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	 e3c4751070
			
		
	
	
		e3c4751070
		
	
	
	
	
		
			
			This converts the map validation function into a macro, tweaks the GITERR_OS system error automatic appending, and adds a tentative new error access API and some quick unit tests for both the old and new error APIs.
		
			
				
	
	
		
			116 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			116 lines
		
	
	
		
			2.4 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (C) 2009-2012 the libgit2 contributors
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|  *
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|  * This file is part of libgit2, distributed under the GNU GPL v2 with
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|  * a Linking Exception. For full terms see the included COPYING file.
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|  */
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| 
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| #include "map.h"
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| #include <errno.h>
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| 
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| 
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| static DWORD get_page_size(void)
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| {
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| 	static DWORD page_size;
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| 	SYSTEM_INFO sys;
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| 
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| 	if (!page_size) {
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| 		GetSystemInfo(&sys);
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| 		page_size = sys.dwAllocationGranularity;
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| 	}
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| 
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| 	return page_size;
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| }
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| 
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| int p_mmap(git_map *out, size_t len, int prot, int flags, int fd, git_off_t offset)
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| {
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| 	HANDLE fh = (HANDLE)_get_osfhandle(fd);
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| 	DWORD page_size = get_page_size();
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| 	DWORD fmap_prot = 0;
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| 	DWORD view_prot = 0;
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| 	DWORD off_low = 0;
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| 	DWORD off_hi = 0;
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| 	git_off_t page_start;
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| 	git_off_t page_offset;
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| 
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| 	GIT_MMAP_VALIDATE(out, len, prot, flags);
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| 
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| 	out->data = NULL;
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| 	out->len = 0;
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| 	out->fmh = NULL;
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| 
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| 	if (fh == INVALID_HANDLE_VALUE) {
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| 		errno = EBADF;
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| 		giterr_set(GITERR_OS, "Failed to mmap. Invalid handle value");
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| 		return -1;
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| 	}
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| 
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| 	if (prot & GIT_PROT_WRITE)
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| 		fmap_prot |= PAGE_READWRITE;
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| 	else if (prot & GIT_PROT_READ)
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| 		fmap_prot |= PAGE_READONLY;
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| 
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| 	if (prot & GIT_PROT_WRITE)
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| 		view_prot |= FILE_MAP_WRITE;
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| 	if (prot & GIT_PROT_READ)
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| 		view_prot |= FILE_MAP_READ;
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| 
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| 	page_start = (offset / page_size) * page_size;
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| 	page_offset = offset - page_start;
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| 
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| 	if (page_offset != 0) { /* offset must be multiple of page size */
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| 		errno = EINVAL;
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| 		giterr_set(GITERR_OS, "Failed to mmap. Offset must be multiple of page size");
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| 		return -1;
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| 	}
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| 
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| 	out->fmh = CreateFileMapping(fh, NULL, fmap_prot, 0, 0, NULL);
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| 	if (!out->fmh || out->fmh == INVALID_HANDLE_VALUE) {
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| 		giterr_set(GITERR_OS, "Failed to mmap. Invalid handle value");
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| 		out->fmh = NULL;
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| 		return -1;
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| 	}
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| 
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| 	assert(sizeof(git_off_t) == 8);
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| 
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| 	off_low = (DWORD)(page_start);
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| 	off_hi = (DWORD)(page_start >> 32);
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| 	out->data = MapViewOfFile(out->fmh, view_prot, off_hi, off_low, len);
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| 	if (!out->data) {
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| 		giterr_set(GITERR_OS, "Failed to mmap. No data written");
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| 		CloseHandle(out->fmh);
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| 		out->fmh = NULL;
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| 		return -1;
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| 	}
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| 	out->len = len;
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| 
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| 	return 0;
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| }
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| 
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| int p_munmap(git_map *map)
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| {
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| 	int error = 0;
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| 
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| 	assert(map != NULL);
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| 
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| 	if (map->data) {
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| 		if (!UnmapViewOfFile(map->data)) {
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| 			giterr_set(GITERR_OS, "Failed to munmap. Could not unmap view of file");
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| 			error = -1;
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| 		}
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| 		map->data = NULL;
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| 	}
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| 
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| 	if (map->fmh) {
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| 		if (!CloseHandle(map->fmh)) {
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| 			giterr_set(GITERR_OS, "Failed to munmap. Could not close handle");
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| 			error = -1;
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| 		}
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| 		map->fmh = NULL;
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| 	}
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| 
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| 	return error;
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| }
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| 
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| 
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