diff options
Diffstat (limited to 'src/itzam_util.c')
| -rw-r--r-- | src/itzam_util.c | 308 |
1 files changed, 308 insertions, 0 deletions
diff --git a/src/itzam_util.c b/src/itzam_util.c new file mode 100644 index 0000000..cdfbc66 --- /dev/null +++ b/src/itzam_util.c @@ -0,0 +1,308 @@ +/*
+ Itzam/C (version 6.0) is an embedded database engine written in Standard C.
+
+ Copyright 2011 Scott Robert Ladd. All rights reserved.
+
+ Older versions of Itzam/C are:
+ Copyright 2002, 2004, 2006, 2008 Scott Robert Ladd. All rights reserved.
+
+ Ancestral code, from Java and C++ books by the author, is:
+ Copyright 1992, 1994, 1996, 2001 Scott Robert Ladd. All rights reserved.
+
+ Itzam/C is user-supported open source software. It's continued development is dependent on
+ financial support from the community. You can provide funding by visiting the Itzam/C
+ website at:
+
+ http://www.coyotegulch.com
+
+ You may license Itzam/C in one of two fashions:
+
+ 1) Simplified BSD License (FreeBSD License)
+
+ Redistribution and use in source and binary forms, with or without modification, are
+ permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice, this list of
+ conditions and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice, this list
+ of conditions and the following disclaimer in the documentation and/or other materials
+ provided with the distribution.
+
+ THIS SOFTWARE IS PROVIDED BY SCOTT ROBERT LADD ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+ FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL SCOTT ROBERT LADD OR
+ CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
+ ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+ NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+ The views and conclusions contained in the software and documentation are those of the
+ authors and should not be interpreted as representing official policies, either expressed
+ or implied, of Scott Robert Ladd.
+
+ 2) Closed-Source Proprietary License
+
+ If your project is a closed-source or proprietary project, the Simplified BSD License may
+ not be appropriate or desirable. In such cases, contact the Itzam copyright holder to
+ arrange your purchase of an appropriate license.
+
+ The author can be contacted at:
+
+ scott.ladd@coyotegulch.com
+ scott.ladd@gmail.com
+ http:www.coyotegulch.com
+*/
+
+#include "itzam.h"
+
+#include <stdlib.h>
+#include <errno.h>
+#include <ctype.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+
+#if defined(ITZAM_UNIX)
+#include <sys/mman.h>
+#endif
+
+/*-----------------------------------------------------------------------------
+ * default error handler, for errors outside the scope of valid datafile objects
+ */
+void default_default_error_handler(const char * function_name, itzam_error error)
+{
+ /* default error handler displays a simple message and exits program
+ */
+ fprintf(stderr,"Itzam internal error in %s: %d\n",function_name,error);
+ exit(1);
+}
+
+itzam_error_handler * default_error_handler = default_default_error_handler;
+
+void itzam_set_default_error_handler(itzam_error_handler * handler)
+{
+ if (handler != NULL)
+ default_error_handler = handler;
+}
+
+/*-----------------------------------------------------------------------------
+ * shared memory
+ */
+
+ITZAM_SHMEM_TYPE itzam_shmem_obtain(const char * name, size_t len, itzam_bool * creator)
+{
+#if defined(ITZAM_UNIX)
+ int result;
+
+ result = shm_open(name, O_CREAT | O_EXCL | O_RDWR, S_IRUSR | S_IWUSR);
+
+ if (result < 0)
+ {
+ if (errno == EEXIST)
+ {
+ *creator = itzam_false;
+
+ result = shm_open(name, O_CREAT | O_RDWR, S_IRUSR | S_IWUSR);
+
+ if (result < 0)
+ default_error_handler("itzam_shmem_obtain",ITZAM_ERROR_SHMEM);
+ }
+ }
+ else
+ {
+ *creator = itzam_true;
+
+ if (ftruncate(result, len))
+ default_error_handler("itzam_shmem_obtain",ITZAM_ERROR_SHMEM);
+ }
+
+ return result;
+#else
+ HANDLE result;
+
+ result = OpenFileMapping(FILE_MAP_ALL_ACCESS, FALSE, (LPCSTR)name);
+
+ if ((result == NULL) && (len > 0))
+ {
+ *created = itzam_true;
+ result = CreateFileMapping(INVALID_HANDLE_VALUE, NULL, PAGE_READWRITE, 0, (DWORD)len, (LPCTSTR)name);
+ }
+ else
+ *created = itzam_false;
+
+ if (result == NULL)
+ {
+ if (ERROR_ACCESS_DENIED == GetLastError())
+ default_error_handler("itzam_shmem_obtain",ITZAM_ERROR_SHMEM_PRIVILEGE);
+ else
+ default_error_handler("itzam_shmem_obtain",ITZAM_ERROR_SHMEM);
+ }
+
+ return result;
+#endif
+}
+
+void itzam_shmem_close(ITZAM_SHMEM_TYPE shmem, const char * name)
+{
+#if defined(ITZAM_UNIX)
+ close(shmem);
+ shm_unlink(name);
+#else
+ if (shmem != NULL)
+ CloseHandle(shmem);
+#endif
+}
+
+void * itzam_shmem_getptr(ITZAM_SHMEM_TYPE shmem, size_t len)
+{
+#if defined(ITZAM_UNIX)
+ void * result = mmap(NULL, len, PROT_READ | PROT_WRITE, MAP_SHARED, shmem, 0);
+
+ if (result == MAP_FAILED)
+ default_error_handler("itzam_shmem_obtain",ITZAM_ERROR_SHMEM);
+
+ return result;
+#else
+ void * result = NULL;
+
+ result = (void *)MapViewOfFile(shmem, FILE_MAP_ALL_ACCESS, 0, 0, len);
+
+ if (result == NULL)
+ {
+ if (ERROR_ACCESS_DENIED == GetLastError())
+ default_error_handler("itzam_shmem_obtain",ITZAM_ERROR_SHMEM_PRIVILEGE);
+ else
+ default_error_handler("itzam_shmem_obtain",ITZAM_ERROR_SHMEM);
+ }
+
+ return result;
+#endif
+}
+
+itzam_bool itzam_shmem_freeptr(void * shmem_ptr, size_t len)
+{
+#if defined(ITZAM_UNIX)
+ return (itzam_bool)(0 == munmap(shmem_ptr,len));
+#else
+ return (itzam_bool)UnmapViewOfFile(shmem_ptr);
+#endif
+}
+
+/*-----------------------------------------------------------------------------
+ * file I/O functions
+ */
+
+ITZAM_FILE_TYPE itzam_file_create(const char * filename)
+{
+#if defined(ITZAM_UNIX)
+ return open(filename, O_RDWR | O_CREAT | O_TRUNC, S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH );
+#else
+ HANDLE result = NULL;
+
+ do
+ {
+ result = CreateFile((LPCSTR)filename,
+ GENERIC_READ | GENERIC_WRITE,
+ FILE_SHARE_READ | FILE_SHARE_WRITE,
+ NULL,
+ CREATE_ALWAYS,
+ FILE_FLAG_RANDOM_ACCESS, // | FILE_FLAG_WRITE_THROUGH,
+ NULL);
+
+ if ((result != NULL) && (result != INVALID_HANDLE_VALUE))
+ break;
+
+ if ((result == INVALID_HANDLE_VALUE) && (GetLastError() == ERROR_ACCESS_DENIED))
+ Sleep(250);
+ else
+ break;
+ }
+ while (1);
+
+ return result;
+
+#endif
+}
+
+ITZAM_FILE_TYPE itzam_file_open(const char * filename)
+{
+#if defined(ITZAM_UNIX)
+ return open(filename, O_RDWR);
+#else
+ return CreateFile((LPCSTR)filename,
+ GENERIC_READ | GENERIC_WRITE,
+ FILE_SHARE_READ | FILE_SHARE_WRITE,
+ NULL,
+ OPEN_EXISTING,
+ FILE_FLAG_RANDOM_ACCESS, // | FILE_FLAG_WRITE_THROUGH,
+ NULL);
+
+#endif
+}
+
+itzam_bool itzam_file_close(ITZAM_FILE_TYPE file)
+{
+#if defined(ITZAM_UNIX)
+ return (itzam_bool)(0 == close(file));
+#else
+ return (itzam_bool)CloseHandle(file);
+#endif
+}
+
+itzam_bool itzam_file_read(ITZAM_FILE_TYPE file, void * data, size_t len)
+{
+#if defined(ITZAM_UNIX)
+ return (itzam_bool)(len == read(file,data,len));
+#else
+ DWORD count;
+ return (itzam_bool)ReadFile(file, (LPVOID)data, (DWORD)len, &count, NULL);
+#endif
+}
+
+itzam_bool itzam_file_write(ITZAM_FILE_TYPE file, const void * data, size_t len)
+{
+#if defined(ITZAM_UNIX)
+ return (itzam_bool)(len == write(file,data,len));
+#else
+ DWORD count;
+ return (itzam_bool)WriteFile(file,(LPVOID)data, (DWORD)len, &count, NULL);
+#endif
+}
+
+itzam_ref itzam_file_seek(ITZAM_FILE_TYPE file, itzam_ref pos, int mode)
+{
+#if defined(ITZAM_UNIX)
+ return (itzam_ref)lseek(file,pos,mode);
+#else
+ return (itzam_ref)SetFilePointer(file, (LONG)pos, NULL, mode);
+#endif
+}
+
+itzam_ref itzam_file_tell(ITZAM_FILE_TYPE file)
+{
+#if defined(ITZAM_UNIX)
+ return (itzam_ref)lseek(file,0,SEEK_CUR);
+#else
+ return (itzam_ref)SetFilePointer(file, 0, NULL, FILE_CURRENT);
+#endif
+}
+
+itzam_bool itzam_file_commit(ITZAM_FILE_TYPE file)
+{
+#if defined(ITZAM_UNIX)
+ return true; // (itzam_bool)commit(file);
+#else
+ return (itzam_bool)FlushFileBuffers(file);
+#endif
+}
+
+itzam_bool itzam_file_remove(const char * filename)
+{
+#if defined(ITZAM_UNIX)
+ return (itzam_bool)remove(filename);
+#else
+ return (itzam_bool)DeleteFile((LPCSTR)filename);
+#endif
+}
|