Implement 'strings' and 'hexdump' commands.

daemon/Makefile.am

@@ -37,12 +37,14 @@ guestfsd_SOURCES = \
 	fsck.c \
 	grub.c \
 	guestfsd.c \
+	hexdump.c \
 	ls.c \
 	lvm.c \
 	mount.c \
 	pingdaemon.c \
 	proto.c \
 	stat.c \
+	strings.c \
 	stubs.c \
 	sync.c \
 	tar.c \

daemon/hexdump.c

@@ -0,0 +1,60 @@
+/* libguestfs - the guestfsd daemon
+ * 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.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "daemon.h"
+#include "actions.h"
+
+char *
+do_hexdump (const char *path)
+{
+  int len;
+  char *buf;
+  int r;
+  char *out, *err;
+
+  NEED_ROOT (NULL);
+  ABS_PATH (path, NULL);
+
+  len = strlen (path) + 9;
+  buf = malloc (len);
+  if (!buf) {
+    reply_with_perror ("malloc");
+    return NULL;
+  }
+
+  snprintf (buf, len, "/sysroot%s", path);
+
+  r = command (&out, &err, "hexdump", "-C", buf, NULL);
+  free (buf);
+  if (r == -1) {
+    reply_with_error ("hexdump: %s: %s", path, err);
+    free (err);
+    free (out);
+    return NULL;
+  }
+
+  free (err);
+
+  return out;			/* caller frees */
+}

daemon/strings.c

@@ -0,0 +1,91 @@
+/* libguestfs - the guestfsd daemon
+ * 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.
+ */
+
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "daemon.h"
+#include "actions.h"
+
+char **
+do_strings_e (const char *encoding, const char *path)
+{
+  int len;
+  char *buf;
+  int r;
+  char *out, *err;
+  char **lines = NULL;
+  int size = 0, alloc = 0;
+  char *p, *pend;
+
+  NEED_ROOT (NULL);
+  ABS_PATH (path, NULL);
+
+  len = strlen (path) + 9;
+  buf = malloc (len);
+  if (!buf) {
+    reply_with_perror ("malloc");
+    return NULL;
+  }
+
+  snprintf (buf, len, "/sysroot%s", path);
+
+  r = command (&out, &err, "strings", "-e", encoding, buf, NULL);
+  free (buf);
+  if (r == -1) {
+    reply_with_error ("strings: %s: %s", path, err);
+    free (err);
+    free (out);
+    return NULL;
+  }
+
+  free (err);
+
+  /* Now convert the output to a list of lines. */
+  p = out;
+  while (p && *p) {
+    pend = strchr (p, '\n');
+    if (pend) {
+      *pend = '\0';
+      pend++;
+    }
+
+    if (add_string (&lines, &size, &alloc, p) == -1) {
+      free (out);
+      return NULL;
+    }
+
+    p = pend;
+  }
+
+  free (out);
+
+  if (add_string (&lines, &size, &alloc, NULL) == -1)
+    return NULL;
+
+  return lines;			/* Caller frees. */
+}
+
+char **
+do_strings (const char *path)
+{
+  return do_strings_e ("s", path);
+}

src/generator.ml

@@ -1807,6 +1807,43 @@ true if their content is exactly equal, or false otherwise.
 
 The external L<cmp(1)> program is used for the comparison.");
 
+  ("strings", (RStringList "stringsout", [String "path"]), 94, [ProtocolLimitWarning],
+   [InitBasicFS, TestOutputList (
+      [["write_file"; "/new"; "hello\nworld\n"; "0"];
+       ["strings"; "/new"]], ["hello"; "world"])],
+   "print the printable strings in a file",
+   "\
+This runs the L<strings(1)> command on a file and returns
+the list of printable strings found.");
+
+  ("strings_e", (RStringList "stringsout", [String "encoding"; String "path"]), 95, [ProtocolLimitWarning],
+   [InitBasicFS, TestOutputList (
+      [["write_file"; "/new"; "hello\nworld\n"; "0"];
+       ["strings_e"; "b"; "/new"]], []);
+    (*InitBasicFS, TestOutputList (
+      [["write_file"; "/new"; "\000h\000e\000l\000l\000o\000\n\000w\000o\000r\000l\000d\000\n"; "24"];
+       ["strings_e"; "b"; "/new"]], ["hello"; "world"])*)],
+   "print the printable strings in a file",
+   "\
+This is like the C<guestfs_strings> command, but allows you to
+specify the encoding.
+
+See the L<strings(1)> manpage for the full list of encodings.
+
+Commonly useful encodings are C<l> (lower case L) which will
+show strings inside Windows/x86 files.
+
+The returned strings are transcoded to UTF-8.");
+
+  ("hexdump", (RString "dump", [String "path"]), 96, [ProtocolLimitWarning],
+   [InitBasicFS, TestOutput (
+      [["write_file"; "/new"; "hello\nworld\n"; "12"];
+       ["hexdump"; "/new"]], "00000000  68 65 6c 6c 6f 0a 77 6f  72 6c 64 0a              |hello.world.|\n0000000c\n")],
+   "dump a file in hexadecimal",
+   "\
+This runs C<hexdump -C> on the given C<path>.  The result is
+the human-readable, canonical hex dump of the file.");
+
 ]
 
 let all_functions = non_daemon_functions @ daemon_functions