diff options
Diffstat (limited to 'ext/session/changeset.c')
| -rw-r--r-- | ext/session/changeset.c | 417 |
1 files changed, 417 insertions, 0 deletions
diff --git a/ext/session/changeset.c b/ext/session/changeset.c new file mode 100644 index 0000000..9cf6294 --- /dev/null +++ b/ext/session/changeset.c @@ -0,0 +1,417 @@ +/* +** 2014-08-18 +** +** 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 code to implement the "changeset" command line +** utility for displaying and transforming changesets generated by +** the Sessions extension. +*/ +#include "sqlite3.h" +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <assert.h> +#include <ctype.h> + + +/* +** Show a usage message on stderr then quit. +*/ +static void usage(const char *argv0){ + fprintf(stderr, "Usage: %s FILENAME COMMAND ...\n", argv0); + fprintf(stderr, + "COMMANDs:\n" + " apply DB Apply the changeset to database file DB\n" + " concat FILE2 OUT Concatenate FILENAME and FILE2 into OUT\n" + " dump Show the complete content of the changeset\n" + " invert OUT Write an inverted changeset into file OUT\n" + " sql Give a pseudo-SQL rendering of the changeset\n" + ); + exit(1); +} + +/* +** Read the content of a disk file into an in-memory buffer +*/ +static void readFile(const char *zFilename, int *pSz, void **ppBuf){ + FILE *f; + sqlite3_int64 sz; + void *pBuf; + f = fopen(zFilename, "rb"); + if( f==0 ){ + fprintf(stderr, "cannot open \"%s\" for reading\n", zFilename); + exit(1); + } + fseek(f, 0, SEEK_END); + sz = ftell(f); + rewind(f); + pBuf = sqlite3_malloc64( sz ? sz : 1 ); + if( pBuf==0 ){ + fprintf(stderr, "cannot allocate %d to hold content of \"%s\"\n", + (int)sz, zFilename); + exit(1); + } + if( sz>0 ){ + if( fread(pBuf, (size_t)sz, 1, f)!=1 ){ + fprintf(stderr, "cannot read all %d bytes of \"%s\"\n", + (int)sz, zFilename); + exit(1); + } + fclose(f); + } + *pSz = (int)sz; + *ppBuf = pBuf; +} + +/* Array for converting from half-bytes (nybbles) into ASCII hex +** digits. */ +static const char hexdigits[] = { + '0', '1', '2', '3', '4', '5', '6', '7', + '8', '9', 'a', 'b', 'c', 'd', 'e', 'f' +}; + +/* +** Render an sqlite3_value as an SQL string. +*/ +static void renderValue(sqlite3_value *pVal){ + switch( sqlite3_value_type(pVal) ){ + case SQLITE_FLOAT: { + double r1; + char zBuf[50]; + r1 = sqlite3_value_double(pVal); + sqlite3_snprintf(sizeof(zBuf), zBuf, "%!.15g", r1); + printf("%s", zBuf); + break; + } + case SQLITE_INTEGER: { + printf("%lld", sqlite3_value_int64(pVal)); + break; + } + case SQLITE_BLOB: { + char const *zBlob = sqlite3_value_blob(pVal); + int nBlob = sqlite3_value_bytes(pVal); + int i; + printf("x'"); + for(i=0; i<nBlob; i++){ + putchar(hexdigits[(zBlob[i]>>4)&0x0F]); + putchar(hexdigits[(zBlob[i])&0x0F]); + } + putchar('\''); + break; + } + case SQLITE_TEXT: { + const unsigned char *zArg = sqlite3_value_text(pVal); + putchar('\''); + while( zArg[0] ){ + putchar(zArg[0]); + if( zArg[0]=='\'' ) putchar(zArg[0]); + zArg++; + } + putchar('\''); + break; + } + default: { + assert( sqlite3_value_type(pVal)==SQLITE_NULL ); + printf("NULL"); + break; + } + } +} + +/* +** Number of conflicts seen +*/ +static int nConflict = 0; + +/* +** The conflict callback +*/ +static int conflictCallback( + void *pCtx, + int eConflict, + sqlite3_changeset_iter *pIter +){ + int op, bIndirect, nCol, i; + const char *zTab; + unsigned char *abPK; + const char *zType = ""; + const char *zOp = ""; + const char *zSep = " "; + + nConflict++; + sqlite3changeset_op(pIter, &zTab, &nCol, &op, &bIndirect); + sqlite3changeset_pk(pIter, &abPK, 0); + switch( eConflict ){ + case SQLITE_CHANGESET_DATA: zType = "DATA"; break; + case SQLITE_CHANGESET_NOTFOUND: zType = "NOTFOUND"; break; + case SQLITE_CHANGESET_CONFLICT: zType = "PRIMARY KEY"; break; + case SQLITE_CHANGESET_FOREIGN_KEY: zType = "FOREIGN KEY"; break; + case SQLITE_CHANGESET_CONSTRAINT: zType = "CONSTRAINT"; break; + } + switch( op ){ + case SQLITE_UPDATE: zOp = "UPDATE of"; break; + case SQLITE_INSERT: zOp = "INSERT into"; break; + case SQLITE_DELETE: zOp = "DELETE from"; break; + } + printf("%s conflict on %s table %s with primary key", zType, zOp, zTab); + for(i=0; i<nCol; i++){ + sqlite3_value *pVal; + if( abPK[i]==0 ) continue; + printf("%s", zSep); + if( op==SQLITE_INSERT ){ + sqlite3changeset_new(pIter, i, &pVal); + }else{ + sqlite3changeset_old(pIter, i, &pVal); + } + renderValue(pVal); + zSep = ","; + } + printf("\n"); + return SQLITE_CHANGESET_OMIT; +} + +int main(int argc, char **argv){ + int sz, rc; + void *pBuf = 0; + if( argc<3 ) usage(argv[0]); + readFile(argv[1], &sz, &pBuf); + + /* changeset FILENAME apply DB + ** Apply the changeset in FILENAME to the database file DB + */ + if( strcmp(argv[2],"apply")==0 ){ + sqlite3 *db; + if( argc!=4 ) usage(argv[0]); + rc = sqlite3_open(argv[3], &db); + if( rc!=SQLITE_OK ){ + fprintf(stderr, "unable to open database file \"%s\": %s\n", + argv[3], sqlite3_errmsg(db)); + sqlite3_close(db); + exit(1); + } + sqlite3_exec(db, "BEGIN", 0, 0, 0); + nConflict = 0; + rc = sqlite3changeset_apply(db, sz, pBuf, 0, conflictCallback, 0); + if( rc ){ + fprintf(stderr, "sqlite3changeset_apply() returned %d\n", rc); + } + if( nConflict ){ + fprintf(stderr, "%d conflicts - no changes applied\n", nConflict); + sqlite3_exec(db, "ROLLBACK", 0, 0, 0); + }else if( rc ){ + fprintf(stderr, "sqlite3changeset_apply() returns %d " + "- no changes applied\n", rc); + sqlite3_exec(db, "ROLLBACK", 0, 0, 0); + }else{ + sqlite3_exec(db, "COMMIT", 0, 0, 0); + } + sqlite3_close(db); + }else + + /* changeset FILENAME concat FILE2 OUT + ** Add changeset FILE2 onto the end of the changeset in FILENAME + ** and write the result into OUT. + */ + if( strcmp(argv[2],"concat")==0 ){ + int szB; + void *pB; + int szOut; + void *pOutBuf; + FILE *out; + const char *zOut = argv[4]; + if( argc!=5 ) usage(argv[0]); + out = fopen(zOut, "wb"); + if( out==0 ){ + fprintf(stderr, "cannot open \"%s\" for writing\n", zOut); + exit(1); + } + readFile(argv[3], &szB, &pB); + rc = sqlite3changeset_concat(sz, pBuf, szB, pB, &szOut, &pOutBuf); + if( rc!=SQLITE_OK ){ + fprintf(stderr, "sqlite3changeset_concat() returns %d\n", rc); + }else if( szOut>0 && fwrite(pOutBuf, szOut, 1, out)!=1 ){ + fprintf(stderr, "unable to write all %d bytes of output to \"%s\"\n", + szOut, zOut); + } + fclose(out); + sqlite3_free(pOutBuf); + sqlite3_free(pB); + }else + + /* changeset FILENAME dump + ** Show the complete content of the changeset in FILENAME + */ + if( strcmp(argv[2],"dump")==0 ){ + int cnt = 0; + int i; + sqlite3_changeset_iter *pIter; + rc = sqlite3changeset_start(&pIter, sz, pBuf); + if( rc!=SQLITE_OK ){ + fprintf(stderr, "sqlite3changeset_start() returns %d\n", rc); + exit(1); + } + while( sqlite3changeset_next(pIter)==SQLITE_ROW ){ + int op, bIndirect, nCol; + const char *zTab; + unsigned char *abPK; + sqlite3changeset_op(pIter, &zTab, &nCol, &op, &bIndirect); + cnt++; + printf("%d: %s table=[%s] indirect=%d nColumn=%d\n", + cnt, op==SQLITE_INSERT ? "INSERT" : + op==SQLITE_UPDATE ? "UPDATE" : "DELETE", + zTab, bIndirect, nCol); + sqlite3changeset_pk(pIter, &abPK, 0); + for(i=0; i<nCol; i++){ + sqlite3_value *pVal; + pVal = 0; + sqlite3changeset_old(pIter, i, &pVal); + if( pVal ){ + printf(" old[%d]%s = ", i, abPK[i] ? "pk" : " "); + renderValue(pVal); + printf("\n"); + } + pVal = 0; + sqlite3changeset_new(pIter, i, &pVal); + if( pVal ){ + printf(" new[%d]%s = ", i, abPK[i] ? "pk" : " "); + renderValue(pVal); + printf("\n"); + } + } + } + sqlite3changeset_finalize(pIter); + }else + + /* changeset FILENAME invert OUT + ** Invert the changes in FILENAME and writes the result on OUT + */ + if( strcmp(argv[2],"invert")==0 ){ + FILE *out; + int szOut = 0; + void *pOutBuf = 0; + const char *zOut = argv[3]; + if( argc!=4 ) usage(argv[0]); + out = fopen(zOut, "wb"); + if( out==0 ){ + fprintf(stderr, "cannot open \"%s\" for writing\n", zOut); + exit(1); + } + rc = sqlite3changeset_invert(sz, pBuf, &szOut, &pOutBuf); + if( rc!=SQLITE_OK ){ + fprintf(stderr, "sqlite3changeset_invert() returns %d\n", rc); + }else if( szOut>0 && fwrite(pOutBuf, szOut, 1, out)!=1 ){ + fprintf(stderr, "unable to write all %d bytes of output to \"%s\"\n", + szOut, zOut); + } + fclose(out); + sqlite3_free(pOutBuf); + }else + + /* changeset FILE sql + ** Show the content of the changeset as pseudo-SQL + */ + if( strcmp(argv[2],"sql")==0 ){ + int cnt = 0; + char *zPrevTab = 0; + char *zSQLTabName = 0; + sqlite3_changeset_iter *pIter = 0; + rc = sqlite3changeset_start(&pIter, sz, pBuf); + if( rc!=SQLITE_OK ){ + fprintf(stderr, "sqlite3changeset_start() returns %d\n", rc); + exit(1); + } + printf("BEGIN;\n"); + while( sqlite3changeset_next(pIter)==SQLITE_ROW ){ + int op, bIndirect, nCol; + const char *zTab; + sqlite3changeset_op(pIter, &zTab, &nCol, &op, &bIndirect); + cnt++; + if( zPrevTab==0 || strcmp(zPrevTab,zTab)!=0 ){ + sqlite3_free(zPrevTab); + sqlite3_free(zSQLTabName); + zPrevTab = sqlite3_mprintf("%s", zTab); + if( !isalnum(zTab[0]) || sqlite3_strglob("*[^a-zA-Z0-9]*",zTab)==0 ){ + zSQLTabName = sqlite3_mprintf("\"%w\"", zTab); + }else{ + zSQLTabName = sqlite3_mprintf("%s", zTab); + } + printf("/****** Changes for table %s ***************/\n", zSQLTabName); + } + switch( op ){ + case SQLITE_DELETE: { + unsigned char *abPK; + int i; + const char *zSep = " "; + sqlite3changeset_pk(pIter, &abPK, 0); + printf("/* %d */ DELETE FROM %s WHERE", cnt, zSQLTabName); + for(i=0; i<nCol; i++){ + sqlite3_value *pVal; + if( abPK[i]==0 ) continue; + printf("%sc%d=", zSep, i+1); + zSep = " AND "; + sqlite3changeset_old(pIter, i, &pVal); + renderValue(pVal); + } + printf(";\n"); + break; + } + case SQLITE_UPDATE: { + unsigned char *abPK; + int i; + const char *zSep = " "; + sqlite3changeset_pk(pIter, &abPK, 0); + printf("/* %d */ UPDATE %s SET", cnt, zSQLTabName); + for(i=0; i<nCol; i++){ + sqlite3_value *pVal = 0; + sqlite3changeset_new(pIter, i, &pVal); + if( pVal ){ + printf("%sc%d=", zSep, i+1); + zSep = ", "; + renderValue(pVal); + } + } + printf(" WHERE"); + zSep = " "; + for(i=0; i<nCol; i++){ + sqlite3_value *pVal; + if( abPK[i]==0 ) continue; + printf("%sc%d=", zSep, i+1); + zSep = " AND "; + sqlite3changeset_old(pIter, i, &pVal); + renderValue(pVal); + } + printf(";\n"); + break; + } + case SQLITE_INSERT: { + int i; + printf("/* %d */ INSERT INTO %s VALUES", cnt, zSQLTabName); + for(i=0; i<nCol; i++){ + sqlite3_value *pVal; + printf("%c", i==0 ? '(' : ','); + sqlite3changeset_new(pIter, i, &pVal); + renderValue(pVal); + } + printf(");\n"); + break; + } + } + } + printf("COMMIT;\n"); + sqlite3changeset_finalize(pIter); + sqlite3_free(zPrevTab); + sqlite3_free(zSQLTabName); + }else + + /* If nothing else matches, show the usage comment */ + usage(argv[0]); + sqlite3_free(pBuf); + return 0; +} |