diff options
Diffstat (limited to 'apt-pkg/acquire-item.h')
| -rw-r--r-- | apt-pkg/acquire-item.h | 714 |
1 files changed, 685 insertions, 29 deletions
diff --git a/apt-pkg/acquire-item.h b/apt-pkg/acquire-item.h index 90f80368b..323dff256 100644 --- a/apt-pkg/acquire-item.h +++ b/apt-pkg/acquire-item.h @@ -9,8 +9,8 @@ the Owner Acquire class. Derived classes will then call QueueURI to register all the URI's they wish to fetch at the initial moment. - Two item classes are provided to provide functionality for downloading - of Index files and downloading of Packages. + Three item classes are provided to provide functionality for + downloading of Index, Translation and Packages files. A Archive class is provided for downloading .deb files. It does Md5 checking and source location as well as a retry algorithm. @@ -31,67 +31,486 @@ #pragma interface "apt-pkg/acquire-item.h" #endif -// Item to acquire +/** \addtogroup acquire + * @{ + * + * \file acquire-item.h + */ + +/** \brief Represents the process by which a pkgAcquire object should + * retrieve a file or a collection of files. + * + * By convention, Item subclasses should insert themselves into the + * acquire queue when they are created by calling QueueURI(), and + * remove themselves by calling Dequeue() when either Done() or + * Failed() is invoked. Item objects are also responsible for + * notifying the download progress indicator (accessible via + * #Owner->Log) of their status. + * + * \see pkgAcquire + */ class pkgAcquire::Item { protected: - // Some private helper methods for registering URIs + /** \brief The acquire object with which this item is associated. */ pkgAcquire *Owner; + + /** \brief Insert this item into its owner's queue. + * + * \param ItemDesc Metadata about this item (its URI and + * description). + */ inline void QueueURI(ItemDesc &Item) {Owner->Enqueue(Item);}; + + /** \brief Remove this item from its owner's queue. */ inline void Dequeue() {Owner->Dequeue(this);}; - // Safe rename function with timestamp preservation + /** \brief Rename a file without modifying its timestamp. + * + * Many item methods call this as their final action. + * + * \param From The file to be renamed. + * + * \param To The new name of #From. If #To exists it will be + * overwritten. + */ void Rename(string From,string To); public: - // State of the item - enum {StatIdle, StatFetching, StatDone, StatError, StatAuthError} Status; + /** \brief The current status of this item. */ + enum ItemState + { + /** \brief The item is waiting to be downloaded. */ + StatIdle, + + /** \brief The item is currently being downloaded. */ + StatFetching, + + /** \brief The item has been successfully downloaded. */ + StatDone, + + /** \brief An error was encountered while downloading this + * item. + */ + StatError, + + /** \brief The item was downloaded but its authenticity could + * not be verified. + */ + StatAuthError + } Status; + + /** \brief Contains a textual description of the error encountered + * if #Status is #StatError or #StatAuthError. + */ string ErrorText; + + /** \brief The size of the object to fetch. */ unsigned long FileSize; - unsigned long PartialSize; + + /** \brief How much of the object was already fetched. */ + unsigned long PartialSize; + + /** \brief If not \b NULL, contains the name of a subprocess that + * is operating on this object (for instance, "gzip" or "gpgv"). + */ const char *Mode; + + /** \brief A client-supplied unique identifier. + * + * This field is initalized to 0; it is meant to be filled in by + * clients that wish to use it to uniquely identify items. + * + * \todo it's unused in apt itself + */ unsigned long ID; + + /** \brief If \b true, the entire object has been successfully fetched. + * + * Subclasses should set this to \b true when appropriate. + */ bool Complete; + + /** \brief If \b true, the URI of this object is "local". + * + * The only effect of this field is to exclude the object from the + * download progress indicator's overall statistics. + */ bool Local; - // Number of queues we are inserted into + /** \brief The number of fetch queues into which this item has been + * inserted. + * + * There is one queue for each source from which an item could be + * downloaded. + * + * \sa pkgAcquire + */ unsigned int QueueCounter; - // File to write the fetch into + /** \brief The name of the file into which the retrieved object + * will be written. + */ string DestFile; - // Action members invoked by the worker + /** \brief Invoked by the acquire worker when the object couldn't + * be fetched. + * + * This is a branch of the continuation of the fetch process. + * + * \param Message An RFC822-formatted message from the acquire + * method describing what went wrong. Use LookupTag() to parse + * it. + * + * \param Cnf The method via which the worker tried to fetch this object. + * + * \sa pkgAcqMethod + */ virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf); + + /** \brief Invoked by the acquire worker when the object was + * fetched successfully. + * + * Note that the object might \e not have been written to + * DestFile; check for the presence of an Alt-Filename entry in + * Message to find the file to which it was really written. + * + * Done is often used to switch from one stage of the processing + * to the next (e.g. fetching, unpacking, copying). It is one + * branch of the continuation of the fetch process. + * + * \param Message Data from the acquire method. Use LookupTag() + * to parse it. + * \param Size The size of the object that was fetched. + * \param Md5Hash The MD5Sum of the object that was fetched. + * \param Cnf The method via which the object was fetched. + * + * \sa pkgAcqMethod + */ virtual void Done(string Message,unsigned long Size,string Md5Hash, pkgAcquire::MethodConfig *Cnf); + + /** \brief Invoked when the worker starts to fetch this object. + * + * \param Message RFC822-formatted data from the worker process. + * Use LookupTag() to parse it. + * + * \param Size The size of the object being fetched. + * + * \sa pkgAcqMethod + */ virtual void Start(string Message,unsigned long Size); + + /** \brief Custom headers to be sent to the fetch process. + * + * \return a string containing RFC822-style headers that are to be + * inserted into the 600 URI Acquire message sent to the fetch + * subprocess. The headers are inserted after a newline-less + * line, so they should (if nonempty) have a leading newline and + * no trailing newline. + */ virtual string Custom600Headers() {return string();}; + + /** \brief A "descriptive" URI-like string. + * + * \return a URI that should be used to describe what is being fetched. + */ virtual string DescURI() = 0; + /** \brief Short item description. + * + * \return a brief description of the object being fetched. + */ virtual string ShortDesc() {return DescURI();} + + /** \brief Invoked by the worker when the download is completely done. */ virtual void Finished() {}; - // Inquire functions + /** \brief MD5Sum. + * + * \return the MD5Sum of this object, if applicable; otherwise, an + * empty string. + */ virtual string MD5Sum() {return string();}; + + /** \return the acquire process with which this item is associated. */ pkgAcquire *GetOwner() {return Owner;}; + + /** \return \b true if this object is being fetched from a trusted source. */ virtual bool IsTrusted() {return false;}; - + + /** \brief Initialize an item. + * + * Adds the item to the list of items known to the acquire + * process, but does not place it into any fetch queues (you must + * manually invoke QueueURI() to do so). + * + * Initializes all fields of the item other than Owner to 0, + * false, or the empty string. + * + * \param Owner The new owner of this item. + */ Item(pkgAcquire *Owner); + + /** \brief Remove this item from its owner's queue by invoking + * pkgAcquire::Remove. + */ virtual ~Item(); }; -// Item class for index files -class pkgAcqIndex : public pkgAcquire::Item +/** \brief Information about an index patch (aka diff). */ +struct DiffInfo { + /** The filename of the diff. */ + string file; + + /** The sha1 hash of the diff. */ + string sha1; + + /** The size of the diff. */ + unsigned long size; +}; + +/** \brief An item that is responsible for fetching an index file of + * package list diffs and starting the package list's download. + * + * This item downloads the Index file and parses it, then enqueues + * additional downloads of either the individual patches (using + * pkgAcqIndexDiffs) or the entire Packages file (using pkgAcqIndex). + * + * \sa pkgAcqIndexDiffs, pkgAcqIndex + */ +class pkgAcqDiffIndex : public pkgAcquire::Item { + protected: + /** \brief If \b true, debugging information will be written to std::clog. */ + bool Debug; + + /** \brief The item that is currently being downloaded. */ + pkgAcquire::ItemDesc Desc; + + /** \brief The URI of the index file to recreate at our end (either + * by downloading it or by applying partial patches). + */ + string RealURI; + + /** \brief The MD5Sum that the real index file should have after + * all patches have been applied. + */ + string ExpectedMD5; + + /** \brief The index file which will be patched to generate the new + * file. + */ + string CurrentPackagesFile; + + /** \brief A description of the Packages file (stored in + * pkgAcquire::ItemDesc::Description). + */ + string Description; + + public: + // Specialized action members + virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf); + virtual void Done(string Message,unsigned long Size,string Md5Hash, + pkgAcquire::MethodConfig *Cnf); + virtual string DescURI() {return RealURI + "Index";}; + virtual string Custom600Headers(); + + /** \brief Parse the Index file for a set of Packages diffs. + * + * Parses the Index file and creates additional download items as + * necessary. + * + * \param IndexDiffFile The name of the Index file. + * + * \return \b true if the Index file was successfully parsed, \b + * false otherwise. + */ + bool ParseDiffIndex(string IndexDiffFile); + + + /** \brief Create a new pkgAcqDiffIndex. + * + * \param Owner The Acquire object that owns this item. + * + * \param URI The URI of the list file to download. + * + * \param URIDesc A long description of the list file to download. + * + * \param ShortDesc A short description of the list file to download. + * + * \param ExpectedMD5 The list file's MD5 signature. + */ + pkgAcqDiffIndex(pkgAcquire *Owner,string URI,string URIDesc, + string ShortDesc, string ExpectedMD5); +}; + +/** \brief An item that is responsible for fetching all the patches + * that need to be applied to a given package index file. + * + * After downloading and applying a single patch, this item will + * enqueue a new pkgAcqIndexDiffs to download and apply the remaining + * patches. If no patch can be found that applies to an intermediate + * file or if one of the patches cannot be downloaded, falls back to + * downloading the entire package index file using pkgAcqIndex. + * + * \sa pkgAcqDiffIndex, pkgAcqIndex + */ +class pkgAcqIndexDiffs : public pkgAcquire::Item +{ + private: + + /** \brief Queue up the next diff download. + * + * Search for the next available diff that applies to the file + * that currently exists on disk, and enqueue it by calling + * QueueURI(). + * + * \return \b true if an applicable diff was found, \b false + * otherwise. + */ + bool QueueNextDiff(); + + /** \brief Handle tasks that must be performed after the item + * finishes downloading. + * + * Dequeues the item and checks the resulting file's md5sum + * against ExpectedMD5 after the last patch was applied. + * There is no need to check the md5/sha1 after a "normal" + * patch because QueueNextDiff() will check the sha1 later. + * + * \param allDone If \b true, the file was entirely reconstructed, + * and its md5sum is verified. + */ + void Finish(bool allDone=false); + protected: + + /** \brief If \b true, debugging output will be written to + * std::clog. + */ + bool Debug; + + /** \brief A description of the item that is currently being + * downloaded. + */ + pkgAcquire::ItemDesc Desc; + + /** \brief The URI of the package index file that is being + * reconstructed. + */ + string RealURI; + + /** \brief The MD5Sum of the package index file that is being + * reconstructed. + */ + string ExpectedMD5; + + /** A description of the file being downloaded. */ + string Description; + + /** The patches that remain to be downloaded, including the patch + * being downloaded right now. This list should be ordered so + * that each diff appears before any diff that depends on it. + * + * \todo These are indexed by sha1sum; why not use some sort of + * dictionary instead of relying on ordering and stripping them + * off the front? + */ + vector<DiffInfo> available_patches; + /** The current status of this patch. */ + enum DiffState + { + /** \brief The diff is in an unknown state. */ + StateFetchUnkown, + + /** \brief The diff is currently being fetched. */ + StateFetchDiff, + + /** \brief The diff is currently being uncompressed. */ + StateUnzipDiff, + + /** \brief The diff is currently being applied. */ + StateApplyDiff + } State; + + public: + /** \brief Called when the patch file failed to be downloaded. + * + * This method will fall back to downloading the whole index file + * outright; its arguments are ignored. + */ + virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf); + + virtual void Done(string Message,unsigned long Size,string Md5Hash, + pkgAcquire::MethodConfig *Cnf); + virtual string DescURI() {return RealURI + "Index";}; + + /** \brief Create an index diff item. + * + * After filling in its basic fields, this invokes Finish(true) if + * #diffs is empty, or QueueNextDiff() otherwise. + * + * \param Owner The pkgAcquire object that owns this item. + * + * \param URI The URI of the package index file being + * reconstructed. + * + * \param URIDesc A long description of this item. + * + * \param ShortDesc A brief description of this item. + * + * \param ExpectedMD5 The expected md5sum of the completely + * reconstructed package index file; the index file will be tested + * against this value when it is entirely reconstructed. + * + * \param diffs The remaining diffs from the index of diffs. They + * should be ordered so that each diff appears before any diff + * that depends on it. + */ + pkgAcqIndexDiffs(pkgAcquire *Owner,string URI,string URIDesc, + string ShortDesc, string ExpectedMD5, + vector<DiffInfo> diffs=vector<DiffInfo>()); +}; + +/** \brief An acquire item that is responsible for fetching an index + * file (e.g., Packages or Sources). + * + * \sa pkgAcqDiffIndex, pkgAcqIndexDiffs, pkgAcqIndexTrans + * + * \todo Why does pkgAcqIndex have protected members? + */ +class pkgAcqIndex : public pkgAcquire::Item +{ + protected: + + /** \brief If \b true, the index file has been decompressed. */ bool Decompression; + + /** \brief If \b true, the partially downloaded file will be + * removed when the download completes. + */ bool Erase; + + /** \brief The download request that is currently being + * processed. + */ pkgAcquire::ItemDesc Desc; + + /** \brief The object that is actually being fetched (minus any + * compression-related extensions). + */ string RealURI; + + /** \brief The expected md5sum of the decompressed index file. */ string ExpectedMD5; + + /** \brief The compression-related file extension that is being + * added to the downloaded file (e.g., ".gz" or ".bz2"). + */ string CompressionExtension; public: @@ -103,26 +522,120 @@ class pkgAcqIndex : public pkgAcquire::Item virtual string Custom600Headers(); virtual string DescURI() {return RealURI + CompressionExtension;}; + /** \brief Create a pkgAcqIndex. + * + * \param Owner The pkgAcquire object with which this item is + * associated. + * + * \param URI The URI of the index file that is to be downloaded. + * + * \param URIDesc A "URI-style" description of this index file. + * + * \param ShortDesc A brief description of this index file. + * + * \param ExpectedMD5 The expected md5sum of this index file. + * + * \param compressExt The compression-related extension with which + * this index file should be downloaded, or "" to autodetect + * (".bz2" is used if bzip2 is installed, ".gz" otherwise). + */ pkgAcqIndex(pkgAcquire *Owner,string URI,string URIDesc, - string ShortDesct, string ExpectedMD5, string compressExt=""); + string ShortDesc, string ExpectedMD5, string compressExt=""); +}; + +/** \brief An acquire item that is responsible for fetching a + * translated index file. + * + * The only difference from pkgAcqIndex is that transient failures + * are suppressed: no error occurs if the translated index file is + * missing. + */ +class pkgAcqIndexTrans : public pkgAcqIndex +{ + public: + + virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf); + + /** \brief Create a pkgAcqIndexTrans. + * + * \param Owner The pkgAcquire object with which this item is + * associated. + * + * \param URI The URI of the index file that is to be downloaded. + * + * \param URIDesc A "URI-style" description of this index file. + * + * \param ShortDesc A brief description of this index file. + * + * \param ExpectedMD5 The expected md5sum of this index file. + * + * \param compressExt The compression-related extension with which + * this index file should be downloaded, or "" to autodetect + * (".bz2" is used if bzip2 is installed, ".gz" otherwise). + */ + pkgAcqIndexTrans(pkgAcquire *Owner,string URI,string URIDesc, + string ShortDesc); }; +/** \brief Information about an index file. */ struct IndexTarget { + /** \brief A URI from which the index file can be downloaded. */ string URI; + + /** \brief A description of the index file. */ string Description; + + /** \brief A shorter description of the index file. */ string ShortDesc; + + /** \brief The key by which this index file should be + * looked up within the meta signature file. + */ string MetaKey; }; -// Item class for index signatures +/** \brief An acquire item that downloads the detached signature + * of a meta-index (Release) file, then queues up the release + * file itself. + * + * \todo Why protected members? + * + * \sa pkgAcqMetaIndex + */ class pkgAcqMetaSig : public pkgAcquire::Item { protected: - + /** \brief The fetch request that is currently being processed. */ pkgAcquire::ItemDesc Desc; - string RealURI,MetaIndexURI,MetaIndexURIDesc,MetaIndexShortDesc; + + /** \brief The URI of the signature file. Unlike Desc.URI, this is + * never modified; it is used to determine the file that is being + * downloaded. + */ + string RealURI; + + /** \brief The URI of the meta-index file to be fetched after the signature. */ + string MetaIndexURI; + + /** \brief A "URI-style" description of the meta-index file to be + * fetched after the signature. + */ + string MetaIndexURIDesc; + + /** \brief A brief description of the meta-index file to be fetched + * after the signature. + */ + string MetaIndexShortDesc; + + /** \brief A package-system-specific parser for the meta-index file. */ indexRecords* MetaIndexParser; + + /** \brief The index files which should be looked up in the meta-index + * and then downloaded. + * + * \todo Why a list of pointers instead of a list of structs? + */ const vector<struct IndexTarget*>* IndexTargets; public: @@ -134,27 +647,88 @@ class pkgAcqMetaSig : public pkgAcquire::Item virtual string Custom600Headers(); virtual string DescURI() {return RealURI; }; + /** \brief Create a new pkgAcqMetaSig. */ pkgAcqMetaSig(pkgAcquire *Owner,string URI,string URIDesc, string ShortDesc, string MetaIndexURI, string MetaIndexURIDesc, string MetaIndexShortDesc, const vector<struct IndexTarget*>* IndexTargets, indexRecords* MetaIndexParser); }; -// Item class for index signatures +/** \brief An item that is responsible for downloading the meta-index + * file (i.e., Release) itself and verifying its signature. + * + * Once the download and verification are complete, the downloads of + * the individual index files are queued up using pkgAcqDiffIndex. + * If the meta-index file had a valid signature, the expected md5sums + * of the index files will be the md5sums listed in the meta-index; + * otherwise, the expected md5sums will be "" (causing the + * authentication of the index files to be bypassed). + */ class pkgAcqMetaIndex : public pkgAcquire::Item { protected: - + /** \brief The fetch command that is currently being processed. */ pkgAcquire::ItemDesc Desc; - string RealURI; // FIXME: is this redundant w/ Desc.URI? + + /** \brief The URI that is actually being downloaded; never + * modified by pkgAcqMetaIndex. + */ + string RealURI; + + /** \brief The file in which the signature for this index was stored. + * + * If empty, the signature and the md5sums of the individual + * indices will not be checked. + */ string SigFile; + + /** \brief The index files to download. */ const vector<struct IndexTarget*>* IndexTargets; + + /** \brief The parser for the meta-index file. */ indexRecords* MetaIndexParser; + + /** \brief If \b true, the index's signature is currently being verified. + */ bool AuthPass; + /** \brief Check that the release file is a release file for the + * correct distribution. + * + * \return \b true if no fatal errors were encountered. + */ bool VerifyVendor(); + + /** \brief Called when a file is finished being retrieved. + * + * If the file was not downloaded to DestFile, a copy process is + * set up to copy it to DestFile; otherwise, Complete is set to \b + * true and the file is moved to its final location. + * + * \param Message The message block received from the fetch + * subprocess. + */ void RetrievalDone(string Message); + + /** \brief Called when authentication succeeded. + * + * Sanity-checks the authenticated file, queues up the individual + * index files for download, and saves the signature in the lists + * directory next to the authenticated list file. + * + * \param Message The message block received from the fetch + * subprocess. + */ void AuthDone(string Message); + + /** \brief Starts downloading the individual index files. + * + * \param verify If \b true, only indices whose expected md5sum + * can be determined from the meta-index will be downloaded, and + * the md5sums of indices will be checked (reporting + * #StatAuthError if there is a mismatch). If verify is \b false, + * no md5sum checking will be performed. + */ void QueueIndexes(bool verify); public: @@ -166,6 +740,7 @@ class pkgAcqMetaIndex : public pkgAcquire::Item virtual string Custom600Headers(); virtual string DescURI() {return RealURI; }; + /** \brief Create a new pkgAcqMetaIndex. */ pkgAcqMetaIndex(pkgAcquire *Owner, string URI,string URIDesc, string ShortDesc, string SigFile, @@ -173,28 +748,58 @@ class pkgAcqMetaIndex : public pkgAcquire::Item indexRecords* MetaIndexParser); }; -// Item class for archive files +/** \brief An item that is responsible for fetching a package file. + * + * If the package file already exists in the cache, nothing will be + * done. + */ class pkgAcqArchive : public pkgAcquire::Item { protected: - - // State information for the retry mechanism + /** \brief The package version being fetched. */ pkgCache::VerIterator Version; + + /** \brief The fetch command that is currently being processed. */ pkgAcquire::ItemDesc Desc; + + /** \brief The list of sources from which to pick archives to + * download this package from. + */ pkgSourceList *Sources; + + /** \brief A package records object, used to look up the file + * corresponding to each version of the package. + */ pkgRecords *Recs; + + /** \brief The md5sum of this package. */ string MD5; + + /** \brief A location in which the actual filename of the package + * should be stored. + */ string &StoreFilename; + + /** \brief The next file for this version to try to download. */ pkgCache::VerFileIterator Vf; + + /** \brief How many (more) times to try to find a new source from + * which to download this package version if it fails. + * + * Set from Acquire::Retries. + */ unsigned int Retries; + + /** \brief \b true if this version file is being downloaded from a + * trusted source. + */ bool Trusted; - // Queue the next available file for download. + /** \brief Queue up the next available file for this version. */ bool QueueNext(); public: - // Specialized action members virtual void Failed(string Message,pkgAcquire::MethodConfig *Cnf); virtual void Done(string Message,unsigned long Size,string Md5Hash, pkgAcquire::MethodConfig *Cnf); @@ -202,18 +807,49 @@ class pkgAcqArchive : public pkgAcquire::Item virtual string DescURI() {return Desc.URI;}; virtual string ShortDesc() {return Desc.ShortDesc;}; virtual void Finished(); + virtual bool IsTrusted(); + /** \brief Create a new pkgAcqArchive. + * + * \param Owner The pkgAcquire object with which this item is + * associated. + * + * \param Sources The sources from which to download version + * files. + * + * \param Recs A package records object, used to look up the file + * corresponding to each version of the package. + * + * \param Version The package version to download. + * + * \param StoreFilename A location in which the actual filename of + * the package should be stored. It will be set to a guessed + * basename in the constructor, and filled in with a fully + * qualified filename once the download finishes. + */ pkgAcqArchive(pkgAcquire *Owner,pkgSourceList *Sources, pkgRecords *Recs,pkgCache::VerIterator const &Version, string &StoreFilename); }; -// Fetch a generic file to the current directory +/** \brief Retrieve an arbitrary file to the current directory. + * + * The file is retrieved even if it is accessed via a URL type that + * normally is a NOP, such as "file". If the download fails, the + * partial file is renamed to get a ".FAILED" extension. + */ class pkgAcqFile : public pkgAcquire::Item { + /** \brief The currently active download process. */ pkgAcquire::ItemDesc Desc; + + /** \brief The md5sum of the file to download, if it is known. */ string Md5Hash; + + /** \brief How many times to retry the download, set from + * Acquire::Retries. + */ unsigned int Retries; public: @@ -224,9 +860,29 @@ class pkgAcqFile : public pkgAcquire::Item pkgAcquire::MethodConfig *Cnf); virtual string MD5Sum() {return Md5Hash;}; virtual string DescURI() {return Desc.URI;}; - + + /** \brief Create a new pkgAcqFile object. + * + * \param Owner The pkgAcquire object with which this object is + * associated. + * + * \param URI The URI to download. + * + * \param MD5 The md5sum of the file to download, if it is known; + * otherwise "". + * + * \param Size The size of the file to download, if it is known; + * otherwise 0. + * + * \param Desc A description of the file being downloaded. + * + * \param ShortDesc A brief description of the file being + * downloaded. + */ pkgAcqFile(pkgAcquire *Owner,string URI,string MD5,unsigned long Size, string Desc,string ShortDesc); }; +/** @} */ + #endif |