/*
- * $Id: StoreSwapLogData.h,v 1.6 2008/02/26 21:49:34 amosjeffries Exp $
+ * $Id$
*
* SQUID Web Proxy Cache http://www.squid-cache.org/
* ----------------------------------------------------------
* the value for MemObject->swap_hdr_sz.
*/
-#include "squid.h"
+#include "md5.h"
+#include "MemPool.h"
+#include "typedefs.h"
+
+/// maintains a 24-bit checksum over integer fields
+class SwapChecksum24
+{
+public:
+ SwapChecksum24() { raw[0] = raw[1] = raw[2] = 0; }
+
+ bool operator ==(const SwapChecksum24 &o) const {
+ return raw[0] == o.raw[0] && raw[1] == o.raw[1] && raw[2] == o.raw[2];
+ }
+
+ bool operator !=(const SwapChecksum24 &o) const {
+ return !(*this == o);
+ }
+
+ /// compute and store checksum based on three 32bit integers
+ void set(uint32_t f1, uint32_t f2, uint32_t f3);
+
+ /// compute and store checksum based on int32_t and uint64_t integers
+ void set(int32_t f1, uint64_t f2);
+
+ // printing for debugging
+ std::ostream &print(std::ostream &os) const;
+
+private:
+ uint8_t raw[3]; // designed to follow "op" members, in pading space
+};
+
+inline std::ostream &
+operator <<(std::ostream &os, const SwapChecksum24 &sum)
+{
+ return sum.print(os);
+}
-/*
- * Do we need to have the dirn in here? I don't think so, since we already
- * know the dirn ..
- */
/**
\ingroup FielFormatSwapStateAPI
- \note This information is current as of version 2.2.STABLE4
- *
- \li Binary format on disk.
- \li DO NOT randomly alter.
- \li DO NOT add ANY virtual's.
*
\par
- * Defines the structure of a binary swap.state file entry.
+ * Defines the structure of a binary swap.state file entry for UFS stores.
+ * TODO: Move to fs/ufs (and remove from COSS).
*
\note StoreSwapLogData entries are written in native machine byte order
* They are not necessarily portable across architectures.
public:
MEMPROXY_CLASS(StoreSwapLogData);
+
+ /// type to use for storing time-related members; must be signed
+ typedef int64_t SwappedTime;
+
StoreSwapLogData();
+ /// consistency self-check: whether the data appears to make sense
+ bool sane() const;
+
+ /// call this before storing the log entry
+ void finalize();
+
/**
* Either SWAP_LOG_ADD when an object is added to the disk storage,
* or SWAP_LOG_DEL when an object is deleted.
*/
- char op;
+ uint8_t op;
+
+ /**
+ * Fingerprint to weed out bogus/corrupted swap.state entries.
+ */
+ SwapChecksum24 checksum; // follows "op" because compiler will pad anyway
/**
* The 32-bit file number which maps to a pathname.
sfileno swap_filen;
/**
- * A 32-bit Unix time value that represents the time when
+ * A Unix time value that represents the time when
* the origin server generated this response. If the response
* has a valid Date: header, this timestamp corresponds
* to that time. Otherwise, it is set to the Squid process time
* when the response is read (as soon as the end of headers are found).
*/
- time_t timestamp;
+ SwappedTime timestamp;
/**
* The last time that a client requested this object.
* Strictly speaking, this time is set whenever the StoreEntry
* is locked (via storeLockObject()).
*/
- time_t lastref;
+ SwappedTime lastref;
/**
* The value of the response's Expires: header, if any.
* where Squid sets expires to -2. This happens for the
* internal "netdb" object and for FTP URL responses.
*/
- time_t expires;
+ SwappedTime expires;
/**
* The value of the response's Last-modified: header, if any.
* This is set to -1 if there is no Last-modified: header,
* or if it is unparseable.
*/
- time_t lastmod;
+ SwappedTime lastmod;
/**
* This is the number of bytes that the object occupies on
* Since its a 16-bit quantity, it is susceptible to overflow
* if a single object is accessed 65,536 times before being replaced.
*/
- u_short refcount;
+ uint16_t refcount;
/**
* A copy of the StoreEntry flags field. Used as a sanity
* check when rebuilding the cache at startup. Objects that
* have the KEY_PRIVATE flag set are not added back to the cache.
*/
- u_short flags;
+ uint16_t flags;
/**
* The 128-bit MD5 hash for this object.
unsigned char key[SQUID_MD5_DIGEST_LENGTH];
};
-MEMPROXY_CLASS_INLINE(StoreSwapLogData) /**DOCS_NOSEMI*/
+MEMPROXY_CLASS_INLINE(StoreSwapLogData);
/// \ingroup FileFormatSwapStateAPI
+/// Swap log starts with this binary structure.
class StoreSwapLogHeader
{
public:
+ // sets default values for this Squid version; loaded values may differ
StoreSwapLogHeader();
- char op;
- int version;
- int record_size;
-};
+ /// consistency self-check: whether the data appears to make sense
+ bool sane() const;
+
+ /// number of bytes after the log header before the first log entry
+ size_t gapSize() const;
+
+ uint8_t op;
+ SwapChecksum24 checksum; // follows "op" because compiler will pad anyway
+ int32_t version;
+ int32_t record_size;
+};
#endif /* SQUID_STORESWAPLOGDATA_H */
projects / thirdparty / squid.git / blobdiff