Changeset 0499235 in mainline for uspace/lib/c

Timestamp:

2012-03-02T17:20:23Z (13 years ago)

Author:

Martin Decky <martin@…>

Branches:

lfn, master, serial, ticket/834-toolchain-update, topic/msim-upgrade, topic/simplify-dev-export

Children:

5608deba, 98cb0495, c30a015

Parents:

3113d47

Message:

add basic support for encoding name/value properties in sysinfo

Location:

uspace/lib/c

Files:

• generic/sysinfo.c (modified) (3 diffs)
• include/sysinfo.h (modified) (1 diff)

uspace/lib/c/generic/sysinfo.c

@@ -134 +134 @@
 /** Get sysinfo binary data size
  *
- * @param path  Sysinfo path.
- * @param value Pointer to store the binary data size.
+ * @param path Sysinfo path.
+ * @param size Pointer to store the binary data size.
  *
  * @return EOK if the value was successfully read and
@@ -149 +149 @@
 /** Get sysinfo binary data
  *
- * @param path  Sysinfo path.
- * @param value Pointer to store the binary data size.
+ * @param path Sysinfo path.
+ * @param size Pointer to store the binary data size.
  *
  * @return Binary data read from sysinfo or NULL if the
@@ -198 +198 @@
 }
 
+/** Get sysinfo property
+ *
+ * @param path Sysinfo path.
+ * @param name Property name.
+ * @param size Pointer to store the binary data size.
+ *
+ * @return Property value read from sysinfo or NULL if the
+ *         sysinfo item value type is not binary data.
+ *         The returned non-NULL pointer should be
+ *         freed by free().
+ *
+ */
+void *sysinfo_get_property(const char *path, const char *name, size_t *size)
+{
+        size_t total_size;
+        void *data = sysinfo_get_data(path, &total_size);
+        if ((data == NULL) || (total_size == 0)) {
+                *size = 0;
+                return NULL;
+        }
+        
+        size_t pos = 0;
+        while (pos < total_size) {
+                /* Process each property with sanity checks */
+                size_t cur_size = str_nsize(data + pos, total_size - pos);
+                if (((char *) data)[pos + cur_size] != 0)
+                        break;
+                
+                bool found = (str_cmp(data + pos, name) == 0);
+                
+                pos += cur_size + 1;
+                if (pos >= total_size)
+                        break;
+                
+                /* Process value size */
+                size_t value_size;
+                memcpy(&value_size, data + pos, sizeof(value_size));
+                
+                pos += sizeof(value_size);
+                if ((pos >= total_size) || (pos + value_size > total_size))
+                        break;
+                
+                if (found) {
+                        void *value = malloc(value_size);
+                        if (value == NULL)
+                                break;
+                        
+                        memcpy(value, data + pos, value_size);
+                        free(data);
+                        
+                        *size = value_size;
+                        return value;
+                }
+                
+                pos += value_size;
+        }
+        
+        free(data);
+        
+        *size = 0;
+        return NULL;
+}
+
 /** @}
  */

uspace/lib/c/include/sysinfo.h

@@ -44 +44 @@
 extern int sysinfo_get_value(const char *, sysarg_t *);
 extern void *sysinfo_get_data(const char *, size_t *);
+extern void *sysinfo_get_property(const char *, const char *, size_t *);
 
 #endif