1 /* libguestfs - the guestfsd daemon
2 * Copyright (C) 2009-2011 Red Hat Inc.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License along
15 * with this program; if not, write to the Free Software Foundation, Inc.,
16 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
19 #ifndef GUESTFSD_DAEMON_H
20 #define GUESTFSD_DAEMON_H
28 #include <rpc/types.h>
31 #include "guestfs_protocol.h"
33 /*-- in guestfsd.c --*/
36 extern int autosync_umount;
38 extern const char *sysroot;
39 extern size_t sysroot_len;
41 extern char *sysroot_path (const char *path);
43 extern int is_root_device (const char *device);
45 extern int xwrite (int sock, const void *buf, size_t len)
46 __attribute__((__warn_unused_result__));
47 extern int xread (int sock, void *buf, size_t len)
48 __attribute__((__warn_unused_result__));
50 extern int add_string (char ***argv, int *size, int *alloc, const char *str);
51 extern size_t count_strings (char *const *argv);
52 extern void sort_strings (char **argv, int len);
53 extern void free_strings (char **argv);
54 extern void free_stringslen (char **argv, int len);
56 extern int is_power_of_2 (unsigned long v);
58 #define command(out,err,name,...) commandf((out),(err),0,(name),__VA_ARGS__)
59 #define commandr(out,err,name,...) commandrf((out),(err),0,(name),__VA_ARGS__)
60 #define commandv(out,err,argv) commandvf((out),(err),0,(argv))
61 #define commandrv(out,err,argv) commandrvf((out),(err),0,(argv))
63 #define COMMAND_FLAG_FD_MASK (1024-1)
64 #define COMMAND_FLAG_FOLD_STDOUT_ON_STDERR 1024
65 #define COMMAND_FLAG_CHROOT_COPY_FILE_TO_STDIN 2048
67 extern int commandf (char **stdoutput, char **stderror, int flags,
68 const char *name, ...);
69 extern int commandrf (char **stdoutput, char **stderror, int flags,
70 const char *name, ...);
71 extern int commandvf (char **stdoutput, char **stderror, int flags,
72 char const *const *argv);
73 extern int commandrvf (char **stdoutput, char **stderror, int flags,
74 char const* const *argv);
76 extern char **split_lines (char *str);
78 extern void trim (char *str);
80 extern int device_name_translation (char *device);
82 extern int prog_exists (const char *prog);
84 extern void udev_settle (void);
86 /* This just stops gcc from giving a warning about our custom printf
87 * formatters %Q and %R. See guestfs(3)/EXTENDING LIBGUESTFS for more
91 asprintf_nowarn (char **strp, const char *fmt, ...)
97 r = vasprintf (strp, fmt, args);
102 /*-- in names.c (auto-generated) --*/
103 extern const char *function_names[];
108 extern uint64_t progress_hint;
109 extern uint64_t optargs_bitmask;
112 extern int is_root_mounted (void);
114 /*-- in stubs.c (auto-generated) --*/
115 extern void dispatch_incoming_message (XDR *);
116 extern guestfs_int_lvm_pv_list *parse_command_line_pvs (void);
117 extern guestfs_int_lvm_vg_list *parse_command_line_vgs (void);
118 extern guestfs_int_lvm_lv_list *parse_command_line_lvs (void);
120 /*-- in optgroups.c (auto-generated) --*/
122 const char *group; /* Name of the optional group. */
123 int (*available) (void); /* Function to test availability. */
125 extern struct optgroup optgroups[];
128 /* Use this as a replacement for sync(2). */
129 extern int sync_disks (void);
132 extern int e2prog (char *name); /* Massive hack for RHEL 5. */
135 extern int lv_canonical (const char *device, char **ret);
137 /*-- in lvm-filter.c --*/
138 extern void copy_lvm (void);
141 extern void main_loop (int sock) __attribute__((noreturn));
143 /* ordinary daemon functions use these to indicate errors
144 * NB: you don't need to prefix the string with the current command,
145 * it is added automatically by the client-side RPC stubs.
147 extern void reply_with_error (const char *fs, ...)
148 __attribute__((format (printf,1,2)));
149 extern void reply_with_perror_errno (int err, const char *fs, ...)
150 __attribute__((format (printf,2,3)));
151 #define reply_with_perror(...) reply_with_perror_errno(errno, __VA_ARGS__)
153 /* daemon functions that receive files (FileIn) should call
154 * receive_file for each FileIn parameter.
156 typedef int (*receive_cb) (void *opaque, const void *buf, size_t len);
157 extern int receive_file (receive_cb cb, void *opaque);
159 /* daemon functions that receive files (FileIn) can call this
160 * to cancel incoming transfers (eg. if there is a local error).
162 extern int cancel_receive (void);
164 /* daemon functions that return files (FileOut) should call
165 * reply, then send_file_* for each FileOut parameter.
166 * Note max write size if GUESTFS_MAX_CHUNK_SIZE.
168 extern int send_file_write (const void *buf, int len);
169 extern int send_file_end (int cancel);
171 /* only call this if there is a FileOut parameter */
172 extern void reply (xdrproc_t xdrp, char *ret);
174 /* Notify progress to caller. This function is self-rate-limiting so
175 * you can call it as often as necessary. Actions which call this
176 * should add 'Progress' note in generator.
178 extern void notify_progress (uint64_t position, uint64_t total);
180 /* Pulse mode progress messages.
182 * Call pulse_mode_start to start sending progress messages.
184 * Call pulse_mode_end along the ordinary exit path (ie. before a
185 * reply message is sent).
187 * Call pulse_mode_cancel along all error paths *before* any reply is
188 * sent. pulse_mode_cancel does not modify errno, so it is safe to
189 * call it before reply_with_perror.
191 * Pulse mode and ordinary notify_progress must not be mixed.
193 extern void pulse_mode_start (void);
194 extern void pulse_mode_end (void);
195 extern void pulse_mode_cancel (void);
197 /* Return true iff the buffer is all zero bytes.
199 * Note that gcc is smart enough to optimize this properly:
200 * http://stackoverflow.com/questions/1493936/faster-means-of-checking-for-an-empty-buffer-in-c/1493989#1493989
203 is_zero (const char *buffer, size_t size)
207 for (i = 0; i < size; ++i) {
215 /* Helper for building up short lists of arguments. Your code has to
216 * define MAX_ARGS to a suitable value.
218 #define ADD_ARG(argv,i,v) \
220 if ((i) >= MAX_ARGS) { \
221 fprintf (stderr, "%s: %d: internal error: exceeded MAX_ARGS (%zu) when constructing the command line\n", __FILE__, __LINE__, (size_t) MAX_ARGS); \
224 (argv)[(i)++] = (v); \
227 /* Helper for functions that need a root filesystem mounted.
228 * NB. Cannot be used for FileIn functions.
230 #define NEED_ROOT(cancel_stmt,fail_stmt) \
232 if (!is_root_mounted ()) { \
234 reply_with_error ("%s: you must call 'mount' first to mount the root filesystem", __func__); \
240 /* Helper for functions that need an argument ("path") that is absolute.
241 * NB. Cannot be used for FileIn functions.
243 #define ABS_PATH(path,cancel_stmt,fail_stmt) \
245 if ((path)[0] != '/') { \
247 reply_with_error ("%s: path must start with a / character", __func__); \
252 /* All functions that need an argument that is a device or partition name
253 * must call this macro. It checks that the device exists and does
254 * device name translation (described in the guestfs(3) manpage).
255 * Note that the "path" argument may be modified.
257 * NB. Cannot be used for FileIn functions.
259 #define RESOLVE_DEVICE(path,cancel_stmt,fail_stmt) \
261 if (STRNEQLEN ((path), "/dev/", 5)) { \
263 reply_with_error ("%s: %s: expecting a device name", __func__, (path)); \
266 if (is_root_device (path)) \
267 reply_with_error ("%s: %s: device not found", __func__, path); \
268 if (device_name_translation ((path)) == -1) { \
272 reply_with_perror ("%s: %s", __func__, path); \
277 /* Helper for functions which need either an absolute path in the
278 * mounted filesystem, OR a /dev/ device which exists.
280 * NB. Cannot be used for FileIn functions.
282 * NB #2: Functions which mix filenames and device paths should be
283 * avoided, and existing functions should be deprecated. This is
284 * because we intend in future to make device parameters a distinct
285 * type from filenames.
287 #define REQUIRE_ROOT_OR_RESOLVE_DEVICE(path,cancel_stmt,fail_stmt) \
289 if (STREQLEN ((path), "/dev/", 5)) \
290 RESOLVE_DEVICE ((path), cancel_stmt, fail_stmt); \
292 NEED_ROOT (cancel_stmt, fail_stmt); \
293 ABS_PATH ((path), cancel_stmt, fail_stmt); \
298 * (1) You must match CHROOT_IN and CHROOT_OUT even along error paths.
299 * (2) You must not change directory! cwd must always be "/", otherwise
300 * we can't escape our own chroot.
301 * (3) All paths specified must be absolute.
302 * (4) Neither macro affects errno.
306 if (sysroot_len > 0) { \
307 int __old_errno = errno; \
308 if (chroot (sysroot) == -1) \
309 perror ("CHROOT_IN: sysroot"); \
310 errno = __old_errno; \
315 if (sysroot_len > 0) { \
316 int __old_errno = errno; \
317 if (chroot (".") == -1) \
318 perror ("CHROOT_OUT: ."); \
319 errno = __old_errno; \
323 /* Marks functions which are not implemented.
324 * NB. Cannot be used for FileIn functions.
326 #define XXX_NOT_IMPL(errcode) \
328 reply_with_error ("%s: function not implemented", __func__); \
333 /* Marks functions which are not available.
334 * NB. Cannot be used for FileIn functions.
336 #define NOT_AVAILABLE(errcode) \
338 reply_with_error ("%s: function not available", __func__); \
343 #ifndef __attribute__
344 # if __GNUC__ < 2 || (__GNUC__ == 2 && __GNUC_MINOR__ < 8)
345 # define __attribute__(x) /* empty */
349 #ifndef ATTRIBUTE_UNUSED
350 # define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
353 #define STREQ(a,b) (strcmp((a),(b)) == 0)
354 #define STRCASEEQ(a,b) (strcasecmp((a),(b)) == 0)
355 #define STRNEQ(a,b) (strcmp((a),(b)) != 0)
356 #define STRCASENEQ(a,b) (strcasecmp((a),(b)) != 0)
357 #define STREQLEN(a,b,n) (strncmp((a),(b),(n)) == 0)
358 #define STRCASEEQLEN(a,b,n) (strncasecmp((a),(b),(n)) == 0)
359 #define STRNEQLEN(a,b,n) (strncmp((a),(b),(n)) != 0)
360 #define STRCASENEQLEN(a,b,n) (strncasecmp((a),(b),(n)) != 0)
361 #define STRPREFIX(a,b) (strncmp((a),(b),strlen((b))) == 0)
363 #endif /* GUESTFSD_DAEMON_H */