (* There is a regression test for this. *) + "find all files and directories, returning NUL-separated list", + "\ +This command lists out all files and directories, recursively, +starting at C, placing the resulting list in the +external file called C. + +This command works the same way as C with the +following exceptions: + +=over 4 + +=item * + +The resulting list is written to an external file. + +=item * + +Items (filenames) in the result are separated +by C<\\0> characters. See L option I<-print0>. + +=item * + +This command is not limited in the number of names that it +can return. + +=item * + +The result list is not sorted. + +=back"); + ] let all_functions = non_daemon_functions @ daemon_functions -- 1.8.3.1