Fossil

  int nPrepare;             /* Number of calls to sqlite3_prepare() */
  int nDeleteOnFail;        /* Number of entries in azDeleteOnFail[] */
  struct sCommitHook {
    int (*xHook)(void);         /* Functions to call at db_end_transaction() */
    int sequence;               /* Call functions in sequence order */
  } aHook[5];
  char *azDeleteOnFail[3];  /* Files to delete on a failure */
  char *azBeforeCommit[5];  /* Commands to run prior to COMMIT */
  int nBeforeCommit;        /* Number of entries in azBeforeCommit */
} db = {0, 0, 0, 0, 0, 0, };

/*
** Arrange for the given file to be deleted on a failure.
*/
void db_delete_on_failure(const char *zFilename){
  assert( db.nDeleteOnFail<count(db.azDeleteOnFail) );

void db_end_transaction(int rollbackFlag){
  if( g.db==0 ) return;
  if( db.nBegin<=0 ) return;
  if( rollbackFlag ) db.doRollback = 1;
  db.nBegin--;
  if( db.nBegin==0 ){
    int i;
    if( db.doRollback==0 ){
      while( db.nBeforeCommit ){
        db.nBeforeCommit--;
        db_multi_exec(db.azBeforeCommit[db.nBeforeCommit]);
        sqlite3_free(db.azBeforeCommit[db.nBeforeCommit]);
      }
      leaf_do_pending_checks();
    }
    for(i=0; db.doRollback==0 && i<db.nCommitHook; i++){
      db.doRollback |= db.aHook[i].xHook();
    }
    while( db.pAllStmt ){
      db_finalize(db.pAllStmt);
    }
    db_multi_exec(db.doRollback ? "ROLLBACK" : "COMMIT");

  rc = sqlite3_exec(g.db, blob_buffer(&sql), 0, 0, &zErr);
  if( rc!=SQLITE_OK ){
    db_err("%s\n%s", zErr, blob_buffer(&sql));
  }
  blob_reset(&sql);
  return rc;
}

/*
** Optionally make the following changes to the database if feasible and
** convenient.  Do not start a transaction for these changes, but only
** make these changes if other changes are also being made.
*/
void db_optional_sql(const char *zSql, ...){
  if( db.nBeforeCommit < count(db.azBeforeCommit) ){
    va_list ap;
    va_start(ap, zSql);
    db.azBeforeCommit[db.nBeforeCommit++] = sqlite3_vmprintf(zSql, ap);
    va_end(ap);
  }
}

/*
** Execute a query and return a single integer value.
*/
i64 db_int64(i64 iDflt, const char *zSql, ...){
  va_list ap;
  Stmt s;

    Blob localRoot;
    file_canonical_name(g.zLocalRoot, &localRoot, 1);
    db_multi_exec(
      "REPLACE INTO global_config(name, value)"
      "VALUES('ckout:%q','%q');",
      blob_str(&localRoot), blob_str(&full)
    );
    db_optional_sql("REPLACE INTO config(name,value,mtime)"
                    "VALUES('ckout:%q',1,now())",
                    blob_str(&localRoot));
    blob_reset(&localRoot);
  }
  db_swap_connections();
  blob_reset(&full);
}

/*

  if( zComment ){
    fossil_print("comment:      ");
    comment_print(zComment, 14, 79);
    free(zComment);
  }
}

/*
** Print information about the URLs used to access a repository and
** checkouts in a repository.
*/
static void extraRepoInfo(void){
  Stmt s;
  db_prepare(&s, "SELECT substr(name,7), date(mtime,'unixepoch')"
                 "  FROM config"
                 " WHERE name GLOB 'ckout:*' ORDER BY name");
  while( db_step(&s)==SQLITE_ROW ){
    const char *zName;
    const char *zCkout = db_column_text(&s, 0);
    if( g.localOpen ){
      if( fossil_strcmp(zCkout, g.zLocalRoot)==0 ) continue;
      zName = "alt-root:";
    }else{
      zName = "check-out:";
    }
    fossil_print("%-11s   %-54s %s\n", zName, zCkout,
                 db_column_text(&s, 1));
  }
  db_finalize(&s);
  db_prepare(&s, "SELECT substr(name,9), date(mtime,'unixepoch')"
                 "  FROM config"
                 " WHERE name GLOB 'baseurl:*' ORDER BY name");
  while( db_step(&s)==SQLITE_ROW ){
    fossil_print("access-url:   %-54s %s\n", db_column_text(&s, 0),
                 db_column_text(&s, 1));
  }
  db_finalize(&s);
}


/*
** COMMAND: info
**
** Usage: %fossil info ?VERSION | REPOSITORY_FILENAME? ?OPTIONS?
**
** With no arguments, provide information about the current tree.

  i64 fsize;
  if( g.argc==3 && (fsize = file_size(g.argv[2]))>0 && (fsize&0x1ff)==0 ){
    db_open_config(0);
    db_record_repository_filename(g.argv[2]);
    db_open_repository(g.argv[2]);
    fossil_print("project-name: %s\n", db_get("project-name", "<unnamed>"));
    fossil_print("project-code: %s\n", db_get("project-code", "<none>"));
    extraRepoInfo();
    return;
  }
  db_find_and_open_repository(0,0);
  if( g.argc==2 ){
    int vid;
         /* 012345678901234 */
    db_record_repository_filename(0);
    fossil_print("project-name: %s\n", db_get("project-name", "<unnamed>"));
    if( g.localOpen ){
      fossil_print("repository:   %s\n", db_repository_filename());
      fossil_print("local-root:   %s\n", g.zLocalRoot);
    }
    extraRepoInfo();
#if defined(_WIN32)
    if( g.zHome ){
      fossil_print("user-home:    %s\n", g.zHome);
    }
#endif
    fossil_print("project-code: %s\n", db_get("project-code", ""));
    vid = g.localOpen ? db_lget_int("checkout", 0) : 0;

  if( fossil_stricmp(zMode,"on")==0 ){
    g.zBaseURL = mprintf("https://%s%.*s", zHost, i, zCur);
    g.zTop = &g.zBaseURL[8+strlen(zHost)];
  }else{
    g.zBaseURL = mprintf("http://%s%.*s", zHost, i, zCur);
    g.zTop = &g.zBaseURL[7+strlen(zHost)];
  }
  db_optional_sql("REPLACE INTO config(name,value,mtime)"
                  "VALUES('baseurl:%q',1,now())", g.zBaseURL);
}

/*
** Send an HTTP redirect back to the designated Index Page.
*/
NORETURN void fossil_redirect_home(void){
  cgi_redirectf("%s%s", g.zTop, db_get("index-page", "/index"));