Change memory management strategies to be a pointer to a struct consisting of a start and end function, which also allows the use of custom memory management strategies

1 files changed, 18 insertions, 6 deletions

diff --git a/src/cc4group.h b/src/cc4group.h
index e575a7e..0a3ceb4 100644
--- a/src/cc4group.h
+++ b/src/cc4group.h
@@ -136,6 +136,18 @@ typedef struct {
 typedef void* (*CC4Group_TmpMemoryStrategy)(CC4Group* const this, const size_t size, CC4Group_CleanupJob* cleanupJob);
 
 
+// a memory management strategy
+// actually, a memory management strategy is a pointer to an instance of this struct
+// it consists of a start function (like allocating some memory and making a copy)
+// and of an end function, which does the actual cleanup
+// additionally to the predefined memory management strategies, custom strategies may be used
+typedef struct {
+	void* (*start)(void* const data, const size_t size);
+	void (*end)(void* const data);
+} const CC4Group_MemoryManagement_t;
+typedef CC4Group_MemoryManagement_t* CC4Group_MemoryManagement;
+
+
 // callback types for openWithReadCallback
 
 // the callback has to store a pointer to the newly read data in data, as well as the amount of read data in size
@@ -161,9 +173,9 @@ typedef bool (*CC4Group_WriteCallback)(const void* const data, size_t const size
 // it contains all available methods and constants
 typedef struct {
 	struct {
-		int Take; // cc4group will free the data when its not needed anymore; e.g. in the destructor or when setting the file's data again
-		int Copy; // cc4group will copy the data to use it; the original data is untouched and needs to be freed by the caller whenever desired
-		int Reference; // cc4group will use the data as is (i.e. store the pointer and use it); the caller must guarantee it's validity throughout the groups lifetime (or until the file's data is set to a new pointer) and needs to take care of freeing it afterwards
+		CC4Group_MemoryManagement Take; // cc4group will free the data when its not needed anymore; e.g. in the destructor or when setting the file's data again
+		CC4Group_MemoryManagement Copy; // cc4group will copy the data to use it; the original data is untouched and needs to be freed by the caller whenever desired
+		CC4Group_MemoryManagement Reference; // cc4group will use the data as is (i.e. store the pointer and use it); the caller must guarantee it's validity throughout the groups lifetime (or until the file's data is set to a new pointer) and needs to take care of freeing it afterwards
 	} const MemoryManagement;
 
 
@@ -211,7 +223,7 @@ typedef struct {
 	// see the description of MemoryManagement to know if and when data has to be freed by the caller
 	// if the lazy mode is not used, the data can be freed immediately after this function returns
 	// HINT: the lazy mode is actually not implemented yet, but at least I can't forget to mention it here anymore when it's actually done
-	bool (*openMemory)(CC4Group* const this, const void* const groupData, size_t const size, int const memoryManagement);
+	bool (*openMemory)(CC4Group* const this, const void* const groupData, size_t const size, CC4Group_MemoryManagement const memoryManagement);
 
 	// opens a group through a file descriptor
 	// the file descriptor must have been opened with read access and must be in blocking mode (should be default if O_NONBLOCK is not specified)
@@ -226,7 +238,7 @@ typedef struct {
 	// initCallback is called before readCallback is called and deinitCallback is called after all read operations are done
 	// initCallback and deinitCallback may be NULL if they should not be used
 	// even when using the Reference memory management, the buffer returned by the readCallback may be reused across callback calls
-	bool (*openWithReadCallback)(CC4Group* const this, CC4Group_ReadCallback const readCallback, void* const callbackArg, int const memoryManagement, CC4Group_ReadSetupCallback const initCallback, CC4Group_ReadSetupCallback const deinitCallback);
+	bool (*openWithReadCallback)(CC4Group* const this, CC4Group_ReadCallback const readCallback, void* const callbackArg, CC4Group_MemoryManagement const memoryManagement, CC4Group_ReadSetupCallback const initCallback, CC4Group_ReadSetupCallback const deinitCallback);
 
 
 	// saves the current in-memory state of the group as a compressed c4group to disk
@@ -287,7 +299,7 @@ typedef struct {
 
 	// overwrites the data of the file denoted by entryPath with data indicated by data and size
 	// see the description of MemoryManagement to know if and when data has to be freed by the caller
-	bool (*setEntryData)(CC4Group* const this, const char* const entryPath, const void* const data, size_t const size, int const memoryManagementMode);
+	bool (*setEntryData)(CC4Group* const this, const char* const entryPath, const void* const data, size_t const size, CC4Group_MemoryManagement const memoryManagementMode);
 
 
 	// group metadata handling