1 /*
2 * Copyright (C) 2009 Citrix Ltd.
3 * Author Vincent Hanquez <vincent.hanquez@eu.citrix.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU Lesser General Public License as published
7 * by the Free Software Foundation; version 2.1 only. with the special
8 * exception on linking described in file LICENSE.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU Lesser General Public License for more details.
14 */
15
16 #include "libxl_osdeps.h" /* must come before any other headers */
17
18 #include "libxl_internal.h"
19
libxl__xs_kvs_of_flexarray(libxl__gc * gc,flexarray_t * array)20 char **libxl__xs_kvs_of_flexarray(libxl__gc *gc, flexarray_t *array)
21 {
22 char **kvs;
23 int i, length;
24
25 if (!array)
26 return NULL;
27
28 length = array->count;
29 if (!length)
30 return NULL;
31
32 kvs = libxl__calloc(gc, length + 2, sizeof(char *));
33 if (kvs) {
34 for (i = 0; i < length; i += 2) {
35 void *ptr;
36
37 flexarray_get(array, i, &ptr);
38 kvs[i] = (char *) ptr;
39 flexarray_get(array, i + 1, &ptr);
40 kvs[i + 1] = (char *) ptr;
41 }
42 kvs[i] = NULL;
43 kvs[i + 1] = NULL;
44 }
45 return kvs;
46 }
47
libxl__xs_writev_perms(libxl__gc * gc,xs_transaction_t t,const char * dir,char * kvs[],struct xs_permissions * perms,unsigned int num_perms)48 int libxl__xs_writev_perms(libxl__gc *gc, xs_transaction_t t,
49 const char *dir, char *kvs[],
50 struct xs_permissions *perms,
51 unsigned int num_perms)
52 {
53 libxl_ctx *ctx = libxl__gc_owner(gc);
54 char *path;
55 int i;
56
57 if (!kvs)
58 return 0;
59
60 for (i = 0; kvs[i] != NULL; i += 2) {
61 path = GCSPRINTF("%s/%s", dir, kvs[i]);
62 if (path && kvs[i + 1]) {
63 int length = strlen(kvs[i + 1]);
64 xs_write(ctx->xsh, t, path, kvs[i + 1], length);
65 if (perms)
66 xs_set_permissions(ctx->xsh, t, path, perms, num_perms);
67 }
68 }
69 return 0;
70 }
71
libxl__xs_writev(libxl__gc * gc,xs_transaction_t t,const char * dir,char * kvs[])72 int libxl__xs_writev(libxl__gc *gc, xs_transaction_t t,
73 const char *dir, char *kvs[])
74 {
75 return libxl__xs_writev_perms(gc, t, dir, kvs, NULL, 0);
76 }
77
libxl__xs_writev_atonce(libxl__gc * gc,const char * dir,char * kvs[])78 int libxl__xs_writev_atonce(libxl__gc *gc,
79 const char *dir, char *kvs[])
80 {
81 int rc;
82 xs_transaction_t t = XBT_NULL;
83
84 for (;;) {
85 rc = libxl__xs_transaction_start(gc, &t);
86 if (rc) goto out;
87
88 rc = libxl__xs_writev(gc, t, dir, kvs);
89 if (rc) goto out;
90
91 rc = libxl__xs_transaction_commit(gc, &t);
92 if (!rc) break;
93 if (rc<0) goto out;
94 }
95
96 out:
97 libxl__xs_transaction_abort(gc, &t);
98
99 return rc;
100
101 }
102
libxl__xs_vprintf(libxl__gc * gc,xs_transaction_t t,const char * path,const char * fmt,va_list ap)103 int libxl__xs_vprintf(libxl__gc *gc, xs_transaction_t t,
104 const char *path, const char *fmt, va_list ap)
105 {
106 libxl_ctx *ctx = libxl__gc_owner(gc);
107 char *s;
108 bool ok;
109
110 s = libxl__vsprintf(gc, fmt, ap);
111
112 ok = xs_write(ctx->xsh, t, path, s, strlen(s));
113 if (!ok) {
114 LOGE(ERROR, "xenstore write failed: `%s' = `%s'", path, s);
115 return ERROR_FAIL;
116 }
117
118 return 0;
119 }
120
libxl__xs_printf(libxl__gc * gc,xs_transaction_t t,const char * path,const char * fmt,...)121 int libxl__xs_printf(libxl__gc *gc, xs_transaction_t t,
122 const char *path, const char *fmt, ...)
123 {
124 va_list ap;
125 int rc;
126
127 va_start(ap, fmt);
128 rc = libxl__xs_vprintf(gc, t, path, fmt, ap);
129 va_end(ap);
130
131 return rc;
132 }
133
libxl__xs_read(libxl__gc * gc,xs_transaction_t t,const char * path)134 char * libxl__xs_read(libxl__gc *gc, xs_transaction_t t, const char *path)
135 {
136 libxl_ctx *ctx = libxl__gc_owner(gc);
137 char *ptr;
138
139 ptr = xs_read(ctx->xsh, t, path, NULL);
140 libxl__ptr_add(gc, ptr);
141 return ptr;
142 }
143
libxl__xs_get_dompath(libxl__gc * gc,uint32_t domid)144 char *libxl__xs_get_dompath(libxl__gc *gc, uint32_t domid)
145 {
146 libxl_ctx *ctx = libxl__gc_owner(gc);
147 char *s = xs_get_domain_path(ctx->xsh, domid);
148 if (!s) {
149 LOGED(ERROR, domid, "Failed to get dompath");
150 return NULL;
151 }
152 libxl__ptr_add(gc, s);
153 return s;
154 }
155
libxl__xs_directory(libxl__gc * gc,xs_transaction_t t,const char * path,unsigned int * nb)156 char **libxl__xs_directory(libxl__gc *gc, xs_transaction_t t,
157 const char *path, unsigned int *nb)
158 {
159 libxl_ctx *ctx = libxl__gc_owner(gc);
160 char **ret = NULL;
161 ret = xs_directory(ctx->xsh, t, path, nb);
162 libxl__ptr_add(gc, ret);
163 return ret;
164 }
165
libxl__xs_mknod(libxl__gc * gc,xs_transaction_t t,const char * path,struct xs_permissions * perms,unsigned int num_perms)166 int libxl__xs_mknod(libxl__gc *gc, xs_transaction_t t,
167 const char *path, struct xs_permissions *perms,
168 unsigned int num_perms)
169 {
170 libxl_ctx *ctx = libxl__gc_owner(gc);
171 bool ok;
172
173 ok = xs_write(ctx->xsh, t, path, "", 0);
174 if (!ok) {
175 LOGE(ERROR, "xenstore write failed: `%s' = ''", path);
176 return ERROR_FAIL;
177 }
178
179 ok = xs_set_permissions(ctx->xsh, t, path, perms, num_perms);
180 if (!ok) {
181 LOGE(ERROR, "xenstore set permissions failed on `%s'", path);
182 return ERROR_FAIL;
183 }
184
185 return 0;
186 }
187
libxl__xs_libxl_path(libxl__gc * gc,uint32_t domid)188 char *libxl__xs_libxl_path(libxl__gc *gc, uint32_t domid)
189 {
190 char *s = GCSPRINTF("/libxl/%i", domid);
191 if (!s)
192 LOGD(ERROR, domid, "cannot allocate create paths");
193 return s;
194 }
195
libxl__xs_read_mandatory(libxl__gc * gc,xs_transaction_t t,const char * path,const char ** result_out)196 int libxl__xs_read_mandatory(libxl__gc *gc, xs_transaction_t t,
197 const char *path, const char **result_out)
198 {
199 char *result = libxl__xs_read(gc, t, path);
200 if (!result) {
201 LOGE(ERROR, "xenstore read failed: `%s'", path);
202 return ERROR_FAIL;
203 }
204 *result_out = result;
205 return 0;
206 }
207
libxl__xs_read_checked(libxl__gc * gc,xs_transaction_t t,const char * path,const char ** result_out)208 int libxl__xs_read_checked(libxl__gc *gc, xs_transaction_t t,
209 const char *path, const char **result_out)
210 {
211 char *result = libxl__xs_read(gc, t, path);
212 if (!result) {
213 if (errno != ENOENT) {
214 LOGE(ERROR, "xenstore read failed: `%s'", path);
215 return ERROR_FAIL;
216 }
217 }
218 *result_out = result;
219 return 0;
220 }
221
libxl__xs_write_checked(libxl__gc * gc,xs_transaction_t t,const char * path,const char * string)222 int libxl__xs_write_checked(libxl__gc *gc, xs_transaction_t t,
223 const char *path, const char *string)
224 {
225 size_t length = strlen(string);
226 if (!xs_write(CTX->xsh, t, path, string, length)) {
227 LOGE(ERROR, "xenstore write failed: `%s' = `%s'", path, string);
228 return ERROR_FAIL;
229 }
230 return 0;
231 }
232
libxl__xs_rm_checked(libxl__gc * gc,xs_transaction_t t,const char * path)233 int libxl__xs_rm_checked(libxl__gc *gc, xs_transaction_t t, const char *path)
234 {
235 if (!xs_rm(CTX->xsh, t, path)) {
236 if (errno == ENOENT)
237 return 0;
238
239 LOGE(ERROR, "xenstore rm failed: `%s'", path);
240 return ERROR_FAIL;
241 }
242 return 0;
243 }
244
libxl__xs_transaction_start(libxl__gc * gc,xs_transaction_t * t)245 int libxl__xs_transaction_start(libxl__gc *gc, xs_transaction_t *t)
246 {
247 assert(!*t);
248 *t = xs_transaction_start(CTX->xsh);
249 if (!*t) {
250 LOGE(ERROR, "could not create xenstore transaction");
251 return ERROR_FAIL;
252 }
253 return 0;
254 }
255
libxl__xs_transaction_commit(libxl__gc * gc,xs_transaction_t * t)256 int libxl__xs_transaction_commit(libxl__gc *gc, xs_transaction_t *t)
257 {
258 assert(*t);
259
260 if (!xs_transaction_end(CTX->xsh, *t, 0)) {
261 *t = 0;
262 if (errno == EAGAIN)
263 return +1;
264
265 LOGE(ERROR, "could not commit xenstore transaction");
266 return ERROR_FAIL;
267 }
268
269 *t = 0;
270 return 0;
271 }
272
libxl__xs_transaction_abort(libxl__gc * gc,xs_transaction_t * t)273 void libxl__xs_transaction_abort(libxl__gc *gc, xs_transaction_t *t)
274 {
275 if (!*t)
276 return;
277
278 if (!xs_transaction_end(CTX->xsh, *t, 1))
279 LOGE(ERROR, "could not abort xenstore transaction");
280
281 *t = 0;
282 }
283
libxl__xs_path_cleanup(libxl__gc * gc,xs_transaction_t t,const char * user_path)284 int libxl__xs_path_cleanup(libxl__gc *gc, xs_transaction_t t,
285 const char *user_path)
286 {
287 unsigned int nb = 0;
288 char *path, *last, *val;
289 int rc;
290
291 /* A path and transaction must be provided by the caller */
292 assert(user_path && t);
293
294 path = libxl__strdup(gc, user_path);
295 if (!xs_rm(CTX->xsh, t, path)) {
296 if (errno != ENOENT)
297 LOGE(DEBUG, "unable to remove path %s", path);
298 rc = ERROR_FAIL;
299 goto out;
300 }
301
302 for (last = strrchr(path, '/'); last != NULL; last = strrchr(path, '/')) {
303 *last = '\0';
304
305 if (!strlen(path)) break;
306
307 val = libxl__xs_read(gc, t, path);
308 if (!val || strlen(val) != 0) break;
309
310 if (!libxl__xs_directory(gc, t, path, &nb) || nb != 0) break;
311
312 if (!xs_rm(CTX->xsh, t, path)) {
313 if (errno != ENOENT)
314 LOGE(DEBUG, "unable to remove path %s", path);
315 rc = ERROR_FAIL;
316 goto out;
317 }
318 }
319 rc = 0;
320
321 out:
322 return rc;
323 }
324
325 /*
326 * Local variables:
327 * mode: C
328 * c-basic-offset: 4
329 * indent-tabs-mode: nil
330 * End:
331 */
332