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Overview
Comment: | Identify additional requirements in the sqlite3_vfs object documentation. |
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Downloads: | Tarball | ZIP archive |
Timelines: | family | ancestors | descendants | both | trunk |
Files: | files | file ages | folders |
SHA1: |
47064453c396d5204a851b8ec08d665e |
User & Date: | drh 2010-09-01 19:29:57.000 |
Context
2010-09-02
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04:30 | Fix a few typos. Update evidence marks. (check-in: c90a68b77e user: shaneh tags: trunk) | |
2010-09-01
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19:29 | Identify additional requirements in the sqlite3_vfs object documentation. (check-in: 47064453c3 user: drh tags: trunk) | |
18:00 | Add tests to quota.test. (check-in: ec9af6ebd4 user: dan tags: trunk) | |
Changes
Changes to src/os.c.
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179 180 181 182 183 184 185 186 187 188 189 190 191 192 | return pVfs->xRandomness(pVfs, nByte, zBufOut); } int sqlite3OsSleep(sqlite3_vfs *pVfs, int nMicro){ return pVfs->xSleep(pVfs, nMicro); } int sqlite3OsCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *pTimeOut){ int rc; if( pVfs->iVersion>=2 && pVfs->xCurrentTimeInt64 ){ rc = pVfs->xCurrentTimeInt64(pVfs, pTimeOut); }else{ double r; rc = pVfs->xCurrentTime(pVfs, &r); *pTimeOut = (sqlite3_int64)(r*86400000.0); } | > > > > > > | 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 | return pVfs->xRandomness(pVfs, nByte, zBufOut); } int sqlite3OsSleep(sqlite3_vfs *pVfs, int nMicro){ return pVfs->xSleep(pVfs, nMicro); } int sqlite3OsCurrentTimeInt64(sqlite3_vfs *pVfs, sqlite3_int64 *pTimeOut){ int rc; /* IMPLEMENTATION-OF: R-49045-42493 SQLite will use the xCurrentTimeInt64() ** method to get the current date and time if that method is available ** (if iVersion is 2 or greater and the function pointer is not NULL) and ** will fall back to xCurrentTime() if xCurrentTimeInt64() is ** unavailable. */ if( pVfs->iVersion>=2 && pVfs->xCurrentTimeInt64 ){ rc = pVfs->xCurrentTimeInt64(pVfs, pTimeOut); }else{ double r; rc = pVfs->xCurrentTime(pVfs, &r); *pTimeOut = (sqlite3_int64)(r*86400000.0); } |
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Changes to src/sqlite.h.in.
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748 749 750 751 752 753 754 | ** or modify this field while holding a particular static mutex. ** The application should never modify anything within the sqlite3_vfs ** object once the object has been registered. ** ** The zName field holds the name of the VFS module. The name must ** be unique across all VFS modules. ** | | | | | | > | | | > | | | | | | | 748 749 750 751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794 795 796 797 798 799 800 801 802 803 804 805 806 807 808 809 810 811 812 813 814 815 816 817 818 819 820 821 822 823 824 825 826 827 828 829 830 831 832 833 834 835 836 837 838 839 840 841 842 843 844 845 846 847 848 849 850 851 852 853 854 855 856 857 858 | ** or modify this field while holding a particular static mutex. ** The application should never modify anything within the sqlite3_vfs ** object once the object has been registered. ** ** The zName field holds the name of the VFS module. The name must ** be unique across all VFS modules. ** ** ^SQLite will guarantee that the zFilename parameter to xOpen ** is either a NULL pointer or string obtained ** from xFullPathname(). ^SQLite further guarantees that ** the string will be valid and unchanged until xClose() is ** called. Because of the previous sentence, ** the [sqlite3_file] can safely store a pointer to the ** filename if it needs to remember the filename for some reason. ** If the zFilename parameter to xOpen is a NULL pointer then xOpen ** must invent its own temporary name for the file. ^Whenever the ** xFilename parameter is NULL it will also be the case that the ** flags parameter will include [SQLITE_OPEN_DELETEONCLOSE]. ** ** The flags argument to xOpen() includes all bits set in ** the flags argument to [sqlite3_open_v2()]. Or if [sqlite3_open()] ** or [sqlite3_open16()] is used, then flags includes at least ** [SQLITE_OPEN_READWRITE] | [SQLITE_OPEN_CREATE]. ** If xOpen() opens a file read-only then it sets *pOutFlags to ** include [SQLITE_OPEN_READONLY]. Other bits in *pOutFlags may be set. ** ** ^(SQLite will also add one of the following flags to the xOpen() ** call, depending on the object being opened: ** ** <ul> ** <li> [SQLITE_OPEN_MAIN_DB] ** <li> [SQLITE_OPEN_MAIN_JOURNAL] ** <li> [SQLITE_OPEN_TEMP_DB] ** <li> [SQLITE_OPEN_TEMP_JOURNAL] ** <li> [SQLITE_OPEN_TRANSIENT_DB] ** <li> [SQLITE_OPEN_SUBJOURNAL] ** <li> [SQLITE_OPEN_MASTER_JOURNAL] ** <li> [SQLITE_OPEN_WAL] ** </ul>)^ ** ** The file I/O implementation can use the object type flags to ** change the way it deals with files. For example, an application ** that does not care about crash recovery or rollback might make ** the open of a journal file a no-op. Writes to this journal would ** also be no-ops, and any attempt to read the journal would return ** SQLITE_IOERR. Or the implementation might recognize that a database ** file will be doing page-aligned sector reads and writes in a random ** order and set up its I/O subsystem accordingly. ** ** SQLite might also add one of the following flags to the xOpen method: ** ** <ul> ** <li> [SQLITE_OPEN_DELETEONCLOSE] ** <li> [SQLITE_OPEN_EXCLUSIVE] ** </ul> ** ** The [SQLITE_OPEN_DELETEONCLOSE] flag means the file should be ** deleted when it is closed. ^The [SQLITE_OPEN_DELETEONCLOSE] ** will be set for TEMP databases and their journals, transient ** databases, and subjournals. ** ** ^The [SQLITE_OPEN_EXCLUSIVE] flag is always used in conjunction ** with the [SQLITE_OPEN_CREATE] flag, which are both directly ** analogous to the O_EXCL and O_CREAT flags of the POSIX open() ** API. The SQLITE_OPEN_EXCLUSIVE flag, when paired with the ** SQLITE_OPEN_CREATE, is used to indicate that file should always ** be created, and that it is an error if it already exists. ** It is <i>not</i> used to indicate the file should be opened ** for exclusive access. ** ** ^At least szOsFile bytes of memory are allocated by SQLite ** to hold the [sqlite3_file] structure passed as the third ** argument to xOpen. The xOpen method does not have to ** allocate the structure; it should just fill it in. Note that ** the xOpen method must set the sqlite3_file.pMethods to either ** a valid [sqlite3_io_methods] object or to NULL. xOpen must do ** this even if the open fails. SQLite expects that the sqlite3_file.pMethods ** element will be valid after xOpen returns regardless of the success ** or failure of the xOpen call. ** ** ^The flags argument to xAccess() may be [SQLITE_ACCESS_EXISTS] ** to test for the existence of a file, or [SQLITE_ACCESS_READWRITE] to ** test whether a file is readable and writable, or [SQLITE_ACCESS_READ] ** to test whether a file is at least readable. The file can be a ** directory. ** ** ^SQLite will always allocate at least mxPathname+1 bytes for the ** output buffer xFullPathname. The exact size of the output buffer ** is also passed as a parameter to both methods. If the output buffer ** is not large enough, [SQLITE_CANTOPEN] should be returned. Since this is ** handled as a fatal error by SQLite, vfs implementations should endeavor ** to prevent this by setting mxPathname to a sufficiently large value. ** ** The xRandomness(), xSleep(), xCurrentTime(), and xCurrentTimeInt64() ** interfaces are not strictly a part of the filesystem, but they are ** included in the VFS structure for completeness. ** The xRandomness() function attempts to return nBytes bytes ** of good-quality randomness into zOut. The return value is ** the actual number of bytes of randomness obtained. ** The xSleep() method causes the calling thread to sleep for at ** least the number of microseconds given. ^The xCurrentTime() ** method returns a Julian Day Number for the current date and time as ** a floating point value. ** ^The xCurrentTimeInt64() method returns, as an integer, the Julian ** Day Number multipled by 86400000 (the number of milliseconds in ** a 24-hour day). ** ^SQLite will use the xCurrentTimeInt64() method to get the current ** date and time if that method is available (if iVersion is 2 or ** greater and the function pointer is not NULL) and will fall back ** to xCurrentTime() if xCurrentTimeInt64() is unavailable. */ |
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