| /* |
| ** 2010 October 28 |
| ** |
| ** The author disclaims copyright to this source code. In place of |
| ** a legal notice, here is a blessing: |
| ** |
| ** May you do good and not evil. |
| ** May you find forgiveness for yourself and forgive others. |
| ** May you share freely, never taking more than you give. |
| ** |
| ************************************************************************* |
| ** |
| ** This file contains a VFS "shim" - a layer that sits in between the |
| ** pager and the real VFS - that breaks up a very large database file |
| ** into two or more smaller files on disk. This is useful, for example, |
| ** in order to support large, multi-gigabyte databases on older filesystems |
| ** that limit the maximum file size to 2 GiB. |
| ** |
| ** USAGE: |
| ** |
| ** Compile this source file and link it with your application. Then |
| ** at start-time, invoke the following procedure: |
| ** |
| ** int sqlite3_multiplex_initialize( |
| ** const char *zOrigVfsName, // The underlying real VFS |
| ** int makeDefault // True to make multiplex the default VFS |
| ** ); |
| ** |
| ** The procedure call above will create and register a new VFS shim named |
| ** "multiplex". The multiplex VFS will use the VFS named by zOrigVfsName to |
| ** do the actual disk I/O. (The zOrigVfsName parameter may be NULL, in |
| ** which case the default VFS at the moment sqlite3_multiplex_initialize() |
| ** is called will be used as the underlying real VFS.) |
| ** |
| ** If the makeDefault parameter is TRUE then multiplex becomes the new |
| ** default VFS. Otherwise, you can use the multiplex VFS by specifying |
| ** "multiplex" as the 4th parameter to sqlite3_open_v2() or by employing |
| ** URI filenames and adding "vfs=multiplex" as a parameter to the filename |
| ** URI. |
| ** |
| ** The multiplex VFS allows databases up to 32 GiB in size. But it splits |
| ** the files up into smaller pieces, so that they will work even on |
| ** filesystems that do not support large files. The default chunk size |
| ** is 2147418112 bytes (which is 64KiB less than 2GiB) but this can be |
| ** changed at compile-time by defining the SQLITE_MULTIPLEX_CHUNK_SIZE |
| ** macro. Use the "chunksize=NNNN" query parameter with a URI filename |
| ** in order to select an alternative chunk size for individual connections |
| ** at run-time. |
| */ |
| #include "sqlite3.h" |
| #include <string.h> |
| #include <assert.h> |
| #include <stdlib.h> |
| #include "test_multiplex.h" |
| |
| #ifndef SQLITE_CORE |
| #define SQLITE_CORE 1 /* Disable the API redefinition in sqlite3ext.h */ |
| #endif |
| #include "sqlite3ext.h" |
| |
| /* |
| ** These should be defined to be the same as the values in |
| ** sqliteInt.h. They are defined separately here so that |
| ** the multiplex VFS shim can be built as a loadable |
| ** module. |
| */ |
| #define UNUSED_PARAMETER(x) (void)(x) |
| #define MAX_PAGE_SIZE 0x10000 |
| #define DEFAULT_SECTOR_SIZE 0x1000 |
| |
| /* Maximum chunk number */ |
| #define MX_CHUNK_NUMBER 299 |
| |
| /* First chunk for rollback journal files */ |
| #define SQLITE_MULTIPLEX_JOURNAL_8_3_OFFSET 400 |
| #define SQLITE_MULTIPLEX_WAL_8_3_OFFSET 700 |
| |
| |
| /************************ Shim Definitions ******************************/ |
| |
| #ifndef SQLITE_MULTIPLEX_VFS_NAME |
| # define SQLITE_MULTIPLEX_VFS_NAME "multiplex" |
| #endif |
| |
| /* This is the limit on the chunk size. It may be changed by calling |
| ** the xFileControl() interface. It will be rounded up to a |
| ** multiple of MAX_PAGE_SIZE. We default it here to 2GiB less 64KiB. |
| */ |
| #ifndef SQLITE_MULTIPLEX_CHUNK_SIZE |
| # define SQLITE_MULTIPLEX_CHUNK_SIZE 2147418112 |
| #endif |
| |
| /* This used to be the default limit on number of chunks, but |
| ** it is no longer enforced. There is currently no limit to the |
| ** number of chunks. |
| ** |
| ** May be changed by calling the xFileControl() interface. |
| */ |
| #ifndef SQLITE_MULTIPLEX_MAX_CHUNKS |
| # define SQLITE_MULTIPLEX_MAX_CHUNKS 12 |
| #endif |
| |
| /************************ Object Definitions ******************************/ |
| |
| /* Forward declaration of all object types */ |
| typedef struct multiplexGroup multiplexGroup; |
| typedef struct multiplexConn multiplexConn; |
| |
| /* |
| ** A "multiplex group" is a collection of files that collectively |
| ** makeup a single SQLite DB file. This allows the size of the DB |
| ** to exceed the limits imposed by the file system. |
| ** |
| ** There is an instance of the following object for each defined multiplex |
| ** group. |
| */ |
| struct multiplexGroup { |
| struct multiplexReal { /* For each chunk */ |
| sqlite3_file *p; /* Handle for the chunk */ |
| char *z; /* Name of this chunk */ |
| } *aReal; /* list of all chunks */ |
| int nReal; /* Number of chunks */ |
| char *zName; /* Base filename of this group */ |
| int nName; /* Length of base filename */ |
| int flags; /* Flags used for original opening */ |
| unsigned int szChunk; /* Chunk size used for this group */ |
| unsigned char bEnabled; /* TRUE to use Multiplex VFS for this file */ |
| unsigned char bTruncate; /* TRUE to enable truncation of databases */ |
| }; |
| |
| /* |
| ** An instance of the following object represents each open connection |
| ** to a file that is multiplex'ed. This object is a |
| ** subclass of sqlite3_file. The sqlite3_file object for the underlying |
| ** VFS is appended to this structure. |
| */ |
| struct multiplexConn { |
| sqlite3_file base; /* Base class - must be first */ |
| multiplexGroup *pGroup; /* The underlying group of files */ |
| }; |
| |
| /************************* Global Variables **********************************/ |
| /* |
| ** All global variables used by this file are containing within the following |
| ** gMultiplex structure. |
| */ |
| static struct { |
| /* The pOrigVfs is the real, original underlying VFS implementation. |
| ** Most operations pass-through to the real VFS. This value is read-only |
| ** during operation. It is only modified at start-time and thus does not |
| ** require a mutex. |
| */ |
| sqlite3_vfs *pOrigVfs; |
| |
| /* The sThisVfs is the VFS structure used by this shim. It is initialized |
| ** at start-time and thus does not require a mutex |
| */ |
| sqlite3_vfs sThisVfs; |
| |
| /* The sIoMethods defines the methods used by sqlite3_file objects |
| ** associated with this shim. It is initialized at start-time and does |
| ** not require a mutex. |
| ** |
| ** When the underlying VFS is called to open a file, it might return |
| ** either a version 1 or a version 2 sqlite3_file object. This shim |
| ** has to create a wrapper sqlite3_file of the same version. Hence |
| ** there are two I/O method structures, one for version 1 and the other |
| ** for version 2. |
| */ |
| sqlite3_io_methods sIoMethodsV1; |
| sqlite3_io_methods sIoMethodsV2; |
| |
| /* True when this shim has been initialized. |
| */ |
| int isInitialized; |
| } gMultiplex; |
| |
| /************************* Utility Routines *********************************/ |
| /* |
| ** Compute a string length that is limited to what can be stored in |
| ** lower 30 bits of a 32-bit signed integer. |
| ** |
| ** The value returned will never be negative. Nor will it ever be greater |
| ** than the actual length of the string. For very long strings (greater |
| ** than 1GiB) the value returned might be less than the true string length. |
| */ |
| static int multiplexStrlen30(const char *z){ |
| const char *z2 = z; |
| if( z==0 ) return 0; |
| while( *z2 ){ z2++; } |
| return 0x3fffffff & (int)(z2 - z); |
| } |
| |
| /* |
| ** Generate the file-name for chunk iChunk of the group with base name |
| ** zBase. The file-name is written to buffer zOut before returning. Buffer |
| ** zOut must be allocated by the caller so that it is at least (nBase+5) |
| ** bytes in size, where nBase is the length of zBase, not including the |
| ** nul-terminator. |
| ** |
| ** If iChunk is 0 (or 400 - the number for the first journal file chunk), |
| ** the output is a copy of the input string. Otherwise, if |
| ** SQLITE_ENABLE_8_3_NAMES is not defined or the input buffer does not contain |
| ** a "." character, then the output is a copy of the input string with the |
| ** three-digit zero-padded decimal representation if iChunk appended to it. |
| ** For example: |
| ** |
| ** zBase="test.db", iChunk=4 -> zOut="test.db004" |
| ** |
| ** Or, if SQLITE_ENABLE_8_3_NAMES is defined and the input buffer contains |
| ** a "." character, then everything after the "." is replaced by the |
| ** three-digit representation of iChunk. |
| ** |
| ** zBase="test.db", iChunk=4 -> zOut="test.004" |
| ** |
| ** The output buffer string is terminated by 2 0x00 bytes. This makes it safe |
| ** to pass to sqlite3_uri_parameter() and similar. |
| */ |
| static void multiplexFilename( |
| const char *zBase, /* Filename for chunk 0 */ |
| int nBase, /* Size of zBase in bytes (without \0) */ |
| int flags, /* Flags used to open file */ |
| int iChunk, /* Chunk to generate filename for */ |
| char *zOut /* Buffer to write generated name to */ |
| ){ |
| int n = nBase; |
| memcpy(zOut, zBase, n+1); |
| if( iChunk!=0 && iChunk<=MX_CHUNK_NUMBER ){ |
| #ifdef SQLITE_ENABLE_8_3_NAMES |
| int i; |
| for(i=n-1; i>0 && i>=n-4 && zOut[i]!='.'; i--){} |
| if( i>=n-4 ) n = i+1; |
| if( flags & SQLITE_OPEN_MAIN_JOURNAL ){ |
| /* The extensions on overflow files for main databases are 001, 002, |
| ** 003 and so forth. To avoid name collisions, add 400 to the |
| ** extensions of journal files so that they are 401, 402, 403, .... |
| */ |
| iChunk += SQLITE_MULTIPLEX_JOURNAL_8_3_OFFSET; |
| }else if( flags & SQLITE_OPEN_WAL ){ |
| /* To avoid name collisions, add 700 to the |
| ** extensions of WAL files so that they are 701, 702, 703, .... |
| */ |
| iChunk += SQLITE_MULTIPLEX_WAL_8_3_OFFSET; |
| } |
| #endif |
| sqlite3_snprintf(4,&zOut[n],"%03d",iChunk); |
| n += 3; |
| } |
| |
| assert( zOut[n]=='\0' ); |
| zOut[n+1] = '\0'; |
| } |
| |
| /* Compute the filename for the iChunk-th chunk |
| */ |
| static int multiplexSubFilename(multiplexGroup *pGroup, int iChunk){ |
| if( iChunk>=pGroup->nReal ){ |
| struct multiplexReal *p; |
| p = sqlite3_realloc64(pGroup->aReal, (iChunk+1)*sizeof(*p)); |
| if( p==0 ){ |
| return SQLITE_NOMEM; |
| } |
| memset(&p[pGroup->nReal], 0, sizeof(p[0])*(iChunk+1-pGroup->nReal)); |
| pGroup->aReal = p; |
| pGroup->nReal = iChunk+1; |
| } |
| if( pGroup->zName && pGroup->aReal[iChunk].z==0 ){ |
| char *z; |
| int n = pGroup->nName; |
| z = sqlite3_malloc64( n+5 ); |
| if( z==0 ){ |
| return SQLITE_NOMEM; |
| } |
| multiplexFilename(pGroup->zName, pGroup->nName, pGroup->flags, iChunk, z); |
| pGroup->aReal[iChunk].z = sqlite3_create_filename(z,"","",0,0); |
| sqlite3_free(z); |
| if( pGroup->aReal[iChunk].z==0 ) return SQLITE_NOMEM; |
| } |
| return SQLITE_OK; |
| } |
| |
| /* Translate an sqlite3_file* that is really a multiplexGroup* into |
| ** the sqlite3_file* for the underlying original VFS. |
| ** |
| ** For chunk 0, the pGroup->flags determines whether or not a new file |
| ** is created if it does not already exist. For chunks 1 and higher, the |
| ** file is created only if createFlag is 1. |
| */ |
| static sqlite3_file *multiplexSubOpen( |
| multiplexGroup *pGroup, /* The multiplexor group */ |
| int iChunk, /* Which chunk to open. 0==original file */ |
| int *rc, /* Result code in and out */ |
| int *pOutFlags, /* Output flags */ |
| int createFlag /* True to create if iChunk>0 */ |
| ){ |
| sqlite3_file *pSubOpen = 0; |
| sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs; /* Real VFS */ |
| |
| #ifdef SQLITE_ENABLE_8_3_NAMES |
| /* If JOURNAL_8_3_OFFSET is set to (say) 400, then any overflow files are |
| ** part of a database journal are named db.401, db.402, and so on. A |
| ** database may therefore not grow to larger than 400 chunks. Attempting |
| ** to open chunk 401 indicates the database is full. */ |
| if( iChunk>=SQLITE_MULTIPLEX_JOURNAL_8_3_OFFSET ){ |
| sqlite3_log(SQLITE_FULL, "multiplexed chunk overflow: %s", pGroup->zName); |
| *rc = SQLITE_FULL; |
| return 0; |
| } |
| #endif |
| |
| *rc = multiplexSubFilename(pGroup, iChunk); |
| if( (*rc)==SQLITE_OK && (pSubOpen = pGroup->aReal[iChunk].p)==0 ){ |
| int flags, bExists; |
| flags = pGroup->flags; |
| if( createFlag ){ |
| flags |= SQLITE_OPEN_CREATE; |
| }else if( iChunk==0 ){ |
| /* Fall through */ |
| }else if( pGroup->aReal[iChunk].z==0 ){ |
| return 0; |
| }else{ |
| *rc = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[iChunk].z, |
| SQLITE_ACCESS_EXISTS, &bExists); |
| if( *rc || !bExists ){ |
| if( *rc ){ |
| sqlite3_log(*rc, "multiplexor.xAccess failure on %s", |
| pGroup->aReal[iChunk].z); |
| } |
| return 0; |
| } |
| flags &= ~SQLITE_OPEN_CREATE; |
| } |
| pSubOpen = sqlite3_malloc64( pOrigVfs->szOsFile ); |
| if( pSubOpen==0 ){ |
| *rc = SQLITE_IOERR_NOMEM; |
| return 0; |
| } |
| pGroup->aReal[iChunk].p = pSubOpen; |
| *rc = pOrigVfs->xOpen(pOrigVfs, pGroup->aReal[iChunk].z, pSubOpen, |
| flags, pOutFlags); |
| if( (*rc)!=SQLITE_OK ){ |
| sqlite3_log(*rc, "multiplexor.xOpen failure on %s", |
| pGroup->aReal[iChunk].z); |
| sqlite3_free(pSubOpen); |
| pGroup->aReal[iChunk].p = 0; |
| return 0; |
| } |
| } |
| return pSubOpen; |
| } |
| |
| /* |
| ** Return the size, in bytes, of chunk number iChunk. If that chunk |
| ** does not exist, then return 0. This function does not distingish between |
| ** non-existant files and zero-length files. |
| */ |
| static sqlite3_int64 multiplexSubSize( |
| multiplexGroup *pGroup, /* The multiplexor group */ |
| int iChunk, /* Which chunk to open. 0==original file */ |
| int *rc /* Result code in and out */ |
| ){ |
| sqlite3_file *pSub; |
| sqlite3_int64 sz = 0; |
| |
| if( *rc ) return 0; |
| pSub = multiplexSubOpen(pGroup, iChunk, rc, NULL, 0); |
| if( pSub==0 ) return 0; |
| *rc = pSub->pMethods->xFileSize(pSub, &sz); |
| return sz; |
| } |
| |
| /* |
| ** This is the implementation of the multiplex_control() SQL function. |
| */ |
| static void multiplexControlFunc( |
| sqlite3_context *context, |
| int argc, |
| sqlite3_value **argv |
| ){ |
| int rc = SQLITE_OK; |
| sqlite3 *db = sqlite3_context_db_handle(context); |
| int op = 0; |
| int iVal; |
| |
| if( !db || argc!=2 ){ |
| rc = SQLITE_ERROR; |
| }else{ |
| /* extract params */ |
| op = sqlite3_value_int(argv[0]); |
| iVal = sqlite3_value_int(argv[1]); |
| /* map function op to file_control op */ |
| switch( op ){ |
| case 1: |
| op = MULTIPLEX_CTRL_ENABLE; |
| break; |
| case 2: |
| op = MULTIPLEX_CTRL_SET_CHUNK_SIZE; |
| break; |
| case 3: |
| op = MULTIPLEX_CTRL_SET_MAX_CHUNKS; |
| break; |
| default: |
| rc = SQLITE_NOTFOUND; |
| break; |
| } |
| } |
| if( rc==SQLITE_OK ){ |
| rc = sqlite3_file_control(db, 0, op, &iVal); |
| } |
| sqlite3_result_error_code(context, rc); |
| } |
| |
| /* |
| ** This is the entry point to register the auto-extension for the |
| ** multiplex_control() function. |
| */ |
| static int multiplexFuncInit( |
| sqlite3 *db, |
| char **pzErrMsg, |
| const sqlite3_api_routines *pApi |
| ){ |
| int rc; |
| rc = sqlite3_create_function(db, "multiplex_control", 2, SQLITE_ANY, |
| 0, multiplexControlFunc, 0, 0); |
| return rc; |
| } |
| |
| /* |
| ** Close a single sub-file in the connection group. |
| */ |
| static void multiplexSubClose( |
| multiplexGroup *pGroup, |
| int iChunk, |
| sqlite3_vfs *pOrigVfs |
| ){ |
| sqlite3_file *pSubOpen = pGroup->aReal[iChunk].p; |
| if( pSubOpen ){ |
| pSubOpen->pMethods->xClose(pSubOpen); |
| if( pOrigVfs && pGroup->aReal[iChunk].z ){ |
| pOrigVfs->xDelete(pOrigVfs, pGroup->aReal[iChunk].z, 0); |
| } |
| sqlite3_free(pGroup->aReal[iChunk].p); |
| } |
| sqlite3_free_filename(pGroup->aReal[iChunk].z); |
| memset(&pGroup->aReal[iChunk], 0, sizeof(pGroup->aReal[iChunk])); |
| } |
| |
| /* |
| ** Deallocate memory held by a multiplexGroup |
| */ |
| static void multiplexFreeComponents(multiplexGroup *pGroup){ |
| int i; |
| for(i=0; i<pGroup->nReal; i++){ multiplexSubClose(pGroup, i, 0); } |
| sqlite3_free(pGroup->aReal); |
| pGroup->aReal = 0; |
| pGroup->nReal = 0; |
| } |
| |
| |
| /************************* VFS Method Wrappers *****************************/ |
| |
| /* |
| ** This is the xOpen method used for the "multiplex" VFS. |
| ** |
| ** Most of the work is done by the underlying original VFS. This method |
| ** simply links the new file into the appropriate multiplex group if it is a |
| ** file that needs to be tracked. |
| */ |
| static int multiplexOpen( |
| sqlite3_vfs *pVfs, /* The multiplex VFS */ |
| const char *zName, /* Name of file to be opened */ |
| sqlite3_file *pConn, /* Fill in this file descriptor */ |
| int flags, /* Flags to control the opening */ |
| int *pOutFlags /* Flags showing results of opening */ |
| ){ |
| int rc = SQLITE_OK; /* Result code */ |
| multiplexConn *pMultiplexOpen; /* The new multiplex file descriptor */ |
| multiplexGroup *pGroup = 0; /* Corresponding multiplexGroup object */ |
| sqlite3_file *pSubOpen = 0; /* Real file descriptor */ |
| sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs; /* Real VFS */ |
| int nName = 0; |
| int sz = 0; |
| char *zToFree = 0; |
| |
| UNUSED_PARAMETER(pVfs); |
| memset(pConn, 0, pVfs->szOsFile); |
| assert( zName || (flags & SQLITE_OPEN_DELETEONCLOSE) ); |
| |
| /* We need to create a group structure and manage |
| ** access to this group of files. |
| */ |
| pMultiplexOpen = (multiplexConn*)pConn; |
| |
| if( rc==SQLITE_OK ){ |
| /* allocate space for group */ |
| nName = zName ? multiplexStrlen30(zName) : 0; |
| sz = sizeof(multiplexGroup) /* multiplexGroup */ |
| + nName + 1; /* zName */ |
| pGroup = sqlite3_malloc64( sz ); |
| if( pGroup==0 ){ |
| rc = SQLITE_NOMEM; |
| } |
| } |
| |
| if( rc==SQLITE_OK ){ |
| const char *zUri = (flags & SQLITE_OPEN_URI) ? zName : 0; |
| /* assign pointers to extra space allocated */ |
| memset(pGroup, 0, sz); |
| pMultiplexOpen->pGroup = pGroup; |
| pGroup->bEnabled = (unsigned char)-1; |
| pGroup->bTruncate = (unsigned char)sqlite3_uri_boolean(zUri, "truncate", |
| (flags & SQLITE_OPEN_MAIN_DB)==0); |
| pGroup->szChunk = (int)sqlite3_uri_int64(zUri, "chunksize", |
| SQLITE_MULTIPLEX_CHUNK_SIZE); |
| pGroup->szChunk = (pGroup->szChunk+0xffff)&~0xffff; |
| if( zName ){ |
| char *p = (char *)&pGroup[1]; |
| pGroup->zName = p; |
| memcpy(pGroup->zName, zName, nName+1); |
| pGroup->nName = nName; |
| } |
| if( pGroup->bEnabled ){ |
| /* Make sure that the chunksize is such that the pending byte does not |
| ** falls at the end of a chunk. A region of up to 64K following |
| ** the pending byte is never written, so if the pending byte occurs |
| ** near the end of a chunk, that chunk will be too small. */ |
| #ifndef SQLITE_OMIT_WSD |
| extern int sqlite3PendingByte; |
| #else |
| int sqlite3PendingByte = 0x40000000; |
| #endif |
| while( (sqlite3PendingByte % pGroup->szChunk)>=(pGroup->szChunk-65536) ){ |
| pGroup->szChunk += 65536; |
| } |
| } |
| pGroup->flags = (flags & ~SQLITE_OPEN_URI); |
| rc = multiplexSubFilename(pGroup, 1); |
| if( rc==SQLITE_OK ){ |
| pSubOpen = multiplexSubOpen(pGroup, 0, &rc, pOutFlags, 0); |
| if( pSubOpen==0 && rc==SQLITE_OK ) rc = SQLITE_CANTOPEN; |
| } |
| if( rc==SQLITE_OK ){ |
| sqlite3_int64 sz64; |
| |
| rc = pSubOpen->pMethods->xFileSize(pSubOpen, &sz64); |
| if( rc==SQLITE_OK && zName ){ |
| int bExists; |
| if( flags & SQLITE_OPEN_SUPER_JOURNAL ){ |
| pGroup->bEnabled = 0; |
| }else |
| if( sz64==0 ){ |
| if( flags & SQLITE_OPEN_MAIN_JOURNAL ){ |
| /* If opening a main journal file and the first chunk is zero |
| ** bytes in size, delete any subsequent chunks from the |
| ** file-system. */ |
| int iChunk = 1; |
| do { |
| rc = pOrigVfs->xAccess(pOrigVfs, |
| pGroup->aReal[iChunk].z, SQLITE_ACCESS_EXISTS, &bExists |
| ); |
| if( rc==SQLITE_OK && bExists ){ |
| rc = pOrigVfs->xDelete(pOrigVfs, pGroup->aReal[iChunk].z, 0); |
| if( rc==SQLITE_OK ){ |
| rc = multiplexSubFilename(pGroup, ++iChunk); |
| } |
| } |
| }while( rc==SQLITE_OK && bExists ); |
| } |
| }else{ |
| /* If the first overflow file exists and if the size of the main file |
| ** is different from the chunk size, that means the chunk size is set |
| ** set incorrectly. So fix it. |
| ** |
| ** Or, if the first overflow file does not exist and the main file is |
| ** larger than the chunk size, that means the chunk size is too small. |
| ** But we have no way of determining the intended chunk size, so |
| ** just disable the multiplexor all togethre. |
| */ |
| rc = pOrigVfs->xAccess(pOrigVfs, pGroup->aReal[1].z, |
| SQLITE_ACCESS_EXISTS, &bExists); |
| bExists = multiplexSubSize(pGroup, 1, &rc)>0; |
| if( rc==SQLITE_OK && bExists && sz64==(sz64&0xffff0000) && sz64>0 |
| && sz64!=pGroup->szChunk ){ |
| pGroup->szChunk = (int)sz64; |
| }else if( rc==SQLITE_OK && !bExists && sz64>pGroup->szChunk ){ |
| pGroup->bEnabled = 0; |
| } |
| } |
| } |
| } |
| |
| if( rc==SQLITE_OK ){ |
| if( pSubOpen->pMethods->iVersion==1 ){ |
| pConn->pMethods = &gMultiplex.sIoMethodsV1; |
| }else{ |
| pConn->pMethods = &gMultiplex.sIoMethodsV2; |
| } |
| }else{ |
| multiplexFreeComponents(pGroup); |
| sqlite3_free(pGroup); |
| } |
| } |
| sqlite3_free(zToFree); |
| return rc; |
| } |
| |
| /* |
| ** This is the xDelete method used for the "multiplex" VFS. |
| ** It attempts to delete the filename specified. |
| */ |
| static int multiplexDelete( |
| sqlite3_vfs *pVfs, /* The multiplex VFS */ |
| const char *zName, /* Name of file to delete */ |
| int syncDir |
| ){ |
| int rc; |
| sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs; /* Real VFS */ |
| rc = pOrigVfs->xDelete(pOrigVfs, zName, syncDir); |
| if( rc==SQLITE_OK ){ |
| /* If the main chunk was deleted successfully, also delete any subsequent |
| ** chunks - starting with the last (highest numbered). |
| */ |
| int nName = (int)strlen(zName); |
| char *z; |
| z = sqlite3_malloc64(nName + 5); |
| if( z==0 ){ |
| rc = SQLITE_IOERR_NOMEM; |
| }else{ |
| int iChunk = 0; |
| int bExists; |
| do{ |
| multiplexFilename(zName, nName, SQLITE_OPEN_MAIN_JOURNAL, ++iChunk, z); |
| rc = pOrigVfs->xAccess(pOrigVfs, z, SQLITE_ACCESS_EXISTS, &bExists); |
| }while( rc==SQLITE_OK && bExists ); |
| while( rc==SQLITE_OK && iChunk>1 ){ |
| multiplexFilename(zName, nName, SQLITE_OPEN_MAIN_JOURNAL, --iChunk, z); |
| rc = pOrigVfs->xDelete(pOrigVfs, z, syncDir); |
| } |
| if( rc==SQLITE_OK ){ |
| iChunk = 0; |
| do{ |
| multiplexFilename(zName, nName, SQLITE_OPEN_WAL, ++iChunk, z); |
| rc = pOrigVfs->xAccess(pOrigVfs, z, SQLITE_ACCESS_EXISTS, &bExists); |
| }while( rc==SQLITE_OK && bExists ); |
| while( rc==SQLITE_OK && iChunk>1 ){ |
| multiplexFilename(zName, nName, SQLITE_OPEN_WAL, --iChunk, z); |
| rc = pOrigVfs->xDelete(pOrigVfs, z, syncDir); |
| } |
| } |
| } |
| sqlite3_free(z); |
| } |
| return rc; |
| } |
| |
| static int multiplexAccess(sqlite3_vfs *a, const char *b, int c, int *d){ |
| return gMultiplex.pOrigVfs->xAccess(gMultiplex.pOrigVfs, b, c, d); |
| } |
| static int multiplexFullPathname(sqlite3_vfs *a, const char *b, int c, char *d){ |
| return gMultiplex.pOrigVfs->xFullPathname(gMultiplex.pOrigVfs, b, c, d); |
| } |
| static void *multiplexDlOpen(sqlite3_vfs *a, const char *b){ |
| return gMultiplex.pOrigVfs->xDlOpen(gMultiplex.pOrigVfs, b); |
| } |
| static void multiplexDlError(sqlite3_vfs *a, int b, char *c){ |
| gMultiplex.pOrigVfs->xDlError(gMultiplex.pOrigVfs, b, c); |
| } |
| static void (*multiplexDlSym(sqlite3_vfs *a, void *b, const char *c))(void){ |
| return gMultiplex.pOrigVfs->xDlSym(gMultiplex.pOrigVfs, b, c); |
| } |
| static void multiplexDlClose(sqlite3_vfs *a, void *b){ |
| gMultiplex.pOrigVfs->xDlClose(gMultiplex.pOrigVfs, b); |
| } |
| static int multiplexRandomness(sqlite3_vfs *a, int b, char *c){ |
| return gMultiplex.pOrigVfs->xRandomness(gMultiplex.pOrigVfs, b, c); |
| } |
| static int multiplexSleep(sqlite3_vfs *a, int b){ |
| return gMultiplex.pOrigVfs->xSleep(gMultiplex.pOrigVfs, b); |
| } |
| static int multiplexCurrentTime(sqlite3_vfs *a, double *b){ |
| return gMultiplex.pOrigVfs->xCurrentTime(gMultiplex.pOrigVfs, b); |
| } |
| static int multiplexGetLastError(sqlite3_vfs *a, int b, char *c){ |
| if( gMultiplex.pOrigVfs->xGetLastError ){ |
| return gMultiplex.pOrigVfs->xGetLastError(gMultiplex.pOrigVfs, b, c); |
| }else{ |
| return 0; |
| } |
| } |
| static int multiplexCurrentTimeInt64(sqlite3_vfs *a, sqlite3_int64 *b){ |
| return gMultiplex.pOrigVfs->xCurrentTimeInt64(gMultiplex.pOrigVfs, b); |
| } |
| |
| /************************ I/O Method Wrappers *******************************/ |
| |
| /* xClose requests get passed through to the original VFS. |
| ** We loop over all open chunk handles and close them. |
| ** The group structure for this file is unlinked from |
| ** our list of groups and freed. |
| */ |
| static int multiplexClose(sqlite3_file *pConn){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| multiplexGroup *pGroup = p->pGroup; |
| int rc = SQLITE_OK; |
| multiplexFreeComponents(pGroup); |
| sqlite3_free(pGroup); |
| return rc; |
| } |
| |
| /* Pass xRead requests thru to the original VFS after |
| ** determining the correct chunk to operate on. |
| ** Break up reads across chunk boundaries. |
| */ |
| static int multiplexRead( |
| sqlite3_file *pConn, |
| void *pBuf, |
| int iAmt, |
| sqlite3_int64 iOfst |
| ){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| multiplexGroup *pGroup = p->pGroup; |
| int rc = SQLITE_OK; |
| if( !pGroup->bEnabled ){ |
| sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen==0 ){ |
| rc = SQLITE_IOERR_READ; |
| }else{ |
| rc = pSubOpen->pMethods->xRead(pSubOpen, pBuf, iAmt, iOfst); |
| } |
| }else{ |
| while( iAmt > 0 ){ |
| int i = (int)(iOfst / pGroup->szChunk); |
| sqlite3_file *pSubOpen; |
| pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL, 1); |
| if( pSubOpen ){ |
| int extra = ((int)(iOfst % pGroup->szChunk) + iAmt) - pGroup->szChunk; |
| if( extra<0 ) extra = 0; |
| iAmt -= extra; |
| rc = pSubOpen->pMethods->xRead(pSubOpen, pBuf, iAmt, |
| iOfst % pGroup->szChunk); |
| if( rc!=SQLITE_OK ) break; |
| pBuf = (char *)pBuf + iAmt; |
| iOfst += iAmt; |
| iAmt = extra; |
| }else{ |
| rc = SQLITE_IOERR_READ; |
| break; |
| } |
| } |
| } |
| |
| return rc; |
| } |
| |
| /* Pass xWrite requests thru to the original VFS after |
| ** determining the correct chunk to operate on. |
| ** Break up writes across chunk boundaries. |
| */ |
| static int multiplexWrite( |
| sqlite3_file *pConn, |
| const void *pBuf, |
| int iAmt, |
| sqlite3_int64 iOfst |
| ){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| multiplexGroup *pGroup = p->pGroup; |
| int rc = SQLITE_OK; |
| if( !pGroup->bEnabled ){ |
| sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen==0 ){ |
| rc = SQLITE_IOERR_WRITE; |
| }else{ |
| rc = pSubOpen->pMethods->xWrite(pSubOpen, pBuf, iAmt, iOfst); |
| } |
| }else{ |
| while( rc==SQLITE_OK && iAmt>0 ){ |
| int i = (int)(iOfst / pGroup->szChunk); |
| sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, i, &rc, NULL, 1); |
| if( pSubOpen ){ |
| int extra = ((int)(iOfst % pGroup->szChunk) + iAmt) - |
| pGroup->szChunk; |
| if( extra<0 ) extra = 0; |
| iAmt -= extra; |
| rc = pSubOpen->pMethods->xWrite(pSubOpen, pBuf, iAmt, |
| iOfst % pGroup->szChunk); |
| pBuf = (char *)pBuf + iAmt; |
| iOfst += iAmt; |
| iAmt = extra; |
| } |
| } |
| } |
| return rc; |
| } |
| |
| /* Pass xTruncate requests thru to the original VFS after |
| ** determining the correct chunk to operate on. Delete any |
| ** chunks above the truncate mark. |
| */ |
| static int multiplexTruncate(sqlite3_file *pConn, sqlite3_int64 size){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| multiplexGroup *pGroup = p->pGroup; |
| int rc = SQLITE_OK; |
| if( !pGroup->bEnabled ){ |
| sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen==0 ){ |
| rc = SQLITE_IOERR_TRUNCATE; |
| }else{ |
| rc = pSubOpen->pMethods->xTruncate(pSubOpen, size); |
| } |
| }else{ |
| int i; |
| int iBaseGroup = (int)(size / pGroup->szChunk); |
| sqlite3_file *pSubOpen; |
| sqlite3_vfs *pOrigVfs = gMultiplex.pOrigVfs; /* Real VFS */ |
| /* delete the chunks above the truncate limit */ |
| for(i = pGroup->nReal-1; i>iBaseGroup && rc==SQLITE_OK; i--){ |
| if( pGroup->bTruncate ){ |
| multiplexSubClose(pGroup, i, pOrigVfs); |
| }else{ |
| pSubOpen = multiplexSubOpen(pGroup, i, &rc, 0, 0); |
| if( pSubOpen ){ |
| rc = pSubOpen->pMethods->xTruncate(pSubOpen, 0); |
| } |
| } |
| } |
| if( rc==SQLITE_OK ){ |
| pSubOpen = multiplexSubOpen(pGroup, iBaseGroup, &rc, 0, 0); |
| if( pSubOpen ){ |
| rc = pSubOpen->pMethods->xTruncate(pSubOpen, size % pGroup->szChunk); |
| } |
| } |
| if( rc ) rc = SQLITE_IOERR_TRUNCATE; |
| } |
| return rc; |
| } |
| |
| /* Pass xSync requests through to the original VFS without change |
| */ |
| static int multiplexSync(sqlite3_file *pConn, int flags){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| multiplexGroup *pGroup = p->pGroup; |
| int rc = SQLITE_OK; |
| int i; |
| for(i=0; i<pGroup->nReal; i++){ |
| sqlite3_file *pSubOpen = pGroup->aReal[i].p; |
| if( pSubOpen ){ |
| int rc2 = pSubOpen->pMethods->xSync(pSubOpen, flags); |
| if( rc2!=SQLITE_OK ) rc = rc2; |
| } |
| } |
| return rc; |
| } |
| |
| /* Pass xFileSize requests through to the original VFS. |
| ** Aggregate the size of all the chunks before returning. |
| */ |
| static int multiplexFileSize(sqlite3_file *pConn, sqlite3_int64 *pSize){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| multiplexGroup *pGroup = p->pGroup; |
| int rc = SQLITE_OK; |
| int i; |
| if( !pGroup->bEnabled ){ |
| sqlite3_file *pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen==0 ){ |
| rc = SQLITE_IOERR_FSTAT; |
| }else{ |
| rc = pSubOpen->pMethods->xFileSize(pSubOpen, pSize); |
| } |
| }else{ |
| *pSize = 0; |
| for(i=0; rc==SQLITE_OK; i++){ |
| sqlite3_int64 sz = multiplexSubSize(pGroup, i, &rc); |
| if( sz==0 ) break; |
| *pSize = i*(sqlite3_int64)pGroup->szChunk + sz; |
| } |
| } |
| return rc; |
| } |
| |
| /* Pass xLock requests through to the original VFS unchanged. |
| */ |
| static int multiplexLock(sqlite3_file *pConn, int lock){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| return pSubOpen->pMethods->xLock(pSubOpen, lock); |
| } |
| return SQLITE_BUSY; |
| } |
| |
| /* Pass xUnlock requests through to the original VFS unchanged. |
| */ |
| static int multiplexUnlock(sqlite3_file *pConn, int lock){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| return pSubOpen->pMethods->xUnlock(pSubOpen, lock); |
| } |
| return SQLITE_IOERR_UNLOCK; |
| } |
| |
| /* Pass xCheckReservedLock requests through to the original VFS unchanged. |
| */ |
| static int multiplexCheckReservedLock(sqlite3_file *pConn, int *pResOut){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| return pSubOpen->pMethods->xCheckReservedLock(pSubOpen, pResOut); |
| } |
| return SQLITE_IOERR_CHECKRESERVEDLOCK; |
| } |
| |
| /* Pass xFileControl requests through to the original VFS unchanged, |
| ** except for any MULTIPLEX_CTRL_* requests here. |
| */ |
| static int multiplexFileControl(sqlite3_file *pConn, int op, void *pArg){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| multiplexGroup *pGroup = p->pGroup; |
| int rc = SQLITE_ERROR; |
| sqlite3_file *pSubOpen; |
| |
| if( !gMultiplex.isInitialized ) return SQLITE_MISUSE; |
| switch( op ){ |
| case MULTIPLEX_CTRL_ENABLE: |
| if( pArg ) { |
| int bEnabled = *(int *)pArg; |
| pGroup->bEnabled = (unsigned char)bEnabled; |
| rc = SQLITE_OK; |
| } |
| break; |
| case MULTIPLEX_CTRL_SET_CHUNK_SIZE: |
| if( pArg ) { |
| unsigned int szChunk = *(unsigned*)pArg; |
| if( szChunk<1 ){ |
| rc = SQLITE_MISUSE; |
| }else{ |
| /* Round up to nearest multiple of MAX_PAGE_SIZE. */ |
| szChunk = (szChunk + (MAX_PAGE_SIZE-1)); |
| szChunk &= ~(MAX_PAGE_SIZE-1); |
| pGroup->szChunk = szChunk; |
| rc = SQLITE_OK; |
| } |
| } |
| break; |
| case MULTIPLEX_CTRL_SET_MAX_CHUNKS: |
| rc = SQLITE_OK; |
| break; |
| case SQLITE_FCNTL_SIZE_HINT: |
| case SQLITE_FCNTL_CHUNK_SIZE: |
| /* no-op these */ |
| rc = SQLITE_OK; |
| break; |
| case SQLITE_FCNTL_PRAGMA: { |
| char **aFcntl = (char**)pArg; |
| /* |
| ** EVIDENCE-OF: R-29875-31678 The argument to the SQLITE_FCNTL_PRAGMA |
| ** file control is an array of pointers to strings (char**) in which the |
| ** second element of the array is the name of the pragma and the third |
| ** element is the argument to the pragma or NULL if the pragma has no |
| ** argument. |
| */ |
| if( aFcntl[1] && sqlite3_strnicmp(aFcntl[1],"multiplex_",10)==0 ){ |
| sqlite3_int64 sz = 0; |
| (void)multiplexFileSize(pConn, &sz); |
| /* |
| ** PRAGMA multiplex_truncate=BOOLEAN; |
| ** PRAGMA multiplex_truncate; |
| ** |
| ** Turn the multiplexor truncate feature on or off. Return either |
| ** "on" or "off" to indicate the new setting. If the BOOLEAN argument |
| ** is omitted, just return the current value for the truncate setting. |
| */ |
| if( sqlite3_stricmp(aFcntl[1],"multiplex_truncate")==0 ){ |
| if( aFcntl[2] && aFcntl[2][0] ){ |
| if( sqlite3_stricmp(aFcntl[2], "on")==0 |
| || sqlite3_stricmp(aFcntl[2], "1")==0 ){ |
| pGroup->bTruncate = 1; |
| }else |
| if( sqlite3_stricmp(aFcntl[2], "off")==0 |
| || sqlite3_stricmp(aFcntl[2], "0")==0 ){ |
| pGroup->bTruncate = 0; |
| } |
| } |
| /* EVIDENCE-OF: R-27806-26076 The handler for an SQLITE_FCNTL_PRAGMA |
| ** file control can optionally make the first element of the char** |
| ** argument point to a string obtained from sqlite3_mprintf() or the |
| ** equivalent and that string will become the result of the pragma |
| ** or the error message if the pragma fails. |
| */ |
| aFcntl[0] = sqlite3_mprintf(pGroup->bTruncate ? "on" : "off"); |
| rc = SQLITE_OK; |
| break; |
| } |
| /* |
| ** PRAGMA multiplex_enabled; |
| ** |
| ** Return 0 or 1 depending on whether the multiplexor is enabled or |
| ** disabled, respectively. |
| */ |
| if( sqlite3_stricmp(aFcntl[1],"multiplex_enabled")==0 ){ |
| aFcntl[0] = sqlite3_mprintf("%d", pGroup->bEnabled!=0); |
| rc = SQLITE_OK; |
| break; |
| } |
| /* |
| ** PRAGMA multiplex_chunksize; |
| ** |
| ** Return the chunksize for the multiplexor, or no-op if the |
| ** multiplexor is not active. |
| */ |
| if( sqlite3_stricmp(aFcntl[1],"multiplex_chunksize")==0 |
| && pGroup->bEnabled |
| ){ |
| aFcntl[0] = sqlite3_mprintf("%u", pGroup->szChunk); |
| rc = SQLITE_OK; |
| break; |
| } |
| /* |
| ** PRAGMA multiplex_filecount; |
| ** |
| ** Return the number of disk files currently in use by the |
| ** multiplexor. This should be the total database size size |
| ** divided by the chunksize and rounded up. |
| */ |
| if( sqlite3_stricmp(aFcntl[1],"multiplex_filecount")==0 ){ |
| int n = 0; |
| int ii; |
| for(ii=0; ii<pGroup->nReal; ii++){ |
| if( pGroup->aReal[ii].p!=0 ) n++; |
| } |
| aFcntl[0] = sqlite3_mprintf("%d", n); |
| rc = SQLITE_OK; |
| break; |
| } |
| } |
| /* If the multiplexor does not handle the pragma, pass it through |
| ** into the default case. */ |
| } |
| default: |
| pSubOpen = multiplexSubOpen(pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| rc = pSubOpen->pMethods->xFileControl(pSubOpen, op, pArg); |
| if( op==SQLITE_FCNTL_VFSNAME && rc==SQLITE_OK ){ |
| *(char**)pArg = sqlite3_mprintf("multiplex/%z", *(char**)pArg); |
| } |
| } |
| break; |
| } |
| return rc; |
| } |
| |
| /* Pass xSectorSize requests through to the original VFS unchanged. |
| */ |
| static int multiplexSectorSize(sqlite3_file *pConn){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen && pSubOpen->pMethods->xSectorSize ){ |
| return pSubOpen->pMethods->xSectorSize(pSubOpen); |
| } |
| return DEFAULT_SECTOR_SIZE; |
| } |
| |
| /* Pass xDeviceCharacteristics requests through to the original VFS unchanged. |
| */ |
| static int multiplexDeviceCharacteristics(sqlite3_file *pConn){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| return pSubOpen->pMethods->xDeviceCharacteristics(pSubOpen); |
| } |
| return 0; |
| } |
| |
| /* Pass xShmMap requests through to the original VFS unchanged. |
| */ |
| static int multiplexShmMap( |
| sqlite3_file *pConn, /* Handle open on database file */ |
| int iRegion, /* Region to retrieve */ |
| int szRegion, /* Size of regions */ |
| int bExtend, /* True to extend file if necessary */ |
| void volatile **pp /* OUT: Mapped memory */ |
| ){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| return pSubOpen->pMethods->xShmMap(pSubOpen, iRegion, szRegion, bExtend,pp); |
| } |
| return SQLITE_IOERR; |
| } |
| |
| /* Pass xShmLock requests through to the original VFS unchanged. |
| */ |
| static int multiplexShmLock( |
| sqlite3_file *pConn, /* Database file holding the shared memory */ |
| int ofst, /* First lock to acquire or release */ |
| int n, /* Number of locks to acquire or release */ |
| int flags /* What to do with the lock */ |
| ){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| return pSubOpen->pMethods->xShmLock(pSubOpen, ofst, n, flags); |
| } |
| return SQLITE_BUSY; |
| } |
| |
| /* Pass xShmBarrier requests through to the original VFS unchanged. |
| */ |
| static void multiplexShmBarrier(sqlite3_file *pConn){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| pSubOpen->pMethods->xShmBarrier(pSubOpen); |
| } |
| } |
| |
| /* Pass xShmUnmap requests through to the original VFS unchanged. |
| */ |
| static int multiplexShmUnmap(sqlite3_file *pConn, int deleteFlag){ |
| multiplexConn *p = (multiplexConn*)pConn; |
| int rc; |
| sqlite3_file *pSubOpen = multiplexSubOpen(p->pGroup, 0, &rc, NULL, 0); |
| if( pSubOpen ){ |
| return pSubOpen->pMethods->xShmUnmap(pSubOpen, deleteFlag); |
| } |
| return SQLITE_OK; |
| } |
| |
| /************************** Public Interfaces *****************************/ |
| /* |
| ** CAPI: Initialize the multiplex VFS shim - sqlite3_multiplex_initialize() |
| ** |
| ** Use the VFS named zOrigVfsName as the VFS that does the actual work. |
| ** Use the default if zOrigVfsName==NULL. |
| ** |
| ** The multiplex VFS shim is named "multiplex". It will become the default |
| ** VFS if makeDefault is non-zero. |
| ** |
| ** THIS ROUTINE IS NOT THREADSAFE. Call this routine exactly once |
| ** during start-up. |
| */ |
| int sqlite3_multiplex_initialize(const char *zOrigVfsName, int makeDefault){ |
| sqlite3_vfs *pOrigVfs; |
| if( gMultiplex.isInitialized ) return SQLITE_MISUSE; |
| pOrigVfs = sqlite3_vfs_find(zOrigVfsName); |
| if( pOrigVfs==0 ) return SQLITE_ERROR; |
| assert( pOrigVfs!=&gMultiplex.sThisVfs ); |
| gMultiplex.isInitialized = 1; |
| gMultiplex.pOrigVfs = pOrigVfs; |
| gMultiplex.sThisVfs = *pOrigVfs; |
| gMultiplex.sThisVfs.szOsFile += sizeof(multiplexConn); |
| gMultiplex.sThisVfs.zName = SQLITE_MULTIPLEX_VFS_NAME; |
| gMultiplex.sThisVfs.xOpen = multiplexOpen; |
| gMultiplex.sThisVfs.xDelete = multiplexDelete; |
| gMultiplex.sThisVfs.xAccess = multiplexAccess; |
| gMultiplex.sThisVfs.xFullPathname = multiplexFullPathname; |
| gMultiplex.sThisVfs.xDlOpen = multiplexDlOpen; |
| gMultiplex.sThisVfs.xDlError = multiplexDlError; |
| gMultiplex.sThisVfs.xDlSym = multiplexDlSym; |
| gMultiplex.sThisVfs.xDlClose = multiplexDlClose; |
| gMultiplex.sThisVfs.xRandomness = multiplexRandomness; |
| gMultiplex.sThisVfs.xSleep = multiplexSleep; |
| gMultiplex.sThisVfs.xCurrentTime = multiplexCurrentTime; |
| gMultiplex.sThisVfs.xGetLastError = multiplexGetLastError; |
| gMultiplex.sThisVfs.xCurrentTimeInt64 = multiplexCurrentTimeInt64; |
| |
| gMultiplex.sIoMethodsV1.iVersion = 1; |
| gMultiplex.sIoMethodsV1.xClose = multiplexClose; |
| gMultiplex.sIoMethodsV1.xRead = multiplexRead; |
| gMultiplex.sIoMethodsV1.xWrite = multiplexWrite; |
| gMultiplex.sIoMethodsV1.xTruncate = multiplexTruncate; |
| gMultiplex.sIoMethodsV1.xSync = multiplexSync; |
| gMultiplex.sIoMethodsV1.xFileSize = multiplexFileSize; |
| gMultiplex.sIoMethodsV1.xLock = multiplexLock; |
| gMultiplex.sIoMethodsV1.xUnlock = multiplexUnlock; |
| gMultiplex.sIoMethodsV1.xCheckReservedLock = multiplexCheckReservedLock; |
| gMultiplex.sIoMethodsV1.xFileControl = multiplexFileControl; |
| gMultiplex.sIoMethodsV1.xSectorSize = multiplexSectorSize; |
| gMultiplex.sIoMethodsV1.xDeviceCharacteristics = |
| multiplexDeviceCharacteristics; |
| gMultiplex.sIoMethodsV2 = gMultiplex.sIoMethodsV1; |
| gMultiplex.sIoMethodsV2.iVersion = 2; |
| gMultiplex.sIoMethodsV2.xShmMap = multiplexShmMap; |
| gMultiplex.sIoMethodsV2.xShmLock = multiplexShmLock; |
| gMultiplex.sIoMethodsV2.xShmBarrier = multiplexShmBarrier; |
| gMultiplex.sIoMethodsV2.xShmUnmap = multiplexShmUnmap; |
| sqlite3_vfs_register(&gMultiplex.sThisVfs, makeDefault); |
| |
| sqlite3_auto_extension((void(*)(void))multiplexFuncInit); |
| |
| return SQLITE_OK; |
| } |
| |
| /* |
| ** CAPI: Shutdown the multiplex system - sqlite3_multiplex_shutdown() |
| ** |
| ** All SQLite database connections must be closed before calling this |
| ** routine. |
| ** |
| ** THIS ROUTINE IS NOT THREADSAFE. Call this routine exactly once while |
| ** shutting down in order to free all remaining multiplex groups. |
| */ |
| int sqlite3_multiplex_shutdown(int eForce){ |
| int rc = SQLITE_OK; |
| if( gMultiplex.isInitialized==0 ) return SQLITE_MISUSE; |
| gMultiplex.isInitialized = 0; |
| sqlite3_vfs_unregister(&gMultiplex.sThisVfs); |
| memset(&gMultiplex, 0, sizeof(gMultiplex)); |
| return rc; |
| } |
| |
| /***************************** Test Code ***********************************/ |
| #ifdef SQLITE_TEST |
| #if defined(INCLUDE_SQLITE_TCL_H) |
| # include "sqlite_tcl.h" |
| #else |
| # include "tcl.h" |
| # ifndef SQLITE_TCLAPI |
| # define SQLITE_TCLAPI |
| # endif |
| #endif |
| extern const char *sqlite3ErrName(int); |
| |
| |
| /* |
| ** tclcmd: sqlite3_multiplex_initialize NAME MAKEDEFAULT |
| */ |
| static int SQLITE_TCLAPI test_multiplex_initialize( |
| void * clientData, |
| Tcl_Interp *interp, |
| int objc, |
| Tcl_Obj *CONST objv[] |
| ){ |
| const char *zName; /* Name of new multiplex VFS */ |
| int makeDefault; /* True to make the new VFS the default */ |
| int rc; /* Value returned by multiplex_initialize() */ |
| |
| UNUSED_PARAMETER(clientData); |
| |
| /* Process arguments */ |
| if( objc!=3 ){ |
| Tcl_WrongNumArgs(interp, 1, objv, "NAME MAKEDEFAULT"); |
| return TCL_ERROR; |
| } |
| zName = Tcl_GetString(objv[1]); |
| if( Tcl_GetBooleanFromObj(interp, objv[2], &makeDefault) ) return TCL_ERROR; |
| if( zName[0]=='\0' ) zName = 0; |
| |
| /* Call sqlite3_multiplex_initialize() */ |
| rc = sqlite3_multiplex_initialize(zName, makeDefault); |
| Tcl_SetResult(interp, (char *)sqlite3ErrName(rc), TCL_STATIC); |
| |
| return TCL_OK; |
| } |
| |
| /* |
| ** tclcmd: sqlite3_multiplex_shutdown |
| */ |
| static int SQLITE_TCLAPI test_multiplex_shutdown( |
| void * clientData, |
| Tcl_Interp *interp, |
| int objc, |
| Tcl_Obj *CONST objv[] |
| ){ |
| int rc; /* Value returned by multiplex_shutdown() */ |
| |
| UNUSED_PARAMETER(clientData); |
| |
| if( objc==2 && strcmp(Tcl_GetString(objv[1]),"-force")!=0 ){ |
| objc = 3; |
| } |
| if( (objc!=1 && objc!=2) ){ |
| Tcl_WrongNumArgs(interp, 1, objv, "?-force?"); |
| return TCL_ERROR; |
| } |
| |
| /* Call sqlite3_multiplex_shutdown() */ |
| rc = sqlite3_multiplex_shutdown(objc==2); |
| Tcl_SetResult(interp, (char *)sqlite3ErrName(rc), TCL_STATIC); |
| |
| return TCL_OK; |
| } |
| |
| /* |
| ** Tclcmd: test_multiplex_control HANDLE DBNAME SUB-COMMAND ?INT-VALUE? |
| */ |
| static int SQLITE_TCLAPI test_multiplex_control( |
| ClientData cd, |
| Tcl_Interp *interp, |
| int objc, |
| Tcl_Obj *CONST objv[] |
| ){ |
| int rc; /* Return code from file_control() */ |
| int idx; /* Index in aSub[] */ |
| Tcl_CmdInfo cmdInfo; /* Command info structure for HANDLE */ |
| sqlite3 *db; /* Underlying db handle for HANDLE */ |
| int iValue = 0; |
| void *pArg = 0; |
| |
| struct SubCommand { |
| const char *zName; |
| int op; |
| int argtype; |
| } aSub[] = { |
| { "enable", MULTIPLEX_CTRL_ENABLE, 1 }, |
| { "chunk_size", MULTIPLEX_CTRL_SET_CHUNK_SIZE, 1 }, |
| { "max_chunks", MULTIPLEX_CTRL_SET_MAX_CHUNKS, 1 }, |
| { 0, 0, 0 } |
| }; |
| |
| if( objc!=5 ){ |
| Tcl_WrongNumArgs(interp, 1, objv, "HANDLE DBNAME SUB-COMMAND INT-VALUE"); |
| return TCL_ERROR; |
| } |
| |
| if( 0==Tcl_GetCommandInfo(interp, Tcl_GetString(objv[1]), &cmdInfo) ){ |
| Tcl_AppendResult(interp, "expected database handle, got \"", 0); |
| Tcl_AppendResult(interp, Tcl_GetString(objv[1]), "\"", 0); |
| return TCL_ERROR; |
| }else{ |
| db = *(sqlite3 **)cmdInfo.objClientData; |
| } |
| |
| rc = Tcl_GetIndexFromObjStruct( |
| interp, objv[3], aSub, sizeof(aSub[0]), "sub-command", 0, &idx |
| ); |
| if( rc!=TCL_OK ) return rc; |
| |
| switch( aSub[idx].argtype ){ |
| case 1: |
| if( Tcl_GetIntFromObj(interp, objv[4], &iValue) ){ |
| return TCL_ERROR; |
| } |
| pArg = (void *)&iValue; |
| break; |
| default: |
| Tcl_WrongNumArgs(interp, 4, objv, "SUB-COMMAND"); |
| return TCL_ERROR; |
| } |
| |
| rc = sqlite3_file_control(db, Tcl_GetString(objv[2]), aSub[idx].op, pArg); |
| Tcl_SetResult(interp, (char *)sqlite3ErrName(rc), TCL_STATIC); |
| return (rc==SQLITE_OK) ? TCL_OK : TCL_ERROR; |
| } |
| |
| /* |
| ** This routine registers the custom TCL commands defined in this |
| ** module. This should be the only procedure visible from outside |
| ** of this module. |
| */ |
| int Sqlitemultiplex_Init(Tcl_Interp *interp){ |
| static struct { |
| char *zName; |
| Tcl_ObjCmdProc *xProc; |
| } aCmd[] = { |
| { "sqlite3_multiplex_initialize", test_multiplex_initialize }, |
| { "sqlite3_multiplex_shutdown", test_multiplex_shutdown }, |
| { "sqlite3_multiplex_control", test_multiplex_control }, |
| }; |
| int i; |
| |
| for(i=0; i<sizeof(aCmd)/sizeof(aCmd[0]); i++){ |
| Tcl_CreateObjCommand(interp, aCmd[i].zName, aCmd[i].xProc, 0, 0); |
| } |
| |
| return TCL_OK; |
| } |
| #endif |