unsigned int bus, unsigned int dev,
unsigned int func, unsigned int vdevfn);
+/*
+ * Functions for allowing users of libxl to store private data
+ * relating to a domain. The data is an opaque sequence of bytes and
+ * is not interpreted or used by libxl.
+ *
+ * Data is indexed by the userdata userid, which is a short printable
+ * ASCII string. The following list is a registry of userdata userids
+ * (the registry may be updated by posting a patch to xen-devel):
+ *
+ * userid Data contents
+ * "xl" domain config file in xl format, Unix line endings
+ *
+ * libxl does not enforce the registration of userdata userids or the
+ * semantics of the data. For specifications of the data formats
+ * see the code or documentation for the libxl caller in question.
+ */
+int libxl_userdata_store(struct libxl_ctx *ctx, uint32_t domid,
+ const char *userdata_userid,
+ const uint8_t *data, int datalen);
+ /* If datalen==0, data is not used and the user data for
+ * that domain and userdata_userid is deleted. */
+int libxl_userdata_retrieve(struct libxl_ctx *ctx, uint32_t domid,
+ const char *userdata_userid,
+ uint8_t **data_r, int *datalen_r);
+ /* On successful return, *data_r is from malloc.
+ * If there is no data for that domain and userdata_userid,
+ * *data_r and *datalen_r will be set to 0.
+ * data_r and datalen_r may be 0.
+ * On error return, *data_r and *datalen_r are undefined.
+ */
+
typedef enum {
POWER_BUTTON,
SLEEP_BUTTON
#include "libxl_osdeps.h"
#include <stdio.h>
+#include <assert.h>
+#include <glob.h>
#include <inttypes.h>
#include <string.h>
#include <sys/time.h> /* for struct timeval */
if (!s) XL_LOG(ctx, XL_LOG_ERROR, "cannot allocate for uuid");
return s;
}
+
+static const char *userdata_path(struct libxl_ctx *ctx, uint32_t domid,
+ const char *userdata_userid,
+ const char *wh) {
+ char *path, *uuid_string;
+ struct libxl_dominfo info;
+ int rc;
+
+ rc = libxl_domain_info(ctx, &info, domid);
+ if (rc) {
+ XL_LOG_ERRNO(ctx, XL_LOG_ERROR, "unable to find domain info"
+ " for domain %l"PRIu32, domid);
+ return 0;
+ }
+ uuid_string = string_of_uuid(ctx, info.uuid);
+
+ path = libxl_sprintf(ctx, "/var/lib/xen/"
+ "userdata-%s.%s.%s",
+ wh, uuid_string, userdata_userid);
+ if (!path)
+ XL_LOG_ERRNO(ctx, XL_LOG_ERROR, "unable to allocate for"
+ " userdata path");
+ return path;
+}
+
+static int userdata_delete(struct libxl_ctx *ctx, const char *path) {
+ int r;
+ r = unlink(path);
+ if (r) {
+ XL_LOG_ERRNO(ctx, XL_LOG_ERROR, "remove failed for %s", path);
+ return errno;
+ }
+ return 0;
+}
+
+void libxl__userdata_destroyall(struct libxl_ctx *ctx, uint32_t domid) {
+ const char *pattern;
+ glob_t gl;
+ int r, i;
+
+ pattern = userdata_path(ctx, domid, "*", "?");
+ if (!pattern) return;
+
+ gl.gl_pathc = 0;
+ gl.gl_pathv = 0;
+ gl.gl_offs = 0;
+ r = glob(pattern, GLOB_ERR|GLOB_NOSORT|GLOB_MARK, 0, &gl);
+ if (r == GLOB_NOMATCH) return;
+ if (r) XL_LOG_ERRNO(ctx, XL_LOG_ERROR, "glob failed for %s", pattern);
+
+ for (i=0; i<gl.gl_pathc; i++) {
+ userdata_delete(ctx, gl.gl_pathv[i]);
+ }
+ globfree(&gl);
+}
+
+int libxl_userdata_store(struct libxl_ctx *ctx, uint32_t domid,
+ const char *userdata_userid,
+ const uint8_t *data, int datalen) {
+ const char *filename;
+ const char *newfilename;
+ int e;
+ int fd = -1;
+ FILE *f = 0;
+ size_t rs;
+
+ filename = userdata_path(ctx, domid, userdata_userid, "d");
+ if (!filename) return ENOMEM;
+
+ if (!datalen)
+ return userdata_delete(ctx, filename);
+
+ newfilename = userdata_path(ctx, domid, userdata_userid, "n");
+ if (!newfilename) return ENOMEM;
+
+ fd= open(newfilename, O_RDWR|O_CREAT|O_TRUNC, 0600);
+ if (fd<0) goto xe;
+
+ f= fdopen(fd, "wb");
+ if (!f) goto xe;
+ fd = -1;
+
+ rs = fwrite(data, 1, datalen, f);
+ if (rs != datalen) { assert(ferror(f)); goto xe; }
+
+ if (fclose(f)) goto xe;
+ f = 0;
+
+ if (rename(newfilename,filename)) goto xe;
+
+ return 0;
+
+ xe:
+ e = errno;
+ if (f) fclose(f);
+ if (fd>=0) close(fd);
+
+ XL_LOG_ERRNO(ctx, XL_LOG_ERROR, "cannot write %s for %s",
+ newfilename, filename);
+ return e;
+}
+
+int libxl_userdata_retrieve(struct libxl_ctx *ctx, uint32_t domid,
+ const char *userdata_userid,
+ uint8_t **data_r, int *datalen_r) {
+ const char *filename;
+ int e;
+ int datalen = 0;
+ void *data = 0;
+
+ filename = userdata_path(ctx, domid, userdata_userid, "d");
+ if (!filename) return ENOMEM;
+
+ e = libxl_read_file_contents(ctx, filename, data_r ? &data : 0, &datalen);
+
+ if (!e && !datalen) {
+ XL_LOG(ctx, XL_LOG_ERROR, "userdata file %s is empty", filename);
+ if (data_r) assert(!*data_r);
+ return EPROTO;
+ }
+
+ if (data_r) *data_r = data;
+ if (datalen_r) *datalen_r = datalen;
+ return 0;
+}
projects / xen.git / commitdiff